ENDODONTOID LAND SNAILS FROM PACIFIC
ISLANDS
(Mollusca: Pulmonata: Sigmurethra)
:
Family Endodontidae
./. . ". ' i
Museum of Natural History
Chicago, Illinois
LIBRARY OF THE
UNIVERSITY OF ILLINOIS
AT URBANA-CHAMPAIGN
AUG 1 6 1977
ENDODONTOID LAND SNAILS FROM PACIFIC
ISLANDS
(Mollusca: Pulmonata: Sigmurethra)
Part I
Family Endodontidae
Alan Solem
Curator of Invertebrates
Field Museum of Natural History
With the technical assistance of
Barbara K. Solem
Field Museum of Natural History
Chicago, Illinois
Published by
Field Museum of Natural History
October 29, 1976
This monograph was prepared with the support of National Science
Foundation grant No. DEB75-14048. Any opinions, findings, conclusions, or
recommendations expressed in such a publication are those of the author and
do not necessarily reflect the views of NSF.
Library of Congress Catalog Card Number: 76-9516
US ISSN 0015-0754
INTKI) IN THE UNITED STATES OF AMERICA
II
v. L
CONTENTS
LIST OF FIGURES VI
LIST OF TABLES X
INTRODUCTION „ 1
Acknowledgements 5
PREVIOUS STUDIES 7
MATERIAL STUDIED 9
METHODS OF ANALYSIS n
Variation in adult shells 11
Nature of quantitative data presented 12
Sample bias 13
Measurement reliability 14
Criteria for species recognition 15
Nature of comparative remarks 17
PATTERNS OF MORPHOLOGICAL VARIATION 19
Size and shape variations 19
Body whorl contour 21
Spire protrusion 24
Umbilical contour 26
Brood-chamber formation 27
Effects of whorl increment 30
Shell sculpture 30
Types and growth patterns 30
Family-level differences 36
Other sculptural elements 37
Patterns of variation 39
Correlated variations 44
Rib spacing 44
Rib reduction 47
Functional significance of sculpture 50
Other external shell features 50
Apertural barriers 52
Parietal barriers 54
Columellar barriers 57
Palatal barriers 59
Parietal and palatal barrier traces and expansion correlations 63
Barrier growth 63
Microdenticulations 65
Barrier numbers and length 65
Degree of apertural narrowing 71
Summary of barrier variation 72
Gross anatomy 72
Genital system 73
Ovotestis 73
Hermaphroditic duct 75
Talon and carrefour 76
Albumen gland 77
Prostate and uterus 77
Terminal male genitalia 78
Terminal female genitalia 83
III
IV
Pallial complex 84
87
Digestive system c
Free muscle system "4
Nervous system 94
External body features 94
Patterns of elongation "4
Summary of anatomical variation 98
HABITAT RANGE AND EXTINCTION 100
PHYLOGENY AND CLASSIFICATION 102
Phylogenetic position of the endodontoid snails 102
Family classification of the endodontoids 105
Phylogeny within the Endodontidae 107
Portrait of a generalized endodontid 109
Identifiable major trends 109
Phylogenetic conclusions HO
Fossil endodontoid land snails 116
Previous generic classifications 118
Proposed generic classification 119
SYSTEMATIC REVIEW 121
List of the taxa 122
Geographic keys to the genera 124
Genus Minidonta, new genus 126
Key to the genus 130
Group of Minidonta micra 130
Group of Minidonta micraconica 135
Group of Minidonta rotellina 139
Group of Minidonta anatonuana 139
Group of Minidonta simulata 146
Genus Mautodontha, new genus 151
Key to the genus 154
Subgenus Mautodontha, s. s 154
Subgenus Garrettoconcha, new subgenus 162
Genus Anceyodonta, new genus 178
Key to the genus 186
Genus Cookeconcha, new genus 207
Genus Kleokyphus, new genus 224
Genus Opanara, new genus 227
Key to the genus 232
Genus Rhysoconcha, new genus 255
Genus Ruatara, new genus 265
Genus Orangia, new genus ....276
Key to the genus ....278
Genus Australdonta, new genus ,...289
Key to the genus ....294
Genus Taipidon, new genus ....314
Key to the genus ....317
Group of Taipidon analogica ....318
Group of Taipidon centadentata ....330
Group of Taipidon varidentata ....333
Genus Planudonta, new genus 335
Key to the genus 337
Genus Rikitea, new genus 342
Genus Nesodiscus Thiele, 1931 345
Key to the genus 35^
Genus Nesophila Pilsbry, 1893 365
Genus Kondoconcha, new genus 36g
Genus Endodonta Albers, 1850 371
Genus Pseudolibera, new genus 383
Genus Libera Garrett, 1881 385
Key to the genus 390
Genus Gambiodonta, new genus 431
Key to the genus 434
Genus Thaumatodon Pilsbry, 1893 444
Key to the genus 448
Group of Thaumatodon decemplicata 448
Group of Thaumatodon hystricelloides 453
Group of Thaumatodon subdaedalea 461
Genus Priceconcha Solem, 1973 465
Genus Zyzzyxdonta, new genus 466
Genus Adadonta, new genus 467
Key to the genus 473
ZOOGEOGRAPHY 488
SUMMARY 493
REFERENCES 494
APPENDIX: Anatomical terms 501
INDICES..., 502
LIST OF FIGURES
1. Frequency distribution of whorl counts in adult Libera fratercula 12
2. Frequency distribution of shell height in adult Libera fratercula 12
3. Frequency distribution of Height /Diameter ratio in adult Libera fratercula 13
4. Frequency distribution of shell diameter in adult Libera fratercula 13
5. Method of measuring specimens 14
6. Frequency distributions of shell height in the Endodontidae 20
7. Frequency distributions of shell diameter in the Endodontidae 20
8. Frequency distributions of Height /Diameter ratios in the Endodontidae 20
9. Frequency distributions of whorl counts in the Endodontidae 20
10. Frequency distributions of D/U ratios in the Endodontidae 21
11. Pattern of umbilical size in Rapa and Mangareva Island Endodontidae 22
12. Frequency distributions of rib counts in the Endodontidae 22
13. Pattern of rib spacing on the body whorl 22
14. Effects of changes in peripheral whorl contour 23
15. Effects of changes in spire protrusion 25
16. Patterns of phyletic change in umbilical contours 27
17. Mean shell height in species with and without a brood chamber 28
18. Mean shell diameter in species with and without a brood chamber 29
19. Mean Height/Diameter ratio in species with and without a brood chamber 29
20. Mean whorl count in species with and without a brood chamber 29
21. Sculpture of Rhysoconcha atanuiensis and Thaumatodon decemplicata (Mousson) 31
22. Sculpture in Gambiodonta 32
23. Postnuclear sculpture of Australdonta raivavaeana 33
24. Patterns of radial surface sculpture in selected Endodontidae 34
25. Sculpture of Minidonta hendersoni 35
26. Postapical sculpture of Cookeconcha decussatulus (Pease) 36
27. Sculpture of Mautodontha (M.) aoraiensis 37
28. Sculpture of Aaadonta constricta constricta (Semper) 38
29. Sculptural details on Aaadonta constricta constricta 39
30. Apical microsculpture in Cookeconcha 40
31. Apical and postnuclear sculpture of Libera bursatella bursatella (Gould) and Nesodiscus taneae
(Garrett) 41
32. Method of sculptural measurements in the Endodontidae 42
33. Correlation between rib count and shell diameter in Opanara areaensis areaensis from Station 383...4S
34. Correlation of ribs and ribs/mm, in Opanara areaensis 43
35. Relationship of mean shell diameter to major rib spacing in Minidonta, Anceyodonta, and
Gambiodonta 48
36. Apertural barrier terminology and numbering system 52
37. Apertural barrier form in the Endodontidae 52
38. Variation in parietal barriers 53
39. Shell sculpture and denticle structure in Opanara areaensis 55
40. Palatal barrier resorption surface in Thaumatodon spirrhymatum 64
41. Palatal barrier sculpture in Thaumatodon hystricelloides (Mousson) 64
42. Palatal barrier sculpture in Hawaiian Endodontidae 66
43. Method of measuring parietal and palatal barrier lengths 70
44. Ovotestis structure and position in the Endodontidae and Pacific Island Charopidae 74
45. Hermaphroditic duct variation in Endodontidae 75
46. Vas deferens entrance and penial retractor muscle insertion patterns 78
47. Pilaster cross-sectional patterns in typical Endodontidae 80
48. Spermathecal insertion patterns 84
VI
VII
49. Anatomy of Taipidon petricola decora 85
50. Pallial cavity length variations 86
51. Radular teeth of Libera fratercula rarotongensis 88
52. Radular teeth of Taipidon petricola decora 89
53. Radular teeth of Endodonta fricki (Pfeiffer) 90
54. Radular teeth of Thaumatodon hystricelloides (Mousson) 91
55. Animal length and shell whorl count in elongated taxa 95
56. Penis length and shell diameter in the Endodontidae 96
57. Phyletic diagram of the Endodontidae 110
58. Levels of specialization in the Endodontidae, size range within genera, and hypothesized directions of
evolutionary change Ill
59. Computer generated phylogeny of Thaumatodon, Zyzzyxdonta, and Aaadonta 114
60. Computer generated phylogeny of Taipidon and generalized Rapan genera 115
61. Computer generated phylogeny of Minidonta, Mautodontha, Kleokyphus, and Cookeconcha
subpacificus 117
62. Minidonta manuaensis, M. inexpectans, and M. rotellina 131
63. Minidonta micra and M. hendersoni 133
64. Anatomy of Minidonta, Mautodontha, Rhysoconcha, and Ruatara 136
65. Minidonta micraconica and M. gravacosta 138
66. Correlation of height and diameter in Minidonta anatonuana, M. haplaenopla, and M. planulata 140
67. Correlation of diameter and D/U ratio in Minidonta anatonuana, M. haplaenopla, and M.
planulata 141
68. Minidonta anatonuana and M. sulcata 142
69. Minidonta planulata and M. haplaenopla 144
70. Minidonta simulata and M. taunensis 147
71. Minidonta taravensis and M. extraria 149
72. Mautodontha (M.) boraborensis and M. (M.) ceuthma 152
73. Mautodontha (M.) zebrina and M. (M.) daedalea 157
74. Mautodontha (M.) zimmermani and M. (M.) aoraiensis 160
75. Mautodontha (Garrettoconcha) saintjohni and M. (G.) consobrina 167
76. Mautodontha (Garrettoconcha) maupiensis, M. (G.) punctiperforata, and M. (G.) imperforata 169
77. Mautodontha (Garrettoconcha) parvidens, M. (G.) subtilis, and M. (G.) rarotongensis 172
78. Mautodontha (Garrettoconcha) consimilis, M. (G.) acuticosta, and M. (G.) unilamellata 175
79. Relationship of height to diameter in Mautodontha consimilis and M. acuticosta 176
80. Relationship of whorls to diameter in Mautodontha consimilis and M. acuticosta 177
81. Anceyodonta ganhutuensis and A. subconica 187
82. Anceyodonta constricta, A. alternata, and A. andersoni 190
83. Anceyodonta difficilis and A. soror 193
84. Relationship of height to diameter in Anceyodonta soror and A. difficilis 194
85. Relationship of H/D ratio to D/U ratio in Anceyodonta soror and A. difficilis 195
86. Anceyodonta sexlamellata 197
87. Anceyodonta densicostata and A. labiosa 200
88. Anceyodonta obesa 201
89. Anceyodonta obesa 202
90. Anceyodonta hamyana 205
91. Relationship between mean diameter and mean ribs/mm, in Cookeconcha 211
92. Cookeconcha subpacificus 212
93. Cookeconcha stelluhis 218
94. Cookeconcha thaanumi and C. luctiferus 219
95. Kleokyphus callimus and K. hypsus 225
96. Anatomy of Opanara depasoapicata, O. bitridentata, O. duplicidentata, and O. a. areaensis 228
97. Anatomy of Opanara altiapica, O. m. megomphala, O. m. tepiahuensis, O. fosbergi, and O.
perahuensis 229
98. Relationship of height to diameter in Opanara bitridentata, O. caliculata, O. depasoapicata, and O.
duplicidentata 230
99. Distribution of Opanara in the Mt. Perahu region 231
100. Distribution of Opanara megomphala, O. caliculata, and O. altiapica 232
101. Distribution of Opanara areaensis 232
102. Opanara bitridentata and O. duplicidentata 234
VIII
103. Carrefour region in Opanara duplicidentata 238
104. Opanara areaensis and subspecies 243
105. Opanara caliculata and O. altiapica 247
106. Opanara m. megomphala and O. m. tepiahuensis 250
107. Opanara per ahuensis, O. fosbergi, and O. depasoapicata 252
108. Structure of parietal barriers in Rhysoconcha variumbilicata and Kondoconcha othnius 255
109. Distribution of Rhysoconcha 258
110. Ribs and rib spacing in Rhysoconcha species and hybrids 259
111. Size and shape frequencies in Rhysoconcha species and hybrids 260
112. Rhysoconcha variumbilicata and R. atanuiensis 263
113. Ruatara koarana and R. o. oparica 266
114. Ruatara oparica normalis and R. o. reductidenta 268
115. Barrier number variation in Ruatara oparica 270
116. Distribution of Ruatara oparica 273
117. Distribution of Orangia 277
118. Umbilical closure in Orangia c. cookei 277
119. Proportions of closed and barely perforate umbilici in Orangia 278
120. Ribs and ribs/mm, in Orangia 279
121. Anatomy of Orangia 280
122. Correlation of height and diameter in Orangia cookei 281
123. Shells of Orangia species and subspecies 282
124. Microsculpture of Australdonta raivavaeana 290
125. Anatomy of Australdonta 293
126. Apertural barrier numbers in Australdonta species 294
127. Australdonta magnasulcata and A. pseudplanulata 295
128. Australdonta degagei and A. rimatarana 297
129. Australdonta tapina and A. yoshii 301
130. H/D and D/U ratio correlation in Australdonta degagei, A. rimatarana, and A. tapina 302
131. Relationship of height and diameter in Australdonta degagei, A. rimatarana, and A. tapina 303
132. Australdonta r. radiella and A. r. rurutuensis 305
133. Australdonta raivavaeana and A. tubuaiana 308
134. Frequency distributions of apertural barriers in populations of Australdonta raivavaeana 309
135. Correlation of parietal and columellar barrier numbers in Australdonta raivavaeana 310
136. Relationship of height and diameter in Australdonta raivavaeana and A. tubuaiana 312
137. Australdonta pharcata and A. ectopia 313
138. Anatomy of Taipidon petricola, T. fragila, and T. varidentata 320
139. Anatomy of Taipidon semimarsupialis and T. centadentata 321
140. Taipidon p. petricola and T. p. decora 322
141. Taipidon woapoensis and T. octolamellata 325
142. Taipidon anceyana and T. marquesana 327
143. Taipidon analogica and T. semimarsupialis 329
144. Taipidon centadentata 332
145. Taipidon fragila and T. varidentata 334
146. Origin of umbilical sculptural pattern in Planudonta 336
147. Anatomy of Planudonta 338
148. Planudonta subplanula 340
149. Planudonta concava, P. intermedia, and P. matauuna 341
150. Rikitea insolens ...344
151. Umbilical mucus cover in Nesodiscus taneae 345
152. Shape variation in Nesodiscus taneae 348
153. Early whorl measurement standard for Nesodiscus 349
154. Anatomy of Nesodiscus f ictus 350
155. Nesodiscus huaheinensis and N. taneae 353
156. Nesodiscus obolus form obolus and N. o. form acetabulum 355
157. Relationship of height and diameter in Nesodiscus obolus ...356
158. Nesodiscus obolus form celsus ...357
159. Nesodiscus cretaceus and N. fabrefactus \ar.piceus ...359
160. Nesodiscus fabrefactus and N. f ictus ...361
161. Nesodiscus magnificus ...365
IX
162. Kondoconcha othnius 369
163. Anatomy of Endodonta fricki 372
164. Anatomy of Endodonta fricki 373
165. Anatomy of Endodonta lamellosa, Nesophila tiara, Cookeconcha jugosus, and C. hystricellus 374
166. Endodonta ekahanuiensis 375
167. Hawaiian Endodonta 379
168. Pseudolibera lillianae 384
169. Apical sculpture of Libera b. bursatella 387
170. Body whorl deflection and umbilical closure in Libera recedens 389
171. Anatomy of Libera b. bursatella and L. micrasoma 396
172. Anatomy of Libera cookeana and L. fratercula rarotongensis 399
173. Libera cookeana and L. micrasoma 401
174. Libera bursatella bursatella and L. b. orofenensis 403
175. Libera gregaria and L. recedens 404
176. Libera dubiosa 406
177. Libera spuria and L. garrettiana 408
178. Libera umbilicata and L. retunsa 411
179. Libera streptaxon and L. jacquinoti 414
180. Umbilical exit from brood chamber in Libera streptaxon 415
181. Libera incognata and L. heynemanni 416
182. Libera f. fratercula and L. f. rarotongensis 422
183. Ribs and ribs/mm, correlation in Libera fratercula 424
184. Libera (L.) subcavernula and L. (L.) tumuloides 427
185. Umbilical closure in Gambiodonta pilsbryi aukenensis 432
186. Gambiodonta agakauitaiana and G. mangarevana 435
187. Gambiodonta p. pilsbryi and G. p. aukenensis 437
188. Gambiodonta tumida and G. mirabilis 439
189. Gambiodonta grandis 442
190. Distribution of Thaumatodon and Zyzzyxdonta 447
191. Anatomy of Thaumatodon hystricelloides and T. decemplicata 449
192. Thaumatodon multilamellata 450
193. Thaumatodon decemplicata and T. laddi 452
194. Thaumatodon euaensis and T. hystricelloides 457
195. Anatomy of Thaumatodon euaensis 459
196. Thaumatodon vavauensis and T. corrugata 460
197. Thaumatodon subdaedalea and T. hystricelloides 462
198. Zyzzyxdonta alata 466
199. Anatomy of Aaadonta (c.) constricta and A. (f. ) fuscozonata 471
200. Anatomy of Aaadonta kinlochi 472
201. Size and shape variation in Aaadonta kinlochi, A. constricta, and A. irregularis 473
202. Proportionate differences between A. angaurana and A. c. constricta 473
203. Aaadonta c. constricta and A. irregularis 475
204. Aaadonta constricta komakanensis, A. c. babelthuapi, and A. angaurana 477
205. Proportionate differences between Aaadonta pelewana and A. fuscozonata 479
206. Aaadonta f. fuscozonata and A. f. depressa 480
207. Aaadonta pelewana 482
208. Aaadonta kinlochi and apertures of A. c. constricta and Thaumatodon hystricelloides 486
LIST OF TABLES
I. Pacific Island endodontoid taxa 2
II. Hawaiian endodontoids 3
III. Dates of species descriptions 3
IV. Summary of material studied 9
V. Frequency distribution of specimens examined per species level taxon 10
VI. Size and shape variation in relict, allopatric Rapan Opanara 17
VII. Whorl contour and whorl count correlations 24
VIII. Spire protrusion and whorl count correlation 24
IX. Size and shape correlations with umbilical contour changes 26
X. Umbilical contour and spire protrusion 28
XI. Whorl count correlated size increment 30
XII. Rib counts in Opanara areaensis from Station 383 42
XIII. Pattern of rib spacing in Opanara areaensis from Station 383 43
XIV. Correlation of microradial counts with major rib counts and shell diameter in the
Endodontidae 44
XV. Shell diameter and rib spacing in the Endodontidae 44
XVI. Correlation between rib spacing and shell diameter in the Endodontidae 45
XVII. Size and degree of sculpture reduction in larger Endodontidae 46
XVIII. Shell size and sculpture reduction in Polynesian Endodontidae 47
XIX. Shell size and subperipheral rib reduction in larger Endodontidae 49
XX. Body whorl descension and shell size 50
XXI. Body whorl contour and rate of descent 51
XXII. Correlation between sulci and body whorl contour 51
XXIII. Presence of trace barriers in the Endodontidae 54
XXIV. Correlation between number of parietal barriers and descension of 2nd parietal barrier 56
XXV. Correlation between anterior descension of 2nd parietal barrier, diameter, and whorl count in
species with 2 parietal barriers 56
XXVI. Correlation between diameter and superior structure of parietal barriers 56
XXVII. Loss of columellar barrier 58
XXVIII. Correlation between columellar barrier height and positional relation to lip edge 58
XXIX. Columellar barrier position and recession 59
XXX. Shell size and columellar barrier position 59
XXXI. Shell size and columellar barrier height 59
XXXII. Palatal barrier shape and length correlations 60
XXXIII. Palatal barrier recession and size correlations 60
XXXIV. Phyletic correlations of palatal barrier recession 61
XXXV. Size correlation with palatal barrier expansion 61
XXXVI. Patterns of barrier expansion 62
XXXVII. Reduction and loss of palatal barriers 62
XXXVIII. Correlation of unusual palatal barrier expansion with parietal barrier expansion 63
XXXIX. Percentage distribution of parietal barrier numbers 65
XL. Percentage distribution of palatal barrier numbers 67
XLI. Phyletic correlation of parietal barrier numbers 68
XLII. Size correlation of parietal barrier numbers 69
XLIII. Phyletic correlations of palatal barrier numbers 69
XLIV. Size correlation of palatal barrier numbers 69
XLV. Correlation of parietal and palatal barrier numbers 70
XLVI. Parietal barrier length and size correlations 70
XLVII. Palatal barrier length and size correlations 70
XLVIII. Degree of apertural narrowing by barriers ...71
X
XI
XLIX. Correlation of apertural narrowing and body whorl contour 72
L. Phyletic representation of dissected taxa 73
LI. Correlation of penial pilaster shape and relative size 81
LH. Sympatric variability in penis size and pilaster patterns in Rapan taxa 82
LIII. Sympatric variability in penis size and pilaster patterns in Tahitian species 82
LIV. Sympatric variability in penis size and pilaster patterns in Marquesan species 82
LV. Radular tooth size and numbers in Nesophila, Cookeconcha, Taipidon, and Planudonta 93
LVI. Shell size and jaw structure in the Endodontidae 94
LVII. Patterns of aulacopod radular dentition 97
LVIII. Major differences between Endodontidae and Charopidae 97
LIX. Minor differences between Endodontidae and Charopidae 98
LX. Shell parameters of the Endodontidae 109
LXI. Shell parameters for levels of organization 113
LXII. Frequency distribution of species/genus in Pacific Island endodontoids 120
LXIII. Range of variation in Minidonta 129
LXIV. Local variation in Minidonta 145
LXV. Range of variation in.Mautodontha (Mautodontha) 155
LXVI. Range of variation in Mautodontha (Garrettoconcha) 163
LXVII. Local variation in Mautodontha 164
LXVIII. Character states typifying A nceyodon ta 180
LXIX. Range of variation in Anceyodonta 181
LXX. Local variation in Anceyodonta 182
LXXI. Geographic distribution and relative abundance of Mangarevan Endodontidae 185
LXXII. Percentage species composition of Mangarevan Anceyodonta in selected samples 186
LXXIII. Barrier variation in Anceyodonta hamyana 207
LXXIV. Local variation in Cookeconcha 208
LXXV. Range of variation in Opanara and Kleokyphus 223
LXXVI. Local variation in Opanara, Ruatara koarana, and Kondoconcha othnius 236
LXXVII. Ribs/mm, in Opanara 237
LXXVIII. Parietal barrier variation in Opanara bitridentata 237
LXXIX. Local variation in Opanara areaensis 240
LXXX. Rib variation in Opanara areaensis 241
LXXXI. Range of variation in Rhysoconcha, Ruatara, Kondoconcha, and Orangia .257
LXXXII. Differences between Rhysoconcha variumbilicata and R. atanuiensis 259
LXXXIII. Local variation in Rhysoconcha atanuiensis, R. variumbilicata, and hybrid populations 261
LXXXIV. Rib variation in Rhysoconcha variumbilicata, R. atanuiensis, and hybrid populations 262
LXXXV. Frequency distribution of ribs/mm, in Ruatara oparica 269
LXXXVI. Rib variation in Ruatara oparica 271
LXXXVII. Local variation in Ruatara oparica 272
LXXXVIII. Rib variation in Orangia 283
LXXXIX. Local variation in Orangia 284
XC. Range of variation in Australdonta 291
XCI. Local variation in Australdonta 299
XCII. Range of variation in Taipidon 316
XCIII. Local variation in Taipidon 319
XCIV. Rib spacing and whorl diameter in Planudonta 337
XCV. Range of variation in Planudonta, Rikitea, and Nesodiscus 343
XCVI. Local variation in Nesodiscus 346
XCVII. Early whorl size in Nesodiscus 349
XCVIII. Local variation in Endodonta 370
XCIX. Ribs and rib spacing in Libera 388
C. Range of variation in Libera 392
CI. Early whorl diameter in Libera 393
CII. Local variation in Mangarevan Expedition Libera 395
CIII. Local variation in Society Island Libera 409
CIV. Island variation in Libera fratercula 420
CV. Local variation in Libera fratercula 421
CVI. Local variation in Libera subcavernula, L. tumuloides, and L.jacquinoti 429
CVII. Range of variation in Gambiodonta 433
XII
CVIII
Local variation in Gambiodonta.
443
CIX
Range of variation in Thaumatodon and Zyzzyxdonta
445
ex.
Local variation in Thaumatodon and Zyzzyxdonta
454
CXI
Range of variation in Aaadonta
469
CXII.
Percentage of adults in Aaadonta
470
CXIII.
Distribution of Aaadonta
472
CXIV.
Local variation in Aaadonta...
....485
INTRODUCTION
The small, radially ribbed, usually flammulated
pulmonate land snails that dominate, in terms of
species numbers, the faunas of southern temperate
regions traditionally have been lumped into a single
family unit, the Endodontidae. Several family units
are involved and many genera cannot yet be assigned
to a particular family. In discussing various genera and
structures, I have found it convenient to use several
terms in a restricted fashion. These are:
charopid — member of the family Charopidae
charopinine — structure agreeing with the typical
Charopidae pattern
endodontid — member of the family Endodontidae
endodontinine — structure agreeing with the
typical Endodontidae pattern
endodontoid — having the general aspect of
several families
punctid — member of the family Punctidae
punctinine — structure agreeing with the typical
Punctidae pattern
Other terms either conform to standard malacological
usage or are defined in the text.
This is the first of two monographs on the
endodontoid land snails of Polynesia, Micronesia, and
Fiji. It reviews the larger and older of the family
groups, the Endodontidae. A second contribution1 will
cover the specifically less diverse and more recent
Punctidae and Charopidae, together with detailed
zoogeographic and faunistic analyses. Together these
papers are based on more than 26,000 specimens and
review 285 species-level taxa in 45 genera. Most of
these were previously unreported, with 84 per cent of
the genera and 54 per cent of the species described as
new (table I).
This survey, started in 1960, is incomplete, since
about 290 unnamed Hawaiian species-level taxa are
preserved in the collections of the Bernice P. Bishop
Museum (table II). The latter represent a monophylet-
ic radiation involving limited supraspecific, but exten-
sive specific level differentiation. Analysis of the
approximately 58,000 Hawaiian specimens would have
required far more time than was available. Hence
consideration of the Hawaiian fauna has been restrict-
ed to a brief synopsis of the 30 previously named taxa,
one new description, and sufficient dissections to place
these groups within the Endodontidae.
'Hereafter referred to as Part II.
In addition, collecting efforts on the Pacific
Islands are far from being comprehensive. A few hours
in 1970 on Thithia and Tuvutha Islands in the Lau
Archipelago of Fiji resulted in finding two new taxa,
Priceconcha tuvuthaensis and Thaumatodon
spirrhymatum (Solem, 1973d), that are only cross-
referenced in this study. Many islands in Lau have not
been collected on at all, the higher elevations of the
Society and Marquesan Islands have been in-
adequately sampled, and relatively fragmentary collec-
tions have been made on some islands of the Palau
Group. I suspect that these 573 species-level taxa of
endodontoid snails may represent only 75 per cent of
the fauna extant in 1900. Unfortunately, a high
percentage is now extinct through habitat alterations
by man, predation by accidentally introduced ants,
and possibly because of competition from introduced
snails.
These figures show that the endodontoid snails
are the most diverse land snail group found in the
Pacific, substantially surpassing in numbers the fa-
belled Hawaiian Amastridae (294 species and sub-
species, Zimmerman, 1948, pp. 99-100) and mainly
Hawaiian Achatinellidae (ca. 200 species, Cooke and
Kondo, 1960).
One other family-level grouping has an equally
wide distribution and shows high generic level diver-
sity. The zonitoid families Helicarionidae and Zoni-
tidae (H. B. Baker, 1938b, 1940, 1941) total 32 genera
with 266 Pacific Island species (H. B. Baker, 1941, p.
347). Compared with the 45 genera and 573 species
level endodontoid taxa, this is proportionately greater
generic differentiation and lower specific differ-
entiation. For the zonitoid taxa an average of 8.31
species/genus compares with an average of 13.2
species/genus in the endodontoid families. This un-
doubtedly reflects the fact that the zonitoids are
much more recent colonizers of the Pacific and
represent a greater number of colonizing stocks. There
has been less time for local differentiation. Seemingly
there has been a greater niche balance in terms of
colonizing stocks and hence less opportunity for
diversification.
Other families that are significant in terms of
species numbers on Pacific Islands include the Succi-
neidae, Pupillidae (sensu lato), Diplommatinidae, He-
licinidae, and Assimineidae. Probably each has about
150 species on the Pacific Islands. Generally, each
family shows only one or two major centers of specific
diversity: the Succineidae in Tahiti and Hawaii,
SOLEM: ENDODONTOID LAND SNAILS
TABLE I. - PACIFIC ISLAND ENDODONTOID TAXA
Endodontidae
Punctidae &
Charopidae
Subtotals
Genera
Known New
5 19
19
Species
Known New
81 88
i i— i *"»-!•
Subspecies
Known New
2 lU
38
126
131
21
TOTALS
257
23
I. Three species listed as new but not described are omitted.
Pupillidae in Hawaii, Assimineidae in the Mariana and
Caroline Islands, Diplommatinidae in Micronesia and
Fiji.
The great diversity found in the endodontoid taxa
has not been recognized previously because the group
has been virtually ignored during this century. Some
76 per cent of the described species were named prior
to 1890 (table III). Outside of a few radular sketches
published in the 1870's to 1890's, and partial dis-
sections of three Endodonta from Hawaii (Cooke,
1928), no anatomical information has been recorded in
the literature. The reasons for this are simple. The
species are very small (96.4 per cent are less than 7
mm. in maximum size), secretive inhabitants of litter
or may be found on moss-covered tree trunks in dense
and undisturbed forests. They are found only by the
most skilled collectors. Endodontoid snails are of no
known economic importance and are sparsely repre-
sented in even the largest museum collections of the
world.
My own interest in these taxa was sparked by the
recovery of Miocene to Pleistocene fossil endodontoid
snails from the deep-core drillings on Bikini, Eniwetok,
and Funafuti Atolls (Ladd, 1958, 1968). I had worked
on endodontoid species from the New Hebrides (Solem,
1959a) and examined the limited Polynesian material
in mainland American museums. Seeing the fossil
species suggested that a revision of the living
endodontoid taxa from Polynesia and Micronesia
might provide insights into the historical zoogeography
of that region, present a time dimension to the
colonization of the islands, and permit some observa-
tions concerning the rate of evolution in these island
populations. I was led to believe that perhaps 100
living species might be involved in such a survey.
Exposure to the vast collection resources of the
Bernice P. Bishop Museum soon wrought drastic
revisions in this program. The fossils barely show
species or species group differentiation from living
taxa, add only one major modification to a current
geographic range, and provide no significant data
concerning possible evolutionary rates (pp. 116-118).
The huge quantity of material, potentially 84,000
specimens of 573 species level taxa, soon led to quite a
different focus than simple species sorting and class-
ification formation.
Although the endodontoid snails do not show
determinate growth upon reaching sexual maturity,
there are distinct patterns of growth change (pp. 11-
12) that enable separation of adult from juvenile
examples. The many large sets and essentially
synchronic samples in the Bishop Museum suggested
that detailed meristic analysis of populational vari-
ation should replace the conchologically traditional,
non-statistical means of studying variability and in
delineating species. Most endodontoid snails have a
highly complex surface sculpture, show moderate
shape variation, and have a few to many complex
barriers within the aperture of the shell. Thus a
wealth of characters was available for study. Most of
this basic species level analysis was done during the
period in which phenetics enjoyed its youthful flush of
enthusiasm.
Since the previous classification of the Pacific
Island endodontoid snails dated from a checklist
(Pilsbry, 1893a) that used such dichotomies as "teeth-
no teeth" plus "rounded shell-angled shell" for generic
placement, the temptation to experiment with phyletic
clustering techniques could not be resisted. By this
stage of the study (mid-1960's), dissections had
indicated that at least two major groups were
represented in the fauna. These groups differed
strikingly in their anatomy, but showed equally
striking similarities in shell appearance. Several shells
INTRODUCTION
TABLE II. - HAWAIIAN ENDODONTOIDS
Previously
described
Genus
En do do nt a
Cookeconcha
Nesophila
•
9
IT
k
In Bishop Museum Collection
Number of Number of Number of
species subspecies catalogued
sets
Punctum
77-79
105
12
5-9
55
55
9
339
170
TOTALS
31
199-205
119
5,197
from widely separated archipelagoes were virtually
identical in overall appearance. Even microscopic shell
features appeared the same under 32-96 X mag-
nification, but the animals had totally different
anatomical structures. The computer programs avail-
able to me at that time did not allow use of characters
for which information was lacking in regard to certain
taxa. Hence only conchological variables and no
anatomical data could be utilized. Beautiful clusters of
conchological convergences from disparate areas (figs.
59-61) were produced by these phenetic attempts.
While this numerical dabbling did not produce a
usable classification and added few phyletic insights, it
did serve the extremely important functions of greatly
increasing the number of shell characters observed,
requiring me to systematically record the variational
state of each character for each species, to focus on the
patterns of change for various characters, and to start
systematically reviewing the effects of particular
character variations on the standard measurable shell
features.
A more important feedback came in correlating
shell variations as analyzed and recorded during this
phase of the study with anatomical variations dis-
covered during the dissections. Initial focus in the
dissecting was to sort out major groups, then to study
patterns probably indicative of generic clusters, and
finally to study the variations shown within a genus,
particularly in regard to sympatric congeners. A
second and much more critical phase of the anatomical
survey involved detailed analysis of the variational
TABLE III. - DATES OF SPECIES DESCRIPTIONS
Charopidae
Endodontidae
Hawaiian non-Hawaiian
1820's
2
1830's
1
181+0 's
b 5
1850's
3 3
1860's
5 8
1870's
1 16
1880's
3 18
1890 's
3
1900's
8
1910's
1920's
1930's
1
19*10 's
1950 's
2 .
I960 's
6
6
5
1
It
3
2
TOTALS
30
53
4
SOLEM: ENDODONTOID LAND SNAILS
patterns within organ complexes, and finally attempts
to determine probable directions of character change
in the various systematic units.
Perhaps a majority of the species was extinct
before this project started, and only 100 of 283 taxa
could be dissected. With the high degree of
conchological convergence noted above, a major
problem involved how to classify species whose
anatomy could not be studied. Fortunately, the advent
of scanning electron microscopy provided a tool that
enabled finding highly obscure but stable shell
features correlating with the major anatomical types
(pp. 30-37, 63-65).
Considerable time has been spent in dissecting
endodontoid taxa from Norfolk Island, Lord Howe
Island, New Caledonia, New Zealand, South America,
and South Africa in an attempt to determine: 1) the
names that should be applied to the Pacific Island
family units; 2) how closely the Charopidae are related
to the Endodontidae and if any transitional species are
still extant; and 3) what are the basic anatomical
patterns of variation in the Charopidae. While the
name problem is settled, at the present time the other
two problems are still unresolved.
Phyletic interpretations are received today with
greater enthusiasm when outgroup comparisons are
made with more primitive and presumably ancestral
taxa. The problems of circularity in reasoning are very
great when work is limited to discussion of trends
within the group or groups being reviewed. Attempts
to pinpoint taxa that might be ancestral to the
Endodontidae have met with a total lack of success to
date. Dissections of Succineidae, which many authors
recently have stated to be a primitive land snail,
suggested instead (Solem, 1969b, In press B) that this
is an advanced group belonging to the same suborder
as the endodontoid taxa, while dissections of several
orthurethran and mesurethran taxa demonstrated that
these have nothing in common with the anatomical
patterns of the endodontoid taxa and cannot be
considered ancestral to them (Solem, unpublished). At
present I can only state that the Endodontidae have
the greatest number of primitive features found in any
sigmurethran land snail. I cannot point to any land
snail family as being a possible ancestor to the
Endodontidae (pp. 102-104). Hence meaningful out-
group comparisons have not been possible.
What began as a zoogeographically oriented
faunistic survey changed drastically in orientation.
Analysis of the patterns in both conchological and
anatomical variations, scanning electron microscope
studies of shell and radular structure (Solem, 1972a,
1972c, 1973a, 1973b), revision of the family- level
classification for endodontoid snails (pp. 105-107), and
most of the new ideas concerning slug evolution plus a
revised ordinal-level classification of the stylom-
matophoran pulmonates (Solem, In press B) have
developed from these endodontoid revisions.
The above discussion outlines the goals and
evolutionary chronology of this study. Obviously many
aspects pursued involved use of many more characters
than are needed to enable keying out species or
characterizing genera. Several of these objectives are
discussed in subsequent papers or in the second
monograph. But documentation of these conclusions
requires that the basic data be readily available.
Computer programs are far more sophisticated than
those used in the earlier stages of this study and, in
particular, factor analysis could be expected to aid the
interpretation of this data. Neither computer time nor
personal computer competence is available for pur-
suing these aspects.
Equally important is the matter of species limits
in island organisms. For those accustomed to working
with continental faunas, the bewildering pattern of
diversity and the, at times, minute conchological
differences between species come as a surprise. Fewer
than 15 per cent of the previously described species
could be identified with one of the delineated
population complexes without direct comparison with
type or syntype specimens. Descriptions and illustra-
tions that focused on differentiating only a few among
many species were totally inadequate when the
percentage of total taxa available for study increased.
From many islands, such as Tahiti and Moorea, only
partial and preliminary single, high altitude collecting
transects have been made up to the present time.
Sampling of additional populations can be expected to
yield not only undescribed taxa, but populations that
will cause revision in some of the species concepts
outlined below, and add much additional data on
microgeographic variation. Detailed descriptions and
illustrations will greatly aid work on future collections.
Finally, a good proportion of the material reported
was collected from reasonably restricted stations that
are localized with as much precision as the lack of
man-made markers and inadequate maps permitted. It
will be possible, except where extinction has taken
place, to sample the same populations on an allochron-
ic basis. By recording the available data on variation
in local populations, as well as summary data on
species units, suggestions both as to the locations for
new field collecting and the interpretation of the
results from such field collections will be facilitated.
Hence the diagnoses, descriptions, and discussions
of taxa include far more data than is necessary to
separate related species at our current level of species
recognition and understanding of species limits. When-
ever a character or character complex was found to
show systematically significant variation between any
pair of species units, the state of this character was
recorded for each species in the family. For obvious
reasons, this has been limited to optically visible
conchological characters and such anatomical data as
was available for particular species. All data on which
statements concerning variational trends and charac-
INTRODUCTION
ter correlations are made thus have been recorded in
the systematic section and are readily available for
others to use in further analyses.
Particular emphasis in this volume is laid in
analyzing the variations in shell features and their
correlations with size and shape variations. Equivalent
patterns are found in the Charopidae, subject to
alterations correlated with shifts in ecology. Discussion
of the basic adaptive value of these variations is
deferred until the second volume to permit inclusion of
the full data.
Following a brief summary of previous reports,
material studied, and methods of analysis, the patterns
of morphological and ecological variation are reviewed.
Discussions of family level classification, probable
phylogeny and generic classification precede geograph-
ic keys and the main systematic review. A short,
preliminary zoogeographic analysis concludes this
report.
ACKNOWLEDGEMENTS
Success of this project has been possible only
because of work done previously by the late C.
Montague Cooke, Jr. and Yoshio Kondo. For 46 years
(Kondo and Clench, 1952) Dr. Cooke assiduously
amassed unparalleled reference collections of Pacific
Island non-marine mollusks at the Bernice P. Bishop
Museum, Honolulu. His own large collections from the
Hawaiian Islands resulted from 10 personal ex-
peditions. Much additional material resulted from the
activities of colleagues and amateurs inspired by his
example. During the 1930's, Cooke was responsible for
three expeditions to Polynesia (Mangarevan Ex-
pedition, 1934), Micronesia (Micronesian Expedition,
1935-1936), and Fiji (Henry G. Lapham Expedition,
1938). These trips provided the bulk of the material
upon which this report is based. The wealth of
preserved soft parts and shells resulting from these
efforts stands as a permanent monument.
Cooke never rushed into print with fragmentary
discoveries. His list of publications is comparatively
short. From 1939 to 1941 he spent considerable time
sorting the endodontid material into species, making a
few preliminary notes, and overseeing preparation of
illustrations by Yoshio Kondo. For a limited number
of species, he drew up preliminary descriptions of shell
features. Cooke preferred to let a project sit for several
years and thus benefit from more mature reflection.
He also was more interested in the Tornatellinidae.
These factors combined to shelve the endodontid work
in 1941. The magnificent revision of the Achatinellidae
and the Tornatellinidae published by Cooke and
Kondo (1960) resulted from Cooke's endeavors between
1941 and his death in 1948.
Without Cooke's efforts, this material would not
have been collected. Without his years of museum
work, it would not have been available for study.
Without his preliminary sorting and notes, my task
would have required at least two additional years.
Cooke's preliminary work had been restricted to
shell features. Descriptions had been written only for
Henderson Island, Mangareva, and the Tuamotu
species. In reviewing material from these areas, I
agreed with Cooke's species limits in most cases, made
minor changes in others, and completely altered some
species. While I take full responsibility for errors, I
wish to recognize Cooke's great contributions not only
through the taxa named after him, but by having the
species he wrote up in a preliminary fashion cited
subsequently as described by "Cooke and Solem," or
"Solem and Cooke" in cases where I altered species
limits. All published diagnoses and descriptions were
prepared by myself, but where so indicated, species
authorship should be cited as a joint responsibility.
Yoshio Kondo began collecting for Dr. Cooke
during the Mangarevan Expedition while he was a
crew member on the Islander. After the voyage he
served as assistant, then as collaborator and finally
became successor to Dr. Cooke. Kondo prepared
illustrations for most of the Mangareva, Marquesas,
Society, and Rapa Island species from 1939-1941. It
was at his urging and encouragement that this
monograph was started. During our work in Honolulu
from August through December 1961, Dr. Kondo
provided every facility and aid possible. Through his
cooperation it was possible to borrow both soft parts
and shell material for more detailed analysis and to
publish his prepared illustrations. Figures prepared by
Yoshio Kondo are indicated in the figure explanations
by "YK." I am deeply grateful for his help and
encouragement during all stages of this project.
The aid of the Bernice P. Bishop Museum in
providing working space, allowing study of materials,
and permitting publication of the many shell drawings
has been crucial. I am greatly in their debt.
Establishing the identity of previously described
species and reviewing the characteristics of extralimital
species referred to Pacific Island taxa occupied an
inordinate amount of time and effort. For assistance in
locating material and/or loan of specimens, I am
indebted to the following curators and institutions,
which are listed in chronological order of visits and /or
borrowings: Dr. A. W. B. Powell, Auckland Institute
and Museum, Auckland; Dr. R. K. Dell, National
Museum of Natural History, Wellington; Dr. Charles
Fleming, New Zealand Geological Survey, Lower Hutt;
Dr. D. F. McMichael, formerly of the Australian
Museum, Sydney; Mrs. Hope Black and Dr. Brian
Smith, National Museum of Victoria, Melbourne; the
late Charles Gabriel, Melbourne; the late Bernard C.
Cotton, South Australian Museum, Adelaide; Dr. A.
Zilch, Natur-Museum Senckenberg, Frankfurt-a.-M.;
Dr. E. Fischer-Piette, Museum National d'Histoire
Naturelle, Paris; Dr. A. Magne, Museum d'Histoire
Naturelle, Bordeaux; Dona Emilia Garcia San Nicolas,
6
SOLEM: ENDODONTOID LAND SNAILS
Museo Nacional de Ciencias Naturales, Madrid; Dr. E.
Tortonese, Museo Civico di Storia Naturale, Genoa;
Dr. Eugene Binder, Musee de la Ville, Geneva; Dr.
Lothar Forcart, Naturhistorisches Museum, Basel; Dr.
H. Burla and Dr. H. Jungen, Zoologisches Museum der
Universitat, Zurich; Dr. J. Knudsen, Universitetets
Zoologiske Museum, Copenhagen; Dr. Bengt Huben-
dick, Naturhistoriska Museet, Goteborg; Dr. Charlotte
Holmquist, Naturhistoriska Riksmuseet, Stockholm;
Mrs. W. S. S. van Benthem Jutting van der Feen, Dr.
S. van der Spoel, Dr. H. Coomans, Zoologisch Museum,
Amsterdam; Dr. C. O. van Regteren Altena, Rijksmu-
seum van Natuurlijke Historie, Leiden; Dr. W. Adam,
Institut Royal des Sciences Naturelles de Belgique,
Brussels; Mr. Norman Tebble, Mr. John Peake, and
Mr. S. Peter Dance, British Museum (Natural His-
tory), London; Dr. William J. Clench, Museum of
Comparative Zoology, Harvard; Dr. W. K. Emerson,
American Museum of Natural History, New York; Dr.
R. Tucker Abbott and Dr. Robert Robertson, Acad-
emy of Natural Sciences, Philadelphia; Dr. Harald A.
Rehder and Dr. Joseph Rosewater, National Museum
of Natural History, Washington; Dr. Juan Jose
Parodiz, Carnegie Museum, Pittsburgh; Dr. Vincent
Conde, Redpath Museum, Montreal; Mr. Allyn Smith,
California Academy of Sciences, San Francisco; Dr. A.
Rodger Waterston, Royal Scottish Museum,
Edinburgh; Mr. Colin Matheson, National Museum of
Wales, Cardiff; and Dr. A. Myra Keen, Stanford
University. While many of the institutions cited above
do not have material listed in this particular report,
their collections and materials have been indispensible
to its completion.
For assistance during field work in Tahiti, Samoa,
Fiji, New Caledonia, New Zealand, and Australia, I am
indebted in particular to Mr. Laurie Price of Kaitaia,
New Zealand, who collected on Rarotonga, Samoa,
Lord Howe Island, Norfolk Island, Lau Archipelago,
Viti Levu, New Caledonia, New Hebrides, and Tonga
in connection with this work; Dr. Pierre Cassiau,
Papeete; Mr. L. Devambez, formerly of New Caledonia
and Fiji; Mr. Michael Watt, Apia; Dr. A. W. B.
Powell; and Dr. D. F. McMichael.
I have been extremely fortunate in having the
services of several excellent illustrators. The work of
Miss Margaret Anne Moran (MM), Mr. Sander Heilig
(SH), Miss Marcia Oddi (MO), Mr. Samuel H. Grove
(SG), Miss Carole Wrigley (CW), Mrs. Claire Kryczka
(CK), and Miss Patricia Rill (PR) is gratefully
acknowledged. Together with the large nucleus of
drawings prepared by Yoshio Kondo (YK) for the late
C. M. Cooke, Jr., their efforts have enabled presenta-
tion of phylogenetic and morphological trend data in
an understandable form, and provided identification
aids far superior to optical photographs. Without their
contributions, the value of this studv would have been
greatly diminished. In particular, Miss Moran's assis-
tance has been invaluable. Mounting and labelling of
the figures, preparation of maps and graphs, and
mounting of the tabular material has been handled
quite competently by Mrs. Jane Calvin, Mrs. Dorothy
Karall, Mrs. Claire Kryczka, and Miss Marian Pahl.
Scanning electron microscope photographs have been
made at the American Dental Association, Chicago
and Alpha Research and Development Company, Blue
Island, Illinois. I am deeply indebted to Dr. Harvey
Lyon, Mr. John Lenke, Mr. George Najarian, and Mr.
John Brown for assistance and advice. Photographic
work by Mr. Ferdinand Huysmans and Mr. John
Bayalis has been invaluable.
Initial statistical analysis of the material mea-
sured during 1961 and 1962 was done by Mrs. Barbara
Solem and Mrs. Robin Napier. Subsequent data
processing by Mrs. Sandra Rendleman, Mrs. Rita
Mecko, and myself was required in preparation of
tabular material and study of material obtained more
recently. Most tabular material was collected into
final form and typed by Mrs. Rendleman and Ms.
Jayne Freshour.
Manuscript typing and proofreading by Mrs. Rita
Mecko, Mrs. Sandra Rendleman, Mrs. Dorothy Karall,
Mrs. Lynda Hanke, Mrs. Alice Burke, Mrs. Nancy
Kozlowski, Mrs. Paula Steele, Ms. Barbara Walden,
Ms. Jayne Freshour, Mrs. Sharon Bacoyanis and the
following students from Antioch and Wilson Colleges
— Victoria Leuba, Carl Sainten, Kam B. Louis, and
Jeanne Sinderman — is gratefully acknowledged.
Considerable technical assistance in mounting
jaws and radulae was provided by Mrs. Pamela Hall,
Ms. Barbara Walden, and Mrs. Lynda Hanke.
For patience in serving as a sounding board for
ideas and for many helpful suggestions during various
stages of this study, I wish to thank Dr. Yoshio
Kondo, the late Dr. H. B. Baker, the late Dr. Fritz
Haas, Dr. J. Felsenstein, and Mr. Henry Dybas.
Grateful acknowledgement is made to the Nation-
al Science Foundation whose generous support
through grants G-16419, GB-3384, and GB-6779 has
been instrumental in illustration preparation plus
needed museum study and the field work involved.
Receipt of Grant No. DEB 75-14048 from the National
Science Foundation enabled publication of this
monograph. The patience of Field Museum of Natural
History in permitting such a lengthy time investment
and exploration of so many side facets of knowledge in
the course of almost 12 years has been critical, while
their support in 1961-1962 of Barbara Solem through a
Dee Fellowship made the data gathering possible.
For expert and patient help with proofreading and
indexing, I am deeply indebted to Mrs. Sharon
Bacoyanis.
PREVIOUS STUDIES
The only summary studies of Pacific Island
endodontoid land snails are the check list and
descriptions of Pease (1871a), the collection of illustra-
tions and brief diagnoses assembled by Tryon (1887),
and the critical checklist and revised classification
presented by Pilsbry (1893-1895). Tryon's classification
was highly artificial and conservative. Pilsbry 's effort
was peripheral to his focus on the morphology of
helicoid taxa and phyletic revision of the higher land
snails. His treatment of the endodontoid taxa
obviously was hastily done, but contained several
significant advances in classification. It has served as
the basis from which the generic lists presented by
Thiele (1931) and Zilch (1959-1960) were derived.
After 1900, only the descriptions of Pilsbry and
Vanatta (1905, 1906), the nomenclatural catalog of
Libera by Ponsonby (1910), an extremely significant
anatomical survey of some Hawaiian species by Cooke
(1928), and the reports on fossil endodontoid taxa by
Ladd (1958, 1968), and Ladd et al. (1970) require
special mention. Other reports are simple compilations
of names in faunistic catalogues (Gude, 1913; Caum,
1928; Germain, 1932), scattered descriptions of one or
two species in faunal reports (Clapp, 1923; Cockerell,
1933; I. Rensch, 1937; Dell, 1955; Solem, 1960), or
reports on faunistic collections without descriptions
(Cooke, 1934; Aubert de la Rue and Soyer, 1958).
The available knowledge is essentially pre-1900,
with all the deficiencies for modern systematic
research that this implies. Fortunately, two of the
workers, Andrew Garrett and Albert Mousson, were
far ahead of their time in terms of systematic concepts
and recognizing the need for precise geographic
documentation. Garrett was an American missionary
stationed on a number of different South Pacific
Islands from the 1860's until his death in 1887. At first
he sent specimens to W. Harper Pease, a merchant in
Hawaii, who described a total of 17 species (Pease,
1861, 1864, 1866, 1867, 1868, 1870, 1871a), unfortunate-
ly, often with scant regard for locality data (Garrett,
1881, p. 390). Later Garrett started to do his own
describing, first in a pair of strictly descriptive papers
(Garrett, 1872, 1874), then in faunistic surveys of
Rurutu, Austral Islands (Garrett, 1879), the Cook
Islands (Garrett, 1881), Society Islands (Garrett, 1884),
Samoan Islands (Garrett, 1887b), Fiji (Garrett, 1887a),
and the Marquesan Islands (Garrett, 1887c). Including
eight species collected by Garrett but described by W.
Harper Pease, Andrew Garrett was responsible for 40
of the 128 previously known taxa. Not only were his
descriptions detailed and accurate to the limits of
optical viewing, but his extensive field experience was
reflected in his precise localization of species and many
observations concerning the degree of sympatry or
allopatry on the same island. Most zoologists ignored
such data until well into this century. Garrett's data
has been summarized below, but consultation of his
papers remains mandatory for anybody attempting
field work in the South Pacific. Garrett's views of
speciation were quite modern and few of his
conclusions based on field work have been modified by
subsequent studies. He was located far from the
museum centers of Europe and North America, so that
inevitable errors in synonymy occured, but these do
not lessen the substance of his contributions. The only
major limitation that can be placed on his work
concerns the apparent restriction of his collecting
efforts to reasonably low elevations. High-altitude
collections in the Marquesas by the members of the
Bishop Museum "Pacific Entomological Survey"
(Adamson, 1935, 1936), in the Society Islands by
members of the Mangarevan Expedition from the B. P.
Bishop Museum (Cooke, 1935, p. 51), and on Rar-
otonga by a Field Museum Expedition (Solem, 1972b)
have discovered many large and conspicuous species
unknown to Garrett and failed to find a high
percentage of his species. This suggests quite strongly
that his efforts were restricted to the lower forested
areas, whose fauna is now extinct, and that he did not
attempt to reach higher elevations in his collecting.
Albert Mousson never visited the South Seas. His
material was obtained from the Hamburg trading firm
Godeffroy, mostly as a result of the efforts by Eduard
Graeffe. The eight species described by Mousson (1865,
1869, 1870, 1871, 1873) are carefully delineated, well
illustrated and accompanied by detailed locality data.
His faunal accounts of species from Fiji, the Ellice
Island, Tonga, and Samoa are inferior to Garrett's
only because field observations are lacking.
The faunal report on the Caroline Islands by Otto
von Mollendorff (1900) and the paper on Guam species
by J. Quadras and Mollendorff (1894) are quite
competent, as are the many Philippine studies that
included the description of one endodontid
(Mollendorff, 1888). The 11 species named in these
studies are almost equaled by the 10 described by C. F.
Ancey (1889a, b, c, 1899, 1904). Most of these are from
Hawaii, and are briefly mentioned below. The two
8
SOLEM: ENDODONTOID LAND SNAILS
Libera from the Society Islands and the single species
from Mangareva were recognizable from his descrip-
tions. The summary of Hawaiian land snails by Ancey
(1889d) formed the basis for the more familiar
compilations of Baldwin (1893), Sykes (1900), and
Caum (1928), although it is infrequently cited today.
From a wide variety of sources and localities, L.
Pfeiffer (1845, 1846a, b, 1850a, 1853a, 1856, 1858, 1859a,
1862) named nine species. Otherwise there are the
scattered descriptions of Ferussac (1824, 1840), Anton
(1839), Hombron and Jacquinot (1841), Gould (1844,
1846a), Mighels (1845), Reeve (1851-1854), Cox (1870),
Semper (1874), Liardet (1876), Tapparone-Canefri
(1883), Tryon (1887), Beddome (1889), Sykes (1896), E.
A. Smith (1897), Pilsbry and Vanatta (1905, 1906),
Clapp (1923), Cockerell (1933), Dell (1955), and Solem
(1959b, 1960).
To summarize the above data, Table III indicates
the dates of description for the species recognized as
valid in this study. It is obvious that the major
contribution occurred between 1860 and 1890, when 57
per cent of the species were named. This is the primary
period of activity for Pease, Garrett, Mousson, and
Ancey, who account for 52 per cent of the previously
named species. Since 1910, only 10 per cent (13 species)
have been named, and all of these are fossil or
extralimital to the main area of study. As indicated
above, essentially no faunistic collecting was done
except by the Bishop Museum program from the time
of Mollendorff to the start of this study.
Not only little faunal data accumulated, but there
was practically no data recorded concerning the
anatomy of endodontoid taxa from the Pacific Islands.
Semper (1874, pp. 135-136, pi. 16, fig. 18) figured the
central radular tooth of a Tahitian specimen identified
as Libera bursatella and briefly discussed the cusp
structure. W. G. Binney (1875, p. 248, pi. 21, fig. 6)
illustrated several teeth and recorded the radular
formula of the Rarotongan Libera tumuloides (Gar-
rett) as 10-7-1-7-10. Subsequently, W. G. Binney (1885,
pp. 88-89, pi. 2, figs. L-N) figured and briefly discussed
the radulae of Libera tumuloides (Garrett), Nesodiscus
huaheinensis (Pfeiffer) (formula 12-6-1-6-12), and
Mautodontha parvidens (Pease) (formula 7-4-1-4-7) as
"Endodonta incerta Mousson," a nude name under
which this species has been widely distributed in older
collections. Pilsbry (1893-1895, p. 23, pi. 9, fig. 34)
illustrated the radular teeth of Libera recedens
Garrett. No information concerning other anatomical
features were recorded until the work of Cooke (1928)
on three species of Endodonta from Oahu, Hawaiian
Islands. Unfortunately, this excellent paper has been
overlooked or misinterpreted by subsequent authors.
Considerable information has accumulated
concerning the external anatomy and radular struc-
ture of Australian and New Zealand taxa, primarily
through the efforts of Charles Hedley (1891, 1893a)
and Henry Suter (1890, 1891a, b, 1892a, b, c, 1893a, b,
c, d, 1894a, b, c, d, 1901, 1903, 1913). Recently Frank
Climo (1969a, b, 1970, 1971a, b) has published several
revisions of New Zealand taxa utilizing genital
anatomy in addition to shell and radular features. His
work presents a large quantity of useful data and
important observations, but as outlined below (pp.
106-108), we have very different interpretations of
character weighting and phylogeny.
Prior to this study a high percentage of the species
was unknown, and virtually no anatomical in-
vestigations, no study of interpopulational variation,
and only limited ecological information were available.
As documented on pp. 118-119, classification was still
based on convenient "either-or" pigeon holes. Hence
not only has it been necessary to do much work that
is already accomplished for better-known groups, but
the hunt for criteria to use in species recognition and
clustering has been quite time consuming. The lack of
previous work also necessitates considerable prelimi-
nary discussions concerning the characters used and
their validity as "key" criteria.
MATERIAL STUDIED
As summarized in Table IV, some 26,000 speci-
mens were studied in detail. Perhaps an additional
6,000 specimens, mainly involving sets with mixed
species and localities that originated from the W.
Harper Pease collection, were examined quickly, but
neither measured nor listed. Pease himself was careless
in handling his collection, noting in a letter to a
correspondent that his small daughter delighted in
playing with shells in the cabinets (Alison Kay, pers.
comm.). In addition, many years later during shipment
of Pease's collection from England to Harvard Univer-
sity, apparently there was extensive mixing of sets
when cabinets were tilted and handled. In subsequent
years, these shells have been traded widely to other
museums and amateur collectors. Virtually all traded
Pease material that I examined contained more than
one species, often living on different islands.
While for the non-Hawaiian Endodontidae, the
material examined per species-level taxon averaged
120.3, for the Charopidae it was only 75.9 speci-
mens/species-level taxon. It is difficult to decide
exactly how much of this is caused by artifacts of
collecting and how much results from a true difference
in relative abundance. The charopid taxa include a
number of species from Melanesia and Indonesia, areas
in which there has been far less intensive land snail
collecting activity. Charopids also include more species
from islands such as Niue, Rotuma, and various of the
Ellice Islands where collections were made by non-
malacologists and hence lower quantities of materials
obtained. These factors probably reduced the average
number of specimens by about 10. On the other hand,
in the outer Polynesian Islands the Endodontidae were
perhaps the dominant ground stratum snail. Where
still extant, they can be collected in quantity from
limited areas. In contrast, the charopids from the big
islands of Fiji and Samoa, for example, are far less
TABLE IV. - SUMMARY OF MATERIAL STUDIED
Endodontidae
Hawaiian
non-Hawaiian
Punctidae
Charopidae
TOTAL
Species
Level Taxa
31
2
96
283
Specimens
Examined
238
18,530
1
7,288
26,063
abundant than many helicarionids and rarely have
been collected in any quantity. On some of the
Micronesian Islands apparently the charopids locally
are as abundant as many of the Polynesian Endodon-
tidae. Probably in the Melanesian-Fiji area the
charopids are not abundant under any circumstances.
Certainly the charopids with apertural barriers of Fiji,
Tonga, Samoa, and neighboring islands could only be
classified as rare. Punctids are a marginal group in the
area of study.
Hence the differing material per species numbers
reflect both differential abundance and bias in collec-
ting. Table V summarizes the abundance data on a
slightly more refined basis. The rarity aspect of some
charopid taxa shows very clearly in the increased
number of species known from 1-3 specimens and
decreased 4-8 specimen grouping. Otherwise the per-
centage distributions are quite comparable. Data
concerning species abundance on particular islands
will be presented in the zoogeographic analysis
accompanying Part II of this monograph.
With the exception of pre-1900 species that have
not been collected subsequently, the listing of speci-
mens examined is confined to adequately localized and
measured materials. Throughout the text the following
abbreviations indicate the repository of the specimens:
AMS Australian Museum, Sydney
ANSP Academy of Natural Sciences, Philadelphia
BMNH British Museum (Natural History), London
BPBM Bernice P. Bishop Museum, Honolulu
Brussels Institut Royal des Sciences Naturelles de Belgique,
Brussels
Cardiff National Museum of Wales, Cardiff
FMNH Field Museum of Natural History, Chicago
MCZ Museum of Comparative Zoology, Harvard University
Paris Museum National d'Histoire Naturelle, Paris
RSM Royal Scottish Museum, Edinburgh
SMF Natur-Museum Senckenberg, Frankfurt
USNM National Museum of Natural History, Washington
Zurich Zoologisches Institut der Universitat, Zurich
Most of the material studied was in the Bernice P.
Bishop Museum. In addition to samples of Garrett's
and Ancey's materials from the last century, Cooke
had assiduously accumulated materials from various
Pacific Islands. E. H. Bryan and Y. Kondo collected
extensively on Guam, P. H. Buck from some of the
Cook Islands, Cooke and Wray Harris in American
Samoa, and Harry Ladd brought back highly sig-
nificant collections from some of the Lau Archipelago
in Fiji. But it was the three expeditions sponsored by
Bishop Museum in the 1930's that were most
10
SOLEM: ENDODONTOID LAND SNAILS
TABLE V. - FREQUENCY DISTRIBUTION OF SPECIMENS
EXAMINED PER SPECIES LEVEL TAXON
Number and Percent of Species
Endodontidae Punctidae & Charopidae
Number of Hawaiian non-Hawaiian
Specimens
06-
1-3
l*-8
9-19
21-60
61-100
101-260
300-882
1,000-1,900
TOTALS
6 22(lU. 3%)
10 29(18.8%)
7 2l*(15.6%)
2 33(21.1*%)
13(8.1*%)
19(12.3%)
9(5.8%)
5(3-2%)
31 151*
22(22.1*%)
7(7.1%)
13(13.3%)
26(26.5%)
8(8.1%)
17(17.3%)
!*(!*.!%)
1(1.0%)
productive. The Mangarevan Expedition from April 15
through October 28 in 1934 (Cooke, 1935), the
Micronesian Expedition from December 8, 1935 to
June 10, 1936 (Gregory, 1936, p. 40), and the Henry G.
Lapham Expedition to Fiji from June 27 through
September 28, 1938 (Buck, 1939, pp. 29-30) provided 70
per cent of the material on which this monograph is
based.
The intensity of collecting can be indicated by the
statement of Cooke in Gregory (1936, p. 15) that
37,593 land snails were collected on Rapa and 30,695
on Mangareva during the Mangarevan Expedition.
Much of the field work on Rapa was accomplished
under abominable weather conditions (Zimmerman,
1938, pp. 3-4), and on only a portion of the 31-day stay
was "full day" effort possible. The magnitude of these
collections is awesome. The focus of malacological
collecting was "On the trail of the Tornatellinidae"
(Kondo and Clench, 1952, p. 17). The endodontoid
snails were a very secondary consideration. Despite
this the 4,078 Rapan endodontids are 10.8 per cent of
the material collected, while the 2,274 endodontids
from Mangareva are 7.4 per cent of the total shells.
Most of the material was collected within a four-
year period. The same people, C. M. Cooke, Y. Kondo,
and E. Zimmerman, gathered the bulk of these
collections. The collectors, collecting techniques, and
field procedures were the same, so that comparisons of
abundance and local distribution between archi-
pelagoes are possible.
Curatorial methods at the Bishop Museum differ
from those used elsewhere and require some ex-
planation. As is customary, new field collections from
single stations are sorted into species. Whereas most
museums would assign a different catalogue number to
each set, i.e., all material of one species collected at
one locality at one time, each lot of the Bishop
Museum mollusks is sorted in several growth stages —
adult, paraneanic, metaneanic, ananeanic, and embryo
(see Pilsbry and Cooke, 1914-1916, pp. x, xi for stage
definitions). Each stage is given a separate, but usually
consecutive, catalogue number. Sometimes gerontic
individuals, unusual color or shape variations are
segregated under yet other numbers. Thus what would
be given a single number in most other museums, may
have as many as 10 different numbers in the Bishop
Museum collection.
Soft parts are extracted from each shell by means
of a water jet (Kondo and Clench, 1952, pp. 27-28) and
material from one set is stored in tiny homeopathic
vials. The latter are grouped into pint jars and shelved
in numerical sequence. The dried shells are housed in
small pill boxes, generally 11A inch in diameter, with
up to 48 such pill boxes placed in a covered cardboard
tray. The latter are stored in open stacks. Only the
catalogue number and a very abbreviated locality are
with the specimens. Continual reference to the
catalogue and field note books is necessary to retrieve
full locality and ecological information.
This is a highly efficient and effective system of
housing and storing quantities of minute material,
keeping dry and alcohol storage separate, and enabling
age-class recognition of anatomical material. With
species under the size of perhaps 5 mm. this system
causes little difficulty. With larger shells, the limita-
tions of space within individual pill boxes tend to
produce bias in sorting. Invariably the gerontic and
larger adult individuals are clustered separately from
the adults that are closer to average in size. "Large"
and "average" adults have separate catalogue num-
bers. Measurements of such species as Nesodiscus
fictus, many Endodonta, Libera bursatella bursatella,
and the larger Gambiodonta had to take this sorting
bias into account.
In total some 80 per cent of the specimens cited
are from the Bishop Museum collections. Perhaps half
of the remaining is either from the Field Museum
collections or was obtained by myself and Mr. Laurie
Price of Kaitaia, New Zealand for this project. My own
collecting has been limited to Tahiti, Viti Levu, Upolu,
New Caledonia, New Zealand, and Australia, while Mr.
Price, over a series of years, has made collections from
Lord Howe Island, Norfolk Island, Rarotonga, Upolu,
Savaii, several islands of Tonga, New Hebrides, Viti
Levu, Lau Archipelago, New Caledonia, and several
parts of Australia. These collections are housed in
Field Museum. The Lau collections were received too
late to be other than cross-referenced in this study.
The non-Polynesian collections have provided exten-
sive comparative material on which most of the higher
classification decisions have been based. The rest of
the material studied consists of type specimens,
remnants of the Garrett, Mousson, and Ancey collec-
tions, plus an occasional previously unstudied field
collection and the subfossil to fossil species recorded
by Ladd U958, 1968) and Aubert de la Rue and Soyer
(1958).
METHODS OF ANALYSIS
Island taxa bring both advantages and dis-
advantages to evolutionary studies. Particularly wher-
ever the rate of immigration and species turnover is
low and the opportunity for in situ speciation is thus
enhanced, the possibilities of detecting convergences in
structure between taxa on different islands or island
groups are relatively good. Continental areas have
been subject to the repetitive ebb and flow of faunal
migrations, particularly in regions subject to the
effects of the Pleistocene glaciation. Faunas of these
areas usually are composed of multiple introductions,
while the more isolated islands may have virtually
monophyletic adaptive radiations. As is discussed
elsewhere (Solem, 1973e), the Pacific Island land snails
give evidence of low migration and high local speci-
ation rates.
Several situations were encountered where species
from widely separated archipelagoes appeared virtually
identical in many shell features. Deeper analysis of the
structures and how they are formed enabled recogniz-
ing that these similarities were convergent, although
phenetic clustering techniques grouped them together.
In several ways this study departs from the
normal systematic criteria and methodology as cur-
rently applied to mollusks. Far more statistical
analysis of variation is utilized; an attempt is made to
specify the philosophy used in recognizing species; and
discussion of variational trends within generic units
focuses on departures from an "ideal generalized
morphotype" of that unit. Explanation of these
procedures is a necessary prelude.
VARIATION IN ADULT SHELLS
Few people have attempted to undertake statisti-
cal analysis of variation in shells of molluscan species
that do not show determinate growth, such as usually
is indicated by a reflected lip and/or denticles. It has
been assumed that growth would continue throughout
life and hence age factors would seriously bias or
obscure any pattern to size or shape variation. In the
zonitoids "...growth is usually persistent; that is, most
species become sexually mature when comparatively
small but continue to add whorls almost indefinitely"
(H. B. Baker, 1938b, pp. 5-6). Thus Baker picked
certain standard whorl counts and listed the size
reached at these marker points to indicate size
differences between species.
Early in this study it became evident that
postembryonic shell growth in the endodontids
consists of two phases. For the first few whorls there is
continuous growth, but then an alteration in pattern
occurs that affects several features. In most taxa these
changes are highly correlated, begin abruptly, and
could be easily identified even by new
assistants after an hour or so of instruction. These
changes involve the pattern of rib deposition, umbilical
decoiling, lip callus formation, and body whorl des-
cension. The ribs become more crowded and/or
irregular in spacing, often are reduced to a point at
which they cannot be counted, and the microsculpture
essentially disappears. The umbilicus becomes notice-
ably wider for a period of growth, then the umbilical
lip suddenly may reflect slightly in toward the center
of the umbilicus. At the same time, the inner lip
margin, particularly on the columellar wall, becomes
greatly thickened, frequently with a thick callus,
whereas in juvenile shells it is thin and sharp edged.
The edge of the parietal callus may thicken and the
apertural barriers become slightly wider at their
anterior end. Finally, starting with the change in rib
deposition, there is a tendency for the body whorl to
descend more rapidly. These changes are obvious in
most species. A notable exception involves those
species whose growth pattern results in a small
umbilicus, reduced sculpture, and thick apertural
callus at all stages. In these species the juvenile
growth is virtually the same as adult growth. Not
every species shows all of the changes cited above and
some alterations may occur before others. Never-
theless, in only 1-2 per cent of the specimens is a
judgment decision needed concerning whether a speci-
men is showing juvenile or adult growth. The adult
growth may occupy as much as one-quarter of a whorl,
very rarely three-eighths of a whorl. There are
considerable differences as to when it starts. Some
individuals may start "adult" growth more than three-
quarters of a whorl earlier than others.
Such a change in growth pattern generally is
correlated in animals with the onset of reproductive
activity. Until that point, energy is channeled into
increasing the size of the individual. Afterwards it is
channeled into producing the next generation. Because
the Bishop Museum mollusk collection is stored with
the animals removed from the shell, it was not possible
to study the timing link between reproductive matur-
ity and these growth changes by dissecting individuals
whose shell characters had been recorded. The only
shell- associated endodontids available to me in
quantity were Thaumatodon hystricelloides from
11
12
SOLEM: ENDODONTOID LAND SNAILS
WHORL COUNT IN ADULTS
85-
80-
75-
70-
65-
60-
55-
C/5
§50-
CO
£40-
m
=,30-
25-
20-
15-
10-
5-
7 ' X
WHORL COUNT
FIG. 1. Frequency distribution of whorl counts in adult Libera
fratercula from quantitative samples.
Western Samoa, a species that shows very few adult
changes, and Libera fratercula from Rarotonga, in
which the formation of a brood chamber in the shell
after reaching reproductive maturity is yet another
modification.
Shells showing a "juvenile" pattern of growth can
be segregated from those that have a presumed
"adult" growth pattern. The significant question in
terms of analysis is what distribution of meristic
features is shown by the "adult" specimens. Data from
a quantitative sampling of live Libera fratercula from
Rarotonga have been summarized by Solem (1969a).
In the present paper data are given on grouped
variation in all live adults. Of some 623 living snails,
219 juveniles and 391 adults could be measured. The
others showed repaired breaks in the shell or were
otherwise unsuitable for analysis. Figures 1-4 graph
the variation in whorl count, height, H/D ratio, and
shell diameter, respectively. Except for the diameter,
these agree with Quetelet's principle in distribution of
the size classes. The diameter is affected by the fact
that after the start of reproductive activity in this
species, the snail grows and gradually narrows the
umbilical opening to form a brood chamber. During
this growth the shell diameter often remains stable.
Hence the skewed nature of the diameter curve. The
whorl count is symmetrical, but the height curve is
skewed positively, reflecting the continued growth
during adulthood to narrow the umbilical opening.
Smaller samples of other species show the same
pattern, that of a normal distribution with at most a
slight positive skewing, particularly in regard to rib
counts (p. 42). I thus assume that measurements of
adult shells will show either a "normal" distribution or
slight positive skewing and hence can be compared
through standard statistical analysis. The absence of
determinate growth does not seem to have affected the
basic normal distribution of adult variation in measur-
able and continuously variable shell characters, thus
interpretation of variation is based heavily on statisti-
cal data concerning adult variation.
Nature of quantitative data presented
Basic quantitative data are presented in two
formats. First, there is a summary of variation in size,
shape, and apertural dentition for each species of that
cluster. These tables are headed "Range of variation in
." The second format records adult size and
shape variation within either specific local populations
(where such refinement of collecting data is available)
or particular museum sets (either single sets or
material originating from the same collection) in the
case of specimens dating from the late 1800's. These
tables are captioned "Local variation in ." Unless
stated otherwise in the discussion of a particular
HEIGHT IN ADULTS
95-
90-
85-
80-
75-
70-
65-
60-
55-
50-
45-
40-
35-
30-
25-
20-
15-
10-
5-
Fio. 2. Frequency distribution of shell height in adult Libera
fratercula from quantitative samples.
METHODS OF ANALYSIS
13
species or set, all measurements were made only on
adult and gerontic individuals.
In the tables summarizing range of variation,
certain items require explanation. The number of
specimens examined does not refer to the number of
measured adults, but rather to the total number of
specimens, both adult and juvenile, available for this
study. For the ribs, height, diameter, Height /Diameter
ratio (hereafter H/D ratio), and Diameter/Umbilicus
ratio (hereafter D/U ratio), the first figure is the
simple arithmetic mean of all measured adults. This is
followed in parenthesis by the range. For the whorl
counts, the cited range omits + and — signs. Where
species have been collected again in recent years, these
measurements summarize data from many snail
generations apart. Under these circumstances, calcu-
lation of variance would serve no useful purpose.
Definitions of the apertural barriers are given
elsewhere (p. 53). In the summary tables, Pr means
parietal, C columellar, and P palatal. In each case, the
numbers before the + sign refer to major barriers, the
numbers following to minor traces. Where size reduc-
tion is involved, recognition of this difference involves
considerable subjectivity. Where such arbitrary divi-
sions were made, they are discussed in the text.
Variation in barrier numbers is indicated in two ways.
Two numbers connected by a dash (i.e., 3-4) indicate
DIAMETER IN ADULTS
H/D RATIO IN ADULTS
90-
85-
80-
75-
70-
65-
60-
55-
50-
45-
40-
35-
30-
25-
20-
15-
10-
5-
65-
60-
55-
50-
45-
40-
35-
30-
25-
20-
15-
10-
5-
T
T
500
600
800
Fid. 3. Frequency distribution of Height/Diameter ratio in adult
Libera fratercula from quantitative samples.
FIG. 4. Frequency distribution of shell diameter in adult Libera
fratercula from quantitative samples.
that at least one-third of the individuals have the less
frequent state. If one of the numbers is underlined
(i.e., 3-4), this means that the underlined number is
found in less than one-third of the individuals
examined. Usually it means a rare to infrequent
character state. Occasionally, a number such as .2_-3-4_
+ 4_-6 may be seen. This is translated as usually 3
major barriers, rarely 2 or 4; normally with six
accessory traces, rarely only four.
In the tables documenting variation within local
populations or single museum sets, the number of
specimens refers to those actually measured. For the
whorl counts, only the mean and range is given, since
the measuring error is relatively large (p. 15). For the
other parameters, mean, standard error of the mean,
and range are given in that sequence, for example —
4.32 ± 0.036 (3.97-4.46).
Sample bias
The material in the Bishop Museum collected by
Cooke and Kondo, plus the specimens in Field
Museum of Natural History collected by Solem and
Price, provide samples undistorted by subsequent
museum activities. In the case of specimens from the
Garrett and Mousson collections, we are dealing with
small remnants of initially large sets. Specimens were
traded in driblets of two or three to other collectors in
exchange for species new to the trader. Those samples
remaining in the Mousson and Garrett material are
size biased. I have shown elsewhere (Solem, 1966b, p.
16) that such trading often will result in elimination of
smaller shells from the sample, thus increasing the
mean size significantly. This was especially noticeable
in several species of Libera during this study, but even
14
SOLEM: ENDODONTOID LAND SNAILS
in the case of the 3-5 mm. endodontids, trading seems
to have resulted in size bias. Hence only very cautious
conclusions have been drawn from comparison of
samples collected during the 1800's with material
collected during the 1930's.
A seldom appreciated collecting phenomenon
involves unconscious field bias towards selecting larger
or "adult" specimens and neglecting the smaller,
possibly juvenile individuals. This has been docu-
mented by H. B. Baker (1962b, p. 22) for North
American Allogona and Puerto Rican pomatiasids. I
have experienced this personally in relation to Pan-
amanian Mexcyclotus and Samoan Ostodes. It is seen
in this study with sets of Libera bursatella orofen-
ensis. This difficulty is greater in those forms that do
not have a cessation of growth that is marked by
reflected lip formation at "adulthood." A strong bias
towards gerontic and adult shells with a distinct
neglect of subadult and juvenile specimens is quite
possible, particularly when secondary interest is at-
tached to the group, as in collection of snails by
botanists or herpetologists.
Although they were not collected on a randomized
or quantitative basis, material accumulated during the
several Bishop Museum expeditions seems to have
avoided such a bias. Most sets contain a broad mixture
of age groups. I could detect very little evidence of
selection for adults in the collecting process, and then
only in species taken by non-malacologists. The
collections were not quantitative samples, however,
and only a few sets were large enough to infer data on
population structure. The reason for the probable lack
of sample bias stems from the purpose of the trips. The
collectors were primarily concerned with obtaining
members of another family, the Tornatellinidae
(Kondo and Clench, 1952, p. 17). Even in this group,
they were attempting to gather all specimens seen,
rather than to take a "good sample" of the popu-
lations. Since 1 ) the small endodontids previously were
essentially unknown; 2) they are very difficult to
distinguish without use of a microscope; and 3) no
particular emphasis was placed on the family by the
collectors, I am convinced that there is minimal bias in
the material.
Measurement reliability
All measurements of the shells were made by me
under a Leitz stereoscopic dissecting microscope, using
an 8 X ocular, 1 X , 2 X or 4 X objectives and an ocular
micrometer. The micrometer was calibrated with a
stage micrometer at several different times during this
study. No significant differences in the calibration
readings were noted. Measurements were taken to the
nearest 0.5 micrometer unit. For the different objec-
tives, one micrometer unit equals: 0.131 mm. with the
Ix objective; 0.0658 mm. with the 2x objective; and
0.0329 mm. with the 4x objective. Most specimens
were measured using the 2 X objective. Sets with most
or all specimens under 2.75 mm. in diameter were
FIG. 5. Method of measuring specimens. A-B, shell diameter; C-
D, shell height; E-F, spire protrusion; F-G, body whorl width; H-I,
umbilical width.
measured with the 4x objective and sets with most
specimens over 5.00 mm. in diameter were measured
with the 1 X objective.
Accuracy of measurement was tested by remeasur-
ing individuals in several small sets five times over a
four-year period. No reference was made to previous
measurements before or during each trial. It was
possible to compare specimen with specimen rather
than having to depend on means, since there was a
METHODS OF ANALYSIS
15
wide size range within these sets. Reproducibility of
the measurements varied with the parameter. Ba-
sically standard measurements were used and taken as
indicated in Figure 5. Greatest accuracy was obtained
in measuring the diameter, least in making the whorl
count. The diameter rarely (less than 5 per cent)
varied more than 0.5 units in a measurement of 40-50
units or 1 unit in 80-90, an accuracy of 1.0-1.25 per
cent. The more subjective height measurement showed
a greater range of from 1 unit in 35-50 to 1.5 units in
65-70— an accuracy of 2-2.9 per cent with the heights
measured in fewer units being less accurately recorded
than those in larger numbers. Determination of
umbilical width varied inversely with the size of the
umbilicus— the wider the umbilicus, the more accurate
the measurement. For very narrow umbilici, those
whose D/U ratio was more than 7, but less than 10,
error was in the range of 8-12 per cent. For those with
tiny umbilici, D/U ratio 10-30, errors of 25-50 per cent
were present, since often only one or two units were
measured with an error of 0.5 units. The wider
umbilici, D/U ratios 2-4, could be measured to within
a 2-5 per cent error. Rib counts (fig. 32) were accurate
usually to within one rib in 50, two in 100 and up to
six for over 200 ribs— generally a 2 per cent error
except where the ribs were very fine and numerous,
which often resulted in a 3 per cent error. Most of
these errors resulted from judgment decisions
concerning rib status at repaired breaks or on gerontic
growth sections. Whorl counts normally showed a Vs
error, with estimated readings made to the nearest
one-eighth. For this reason, no statistical treatment of
whorl counts was attempted. Usually species differ-
ences in this category were either quite pronounced or
not noticeable.
The margin of possible error in the basic measure-
ments naturally affects the accuracy of calculated
ratios. Particularly in regard to the higher D/U ratios,
the actual numbers become virtually meaningless.
These figures only serve to indicate the small nature
of the umbilicus and are worthless for statistical
comparisons. Use of the lower D/U ratios is possible
with a higher degree of confidence. Calculation of D/U
ratios, using the margins of error cited above and
arbitrarily selected figures, produced a range of
possible error from 6.5-6.8 per cent in the 2-4 D/U
ratios and from 7.6-14.3 per cent in the 7-10 D/U
ratios. Calculation of sample H/D ratios produced a
possible range of error between 3.3 per cent and 3.8 per
cent. It must be stressed, however, that these margins
of error represent the calculated extremes. It was not
thought worthwhile to determine the mean margin of
error in measuring individual specimens, but for three
samples that had been measured several times, I
computed the means for H, D, H/D, and D/U. With 7
to 11 specimens involved, the sample means varied by:
H - 0.4-0.7%;
D -0.1-0.3%;
H/D - 0.5-1.0%; and
D/U - 1-2% for ratios less than 8.
In making comparisons between samples, the
above figures have been given considerable weight in
deciding whether calculated differences are significant,
or represent random variation.
CRITERIA FOR SPECIES RECOGNITION
Recognition of species on the same island presents
a different problem from dealing with allopatric
populations on different islands. Closely related sym-
patric species must have "species recognition" features
to maintain genetic integrity. These differ with the
group of organisms. Where congeneric species of
endodontid snails are sympatric to the extent of living
under the same log, character displacement in termi-
nal genital structures has occurred (tables LII-LIV).
One repetitive type of such character displacement is
for the normal pattern of two penial pilasters that are
equal in size to become altered. One of the species will
have the conservative pattern, while in the other, one
pilaster will be greatly reduced. Examples of this are
seen in Libera micrasoma (fig. 171h, two simple
pilasters) and L. cookeana (fig. 172a, two unequal
pilasters) from Station 865 on Tahiti and in most of
the Rapan Opanara where there are extensive and
complex sympatric-allopatric species groupings. An
interesting variation is seen in the Marquesan Taipi-
don, where T. fragila (fig. 138f) and T. varidentata
(fig. 138h) on Hivaoa and T. centadentata (fig. 139f)
and T. semimarsupialis (fig. 139b) on Nukuhiva are
sympatric or the handful of known specimens have
been collected on the same ridge in different years
within 90 ft. recorded elevation. In each case the first
species has the pilasters broken up into a series of
longitudinally arranged tubercles, while the second
species retains the "typical" pattern for that genus. In
the Nukuhiva Planudonta intermedia (fig. 147b) the
4.6 mm. long penis has two pilasters that are almost
circular in cross-section, while the probably sympatric
P. concava (fig. 147d) has one pilaster of the 6 mm.
long penis altered into a high folded ridge.
Where more than one genus from a monophyletic
assemblage and several species are sympatric, as on
Rapa Island, there are changes in size of penis, number
of pilasters, shape of pilasters, and the length of the
penial pilasters. Data on these alterations are given in
the generic discussions and in Tables LII-LIV. They
are not repeated here. What is basic is the concept
that endodontid land snails use penial surface features
in species recognition. When sympatric populations
show dimorphic penial surfaces, I conclude that they
are distinct species. In all such cases discovered so far,
the differences in penial structure correlate with
conchological differences. The differences may be large
and obvious, as between Taipidon centadentata (fig.
144) and T. semimarsupialis (fig. 143e-f) or Plan-
udonta concava (fig. 149a-b) and P. intermedia (fig.
149c-d); or the differences in shell features can be
relatively small, as in Taipidon fragila and T.
16
SOLEM: ENDODONTOID LAND SNAILS
uaridentata (fig. 145). Although the size of the
morphologic gap in shell features varies, these differ-
ences correlate with the penial gap and make it
possible to sort the station material into two species.
The penial differences indicate recognition of genetic
incompatibility by the snails. The conchological differ-
ences are expressions of underlying genetic shifts that
led up to the point of genetic incompatibility.
Anatomical study of sympatric material thus
made it possible to recognize which snails consider
each other different species. Analysis of shell variation
provided greater to lesser correlated shell changes by
which the species could be identified.
When populations are allopatric because of a
distinct water gap between islands or from living at
opposite ends of a large island, there will have been no
selective pressure for "species recognition" characters
to evolve. If these isolated taxa have not been
sympatric with congeners or closely related genera,
then selection probably would be toward a stabilized
penial surface. Any deviation from a "normal" pattern
would be at a selective disadvantage, and would tend
to have less reproductive success. In all probability the
extremely conservative pattern of penial structure in
the family relates to just this situation.
At the same time, the populations will have been
subject to varying selective pressures in their different
habitats. Genetic change in other systems having
adaptive value to local conditions will be selected. In
keeping with the general pleiotropic nature of muta-
tions, such changes can be expected to be expressed in
shell feature shifts, even if the particular selective
advantage of the change does not involve the shell
directly. If these allotropic populations with different
genetic systems but virtually identical penial surfaces
became sympatric, either the genotypes would mix (if
genetic compatibility existed) or rapid selection for
species recognition characters would occur (if cross-
population matings produced reproductively sterile or
no offspring). It is obviously impossible to test the
breeding potential of the many allopatric populations
with similar penial types. In judging their reproductive
potential it is necessary to make predictions on the
basis of observations concerning sympatric popu-
lations.
The extent of conchological variation within
populations can be measured and the minimum degree
of conchological difference between sympatric species
determined. In the vast majority of cases the degree of
difference will exceed such minimums. There is no
reason to assume that the currently observed min-
imum represents the actual minimum necessary for
genetic incompatibility to exist. Nevertheless, this is
the best available starting point for evaluating the
significance of observed differences between popu-
lations. It is based on the premise that genetic
divergence will be reflected by phenotypic alterations
in the shell. When the genetic systems have diverged
to the point of reproductively significant in-
compatibility, then, if sympatry occurs, selection for
species recognition characters on the functioning
surfaces of the penis will take place.
After the minimum conchological difference for a
sympatric pair of species in the family is determined,
the relationship of allopatric populations is judged
against this standard. If the degree of difference is less
than the standard, either clinal variation or subspecific
differentiation is proposed. If the degree of difference is
equal to or exceeds the standard, then the populations
are assigned to different species regardless of the
similarity in "species recognition characters."
A precise definition of "minimum conchological
difference" is difficult because shells can vary in many
ways and different taxa show different sets of
variations. Probably Taipidon fragila and T. vari-
dentata show the least substantial changes of any
absolutely or near sympatric species pair where it was
possible to dissect both species. The former (fig. 145)
has a flatter spire, narrower umbilicus, finer ribbing
with fewer microradials between, and a greatly
reduced number of apertural barriers. These are
uncorrelated characters in this situation, since
flattening the spire normally will widen the umbilicus,
while finer and more widely spaced ribbing will have
more microradials between each pair of major ribs.
Taken singly, each of these characters can be shown to
vary within a species unit as widely as they do
between the two Taipidon. Ruatara oparica from
Rapa has the nominate race (fig. 113c-d) with
prominent apertural barriers, a subspecies R. o.
reductidenta (fig. 114e) with greatly reduced barriers,
and a third geographic race, R. o. normalis (fig.
114a, c, d), with an intermediate condition. Races of
Opanara areaensis from Rapa (fig. 104) differ in spire
protrusion or ribbing and umbilical size, but retain
anatomical features in common. It is the combination
of uncorrelated shell and penial differences between
the two Taipidon that is significant. I am reluctant to
establish a minimum number of uncorrelated differ-
ences to be used as a fixed criterion for species
separation. Instead I have given conscious weight to
the apparent "key character usefulness" of a character
within the context of that section of the family in
making particular decisions.
Again using Rapan taxa as examples, it is
instructive to examine two other situations where
judgment had to be made concerning the status of
allopatric populations. Two pairs of taxa in Opanara
that consist of essentially single relict populations (fig.
100) show virtually equivalent shell differences. Table
VI summarizes morphometric data. The differences
between the races of Opanara megomphala (Fig. 106a-
d) stem primarily from a single change in spire
elevation that affected the H/D ratio and D/U ratio,
but had little effect on the diameter and ribbing.
Because there was no noticeable difference in the
METHODS OF ANALYSIS
17
TABLE VI. - SIZE AND SHAPE VARIATION IN RELICT,
ALLOPATRIC RAPAN OPANARA
0. m. megomphala 0. m. tepiahuensis 0. caliculata
Diameter
H/D ratio
Whorls
D/U ratio
Ribs on
body whorl
3.21(2.83-3.52)
0.511(0.1*86-0.561*:
5 l/U-6 1/8
2.22(2.15-2.35)
73.7(71-76)
0_. altiapica
3.36(2.98-3.77) 3.27(3.09-3.39) 2.82(2.63-3.03)
0.1*31+(0. 353-0. 1*81) 0.617(0.595-0.660) 0. 719(0. 66»*-0. 761:
5 1/2-6 1/8 1* 5/8-5 1/1* 1+ 7/8-5 5/8
1.95(1.72-2.08) l+.7l*(l*.09-5.22) 1*. 69(3. 91-5. 53)
6l*.6(5l*-8l)
120.3(117-125:
80.0(61*-9l)
genitalia and the statistically significant differences
were the result of a single alteration, the populations
are called subspecies. Opanara altiapica and O.
caliculata differ in rib spacing (fig. 105a, c), coiling of
the last whorls, size, and penis structure. They are
called different species because there were several
uncorrelated shell characters in addition to the penis
"key," although the degree of statistical difference in
respect to measured variables is no greater than
between the races of O. megomphala.
While each marginal case has to be decided on its
own merits, where three or more substantial, non-
correlated conchological differences exist between
allopatric populations, and these changes are not
known to differ significantly within populations in
that section of the family or genus, then allopatric
populations have been ranked as distinct species. If
fewer than three such changes are present and there is
no indication of "species recognition" differences in the
terminal genitalia, then normally less than specific
level differentiation is proposed.
Subspecies have been recognized in two situations:
where there are one or two uncorrelated characters
that shift with at most slight overlap between
populations on different islands or where there are
dramatic "step dine" patterns of change involving
adjacent areas of the same island. The few subspecies
delineated in this study are true "incipient species."
Further work might demonstrate that they have
reached the level of being distinct. Except for the
populations of Orangia cookei, Opanara areaensis,
and Ruatara oparica on Rapa, natural test of
sympatric or near sympatric populations occurrence
does not exist. The decision on species level versus
subspecies level designation has been, of necessity,
subjective. For the Rapan taxa, the populations are
nearly sympatric and the absence of "character
recognition" features has led to the subspecies-level
designation. As indicated in Table VI, the degree of
measurable difference may be just as large between
some of the subspecies as it is between certain sets of
species. For this reason, species and subspecies have
been given equal status in analyzing patterns of
species level variation.
NATURE OF COMPARATIVE REMARKS
If comparisons are being made between the species
living on a single island or at a single station, where
either there are character displacement phenomena in
respect to closely related species, or the species come
from a variety of phyletic lines, then both quantitative
and qualitative distinctions usually are obvious. Most
users of this monograph will be attempting to identify
species from a particular island, and hence for ease
both in construction and user convenience, most keys
are based on geographic units. A meaningful and
usable comprehensive key to generic units would
require extensive use of anatomical features observable
only by dissection, since conchological variation is
sufficiently large to require multiple entries and a
highly artificial arrangement. Within genera, keys are
based on the known species and represent artificial
identification aids, not an attempt to depict phyloge-
ny. Again, to be of maximum usefulness to the reader,
they are based on conchological data.
When comparing generic-level taxa, it has been
possible, in most situations, to use easily observable
and sharply distinct features. To some extent such
remarks are based on departures from idealized basic
morphotype for the family. The various genera are
viewed as progressive departures from a basic pattern
represented among extant taxa by Minidonta and
Cookeconcha. Such patterns of change have been
somewhat repetitive, as recognized by the Mau-
todontha, Nesodiscus, and Libera levels of special-
ization. Hence generic comparisons are a combination
of direct character differences and patterns of depar-
ture from the more primitive conditions seen in less
specialized, potentially ancestral genera.
Within genera, the non-sympatric species may
differ by combinations of characters that are hard to
define precisely and that are not reflected by averages
of the relatively crude shell measurements. Hence it
18 SOLEM: ENDODONTOID LAND SNAILS
was decided, before writing the definitive descriptions, where a homeostatic genetic system has been bent in
diagnoses, and comparative remarks, to determine the several directions under diverse environmental pres-
average pattern within that genus, or in the case of sures, is implicit in most systematic literature, but
genera with one to three species, to use the presumed frequently has not been articulated or rigorously
ancestral group average as the standard of comparison. applied in analysis. This procedure tends to magnify
As species depart from the average pattern, these the size of differences between species, but is a
differences are commented on in the diagnoses and necessary facet of communication,
remarks. This view of a genus as a monophyletic unit,
PATTERNS OF MORPHOLOGICAL VARIATION
Initial investigations were carried out using gross
methods to study shell and details of anatomic
features observable at 100 X magnification or less with
a dissecting microscope. Slide mounts of unstained
radulae and jaws were examined using a Leitz
Ortholux compound microscope under bright-field,
dark-field, and phase-contrast illuminations. At a later
period it was possible to make some scanning electron
microscope observations of shell structure and sculp-
ture (pp. 30-41), apertural barriers (Solem, 1973b), and
radular denticles (Solem, 1972a, 1973a). Histological
and cytological investigations of anatomical structures
were not attempted. The Bishop Museum anatomical
material had been preserved according to the method
of Cooke (Cooke and Kondo, 1960, p. 4). This involved
drowning the snails for 12 hr, followed by storage in 50
per cent alcohol until they could be sorted in the
laboratory — perhaps weeks or months later. After
sorting the material into species and age classes, the
soft parts were extracted by a water jet or tweezers
(see Kondo and Clench, 1952, pp. 27-28 for a
description of the process). The soft parts often broke
and only terminal portions of the genitalia were
available for study in many species. After a short
immersion in 95 per cent alcohol, permanent pre-
servation of the soft parts was in 75 per cent ethyl
alcohol. While this procedure often yields material
that is quite satisfactory for dissection and gross study,
specimens preserved in this way are not suitable for
histological investigations. Sometimes there was dis-
tinct tissue degeneration in the post-pallial systems, so
that apical genitalia could not be studied.
The following discussion surveys the extent and
frequency of occurrence for patterns of variation found
in various shell and anatomical features as observed
under the limitations outlined above. Where necessary
to understand the significance of certain features,
contrasts are made with the same structures found in
the Charopidae, but a detailed family-level comparison
of shell structure is withheld until Part II. Some data
on family level differences have been presented
previously (Solem, 1973b). Statements concerning the
direction of character change are presented below
without direct justification. The rationale for deter-
mining primitive and derived in relation to the
Endodontidae is covered in the section on phylogeny
and classification (pp. 102-116). Classification has been
based on anatomical rather than conchological criteria,
but the shell is the most usable guide to species
identification. In view of the virtual extinction of the
family, the shell is the only system that will be
available for future study. Hence patterns of
conchological variation are reviewed first, and phyloge-
netic trends are discussed later.
SIZE AND SHAPE VARIATIONS
The following statistical calculations and most
charts omit data concerning the Lau Archipelago
species, Priceconcha tuvuthaensis and Thaumatodon
spirrhymatum, described by Solem (1973d). Their
inclusion would not have materially altered the
results, but would have required repeating a great deal
of work and revising figures for little purpose.
For each species and formally delineated sub-
species, means and ranges of the basic measured
parameters were calculated and then, together with
other variational data, coded and key punched onto
IBM cards for analysis. While these data indicate a
few general patterns of change and permit some
statements concerning the effect that various struc-
tural alterations have on gross measurements, these
averaged data must be used with caution. The extent
of variation within members of a population in regard
to shell shape and form is far greater than would be
suggested by the computer-simulated shells of Raup
(1962) or the studies on Poecilozonites and Cerion by
Stephen J. Gould (1969, 1971). Particularly in regard
to variations in ratios reflecting umbilical size and
shell form, individual specimens of endodontoid species
show little close linkage of variables. The endodontids
have a messy, highly varied, and frequently individ-
ualistic "generating curve" that frequently changes
drastically and perversely during ontogeny. A prime
example of this is the formation of a "brood chamber"
or "brood pouch" from the shell umbilicus by
secondary inward growth of the umbilical lip over a
short segment of a whorl to more than a full whorl of
shell growth (pp. 27-30). In Anceyodonta (figs. 81c, 82f)
there are the rapidly changing umbilical contours.
Major spire protrusion alterations can be seen within
populations of one species, Nesodiscus taneae (fig.
152), and between subspecies of Opanara areanensis
(fig. 104a, c, e). Zonitoids, in contrast, are far more
regular in growth form.
While minimum, mean, and maximum adult
dimensions were recorded for each taxon, graphing of
the minimums, selection of which involved judgment
19
20
SOLEM: ENDODONTOID LAND SNAILS
mean freight
maximum heigtil
FIG. 6. Frequency distributions of mean and maximum shell
height in the Endodontidae.
greater whorl count. Most endodontids lay their eggs
in the shell umbilicus, but on Rapa and Mangareva
Islands there was a tendency for closure of the
umbilicus. Figure 10 charts, on a log scale, the mean
Diameter/Umbilicus ratio for all taxa. Figure 11
separates the Mangarevan and Rapan taxa for
comparison with the overall pattern. Except for the
two subspecies of the Palau Island Aaadonta fuscozo-
nata (Beddome) (fig. 206), barely perforate or closed
umbilici are limited to species from Rapa and
Mangareva. For those species in which the number of
ribs on the body whorl can be counted, the frequency
distribution of rib counts is relatively symmetrical (fig.
12), although the pattern of rib spacing is more
strongly skewed (fig. 13).
= 20
minimum H/D 'atio ---
mean HID ratio —
maximum HID ralio — •
2 93 343 405 481 5 63 6.61 781 941 11D! 12 50
:75 325 375 425 4(5 S25 '« 62S 675 '25 775 825 875 925
H/D ratio
FIG. 8. Frequency distributions of minimum, mean, and
maximum H/D ratios in the Endodontidae.
FIG. 7. Frequency distributions of mean and maximum shell
diameter in the Endodontidae. Diameter intervals are arithmetically
equal segments from a logarithmic scale.
decisions, is not presented for basic parameters
although it is for most ratios. The pattern of shell
height (fig. 6) is positively skewed in distribution,
resulting from the evolution of species with a
secondary brood chamber. As the shell continues to
grow and narrow the chamber opening, height increas-
es at a far greater rate than do other parameters. The
growth vector alters to increase the height, whereas
the diameter of these species is but little affected or
even remains stationary. The diameter plot (fig. 7) is
on a log basis and is symmetrical. As would be
expected, the Height/ Diameter ratio is slightly skewed,
(fig. 8) reflecting the height asymmetry. Whorl count
(fig. 9) correlates well with the height pattern (fig. 6),
again reflecting the number of species with a "brood
chamber," since the increased height results from a
man i mum — . — . —
\
'-I
375 425 475 525 U5 625 675 725 IT) 825 875 925
whorls
FIG. 9. Frequency distributions of mean and maximum whorl
counts in the Endodontidae.
PATTERNS OF MORPHOLOGICAL VARIATION
21
45
40
35
30
20
10
minimum D/U
mean D/U
maximum D/U —• — .——
I I I
1.50
1.86
2.31
3.56 4.42
5.49 6.76
D/U ratio
8.41
10.51 13.01 16.41
20.31 30.00 boapeerly closed
FIG. 10. Frequency distributions of minimum, mean and maximum D/U ratios in the Endodontidae. D/U ratio intervals are arithmetically
equal segments of a logarithmic scale.
Each of the above basic measurements results
from the interaction of several variables. Factor
analysis would permit assigning weight to individual
elements, but this would require far more elaborate
and accurate measurements prepared from shell cross-
sections than seemed worthwhile for this systematic
review, plus computer competence and access that
were not available to me. As examples of the changes,
discussion is presented here concerning the effects of
two more obvious changes, body whorl contour and
spire protrusion, in relation to the basic measurements.
Then a brief review on the pattern of change in
umbilical contours precedes consideration of brood
chamber formation and its effects on shell size and
shape. A short concluding section on whorl count
correlated variation provides background data for
subsequent phylogenetic analysis.
Body whorl contour
While no quantitative measurement of body whorl
contour was possible, visual coding into five categories
was relatively unambiguous. The actual coding of the
states was done from specimens, the written diagnoses,
and illustrations, with difficult judgment decisions
necessary in only a few cases. The approximate
contour states are indicated in Figure 14A-E. These
are termed: A) laterally compressed; B) evenly
rounded; C) flattened slightly above and below a
22
SOLEM: ENDODONTOID LAND SNAILS
45 f—
I I I
1.75 3.00
4.00
5.00 8.00 1725
D/U ratio
brood
pooch
FIG. 11. Pattern of umbilical size in Rapa and Mangareva Island
Endodontidae compared with the frequency distribution for the
entire family.
rounded periphery; D) flattened above and below an
angled periphery; and E) distinctly keeled. A sixth
category, F, contains all species in which a brood
chamber has been developed. The latter change
overrides the alterations in whorl contour. Treatment
of these taxa separately is essential.
In the four charts, the x axis digits refer to the
number of taxa in that grouping, while the y axis
figures give the measurement range for the particular
parameter. There is no correlation between D/U
ratio (lower right of fig. 14) and body whorl contour
variation, and virtually no change in shell height
(upper left) until a protruded keel is developed. The
development of a peripheral keel reduces the options
for attachment of succeeding whorls. To fasten the
parietal-palatal margin above such a keel leaves the
parietal wall with a strong projection into the very
area of the apertural cross-section where the
comparatively bulky heart and kidney lie and through
which (at the apertural opening) the head with its
bulbous buccal mass must be withdrawn. Such a
procedure would be highly inefficient. I know of no
snail in which the attachment lies well above a
protruded keel. The peripheral keel itself, or even
slightly below it, marks the attachment point for
subsequent shell growth. The slight height increase
shown by keeled species probably reflects a negative
feature, in that once the keel is started, reduction in
S, 20
minimum ribs •
mean ribs
maximum ribs •
70 90 110
ribs on body *tK>rl
130 150
170
190 200'
FlG. 12. Frequency distributions of minimum, mean, and
maximum rib counts on the body whorl in the Endodontidae. Species
with reduced or irregular ribbing omitted.
shell height becomes mechanically far more difficult to
accomplish. Brood chamber species (state F) are
included to emphasize their increased shell height.
Shell diameter (upper right of fig. 14) increases
steadily with the change in whorl contour, except for
going from state C to D. Since the only alteration in
this transition involves the upper and lower lateral
margins of the body whorl, the periphery-to-periphery
distance would remain unchanged. In state E the
401-
135 7 9 11 13 15 17 19'
ribs per mm.
FIG. 13. Pattern of rib spacing on the body whorl in terms of
ribs/mm, of peripheral circumference. Species with partly reduced or
irregular ribbing omitted.
PATTERNS OF MORPHOLOGICAL VARIATION
23
median —
x —
height
E
E
38
43
28 29
diameter
38
43
21
14
28
29
H/D ratio
D/U ratio
060 r—
055
050
38
43
28
29
6r-
37
37 19
n
13
27
FlG. 14. Effects of changes in peripheral whorl contour on some basic measurements in the Endodontidae. See text for explanation of
character states A-F, "n" refers to the number of species level taxa having each state. The D/U ratio graph omits species with closed or barely
perforate umbilici.
actual lateral protrusion of the periphery on each side
would, and does, drastically increase the diameter. The
proportionate increase in diameter from states E to F
is less than the change in height (upper left). Again
this reflects the mechanics of brood-chamber forma-
tion.
Correlated with the increase in shell diameter,
which results from further lateral expansions of the
body whorl, is a gradual decrease in the H/D ratio
(lower left). The slight mean levelling in the H/D ratio
of state E and rise in height for group E results from
the Palau Island Aaadonta being mostly in this group.
This genus has by far the most elevated spire and
greatest number of species with keeled peripheries for
any genus in the family.
Data on whorl count correlations are presented in
Table VII. The difference from state C to D is not
significant ("t" = 1.3373 with 33 df), but the change
from C to E is significant ("t" = 2.6954 with 47 df), It
may be that the increase in shell diameter combined
with keeling is a mechanism that serves to decrease
shell-height increment as the whorl count is raised. A
retardation of the increase in shell height would keep
open narrower niches for the snail to retreat into. The
keel protrusion would adjust cross-sectional whorl area
to compensate for the lessened height increment.
In summary, changes in the whorl contour
directly affect the shell diameter and H/D ratio, but
have no correlation with D/U ratio and only slight
direct effects on shell height. Whorl-count increase
correlates slightly with keel formation, but otherwise
there are no major identifiable results from whorl
contour changes.
24
SOLEM: ENDODONTOID LAND SNAILS
TABLE VII. - WHORL CONTOUR AND WHORL
COUNT CORRELATIONS
Character
state
A
B
C
D
E
F
X and SEM
whorl count
5.
5.35±0.11
5.35±0.12
5.66+0.21
5.8?±0.lH
6.78+0.11
Number of
taxa
38
21
1U
28
29
Spire protrusion
If the whorls of a typical shell could be unwound
and then coiled in different fashions, certain changes
would be obvious. If the rate of whorl descension was
great, resulting in a protruded spire, and the whorl
count remained the same, the shell height would be
larger, the diameter less, the H/D ratio would
approach nearer to unity (or even above), the
umbilicus would be narrower, and the D/U ratio larger
in number. If the spire was flattened or depressed
resulting in little or no whorl descension, the height
would be less, the diameter greater, the H/D ratio a
lesser proportion of unity, the umbilicus wider and the
D/U ratio lower in number.
Isolating spire protrusion for analysis is difficult,
since the degree of body-whorl deflection during adult
growth varies greatly between taxa. This parameter
has great influence on shell height and some influence
on shell diameter. To use the ratio of spire protrusion
above the body whorl to total shell height would add
the variable of body whorl descension. I have chosen to
indicate the degree of body whorl protrusion through
use of an index obtained by dividing the actual spire
height above the body whorl (E-F in fig. 5) by the
body whorl width (F-G in fig. 5) taken at a point
directly below the spire. Adjustments in the latter
measurement to allow for the changes resulting from
keel protrusion would slightly refine the data, but
were not feasible or thought necessary at this level of
analysis. Measurements were made on type specimens
only, with the exceptions noted below.
The resulting data were clumped into five states,
which are characterized as: A) spire flat or depressed;
B) index 0.01-0.250; C) index 0.251-0.500; D) index
0.501-0.750; and E) index 0.751 to the observed
maximum of 1.33 in Gambiodonta grandis. About 10
per cent of the species were sufficiently near the group
dividing points that several specimens were measured
and the means used to decide group placement.
Individual variation within large populations was far
less than found in the Charopidae, although the total
range frequently overlapped two states. The vast
majority of taxa could be assigned to a group without
question. A rough indication of the divergent appear-
ance is given by the small diagrams at the top of
Figure 15. Both mean and median parameters are
given in the diagrams.
The major effect of spire elevation is on H/D
(lower left) and D/U (lower right) ratios. As the spire
is protruded, the H/D ratio increases and the
umbilicus becomes narrower. Two minor shifts in the
charts require explanation. The lack of H/D ratio
change between C and D probably reflects the fact
these ratios are the typical pattern for the family (fig.
TABLE VIII. - SPIRE PROTRUSION AND WHORL COUNT CORRELATION
Character
state
A
B
C
D
E
Brood chamber absent
Brood chamber present
Whorl count
X and SEM
5.21+0.19
5.2^+0.12
5.52±o.09
6. 03*0. 12
6.o8±o.i6
Number of
taxa
IT
59
21
5
7.63
6.98
6. hO
6.93
Number of
taxa
0
1
h
10
PATTERNS OF MORPHOLOGICAL VARIATION
25
median
x
height
diameter
3.90r-
3.15
Z40
1.65
17 44 63 31
n
6.50 r-
5.50
4.50
350
19
17
44 63
n
31
19
H/D ratio
0.650
0.600
0.550
0.500
0450-
9.00
7.50-
600 —
450-
3.00
D/U ratio
without brood pouch
17
44 63
n
31
19
17
41 63
n
19
FIG. 15. Effects of changes in spire protrusion on basic measurements in the Endodontidae. See text for explanation of character states A-E,
"n" refers to the number of species level taxa having each state.
8). Either a more or less protruded spire represents a
departure from the norm and hence may drastically
alter the H/D ratio. In the D/U ratio chart, the dip in
the group E median results from inclusion of the very
widely umbilicated Nesodiscus in this category.
Changes in shell height (upper left) follow the
common sense evaluation of the data, as essentially do
the changes in shell diameter (upper right). If the spire
is pushed down and into the middle of the coiling
plane, then in order to preserve the same total whorl
volume, diameter would have to increase; thus the
greater diameter for the group A taxa. Flat or
depressed spires apparently are advanced characters in
the Endodontidae, thus part of the diameter increase
probably is phylogenetically determined. The greatly
increased diameter in groups C, D, and E reflects two
factors— an increasing percentage of taxa with brood
26
SOLEM: ENDODONTOID LAND SNAILS
chambers developed and an increase in whorl count.
This is documented in Table VIII, which shows that
the development of a brood chamber correlates with a
moderately high spire, but there is no correlation
among brood pouch species between spire protrusion
and whorl count.
Umbilical contour
Umbilical openings are used by endodontids as an
egg deposition site. The variations in umbilical contour
and basic shape are far greater than in mollusks where
this opening is a byproduct of growth and lacks other
functional significance. In discussing the taxa, the
umbilicus was described as showing one of 11 shapes
and contours. These were subsequently coded as
States:
1. V-shaped, regularly decoiling (40 taxa)
2. V-shaped, last whorl decoiling slightly more
rapidly (3 taxa)
3. V-shaped, last whorl decoiling much more
rapidly (2 taxa)
4. U-shaped, regularly decoiling (23 taxa)
5. U-shaped, last whorl decoiling more rapidly
(22 taxa)
6. cup-shaped (18 taxa)
7. U-shaped, barely decoiling (17 taxa)
8. secondarily narrowed to form a "brood cham-
ber" (29 taxa)
9. barely perforate (10 taxa)
10. closed by contraction (3 taxa)
11. closed by reflection of the columellar lip (7
taxa).
Rough cross-sectional views and an indication of the
multiple directions in character change are shown in
Figure 16. The difference between V and U shaping is
a factor of early ontogeny. In those with a V-shaped
umbilicus, the initial umbilical width is narrower.
During subsequent growth the point of attachment for
the columella on the basal margin of the preceding
whorl remains the same. The shape of the opening is a
simple V. A good example of this is seen in Minidonta
hendersoni (fig. 63d). In those with a U-shaped
umbilicus, the initial umbilical width is proportionate-
ly wider and the point of attachment for the columella
on the preceding whorl is much nearer the basal-
umbilical margin. The same point of attachment is
maintained through subsequent growth. The basic
shape thus becomes a U with only slight to moderate
divergence of the sides as in Endodonta ekahanuiensis
(fig. 166c). The difference in appearance is caused by
both a different initial width of the umbilicus at the
apex and changed attachment point for the succeeding
whorls. There is no strict taxonomic linkage, since the
two types of umbilici occur in equal numbers of
Thaumatodon and Mautodontha, but Cookeconcha,
Taipidon, and Australdonta have mostly V-shaped
umbilici, while Opanara and Endodonta show mostly
U-shaped variants.
Table IX summarizes the size and shape correla-
tions with umbilical contour shifts. The difference in
whorl count between States 1 and 4 is significant ("f
= 2.9974 with 61 df), but the other changes are not
statistically meaningful. Taxa with U-shaped umbilici,
States 4, 5, and 7, do show differences from each other.
Those in which the umbilicus is regularly decoiling
(State 4) have an obviously wider umbilicus and
significantly lower H/D ratio ("t" = 2.0833 with 38 df)
than those with a barely decoiling umbilical opening
(State 7). Those in which the last whorl decoils more
rapidly (State 5) average smaller in diameter than the
others, but the range in size is so great that the
difference is not significant ("t" = 0.7851 with 37 df).
Unfortunately, there is virtually no data available
concerning egg size in the Endodontidae, so that the
significance of the essentially identical D/U ratio for
States 5 and 7 is uncertain. It may be coincidental.
Umbilici that are cup-shaped (State 6) occur primarily
in taxa at the Nesodiscus level of specialization. These
taxa have a statistically significantly higher whorl
count than State 7 ("t" = 2.2095 with 32 df), an
TABLE IX. - SIZE AND SHAPE CORRELATIONS WITH UMBILICAL CONTOUR CHANGES
Umbilical
shape
State 1
State 1*
State 7
State 5
State 6
Mean and SEM
Height Diameter H/D ratio D/U ratio Whorls
3.80+0.15 5.08±0.09
3.8U+0.17 5.57±0.15
5.79+.O.U1 5.6l±0.15
Uo
1.85±0.ll»
3.78±0.2U
O.U89±0.010
23
1.96±0.17
3.95±0.38
0.507±0.013
17
2.0lj±0.12
3.72+0.25
0. 562+0. 02k
22
1.78+0.19
3.32+0.39
0.550+0.017
18
2.08±0.18
i+.8U±0.27
0.1+29±0.012
2.17±0.09
6.15±0.19
PATTERNS OF MORPHOLOGICAL VARIATION
27
§ Brood Pouch li
••r:''i;:-"l 3:
fl
lip reflection
constriction
constriction
lip reflection
FIG. 16. Patterns of phyletic change in umbilical shape and size.
obviously wider umbilicus, lower H/D ratio, and are
larger in size.
Table X shows the relative lack of strong
correlations between degree of spire protrusion and
umbilical contour, except for taxa with either a brood
chamber (State 8) or barely perforate umbilici. Spire
protrusion is symmetrically distributed in frequency
(see Totals column of table X). There are some skewed
correlations in contour. V-shaped umbilici are restrict-
ed to forms with relatively low spires. This corresponds
to the doming effect mentioned by Gould (1969, p.
432). The shift in frequency shown by States 4 and 5
may be partly caused by the same phenomenon, as is
the restriction of perforate umbilici (State 9) to those
taxa with elevated spires. In contrast, closed umbilici,
those barely decoiling, cup-shaped umbilici, and those
with the last whorl decoiling more rapidly do not
correlate with spire protrusion.
Inspection of Figure 16 shows that from the
generalized conditions, specialized states can be
achieved in several different ways. In the systematic
discussions under particular genera, the patterns of
such change are reviewed individually. Such data is
based on gross examination. A more elegant analysis
would have been possible by using cross-sectional
profiles, but the time needed for such preparations was
not available. One aspect that greatly influences
umbilical volume is the interior wall contour.
Frequently the sides of the umbilicus are flattened. No
accurate measurement of this was practical and,
although mentioned throughout the systematic sec-
tion, no general analysis is presented.
The above sketchy data on umbilical shape and
contour is necessary as an introduction to the major
conchological change seen in the family, formation of a
brood chamber. It also serves to suggest some of the
complexities concerning the umbilicus in the Endodon-
tidae, nearly all of which relate back to its functional
use for egg deposition.
Brood-chamber formation
Shell growth that secondarily narrows a widely
open umbilicus to form a brood chamber has occurred
at least five different times in the Endodontidae.
Three genera, Pseudolibera, Libera, and Gambia-
28
SOLEM: ENDODONTOID LAND SNAILS
TABLE X. - UMBILICAL CONTOUR AND SPIRE PROTRUSION
Spire
Elevation
Depressed
or flat
0.01-0.250
0.251-0.500
0.501-0.750
over 0.751
Totals
17
kk
63
33
19
Umbilical States
1-3^56
16
20
13
6
donta, contain nothing but species with brood cham-
bers. In two other genera, single species (Endodonta
marsupialis and Taipidon semimarsupialis) show the
secondary narrowing. Other species of the same genera
have a U-shaped umbilicus that would require only
the secondary narrowing to form a brood chamber. An
additional three species show slight umbilical narrow-
ing during the last whorl of growth and hence form
prototype brood chambers. Kleokyphus callimus (fig.
95c) from Makatea, Tuamotu Islands, Kondoconcha
othnius (fig. 162c) from Rapa, and Thaumatodon
euaensis (fig. 194c) from Eua, Tonga all are relatively
narrowly umbilicated species that have last whorl
constriction of the openings. Thus a total of eight
lineages in the family produced species in which the
umbilical openings have become secondarily narrowed
to form an egg-holding cavity.
The three genera in which all species show
striking umbilical alterations are very similar in size
and shape. The method of chamber formation is
different in the three genera and independent deriva-
tion of the chamber is certain. Pseudolibera from
Makatea (fig. 168) has the narrowing process occur
over VA whorls. After a period of stabilized umbilical
width, there is gradual inward growth of the entire
columellar wall that accelerates for one-half whorl,
then finally stabilizes in the same position relative to
the shell axis for the last one-quarter whorl of growth.
In Gambiodonta (fig. 185) from Mangareva, the
columellar-basal margin first becomes angulated, then
keeled. Following this there is an abrupt one-quarter
to one- third whorl growth toward the middle of the
umbilicus, followed by three-quarters to two-thirds
whorl growth with the columellar-basal margin retain-
ing the same position relative to the geometric center
of the umbilicus. Completing the one whorl of growth
produces a brood chamber with sharply narrowed
opening. In Libera from the Society and Cook Islands,
closure is the result of gradual inward columellar
growth over about two whorls of shell increment. The
only exceptions to this pattern are seen in such
7
13
3
3
3
2
7
1
2
8
5
1
8
10-11
i
U
10
lit
2
5
5
1
depressed species as Libera gregaria and L. recedens
(fig. 175) from Moorea and L. streptaxon (fig. 179)
from Tahiti, where parietal wall detachment beginning
at the last whorl of growth initiates and provides most
of the impetus for umbilical narrowing. In these
species this alteration seems to be a compensatory
adaptation to preserve maximum volume inside the
umbilical chamber. The depressed spires act to reduce
the volume of the chamber, but the shorter closure
period effectively adds to the volume.
Taipidon semimarsupialis (fig. 143e-f) from Nuku-
hiva, Marquesas has an inward curve of the entire
columellar wall during the last 11A whorls of growth
producing the brood chamber. In Endodonta marsu-
pialis (fig. 167b) from Oahu, Hawaii there is an inward
extension of the columellar-basal margin over the last
two whorls of growth. Both of these species show
many anatomical differences from the dissected Li-
bera.
Despite being unable to dissect either Pseudoli-
bera or Gambiodonta, the differences in brood-
chamber formation combine with other conchological
criteria to separate them generically.
Considering just the 29 specific-level taxa in
Pseudolibera, Libera, and Gambiodonta plus Endo-
donta marsupialis and Taipidon semimarsupialis,
no brood pouch
brood pouch
FIG. 17. Mean shell height in species with and without a brood
chamber.
PATTERNS OF MORPHOLOGICAL VARIATION
29
there are marked average differences from non-brood
chamber species. Since the numbers of taxa involved
are quite disparate, the data for Figures 17-20 have
been converted into per cent of taxa for ease in direct
comparison. Shell height (fig. 17) is obviously much
greater in brood-chamber taxa, although a few of the
normal taxa are as high. The nature of these
exceptions involves gigantism (Nesophila tiara), a
combination of large size and increased whorl count
(Nesodiscus magnificus, N. fabrefactus, Kleokyphus
hypsus), or high-spired, proto-brood chamber taxa
(Endodonta kamehameha, E. fricki). Shell diameter
(fig. 18) is less sharply demarcated in brood-chamber
taxa, since the pattern of growth in forming the
chamber involves height more than diameter. Selection
for ability to retreat into narrow niches probably
influenced the diameter and H/D ratio (fig. 19) to a
marked extent. Finally, the increased whorl count (fig.
16 19 23 21 32 36 II 52 61 1! it 102 118
mean diameter
FIG. 18. Mean shell diameter in species with and without a brood
chamber.
20) of brood-chamber taxa probably reflects the fact
that brood-chamber formation is an improvement
upon a functioning system. Endodontids obviously
survive very well by laying eggs inside a "normal"
umbilicus. Formation of the brood chamber permitted
laying a larger number of eggs, increasing the per cent
retained until hatching (particularly if the eggs are
close to the chamber opening in diameter), and
possibly reducing predation upon the eggs. Thus by
continuing growth after reproductive maturity, the
reproductive success rate would be increased. Hence
the larger number of whorls involved in brood
chamber formation might be compensated for by a
reduction in energy directed toward egg production.
Brood chamber narrowing occurs after there is already
a sufficiently large umbilicus to hold eggs. Thus the
average whorl count would be higher in brood-
chamber taxa.
In at least some species the opening to the brood
chamber becomes so constricted that the hatched
young have difficulty exiting. In Libera streptaxon
(fig. 180) specimens normally show eroded margins
where the young apparently have gnawed their way to
the external world. Libera fratercula from the Cook
Islands carries this procedure to the ultimate possi-
bility. During brood chamber narrowing the apical soft
£
i
s
i
20
no brood pouch
brood pouch
325
375 .425 475 .525 .575
mean H/D ratio
625 .675 725 .775
FIG. 19. Mean H/D ratio in species with and without a brood
chamber.
parts withdraw from the early whorls. Instead of
leaving this area vacant or filled with mucus deposits,
as is common in multi-whorled land snails, it is filled
with calcium crystals, effectively turning the shell
apex into a solid rock. The largest specimens will have
soft parts in the last four whorls of growth with as
many as 4% whorls "evacuated" and closed up with
calcium. The young gnaw their way up through the
shell apex in order to exit (Solem, 1969a, p. 11, fig. 3).
Since this species lives in the shore-line coral rubble
tossed up by severe storms, calcium is super-abundant.
The extra calcium needed to fill in the apical whorls is
readily available and retention of the young for a
longer period keeps them in a humid niche for a longer
time.
No data is available concerning the exact size of
the young at time of exit from the brood chamber.
50
40
30
£
Z 20
10
no brood pouch
brood pouch
4.9 5.6
mean whorl count
6.4
7.8
FlG. 20. Mean whorl count in species with and without a brood
chamber.
30
SOLEM: ENDODONTOID LAND SNAILS
TABLE XI. - WHORL COUNT CORRELATED SIZE INCREMENT
Whorl Count
Range Median
3.6-1+.95 ^. 55
5.0-5.5 5.25
5.55-6.0 5.TO
6.05-6.95 6.1+0
7. 05-8. 05 7.30
I'lumber
of taxa
27
58
35
1+0
17
There is considerable variation in size of the young
within the brood chamber, so that growth does occur
after hatching and before exiting.
Effects of whorl increment
Although in the Charopidae there is considerable
and obvious difference in the rate at which the whorl
cross-sections increase in size, species in the Endodon-
tidae have a relatively uniform pattern of change.
Except for obvious cases of gigantism in which the size
of the nuclear whorls is grossly enlarged, such as
Nesodiscus magnificus and Nesophila tiara, size
increase in the Endodontidae correlates with contin-
ued additive growth that results in a higher mean
whorl count. Spire protrusion, body-whorl descension,
keel development, and relative cross-sectional area
influence and modify the results, but basically simple
whorl count increase results in most of the observed
size increment.
Data on this are summarized in Table XI. The
whorl-count intervals are not equal in distance, since
the clustering around the median whorl count of 5Vz +
was so great that a division into two parts seemed
advisable. The relatively small size increment between
the 5.25 and 5.70 medians is an artifact of shortened
interval rather than a change in pattern. Both
diameter and shell height increase regularly and
dramatically as whorl count is increased. There is only
minimal change in proportions correlated with whorl
count, since the alteration in the H/D ratio is
negligible, As has been demonstrated above (pp. 21-27),
there are other factors that have much greater effects
on shell proportions.
SHELL SCULPTURE
Since the 1850's almost any small helicoidal land
snail with numerous radial ridges and/or a reddish-
brown or flammulated color pattern was placed in the
"endodontoid" complex. This was in contrast to the
smooth, shiny-shelled "zonitoid" taxa. Dissections have
split off various paryphantid, pyramidulid (pleurodis-
cid), strobilopsid, polygyrid, and camaenid taxa, but a
core of sculptured litter dwelling taxa remain for
consideration.
X and (% of change from prior group)
Height Diameter H/D ratio
l.U6(-) 2.80(-) 0.1+97(-)
2.11(1*14.5%) 3.67(31.1%) 0.523(U. 7%)
2.3Ml0.9%) 3. 85(1+. 9%) 0.51+1(3.!*%)
3.10(32.5%) l+.8o(2l+.7%) 0.561+(l+.3%)
1+. 1*1(1+2. 3%) 6.88(1+3.3%) 0.556(1.1+%)
Recently I have been able to initiate scanning-
electron-microscope studies not only of sculpture
features on the shell surface, but also investigations of
the mechanics used to bond together the periostracal
and underlying calcareous layers. There appear to be
major differences in bonding mechanisms, whereas
similar external sculpture on the spire and body whorl
has evolved in unrelated lineages. The data on bonding
mechanisms are too fragmentary for presentation at
this time. The Pacific Island endodontoid family taxa
do show clear differences in their relative use of
calcareous versus periostracal sculptural components,
the formation of sculpture on the postnuclear whorls,
and in the pattern of apical sculpture. Discussion of
basic sculptural structure is restricted to these aspects
pending completion of more detailed investigations on
layer bonding and details of surface sculpture in
Australian and New Zealand taxa.
Data is presented below on the nature of micro-
and macrosculptural elements; family-level differ-
ences; additive sculptural features; patterns of vari-
ation in major rib numbers, size and spacing; the
nature of changes correlated with rib spacing and rib
reduction; and a brief hypothesis concerning the
functional significance of shell sculpture in the
endodontoid genera.
Types and growth patterns
Normal shell sculpture in the Endodontidae
consists of major radial ribs plus a complex micro-
sculpture that is barely visible at 80-100 X mag-
nification. The major ribs are visible either to the
naked eye or at less than 30 X magnification. The
microsculpture can be analyzed with the scanning
electron microscope (SEM) at 300-3,000 X mag-
nification. These two elements of sculpture are
additive, with the microsculpture continuing onto and
across the major swellings. This is quite clearly shown
in, for example, Rhysoconcha atanuiensis (the lower
half of fig. 21b). There are four to six microradial
riblets in the "trough" between each pair of major ribs.
After the initial abrupt "rise" of the major ribs, several
crowded microradials are clustered on the upper and
PATTERNS OF MORPHOLOGICAL VARIATION
31
anterior (descending) side of each major rib (left side
in cited figure). The spacing between these micro-
radials obviously is much narrower than between the
riblets in the "trough" area. Inspection of other species
shows similarity in results, but considerable variation.
Gambiodonta agakauitaiana (fig. 22d-e) has riblet
crowding on the posterior (ascending or right) side of
the major ribs. Australdonta raivavaeana (fig. 23a-b),
which has relatively low and inconspicuous major ribs,
shows no consistent pattern of riblet crowding on one
side or the other of the major ribs, although usually
one side is more crowded. Nesodiscus taneae (Garrett)
(fig. 31c-d), where major ribs are greatly reduced,
shows no change in riblet spacing. Several Polynesian
FIG. 21. Sculpture of Rhysoconcha atanuiennis and Thaumato-
don decemplicata (Mousson): a-b, Rhysoconcha atanuiensis. Station
367, Atanui Bay, Rapa. BPBM 140161. a, apex and early postnuclear
sculpture (ca. 300x); b, suture between apex and first postnuclear
whorl, note absence of microspirals on postnuclear (ca. 1,000 X); c,
Thaumatodon decemplicata. Paratype. Nukufetau, Ellice Islands.
FMNH 116990 ex Mousson coll.
Charopidae (Solem, unpublished data) consistently
had riblet crowding on the ascending rib side.
Such spacing variation can be investigated by
growth studies. In the land prosobranch family
Diplommatinidae, A. J. Berry (1962) has shown that
Opisthostoma retrovertens Tomlin usually added one
rib and an interspace during each 24 -hr. period. Such
growth could occur during both day and night periods,
but usually happened overnight. Repair of shell breaks
and drying of the habitat either interrupted growth or
produced finer and more crowded ribs. When the snails
were kept under conditions of high humidity and in
total darkness, rib production increased to more than
one per day.
Obviously, it is not possible to transfer this
observational data to the totally unrelated Endodon-
tidae. Available data does suggest the relative timing
pattern involved in major rib formation, although not
the length of the cycle. With the assumptions that the
microradials are deposited at equal time intervals and
that control of their deposition is partly independent
of horizontal anterior growth, then the spacing pattern
can be modelled quite simply. For example, in
Rhysoconcha there would seem to be a sudden upward
surge of both inter-riblet conchin template and
calcium deposition that results in an underlying major
rib protrusion accompanied by a widening of the area
between adjacent microradials. Following this there is
FIG. 22. Sculpture in Gambiodonta: a-b, Gambio-
donta mirabilis. Station 277, Ganhutu, Mangareva,
Gambier Islands. BPBM 138981; a, apex and early
postnuclear whorl (ca. lOOx); 6, detail of late apical
sculpture (ca. 300x); c-e. Gambiodonta agakaui-
taiana. Station 195, Rikitea, Mangareva. BPBM
138903; c, apical sculpture, note crystallization patterns
in wear areas (ca. 300 x ); d, postnuclear sculpture, note
microreticulation (ca. 100 X ): e, detail of postnuclear rib
endings at periphery (ca. 300 X ).
32
PATTERNS OF MORPHOLOGICAL VARIATION
33
FIG. 23. Postnuclear sculpture of Australdonta raivavaeana. Station 674, Mt. Turivao, Raivavae, Austral Islands. BPBM 147529: a, portion
of last two whorls, note grooved pattern in upper left (ca. 100 X ); b, suture between body and penultimate whorl (ca. 300X ); c, detail of suture,
note changed subsutural riblets (ca. l,000x ); d, suprasutural sculpture (ca. 3,000x).
a marked slowing in horizontal growth that results in
several microradials being formed close together in the
conchin template layer. Gradual return to a normal
rate of horizontal increment and sudden lowering of
the accretion plane to the whorl surface level starts a
new rib interstice. Growth would continue at an even
rate to the next surge point, starting the cycle over
again. Gambiodonta and the Charopidae would appear
to use the opposite tactic, with a slowdown in
horizontal growth and resultant microradial crowding
preceding the major rib peak. Acceleration of the
horizontal growth rate would increase the distance
between the microradials on the outer rib face before
returning to the normal interval pattern. Forms with
reduced ribs could have irregularity in surges produc-
ing the resultant variation in Australdonta. The lack
of change in Nesodiscus probably is a result of low
surface relief.
Figure 24 diagrams the pattern of these activities.
The basic hypothesis that microradial construction
occurs at regular time intervals, while horizontal
growth is in irregular surges requires experimental
testing. This theory does indicate a way in which the
different riblet spacing observed could be achieved.
34
SOLEM: ENDODONTOID LAND SNAILS
JUU
a
I I
%U^mA^^
mill
1 1 1 1 1 1 1 1 1 r 1 1 M 1 1 1 1 1 1 1
FIG. 24. Patterns of radial surface sculpture in selected Endodontidae: a, Rhysoconcha atanuiensis, based on Figure 21b; b, Gambiodonta
agakauitaiana, based on Figure 22d-e, c, Australdonta raivavaeana, based on Figure 23a-b, d, Nesodiscus taneae (Garrett), based on Figure 31c-
d. Upper diagram indicates cross-sectional view of shell differentiating conchin (outer) and intial calcium (inner) layers; lower diagram plots
horizontal distance between radial riblets. All figures greatly enlarged, but not to same scale
The outermost periostracal layer of conchin, a
sclerotized protein layer, acts as template for the
initial calcium layer. Whether this periostracum is
present or splintered off in dried individuals, the apical
microsculpture appears the same at 100 X mag-
nification. Even at 3,000 X magnification (for example,
Minidonta hendersoni, fig. 25d) bits of flaking peri-
ostracum are seen to conform exactly to the under-
lying calcium layer. This is not correct in regard to the
postnuclear sculpture, where both riblets and ribs may
have high, lamellate periostracal extensions. In a very
few species, notably Cookeconcha hystrix (Pfeiffer) and
C. decussatulus (Pease) (fig. 26a-c), the periostracum
has elongated "hairs" or "setae" produced. In Rhyso-
concha atanuiensis (fig. 21b) and Australdonta raiva-
vaeana (fig. 23a) the partly lamellar extensions and
underlying calcuim layers of particular ribs are
obvious.
This means that while the major sculpture visible
to the naked eye is composed mainly of calcium
swellings, the microsculpture consists of a primary
FIG. 25. Sculpture of Minidonta hendersoni. Station 254,
Henderson Island. BPBM 149858: a, apical and early postnuclear
whorls (ca. 300X ); b, postnuclear sculpture, note fine microspirals; c,
apical sculpture, note wavy microspirals (ca. l.OOOx); d-e, details of
apical sculpture (ca. 3,000 X ).
35
36
SOLEM: ENDODONTOID LAND SNAILS
conchin layer underlaid, except for the periostracal
fringes, by a duplicate layer of calcium. The fringes
usually are extremely narrow. Probably the height of
the underlying calcium riblet is a practical compromise
between the need for a second line of surface
irregularity in case of conchin layer loss and the
desirability of keeping the vertical extensions narrow
for as great a distance as possible, to retain a narrow
edge when partial breakage occurs.
Family-level differences
Apical sculpture in the Endodontidae consists
primitively of fine radial riblets and large single radial
ridges combined with a very fine microspiral sculpture
of "squiggly" cords. The latter look as if someone with
a hangover had attempted, unsuccessfully, to squeeze
a straight line of toothpaste from a tube. These
microspirals are crowded, very narrow and seemingly
independent of the radial sculpture. Typical in
appearance is the apical sculpture of Mautodontha
aoraiensis (fig. 27b). Even if the major radial elements
are lost by mutation, as in Aaadonta (figs. 28, 29), the
microspirals on the apex (fig. 29a) are diagnostic. In a
few Hawaiian taxa belonging to Cookeconcha (fig. 30)
both macro- and microsculpture are reduced on the
apex, while complex postnuclear sculpture is retained.
In the Lau Archipelago Priceconcha (Solem, 1973d)
only remnants of microsculpture remain on the last
two whorls. On early postnuclear whorls the micro-
spiral sculpture usually is clearly visible, but on late
postnuclear whorls secondary alterations in rib spacing
or sculpture reduction frequently obscure this charac-
teristic feature.
In contrast, the Pacific Island Charopidae have an
apical sculpture primitively featuring broadly rounded
spiral cords, usually 8 to 12 in number, without any
radial elements. Frequently just before the termina-
tion of apical growth, one to three low radial
undulations will appear in the shell surface. In a few
species, the number of spiral cords has been increased
to more than 20. and there are 10-20 radial undula-
tions on the apical shell surface. Under optical
examination, this mimics the appearance of the
endodontid apex, but SEM examination shows that
the spirals are simple cords and that the radials are
surface undulations rather than ribs. Postnuclear
sculpture in the Charopidae appears abruptly in a
small fraction of a millimeter. Optically it resembles
the Endodontidae very closely in having major and
minor radials, plus secondary spiral microsculpture.
The latter differ in that the microspirals are not
FIG. 26. Postapical sculpture of Cookeconcha decussatulus
(Pease). West Maui, Hawaiian Islands. FMNH 46605: a, section of
body whorl at 300 x showing periostracum flaking from major ribs
and difference in shape of periostracal extensions and underlying
calcium ridge; b, early postnuclear sculpture at 300 x showing
secondary spiral cording, periostracal hairs and flaking periostracum;
c, setal area in b at 1,000 x, flaking periostracum at upper right
twisted 90° to left and out of normal position. Arrows on a and b
point to microspiral riblets in calcium layer of shell.
PATTERNS OF MORPHOLOGICAL VARIATION
37
"squiggly," form buttresses to the microradials (for
example, Ptychodon microundulata, see Solem, 1970b,
pi. 59, figs. 9-11), and thus are much higher next to the
riblets than in the trough middle.
On late postnuclear whorls the pattern of sculp-
ture crowding and secondary modification complicates
study of the microspiral elements. But no Pacific
Island species has an apical sculpture that departs
from the patterns outlined above. In extralimital
areas, however, the pattern of apical sculpture is much
more complex, with Charopidae from Australia and
New Zealand, for example, showing a variety of types
(Solem, 1970b, pi. 58, figs. 3-6, for example). Never-
theless, in regard to Pacific Island taxa, the nature of
the apical spiral sculpture is completely correlated
with the anatomically determined family units. It,
together with the nature of the apertural barrier
microarmature (pp. 63-65; Solem, 1973b), form the
only absolute family-level differentiating conchological
criteria.
Surface wear on the shell is the rule rather than
the exception. Frequently the apical whorls will have
sculpture remaining only in the sutures (fig. 21c). It is
not unusual for specimens collected dead to have
nearly all the microsculpture and much of the major
sculpture missing. In such situations, cleaning of the
umbilicus often will reveal perfectly preserved apical
and early postnuclear sculpture. The sculpture is
present in both lower and upper parts of the whorls. If
transported by a stream of water, the umbilicus may
hold an air bubble, while after silting of the opening,
the umbilical shell surface is protected from abrasion
and acid etching. Even fossils usually have unworn
patches of sculpture somewhere on the shell surface or
in the umbilicus.
Other sculptural elements
Additions to the basic sculpture appear
macroscopically (lOOx magnification) as one of two
types, either secondary spiral grooves as in Mau-
todontha zimmermani and all Australdonta taxa
(except possibly A. pharcata), or secondary spiral
cords in some 50 species. Macroscopic interpretation of
the Australdonta sculpture (fig. 124) may be altered
when additional SEM studies are made. Photographs
of Australdonta raivavaeana (fig. 23) show a tendency
towards formation of "spear-point" extensions on the
microradials in the supra-sutural region and irregu-
larly spaced undulations on the microradials as they
traverse the lower whorl surfaces. Whether these are
caused by undulations ( = grooves) in the shell surface
or by growth changes in the ribbing is unknown.
Unquestionably, a multitude of phenomena are
gathered under the heading of secondary spiral
cording. In species such as Thaumatodon corrugata
(fig. 196e), Libera garrettiana (fig. 177c) and Endo-
donta binaria (Pfeiffer) the development of low spiral
cords is obvious. In others, such as Nesophila capillata
(Pease), Libera umbilicata (fig. 178c), Libera bur-
satella bursatella (Gould) (fig. 31a), and Nesodiscus
FlG. 27. Sculpture of Mautodontha (M.) aoraiensis. Station 863,
Mt. Aorai, Tahiti. BPBM 145536 : a, apical sculpture (ca. 300X); b,
early postnuclear sculpture, note wavy microspirals (ca. 1,000 X ).
taneae (Garrett) (fig. 31c, d), I cannot say whether the
protrusions of the riblets result from the addition of
very low spiral cords or represent upward protrusions
of the riblets themselves. Gambiodonta agakauitaiana
(fig. 22d-e) does seem to have low and very broad
spiral cords producing the waved effect in the
microradial riblets. Aaadonta (figs. 28c-e; 29b) seems
to have small knobs on the microradial rib tops that
appear as continuous cords under light microscope
magnification. Throughout the text all of these
phenomena are called "secondary spiral cording."
While different structures are involved, reference of
more than a few species to any particular type of
secondary spiral sculpture is impossible without much
additional use of the scanning electron microscope.
FIG. 28. Sculpture of Aaadonta constricta constricta
(Semper). Station 201, Peleliu, Palau Islands. BPBM 159943:
a, entire shell (ca. 50 X ); b, sculpture of apex and postnuclear
whorls (ca. 100X ); c, detail of dividing line between apical and
postnuclear sculpture (ca. 300x); d, apex and first
postnuclear whorl, note spiral "beads" on postnuclear whorl
(ca. 300 x); e, suture between apex and first postnuclear
whorl, for size compare triangular bit of dirt on apex with d
(ca. 1.000X).
38
PATTERNS OF MORPHOLOGICAL VARIATION
39
FIG. 29. Sculptural details on Aaadonta constricta constricta. Station 201, Peleliu, Palau Islands. BPBM 159943: a, spiral cords on apex,
note irregular, wavy nature of light cords and broadly waved, lower radial growth wrinkles (ca. 3,000 X); b, detail of postnuclear microradial
riblets (ca. 3,000 x).
Such secondary sculpture may be present on only
part of the shell surface, all of the shell surface, or
vary from specimen to specimen of a species. Appear-
ance of secondary cording is not random, with only
Orangia maituatensis, O. sporadica, and Opanara
fosbergi of the 24 Rapan taxa having sculpture. Five of
eight Gambiodonta and 8 of 12 Anceyodonta from
Mangareva have cording. Eleven of 19 Libera and 5 of
11 Taipidon contrast with only 1 of 15 Minidonta and
2 of 17 Mautodontha having raised secondary spiral
sculpture. Some species with secondary spiral sculp-
ture are seen in Cookeconcha, Endodonta, Nesophila,
Thaumatodon, Pseudolibera, and Kleokyphus.
Although 62 of 179 species-level taxa (34.6 per
cent) have at least partial development of secondary
spiral sculpture, I found no obvious correlations
between development of such sculpture and other shell
features. The mean adult size of taxa with such
sculpture is 4.03 mm. compared with a mean of 4.18
mm. for those without secondary spiral sculpture. The
latter category includes a higher percentage of those
species lacking major ribbing (23.5 per cent as opposed
to 15 per cent for those with secondary spiral cording).
Since these are generally the larger species, I suspect
the minor size difference is accounted for by this bias
and does not signify any significant difference. Possi-
bly strong secondary spiral cording in such species as
Thaumatodon corrugata and Libera garrettiana is a
substitute for lost major radial sculpture.
Patterns of variation
Variation in the major ribbing involves rib width,
rib spacing, and reduction or loss of the sculpture.
Most of the smaller species have the individual major
ribs narrow, sharply defined and with almost vertical
sides that flare outward just before the whorl surface.
With increasing shell size, the degree of basal flare is
accentuated. Finally, in several very large species such
as Gambiodonta grandis and G. agakauitaiana (fig.
22) the major ribs become low swellings on the shell
surface. They show scarcely any clear lateral demar-
cations. No meaningful measurements of rib width are
possible in the latter situation, while the small size
and relatively great surface relief of most species
defeat any attempt at measuring individual rib widths
when they are sharply defined. Considerable effort has
been expended in indicating relative rib width in the
illustrations prepared under my direction (MM, SH,
SG, PR). The Bernice P. Bishop Museum drawings
(YK) indicate only rib spacing and give no indication
of rib width. Only general discussion of when widening
of the ribs has occurred is presented in this report.
Adequate quantification proved impossible. Usually
this change is correlated with size increase, although
the quite small Thaumatodon hystricelloides
(Mousson) (fig. 197d-e), T. euaensis (fig. 194a-b), and
T. vavauensis (fig. 196a-b) have broadened ribs.
Little agreement exists among malacologists
concerning how to measure or the utility of rib counts.
R. A. Cumber (1960, 1961, 1962, 1964) made consid-
erable use of rib counts in analyzing geographic
variation in New Zealand charopid land snails.
Working primarily with species where there is a sharp
break between nuclear and postnuclear sculpture, he
has demonstrated least variability in counts obtained
from the first or second postnuclear whorl. Successive
whorls have noticeably larger standard deviations and
standard errors. Most workers have counted ribs on
40
SOLEM: ENDODONTOID LAND SNAILS
FIG. 30. Apical microsculpture of: a, Cookeconcha nudus (Ancey). Kawiki, Hawaiian Islands. FMNH 46422. 300 X; b, Cookeconcha
(lecussatulus (Pease). West Maui, Hawaiian Islands. FMNH 46605. 300X; c-d, Cookeconcha hystrix (Pfeiffer). Hawaiian Islands. FMNH 46444;
c. apex at 300 x ; d, apex-postapical sutural area at 1,000 x. Note periostracal setae on postnuclear sculpture in b.
the last complete whorl of growth. Cumber's method
reduces intrapopulational variation, but makes a
convenient index of rib spacing difficult to calculate. It
also depends on having a clearly delineated nuclear-
postnuclear boundary.
Species of Endodontidae have the apical sculpture
continuing onto the postnuclear whorls, with at most
a break in spacing that is very difficult to detect.
Figures 21a, 27a, and 30a show typical examples where
there is no change. Only in Aaadonta (fig. 28c) is a
clear change visible. A practical problem of
postnuclear whorl-limit recognition exists in the
Endodontidae and would prevent use of Cumber's
methods. The abundant material available for study
was an even greater problem, since counting 60-200
ribs on each shell is quite time consuming. During
post-reproductive and gerontic growth there is usually
considerable crowding of the major ribbing. Frequently
the last few ribs on the body whorl are highly
irregular.
Rib-count measurements in this study were
restricted to adult shells. In the majority of examples
there was no clear nuclear-postnuclear whorl bound-
ary, either because of growth continuity or surface
PATTERNS OF MORPHOLOGICAL VARIATION
41
FlG. 31. Apical and postnuclear sculpture of Libera bursatella bursatella (Gould) and Nesodiscus taneae (Garrett): a, Libera b. bursatella.
Station 863, Mt. Aorai, Tahiti. BPBM 142059, sutural area between apex and first postnuclear whorl, note very weak microspiral riblets (ca.
300 x); b-d, Nesodiscus taneae. Borabora, Society Islands. FMNH 91853 ex Fred Button; b, shell apex, note broad radials and very fine and
crowded spirals (ca. 300X); c, postnuclear sculpture with reduced major ribbing (ca. 100X); d, detail of postnuclear suture showing rib
denticulation of lower whorl (ca. 300 X ).
erosion. Rib counts were made on the body whorl (fig.
32a) both to provide a convenient size dimension, shell
diameter, for calculating rib spacing and because exact
delineation of early postnuclear whorls was impossible.
Rib counts were made on about 40-50 per cent of
the total adult specimens available. Since the complex
apertural denticles found in virtually all Endodontidae
provided criteria for species discrimination, detailed
analysis of rib-count variation was restricted to a few
large samples and the few situations involving subspe-
cific taxa. These provide guidelines for interpreting
variation in smaller samples. For every species where
rib counts could be made, at least 25 per cent of the
available adults were checked and species means
calculated, provided less than 75 individuals were
42
SOLEM: ENDODONTOID LAND SNAILS
FIG. 32. Method of sculptural measurements in the Endodon-
tidae: a, raw rib count with shell diameter (A-B) and body whorl
sutural diameter (C-D) measurements indicated; b, area on body
whorl (A-B) used in determining rib spacing and microriblet counts.
involved. If larger numbers were available, about 50
specimens were used. In the Charopidae, where most
species lack the apertural denticles, far more attention
was paid to shell sculpture variation.
Rib-count variation in local populations of
Orangia cookei cookei (table LXXXVIII), Rhyso-
concha atanuiensis and R. variumbilicata (table
LXXXIV), plus Opanara areaensis (table LXXX)
indicates only minor variation between populations of
the same species or subspecies. The standard errors in
these tables are consistently larger than those of
Cumber (1960, p. 100) for early postnuclear whorl rib
counts comprising the same order of magnitude. This
reflects the variation added by grouping shells showing
only a short section of gerontic rib crowding with
those having up to one-quarter whorl of gerontic
growth. While extending the upper range of the
normal distribution curve and thus increasing the
standard error, such grouping does not seem to have
altered the usefulness of these counts. In a sample of
57 Opanara areaensis, for example, the frequency
distribution of rib counts is moderately skewed (table
XII). The skewness of any such frequency distribution
will depend on the mix of barely adult and gerontic
shells. Since even the large sample of Libera fratercula
rarotongensis showed a slightly skewed normal dis-
tribution (figs. 1-4) quite comparable to that cited
above, I have proceeded on the assumption that the
samples of rib counts are approximately equally
skewed unless a lack or surplus of gerontic individuals
was noted during measuring. At the level of statistical
analysis involved, the error introduced by this variable
does not seem objectionable.
The major ribs are continuous from the parietal-
palatal margin across the periphery, into the umbilicus
and up to the columellar-parietal suture. The distance
(= shell diameter) from lip edge periphery to the
periphery on the opposite side of the shell (fig. 32a, A-
B) obviously is greater than from the parietal-palatal
suture on one side to the other side (fig. 32a, C-D), yet
the rib number is identical. Thus any measure of rib
spacing is going to be arbitrary. The ribs are more
crowded at the sutures than they are on the periphery,
yet they are identical in number and only slightly
different in individual rib width at these two extremes.
For ease in computation and expression of the zone of
major environmental contact, I have chosen an index
of rib frequency calculated from the raw rib count and
the shell diameter. This is expressed as ribs/mm, on
the body whorl. For each specimen this index was
calculated by the following formula:
Ribs/mm. =
rib count on body whorl
•n x shell diameter in mm.
There is an inaccuracy introduced by computing the
circumference of a circle where the actual structure is
TABLE XII. - RIB COUNTS IN OPANARA AREAENSIS
FROM STA. 383
Ribs
45-49
50-54
55-59
60-64
65-69
70-74
Frequency
1
15
9
8
1
PATTERNS OF MORPHOLOGICAL VARIATION
43
one volution of a logarithmic spiral, but the same rib
number would hold for both dimensions. Calculation
of the growth curve for each specimen or species was
impractical, so I have opted cheerfully for simplicity
and slight inaccuracy. The bias is equally toward too
great an outer whorl distance. An additional in-
accuracy results from combining gerontic and pre-
gerontic whorl sections with their quite different rib
spacings. The frequency distribution for ribs/mm,
(table XIII) in the same set of O. areaensis shows
TABLE XIII. - PATTERN OF RIB SPACING IN
OPANARA AREAENSIS FROM STA. 383
Ribs/mm. Frequency
4.75-5.00 2
5.01-5.25 8
5.26-5.50 16
5.51-5.75 8
5.76-6.00 9
6.01-6.25 8
i
6.26-6.50 4
6.51-6.75 2
even more pronounced skewness, but is typical for
measured material. The assumption is made that the
same degree and direction of bias exist unless obvious
departures were noted either during measurement or
initial statistical analysis. Despite the inelegance of
this index, it serves to differentiate closely related taxa
and provides some data averaging out the number of
ribs per unit distance on the shell periphery. The
pattern of pregerontic rib spacing is fairly regular, but
there are noticeable variations in distance between
ribs. Some are caused by injuries, but most have no
obvious explanation. As with the Diplommatina
studied by Berry (1962), these probably reflect micro-
environmental moisture or food fluctuations. For
convenience, I have indicated these by stating the
approximate width of the interstice compared with the
breadth of individual ribs. These observations were
taken from the body whorl periphery with the shell
positioned for a side view. This area is approximately
three-quarters of a whorl behind the aperture and well
before the zone of gerontic rib growth (fig. 32b). A
visual estimate of "one to two times," or "three to four
times" their width was made to encompass variation
observed over about one-eighth of the body whorl.
* *
* * *
•**.* :•*
*
* *
- * *
**
FIG. 33. Correlation between rib count and shell diameter in
Opanara areaensis areaensis from Station 383.
There is also variation in the number of micro-
radial riblets between each pair of major ribs. While
the microradials often are close to the resolution limit
for the stereoscopic binocular microscope at 100 X
magnification, they can be counted. Variation in major
rib spacing adds to the variation in microrib counts. At
the same time that major rib width in relation to the
interstices was estimated, I counted the number of
microradials present between crowded and more
widely spaced ribs on the same portion of the body
whorl (fig. 32b). The observed range is cited as "two to
r
I'M
650
625
I 600
5.25
• 01
50 55 60 65
Ribs
80 85
FIG. 34. Correlation of ribs and ribs/mm, in Opanara areaensis
(all adult material).
44
SOLEM: ENDODONTOID LAND SNAILS
TABLE XIV. - CORRELATION OF MICRORADIAL COUNTS WITH MAJOR RIB COUNTS
AND SHELL DIAMETER IN THE ENDODONTIDAE
Estimated
Number of
Radial Riblets
1-2
Number
of Taxa
Median
Group
Rib Count
250
Mean and
Range of
Group Rib Count
231.7(195-250)
Median Shell
Diameter
in Group
2.15
Mean and Range
of Shell Diameter
in Group
2.40(1.97-3.07)
2-4
150
145.1(60.8-225)
3.79
3.62(1.73-5.17)
3-5
19
113
114.1(61.8-250)
3.27
3.33(2.25-6.29)
4-6
27
94
97.8(60.6-178)
3.60
3.64(2.16-6.72)
5-8
36
78
85.9(40.3-202)
3.36
3.56(1.68-6.59)
6-10
18
67
70.2(41.0-108)
3.84
3.85(2.68-5.79)
8-12
25
61
58.9(19-109)
4.02
4.11(2.00-8.46)
four" or "five to eight" radial riblets and is based on
observation of both specimens with visually crowded
major ribs and visually more widely spaced major ribs
whenever abundant material was available. The cited
figures are estimates and do not represent averaged
data.
In summary, basic data recorded for each speci-
men consisted of raw body whorl rib count and an
index of rib spacing calculated from the shell diameter.
For each species, based upon observations of a few
specimens, estimates were made as to the number of
microradials between each pair of major ribs and an
estimate of relative rib-interstice width on the first
portion of the body whorl. The presence or absence of
secondary sculpture was noted and any progressive
changes in the postnuclear sculpture during ontogeny
were recorded in the written diagnoses.
TABLE XV. - SHELL DIAMETER AND RIB SPACING IN THE ENDODONTIDAE
Median
Ribs/mm.
LESS THAN 2
2.00-2.99
3.00-3.99
4.00-4.99
5.00-5.99
6.00-6.99
7.00-7.99
8.00-9.99
10.00-12.99
13.00-19.99
MORE THAN 20
4
9
9
11
8
19
11
20
22
15
5
leU
iameter
Mean and Range
of Shell Diameter
6.40
7.26(4.28-12.26)
4.98
4.91(3.06-7.30)
4.96
5.28(3.88-7.60)
4.51
4.60(2.77-6.59)
4.12
4.03(2.90-4.89)
3.74
3.61(1.87-4.73)
3.36
3.87(2.61-5.42)
3.07
3.32(1.79-6.72)
3.04
2.97(1.73-5.17)
2.84
2.97(1.68-4.61)
2.15
2.49(1.83-3.43)
Although there is a general pattern of little
difference between populations in respect to rib counts
and rib spacing, variation within a particular popu-
lation is rather large. Using material of Opanara
areaensis as an example, Figures 33 and 34 indicate
the typical situation. Rib count does increase with
shell diameter (fig. 33), but the correlation (r = 0.56)
is not significant. When rib spacing is correlated with
raw rib count (fig. 34), the relationship is slightly
tighter, but the variation is large enough that
individual specimen measurements have little pre-
dictive value. The low inter-populational variation
reflects the fact that nearly all species of Endodon-
tidae are restricted to the leaf litter zone in dense
undisturbed forests. Variation in the moisture and
temperature environment under these conditions is
minimal, hence ecophenotypic changes are predicted to
be minor.
Correlated variations
While statistical treatment of data for individual
populations was done in many cases, generally only
the mean and range were calculated for each sub-
species and species. Although considerable analysis of
interspecific sculptural variation patterns has been
undertaken, full elucidation of this will be deferred
until data from the Charopidae and extralimital taxa
are available for comparison. Relationships between
shell size, niche and surface sculpture are complex.
Only a few of the more obvious factors will be
discussed at this time.1
A. Rib spacing. — Within the family Endodon-
tidae, 140 species-level taxa retain major radial ribs on
the entire body whorl. While in a few of these taxa
only very worn or fossil shells were available, for the
Data on Priceconcha and Thaumatodon spirrhymatum
(Solem. 1973d) are not included below.
TABLE XVI. - CORRELATION BETWEEN RIB SPACING AND SHELL DIAMETER IN THE ENDODONTIDAE
Ribs /mm.
X Diameter
ca
H
co
CO
0)
ON
ON
CM
O
O
CM
ON
ON
1
O
o
•
ON
<f
O
O
<•
ON
ON
1
0
O
ON
1
o
o
•
v^
0
o
•
r^
ON
0
O
CO
ON
ON
•
CM
t-t
1
0
H
ON
ON
•
ON
H
1
.H
O
CM
1-t
0)
O
1.50-2.00
2.01-2.50
2.51-3.00
3.01-3.50
3.51-4.00
4.01-4.50 2
11 38 43
221244
4.51-5.00
124211 3
5.01-5.50
21 11
5.51-6.00
11 1
6.01-6.50
6.51-7.00
i 2 «
i i
7.01-7.50
7.51-8.00
^
i
i
r
Over 8 2
-b
45
TABLE XVII. - SIZE AND DEGREE OF SCULPTURE REDUCTION IN LARGER ENDODONTIDAE
Major ribs present subapically,
absent on lower spire and
body whorl
Major ribs absent, microsculpture
well developed
X D
Kondoconcha othnius 4. 06 Nesodiscus obolus f. obolus
X D
4.76
4.85
5.12
5.17
5.50
5.62
6.47
Libera spuria 4. 83 Libera garrettiana
Nesodiscus taneae 4. 89 Nesodiscus f. acetabulum
Endodonta laminata 6.22 Nesodiscus huaheinensis
Libera turn uloides 6.51 Nesodiscus obolus f. celsus
Nesodiscus magnificus 11.19 Nesodiscus cretaceus
Nesodiscus f ictus
Shell surface smooth except
for growth wrinkles
X D
Endodonta concentrata 5. 06
Nesodiscus fabrefactus f. piceus 6. 06
Libera heynemanni 6. 52
Endodonta lamellosa 6.61
Endodonta kamehameha 6. 91
Endodonta marsupialis 7.20
Nesodiscus fabrefactus 7.46
Endodonta fricki 8. 99
Nesophila tiara 11.29
46
PATTERNS OF MORPHOLOGICAL VARIATION
47
great majority it was possible to record the basic data
as outlined above. Tables XIV and XV present the
results of tallying combinations of variables. In Table
XIV species have been grouped as to the estimated
number of radial riblets, then rib counts and diameters
tallied for each group. There is a clear pattern for rib
growth vector mean that the last few whorls show
little increase in diameter when compared with a
normally coiled shell. The offset in the chart of these
species results from growth alteration. C. jugosus and
P. concava are very large species with few and quite
widely spaced radial ribs.
TABLE XVIII. - SHELL SIZE AND SCULPTURE REDUCTION IN POLYNESIAN ENDODONTIDAE
Shell diameter
3. 00 mm. or less
Total taxa
42
Taxa with
reduced
sculpture
Per cent of taxa
with reduced
sculpture
3.01-4.75
82
4.9
more than 4.76 mm.
44
22
50.0
1. Two species, Pseudolibera lillianae and Kleokyphus hypsus,
are based on single adults whose surface is so worn that
ribbing pattern is unknown.
counts to drop drastically between groups with an
increase in number of radial riblets. The same groups
show very little change in shell size as measured by
both mean and median diameter. Only where the
number of riblets drops to one or two is there a
marked decrease in diameter, and only where the
number rises to between 8 and 12 is there an average
increase in shell size.
The relationship between rib spacing and shell
diameter (tables XV and XVI) is not quite so tight.
Although the median diameter shows a simple pattern
of larger shells having fewer ribs/mm., the range
within each group is large and mean shell diameter
departs from the even scale.
Much of this departure can be explained through
reference to Table XVI. Most species clump within a
relatively narrow transverse zone. The exceptions in
the area marked "B" are Mautodontha boraborensis
(Garrett), Australdonta pharcata, and A. ectopia. All
three are species at or near the Nesodiscus level of
specialization, which is characterized by increased size,
great rib crowding and reduction, plus umbilical
widening. Other taxa on the Nesodiscus level lack
major radial ribs on the body whorl and hence are not
included on this chart. The 11 species in area "A"
include eight Libera, Gambiodonta grandis, Cooke-
concha jugosus (Mighels), and Planudonta concava.
The Libera and Gambiodonta have greatly altered
growth patterns because of brood-chamber formation.
These changes produce a low diameter in relation to
shell volume. The elevated spire and strong downward
B. Rib reduction. — While major radial ribbing is
present in most taxa, many species have the ribs
reduced or absent. This state is arrived at in a number
of different ways, the simplest being complete loss of
both apical and postnuclear major radial ribs without
any alteration in the microsculpture. This is restricted
to the only Micronesian endodontid genus, Aaadonta.
All nine taxa in this genus completely lack major
ribbing, but retain typical microsculpture with no
suggestion of size decrease.
In a few species, Thaumatodon euaensis, T.
subdaedalea, T. corrugata, and Libera subcavernula
(Try on, 1887), the major radial ribs are prominent on
the spire and usually well onto the body whorl, but
before the actual beginning of gerontic growth they
fade into irregularity and thus cannot be counted with
any accuracy. Except for the Libera, these are quite
small species.
Progressive sculpture reduction can be divided
into three stages: 1) retention of major ribs on the
upper spire with their loss on the lower spire and body
whorl; 2) complete loss of major ribs but retention of a
well-developed microsculpture that is clearly visible at
less than 50 X magnification; and, finally, 3) reduction
or loss of the microsculpture producing a smooth
surface, even at 50 X magnification, except for gerontic
growth wrinkles. Table XVII lists the species belong-
ing to each category in ascending size order. While
first glance suggests that this may be a pure phyletic
phenomenon, since 20 of 22 taxa belong to Nesodiscus,
Endodonta, and Libera, Table XVIII demonstrates
48
SOLEM: ENDODONTOID LAND SNAILS
1500
12 50
10 00
9.00
800
700
600
500
4.00
350
300
2 75
2 50
2.25
200
1 75
1 50
1 25
D
Species of Mmidonta 9
Anceyodonta "if
Gambiodonla I I
D
D
D
D
D
D
*,*
I I
I
I
I
I
I 1
I
I
I I
I
I
j I
i.o
1.5 20 25 3.0 35 4.0 5.0 6.0 70 80 9.0 10.0
Mean Ribs /mm.
125 15.0 17.5 20.0 25.0 30.0 35.0 40.0
FIG. 35. Relationship of mean shell diameter to major rib spacing in species of Mmidonta, Anceyodonta, and Gambiodonta on a double log
scale.
that rib reduction is a size-correlated phenomenon. Of
the 22 large species retaining prominent radial ribbing,
there are 11 species of Libera, 5 Gambiodonta, 4
Cookeconcha, and single species each of Taipidon and
Planudonta. Hence concentration of the species with
reduced sculpture in a few genera parallels the
restriction of large size to a few phyletic lines. Phyletic
factors are involved, since only 4 of 15 large Libera, no
large Gambiodonta, but all large Nesodiscus and
Endodonta show sculpture reduction. The groupings
in Table XVII represent similar stages in different
phyletic series and no absolute correlation between
size and stage of ribbing reduction was expected.
Nevertheless the tendency for larger size to correlate
with a greater degree of sculpture reduction in obvious.
On an overall basis (table XVIII), major rib reduction
clearly is size associated, since there is a tenfold
increase in rib reduction frequency once a size of 4.75
mm. is surpassed.
Within the Minidonta-Anceyodonta-Gambiodonta
lineage there is a clear pattern of change in rib spacing
with size increment. When plotted on a double log
chart (fig. 35), the pattern in the larger species is
highly correlated, although in the smaller species there
is greater scatter. The latter is the result of drastic
alterations in shell shape, such as the flattened spire
and widely open umbilicus of Anceyodonta andersoni.
The above discussion has been limited to situ-
ations where sculpture is reduced evenly over whorl
surfaces on progressively larger parts of the shell.
Sculpture reduction on only part of the whorl surface
with retention of major ribbing on other sections is
equally possible, but has occurred less frequently.
Two species, Endodonta binaria (Pfeiffer, 1856)
from Kauai, Hawaii and Kleokyphus callimus from
Makatea have the sculpture reduced above the body
whorl periphery, but remaining prominent on the shell
base. In E. binaria the broadly rounded major ribs are
prominent on the upper spire, then gradually diminish
in height, fading out well before the body whorl, but
remaining prominent below the periphery up to the lip
edge. K. callimus has normal ribbing below the shell
periphery, but above the periphery the major ribs are
scarcely larger than the microradials and do not
change in size from the apex to lip edge.
Seven large species have the reverse situation,
with major radial ribbing drastically reduced below the
whorl periphery (table XIX). Except for L. cookeana,
all these species have keeled or protruded peripheries.
Such rib reduction is of obvious selective value. During
growth the parietal wall callus must be deposited on
the lower outer palatal surface of the preceding whorl.
This callus either must be thick enough to cover
PATTERNS OF MORPHOLOGICAL VARIATION
49
completely the major ribs or else the ribbing must be
absorbed prior to callus formation. Either tactic is
wasteful in terms of energy utilization when the ribs
are large. Rib building requires calcium extraction
from the environment and then energy expenditure in
deposition. Subsequent energy use to dissolve and
resorb or to completely cover the ribs with additional
calcium layers would be considerable. Size reduction of
the subperipheral ribbing thus increases the snail's
efficiency. Considering just the 14 largest species that
retain major radial ribbing (table XIX), those with
sub-peripheral rib reduction are noticeably larger than
those retaining large sub-peripheral ribs. The disparity
would be greater except for Gambiodonta mirabilis,
which is the smallest species of the group, yet shows
dramatic rib reduction (fig. 188c-d). The very high and
prominent supra-peripheral ribs in this species and its
development of very prominent protruded keels in-
dicates the energy-use advantage in having the sub-
peripheral sculpture reduced in size.
When the above data is combined with that in
Table XVII, the extent of size correlated rib reduction
is even more marked. Combining the seven species
cited above with the 22 species over 4.75 mm. in
diameter that show both sub- and supra-peripheral rib
reduction, 29 of the 44 taxa (65.9 per cent) comprising
the larger endodontid species show at least partial rib
reduction. The six smaller species showing rib reduc-
tion referred to in Table XVIII consist of the three
Thaumatodon with rib reduction on the last part of
the body whorl, the two species showing only supra-
peripheral rib reduction (Endodonta binaria and
Kleokyphus hypsus) plus the peculiar Rapan species
Kondoconcha othnius.
An exception to this pattern is seen in Price-
concha tuvuthaensis Solem (1973d). Here virtually all
sculpture is absent from the apex and spire with only
traces of micro-reticulations and vague larger pe-
ripheral irregularities suggesting major rib remnants
on the body whorl. Since its maximum recorded size is
only 4.54 mm., the extent and completeness of
sculpture reduction is unusual. Probably this corre-
lates with a habitat shift, since the live collected
individuals were obtained on the trunks of trees up to
10 ft. above ground level. Only a few Cookeconcha and
Libera bursatella bursatella have been taken above
ground level, with the remaining species litter or
subcortical forms.
Data concerning the reasons behind this pattern
of rib reduction once a size of about 4.75 mm. is
obtained will be presented elsewhere in conjunction
with discussion of the Charopidae and taxa from other
areas.
In the above discussion of surface sculpture, two
patterns emerge. First, that rib spacing is determined
by an interaction of rib width, distance between ribs,
number of microradial elements, shell size, and degree
of spire protrusion in non-brood chamber taxa. Within
TABLE XIX. - SHELL SIZE AND SUBPERIPHERAL
RIB REDUCTION IN LARGER ENDODONTIDAE
No subperipheral rib reduction
Species
Libera fratercula fratercula
Libera recedens
Planudonta concava
Libera streptaxon
Cookeconcha jugosus
Libera fratercula rarotongensis
Libera gregaria
Average X D = 6.09
Subperipheral rib reduction
Gambiodonta mirabilis
Gambiodonta turn Ida
Pseudolibera lillianae
Libera incognata
Libera cookeana
Libera jacquinoti
Gambiodonta grandis
Average X D = 7.68
X D
5.60
5.66
5.79
6.06
6.18
6.59
6.72
X D
5.54
6.18
6.42
7.30
7.60
8.46
12.26
broad limits and more closely within particular
phyletic lineages, larger species will have fewer major
radial ribs per unit distance on the periphery.
Secondly, reduction or loss of both macro- and micro-
sculptural elements is associated with increased size.
These trends can be seen in relation to particular
phyletic situations. On Rarotonga Libera fratercula
retains large radial ribs, L. subcavernula has ribbing
reduced on the body whorl, and L. tumuloides has lost
the major ribbing completely. The latter two species
were restricted to interior valleys of Rarotonga and
presumably derived from the coral boulder zone L.
fratercula. While the Rarotongan shoreline race of L.
fratercula is quite large (mean diameter 6.59 mm.), the
nominate race from the offshore islets of Rarotonga
and elsewhere in the Cook group is smaller (mean
diameter 5.60 mm.) than L. subcavernula (6.29 mm.)
and L. tumuloides (6.51 mm.). If L. fratercula
50
SOLEM: ENDODONTOID LAND SNAILS
originated on one of the other Cook Islands and L. f.
rarotongensis is secondarily enlarged, then this forms
a typical "rib reduction-size increase" series.
In Hawaii, the very small Endodonta ekaha-
nuiensis (mean diameter 2.77 mm.) has prominent
ribbing, which is reduced in the larger E. binaria (4.26
mm.), further reduced in E. laminata (6.22 mm.) and
greatly reduced in the other described species, whose
mean diameters range up to 8.99 mm. Nesophila
capillata (Pease) (mean diameter 4.46 mm.) has fairly
prominent radial ribs, while the much larger (mean
diameter 11.29 mm.) N. tiara (Mighels) has weak ribs
on the upper spire, but lacks major sculpture on most
of the surface although showing growth wrinkles. A
similar series is seen in the Society Island genus
Nesodiscus, where the smaller species, N. taneae
(Garrett) and N. obolus (Gould) (mean diameters 4.89
and 5.08 mm., respectively), retain vestiges or very
crowded radial ribs; species of intermediate size, N.
huaheinensis (Pfeiffer), N. cretaceus (Garrett), and N.
fictus (Pease) have fairly prominent micro-sculpture;
and the very large TV. fabrefactus (Pease) is macroscop-
ically smooth. Only the extremely large N. magnificus,
known from a single very worn adult, departs from
this pattern by apparently retaining moderate sculp-
ture.
Functional significance of sculpture
Such a high percentage of the species probably is
extinct that experimental field work concerning the
relative efficiency of the several sculpture types no
longer may be possible. The sculpture does serve to
break up the shell surface with a series of narrow
protrusions. These are more numerous and closer
together in smaller species than in larger species. A
series of narrow protrusions coming into contact with
moist granular material in the environment is much
less apt to adhere than is a relatively smooth surface.
Since the Endodontidae live in the upper soil and litter
layers, under stones or in rotting logs, and are
constantly touching moist or wet granular materials,
avoidance of surface debris accumulations is a major
problem. The less-than-3-4 mm. species in particular
have to cope with comparative "boulders" that, when
coated with a water film, would tend to adhere
strongly to any passing object. This adds not only to
the weight of shell to be transported by the snail, but
also would increase the volume of the shell and thus
impede movement through narrow crevices. Although
the complex sculpture increases total surface area of
the snail shell, it drastically reduces effective contact
surface area (fig. 24) between the shell and particles in
the environment.
The surface sculpture of the endodontid land
snails seems to be an adaptation to minimize accumu-
lation of trash on the shell. Many minute arthropods
accomplish this by use of waxy surface coatings.
Investigation of the surface properties for the smooth
"zonitoid"— like periostracum in such Holarctic taxa
as Retinella, Zonitoides, Vallonia, and Carychium,
whose basic niche is similar to that of the Endodon-
tidae, but which belong to divergent families, in
contrast to the periostracum of such sculptured taxa
as Discus, Punctum, Striatura, and many pupil-
lids — probably will yield important results. All litter
snails must solve, or live with, the tendency to pick up
particles from the environment. Prominent surface
sculpture seems to be a primary means of minimizing
particle accumulation.
OTHER EXTERNAL SHELL FEATURES
Analysis of body whorl descension and the pattern
of sulcus occurrence require a few comments. As
indicated previously (p. 11), the tendency of the body
whorl to descend more rapidly is one of the characters
used to separate adult shells from juveniles. This
descension is a relative character. It must be measured
against the rate of descension for the spire whorls. If
the spire is secondarily elevated, then a greater degree
of body whorl descension must occur before it becomes
noticeable. If the spire is secondarily flattened, then
the relative degree of body whorl descension will be
magnified in comparison. No practical direct measure
of body whorl descent was developed. Only relative
coding was possible.
As a result, the few strong correlations between
body whorl descension and shell parameters can be
interpreted as the result of secondary modifications.
The only species with abrupt body whorl descension
are Libera recedens Garrett (figs. 170, 175e), Libera
retunsa (Pease) (fig. 178e), and Libera streptaxon
(Reeve) (fig. 179a). In these species the normal Libera
shape is altered into a shell with flattened spire. The
abrupt body whorl descension results from problems of
umbilical narrowing during brood chamber closure.
Those species with strong body whorl descension tend
in part (Rikitea insolens, fig. 150; Planudonta con-
cava, fig. 149a; Australdonta pharcata, fig. 137b) to be
flat-spired taxa, although some (Kleokyphus hypsus,
fig. 95e; Mautodontha saintjohni, fig. 75b; Opanara
TABLE XX. - BODY WHORL DESCENSION AND SHELL SIZE
X and SEM
of:
Height
Diameter
H/D ratio
Whorls
Spire 1
protrusion
Number
of taxa
Body Whorl Descension
None Slightly Moderately
2.60+0.17 2.11+0.12 1.89±0.08
U. 75+0. 28 U.03±0.21
0.529+0.011
5.6U+0.10
3.70
0.532+0.017
6.01+O.lU
k.66
Uk
67
3.52+0.13
0.539±0.010
5. u i»jjo. 09
3.61
57
1. X of code states, when "1" is depressed and "7" is
spire protrusion greater than body whorl width
PATTERNS OF MORPHOLOGICAL VARIATION
TABLE XXI. - BODY WHORL CONTOUR AND RATE OF DESCENT
51
Body whorl
contour Not
Rounded 9
Angled 3
Barely protruded 8
keel
Strongly protruded 22
keel
Knife-edge 2
keel
altiapica, fig. 105c) have elevated spires and do show a
major change in coiling pattern.
Those 44 species classified as showing no increase
in body whorl descension (table XX) had significantly
larger size, more whorls, and a higher spire protru-
sion/body whorl width ratio than those with slightly
or moderately deflected body whorls. There was no
alteration in the H/D ratio. This suggests that body
whorl descension may be insignificant in its overall
effect on shell proportions.
Further analysis (table XXI) shows that the size
correlations are probably secondary to body whorl
contour features. The combination of marked keel
development and no body whorl descension is
strikingly different from the pattern where a rounded
body whorl is associated with slight to moderate body
whorl descension. The two keeled taxa with abrupt
body whorl descension are Libera recedens and L.
streptaxon. In both cases there are space problems
with brood chamber narrowing that require quick
inward growth. This can be achieved most readily by
abrupt body whorl deflection. Earlier (p. 23) it was
shown that keel development led to larger size, so that
the greater size increase should not be attributed to
the descension correlation. From the standpoint of
mechanical efficiency, attachment of the parietal-
palatal margin to the keel edge of the previous whorl
would be simplest. In Planudonta concava (fig. 146)
the descent of the body whorl has resulted in partial
transfer of the parietal wall onto the columellar wall
region. Similarly the parietal wall sections in Libera
streptaxon and L. recedens are detached and extend to
narrow the umbilicus. Since parietal wall deposition
involves smoothing the previous surface by either
covering or partly resorbing the ribs, then secreting a
relatively thin callus, the detached parietal wall areas
are less substantial and complex than the normal
columellar surfaces. Unless there are major advantages
to this happening, maintainence of mechanical
strength in the shell would favor retaining a whorl
attachment that avoided parietal wall detachment.
Body whorl descension
Slightly Moderately Strongly
^5 52 8
9 2
7 2
Abruptly
Following the keel edge accomplished this, and
probably prompted the tendency for adult body whorl
descension.
Sulci have developed in a number of taxa, usually
in connection with keel formation. A major exception
to this generalization is the peculiar subsutural sulcus
found in several Anceyodonta. This is not always
present in every specimen; for example see A.
sexlamellata (Pfeiffer) (fig. 86a, c), and the dis-
tribution within the genus is not random. The sulcate
species, A. sexlamellata (Pfeiffer), A. soror, A.
difficilis, A. obesa, and A. subconica (figs. 81d, e; 83;
88a, c; and 89a) are rather high spired compared with
other species in the genus (fig. 82, for example). Only
Anceyodonta ganhutuensis (fig. 81a) among the high-
spired forms lacks the sulcus. It is possible that this
sulcus enables better attachment to the previous
whorl by extending the parietal wall slightly upward,
reducing the sutural depth, and avoiding any altera-
tion in rib height at the suture. As such, this sulcus
could have selective value for the particular species
involved. Other high-spired taxa, such as the various
Nesodiscus (figs. 159-161), Libera (figs. 174-178), and
Aaadonta (figs. 203-204) have the spire whorl relatively
flat sided, while in the sulcate Anceyodonta they are
strongly rounded. Attachment without problems of rib
height is far easier in the flat-sided whorl taxa than in
Anceyodonta.
TABLE XXII. - CORRELATION BETWEEN SULCI AND BODY WHORL CONTOUR
Supraperipheral Subperipheral
Total taxa sulcus present sulcus present
Body whorl
contour
Rounded
lilt
Angled
15
Weak keel
17
Strong keel
29
Knife-edge
keel
It
8
8
16
27
2
1
2
12
28
0
52
SOLEM: ENDODONTOID LAND SNAILS
Formation of supraperipheral and subperipheral
sulci is correlated with keel formation (table XXII).
Virtually all species with keels have prominent
supraperipheral and subperipheral sulci. Only when
the keel becomes so narrow that it is "knife-edge," as
in Endodonta fricki (Pfeiffer) (fig. 167 g), does the
subperipheral sulcus disappear completely. In those
species with a rounded body whorl, very few show
clear sulci. Orangia cookei cookei (fig. 123a) has a
distinct supraperipheral sulcus, while other species in
the same genus are distinctly keeled, for example O.
maituatensis (fig. 123e). Opanara dupUcidentata (fig.
102) is the only species in its genus to show a sulcus,
as is Mautodontha ceuthma (fig. 72e) and Anceyo-
donta sexlamellata (Pfeiffer). Most Australdonta and
all other Aaadonta are keeled, so that the sulci of
Australdonta pseudplanulata (fig. 127e) and Aa-
adonta pelewana (fig. 207b) are not surprising.
It may be that the development of a supraperi-
pheral sulcus is a preliminary to angulation followed
by keel formation, but the evidence needed to solve
this question is not available. I consider it quite
possible that such round body whorl, sulcate taxa as
those mentioned above could represent either states
preliminary to keel formation or taxa that have
secondarily rounded body whorls. Frequently juvenile
examples will have much more sharply angulated or
keeled peripheries than do adults of the same species.
The concentration of sulcus formation in keeled taxa
does suggest a causative relationship, but much more
evidence is needed before the questions can be
answered.
APERTURAL BARRIERS
Perhaps the most characteristic feature of the
endodontid shell is the narrowing of the apertural
ANTERIOR
POSTERIOR
Parietals
(PrK
Columellar
(0
FIG. 36. Apertural barrier terminology and numbering system.
Trace barriers are indicated by "tr."
ANTERIOR
lip edge
POSTERIOR
parietal-palatal margin
POSTERIOR
palatal- columellar margin
FIG. 37. Apertural barrier form in the Endodontidae: a, parietal
wall fragment; b, columella with portion of basal lip and broken
upper whorl fragments remaining; c, palatal wall section showing
points of attachment to antepenultimate whorl. All greatly enlarged
and based on Orangia cookei montana. Abbreviations are: PR -
parietal lamellae; C - columellar lamella; P - palatal lamellae.
opening by a series of ridge-like barriers. These are
present even in late embryonic and newly hatched
shells, extend from near or at the lip edge posteriorly
for generally a fraction of a whorl, maintain this
relative position throughout shell growth by a
combination of anterior increment and posterior
resorption, and have a very characteristic superior
microdenticulation pattern.
PATTERNS OF MORPHOLOGICAL VARIATION
53
FlG. 38. Parietal barrier structure in Australdonta degagei
(Garrett) and Mautodontha aoraiensis: a. b, Australdonta degagei
from Station 839, Rimatara, Austral Islands (BPBM 149163); a,
parietal wall in lateral view with anterior portion to left; b,
cross-sectional views through 1st parietal barrier; c, Mautodontha
aoratensis from Station 870, Mt. Aorai Trail, Tahiti, Society Islands
(BPBM 145536). Parietal barriers with anterior end to left (MM)
In a few extremely gerontic individuals (compare
adult and gerontic Minidonta simulata in fig. 70a, d)
the barriers may be greatly reduced from their normal
size, while within both a few species (for example,
Ruatara oparica, figs. 113, 114) and genera (Neso-
discus, figs. 152-161) there has been great reduction or
even loss of the barriers. In many taxa there are trends
for size reduction and splitting of the barriers (for
example, Mautodontha punctiperforata, fig. 76d; Opa-
nara megomphala, fig. 106a, c; Australdonta radiella,
fig. 132a, c; Taipidon centadentata, fig. 144a, b;
Planudonta intermedia, fig. 149c; and the Hawaiian
Nesophila). The correlatives of these trends are
discussed later.
These barriers are analogous to those found in
other land-snail taxa (Solem, 1972c). Each major
phyletic unit shows its own pattern as to ontogenetic
time of appearance and persistence, number, relative
position within the aperture, and terminology applied
to the barriers. The complex barriers and plates of
such groups as the Corillidae (Gude, 1914), Strobilop-
sidae (Pilsbry, 1948, p. 849, fig. 458), Polygyridae
(Pilsbry 1940, p. 959, fig. 384), Pupillidae (Pilsbry,
1948, p. 869, fig. 469), camaenid genus Labyrinthus
(Solem, 1966b, p. 39, fig. 9), and Tornatellinidae
(Cooke and Kondo, 1960, p. 8, fig. 2) differ radically
from those of the Endodontidae (figs. 36-38) and
Charopidae. There is no evidence that they are not
independently derived, although they perform the
same inferred functions of reducing predation on the
snails by making it more difficult or impossible for a
predator to gain access to the retracted animal.
Adoption of a uniform terminology for these diverse
types of barriers would imply homology and serve no
useful function, although retention of the standard
apertural zonation descriptions is justified.
The numbering system and zonation used to
describe the apertural barriers in both the Endodon-
tidae and the Charopidae are shown in Figure 36.
Those barriers located on the parietal wall are termed
parietals (PR). They are numbered from upper right to
lower left in sequence. Junctions of the parietal with
columellar and palatal walls are obvious, but the point
of separation between the palatal and columellar walls
is difficult to define with precision. It is at the
curvature change from basically axial descent (colu-
mellar) to paralleling the plane of coiling (basal
section of palatal). In practice there normally is a
rather sharp point of change that is easily identifiable,
although in a few taxa there are changes in growth of
shell or barriers that alter the positions. For example,
the closed umbilicus of Mautodontha imperforata (fig.
76e, f) and strong lateral compression in Opanara
fosbergi (fig. 107c) effectively shifted the columellar
barrier onto the palatal lip. An equivalent shift of
parietal barriers onto the columellar area would be
possible under such growth distortions as occurred in
Planudonta (fig. 146), Nesodiscus taneae (fig. 152),
and several Libera. In several other taxa, such as
Anceyodonta soror, A. difficilis, A. labiosa, Opanara
areaensis (fig. 104a, c, e), and Ruatara koarana (fig.
113a, b), the columellar barrier's growth pattern
results in its being deflected down onto the basal part
of the palatal wall. The distinction between columellar
and palatal barriers thus is partly subjective and
requires careful attention to unusual alterations in
54
SOLEM: ENDODONTOID LAND SNAILS
shell form or barrier ontogeny before making
comparisons with other taxa. In practice, there usually
is little difficulty in recognizing homologous barriers
within at least a genus. The numbering of palatal
barriers (P) from lower left to upper right is for
convenience.
A more arbitrary distinction is that used between
barriers and traces (fig. 36, tr). The latter frequently
are characterized by being much lower in height,
significantly shorter, only half or a third as long, and
lacking any trace of microdenticulations on the upper
edge. In these circumstances, the distinction is simple
and obvious. In species such as Anceyodonta subconica
(fig. 81d), A. difficilis (fig. 83a), A. soror (fig. 83c, e),
and A. obesa (fig. 89f), the traces are miniature
replicas of the major barriers with microdenticulations
above and similar cross-sectional shape. At the other
extreme, species with reduced and split barriers, such
as Mautodontha punctiperforata, Opanara megom-
phala, Australdonta radiella, Taipidon centadentata,
Planudonta intermedia, and all species of Nesophila
have the major barriers reduced in size nearly to that
of the traces. In other species, such as Priceconcha
tuvuthaensis Solem (1973d, p. 22), only the slightly
raised microdenticulated section that starts three-
eights of a whorl inside the aperture permits dis-
tinguishing the barriers from the traces.
Throughout the discussion and descriptions,
major barriers are referred to as "1st, 2nd, and
3rd," while traces are called "first, second, and
third" as a shorthand differentiation. Similarly,
counts of major barriers are given in numerals
as, 1, 2, 3; traces are spelled out.
Despite the above practical difficulties in dis-
criminating between the major barriers and additional
traces, the general distinction is highly useful and
significant. Decisions in regard to any particular
species involve comparisons with related taxa as well
as direct observations on barrier size, shape, and
microdenticulation.
The occurrence of traces is not random, but
concentrated within a few taxa (table XXIII). Nine
other genera, including such speciose taxa as Austral-
donta, Nesodiscus, and Libera, have no species with
traces. Members of the Minidonta-Anceyodonta-Gam-
biodonta lineage have 76.5 per cent (26 of 34 species
level taxa) with palatal traces, but only 47.1 per cent
(16 of 34) with parietal traces, whereas the Thaumato-
don-Zyzzyxdonta-Priceconcha-Aaadonta species have
40 per cent (8 of 20) with palatal traces and 60 per
cent ( 12 of 20) with parietal traces. The Cookeconcha-
Endodonta group has 33.3 per cent (8 of 24) with
palatal traces, but none with parietals. The sporadic
occurrence of traces in a few other genera is obvious.
Size of shell does not correlate with trace presence or
absence, since species with such traces include the
genera that are smallest (Minidonta, Anceyodonta)
and largest (Endodonta, Gambiodonta) in size. I have
TABLE XXIII. - PRESENCE OF TRACE BARRIERS IN THE EIJDODONTIDAE
Genus
Minidonta
Mautodontha
Anceyodonta
Cookeconcha
Kondoconcha
Endodonta
Gambiodonta
Thaumatodon
Zyzzyxdonta
Aaadonta
Priceconcha
Total species
level taxa
15
17
12
16
2
12
11
It
1
8
7
9
1
9
1
Parietal traces
3
2
7
0
1
0
3
2
1
0
6
7
1
3
1
Number with
Palatal traces
10
5
9
2
1
1
3
0
1
6
7
ll
0
3
1
no explanation as to the functional significance of
traces as opposed to barriers.
Discussion of structural and size variations in the
barriers found in each zone precedes analyses of barrier
growth, microdenticulations, and the overall variation
in barrier numbers and length.
Parietal barriers
The basic shape and positioning of the barriers are
shown in Figures 37 and 38. The typical parietal
barrier (fig. 37a) has the posterior third to half
expanded above (fig. 38a, b) with most of the expanded
section covered with microdenticulations (fig. 39d, e)
that all point toward the apertural margin. The
anterior half to quarter of the lamella has a slenderer
form, is without denticulations, and descends towards
the parietal surface. The manner of this descent varies
with tooth position and between taxa. In Orangia
cookei montana (fig. 37a) the 1st parietal (upper)
descends very gradually until its tip, then plunges
abruptly. The 2nd parietal (lower) has an abrupt
descension just anterior to the denticulated area, then
continues forward as a "thread-like" ridge to its
anterior termination. The lower parietals in Opanara
areaensis areaensis (fig. 39c) have an intermediate
pattern of descension. Australdonta degagei (fig. 38a)
shows a very characteristic pattern in which the 1st
parietal (upper) is a high lamellar barrier and has
gradual anterior descension; the 2nd (middle) has a
shortened posterior denticulated section and a long
"thread-like" anterior section; and the 3rd (lower) is
shortened, lower in posterior height, and with a
proportionately longer anterior extension. This
progressive pattern of height reduction and shortening
of the denticulated section is repeated in most species
and is well demonstrated by Gambiodonta grandis
PATTERNS OF MORPHOLOGICAL VARIATION
55
FIG. 39. Shell sculpture and denticle structure in Opanara areaensis areaensis. Station 474, Rapa Island. BPBM 144651: a, apical sculpture
showing worn area (ca. 3,000x ); b, anterior edge of parietal callus showing method of riblet covering (300X ), note anterior edge of upper parietal
lamella; c, anterior descension of 2nd and 3rd parietals with portion of 1st parietal showing serrations (300 x); d, top portion of 1st parietal
serrated section (ca. l.OOOX ); c, detail of serrations on 1st parietal (ca. 3,000x ).
(fig. 189c). In contrast, some species such as Mau-
todontha aoraiensis (fig. 38c) have the denticulations
extend to within a very short distance of the anterior
end with sharp anterior descension.
Descension of the 2nd parietal barrier is a
convenient index of variability. Table XXIV correlates
the type of descension and number of major barriers
present. There is a tendency towards more rapid
descension with decrease in barrier number, but this is
not nearly as strongly correlated as many other
variations. This is not a size-correlated variable (table
XXV). Larger species with only 2 parietal barriers
tend to have either very sharp anterior descension or a
very long threadlike portion. To some extent this is
56
SOLEM: ENDODONTOID LAND SNAILS
TABLE XXIV. - CORRELATION BETWEEN NUMBER OF PARIETAL BAREIERS
AND DESCENSION OF 2ND PARIETAL BARRIER
Number of
parietals
2
2-3
3-1.
lt-5
many
TOTALS
Sharp
anterior
15
ll
1
Gradual from
middle
10
15
6
31
1/14-1/3 is
threadlike
13
9
5
27
3/8+ is
threadlike
23
25
15
9
6
T8
phyletically correlated, since of the 15 taxa with sharp
anterior descension, 13 are Libera and two are
Cookeconcha. Of the 23 taxa with long threadlike
anteriors, 10 belong to Cookeconcha and Endodonta,
three to Mautodontha, two to Libera, four to
Taipidon and Planudonta, with the other four
scattered among four genera. There is thus ex-
perimentation within genera.
The normal relation between the anterior termi-
nation of the 1st and 2nd parietals, excluding the 18
taxa where it is absent or data was unavailable, is for
the 2nd to project slightly (fig. 37a). This occurs in
52.8 per cent (85) of the species. In 31.7 per cent (51
taxa) it is even with the 1st, while in 3.1 per cent (5) it
is slightly behind, and in 12.4 per cent (20) it is deeply
recessed. Recession of the 2nd parietal frequently is a
prelude to loss of the barrier. A small, deeply recessed
2nd parietal normally occurs in Nesodiscus taneae and
N. huaheinensis , only rarely in N. obolus, and is lost
in the other Nesodiscus species. Thirteen taxa of
Libera have a deeply recessed 2nd parietal, it is totally
lost in L. retunsa and L. tumuloides, while only in the
very small L, umbilicata and L. micrasoma are the
2nd parietals equal in size and length to the 1st. L.
gregaria has 2 equal parietals and occasionally a 3rd.
Other taxa with deep recession of the 2nd parietal
include Rhysoconcha, Opanara duplicidentata, Mau-
todontha maupiensis, and Taipidon petricola petri-
cola. All of these species have 3 to 5 parietal barriers.
The Opanara and Taipidon are the only members of
their genera that have 4 parietals. The "reduced 2nd"
could be an added barrier in these two species, while
the Rhysoconcha appear to be involved in secondary
size reduction (pp. 255-256) and thus the significance
of the deeply recessed 2nd parietal is uncertain.
TABLE XXV. - CORRELATION BETWEEN ANTERIOR DESCENSION OF
2ND PARIETAL BARRIER, DIAMETER, AND WHORL COUNT
IN SPECIES WITH 2 PARIETAL BARRIERS
Type of
descension
Sharply
Gradually
from middle
1/lt to 1/3 is
threadlike
3/8+ is
threadlike
Number
of taxa
15
10
13
23
X D
5.51±O.Uli
(1.86-8.146)
3.9010.31
(2.28-5.10)
14.16*0.55
(1.79-8.99)
U.72±0.25
(3.06-6.91)
X W
6.63±0.26
(U. 00-7. 675)
5.55±0.30
(U. 125-6. 950)
5.5U±0.2l4
(3.625-6.500)
5.73±0.19
(14.075-8. 050)
Mautodontha maupiensis belongs to a genus in which
many species have the basic 4 parietal compliment
reduced to only 1 or 2 and thus may represent an
incipient reduction series.
While no direct measurement of parietal barrier
width was feasible, the relative degree of expansion for
the microdenticulated area compared with the barrier
shaft could be observed and special modifications
noted. The data are summarized in Table XXVI. This
variation includes both size-correlated and straight
phyletic factors. The "beaded" structure (figs. 41a;
194d; Solem, 1973d, fig. 10) is characteristic of and
restricted to the anatomically isolated Thaumatodon-
TABLE XXVI. - CORRELATION BETWEEN DIAMETER
AND SUPERIOR STRUCTURE OF PARIETAL BARRIERS
Barrier:
Not expanded
Weakly expanded
Moderately expanded
Strongly expanded
Bifid
Beaded
Lateral extensions
XD
U.8U+0.30
(3.06-11.29)
U.Uo+0.19
(1.68-12.26)
3.H*±0.15
(1.86-U. 36)
3.11±0.28
(1.73-5. 5*0
(1.79-8.99)
3.1*2±0.20
(2.15-5.10)
It. 06
Number
of taxa
28
80
26
17
Zyzzyxdonta-Aaadonta-Priceconcha complex. Thau-
matodon multilamellata (Garrett) (fig. 192d, e) has
separate, evenly spaced "hooks" developed on the
denticles, but all the other species have this beaded
structure. Kondoconcha othnius is unique in having
accessory trace barriers mounted medially on each side
of both major parietals (fig. 108c, d), which otherwise
are only moderately expanded above. Formation of a
bifid upper parietal has occurred in three lineages, a
Hawaiian, an Austral Island, and a Gambler Island
group. The Hawaiian Cookeconcha nudus, C. thwingi,
C. henshawi, Endodonta binaria, E. concentrata, E.
lamellosa, E. marsupialis (fig. 167a), E. fricki (fig.
167g), and E. ekahanuiensis form one apparently
monophyletic assemblage. In these species the bifidity
occurs because of a slanted lower addition to the upper
parietal that may or may not be counterbalanced by a
slight upward deflection of the main lamellar blade.
The area between the two blades is partly filled in
with calcareous deposition, giving a concave contour to
the upper parietal. The Austral Island Minidonta
micraconica (fig. 65b, d, e) and M. gravacosta (fig.
65g) have the same basic type of bifidity, except that
the lower blade is inserted more directly on the lower
surface and there is no deposition between the two
blades. The angle at which the secondary blade is
PATTERNS OF MORPHOLOGICAL VARIATION
57
attached is more nearly perpendicular in the latter
species. The Mangarevan M. taravensis (fig. 71c) has
the 3rd parietal bifid, probably by fusion, while
Anceyodonta andersoni and A. alternata have the
upper bifid posteriorly. Rarely the 3rd parietal is bifid
in A. obesa. Bifidity of the upper parietal has thus
occurred among the smallest (Minidonta) and largest
(Endodonta) of the taxa, which is reflected in the
large standard errors of the mean (table XXVI). The
net effect of a bifid upper parietal is to widen the area
along the parietal wall that is effectively narrowed by
the barriers. In non-bifid species the vertical distance
between the 1st and 2nd parietal is "empty space" and
not narrowed. The other major variation occurs in
Rhysoconcha (figs. 108a, b; 112) whose barriers are
greatly distorted, probably as a result of secondary size
reduction (pp. 255-256).
The above special variations have been excluded
from analyzing the pattern of barrier expansion, since
although the effect of these changes is the same as
alterations in superior expansion, I could not equate
these exactly with the stages in simple superior
expansion. The latter were coded (table XXVI) as
strongly expanded (fig. 83), moderately expanded (fig.
70a), weakly expanded (fig. 69e), and not expanded
(fig. 144). The change from the moderately to weakly
to not expanded states clearly is size correlated. Larger
species have less superior expansion of the barriers
than smaller sized taxa. Partly this is directly size
correlated, but a large part of the "not expanded"
category correlates with size reduction of the barriers.
Of the 28 "not expanded" taxa, only the Marquesan
Taipidon semimarsupialis (fig. 143e) has fairly promi-
nent parietals. Yet these are reduced in size within the
context of the genus (compare T. analogica, fig. 143a,
d). The remaining taxa have the parietals reduced to
threadlike traces, low ridges, or split into many
threadlike traces. Often both the palatal and colu-
mellar barriers are lost or reduced greatly in number.
Strongly expanded barriers are characteristic of
the Minidonta- Anceyodonta complex from the Gam-
bier Islands, with two Minidonta, four Anceyodonta,
the monotypic Rikitea, and one Gambiodonta includ-
ed. Otherwise, there are Minidonta rotellina (Pease)
from Aitutaki, Cook Islands, four Rapan taxa (Rhyso-
concha variumbilicata and the Orangia cookei
complex), and Cookeconcha cookei (Cockerell) from
Oahu. The distinction between moderately expanded
and strongly expanded is not sharp, with the latter
condition usually indicating a bulbous expansion on
part of the barrier, while the moderately expanded
species tend more to have the entire microdenticulated
section of the barrier expanded. These taxa are
scattered more widely throughout the family, with 10
genera included.
Other noteworthy variations in the parietal bar-
riers are a tendency for barrier size reduction to
accompany splitting into numerous threadlike traces.
In the unique Minidonta extraria (fig. 71d, f) each
major parietal has several threadlike traces while
retaining the strongly expanded denticulated sections.
Species such as Opanara megomphala (fig. 106a, c),
Australdonta radiella (Pfeiffer) (fig. 132a, c), Taipidon
centadentata (fig. 144), Planudonta intermedia (fig.
149c), and Gambiodonta tumida (fig. 188a-b), show
partial to near-total reduction to threadlike traces.
Columellar barriers
The larger or only columellar barrier may be (fig.
37b) a high C-shaped or blade-like structure extending
from well inside the aperture to or near the lip edge.
Sometimes (for example, fig. 86d, e) it may be partly
to nearly buried by a heavy columellar callus in adult
and gerontic individuals. In other taxa it is reduced to
a thread-like trace (fig. 82a) and/or is very deeply
recessed within the aperture (fig. 203b). In 61 taxa the
columellar barrier is absent. The barrier, when present,
may be parallel to the plane of coiling (fig. 123d),
slanting downward from the coiling plane (fig. 86c), or
(in extreme cases) deflected onto the basal lip of the
shell (fig. 104).
In a few taxa there routinely is more than 1
columellar barrier. Thaumatodon euaensis, T. multila-
mellata, both subspecies of Aaadonta fuscozonata,
Anceyodonta sexlamellata, and Planudonta ma-
tauuana have 2 columellar barriers. Planudonta
intermedia, both races of Opanara megomphala and
Taipidon centadentata, have many threadlike barriers.
They, plus P. matauuna, represent taxa in which there
has been splitting and reduction of the parietal and
palatal barriers. The Thaumatodon, Aaadonta, and
Anceyodonta are taxa with fully developed large
barriers and thus show a different pattern of barrier
addition. Thaumatodon hystricelloides and T. va-
vauensis have either 1 or 2 barriers, and thus can be
viewed as potentially in the process of adding the
second barrier. The Thaumatodon-Aaadonta-Zyzzyx-
donta complex thus has six of 18 taxa with at least a
strong tendency toward 2 columellar barriers, while
only one taxon of the other genera, Anceyodonta
sexlamellata (Pfeiffer), has 2 columellar barriers by
other than a barrier size reduction process. Species in
which the columellar barrier is infrequently absent are
discussed in the text individually.
The pattern of columellar barrier loss is docu-
mented in Table XXVII. Such speciose taxa as
Anceyodonta, Endodonta, Taipidon, Gambiodonta,
Thaumatodon, and the Rapan genera show only a few
species or are not listed, since these taxa retain
prominent columellar dentition. In contrast, such taxa
as Nesodiscus, Nesophila, Rikitea, Pseudolibera, and
Planudonta, represent cases of great size reduction,
splitting, and/or loss of barriers from the aperture. In
these taxa many or virtually all of the species lack a
columellar barrier. Australdonta has only one species,
A. raivavaeana, that retains a weak, threadlike ridge
in three-quarters of the examples, while all other
Australdonta have no barrier on the columellar wall.
It may be, however, that the extra palatal of
58
SOLEM: ENDODONTOID LAND SNAILS
TABLE XXVII. - LOSS OF COLUMELLAR BARRIER
Columellar barrier
Absent Deeply recessed
Genus Total taxa
Minidonta
15
Mautodontha
IT
Cookeconcha
16
Kleokyphus
2
Opanara
12
Rhysoconcha
2
Ruatara
1|
Australdonta
12
Taipidon
11
Planudonta
1*
Rikitea
1
Nesodiscus
10
Nesophila
2
Pseudolibera
1
Libera
19
Aaadonta
9
9
12
1
11
1
2
1
10
2
1
6
1
Australdonta may be a descended columellar. In
Mautodontha, Cookeconcha, Libera, Minidonta, and
Aaadonta up to two-thirds of the species lack a
columellar barrier. If deep recession of the barrier is
viewed as a prelude to its loss, then the phyletic
linkage of barrier loss becomes even stronger (table
XXVII).
Barrier size and relative position with respect to
the lip edge are shown in Table XXVIII. The general
agreement between the two variables, high lamella
reaching near to lip edge and low threads or ridges
deeply to partly recessed is obvious. The position of
the barrier in relation to the lip edge is variable at a
low taxonomic level, however. The subspecies of
Orangia cookei (fig. 123a, c, d), for example, are
identifiable by the degree of barrier recession alone.
There also is an obvious relationship between barrier
position relative to the plane of coiling and how nearly
it approaches the lip edge (table XXIX). A change in
barrier anterior growth generally involves just the tip
at the callus area. The one species in which the barrier
is both deeply recessed and deflected onto the basal
margin, Opanara fosbergi (fig. 107c), is extremely
compressed above and below, with the result that part
of the columellar wall has, in effect, been moved onto
the basal margin. The other species involving
deflection show two distinct patterns. In Ruatara
koarana (fig. 113b) and the three subspecies of
Opanara areaensis (fig. 104), the barrier begins in
normal columellar position, with terminal growth at
adulthood deflecting the anterior portion downward.
In four Gambier Island taxa, Minidonta taravensis
(fig. 71a, c), Anceyodonta labiosa (fig. 87d, e), A.
difficilis (fig. 83a), and A. soror (fig. 83e), the
columellar barrier is extremely high and has rotated
downward through a 90° arc onto the basal lip, with a
slight inward twist at the anterior end. Thus deflection
of the columellar barrier onto the basal margin has
been accomplished in at least three different ways. A
reverse variation is seen in Mautodontha subtilis
(Garrett), where 25 per cent of the specimens have the
1st palatal shifted up onto the columellar wall.
Presence or absence and actual height of the
columellar barrier are not directly size correlated
(tables XXX, XXXI). The mean whorl count (table
XXX) of species with and without barriers is virtually
identical, but the diameter is significantly different
("t" is 2.5014 with 177 df). This conflicting pattern
partly is a phyletic artifact. Most Libera, all Gambio-
TABLE XXVIII. - CORRELATION BETWEEN COLUMELLAR BARRIER HEIGHT
AND POSITIONAL RELATION TO LIP EDGE
Barrier
position
Lip edge
Midway
across
callus
Top of
callus
Deeply
recessed
Totals
low
rounded
thread
0
low
ridge
6 9
3 8
7 10
low
lamella
16
30
3
3
_2
13
Barrier height
high lamella,
gradual descension
17
12
5
_6
UO
high lamella,
sharp descension
h
1
_0_
19
Totals
39
3U
20
25.
118
PATTERNS OF MORPHOLOGICAL VARIATION
TABLE XXIX. - COLUMELLAR BARRIER POSITION AND RECESSION
Recession: Position
barrier
reaches- Parallel Slanting down Deflected onto
basal margin
Lip edge
Midway
across
callus
Top of
callus
Deeply
recessed
18
19
15
22
lit
lit
5
2
donta, and all Endodonta, which have high whorl
counts and have, or tend toward, brood chamber
growth patterns, have proportionately low diameters
relative to their whorl counts, since the growth vector
has shifted (pp. 21-29). They retain prominent denti-
tion. In contrast, taxa at or near the Nesodiscus level
of specialization (p. 113), such as Nesodiscus,
Planudonta, Nesophila, and Rikitea, combine high
whorl count, wide umbilici, and reduced apertural
barriers. The greater diameter of those taxa without
columellar barriers reflects a difference in both growth
vectors and the phyletic tendency toward general
tooth reduction. Similarly (table XXX) there are no
correlations between position of the columellar barrier
relative to the lip edge and shell size.
Shell size and columellar barrier height (table
XXXI) show only slight size correlation. Those taxa
with either a low lamellar barrier, or a high lamellar
barrier that descends gradually, average larger in
diameter and whorl count than those with other
barrier heights, but the differences are only marginally
statistically significant and the overlap of ranges is
extensive. Both categories include many brood-cham-
ber taxa, with their increased whorl count. It is
probable that the elongation of the lamellar barrier in
these taxa is a simple correlative of the extra growth.
In summary, the columellar barriers show little
direct size-correlated variation, but rather indicate
phyletic linkages and patterns of variation rather
closely. States of alteration in barrier position and size
TABLE XXX. - SHELL SIZE AND COLUMELLAR BARRIER POSITION
arner :
Present
Barrier position:
Lip edge
Midway
across
callus
Top of
callus
Deeply
recessed
Number
of taxa
118
61
39
25
3.91+0.15
(1.68-12.26)
14.58*0.22
(2.59-11.29)
3.78±0.29
(1.79-12.26)
3.70*0.28
(1.68-8.99)
it. 16+0.35
(1.73-8.1.6)
14.23+0.32
(1.97-7.30)
Whorl count
5.7lt±0.08
(3 5/8-8)
5.67*0.12
(3 5/8-8)
5.58+0.11
(3 5/8-7 3/8)
5. 59*0. 13
(fc-7 1/8)
6. 01 ±0.22
(1- 1/2-7 5/8)
5. 96 ±0.17
(U 7/8-8)
can be demonstrated to be derived in different ways
and thus are convergent in nature.
Palatal barriers
The palatal barriers (fig. 37c), have a typical
pattern of change in shape, becoming progressively
longer and lower from basal lip to upper palatal wall.
Frequently the barriers will be well developed and
prominent on the lower palatal wall, but with only a
single reduced ridge present above the periphery, as,
for example, in Taipidon (fig. 145a, c), Libera (fig.
184b, e), Thaumatodon (fig. 196b, e), and Aaadonta
(fig. 206b, e). This is most common in taxa with angled
or keeled peripheries. Equally common is the presence
of supraperipheral traces (fig. 36), with or without a
TABLE XXXI. - SHELL SIZE AND COLUMELLAR BARRIER HEIGHT
Barrier height
Low thread
Low ridge
Low lamella
High lamella,
gradual descension
High lamella,
sharp descension
Number
of taxa Shell diameter
16
3.1*5±0.23
Whorl count
5.38+0.114
(lt-6 1A)
30 3.1tl±0.27 5.58+0.16
(1.68-7.60) (It 1/8-7 5/8)
13 lt.3l»±0.55 6.15±0.29
(2.33-7.30) (It 7/8-8)
ItO lt.6l±0.30 6.05+0.11
(2.58-12.26) (It 3A-7 1A)
19
3.36+0.2lt
(1.79-5.06)
5.36+0.18
(3 5/8-7)
major barrier near the parietal-palatal margin (figs. 87,
88, 89, 140a, c). The absence or lower profile of palatal
barriers in this upper sector of the aperture correlates
with the tendency for the 1st parietal, which
frequently is the highest of the parietal barriers, to lie
opposite this region and protrude into the area. The
low traces sitting opposite the largest parietal also
preserve a space function, since the widest gap between
opposing barriers occurs in this region. This space
probably permits the buccal mass and foot to be
withdrawn past the barriers through this open chan-
nel.
Height variation in the palatal barriers partly
correlates with the relative sizes of the lower parietal
and columellar barriers. When these are small, as in
Figure 143d, the 1st palatal will be higher than the
2nd. In taxa where the columellar (fig. 162b) and/or
the lower parietal (fig. 71c) are very large, the 1st
palatal will be slightly to significantly reduced in
height. Similarly, where the 1st parietal is very large,
as in Minidonta taravensis (fig. 71a, c), the palatal
barrier lying on the opposite wall will be markedly
reduced in prominence. Because this pattern differs
quite widely within genera and is of complex origin, no
satisfactory criteria for comparing relative palatal
barrier height between species were formulated. Dis-
cussions of major variations in barrier shape, position
relative to the lip edge, superior expansion, and
correlatives of barrier loss and reduction precede
consideration of correlations with parietal barrier
features.
60
SOLEM: ENDODONTOID LAND SNAILS
Barrier
shape
TABLE XXXII. - PALATAL BARRIER SHAPE AND LENGTH CORRELATIONS
Barrier Length
Under To line
1/8 whorl 1/8 whorl 3/l6 whorl 1/U whorl of vision
Beyond line
of vision
Crescentic
Blade-like,
sharp descension
Blade-like,
gradual descension
Low ridges
Threadlike
3
2
1
58
5
1
38
15
Barrier shape is relatively constant, with depar-
tures from the basic form (fig. 37c) correlated more
with barrier length than any other factor (table
XXXII). Shortening of the barrier may result in a
crescentic form or one with much sharper anterior
descension. Size reduction to a threadlike or low ridge
status can correlate with either very short or very long
barriers. All these changes may signal a tendency
toward barrier loss, since the only taxa with crescentic
palatals are three Cookeconcha and the two dentate
races of Ruatara oparica. A high proportion of
Cookeconcha and Ruatara oparica reductidenta have
reduced or no palatals (table XXXVII), and the
concentration of change to a crescentic shape in these
taxa seems significant.
Position of the palatal barriers relative to the lip
edge is far more variable than the position of the
parietal barriers. The latter, without exception, extend
essentially to the plane of the lip edge or slightly
beyond, depending on the parietal callus protrusion. In
contrast, the palatal barriers can extend to the lip edge
(fig. 204a, c) or lie so deeply recessed that they are
barely visible by tilting the aperture (fig. 189a). The
pattern of this change is size correlated (tables
TABLE XXXIII. - PALATAL BARRIKR RECESSION AND SIZE CORRELATIONS
Palatal
barrier
recession
Lip e :
Slightly
recessed
Moderately
recessed
Deeply
recessed
Barely
visible
Absent
Number
of taxa
39
•
Diameter
• . l .
. PT-lt. N
. • . I
. -I .
Whorl count
5.1)0+0.11
C<-7 1/2)
U-6 3/0)
. n.12
XXXIII, XXXIV). Taxa with the palatal barriers at
the lip edge or only slightly recessed (table XXXIII)
do not differ significantly in size from each other ("t"
= 1.5772 with 89 df) and their whorl count is identical.
There are highly significant size and whorl count
differences in going from "slightly" to "moderately"
and then to "deeply" recessed palatal barriers. The
changes in diameter, respectively, have "t" 's of 4.1558
with 78 df and 2.2751 with 56 df. The change in whorl
count has, respectively, "t" 's of 2.1191 with 77 df and
3.6609 with 55 df. Since the change from "deeply
recessed" to "barely visible" is only accentuating a
basic trend, the lack of size change is expected. The
slightly smaller size of taxa in which the barriers are
lost reflects the diverse number of taxa in which this
phenomenon has occurred (p. 62).
Major recession of the palatal barriers is corre-
lated with brood chamber formation and increased
whorl count more than any other factor (table
XXXIV). The clustering of these states in Nesodiscus,
Pseudolibera, Gambiodonta, and Libera is obvious.
Orangia has the highest mean whorl count of the
Rapan taxa; and Planudonta represents an increase in
whorl count over Taipidon, except for the brood
chamber species, T. semimarsupialis. This correlation
of deep recession with increased whorl count requires
more analysis than available data permits. I have no
information as to whether the normal pattern is for
the deep recession to result from a sudden cessation of
barrier growth followed by continued lip edge accret-
ion; a slowing of barrier growth at some stage in
development; or a gradual development throughout
ontogeny. Examination of extensive growth series
would permit at least partial solution of this problem,
but the necessary material was not available for study.
Young Gambiodonta grandis (fig. 189e) have the
palatals only slightly recessed, but in adults (fig. 189a)
they are barely visible. Since that species is the only
Gambiodonta with deep recession, this is only sugges-
tive of one situation.
The deeper recession of palatal barriers than
parietals probably has direct functional significance.
PATTERNS OF MORPHOLOGICAL VARIATION
TABLE XXXIV. - PHYLETIC CORRELATIONS OF PALATAL BARRIER RECESSION
61
Cookeconcha
Endodonta
Nesophila
Minidonta
Mautodontha
Anceyodonta_
Kleokyphus
Rhysoconcha
Opanara
Kondoconcha ;
Ruatara
Orangia
Taipidon
Planudonta
Thaumatodon
Aaadonta
Zyzzyxdonta
Australdonta
Nesodiscus
Gambiodonta
Libera
lip edge
1
5
3
6
I
2
It
1
7
3
1
slightly
recessed
moderately
recessed
deeply
recessed
It
1
3
3
5
7
2
1
6
it
5
1
1
7
1
1
2
It
1
It
2
1
2
1
6
Rikitea
Pseudolibera
The basic microdenticulations on the upper barrier
edge could be used as the gripping surfaces for mantle
edge extension after deep retraction of the animal.
Columellar and parietal surfaces would be used more
extensively in this than the palatal wall, which is
further from the shell axis. Hence retention of the
parietal barriers to the lip edge presumably would
continue to serve a significant function even after their
apertural narrowing function had lessened. In
contrast, there would be little selective value for
extending the palatal barriers to the lip edge.
Palatal barrier expansion is partly size correlated
(table XXXV), and parallels, but does not exactly
follow the degree of parietal barrier expansion (table
XXXVI). As in the parietal barrier expansion, a weak
or slight expansion of the barriers is normal (table
XXXVI). More than half of the taxa show this
generalized condition. The proportion showing "typi-
cal" palatal barrier expansion is greater, probably since
barely
visible absent
1
1
3
1
1
1
It
17
3
2
1
1
1
the palatal barriers are lost in so many taxa. Only one
species, Endodonta binaria (Pfeiffer), has the palatal
barriers bifid. All of the 12 taxa in which the palatal
barriers are not expanded represent forms with great
size reduction of the barriers. Orangia sporadica (fig.
123f), the three Planudonta that retain palatal
barriers, the two subspecies of Ruatara oparica with
palatal barriers, three of the four "Group III"
TABLE XXXV. - SIZE CORRELATION WITH PALATAL BARRIER EXPANSION
Number
Barrier:
of taxa
Diameter
Whorl count
Not
expanded
12
Il.00t0.l8
(2.98-U.98)
5.55±0.18
(U lA-6 3/8)
Moderately
expanded
20
3.35±0.27
(1.97-6.60)
5.51±0.18
(1* 1A-8)
Strongly
expanded
15
2.65±0.20
5.16+0.17
(1.73-5.06)
(3 5/8-6 3/8)
62
SOLEM: ENDODONTOID LAND SNAILS
TABLE XXXVI. - PATTERNS OF BARRIER EXPANSION
State:
No data
Absent
Not expanded
Weakly expanded
Moderately expanded
Strongly expande 1
Bifid
Lateral accessory
Beaded expansion
Number of taxa
Parietal Palatal
1
28
80
26
Ik
11
1
17
1
22
12
91
20
15
1
0
17
Cookeconcha, Taipidon centadentata, and both sub-
species of Opanara megomphala have obvious and
extensive barrier size reduction. In mean size and
whorl count they are average for the family (table
XXXV), but are obviously and significantly larger
than those taxa with moderately or strongly expanded
palatal barriers. Strongly expanded palatal barriers are
found in the smaller Hawaiian Cookeconcha and
Endodonta; Mangarevan Minidonta and Anceyo-
donta; Taipidon petricola petricola (the smallest sized
taxon in the genus); and both species of Rhysoconcha,
which are secondarily reduced in size (pp. 255-256).
These species are distinctly smaller in size and slightly
lower in whorl count (table XXXV), but not all small
species, by any means, have strong palatal barrier
expansion. Moderate expansion of the palatal barriers
is spread among 20 species belonging to 11 genera.
These are intermediate in size, but have an average
whorl count.
Loss of the palatal barriers (table XXXVII) has
occurred in 22 (11.3 per cent) of the taxa, compared
with total loss of the parietal barriers only in
Nesodiscus fabrefactus. The palatal barrier loss is
found in two monotypic genera, Pseudolibera and
Rikitea; both species that I have examined of the
. /.XT/II. - REDUCTION AtlD LOSS OF PALATAL BARRIERS
: 1 1 .:• -• ..;
:.:.!-• ionta
Pseudoi 1 : era
"lumber
of taxa
1?
IT
l;
14
Li
11
.
1
.1
Barrier low ridge
or threadlike
1
0
2
2
0
1
3
•
1
1
Barrier lost
0
14
6
o
L.
1
0
3
0
1
1
2
0
1
1
Hawaiian Nesophila; Planudonta concava, which is
the largest of the four species in that genus; only one
subspecies, Ruatara oparica reductidenta, of the
Rapan radiation; the two largest Nesodiscus species,
N. magnificus and TV. fabrefactus; Libera retunsa
generally (9 of 11 specimens) lacks palatal denti-
tion; and several taxa in Cookeconcha, Mautodontha,
and Australdonta lack the barriers. The six Cooke-
concha (C. decussatuhis, C. jugosus, C. thaanumi, C.
paucicostatus, C. lanaiensis, and C. hystrix) have a
larger mean shell diameter (4. 64 ±0.44) than those
with palatal barriers (3.45 ± 0.40). The difference is
significant ("t" = 1.914 with 13 df) at the 5 per cent
level. The several Mautodontha (M. aoraiensis, M.
consimilis, M. acuticosta, and M. unilamellata) also
show size reduction of the parietal barriers, but do not
differ in size from those with well-developed barriers.
Similarly, the three Australdonta (A. ectopia and both
subspecies of A. radiella) do not differ significantly in
size from the other species in the genus.
Of the above taxa, the Pseudolibera, Nesodiscus,
Nesophila, Planudonta, and Cookeconcha represent
either large-sized species in general or the largest in
their lineages. The correlation is not exclusively with
large size, since most Libera, all Gambiodonta, and
the Hawaiian Endodonta retain very large and
prominent palatal barriers. In the case of the Ha-
waiian taxa, a habitat shift may have more to do with
the barrier loss than size factors. Cookeconcha has
been found on stumps and logs (Pilsbry and Vanatta,
1906, p. 783) or on mossy tree trunks (personal
observation), while Endodonta is known from under
twigs and dead leaves (Pilsbry and Vanatta, 1906, p.
783) or talus slopes (Cooke, 1928, p. 14). Species of
Endodonta mostly are much larger than species of
Cookeconcha, but by remaining in the ground strata,
Endodonta may have reason for retention of large
barriers. If the primary predators were ground strata
hunters, then Cookeconcha's shift in habitat could
significantly reduce the selective value of the barriers.
The reasons for palatal barrier loss in the
Mautodontha species is unknown. Only M. aoraiensis
(figs. 74e, f) retains prominent parietals, while in the
other three (figs. 78b-g) the parietals also are greatly
reduced in size. Australdonta radiella (fig. 132) has
the parietals reduced to threadlike traces, but shows
no unusual shape or sculpture features, while A.
ectopia (fig. 137e) has only a single parietal trace
remaining.
Reduction of the palatal barrier to a low ridge or
threadlike state can be viewed as a prelude to barrier
loss. Tallying reduction and loss together (table
XXXVII) emphasizes that lineage is more important
than size factors, since the reductions in Cookeconcha,
Taipidon, Planudonta, and Nesodiscus account for
62.5 per cent of all palatal barrier size reductions.
When combined, the loss or great reduction of palatal
barriers is concentrated in Mautodontha, Cooke-
concha, Australdonta, Planudonta, Nesodiscus, and
PATTERNS OF MORPHOLOGICAL VARIATION
63
Nesophila, with 26 (68.4 per cent) of 38 taxa clustered
in these six genera.
Parietal and palatal barrier trace and expansion
correlations
Tables XXIII, XXXVI, and XXXVIII give some
indications of semi-independence in barrier character-
istics on the two main apertural walls. The presence of
palatal traces (table XXIII) does not correlate, in
TABLE XXXVIII. - CORRELATION OF UNUSUAL PALATAL BARRIER
EXPANSION WITH PARIETAL BARRIER EXPANSION
Parietal
expansion
not
weakly
moderately
strongly
bifid
not
5
5
2
Palatal expansion
moderately strongly
most cases, with similar parietal traces, and only 15 of
24 genera have such traces. Only palatal traces occur
in the Hawaiian lineage, the Thaumatodon complex of
genera tends to have both, while members of the
Minidonta - Mautodontha - Anceyodonta - Gambio-
donta complex have both in varying proportions. If
allowance is made for the much greater loss of palatal
barriers (table XXXVII), then the more conservative
pattern of palatal barrier expansion is obvious. Bifid
parietals will, in effect, be broadly expanded. When the
patterns of parietal barrier expansion are correlated
with unusual palatal barrier expansions (table
XXXVIII), the departures from a "one-to-one" rela-
tionship are obvious.
Further comparisons of palatal and parietal
barriers are deferred until after discussion of barrier
growth and microdenticulation patterns.
Barrier growth
The apertural barriers in most species retain their
same position relative to the aperture from hatching
through old age. There thus has to be a pattern of
incremental anterior growth and posterior resorption
coordinated with increased shell size. The pattern of
this growth can be deduced through scanning electron
microscope studies of anterior deposition and posterior
resorption areas. Opanara areaensis areaensis (fig. 39)
can serve as an example. It has high profile sculpture
on the shell surface, thus requiring change in the
normal pattern of parietal callus and wall deposition
(fig. 39b). In smooth-shelled taxa, such as zonitoids,
the parietal callus can be deposited directly onto the
previous shell layer. Probably at most there is
dissolution of the periostracum to permit better
bonding of the calcareous shell layers. In Opanara
there is obvious dissolution not only of the overlying
periostracum, but also a significant part of the
underlying calcareous ridge structure prior to deposi-
tion of the initial thin callus layer (see lower left of fig.
39b). Such adsorption is not total (fig. 39c), since the
remnants of the radial ribs are clearly visible as
contours in the parietal callus between the 1st and 2nd
parietal barriers. The increase in rib visibility from
right to left in Figure 39c is only partly an artifact of
increasing curvature. It mainly comes from increasing
thickness in the parietal callus which tends to "even
out" the surface and gradually eliminate the surface
irregularities that reflect rib position on the previous
whorl. This is most easily explained by assuming that
as the callus is extended anteriorly as a single layer
(fig. 39b), a similar thin layer is deposited over the
inner surface of the callus and barriers at least up to
the point at which the superior microdenticulations
occur. Evidence for such a pattern of layering is found
by examining the posterior margin of the barriers (figs.
40, 41). In Thaumatodon hystricelloides, which has a
very thick palatal callus, the multi-layered nature of
the callus is evident at the resorption surface (left of
fig. 41a). Although less prominent, the same layering
can be seen in Opanara areaensis (Solem, 1973b,
lower left of fig. 10). Deposition and resorption of the
denticulated portions of the barriers is a more complex
matter. While the anterior threadlike and non-
denticulated barrier surfaces apparently are added to
in multiple increments, the denticulated portion
remains stable in height and has a very complex
surface in the Endodontidae. The lower portion of
each barrier shows layering on the resorption surface
(fig. 40) just below the denticulated bulge, but the
latter shows no traces of layering at much higher
magnification. Below the obviously layered section is a
slanted resorption facies with grooves etched into the
barrier. This suggested that the mantle tissue secretes
a weak acid that effectively dissolves the barrier and
callus. Very probably the mantle gland extensions
onto the pallial roof (figs. 163e; 171e, MG) control
both aspects of growth. The lack of layering in the
denticulated bulge suggests that this is deposited as a
single "cap" around the multi-layered barrier and then
not further involved in the process of callus and
barrier formation until resorption.
The pattern is quite different in the Charopidae,
where the denticulated surfaces can be seen on the
anterior slope of the barrier (Solem, 1973b, fig. 17) and
thus layered deposition is possible. Even in a species
with comparably shaped barriers, such as the St.
Helena Island Helenoconcha, the denticulated surfaces
are deposited in successive layers (Solem, in press A).
The latter pattern probably reflects the lowered whorl
count and thus more rapid increase in whorl cross-
section found in the Charopidae as opposed to the
Endodontidae. In the latter there would be less rapid
change in barrier height needed to maintain the same
absolute degree of apertural narrowing and thus single
denticulated layer formation with gradual anterior
increment would be effective. In the Charopidae,
where more rapid barrier height increment per unit of
whorl growth would be required, the multiple layer
pattern of denticulation would be effective and
efficient.
64
SOLEM: ENDODONTOID LAND SNAILS
FIG. 40. Palatal barrier resorption surface in Thaumatodon
spirrhymatum. 780 x.
While the layered nature of growth in the barriers
has been established, there is no direct evidence of
growth and resorption sequence. Simple observation
shows that the length of the barriers varies slightly
within a population, generally within less than a
sixteenth of a whorl. The difference is in the whole row
of barriers. Except for teratological examples, the
entire row will be added to or resorbed equally. In
juveniles there are clear differences in the distance
from lip edge to anterior barrier termination, suggest-
ing that there is no one-to-one correlation in shell
increment and barrier increment. Putting these obser-
vations together suggests a simple pattern of
postembryonic barrier growth and resorption, in which
there is first posterior resorption and barrier shorten-
ing. This is followed by subsequent anterior additions
to the callus and barriers. The exact correlation with
shell edge increments is unknown. Such a sequence
would be efficient in terms of energy budget, since
calcium resorbed from the barrier posterior could be
deposited at the anterior end. The alternate sequence
of anterior addition followed by posterior resorption
would require an extra energy load on the snail. In
addition, extra calcium would have to be accumulated
from the environment to support the anterior addition,
then calcium resorbed from the posterior would have
to be stored until needed for the next growth
increment. This would be highly inefficient. Whether
there is linkage or not between parietal and palatal
growth changes is unknown.
The above data on growth do serve to explain the
layered nature of the barriers and provide an
explanation for the variation observed in barrier
length. Because the length generally had to be judged
by obtuse-angled viewing into the aperture, exact
length measurements could not be obtained. The cited
differences of barrier length must be treated as
relatively crude estimates. In a few taxa, such as
Australdonta degagei, however, the barriers were
clearly visible through the palatal wall and their
FIG. 41. Palatal barrier sculpture in Thaumatodon hys-
tricelloides (Mousson). Station 19, Lake Lanuto'o, 2,500 ft., Upolu,
Samoa. FMNH 153452: a, fractured edge of palatal callus and two
palatal lamellae with single beads on each, 300x, note even nature
of layering beneath palatals; b, top of single palatal bead at 3,000 x ;
c. individual barbs at 10,OOOX .
PATTERNS OF MORPHOLOGICAL VARIATION
65
length could be measured directly. Barriers of adult A.
degagei showed about a 10 per cent range in barrier
length. In juvenile specimens this reached an observed
maximum of 25 per cent although most variations
were in the 15-20 per cent range.
Mi croden ti cula tions
Under optical examination, the upper, posterior
edges of the barriers are seen to have minute
"serrations." Under the scanning electron microscope,
these are seen to consist of elongately triangular
microdenticles, generally sharp pointed (fig. 39d, e),
but sometimes blunt tipped (fig. 41b). All of these
point in the same direction, toward the apertural
opening. Elsewhere (Solem, 1972c) I have discussed the
possible original function of such microstructures and
their origin from micropustulations. The latter are
visible on the callus of Opanara areaensis (figs. 39c,
d). From a microgripping surface useful in extending
the retracted snail, more sophisticated and sharper
microdenticles provided added protection against
arthropod predation. The basic form and orientation of
these denticles are the same throughout the Endodon-
tidae. This contrasts with the Charopidae (Solem,
1973b), where the denticles are of many types, leading
me to suggest that barriers originated many different
times in the Charopidae, but that the extant Endodon-
tidae share a common ancestor in which micro-
denticulated barriers were present.
Within the Endodontidae, there are relatively
simple patterns of denticle variation. In the vast
majority of taxa, they are evenly distributed along the
upper expanded edge of the major barriers, but
absent from the lower and/or non-expanded anterior
sections. The microdenticulations do not occur on the
callus trough or threadlike portions of the barrier, but
are replaced by the micropustulations. In four genera,
Thaumatodon, Zyzzyxdonta, Priceconcha, and Aa-
adonta, the barrier shape is altered. Superior ex-
pansion is restricted to a series of relatively widely
(Thaumatodon spirrhymatum, Solem, 1973d, fig. 10) to
quite closely spaced (T. hystricelloides, fig. 194d, e)
"beads." These beads may be simple swellings (fig. 41a)
or variously laterally twisted (fig. 194d). The number
of such beads depends upon both their spacing and the
total barrier length. In one species, T. multilamellata
(Garrett), the barriers are topped with recurved hooks
(fig. 192d) or simple vertical points (fig. 192e).
Another variation has been observed in the larger
Endodontidae from Hawaii. Microdenticulations in
both Endodonta and Cookeconcha (fig. 42) may be
blunt tipped or even truncated (fig. 42f) on top of the
barrier, although retaining the basic triangular form
on the sides of the expanded portion (fig. 42a, b, e).
They thus have the basic form of the microdenticula:
tions found in the Charopidae (Solem, 1973b, figs. 15,
16, 19, 21, 22) on the barrier top, but the pattern of
attachment (fig. 42a) shows that these are derived
from the basic endodontid pattern. All of those
specimens agree in having the uniform pattern of
microdenticulations. This suggests quite strongly that
the triangular points are the generalized condition in
this group. Even when the barrier expansion is
changed to "beaded" patterning, the character of the
microdenticulations is constant.
Barrier numbers and length
Variation in the number of parietal and palatal
barriers shows a combination of both size and phyletic
factors. Previously (pp. 52-58, 62-63). I have discussed
the pattern of loss and size reduction in these barriers.
Although generally there is a normal number of
barriers for all specimens of a given species, a
substantial number of taxa (39 of 179) show variation
in numbers of parietal (table XXXIX) and/or palatal
(table XL) barriers. In a few cases, the material
available permitted study of such variations between
populations of the same species. In Ruatara oparica
(fig. 115) there are geographic differences in the barrier
number changes. In Anceyodonta hamyana (table
LXXIII) the proportions fluctuate widely between
populations, while in Opanara bitridentata (table
LXXVIII) the limited data suggests a more consistent
variation pattern. Species of Australdonta (fig. 126)
show a variety of patterns.
The percentages listed in Tables XXXIX and XL
are based on a few to many specimens and/or
populations. Their reliability as being truly indicative
of the overall pattern in a species is low, but they do
suggest the variety of experimentation that exists and
hint at its nature. Percentages in taxa such as
TABLE XXXIX. - PERCENTAGE DISTRIBUTION OF PARIETAL BARRIER NUMBERS
Number of parietal barriers
Species
Mautodontha daedalea
?4. punctiperforata
Nl. parvidens
M^ rarotonfiensis
^. consinilis
'A_. acuticosta
Anceyodonta hamyana
A_. densicostata
/U labiosa
Opanara bitridentata
0_. a_. areaensis
Hhysoconcha atanuiensis
Huatara o_. oparica
R_. p_. reductidenta
Australdonta degaRei
A_. pseudplanulata
A_. tapina
A_. yoshii
A_. raivavaeana
Taipidon fragi la
^_. varidentata
T\ narquesana
T_. voapoensis
T_. petricola decora
Thaumatodon euaensis
1
2
3
It
67.7
32.3
71.1.
28.6
92.9
7.1
36.1.
63.6
9.1
90.1
23.li
76.1.
1.5.9
5">.l
15.0
85.0
36.1*
63.6
61.8
38.2
93.7
6.3
98.0
2.0
21.1
71.0
7.9
1.3
8.2
77.7
11.14
75.0
21.. 3
87.5
12.5
28.6
71.1*
90.9
9.1
73.2
22.1
60.0
1.0.0
75.0
25.0
25.0
75.0
25.0
75.0
15.0
85.0
38.1
61.9
1.3
FIG. 42. Palatal barrier sculpture in Hawaiian Endodontidae: a-d, Endodonta fricki (Pfeiffer). Waianae Mts., Oahu, Hawaii. BPBM 128063.
a, lateral view of 2nd palatal at 2,250 X; ft, top view of 2nd palatal at ll.OOOx; c, view from aperture of 2nd palatal lamellar sculpture at
2.750X ; d. same at 6.800X ; e-f, Coohecimchti nudus (Ancey). Kaiwicki, 2,500 ft. elevation, Hilo, Hawaii. FMNH 90319. e, top view of 2nd palatal
at l.OOOx ; f, same at 5,000 x . Photographs courtesy of Engis Equipment Company, Morton Grove, Illinois.
66
PATTERNS OF MORPHOLOGICAL VARIATION
TABLE XL. - PERCENTAGE DISTRIBUTION OF PALATAL BARRIER NUMBERS
67
Species
Mautodontha parvidens
M. rarotongensis
M. boraborensis
Opanara bitridentata
Rhysoconcha atanuiensis
R_. variumbilicata
Ruatara p_. oparica
R_. o_. normal is
Orangia sporadica
Australdonta degagei
A. pseudplanulata
Taipidon woapoensis
Libera b_. bursatella
L_. b_. orofenensis
L_. spur i a
L_. garrettiana
L_. heynemanni
L_. incognata
L_. jacquinoti
L_. subcavernula
L. tumuloides
Number of palatal barriers
123
5.1
6.3
Thaumatodon multilamellata
Australdonta degagei, Ruatara, Rhysoconcha, and
Libera bursatella are based on quite significant
specimen numbers. The low frequency deviants pre-
sumably thus reflect rare mutants or developmental
accidents. Other situations, as in the Australdonta,
hint at classic Mendelian dominance as the underlying
basis of variation. In discussing the correlatives of
barrier numbers, the varying extent of departures from
a uniform number presented practical difficulties.
Species were classed as having significantly variable
barrier counts only if one-third or more departed from
the standard number. Otherwise the species is grouped
with those taxa having the predominant character
state condition. While this underemphasizes the total
extent of variation, it does facilitate making
comparisons.
Most genera have a clear majority or nearly all
species showing a constant number of parietal barriers
(see table XLI). Only in Mautodontha, Anceyodonta,
66.7
7.0
33.3
5.3
5.1
25.0
89.8
62. U
3.2
7-9
19.2
25.0
12.0
6.3
9-7
k.6
86.7
11.8
3.8
It
86.0
88.2
78.1
86.3
73.6
82.0
3.5
75.0
88.0
87.1
95^
13.3
23.5
96.2
5
7-0
11.8
15.1
98.0
96.0
13.0
93.6
9^.8
95-3
5.2
6.1
2.0
U.O
5.0
66.7 33.3
Australdonta, and Taipidon are there massive ex-
perimentations in barrier numbers. Genera such as
Minidonta, Cookeconcha, Nesodiscus, Gambiodonta,
and Thaumatodon show some variations. The genera
with strong variations are also those in which there is
a great range in the degree of apertural narrowing
achieved by the barriers (table XLVIII). Both size and
number reduction of the barriers are involved in this
pattern.
Genera with a predominance of 2 parietals include
Cookeconcha and Endodonta from Hawaii, Orangia,
Taipidon, and Libera. Minidonta, Australdonta, Opa-
nara, and Aaadonta have mostly 3 parietals, while
Thaumatodon has 4 parietals, and the Mangarevan
Anceyodonta and Gambiodonta tend to have 4 or 5
barriers. All the taxa with many parietals involve
extreme cases of size reduction for the barriers. Thus
the number of parietal barriers is tied to phyletic units
and also is involved in the degree of apertural
narrowing. Raw data on the size correlations of
SOLEM: ENDODONTOID LAND SNAILS
TABLE XLI. - PHYLETIC CORRELATION OF PARIETAL BARRIER NUMBERS
Minidonta
Mautodontha
Anceyodonta
Cookeconcha
Kleokyphus
Opanara
Rhysoconcha
Ruatara
Orangia
Australdonta
Taipidon
Planudonta
Rikitea
Nesodiscus
Nesophila
Kondoconcha
Endodonta
Pseudolibera
Li"bera
Gambiodonta
Thaumatodon
Zyzzyxdonta
Aaadonta
Priceconcha
TOTALS
0
1, 1-2
1
2
Number of parietals
2 2-3 3 3-U ^
2
6
12
5
1
l
1
5
1
3
1
1
2
1
8
IT
l
many
12
3
2
1
8
1
3
5
2
1
2
1
5
U
l
l
l
2
1
1
2
1
8
3
6
19
25
1
8
parietal barrier number (table XLII) require inter-
pretation. The larger size of those taxa with only 1
parietal reflects the concentration of this state in
species of Cookeconcha and Nesodiscus in which the
apertural narrowing function has, for all practical
purposes, been lost. Similarly, the larger size of those
taxa with 2 parietals results from the phyletic units
Endodonta and Libera clustering there. The large
standard errors of the mean show that there are not
significant size differences between barrier numbers,
but that this relates more to phyletic unit and degree
of apertural narrowing.
The number of palatal barriers is basically 4 in
the Endodontidae (table XLIII), with changes to
3, 5 or total loss of palatal barriers the most common
alterations. Addition of a 5th palatal has happened in
several different ways. Most Aaadonta, Kleokyphus
callimus (fig. 95b), Endodonta lamellosa, and E.
marsupialis (fig. 167a) have an extra subpe-
ripheral barrier; in Australdonta (fig. 127a, b) it is
possible that descent of the former columellar barrier
onto the lower palatal wall has been completed;
Rhysoconcha (fig. 112) and Minidonta micraconica
(fig. 65b) have extra supraperipheral barriers; while
PATTERNS OF MORPHOLOGICAL VARIATION
69
TABLE XLII. - SIZE CORRELATION OF PARIETAL BARRIER NUMBERS
TABLE XLIII. - PHYLETIC CORRELATION OF PALATAL BARRIER NUMBERS
Number of
parietal Number
barriers of taxa
X D
7.146
X W
7+
1, or 1-2 19 5.31±0.1»1 5.9^0.23
(2.90-11.19) (k 3/8-8)
6k U. 66*0.20 5.88±0.13
(1.79-8.99) (3 5/8-8)
2 or 3 k 3.63±0.29 5.UO+0.18
(3. 01-!*. 33) (5-5 3/U)
3 U 9 3.22±0.13 5.33±0.09
(1.68-6.60) (U-8)
3 or U
It
5 3.^1*0.25
5.69±0.25
22 3.81+0. U6 5.76±0.19
(2.00-12.26) (U-7 1/2)
1* or 5 2 3.08±0.15 6.00+0.1*3
^ (2.93-3.23) (5 1/2-6 1/2)
5 7 3.1(0±0.1»2 6.03±0.19
(2.20-5.07) (5 3/8-6 3A)
many
threadlike 6 !».98±1.28 5.>*0±0.17
(3.21-11.29) (1* 3A-5 7/8)
Kondoconcha othnius (fig. 162b) has both enlarged the
upper palatal and added another supraperipheral
palatal barrier. Reduction to only 3 palatal barriers
generally involves loss of the supraperipheral barrier,
as in Minidonta inexpectans (fig. 62d) and some
Aaadonta (fig. 206b), or by elimination of a subpe-
ripheral barrier, as in many Libera (figs. 173d).
Unlike the number of parietal barriers, there is a
rather clear size correlation with the number of palatal
barriers (table XLIV). Although the large standard
errors of the mean for the diameters indicate a large
amount of variability, the trend itself is obvious.
Table XLV reviews the correlations between
numbers of parietal and palatal barriers. There is
generally central clustering. The pattern of reductions
in both sets has been described above.
Barrier length is a difficult measurement to make
and one that is subject to considerable error, since the
distance must be judged by looking into the aperture
at an angle. In addition, the growth pattern outlined
above would mean that the length of barriers would
vary according to the stage in the growth cycle at
which the animal died. Given the above factors, the
cited lengths should be taken for what they are,
estimates of relative length and not firm figures.
Figure 43 shows how length was estimated, as an arc
of a circle to the nearest sixteenth. The pattern of the
parietals, normally extending anteriorly of the lip edge,
permits seeing slightly more than one-fourth of a
whorl from its anterior termination. If the sharp
posterior descension could be spotted, but not the
actual posterior margin, it was scored as "to the line of
Minidonta
Mautodontha
Anceyodonta
Cookeconcha
Number of palatals
1, 1-2, 2 3 3-5 It
1
I
many
Orangia
Australdonta
Taipidon
Planudonta
Rikitea
Hesophila
Nesodiscus
Kondoconcha
Endodonta
Pseudolibera
Libera
3
9
2
10
2
12
3
1 It
2
1
1
9
1
2
3
5
1
1 2
5
1
1 7
1
1
Gambiodonta
Thaumatodon
Zyzzyxdonta
Aaadonta
Priceconcha
TOTALS
5
-•5
6
22
13
1
2
23
It
1
25
vision" or "one-quarter whorl," depending on the
degree of anterior extension. Extending the same
principle to measuring the palatal barrier length was
simple, but this means that comparisons of parietal
and palatal lengths is not possible, since the two arcs
are at different distances from the shell axis. In Figure
43, the solid lines indicate the arc for a one-quarter-
whorl long parietal barrier, while the dotted lines
indicate the length of a palatal barrier, in this case
about one-eighth whorl long.
TABLE XLIV. - SIZE CORRELATION OF PALATAL BARRIER NUMBERS
Number of
palatal Number
barriers of taxa
X D
X W
0
21 5.03±0.52 5.28±0.l8
(2.90-11.19) (l*-7)
1-2 lit 5.68±0.60 6.50±0.28
(1.97-11.29) (U 3A-8)
3 22 1*.99±0.1*7 6.00±0.2l(
(1.68-12.26) (l»-7 5/8)
3-5
!*.l6±0.35 5.51±0.ll*
(2.70-5.17) (5-6 lA)
It 85 3.71±0.ll* 5.65±0.08
(1.73-8.99) (3 5/8-7 5/8)
5 2k 3.51±0.26 5.>»6±0.ll*
(1.97-7.20) (it lA-7 1/2)
many k 3.76±0.3>t 5-98+0.10
(»t. 13-5. 77) (5 3A-6 lA)
TABLE XLV. - CORRELATION OF PARIETAL AND PALATAL BARRIER NUMBERS
Number of
parietals
Number of palatals
1-2
2-3
many,
a few high
many,
none high
no
data
1-2
2-3
3-5
5-6 many
1
8
U
3
1
2
1
2
5
1
1*
1
12
3
28
6
2
1
3
1
1
6
2
30
9
3
2
1
2
13
6
1
2
7
1
2
3
1
TABLE XLVI. - PARIETAL BARRIER LENGTH AND SIZE CORRELATIONS
Length of
parietal barriers
Number
of taxa
X diameter
X whorl count
l/8th whorl
1
3.88
5
.25
less than 3/l6ths
11
3. It 6*0. It li
5
.28+0.37
3/l6ths
31*
3.7810.25
5
.U6+0.17
less than 1/Uth
21
3.9110.29
5
.7310. lit
1/ltth
33
3.5210.22
5
.18+0.11
more than 1/ltth
18
3.26±0.l6
5
,5710. lit
to line of vision
16
It. 14*0.28
6,
.7810.18
beyond line of vision
Ult
lt.92tO.3li
6,
,0610.13
TABLE XLVII. - PALATAL BARRIER LENGTH AND SIZE CORRELATIONS
FIG. 43. Method of measuring parietal (solid linel and palatal
(dotted line) barrier lengths.
Length of
palatal barriers
Number
of taxa
X diameter
X whorl count
less than l/8th
13
3.614+0.29
5.l6±0.l8
l/8th
69
>4.11*10.22
5.7710.11
3/l6ths
38
U.10±0.2li
5.85*0. Ill
1/ltth
18
3.57±0.21
5.7110.12
line of vision
It
3.2110.U2
6.0liio.l9
beyond line of vision
9
3.87±0.58
6.0510.36
70
PATTERNS OF MORPHOLOGICAL VARIATION
TABLE XLVIII. - DEGREE OF APERTURAL NARROWING BY BARRIERS
71
Genus
Minidonta
Mautodontha
Anceyodonta
Cookeconcha
KLeokyphus
Opanara
Rhysoconcha
Ruatara
Orangia
Australdonta
Taipidon
Planudonta
Rikitea
Mesophila
Nesodiscus
Kondoconcha
Endodonta
Pseudolibera
Libera
Gambiodonta
Thaumatodon
Zyzzyxdonta
Aaadonta
Priceconcha
Total
taxa
15
IT
12
16
2
12
2
h
5
12
11
k
1
2
10
1
8
1
19
7
9
1
9
1
181
Strong
2
8 (1-)
2 (2-)
2
1 (IH
1
1 U-)
1 (1-)
6
7
2
1
2 (1-)
36 (7 )
Apertural narrowing
Moderate
8
5
(-1) U
3
2
8 (2-)
1
1 (1-)
U (1-)
5 (5-)
(-1) 7 (1-)
Weak
5 (2-)
6
(-2)
1
1
3
1
(-1)1 1
(-1)10 (1-*) (-3) 7
HO 7 (1-*)
HO 7
J^
( 12)7U (12 ) ( 5)30 (2 )
Not
6
7
It
2
U
2
10
1
2
There is no major correlation of parietal barrier
length and size (table XLVI) until the very elongate
barriers are encountered. Those that extend to or
beyond the line of vision are found in species with
higher whorl counts (and thus larger size). Most
probably this is a simple release pattern. Whatever
triggered the adding of additional whorls also slowed
the posterior resorption phase of barrier growth, or the
barriers simply lengthened proportionately to the
increment in whorls. Palatal barrier length correlates
probably more with palatal barrier shape changes
(table XXXII) than it does with size (table XLVII).
Short barriers are a prelude to loss of the barriers.
Degree of apertural narrowing
The most fundamental functional significance of
barriers is the degree to which they effectively narrow
the aperture. Ideally this should have been quantified
in some manner. An obvious procedure would have
been to measure the cross-sectional area of the
aperture in a plane through the expanded portions of
the barriers, subtract from this the area that is open
between the barrier tips, and then calculate the per
cent of the aperture that is walled off by the barriers.
Unfortunately, this proved to be impractical, since
sufficient material to permit sectioning each species
through the barriers was not available. In many
species, such as Libera (fig. 182) and Gambiodonta
72
SOLEM: ENDODONTOID LAND SNAILS
(figs. 187a, c), the elevated portions of the barriers are
recessed essentially beyond the line of vision from the
aperture. Thus even direct visual estimates of the
degree to which the apertures are narrowed become
subjective.
The degree of narrowing obviously varies widely.
In all Nesodiscus and taxa with reduced barriers, such
as many Mautodontha (fig. 78) and Cookeconcha (fig.
94), the aperture is virtually unimpeded by the
barriers. In contrast, taxa such as most Anceyodonta
(figs. 81, 82, 83) and Endodonta (fig. 167) have the
aperture almost closed by the thicket of protruding
barriers.
An estimate of relative closure is tallied in Table
XLVIII. The number of taxa that are intermediate in
character have been indicated in parentheses and are
accompanied by directional arrows. Genera such as
Anceyodonta and Gambiodonta share common an-
cestry, with the latter retaining strong apertural
constriction despite their large size, as do the Hawaiian
ground-dwelling Endodonta, although many Cook-
econcha that are almost equivalent in size have almost
completely lost their barriers. Where a variety of
relative constrictions is found in a genus, such as
Minidonta, Mautodontha, Cookeconcha, and Taipi-
don, there has been drastic size reduction of the
barriers (table XXXVII). As an indication of the
different states, reference is made to species of
Minidonta, which range from strongly restricted to
nearly no major narrowing. Minidonta micro (fig. 63a)
is strongly narrowed; M. micraconica (fig. 65b),
moderately; M. hendersoni (fig. 63c), weakly; and M.
planulata (fig. 69b) tends towards virtually no effec-
tive apertural narrowing, a state achieved in such
species as Mautodontha subtilis (fig. 77d).
At least one additional factor is involved, the body
whorl contour (fig. 14A-E). Species with the body
whorl laterally compressed (fig. 14A), such as Mau-
todontha maupiensis (fig. 76a), will have the aperture
more constricted than species with an evenly rounded
periphery, such as Mautodontha subtilis (fig. 77d),
even though the actual height of the barriers may be
virtually identical in the two species. The probable
extent of this correlation is shown in Table XLIX.
TABLE XLIX. - CORRELATION OF APERTURAL NARROWING AND BODY WHORL CONTOUR
Body whorl
Compressed
laterally
Evenly
rounded
Strong
6
Ik
Apertural narrowing
Moderate Weak
19 li
15
23
12
5
12
8
Taxa with evenly rounded peripheries tend to have
much less apertural narrowing than do those taxa with
either laterally compressed or keeled peripheries.
Formation of a keel would automatically tend to
accentuate the degree of apertural narrowing by the
barriers, as would the lateral compression of the body
whorl. But the latter change may be directly selected
for because of the aperture narrowing, while keel
formation (pp. 21-23) may be more of a means of
lessening shell height, with the apertural narrowing a
secondary feature.
Some of the largest (Endodonta, Gambiodonta)
and some of the smallest (Minidonta, Cookeconcha)
taxa have strongly narrowed apertures, so data on
overall size are not presented. Often, within a
particular genus, species with strongly constricted
apertures will be smaller in adult size than those with
little or no apertural narrowing. This is obvious in
Anceyodonta, where the eight species with strongly
constricted apertures have an average mean adult
diameter of 2.54 mm., while the four species with only
moderately constricted apertures have an average
mean diameter of 3.42 mm. Taipidon petricola petri-
cola, the only species in that genus with a strongly
constricted aperture, is the smallest in the genus.
Similarly, the shift from "moderately" to "weakly" to
"not constricted" in Australdonta is size correlated,
the respective average mean diameters being 3.38 mm.,
3.95 mm., and 4.19 mm. Thus within a lineage there
may be a tendency for barrier constriction reduction to
correlate with size increase, but there is no overall
pattern.
Summary of barrier variation
Much of the variation in structure, reduction, and
numbers of apertural barriers in the Endodontidae is
correlated with phyletic factors rather than size. There
is no equivalent in respect to the apertural barriers to
the apparent triggering size of 4.75 mm. after which
drastic radial rib reduction occurs (pp. 47-49). The
degree of superior expansion to the barriers does
correlate partly with small size, but lack of any
expansion is a correlative of barrier reduction rather
than of shell size. Relative expansion of the parietal
and palatal barriers is not closely correlated. Recession
of the palatal barriers does correlate with size change,
but shape and form of the barriers correlate with each
other, not shell size. Similarly, there are correlations in
form and position of the columellar barriers, but these
are independent of shell size.
Within phyletic lines there are tendencies toward
barrier size reduction and lessened degree of apertural
constriction, both of which correlate to some extent
with increased size within that lineage. But this varies
from lineage to lineage in terms of what size is reached
before major barrier reduction occurs. As a result of
the above data, I have confidence that apertural
barriers carry a high information content for phyletic
deductions.
GROSS ANATOMY
This monograph covers 185 species-level taxa. No
material was seen of six previously described species.
The dissections include 58 taxa, whose phyletic
PATTERNS OF MORPHOLOGICAL VARIATION
73
TABLE L. - PHYLETIC REPRESENTATION OF DISSECTED TAXA
Genus
Minidonta
Mautodontha
Anceyodonta
Cookeconcha
IQeokyphus
Opanara
Rhysoconcha
Ruatara
Orangia
Australdonta
Taipidon
Planudonta
Rikitea
Nesodiscus
Nesophila
Kondcconcha
Endodonta
Pseudolibera
Libera
Gambiodonta
Thaumatodor.
Zyzzyy.dorvto.
Friceconcha
Aaador.ta
Totals
Total taxa
15
17
12
18
2
12
2
k
5
12
11
ll
1
1
10
1
19
7
9
1
1
_9
185
Number seen
15
17
12
16
2
12
2
1*
5
12
11
It
1
8
2
1
8
1
19
7
9
1
1
_9
179
Number dissected
1
2
11
2
2
1*
2
6
3
2
1
3
6
58
distribution is summarized in Table L. Partial speci-
mens of Opanara areaensis microtorma, Orangia
cookei tautautuensis, and Kondoconcha othnius were
also seen, but the material was too fragmentary or
poorly preserved for successful illustrations to be
prepared or measurements made. The major phyletic
gaps in the coverage are in the Mangarevan radiation
(many Minidonta, and all Anceyodonta, Gambio-
donta, and Rikitea}, Minidonta, Mautodontha, and
Kleokyphus. Cooke (1935, pp. 41-42) reported that the
complete destruction of native forest on Mangareva
had occurred prior to 1934, although obviously live
collected native land snails from the island were added
to museum collections as late as 1872. Similarly, the
collections on the Tuamotus have yielded virtually no
living endemics in this century. The faunas of these
two areas include Pseudolibera, both Kleokyphus,
Mautodontha daedalea, five species of Minidonta, all
Anceyodonta, all Gambiodonta, and Rikitea insolens,
for a total of 30 species-level taxa. If these groups are
eliminated, then 38.9 per cent (58 of 149) species-level
taxa were dissected at least in part. This section
includes data on Thaumatodon spirrhymatum and
Priceconcha tuvuthaensis, the species described in
Solem (1973d).
Because of the fragmentary material available for
dissection in many species, information concerning
apical organ systems frequently is lacking. For ex-
ample, the origin of the penial retractor muscle could
be observed in only 40 of the 58, the length of the
pallial cavity in 35, and the character of the ovotestis
in 37 taxa. Penial length was measurable, however, in
54 of the 58 taxa. Within these limitations of materials
and successful observations, the following pages review
the observed patterns of variation in structure,
delineate the topographic anatomy of the body,
compare and contrast these features with equivalent
structures as observed in the Pacific Island Charo-
pidae, and occasionally add comparative remarks from
dissections of Australian, New Zealand, New Caledo-
nian, and Lord Howe Island taxa. These additions are
background data necessary to establish the importance
assigned variations in structure against the context of
a broader scope investigation. While comparisons of
the endodontid shell variation with the Charopidae
have been deferred until the second monograph, the
anatomical data are presented here.
The sequence of structures places the genital
system first because of its higher information content
concerning phylogeny within the family.
GENITAL SYSTEM
The terminology used below is modified from that
of H. B. Baker (1938b, pp. 6-10, 92), since it more
adequately reflects the apparent functioning of the
system than does the terminology used by English
workers such as Rigby (1963, 1965). The latter system
was developed by forced comparisons of prosobranch
and very advanced pulmonate taxa. It is not transfer-
able to description of less specialized pulmonate taxa.
Many of the fusions and specializations found in the
advanced taxa have not taken place in the more
generalized families. A recent commentary (Bayne,
1973) also basically adopts the Baker terminology. The
abbreviation used in the illustrations follows each
term.
OVOTESTIS (G) - The hermaphroditic gland or
ovotestis is located above the reflexion of the intestine
from the stomach apex. Typically it consists in the
Endodontidae of many multilobate alveoli strung
along a single collecting tubule. Typical patterns are
shown in Figure 164a for the sequential relations of
the alveoli along the collecting tubule and Figure 165e
for the palmately clavate branching pattern of a single
unit. The collecting tubule runs along the lower
parietal wall of the whorl cross-section, ascending for
one-third to two-thirds of a whorl, depending on the
length of the ovotestis. I have no data on seasonal
variation in development of individual follicles or
length of the entire organ. Preservation in this area of
the animal generally was poor. This dictated drawing
only that portion which could be extracted easily, so
that apparent differences in ovotestis lengths shown in
the drawings are artifacts of dissection resulting from
preservation problems. In the Endodontidae there is a
single characteristic pattern of ovotestis orientation.
74
SOLEM: ENDODONTOID LAND SNAILS
FIG. 44. Ovotestis structure and position in the Endodontidae (a-
6) and Pacific Island Charopidae (c-e): a, typical pattern as seen in
Endodonta fricki; b, pattern after nuclear whorl enlargement as seen
in Nesophila tiara; c, typical pattern in the Pacific Island
Charopidae as seen in the Tongan species usually known as
"Charopa" vicaria (Mousson, 1871); d, pattern seen in Aeschro-
domus stipulata (Reeve, 1852) from Pelorus Bridge, Marlborough,
New Zealand (FMNH 165395), probably correlated with changes in
coiling pattern and whorl size; e, pattern seen in Thalassohelix
propinqua (Hutton, 1883) from Weka Pass, Waikari, South Can-
terbury, New Zealand (FMNH 165399) and associated with size
increase of the whorl cross-section. (CK)
This is shown in Figure 44a. The follicles extend
upward and outward at an acute angle to the shell
axis. Often they reach from the lower parietal to the
upper palatal margin, being imbedded in digestive
gland tissue. Up to a full whorl or whorl and a half of
digestive gland tissue extends above the ovotestis apex.
This is modified in only three of the dissected
taxa. In Nesophila tiara (Mighels) and Cookeconcha
jugosus (Mighels) (figs. 165d, h; 44b) the follicles have
a right angle radial orientation to the shell axis,
instead of sitting at an acute angle, while in both
species of Rhysoconcha (p. 255) the follicles are
reduced in number and lie essentially parallel to the
plane of coiling. Cookeconcha jugosus is 25 per cent
larger in diameter than an apparently related species,
C. hystricellus (Pfeiffer), with virtually identical whorl
count. The latter species (fig. 165j) retains the normal
positioning of the ovotestis. Nesophila tiara has a
mean shell diameter of 11.29 mm. with an average of
slightly less that 5V& whorls, while the other studied
Nesophila, N. capillata (Pease), has a mean diameter
of 4.46 mm., with slightly less than 4% whorls. Visual
inspection of these four species shows that the apical
whorls of the pair with altered ovotestis orientation
are significantly larger than those of their smaller
relative. The ovotestis orientation in N. capillata is
unknown. The shell size increase in these taxa resulted
not from the addition of more whorls, as is the pattern
in Nesodiscus and Libera, but from proportionate
change in whorl size without increase in whorl
number. Thus the shift of ovotestis orientation in the
Nesophila and Cookeconcha probably reflects the
sudden availability of extra space in the upper whorls,
and not any shift in genital structure itself. As
presented elsewhere (pp. 255-256), the change in
follicle orientation seen in Rhysoconcha is one of the
features that led me to propose that this is an example
of secondary size reduction.
The Pacific Island Charopidae have ovotestis
patterns that stand in great contrast to those found in
the Endodontidae. The typical charopid pattern (fig.
44c) is for one or two clusters of palmately clavate
alveoli to extend virtually horizontally from the
stomach apex toward the apex of the viscera. A single
clump will extend as shown; the second clump, when
present, will lie apicad of the first, separated from it by
a distinct zone of digestive tissue. In such taxa as
Aeschrodomus stipulata (Reeve, 1852) (fig. 44d) from
New Zealand, which have an altered shell shape with
high spire, the two clumps may nearly fill the whorl.
Only the narrowest strips of digestive gland tissue
extend anteriorly. Multiple experiments in size in-
crease have occurred in the Charopidae, with forms
such as the New Zealand Thalassohelix propinqua
(Hutton, 1883) (fig. 44e) showing nearly right angle to
the shell axis orientation for the follicles. The basic
two-clump format is clearly visible, despite the
convergence to the endodontid patterns (fig. 44a, b). In
regard to Micronesian, Polynesian, and Melanesian
PATTERNS OF MORPHOLOGICAL VARIATION
75
taxa, the difference in ovotestis structure is diagnostic
at the family level.
The Charopidae not only have fewer and
proportionately larger alveoli in the ovotestis, but they
are oriented and clumped differently from the follicles
found in the Endodontidae. Observed changes in the
follicles seen in the Endodontidae correlate with major
shifts in growth pattern, either increase in whorl cross-
sectional area (Nesophila and Cookeconcha jugosus)
or probable secondary size reduction (Rhysoconcha).
HERMAPHRODITIC DUCT (GD) - This is an
expanded continuation of the joined collecting tubules
of the ovotestis follicles that extends to the carrefour
region. In nearly all generalized shell-bearing pulmo-
nates, this tube extends along the parietal or lower
parietal margin of the whorl beneath or adjacent to
the stomach. The function of this tube is to transport
sex products. Its existence as a separate organ may be
the result of simple space problems. The stomach
occupies the same part of the visceral hump as the
hermaphroditic duct, the space-consuming ovotestis
lies above the stomach expansion and initial intestine
reflexion, while the large albumen gland occupies the
area below the stomach. The hermaphroditic duct
provides an essential narrow passageway through the
zone occupied by the main expansion of the digestive
tract. In 32 of the examined Endodontidae, the
hermaphroditic duct is a simple expanded tube (fig.
45a). The outer edge may have a few humps or
wrinkles in it, but the inner surface is smoothly and
evenly curved. Inspection of the drawings scattered
through the systematic section shows major differ-
ences in degree of expansion and the extent to which it
is obviously reflexed anteriorly before joining the
carrefour. The expansion differences probably vary
with the state of reproductive activity, while the exact
degree of reflexion more probably reflects the state of
contraction of the animal when preserved. The
existence of a slight reflexion in the talon area is
normal, but this often is accentuated in contracted
animals. Presumably this is caused by apical move-
ment of the pallial apex forcing the albumen gland
and intestinal loops slightly above the stomach
expansion by compressing the early part of the
stomach. The permanent bend in the hermaphroditic
duct permits varying lengths to be reflexed upward.
Artificial straightening of the reflexed section can
happen quite easily while pinning out a dissection for
drawing. Thus apparent changes in this section of the
genital system as illustrated have no significance.
What does seem to have significance is the degree
to which the duct is kinked or partly coiled. This is
shown most completely by Aaadonta kinlochi (fig.
45d) and only slightly less so in Ruatara oparica
normalis (fig. 64h) and R. o. reductidenta. In Cooke-
concha jugosus (fig. 165h) the middle half of the duct
is kinked, while in Thaumatodon euaensis (fig. 195c)
and Aaadonta fuscozonata fuscozonata (fig. 199e) the
FIG. 45. Hermaphroditic duct variation in the Endodontidae: a,
typical pattern; b, slight kinking as in Thaumatodon hystricelloides;
c, moderate kinking as in Aaadonta constricta; d, extensive kinking
as in Aaadonta kinlochi. In each drawing the ovotestis would be on
the left and the reflexion to the carrefour on the right. (CK)
upper half of the duct is kinked. In Thaumatodon
hystricelloides (fig. 45b) the top quarter is coiled, as is
the top third in Aaadonta c. constricta (fig. 45c). The
differences between the several states are shown and
suggest that a progressive pattern of kinking from the
apex is normal. The normal pattern in the Charopidae
from the Pacific Islands also is for a simple her-
maphroditic duct, but coiling occurs in many
Austrozelandic taxa, such as Allodiscus dimorphus
(Pfeiffer, 1853). Generally the duct in the Charopidae
is thicker, shorter (corresponding with a general
tendency toward fewer whorls in that family), and
appears more highly iridescent than those from
endodontid species.
Viewed within the context of their lineages, the
few endodontid taxa with coiled or kinked hermaphro-
ditic ducts show no clear shell correlations with each
other. Kinking has occurred in flat-spired, large species
(A. kinlochi and C. jugosus), relatively small species
with spires that protrude much higher than normal
04. c. constricta, A. f. fuscozonata, T. euaensis, and R.
o. reductidenta) and species with a median spire
projection (T. hystricelloides and R. o. normalis). The
phenomenon is not associated with whorl increase and
high spire, as in Libera and Nesodiscus, but with spire
protrusion while retaining a normal, or even slightly
lowered whorl count (A. kinlochi, T. euaensis, A. c.
constricta). In the Austrozelandic Charopidae, kinking
is, in general, associated with visceral hump reduction,
changing in coiling patterns of the shell, and major
size increments.
Thus kinking of the hermaphroditic duct in the
Endodontidae should be viewed as having occurred
independently in each genus. The presence of a kinked
duct in an endodontoid genus should be taken as a
signal that changes have occurred from the visceral
76
SOLEM: ENDODONTOID LAND SNAILS
hump coiling or protrusion pattern found in its
ancestors. The reasons for kinking rather than simple
shortening of the duct is unknown. There could be
functional significance requiring a minimum duct
length. It could be merely an accident of development,
with the trigger that results in shortening the stomach
failing to influence the development of the duct itself.
Although no measurements were taken as docu-
mentation, simple observation confirms that the
longer the stomach, the longer the hermaphroditic
duct, since it serves to convey sex products from a
large organ above the stomach to a large complex of
organs below the stomach.
TALON (GT) and CARREFOUR (X) - Consid-
erable controversy exists concerning the structure and
function of organs in this area. Many English workers
refer to this as the "receptaculum complex" (Rigby,
1965, pp. 455-457), have called the lower portion of the
hermaphroditic duct a "seminal vesicle," and inferred
that there are functional divisions into a "fertilization
sac" and two "receptacula seminis" in Succinea and
zonitids such as Oxychilus (Rigby, 1963, pp. 328-329,
fig. 7). In the Bulimulidae, Van Mol (1972, pp. 199-202)
reported a highly complex talon structure, part of
which is a fertilization chamber. In other taxa, such as
the Australian camaenid genus Craterodiscus, there is
no differentiated structure in the area where the
hermaphroditic duct joins the albumen gland,
prostate, and uterus (Solem, 1973c, p. 379, fig. 1, d).
Similarly, in the Tornatellinidae (Cooke and Kondo,
1960, pp. 31-33) the structures can be greatly reduced
(as for example in Tekoulina, Solem, 1972b, p. 101, fig.
3, b) or with an accessory, very large organ (Cooke and
Kondo, 1960, pp. 31-33, fig. 8). In contrast to this, both
the Endodontidae and the Charopidae have a relative-
ly simple structural arrangement. The talon (GT) is a
bulbous expansion sitting on a shaft that may be
extremely short (most Charopidae) to usually quite
long (many Endodontidae) and that emerges from the
carrefour (X) apex. There is no external indication of
any subdivision to the talon. In several exceptionally
well-preserved specimens it was possible to examine
this region in some detail.
The Endodontidae have variation in the talon
shaft length. Of the 41 taxa in which this could be
observed, 25 had a long shaft, as in Endodonta fricki
(fig. 164b); seven had a medium length talon shaft, as
in Aaadonta c. constricta (fig. 199c); and nine had a
short talon shaft, as in Thaumatodon euaensis (fig.
195c). These variations are only partly phyletically
associated. Of the genera in which two or more species
could be scored, Cookeconcha, Rhysoconcha, Orangia,
Australdonta, and Libera had only long talon shafts.
Both Planudonta in which the talon could be observed
had short shafts, but the four Taipidon had two with
short and two with long shafts. Opanara has species
showing all three states, while Aaadonta, Thaumato-
don, and Taipidon have species with two states.
The situations involving mixed shaft types within
genera or involving derivative genera (Taipidon and
Planudonta) require special examination. In Opanara,
short shafts are possessed by O. bitridentata (fig. 96c)
and O. duplicidentata (fig. 96g); medium-length shafts
by two subspecies of O. areaensis (fig. 96j); and long
shafts by O. altiapica (fig. 97a) and O. megomphala
tepiahuensis (fig. 97e). These are the only species in
that genus for which this character was observed. O.
areaensis microtorma, O. duplicidentata, and O.
bitridentata are sympatric at Stations 446 and 451 on
Mt. Perahu, while the nominate race of O. megom-
phala occurs with O. areaensis at Station 477. O.
duplicidentata and O. bitridentata differ markedly in
penial length (1.5 and 2.65 mm. long, respectively),
pilaster pattern (figs. 96d, h), and origin of the
columellar retractor muscle. O. areaensis has the penis
length and columellar muscle origin of O. bitridentata,
but modified pilasters (fig. 96k). The other Opanara
mentioned above also differ in penis size and pilaster
patterns.
Of the Marquesan species, Taipidon semi-
marsupialis (fig. 139a), T. fragila (fig. 138e), Plan-
udonta intermedia (fig. 147a) and P. concava (fig.
147c) have short talon shafts, while T. petricola
petricola (fig. 138a), T. p. decora (fig. 49a), and T.
centadentata (fig. 139e) have long talon shafts. Both
Planudonta, T. semimarsupialis, and T. centadentata
are sympatric on Mt. Ooumu, Nukuhiva Island.
Taipidon fragila from Hivaoa essentially is sympatric
with T. varidentata, a species whose talon length is
unknown, while the two races of T. petricola are the
only endodontids known from Eiao and Hatutu
Islands.
The several Thaumatodon and Priceconcha are all
allopatric, but they have short, medium, or long
talons. In Aaadonta constricta and A. fuscozonata,
which were collected together at Station 203 on
Peleliu and Station 221 on Koror, there are apparent
differences in talon length.
Because of the allopatric variability in Thaumato-
don the evidence is not fully conclusive, but there is a
strong correlation of talon shaft length variations
occurring under conditions of congeneric sympatry.
This suggests that this feature may be involved in
species isolating phenomena. Much more study is
needed before this can be stated as a fact or disproved.
Certainly the variations are repeated in several
phyletic units, so that selection on a relatively low
level would be involved. Because of its numerical
frequency and broader geographic distribution, I
conclude that the long talon shaft is the generalized
state in the Endodontidae.
The carrefour (X) is a barely noticeable to
prominent swelling in the gonoduct that usually lies
partly buried in the surface of the albumen gland
(GG). It receives ducts from the hermaphroditic duct
(GD), talon (GT), and albumen gland (GG). Separate
PATTERNS OF MORPHOLOGICAL VARIATION
77
ducts exit to the uterus (UT) and prostate (DG). In
several taxa, preservation was excellent and the
apparent relationship of these ducts could be observed
using transmitted or reflected light at 64X-100X
magnification. Generally the albumen gland tissue was
teased away, the ducts of the uterus and prostate
separated, then the isolated carrefour area placed in a
temporary glycerine mount on a depression slide for
study. The species for which such detailed observations
were made are Opanara duplicidentata (fig. 103a, b),
Taipidon petricola petricola (fig. 138b), Endodonta
fricki (fig. 164b), Libera micrasoma (fig. 171g),
Thaumatodon euaensis (fig. 195c), and Aaadonta
constricta constricta (fig. 199c). Inspection of these
figures shows that the talon inserts either directly on
the head or slightly to one side of the head of the
carrefour. The hermaphroditic duct uniformly inserts
laterally on the side of the carrefour, either just below
(O. duplicidentata} or well below the carrefour head.
The albumen gland duct is drawn as entering opposite
the hermaphroditic duct in Opanara duplicidentata,
but this needs confirmation. Since it was the first of
these species studied and illustrated, this structure
could have been misinterpreted. The other species
show the albumen gland duct entering after the
uterine duct has separated from the prostate. In
Libera micrasoma and Aaadonta c. constricta it was
possible to indicate the internal duct passageways.
These appear in transparency to be simple tubes.
The situation in the studied Charopidae is quite
comparable, with different species having short or long
talon stalks, but generally the talons of charopids have
a distinctly circular head, resembling a golf ball on a
tee, while that of the Endodontidae is elongately
ovate, and there is a greater tendency for the carrefour
not to show any expansion in the Charopidae.
Histological studies are needed to work out the
significance of these reported differences and to
establish the exact structures involved.
ALBUMEN GLAND (GG) - This mass of
alveolar tissue is situated just above the pallial cavity
apex and nestled in the loop of the intestines just
below or at the point where the narrow esophagus
widens to form the stomach. The albumen gland varies
greatly in size from individual to individual, often has
its surface indented by the head of the spermatheca
and intestinal loops, and fragments upon handling.
Most typically, whether the snail is contracted or
expanded, a well-developed albumen gland lies next to
the upper parietal wall. It will be broadest at the base,
tapering to a narrow rounded tip just before the
stomach expansion reaches the upper parietal margin.
The spermathecal head lies at its base, next to the
parietal wall, and between the albumen gland base and
the kidney base. The intestinal loop that indents the
kidney margin lies between the spermathecal head and
the palatal wall. When reduced in size, the albumen
gland may lie in the midwhorl section rather than
being pressed against the parietal wall. Because of its
variability in size, the necessity to remove tissue in
order to examine the talon, and its general delicacy of
structure, no attempt was made to show the albumen
gland in complete form.
Compared with the Charopidae, the alveoli were
smaller and the shape less variable in the Endodon-
tidae. Charopid taxa have the albumen gland tightly
jammed between the intestinal loops with the surface
deeply indented by other structures. The gland has
distinctly larger alveoli and is more ovoid than
elongated in shape. Probably this relates to the fact
that the Charopidae from Pacific Islands have a
median whorl count of 4!/s- compared with a median
of 5!/2 + for the Endodontidae. Shortening of the
visceral hump coiling resulted in less space for
"stringing out" the organs and hence greater
compaction in the area between the pallial cavity apex
and the stomach expansion.
PROSTATE (DG) and UTERUS (UT) - Most
European workers have preferred the term "spermovi-
duct" for this region, reflecting the fact that in most
European pulmonates there is a morphologically
united common duct that is physiologically differ-
entiated into male and female tracts. Good descrip-
tions of the tract histology for this area in advanced
land snails are given by Van Mol (1972, pp. 202-207)
for the Bulimulidae and by Rigby (1965) for the
Succineidae. The Charopidae agree with this pattern in
having the ducts fused, but with a simpler pattern of
differentiation than was seen in the above mentioned
groups (Solem, unpublished). The Endodontidae differ
in having the prostate and uterus entirely separate
tubes that are very loosely bound together by a few
connective tissue strands. Elsewhere (Solem, 1972b, pp.
108-112) I have reviewed the pattern among pulmo-
nate snails of variation in fused versus separate pallial
gonoducts ( = prostate and uterus), and concluded
that fully separated ducts are the basic pulmonate
condition, with fusion of the tracts a derived character
state and advanced condition that has evolved several
times.
Throughout the Endodontidae, the prostate is a
small, thin-walled tube into which one (fig. 191a), two
(fig. 199c), three (fig. 164d), or even four or five (fig.
165a) rows of alveoli attach individually. Normally the
prostate lies on top of the uterus, with the sperma-
thecal shaft lying loosely attached on top of its duct.
The prostatic alveoli are bent toward the outside of
the whorl across the top of the uterus. The whole
bundle of genital ducts (prostate, uterus, spermathecal
shaft), esophagus, and columellar muscle occupy the
lower palatal and columellar portion of the whorl
margin, while the pallial cavity extends to the palatal
margin. The hindgut occupies the upper parietal-
palatal margin.
In the Charopidae, the prostate tissue is fused to
the uterus, with an internal channel slightly to
strongly demarcated from the uterine lumen. The
prostatic tissue is composed of even fewer and often
78
SOLEM: ENDODONTOID LAND SNAILS
more elongated alveoli that show no patterned
arrangements, rather than the large, rather short
alveoli placed in even rows that are characteristic of
the Endodontidae.
Structure of the uterus in the Endodontidae is far
more complicated, but the histological studies needed
to work out the details could not be undertaken.
Depending upon the species, there is evidence of from
two to four sections in the uterus. These range from
an always present division into a simple, thin-walled,
narrow upper chamber (fig. 164a, UTi) and a broader,
thicker walled, glandular chamber (UT:>) in the lower
section, to the situation seen in Thaumatodon hys-
tricelloides (fig. 191b). This species has a clump of
glandular tissue, clearly different in texture from that
of the albumen gland, around the head of the uterus
(UTi); the typical thin-walled, rather narrow tube
(UT-j); the expanded zone with thick glandular walls
(UT;i); and a narrower tube with very fine glandular
tissue (UTi) that lies below the termination of
prostatic alveoli and before the start of a simple tube
that I interpret as the free oviduct (UV). Presumably
the upper zone of the uterus is the section associated
with enclosure of the embryo with nutritive material
and membranes, while the lower glandular section
secretes the egg capsule. No eggs were seen inside the
uterus of any specimen dissected during this study.
Whether the more complex uterine area of T.
hystricelloides reflects a change in structure or merely
better preservation (this material initially was placed
in 95 per cent alcohol after drowning) is unknown. The
uterine area tended to swell quickly in liquids of
lowered alcohol content and few detailed observations
were made on this area, since after initial illustration
and handling it often had burst or split open.
In the Charopidae, the uterus is much more
sharply divided into two zones, with the lower
chamber having thick glandular walls and often
appearing as an ovoid structure grafted onto the
prostate surface. The difference between having totally
separate versus fused pallial gonoducts is a highly
significant one and another key character separating
the Endodontidae from the Charopidae.
Inspection of the drawings suggests that there
may be differences in the number and actual size of
the prostatic alveoli, but whether this is a variation
correlated with reproductive cycle stage or has
phyletic significance is unknown.
TERMINAL MALE GENITALIA - This
complex includes the vas deferens (VD), epiphallus (E)
(when present), penis (P), penial retractor muscle
(PR), and the atrium (Y). Differences are substantial,
primarily because species recognition presumably has
great selective influence on this region. Because of this,
description of the structural variations cannot be
separated completely from a consideration of sym-
patric interspecific variation.
The vas deferens, when prostate and uterus are
separate, must be defined as the prostatic duct below
the end of the alveoli. Its appearance varies with
preservation and possibly between taxa, but data are
meager on this latter aspect. In some taxa it appears
that the tube becomes thicker walled and reflects light
more strongly almost immediately, but in others this
change seems to occur gradually as the vas deferens
descends to the penioviducal angle. The vas may or
may not be loosely bound to the angle before reflexing
upward along the penis itself. It is effectively held in
the angle by the right ommatophoral retractor muscle
that passes through the penioviducal angle. The ascent
of the vas deferens is on the columellar side of the
penis to a point that is usually distinctly below the
head of the penis (fig. 46), although the exact point of
entry varies within rather narrow limits for any single
lineage. The entry into the chamber of the penis is a
simple pore, normally distinctly below the point of
apical union for the pilaster. The situation in
Endodonta (figs. 164a, c; 165a, d, g) is typical.
Taipidon p. decora (fig. 49a) shows an exceptionally
low entrance. The basic two pilasters of the penis
chamber unite at its apex and while drawing tech-
FIG. 46. Vas deferens entrance and penial retractor muscle
insertion patterns: a, typical (based on Cookeconcha jugosus); b,
apical vas deferens entrance (based on Ruatara oparica normalis)',
c, some added tissue to penis apex (based on Opanara megomphala);
d, moderate extra tissue (based on Opanara bitridentata); e, much
extra tissue (based on Planudonta intermedia); f, formation of a
penial epiphallus and valvular vas deferens entrance (based on
Aaadonta c. contricta). (CK)
PATTERNS OF MORPHOLOGICAL VARIATION
79
niques may suggest that the pore (EP) lies opposite
the point of union or on the same side as the point of
union in generalized taxa, this is an artifact of drawing
technique rather than an indication of structure. In
forms with altered pilaster arrangement, such as
Cookeconcha hystricellus (fig. 165j, k), the pore often
is located just below the point of pilaster union,
although externally (fig. 165j) it may appear to be
apical in its insertion. In Taipidon fragila (fig. 138e)
the penis is only 1.5 mm. long, compared with a 2.5
mm. long penis in its sympatric congener, T. vari-
dentata. The former has a distinctly more apical
insertion of the vas than does the latter. In Rhyso-
concha variumbilicata (fig. 64f, g) the vas deferens
entrance is almost apical, and in R. atanuiensis it is
apical. The two dissected races of Ruatara oparica
(figs. 46b; 64h-j) have the vas entering "just below the
apex." These situations probably are indicative of size
reduction.
The above changes represent positional minor
shifts. In contrast, there is a major change in the
Thaumatodon-Priceconcha-Aaadonta lineage. In these
genera the vas deferens enters through a pair of "lips"
or a "valve" (fig. 46f; 199d) into a reflexed zone of the
penis that lies well below the point of attachment for
the penial retractor muscle. Two pilasters extend from
this point, in varying degrees of prominence (figs. 199d;
200c; and Solem, 1973d, fig. 20, b), up to the penis
head and then into the main chamber. The length of
the reflexed portion varies, being about one-third the
penis length in Thaumatodon decemplicata, T. hys-
tricelloides, and T. spirrhymatum, one-half the penis
length in T. euaensis and all dissected Aaadonta, and
two-thirds the penis length in Priceconcha tuvu-
thaensis (Solem, 1973d, fig. 20, a).
The homologies of this area and appropriate
terminology present some difficulties. An epiphallus
usually is defined as an expanded portion of the vas
deferens that is functionally apical of the penis head.
Normally, in advanced taxa, it is involved in sper-
matophore or sperm packet formation. Presumably in
less advanced taxa it secretes fluids to carry and
provide life support for the sperm during transport. It
is not eversible and is very different from the penial
structures. Frequently, in such groups as the Helica-
rionidae (Solem 1966a, figs. 6, b; 19, a; 22, a), there are
accessory flagella or caeca on the epiphallus, and in
Indian Helicarionidae (Blanford and Godwin-Austen,
1908) highly complex and spined spermatophores are
formed in the epiphallus and its appendages. It also is
possible for an epiphallus to develop from the penis
itself and thus be a non-eversible apical chamber of
the penis. The latter situation probably applies to the
Thaumatodon- Aaadonta lineage. The altered zone lies
topographically below, although functionally above,
the penial retractor muscle and is reflexed anteriorly
in all specimens. It is extremely difficult to see how
this could be everted successfully. If this area is not
everted during copulation, it would be functionally a
"penial epiphallus." On the other hand, the reflected,
probably non-eversible area has the typical penial
pilasters found in the other Endodontidae. It is clearly
of penial origin and probably of recent origin. The
valvular arrangement at the point of vas deferens
entrance is the "new" structural feature, while the
change in penial retractor attachment, or equally
possibly the growth of the penial chamber past the
retractor muscle attachment, is a minor shift in
position. The pilaster patterns are typical of the
family. I have concluded that this is a functional
penial epiphallus of recent origin and use the term
epiphallus for the structure throughout this report and
in an earlier publication (Solem, 1973d).
The adoption of a valvular entrance from the vas
deferens and alteration of the upper penial chamber
into an epiphallus represents the most striking change
seen in the genital anatomy of the Endodontidae.
In contrast to this, the Charopidae normally have
a vas deferens-derived epiphallus, with the entrance
from the vas highly complex and variable, often
involving sphincter pilasters and/or plug-like struc-
tures. The epiphallus normally is sharply differ-
entiated from the penis and there are highly complex
and varied patterns of transition between the two
areas. In lineages that are undergoing visceral hump
reduction in the Charopidae, such as the
"flammulinid" genera Flammulina and Maoriconcha,
the epiphallus may be shifted forward into the penial
complex, thus giving an external appearance of no
epiphallic differentiation (Solem, unpublished). One
group of Micronesian Charopidae departs from the
pattern in having direct entrance of the undifferen-
tiated vas deferens into the penis head after passing
partway through the U-shaped insertion of the
penial retractor muscle (Solem, unpublished). There is
no trace of any epiphallic differentiation.
The penis in the Endodontidae is basically an
elongated tube with two pilasters extending from a
union at the apex of the penis almost to or even into
the atrium. Differences in penis length, pilaster
pattern, and structure of the pilasters are highly
influenced by interactions with sympatric congeners.
Discussion of these factors follows preliminary review
of some phyletic alterations. The Marquesan genera
Taipidon and Planudonta are unique in the family
because of developing a pustulose zone in the penis
(figs. 49b; 138h; 147b, d). The extent and position of
this glandular zone differs in the various species,
ranging from perhaps two-thirds of the penis length in
T. semimarsupialis to just the basal area in T.
petricola decora. This is an additive feature to the
genitalia and has no equivalent in other geographic
areas.
Attachment of the penial retractor muscle (PR) to
the penis itself is variable (fig. 46). In all dissected
Minidonta, Mautodontha, Cookeconcha, Rhysoconcha,
80
SOLEM: ENDODONTOID LAND SNAILS
Ruatara, Australdonta, Nesodiscus, Nesophila, Endo-
donta, and Libera the penial retractor attaches
directly onto the penis apex (fig. 46a). Upon opening
the penis there is no indication of any extra thickness
to the penis apex at or near the point of muscle
attachment. In Orangia, Planudonta, several Taipi-
don (T. centadentata, T. fragila, and T. varidentata),
and all Opanara except O. depasoapicata and O.
caliculata, there is a "fleshy extension" to the penis
apex that extends for a variable distance upward
before the penial retractor attaches (figs. 46c-e). This
partly glandular zone does not surround the muscle,
but is a new zone between the muscle and the penis
apex. The varying extent and prominence of this zone
within a genus can be seen quite clearly in Figures 96
and 97. The typical apical insertion of O. depasoapi-
cata (fig. 96a, b), weak extension in O. altiapica and
O. megomphala (fig. 97a-d), moderate extension in O.
m. tepiahuensis, O. fosbergi, and O. perahuensis (fig.
97e-h), and stout extension in O. bitridentata (fig. 96e,
f) compare with a much more even extension in the
species of Orangia (fig. 121). Taipidon shows great
variability, with direct attachment in T. petricola (fig.
49a) and T, semimarsupialis (fig. 139a, b), a long but
narrow attachment zone in T. centadentata (fig. 139e,
f), and very prominent attachment zone in T. fragila,
T. varidentata (fig. 138e, g), and the Planudonta (fig.
147). In all of the above taxa, both the union of the
pilasters and apex of the penis lie a significant distance
below the penial retractor attachment point. The
function of the added zone is not known, but a logical
possibility for investigation would be secretion of fluids
equivalent to that normally provided by the epiphallus
in more advanced taxa.
The different patterns of penial retractor attach-
ment and vas deferens entrance are summarized in
Figure 46. In essence, these seem to represent at least
two separate kinds of experiments in providing the
functional equivalent of an epiphallic zone: inter-
position of glandular tissue between the penis apex
and penial retractor muscle in several groups, and then
formation of a non-eversible section of the penis by
reflexion in the Thaumatodon-Priceconcha-Zyzzyx-
donta-Aaadonta complex. The addition of glandular
tissue to the penis apex is found in Rapan and
Marquesan genera, but not in taxa from other
geographic areas.
Much more variability is seen in the shape of the
pilasters. This is complicated in analysis by changes in
relative size shown by the two basic pilasters, and
some variability in pilaster number. Figure 47 shows
the basic cross-sectional pilaster types: low and
rounded (a); medium in elevation (6); or high and
lamellate (c). In Australdonta (fig. 125b, e) the two
pilasters are complexly folded and split into portions,
so that they do not fit into any of the above
categories. In Ruatara (fig. 64i) there is only a single
rugose pilaster for most of the penis length, which
becomes bifurcated basally, suggesting that it is a
secondary modification from the basic two-pilaster
pattern.
The low and rounded pilasters are characteristic
of the few Minidonta, Mautodontha, Endodonta, and
Aaadonta that have been dissected, plus such species
as Cookeconcha jugosus (fig. 165h), Taipidon centa-
dentata (fig. 139f), and Planudonta intermedia (fig.
147b). Those taxa in which the pilasters are higher
than wide, but rounded above if not secondarily
altered, include all Thaumatodon, Planudonta sub-
planula (fig. 147g), Nesophila tiara (fig. 165g), Neso-
discus (fig. 154), the other Cookeconcha, Rhysoconcha,
Opanara perahuensis (fig. 97i), and Orangia sporad-
ica (fig. 121k). The latter two species probably
represent secondary modifications from the normal
pattern in these genera, since the remaining Orangia
and Opanara all have high, lamellate pilasters. These
also are the normal condition in Libera, the remaining
Taipidon, Planudonta concava, Kondoconcha othnius
(p. 368), and Priceconcha tuvuthaensis (Solem, 1973d,
fig. 20, b). Whether the pilasters unite both apically
and before the atrium, as in Endodonta; extend
routinely into the atrium, as in Thaumatodon and
Aaadonta; or are variously altered is selected for at a
low taxonomic level. There is a general tendency for
those taxa with low pilasters to have union apically
and basally, while for those with very high and
lamellate pilasters there can be absence of any union
(Libera, fig. 171b) or typical union apically (Plan-
udonta, fig. 147b, d; and Priceconcha, Solem, 1973d,
fig. 20, b).
FIG. 47. Pilaster cross-sectional patterns in typical Endodon-
tidae: a, low and rounded; b, elevated but rounded; c, high and
lamellate (main pilaster) with reduced pilaster flattened or otherwise
altered. (CK)
PATTERNS OF MORPHOLOGICAL VARIATION
81
The relative size of the two pilasters is partly
phyletically correlated and partly influenced by sym-
patric factors. The two pilasters are equal or nearly
equal in size for dissected Minidonta, Mautodontha,
Rhysoconcha, Australdonta, Nesodiscus, Nesophila,
Endodonta, and all Libera except L. cookeana.
Species of Orangia, Planudonta, Thaumatodon, Price-
concha, Aaadonta, and Taipidon (except two special
cases) have the pilasters grossly unequal. Species of
Cookeconcha and Opanara have a nearly equal
mixture of both types. Ruatara oparica (fig. 64i) is
unique in that the pilasters apparently fused into a
single rugose structure that is split basally. There is no
significant correlation between pilaster shape and
relative size of the two pilasters (table LI), although a
tendency exists for the low and rounded pilasters to be
equal in size, with the higher pilasters more likely to
be unequal.
TABLE LI. - CORRELATION OF PENIAL PILASTER SHAPE AMD RELATIVE SIZE
Pilaster shape
Low and rounded
Intermediate
High and lamellate
Pilaster relative size
Equal Subequal
9 6
15
The gross data on this variation should be checked
with the patterns of sympatric variations summarized
in Tables LII through LIV. Unfortunately, I had
available for study only one example of sympatric
congeners where low and rounded pilasters were
involved. These two Tahitian Mautodontha (table
LIII) differed grossly in penial size, but not in pilaster
pattern. Their shell features (fig. 74) also are grossly
different, so that there is no question of their being
valid species. With high and lamellate pilasters,
obviously there is much more room for ex-
perimentation. Overall the genus Opanara has six taxa
with unequal pilasters and five with essentially equal
pilasters. Listing several sympatric Opanara (table
LII) shows that both penis size and pilaster changes
occur. Orangia shows equivalent shifts. In the Tahi-
tian Libera (table LIII) there is still a relatively
simple pattern of penis size and pilaster proportion
shifts, but in the Marquesan species (table LIV) the
addition of a pustulose zone in the penis increased the
options for change. The two Planudonta show size,
pilaster length, and pustulose zone location variations,
while the Taipidon show a unique pattern of change.
On two different islands sympatric congeners have
diverged in penial structure by one species having the
pilasters broken up into a series of low bumps (figs.
138f, h; 139b, f).
The relatively few examples cited in these tables
represent all the situations in which the anatomy of
sympatric congeners could be studied. They have a
greater importance by demonstrating the extent and
ways in which these structures can be altered by
interspecific selection phenomena. They also suggest
that the size and shape variations seen in the penes of
the few Endodonta and Cookeconcha dissected during
this study (figs. 164, 165), none of which are sympatric,
do not have great systematic importance. Rather it is
probable that these variations hint at the extent of
sympatric diversity in the essentially unstudied Ha-
waiian endodontid fauna. Similarly, they suggest that
the wild variations seen in the terminal genitalia of
New Zealand and New Caledonian taxa have to be
interpreted in terms of such character displacement
reactions.
At the same time, a note of caution must be
injected here. Some of the outlined situations may be
oversimplified. In the species accounts of Libera
bursatella bursatella and L. b. orofensis reference is
made to differences between and within populations in
regard to penis size. Whether this is dimorphism,
sibling species, or an apparent reversal of character
displacement under conditions of exact sympatry is
unknown. The L. b. bursatella with generally longer
penes came from Station 863, where L. cookeana
(penis length 5.9 mm.) occurred, but not L. micra-
soma, with a penis length of 3.9-4.1 mm., which
occurred with L. b. bursatella (penis length 4.3-4.5
mm.) at Station 866. Since there are clear-cut pilaster
differences between the three species, the possible
tendency toward closer similarity in penial length with
sympatry of the different species is of very uncertain
significance. Further work on these problems will
depend upon new collecting efforts, since yet another
complication exists. At Station 863, there were 169 L.
b. bursatella and only one L. cookeana, while at
Station 866, there were 90 L. b. bursatella and six L.
micrasoma. The extent to which such disparate
numbers would affect character displacement is
unknown.
The Pacific Island Charopidae normally have a
verge or vergic papilla and sophisticated circular or
pocket-like stimulatory pads or pilasters. In the
absence of these structures (epiphallate Micronesian
genera), there is a combination of added muscular
sheaths to the penis and epiphallus, plus a radiation of
numerous fine lamellar pilasters from the epiphallic
pore into the penis interior, where they coalesce into
three large longitudinal pilasters.
Origin of the penial retractor muscle is yet
another variable feature in the Endodontidae. In 29 of
the 40 taxa in which this could be observed, the
muscle originates from the diaphragm. While in one
case the penial retractor is attached as low as the
middle of the pallial cavity (Aaadonta fuscozonata)
normally it attaches opposite the pallial cavity apex.
A. fuscozonata has a sharply increased whorl count in
comparison with other Aaadonta, so there may have
been a forward shift of the muscle. In Aaadonta
kinlochi and A. constricta, the attachment is just
below the apex. It is slightly above the apex in
Orangia cookei and Opanara areaensis, while in
82
SOLEM: ENDODONTOID LAND SNAILS
Minidonta hendersoni the penial retractor attaches
just at the point of stomach expansion.
This variability serves to indicate how gradual
apical shift of the penial retractor origin could lead to
the transfer of the muscle from the diaphragm to the
free muscle system, generally the columellar muscle.
This state is known in 11 taxa, including all dissected
Endodonta and Australdonta. Both Planudonta for
which the origin of the retractor muscle is known have
it coming from the columellar muscle. The same state
is found in both subspecies of Taipidon petricola, the
smallest species in its genus, although other Taipidon
have the more normal retractor muscle origin. In
Opanara duplicidentata the penial retractor attaches
to the tail fan just before this is joined by the buccal
retractors. In Nesodiscus fictus the penial retractor
TABLE LIT. - SYMPATRIC VARIABILITY IN PENIS SIZE
AND PILASTER PATTERNS IN RAPAN TAXA
Species
Penis length
in nun .
Opanara
bitridentata
2.65
duplicidentata
1.5
areaensis
2.65
megomphala
2.0-2.7
altiapica
1.8-2.1
Orangia
cookei
2.0-2.1
sporadic a
2.3
maituatensis
3.6
Ruatara
oparica
3.3
Rhysoconcha
1.6-1.9
Pilaster pattern
both equal
one split
one reduced
both equal
one greatly reduced
unequal, both high, one split
subequal, both widened, shorter
subequal, both split
only one corrugated, split basally
both equal
attaches partly to the columellar muscle and partly to
the diaphragm.
This shift of the penial retractor muscle origin has
no obvious correlatives, but does have a significant
result. Since the columellar muscle extends much
further apically than the diaphragm, which attenuates
as connective tissue at the level of the stomach, this
shift in origin permits lengthening of the penis (fig.
56). A long penis is not a prelude to this shift, since
Opanara duplicidentata, the only species in that
genus to show the change in penial retractor origin,
also has the smallest penis in the genus. In both
Planudonta and two of the three Endodonta, penis
length exceeds the shell diameter. In most other taxa
it is considerably less. Only Taipidon semimarsupialis
of the taxa with diaphragm origin of the penial
retractor has the penis longer than the shell diameter.
This probably is an accident caused by the secondarily
changed growth pattern (fig. 143e) associated with
brood-chamber formation in that species. In Libera
micrasoma shell diameter and penis length are
TABLE LIII. - SYMPATRIC VARIABILITY IN PENIS SIZE
AND PILASTER PATTERNS IN TAHITIAN SPECIES
Species
Mautodontha
zimmermani
aoraiensis
Penis length
in mm.
Libera
micrasoma
b_. bursatella
cookeana
3.9-1*.!
U.3-U.5
5.9
Pilaster pattern
both equal
both equal
equal , simple
subequal , folded
one greatly reduced and
only on lower half of penis
TABLE LIV. - SYMPATRIC VARIABILITY IN PENIS SIZE
AND PILASTER PATTERNS IN MARQUESAN SPECIES
Species
Planudonta
intermedia
concava
Taipidon
centadentata
semimarsupialis
fragila
varidentata
Island
N
N
N
N
H
H
Penis length
in mm.
U.6
6.0
U.3
*. 9-5. 3
1.5
2.5
Pilaster pattern
small pilaster shorter,
pustulose zone lower in penis
small pilaster longer ,
pustulose zone more medial
split into bumps
unequal, high
unequal, high
split into bumps
N=Nukuhiva ; H=Hivaoa
PATTERNS OF MORPHOLOGICAL VARIATION
83
virtually identical. This is another brood chamber
situation.
In the Pacific Island Charopidae, the penial
retractor muscle inserts in a U-shaped fan on the
penis-epiphallus junction, on the head of the highly
complex epiphallus in the epiphallate Micronesian
genera, or on the head of the penis with the vas
deferens passing through the muscle in the third major
group of taxa.
The atrium (Y) is formed by the union of the
penis and terminal female genitalia (spermatheca,
vagina, free oviduct) to form a common channel to the
gonopore. Generally this is quite short, but in
Australdonta, Endodonta, and Aaadonta the atrium
is noticeably longer than normal, and in Minidonta
hendersoni, Taipidon varidentata, Planudonta con-
cava, and Nesophila tiara there is some lengthening
present compared with related taxa.
The above discussion of variations in the male
terminal genitalia can be summarized rather simply.
The vas deferens normally enters the penis laterally
through a simple pore, but in a few taxa more apical
entry is obtained. In one lineage, the Thaumatodon-
Aaadonta sequence, experimentation in development
of a penial epiphallus has been accompanied by
adoption of a valvular vas deferens entrance. In other
groups accessory tissue on the penis apex may serve an
epiphallic secretory function. The penis itself normally
has two longitudinal pilasters that may be low and
rounded, elevated and rounded, or very high and
lamellate. The pilasters may be equal in size or
sharply different, frequently depending on character
displacement interactions with sympatric congeners.
Major changes in Ruatara and two species of Taipidon
apparently result from this phenomenon. The penial
retractor muscle normally attaches to the diaphragm,
but can shift to the columellar muscle just above the
point where it is formed by union of the tail fan and
buccal retractors. A few genera show a significantly
elongated atrium, but most are short. The only
additive structures to the terminal male genitalia are
the pustulose zone found in the two Marquesan
genera: the valvular entrance of the vas deferens seen
in Thaumatodon, Aaadonta, and Priceconcha', and
the added tissue on the penis apex in Orangia,
Planudonta, many Taipidon, and some Opanara. The
other variations are quite minor modifications on a
unitary theme.
The Charopidae present a considerable contrast in
having an epiphallus originating from the vas deferens,
frequently a verge or vergic papilla, usually quite
complex and extensive pilaster arrangements in the
penis, often a very short penial retractor muscle that
inserts in quite a different fashion, and radical changes
in structure from group to group of the Pacific Island
taxa. Even the isolated penis would be sufficient to
indicate if a species belonged to the Endodontidae or
Charopidae, and often what genus or group of genera.
TERMINAL FEMALE GENITALIA - This
includes the post-uterine tubes, which are quite simple
and uncomplicated in the Endodontidae. The normal
pattern in land snails is for a thin-walled or muscular
tube to lead from the glandular uterine section of the
spermoviduct (if it shows a fused prostate-uterus) or
uterus for a short-to-medium distance. This is the free
oviduct (UV) and may be highly complex internally. It
is joined by the shaft of the spermatheca (S). The
combined tubes then extend forward to the atrium as
the vagina (V). In the Charopidae, for example, the
vagina may have almost as complicated a set of
pilasters as is found in the penis of that group, the
lower part of the spermathecal shaft may be enor-
mously swollen because of high pilasters extending
from the upper vagina, with the free oviduct opening
reduced to a narrow pore. The upper portion of the
free oviduct may have thick walls and be glandular in
nature, while the spermathecal shaft narrows to a thin
tube at the anterior end of the uterus, ascending along
the latter to a typically ovate expanded head. There
are numerous characters to use in systematic analysis,
and in taxa from New Zealand and Australia it seems
probable that the terminal female genitalia, as well as
the male genitalia, are involved in species recognition.
The Endodontidae, in contrast, have extremely
simple terminal female genitalia. A thin tube, without
prominent internal features, extends from the lower
section of the uterus to the atrium. It may be joined
by the spermathecal shaft (which is a uniformly
undifferentiated tube for its entire length) slightly to
moderately above the atrium, thus technically forming
a short vagina, or the spermatheca may insert on the
penioviducal angle, effectively entering the atrium
directly. In a few taxa, mainly the Thaumatodon-
Aaadonta assemblage, the spermatheca actually in-
serts on the penis itself, slightly above the atrium.
Regardless of where the spermatheca inserts, there are
no indications of structural differentiation in the
female tubes, nor even recognizable pilasters. They are
extremely simple ducts.
The pattern of spermathecal insertion is primarily
phyletic, with some convergences having occurred.
Penial insertion of the spermatheca (fig. 48a) is
characteristic of Thaumatodon, Aaadonta, and Price-
concha. The entrance is on the inside of the
penioviducal angle, distinctly above the point where
the penis separates from the atrium. There is no
special internal structure evident. In Rhysoconcha (fig.
64g) the same pattern is seen. Atrial (fig. 48b) insertion
of the spermatheca is normal in Minidonta, Austral-
donta, Orangia, Libera, Taipidon, Planudonta, all
Opanara except two, and Mautodontha aoraiensis.
Oviducal insertion (fig. 48c) occurs in Nesodiscus,
Nesophila, Cookeconcha, Endodonta, Ruatara, Opan-
ara depasoapicata, O. bitridentata, and Mau-
todontha zimmermani. The distance shift is not great
and I question whether this makes any functional
significance. Atrial and oviducal insertion occurs in
84
SOLEM: ENDODONTOID LAND SNAILS
FIG. 48. Spermathecal insertion patterns: a. penial insertion
(based on Thaumatodon euaennin); b, atrial insertion (based on
Libera coakeana); c, oviducal insertion (based on Endodonta fricki).
(CK)
both Mautodontha and Opanara, but otherwise there
is phyletic correlation.
In all Endodontidae and Charopidae the sperma-
thecal head extends past the pallial cavity apex. It is
an elongately bulbous structure that lies next to the
base of the albumen gland (fig. 49a) along the parietal
wall and then next to the kidney base. It is sometimes
lost during dissection of charopids because the artery
passes over the spermathecal stalk to bind it into the
apical viscera, but in all Endodontidae this appears to
be free of this loop and thus dissects out easily. In
order to show the relationships of this organ, Endo-
donta fricki was drawn with the organs pulled slightly
apart. The perspective in this drawing (fig. 163d) might
be interpreted as indicating that the spermathecal
head lies below the pallial cavity apex, but this is an
artifact. Many spermathecae seen in this study
contained compact masses of sperm, but these were
not enclosed in a membrane. There is no evidence of
any spermatophore formation.
The above discussion of the genital system surveys
patterns of variation and features observable after
teasing apart the separate organs. It is useful to have
one drawing in which the organs are portrayed as they
are dissected out in early stages of study. Figure 49a
attempts to show the just-excised genitalia. The
material of Taipidon petricola decora was received for
study long after the main systematic section had been
completed. Hence it was decided to draw this showing
the typical position of the organs when first dissected
out, rather than as separated, to show all origins and
insertions. This permits showing one apparently quite
characteristic feature of the family. The shaft of the
spermatheca (S) lies first on top of the free oviduct,
then it sits directly on top of the vas deferens (VD)
and prostatic duct for about the lower half of the
prostate (DG). About the middle of the prostate, the
spermathecal shaft shifts in position to lie on top of
the prostatic acini and parallels the prostatic duct for
the upper third. This is the typical position for the
spermathecal shaft. The penis (P) has been shifted
laterally in this view and is unusual primarily for the
very low entrance of the vas deferens.
The above account concludes discussion of the
structural and topographic variations seen in the
genital anatomy of the Endodontidae. The differences
from the Charopidae are substantial and obvious if
even a fragmentary part of the genitalia is available.
These are summarized in Tables LVIII, LIX following
discussion of the other organ systems. Discussions of
some size correlated variations in anatomical
proportions are deferred, since several organ systems
are involved.
Pallial complex
In the Endodontidae this area shows a simple and
relatively uniform structural pattern, whose variations
are mostly correlated with size, whorl count, and
features of the palatal barriers. The typical
configuration is shown in Figure 49c. A more detailed
view is presented in Figure 195a. The most significant
features for phylogeay are the weakly bilobed kidney
(K) that reaches the hindgut (HG), the short reflexed
ureter (KD) that opens in a ureteric pore (KX) just at
the anterior tip of the rectal kidney arm, the simple
pulmonary vein (HV), and the variable pattern of a
mantle gland extension onto the pallial roof being
present (fig. 171e) or absent (fig. 49c). The total
PATTERNS OF MORPHOLOGICAL VARIATION
85
absence of any secondary ureter or urinary groove
leading from the ureteric pore (KX) to the
pneumostome is a feature of major phyletic impor-
tance (p. 103).
The functional significance of this is that ex-
cretory products must exit onto the pallial roof
surface. Water must then be used to flush out the
waste products. In the typical sigmurethrans there is
either a highly vascularized channel (many Bulimu-
lidae and other holopodopid taxa) or a closed secon-
dary ureter (Limacacea, Camaenacea, Helicacea)
through which the excretory products pass. This
divergence in the Sigmurethra was pointed out by H.
B. Baker (1962a; 1963, p. 220). The secondary ureter
seems to function primarily in water resorption.
Elsewhere I (Solem, 1974) have postulated that the
evolution of a secondary ureter was a necessary
preadaptation to the evolution of land slugs from
shelled ancestors. The exact level of classification
required to recognize the third type of structure seen
in the Endodontidae, a closed primary ureter, but no
trace of any secondary groove or tube, cannot be
considered here.
It is quite probable that the difference in median
mean whorl count between the Endodontidae (5'/2+)
and Charopidae (4'/8— ) relates to the fact that the
former lacks a ureter, and thus needs a greater pallial
cavity area for holding a water reservoir (Blinn, 1964)
than does the Charopidae in which there is a
secondary ureter present. The only charopid known to
me that may lack a secondary ureter is the Tasmanian
species Planilaoma luckmanii (Brazier, 1877). The
material available of this species was very limited and
this observation (Solem, unpublished) needs to be
confirmed by more dissections. To date, this is the
only Indo- Pacific taxon seen that might be in any way
transitional from the pallial cavity states of the
Endodontidae to the Charopidae.
The normal pattern in the Charopidae is for an
evenly bilobed kidney (secondarily altered with accen-
tuation of either rectal or pericardial arms in different
taxa); a complete secondary ureter opening lateral to
the anus at the pneumostome; only very rarely (in
Micronesian and Melanesian, but not New Zealand
taxa) any mantle gland invasion of the pallial roof; the
rectal kidney arm extensively overlapping the hindgut
(often both dorsally and ventrally); and the heart
much more deeply indenting the kidney. The differ-
ence of the secondary ureter in the Charopidae is the
fundamental distinction. This means that even the
smallest anterior fragment of the pallial cavity is
sufficient to decide to which family the species belongs
on the basis of ureter presence (Charopidae) or absence
(Endodontidae) by the hindgut just inside the
pneumostome.
Variation in the pallial region concerns the
presence or absence of a glandular extension from the
mantle collar onto the pallial roof, the relative length
FIG. 49. Anatomy of Taipidon petricola decora. North side of
Vaituha Valley, 600 ft. elevation, Eiao, Marquesas. BMNH: a,
genitalia; b, interior of penis; c, pallial structures. Scales lines equal
1 mm. (CK). (See Appendix for explanation of abbreviations.)
and prominence of the kidney arms, and the actual
length of the cavity itself. The correlatives of these
changes, which recur sporadically throughout the
family, are not strong. The mantle collar extension
involves shifting of some glandular materials from the
collar itself posteriorly onto the pallial roof. The
thickness and obvious nature of the extension varies
rather widely, perhaps indicative of the stage in
glandular activity. This area presumably is involved in
the secretion and resorption of the palatal barriers. In
swollen state this could be indicative of recent
posterior barrier resorption, while in reduced state this
could be indicative of recent deposition of calcareous
material. Thus variation from individual to individual
could be expected. Because specimens had been
preserved mostly for long periods in alcohol of
uncertain strength and acidity, retention of calcium
residue in the glandular areas could not be depended
on and no tests for calcium were made. The mantle
86
SOLEM: ENDODONTOID LAND SNAILS
collar extensions were obvious in Australdonta de-
gagei, but not in A. raivavaeana; prominent in
Endodonta (fig. 163e) and Nesodiscus (fig. 154b);
prominent (fig. 171e) to absent (fig. 172e) in the
illustrated Libera (but clearly present in other
examples of Libera fratercula); present in most
Thaumatodon and all Aaadonta', and also seen in
Taipidon semimarsupialis. No traces of any pallial
roof glands were seen in specimens of Minidonta,
Cookeconcha, Opanara, Rhysoconcha, Orangia, the
other Taipidon, Planudonta, or Nesophila. Many of
those taxa with mantle roof gland extensions have
long and/or deeply recessed barriers (10 taxa). The
shift in mantle gland tissue under these conditions has
obvious value in permitting barrier resorption and
deposition activities with less complete animal retrac-
tion. Taipidon semimarsupialis and Thaumatodon
euaensis, in contrast, have short (one-eighth whorl)
barriers at the lip edge, the two Australdonta and
Endodonta lamellosa have equally short, slightly
recessed barriers, while the other two Endodonta have
moderately recessed, short barriers. Taxa with such
long barriers as Priceconcha (Solem, 1973d, p. 23)
show no trace of mantle gland extension. While 10
taxa with mantle gland extensions have extra long
and/or deeply recessed barriers, six do not, and some
taxa with deeply recessed or very long barriers lack
any trace of such an extension.
The variation in kidney width was not quantified,
but obviously varies, as can be seen by comparing the
very narrow, folded kidney of Libera b. bursatella (fig.
171d) with the far broader kidney of Aaadonta c.
constricta (fig. 199a) and the average kidney shape of
Thaumatodon euaensis (fig. 195a) or Taipidon petri-
cola decora (fig. 49c). The broadened kidney in
Aaadonta probably correlates with the comparatively
great palatal wall distance from the parietal-palatal
margin to the high second palatal barrier (fig. 203b),
while in T. euaensis (fig. 194b) and T. petricola decora
(fig. 140c) this same zone is distinctly narrower.
Barriers would not be a factor in Libera b. bursatella,
but the extreme deflection of the last few whorls (fig.
174a) has shortened the upper palatal wall (that
portion above the weak peripheral keel) quite dras-
tically. The extreme narrowing of the kidney in this
species can be a byproduct of this space change.
Relative length of the kidney lobes was scored as
the rectal lobe (that next to the hindgut) being
distinctly less than half the length of the pericardial
lobe (that next to the heart), or essentially half the
length. Often the difference is quite striking, as in
Aaadonta constricta and A. fuscozonata (figs. 199a, f),
even though both of these are scored as having the
"short" rectal lobe. The longer type rectal lobe is
found in a variety of taxa, such as Nesodiscus (fig.
154b) and various Libera (figs. 171d; 172e) with
elongated pallial cavities and high whorl counts, but
also in Opanara, Ruatara, and some Cookeconcha
with typical or possibly slightly reduced whorl counts.
HG
FIG. 50. Pallial cavity length variation, based on the typical (a)
and an elongated (b) condition. (See Appendix for explanation of
abbreviations.)
The relative position of the lobes can be altered by
retraction of the body resulting in pushing the hindgut
rectal lobe further apically than the pericardial lobe,
thus distorting the apparent length relationship. No
intrinsic significance can be attached to this variation.
The major variation in appearance and size is
change in length of the pallial cavity. This could be
measured in 35 taxa and usually is expressed to the
nearest one-eighth whorl. Flattened length measure-
ments are subject to greater inaccuracy and give a less
functionally correlated indication of length. The most
frequent states were between five-eighths and three-
fourths of a whorl, found in a total of 19 taxa (fig.
50a). Variation within a population was tested on a
sample of Libera f. fratercula from Motutapu Island
PATTERNS OF MORPHOLOGICAL VARIATION
87
off Rarotonga (FMNH 152742). Whorl counts of the
shells ranged from 61A to 7, with pallial cavity length
varying from five-eighths to slightly less than a full
whorl. Part of the variation was an artifact of
contraction. Specimens deeply retracted into the shell
had a cavity length at or near the high range of the
variation. By pulling back up to a quarter whorl from
the aperture, the linear length needed to occupy a full
whorl was reduced. This makes the increased
length an artifact of spiral distance rather than a
change in actual measurement. This artifact in the
data prevented meaningful statistical treatment. The
median pallial cavity length in the Libera sample was
three-fourths whorl.
Allowing for this variability, the significant depar-
tures from the average pallial cavity length in adult
specimens were comparatively few. Planudonta con-
cava had a three-eighths whorl-long cavity, despite the
shell reaching a 6% whorl count, which is significantly
over the family median of 5'/2 + . Presumably this
involved no proportionate change in pallial cavity
length, despite the raised whorl count. A number of
species had one-half whorl pallial cavities — Minidonta
hendersoni, Mautodontha zimmermani, Cookeconcha
jugosus, Opanara areaensis densa, Thaumatodon
spirrhymatum, T. hystricelloides, and Aaadonta con-
stricta. These agree in that the dissected specimens
have 5 to 5% whorls, with a mean of 5Vi + . This
compares with a mean of 5%+ for those species with
average pallial cavity lengths. Elongation of the pallial
cavity (fig. 50b) is to essentially one whorl in Taipidon
semimarsupialis, Nesodiscus fictus, and Endodonta
fricki; IVs whorls in Aaadonta f. fuscozonata', and
between 11A and l'/2 whorls in Libera micrasoma and
L. b. bursatella. These are either brood-chamber taxa
or the species with the highest whorl counts in their
genus, averaging one-fourth (Aaadonta) to seven-
eighths (Nesodiscus) whorl more than any other
species in their genera. It is reasonable to look upon
these species as showing proportionate elongation of
the pallial cavity as the whorl count increased. The
dissected specimens of these taxa had a mean whorl
count of 6% -, substantially above the other groups.
The general elongation of the cavity correlates with
the extremely shortened rectal lobes seen in Aaadonta
fuscozonata (fig. 199f), Taipidon semimarsupialis (fig.
139c), and Endodonta fricki (fig. 163e). It is not the
only correlative, since in Nesophila tiara (fig. 165c)
the rectal lobe is virtually absent, possibly as a result
of the dramatic overall size increment to over 11 mm.
shell diameter in this species. The much larger whorl
cross-section would provide adequate kidney volume
space along the upper palatal wall without the
thickness of the lobes seen in Libera (fig. 171d).
Basically the variations in kidney size, shape, and
pallial cavity length should be looked on as represent-
ing space compromises. Presumably there is an
effective kidney-volume/body-volume ratio that has to
be maintained. The changes in shell growth that
alter the palatal wall barrier configurations result in
adjustment as to the kidney shape and lobe lengths.
The available material did not lend itself to comparing
foot length, shell whorl count, and pallial cavity
length to see if the increase of length in the pallial
cavity might be required to provide extra space for foot
withdrawal. There is no question but that most of the
length increase comes through extension of the relative
area occupied by the respiratory surface between the
anterior tip of the kidney and the pneumostome (see,
for example, fig. 199a, f comparing one-half whorl and
\Vs whorl pallial roofs, respectively).
Other features in the pallial complex show no
significant variations in those taxa dissected. The
heart (H) generally is slightly more than half the
length of the kidney (K) and lies almost exactly
parallel to the hindgut (HG). The hindgut extends
only slightly apicad of the kidney base before
departing from the parietal-palatal margin (fig. 163d).
It then shifts onto the palatal wall and continues
apically past the stomach expansion. In most dissected
specimens there are at least traces of the mantle
retractor muscle (fig. 199a, MD) present, but this
feature has been omitted from most drawings.
In summary, the pallial complex in the Endodon-
tidae is quite uniform in structure and differs
significantly from that of the Charopidae in its lack of
any secondary ureter. Changes in pallial cavity length
correlate partly with whorl count alterations. Changes
in the kidney shape and proportions correlate with
changes in the upper palatal wall proportions. While
the pallial complex has high information content as to
family affinity, it yields little information on relation-
ships within the family.
Digestive system
Descriptions and figures (figs. 163, 164) of Endo-
donta fricki serve to illustrate the basic structures of
the digestive tract and associated glands. The buccal
mass (fig. 164e, B) is uniform in shape throughout the
family and has a very small generative sac visible
posteriorly. Often the buccal ganglion (BGN) remains
attached after dissecting out the buccal mass and
muscles. The two salivary glands (OG) touch above
the esophagus (BE) but are not united. Their ducts
(OGD) enter the top of the buccal mass on either side
of the esophagus. The buccal retractor muscles (BR)
insert in a U-shaped fan on the buccal mass base. The
esophagus is another "space saving" organ, since it
passes from the buccal mass to past the pallial cavity
apex, preserving the space function of the pallial cavity
for retraction of the head and foot. Expansion of the
digestive tube into a stomach (fig. 164f, IZ) starts
perhaps one-eighth whorl above the pallial cavity apex
and is completed one-eighth whorl later. The stomach
extends from one-half to more than one whorl apically,
then reflects into the narrow intestine (I) that passes
forward into the typical complicated looping pattern
between stomach and pallial cavity apex that is
characteristic of pulmonates. One loop of the intestine
f
FIG. 51. Radular teeth of Libera fratercula rarotongensis. Station R15, east of Avarua, Rarotonga, Cook Islands. FMNH 152744: a, central
and early laterals viewed from low posterior angle at 1,850 X; b, anterior view of early laterals at 4,225 X; c, inside view of right laterals at
5,150x ; d, outside view of right laterals at 5,375x showing interrow support; e, lateromarginal transition viewed from left posterior at 2,150x ; f,
detail of marginal teeth at 5,325 x.
88
FIG. 52. Radular teeth of Taipidon petricola decora. North side of Vaituha Valley, 600 ft. elevation, Eiao, Marquesas. BMNH: a, partial
row of teeth viewed from anterior front at 1.275X; b, central and first lateral teeth viewed from anterior side at 3,075 X; c, worn mid-marginal
teeth from right side of radula at 5,350 x ; d, worn lateral teeth from right side of radula at 3,435 x ; e, late marginal teeth at 5,215 X .
89
90
SOLEM: ENDODONTOID LAND SNAILS
projects forward under the kidney base, indenting
rather deeply the inner surface of the kidney. The
position of the hindgut has been described previously.
Variations in esophagus length correlate exactly
with pallial cavity length. Variations in stomach
length are a factor of how many whorls of the shell are
actually occupied by the soft parts as adults (pp. 94-
95), plus changes in the cross-sectional areas of the
whorls. With elongation of the soft parts and narrow-
ing of the whorls, the stomach will be longer.
Shortening of the soft parts and increase in the cross-
sectional whorl area will shorten the stomach. Ex-
treme contraction of the animal when the stomach is
empty will give the illusion of a shorter stomach, since
the severely compacted soft parts will collapse the
early section of the stomach to permit maximum
withdrawal.
Only in the radula and jaw are there significant
changes in size and structure. Almost all of this work
was done prior to the late 1960's general availability of
the scanning electron microscope. Hence the data
presented here is far less satisfactory than could be
accomplished with the same material today. Because
the radula is extremely tiny and the individual teeth
are in the 6-16 fj. size range, optical observation was
quite difficult. It was not possible to observe outer
marginal teeth in the vast majority of species due to
mounting problems. More than in any other group of
snails that I've studied, the marginal teeth of the
radula fold under or fragment off during handling.
With the size of the central tooth ranging from 4 X 6/1
in Taipidon centadentata to 13 X 16 JLI in Ruatara
oparica reductidenta, observations on other than the
point of transition to marginal teeth (indicated by
endoconal appearance and tooth-size reduction) and
basic cusp patterns were not possible. Recently I have
been able to study the radular teeth of Thaumatodon
spirrhymatum and Priceconcha tuvuthaensis (Solem,
1973d), Libera fratercula rarotongensis (fig. 51),
Taipidon petricola decora (fig. 52), Endodonta fricki
(fig. 53), and Thaumatodon hystricelloides (fig. 54)
using the scanning electron microscope. This has
added considerable information.
The basic pattern is that of a tricuspid central
tooth (figs. 51a; 52b) with the two ectocones quite
small compared with the mesocone, and the mesocone
itself often slightly shorter than the mesocone on the
flanking first lateral teeth. On either side are generally
five to six bicuspid laterals (figs. 51b, c) in which the
ectocone is slightly less than half to only one-third the
mesoconal length. There is no trace of an endocone,
except in teratological rows (fig. 54b). The transition
to marginal teeth generally occurs over a three-tooth
spread, involving size reduction of the tooth, shorten-
ing of the basal plate, appearance of an endocone,
partial reduction in size of the mesocone, and increase
in relative ectoconal prominence. The marginal teeth,
which usually were lost in preparation, tend to more
or less multicusped ectocone, smaller size, widened
FlG. 53. Radular teeth of Endodonta fricki (Pfeiffer). Makalea,
Waianae Mts., Oahu, Hawaii. FMNH 53042: a, early marginal teeth
at 1,090 X; b, lateral teeth from left side of radula at 1,200 X (note
deformed row with endocone at lower area). Extracted from a dried
specimen and incompletely cleaned.
form, and shortened length. Since the transition from
lateral to marginal teeth occurs over several teeth,
observers may count them differently. Cooke (1928)
reported four laterals in Endodonta lamellosa, five in
E. marsupialis, and seven or nine in E. fricki, with,
respectively, 16-19, 17-20, and 12-14 marginals. These
differ from my observations slightly. In the few cases
Fir,. 54. Radular teeth of Thaumatodon hystricelloides (Mousson). Station 19, Lake Lanuto'o, Upolu, Western Samoa. FMNH 153130: a,
worn laterals from left side of radula at 1.795X ; b, lateromarginal transition zone from right side of radula showing a deformed longitudinal row
(upper left) at 1,265 X; c, early unworn laterals from right posterior at 5.975X; d, early marginals from same area of radula at 6.325X; e, late
marginals from right side of radula at 1.240X; f, late marginals in detail at 3,175x. Figures b, d, e, /courtesy of Engis Equipment Company
demonstration of a Cambridge scanning electron microscope.
91
92
SOLEM: ENDODONTOID LAND SNAILS
where complete or nearly complete marginal fields
were mounted successfully, there were 9-13 marginals,
the number increasing to as many as 20 in Endodonta
marsupialis, for example. The number of laterals
increased to seven to eight in the three Thaumatodon,
Nesophila tiara, Planudonta subplanula, Taipidon
fragila, and T. varidentata. Cookeconcha hystricellus,
C. hystrix, and Planudonta concava had 9-10 laterals;
Cookeconcha jugosus and Taipidon semimarsupialis
had 11-14 laterals; and in Taipidon centadentata there
were 22-23 laterals. The increase in laterals in T.
semimarsupialis was accompanied by an increase in
marginals to 16-17 and a decrease in size of the teeth,
as measured by the central tooth, to only 4 X 6 n,
compared with the 8 X 10 ju in most other Taipidon.
This change in number of lateral teeth is not size
correlated, but is phyletically limited to Cookeconcha
and the Taipidon- Planudonta sequence.
The number of tooth rows ranged from 80 to 115
in the few species for which this could be tallied. The
total number of radular teeth varied from perhaps a
low of 2,700 in many Opanara to a maximum of 8,100
in T. semimarsupialis. Most of the species have about
3,000-4,000 in denticles. This is far below the typical
pattern seen in zonitoid taxa such as the Pacific Island
Microcystinae, Helicarioninae, Euconulinae, and
Trochomorphidae, where only 8 of 169 taxa for
which data are available in H. B. Baker (1938b, 1940,
1941) had radular tooth counts of under 6,000. Mean
tooth counts for these family level taxa were,
respectively, 14,900, 28,500, 13,450, and 11,750 teeth per
radula. In the New Zealand typical Charopidae, using
data from Suter (1913), total tooth numbers average
only 3,175, while the modified "flammulinids" average
5,676, although ranging from 2,300 to 9,380 teeth. The
possible significance of this is discussed below (pp. 104-
105).
The approximate size of the central tooth was
measured for each species using an optical micrometer
and a Leitz Ortholux microscope with phase-contrast
illumination. In Cookeconcha and Orangia, for ex-
ample, the teeth were narrow and elongated, measur-
ing, respectively, 6-8 X 14 n and 6-8 X 10-13 /i. The
largest teeth were seen in Endodonta (13 ju square)
and Ruatara (13 X 14-16 /x). The smallest were in
Opanara fosbergi (5 X 8 n) and Taipidon centaden-
tata (4x6 ju). None of these variations show obvious
shell-size correlation. Phyletic lineages are not in-
volved as Cookeconcha has elongate denticles and
those of its descendent genus Endodonta are virtually
square. On Rapa, Orangia has elongated denticles;
those of Ruatara are very large and squarish; and
Opanara has variable-sized denticles.
Optical study of the Rapan species suggested yet
another pattern of variation. In Opanara, Ruatara,
and Orangia, by the fourth lateral there is a marked
inward curve of the mesocone. By the eighth or ninth
tooth from the center, there is a distinct endocone and
the mesocone is like that of the typical species.
Previously it was much larger. After the sixth or
seventh tooth, the size decreases rapidly to typical
multicuspid marginals. In Rhysoconcha, the marginals
appear to be the same size as in the other taxa, but the
central (6 X 8 n) and laterals appear noticeably
smaller than in most other Rapan species. Unfortu-
nately, their size was so small and the mounts so poor
that I am uncertain as to the exact cusp structure in
comparison with the larger species. The decrease in
size for mid-radular teeth in Rhysoconcha, elongation
in Orangia, variability in Opanara, and large square
shape in Ruatara possibly indicate specialization in
feeding or substrate factors. The above material had
been mounted for optical study and returned before I
had access to a scanning electron microscope. It was
not practical to reopen this phase of the study.
Scanning electron microscope observations have
been made on six species of Endodontidae (Solem,
1973d; this paper), plus 39 species of Charopidae and
Punctidae from Australia, New Zealand, New Cal-
edonia, and Lord Howe Island. Data about the
Endodontidae are summarized first.
As is typical of pulmonate radulae, the central
and lateral teeth show an interlocking device between
longitudinal teeth rows. The stressed cusp will receive
support from the basal plate in the next anterior row.
The existence of this inter-row support mechanism was
first reported in a variety of taxa (Solem, 1972a) and
the pattern of change in the Charopidae reviewed
subsequently (Solem, 1973a, pp. 166-167). The basal
plate of the central tooth in the Endodontidae, as
exemplified by Libera fratercula, has a raised lateral
ridge on each side of the basal plate (fig. 51a). In the
early laterals (figs. 51c, d) the flared lateral ridge is
restricted to the ectoconal (outer) side of the tooth
and functions to prevent lateral shifting of the teeth
under stress. The endoconal (inner) side (fig. 51a,
upper right) of the laterals has virtually no trace of
the support ridge. Exactly the same pattern is seen in
Taipidon (fig. 52d), Thaumatodon (fig. 54b; Solem,
1973d, figs. 6, 7), and Priceconcha (Solem, 1973d, figs.
13, 14).
The marginal teeth are characterized by basal
plates that are greatly reduced in length (but not
width), development of a medium to prominent
endocone, reduced mesocone, and often split ectocone.
The transitional area from laterals to marginals (figs.
51e; 52a; 54b; Solem, 1973d, fig. 8) is short. Apparently
there are significant differences in the pattern of
marginal tooth structure, but because of their small
size and the nature of these differences, only the few
species studied with the SEM can be discussed. In
Taipidon (figs. 52c, e) the cusp sits very low on the
basal plate, all cusps become narrow and elongated,
while the ectocone tends to become bicuspid. In Libera
(figs. 51e, f) the early marginal teeth sit much higher
on the basal plate, the ectocone tends more to
fragment, and the mesocone is not nearly so narrow.
PATTERNS OF MORPHOLOGICAL VARIATION
93
Thaumatodon hystricelloides (figs. 54d, e, f) has a very
long and dagger-shaped mesocone, a slender and much
shorter endocone, and initially a simple ectocone that
becomes highly fragmented on outer teeth (f). The
cusps of this species are elevated very high above the
extremely short basal plate. Only the first few
marginals were seen in T. spirrhymatum (Solem,
1973d, fig. 15), but these agree with the other
Thaumatodon. In Priceconcha tuvuthaensis (Solem,
1973d, figs. 8, 9) there is quite a different pattern of
ectoconal splitting on the marginals. Instead of
roughly coequal splitting of the ectocone, lateral knob-
like buds appear. The differences lie in the elevation of
the cusps above the basal plate, the method of
splitting for the ectocone, and the pattern of cusps on
the marginals. While these can be studied with the
SEM in angled view, they are below the level of
optical examination.
In summary, the Endodontidae have a relatively
uniform pattern of tricuspid central, bicuspid laterals
that number five to eight, only rarely increasing in
number, and somewhat more numerous tricuspid to
multicuspid marginal teeth. Tooth size and shape
varies within lineages, with changes in tooth numbers
basically occurring only in Cookeconcha and the
Marquesan Taipidon-Planudonta lineage. The latter
group shows the greatest amount of radular change,
with Planudonta concava, Taipidon semimarsupialis,
and T. centadentata showing progressively increased
tooth number, but progressively decreased tooth size
(table LV). The changes are not size correlated, since
the teeth of Nesophila tiara, whose mean shell
diameter of 11.29 mm. is vastly larger than the shell of
Cookeconcha jugosus (5.01 mm.) or C. hystricellus
(4.98 mm.), show no increase either in size or actual
numbers.
The typical radula found in the Charopidae
presents a number of obvious differences. In the vast
majority of species there is a tricuspid central tooth
that is markedly smaller than the flanking laterals,
which normally are tricuspid with equal-sized
endocone and ectocone. Generally, all laterals have a
narrow mesocone and large side cusps, but a few taxa
show significant modifications (based on unpublished
SEM observations). The New Zealand Allodiscus
dimorphus (Pfeiffer, 1853) has bicuspid laterals, but
typically multicuspid marginals; the New Zealand
Thalassohelix propinqua (Hutton, 1883) has bicuspid
laterals and unicuspid marginals; the New Zealand
Serpho kiwi (Gray, 1843) has a unicuspid central,
bicuspid laterals, and early marginals that approach
the helicarionid marginal structure; while on Lord
Howe Island the succineiform Mystivagor mastersi
(Brazier, 1876) (Solem, 1973a, fig. 6) has a peculiar
anterior supporting flare developed and Pseudocha-
ropa lidgbirdi (Etheridge, 1889) has unicuspid margin-
als. Apparently all of these modified taxa are partly-
to-completely arboreal in habitat, which probably
explains the selective pressure behind the
modifications. The marginals in the Chaopidae vary
widely in shape and form, much more than in the
Endodontidae.
Consideration of this variation is deferred. Stand-
ing in extreme contrast to both radular types are the
denticles in the Punctidae. They have a unique
pattern of very tiny lateromarginal undifferentiated
teeth in which there is a narrow, bicuspid tooth with
slender basal plate and evenly curved anterior that
rises to the cusps, which point essentially directly
forward and have extremely tiny accessory cusps on
each side of the tooth and then between the two main
cusps. This peculiar pattern was detected by H. B.
Baker many years ago (Pilsbry, 1948, p. 642, fig. 349,
TABLE LV. - RADULAR TOOTH SIZE AND NUMBERS IN NESOPHILA,
COOKECOHCHA, TAIPIDON, AND PLANUDONTA
Species
Cookeconcha
hystricellus
Hesophila
tiara
Taipidon
p_. petricola
varidentata
fragila
semimarsupialis
centadentata
Planudonta
Tooth numbers
Laterals Marginals
9-10
lit
subplanula
concava
6
1
7-8
13-15
22-23
10-11
10-11
8+4+
8+++
13
9-10
10-13
16-17
10
7+++
Central tooth size
in microns
8 X 13-11*
6 X lit
9-10 x lU
7-8 x 8
8 X 10
8 X 10-11
6-8 x 8
l* X 6
6 X 8-10
8 x 10
94
SOLEM: ENDODONTOID LAND SNAILS
d), but is much more easily interpreted with scanning
electron microscope observations.
In typically unmodified endodontoid taxa, in-
spection of the radular lateral teeth is quite sufficient
to establish family affinities. They are bicuspid in the
Endodontidae, bicuspid but very differently curved
and with accessory microcusps in the Punctidae, and
tricuspid in the Charopidae. This presents one of the
clearest diagnostic features in terrestrial species, but is
subject to at least partial convergence in the arboreal
Charopidae.
TABLE LVI. - SHELL SIZE AND JAW STRUCTURE IN THE ENDODONTIDAE
State
Separated
square plates
Separated
elongated plates
Central plates
partly fused
All plates fused
. .' • er
of taxa
1
16
9
1
Shell diameter in mm.
2.93
3.TU±0.19 (2.5U-5.79)
5.75±0.50 (U. 23-8. 99)
11.29
Jaw structure in the Endodontidae varies with
size (table LVI). Typically (fig. 125g), the jaw consists
of many separate, elongated chitinous plates. This is
the pattern found in Opanara, Australdonta, Thau-
matodon, most Aaadonta, Planudonta concava,
Taipidon varidentata, and T. fragila. One species,
Aaadonta fuscozonata, has the plates nearly square in
shape. In a number of species, all Cookeconcha,
Endodonta, Nesodiscus, Planudonta subplanula,
Taipidon centadentata, and T. semimarsupialis, the
central plates of the jaw are at least partly fused,
although the plates on either side are clearly separated
from each other and retain the typical elongated
shape. Finally, in Nesophila tiara the jaw plates are
completely fused together. The correlation of increas-
ing jaw plate fusion with increasing size is obvious
(table LVI). In the Charopidae there is a basically
similar pattern of separated and elongated plates, with
partial fusion occurring first in the center of the jaw,
while in the Punctidae only the pattern of small,
clearly separated plates has been observed. Presum-
ably, this correlates with the small size of most
punctids.
Variations in the jaw structure, stomach length,
esophageal length, and possibly the number of margin-
al teeth correlate with size and whorl count factors.
Radular cusp size and shape variations cannot be
studied effectively by optical viewing, but only a few
taxa could be examined with the scanning electron
microscope.
Free muscle system
In all the dissected species, the right ommatopho-
ral retractor passed through the penioviducal angle,
while the right rhinophoral retractor passed outside
the angle. Fusion of the tentacular retractors, buccal
retractors and tail fan to form the columellar retractor
occurs at slightly different relative positions, correlat-
ing mainly with the length of the pallial cavity. The
pattern of free muscle fusions detailed for Endodonta
fricki and Nesophila tiara are typical. For most taxa,
only obvious differences from this pattern have been
annotated in the text. The origin of the columellar
retractor muscle has been discussed above.
Nervous system
In both Thaumatodon hys trice lloides and Libera
fratercula fratercula the penis is enervated from the
right cerebral ganglion. The ganglia in the dissected
Endodontidae are proportionately much smaller than
those in such families as the Tornatellinidae and are
much more heavily encased in sheets of connective
tissue. Because of the limited material and reduced
prominence of the structures, no attempt was made to
study details of the nervous system.
External body features
Throughout the Endodontidae, the body color is a
pale yellow white, with the eye spots and early portion
of the ommatophoral retractors providing the only
touch of darker color. This contrasts immediately with
those Charopidae living in arboreal or semi-arboreal
habitats. The tentacles, head, neck, and often the tail
of these species have scattered to heavy greyish pig-
mentation, although the ground strata species have
the same yellow-white body color seen in the
Endodontidae.
The foot in the Endodontidae is universally long
and slender, bluntly rounded posteriorly and truncated
anteriorly, without longitudinal or transverse grooving.
There is a prominent pedal and noticeably weaker
suprapedal groove (FS) on the sides of the foot that
unite above the tail, but there is no development of a
caudal foss or caudal horn (fig. 163a). The slime
network is weakly defined. Without exception the
gonopore is a short vertical slit located below the right
ommatophore and both above and slightly behind the
right rhinophore. The mantle collar (fig. 163b) is
without developed lobes or exterior protrusions, al-
though several species show an extension of glandular
materials onto the pallial cavity roof (pp. 84-85).
In the Pacific Island Charopidae the above
descriptions apply, but in the extralimital taxa there
are major variations. Several New Caledonian taxa, for
example, develop a "pseudo-operculum" on the tail
(Solem, unpublished], and in many arboreal and
semi-arboreal taxa from New Zealand there is a weak
to very prominent caudal horn developed (see Climo,
1969a for references and pp. 105-106 of this monograph
for a review of the controversy concerning the
systematic value of this feature).
Patterns of elongation
As outlined below (pp. 113-114), one of the
repetitive trends within the Endodontidae is for whorl
count and size increase to the "Nesodiscus" and
"brood chamber" levels of specialization. While this
involves some elongation of the soft parts, a much
PATTERNS OF MORPHOLOGICAL VARIATION
95
more typical pattern is for the animal to withdraw in
part from the upper whorl of the shells. In groups such
as the land prosobranch family Pomatiasidae, the
pulmonate Urocoptidae, and such subulinids as Ru-
mina decollata (Linne), the early whorls will be
evacuated by the animal which seals off the upper
whorls by a thick calcareous plug. The early whorls
usually break off. This reduces shell length highly
effectively with cylindrical coiling patterns, but is not
an option open to planulate or heliciform taxa. Where
these species show a great increase in whorl count over
"typical" taxa, such as in the trochomorphid Coxia m.
macgregori (Cox, 1870), almost half of the 10% whorls
of the shell are above the apex of the soft parts (fig.
55a). In Libera fratercula (fig. 55b), a seven-whorled
shell may have only the lower 3V4 whorls occupied by
the animal. As outlined elsewhere (Solem, 1969b), the
upper whorls are filled with calcium carbonate by the
snail and thus provide a source of shell calcium for the
young that hatch in the brood chamber, then eat their
way out through the shell apex. So far as is known,
this is the only species in the Endodontidae to fill in
the apical whorls with calcium, but in most of the
species a part to all of at least the nuclear whorls are
not occupied by the adult animal. Because only a few
species were available with shell and soft parts still
together, I can present no statistical data concerning
the variations in withdrawal from the upper whorls.
Coxia macgregori was chosen for comparison
because it shows the greatest whorl count of any
aulacopod land snail species available to me with soft
parts. A member of the limacacean family
Trochomorphidae, it obviously differs in having a
typically sigmurethrous ureter (KD) and in numerous
genital and radular features, but it is comparable in
terms of elongation patterns. The pallial cavity is
about 1% whorls long, the stomach occupies seven-
eighths whorl after a space for the albumen gland and
intestinal loops, the ovotestis (G) is strung along
almost five-eights whorl, and the digestive gland
extends 23/4 whorls above the ovotestis apex. The upper
5Vs whorls of the shell are "empty space." In Libera
the pallial cavity extends about seven-eighths whorl,
followed by a short gap for the albumen gland and
intestinal loops, with the stomach occupying a full
one-half whorl, the ovotestis a little less than one-half
whorl, and the digestive tissue extending nearly l'/4
more whorls. A total of slightly over 3V4 whorls in the
seven-whorl shell is "adult occupied" in Libera,
compared with the 5% of 10% whorls in Coxia. The
details of organ lengths are different, but the general
pattern of withdrawal from apical whorls is equivalent.
This is one way of partly coping with increased
visceral hump length. Yet another way is through
differential elongation of organs. The counterpart of
visceral hump elongation in many whorled shells is
visceral hump shortening in "semi-slugs," where organs
must be compacted, rather than elongated. In both
situations the change seems to occur in morphological
KX
IZ
HG
KD
FIG. 55. Animal length and shell whorl count in elongated taxa:
a, Coxia; b, Libera f. fratercula. Identified structures are: A - anus;
G - ovotestis; GD - hermaphroditic duct; GG - albumen gland; HG -
hindgut; IZ - stomach; K - kidney; KD - ureter; KX - ureteric pore;
MC - mantle collar; Z - digestive gland.
zones that encompass all the organ systems that pass
through the zone. If the pallial cavity is elongated, for
example, the pallial gonoducts will lengthen, whereas
if the head and neck are elongated (or compacted) it is
the terminal genitalia whose proportions will be
shifted.
The most frequent example of this alteration in
the genitalia of the Endodontidae, and the easiest to
quantify, is the change in relative lengths of the free
oviduct and prostate. For 43 taxa it was possible to
score this feature, with 10 taxa (three Cookeconcha,
two Orangia, Nesophila tiara, Taipidon centadentata,
T. varidentata, Thaumatodon hystricelloides, and T.
euaensis) having the free oviduct distinctly shorter
than the prostate, 14 taxa (two Ruatara, Opanara
altiapica, three Taipidon, two Planudonta, Libera
cookeana, four Aaadonta, and Thaumatodon
spirrhymatum) having them about the same length,
96
SOLEM: ENDODONTOID LAND SNAILS
15-
14-
13-
12-
11-
10-
9-
8-
7-
6-
5-
4-
3-
2-
1-
*** *
T
I
6 7 8
Shell Diameter
I
10
I
11
I
12
I
13
FIG. 56. Penis length and shell diameter in the Endodontidae. Those species with columellar muscle origin of the penial retractor are
indicated by "dots," those with diaphragm origin by "stars."
and 19 taxa (one Minidonta, three Opanara, one
Rhysoconcha, Orangia maituatensis, two Austral-
donta, Taipidon fragila, Nesodiscus fictus, two Endo-
donta, five Libera, Aaadonta fuscozonata, and Price-
concha) having the free oviduct much longer than the
prostate. Species with these three states do not differ
significantly as groups in either shell size or whorl
count. The small Minidonta and Rhysoconcha, for
example, which have about five whorls, have the long
free oviduct, and yet Orangia cookei has a short free
oviduct. If there is a shift within a genus or between
derivative genera from short to equal, or equal to long,
then there is a significant (half whorl or more)
increase in whorl count.
TABLE LVII. - PATTERNS OF AULACOPOD RADULAR DENTITION
Family taxon
Total teeth
Number of -
X rows Lateral teeth Marginal teeth
Endodontidae 3,550 (2,850-1+, 095) 98.it
(6, 8, 37, 22)
Charopidae 3,76? (2,100-9,380) 102.7
(15, 15, 58, 58)
Microcystinae 11,750 (3,850-31,800) 98.3
(111, 127, 129, 1^3)
Euconulinae 12,875 (U, 550-36, 900) 96.0
(17, 19, 18, 20)
Helicarioninae 26,800 (3,900-63,000) 107.1
(13, ll+, 16, 17)
Trochomorphinae lU,150 (1+, 700-25,600) 121+. 5 IQ.I (5-17)
(28, 28, 31, 31)
7.2 (5-23)
7.1 (3-18)
8.0 (2-13)
8.U (1-12)
16.9 (5-38) 103.1 (30-252)
1+3.8 (19-70)
11.2 (7-19)
1^. 5 (6-32)
1+8.3 (21+-175)
5l+. 7 (19-137)
TABLE LVIII. - MAJOR DIFFERENCES BETWEEN ENDODONTIDAE AND CHAROPIDAE
Character
Ovotestis
Prostate-uterus
Epiphallus
Verge or vergic papilla
Terminal female organs
Kidney
Secondary ureter
Radular laterals
State in -
Endodontidae
many follicles in
line along duct ;
angled to shell axis
s epar at e due t s
usually absent ,
penis chamber derived
absent
simple tubes
weakly bilobed
absent
bicuspid
Shell apical sculpture radials usually dominant,
microspirals "squiggly"
Apertural denticles
present; microdenticles
uniformly triangular
Shell sculpture formation
mostly in
calcareous layers
Charopidae
few follicles in
usually one or two clumps ;
curved around axis
fused with a common lumen
usually present,
vas deferens derived
often present
usually internal
complex structures
strongly bilobed
present
almost always tricuspid
spirals usually dominant
in Pacific Island taxa
absent in most ,
when present
microdenticles variable
mostly in
periostracal layers
97
98 SOLEM: ENDODONTOID LAND SNAILS
TABLE LIX. - MINOR DIFFERENCES BETWEEN ENDODONTIDAE AND CHAROPIDAE
Character
State in -
Talon head
Albumen gland
Prostate
Uterus
Penis pilasters
Penial retractor
insertion
Endodontidae
elongately oval
longer, rarely indented
by intestine, alveoli smaller
alveoli larger, shorter,
in rows
less sharply differentiated
two longitudinal
penis apex or side
Spermathecal insertion
Mantle glands onto
pallial roof
Radular central
variable
often
slightly smaller
than 1st lateral
Charopidae
globose
shorter, usually indented
by intestine, alveoli larger
alveoli longer, slenderer,
irregular spacing
sharply differentiated
highly variable,
but not two longitudinal
penis-epiphallus junction,
epiphallus, or penis with
vas deferens piercing muscle
free oviduct
rarely
much smaller
than 1st lateral
This is a simple space problem solution. The
relatively featureless free oviduct and vas deferens
sections of the genitalia tend to lengthen more than do
the prostate and uterus, which are more complex in
structure.
The penis, with its retractor muscle, generally
extends from the atrium to the pallial cavity apex.
Variations in the proportions between penis length and
penial retractor muscle length were not studied. Since
the penis length was recorded, it is possible to plot it
against shell diameter for either the dissected individ-
uals or the mean diameter for that species. The results
are presented in Figure 56; those species in which the
penial retractor muscle origin has shifted to the
columellar muscle are indicated by "dots," while those
with diaphragm origin are indicated by "stars." The
greater penial length obtainable with the shift to the
columellar muscle origin is obvious. Particularly since
the penis can vary in length because of interactions
with sympatric congeners (p. 82), the close correlation
between shell diameter and penis length is quite
remarkable. Their correlation coefficient is 0.82 when
the columellar insertion taxa are excluded, and 0.74
even if they are included. Thus the departure of penis
length from the plotted regression line in Figure 56
could be used as a quick estimate to see whether
species interactions were involved as a selective factor
in the penis length of an endodontid, when compared
with others in its genus. The taxa furthest from the
regression line to the right are the two Nesodiscus.
Why they should have such a relatively short penis is
unknown.
Summary of anatomical variation
The Endodontidae have a basically conservative
body plan that offers a number of contrasts to the
structures seen in the Charopidae. These differences
are summarized in Tables LVIII and LIX as part of
the family level classification discussion. Many fea-
tures of the anatomy in the Endodontidae — penis
length, degree of jaw fusion, stomach length, esopha-
geal length, length of hermaphroditic duct, proportion-
ate lengths of free oviduct and prostate — vary in
direct relationship to whorl count and body size.
Changes in organ position and shapes in the pallial
complex relate to shell barriers and shell shape
features as space accommodations, while partial coiling
of the hermaphroditic duct may serve as an indicator
of whorl count reduction from the condition found in
the immediate ancestors.
Other features, particularly involving the penis
pilaster pattern, seem to be involved in species
recognition among sympatric congeners and have great
utility to the taxonomist in sorting out "sibling
species." Both penis length and possibly the length of
the talon shaft also may be involved in species
recognition interactions. Very limited data suggests
that possibly the size and shape of radular central and
lateral teeth may be involved in niche specialization,
PATTERNS OF MORPHOLOGICAL VARIATION
99
but the work needed to test this hypothesis could not
be undertaken.
There are comparatively few clear progressive
trends in anatomical variation or addition of new
structures, which stands in very marked contrast to
the situation in the Charopidae. There is a change in
pilaster shape from low and rounded to high and
lamellate. Several taxa show a tendency toward adding
glandular tissue between the penis head and penial
retractor muscle, thus giving a potential for "epiphal-
lic" secretions. One group, the Thaumatodon-Aa-
adonta complex, has the penial retractor shifted to the
side of the penis, a much altered entrance of the vas
deferens, and thus an equivalent to a "penial epi-
phallus" has developed. In Taipidon and Planudonta,
the only Marquesan endodontids, there is addition of
a pustulate zone on the penis interior that has no
equivalent in other genera. In two separate areas,
involving the Hawaiian Cookeconcha and the two
Marquesan genera, there is an expansion in radular
tooth numbers.
Other features, such as the origin of the penial
retractor muscle (diaphragm or columellar muscle)
and spermathecal insertion (on penis, atrium, or free
oviduct), vary without direct size correlation and the
changes occurred in several lineages. The shift of the
penial retractor muscle to the columellar muscle does
permit a definite increase in penis length, but there is
no indication of any size "trigger" to this shift.
Probably it occurred as a rare mutation, with the
resultant opportunity for penial enlargement providing
the size-release mechanism.
HABITAT RANGE AND EXTINCTION
With few exceptions, data on the observed niche
for endodontids are monotonous. Found under stones,
in talus slopes, in or under rotting logs, in leaf litter in
heavy forest — all summarize the classic pattern for
litter-and-leaf-mould forest dwellers. Essentially all
localities involve primary forest situations. The
endodontids were ground stratum inhabitants of
"primary forests" on the Pacific Islands.
There are only a handful of exceptions. Pilsbry
and Vanatta (1906, p. 783) reported that species of
Cookeconcha "live on dead stumps and logs, and under
the bark of dead trees, but also among fallen leaves."
They also have been found in heavy moss on large
boulders and at low levels on tree trunks (Solem,
personal observation). Libera b. bursatella was taken
in the axils of Freycinetia at 4,700-5,500 ft. elevation
on Mt. Aorai, Tahiti. The Lau Archipelago Price-
concha tuvuthaensis Solem (1973d, p. 24) was taken on
tree trunks up to 10 ft. above ground level. Libera
fratercula lives in coastal forests on several islands of
the Cook group and has become adapted to living
under coral rock in the narrow shore zone of storm-
tossed boulders (pp. 418-419). Material of Rhysoconcha
was collected by members of the Mangarevan Ex-
pedition from coffee plantations, native forest, and
mixed vegetation areas in the Maitua region on Rapa.
The resulting apparently hybrid populations of Rhyso-
concha from ecotonal stations present a highly
interesting phenomenon (pp. 264-265).
The Cookeconcha and Libera bursatella ex-
ceptions are in zones where the rainfall exceeds 175-
200 in. annually, so that water conservation selective
pressure would be minimal. Why L. fratercula exists
successfully in a shore zone that is subject to at least
short periodic droughts is unknown. The general
pattern of the endodontids being restricted to the
ground level of primary forests is clear. This contrasts
greatly with the Charopidae, where a large number of
species are arboreal or semi-arboreal. This difference
probably can be explained by the difference in
excretion regimes. The Charopidae possess a water-
conserving secondary ureter, while the Endodontidae
do not. They must periodically use part of the pallial
water reservoir to evacuate excreted matter, and thus
are more tightly tied to the high humidity levels of the
primary forest ground stratum. In Australia, New
Zealand, New Caledonia, Viti Levu, Upolu, and Tahiti,
I have found charopids in non-primary forest and even
on the fringes of plantations, but except for the
records of Libera fratercula and Rhysoconcha, no
endodontids have been taken from disturbed primary
forest or secondary vegetation zones. This could relate
to the change in litter composition and/ or humidity
levels when the forest is opened up to sunlight drying,
or a subtle alteration in food source. In Hawaii, on
both Oahu and Kauai, traces of endodontids were
found only in isolated high mountain patches of native
plants, while on the island of Upolu, Price and I took
material of Thaumatodon hystricelloides (Mousson)
only at relatively high elevations in heavy forest that
had not been invaded by introduced ants (see Wilson
and Taylor, 1967 for an account of introduced
Polynesian ants). In the 1860's, T. hystricelloides was
common in lowland forests, but today it is restricted in
its distribution. This correlates with the presence or
absence of introduced ants, particularly the rapacious
Pheidole megacephala.
On both Oahu and Upolu, I have observed the
concordance between the presence of swarming ants
and the absence of many endemic snails and insects.
This was documented in detail by Zimmerman (1948,
pp. 172-177) for Hawaii. The possibility that this exists
in relation to the endodontid fauna of Rapa, for
example, has considerable evidence in its favor. Wilson
and Taylor (1967, p. 6, table 2), record eight species of
introduced ants from Rapa. From September 6, 1963
through December 15, 1963, J. L. Gates Clarke of the
National Museum of Natural History collected insects
and some land snails on Rapa (Clarke, 1971, pp. 1-26).
Through the kindness of Dr. Joseph Rosewater, it was
possible to examine this material. Endemic tornatellin-
ids and zonitids were represented, but there were no
endodontids. Subsequently, Dr. Harald Rehder of the
National Museum of Natural History visited Rapa to
collect marine mollusks. He is also an experienced land
snail collector and, at my request, made a special trip
to the Maitua area and searched, without success, for
endodontids. Clarke (1971, p. 10, fig. 12) illustrated yet
another disturbing factor in the ecology, the presence
of goats on even some of the very steepest slopes. The
ability of goats to seriously alter ground strata
environments is legendary.
The reason for the apparent endodontid absence
wherever ants are common probably relates not to
adult predation, since the apertural barriers of
endodontids would presumably be effective against ant
100
HABITAT RANGE AND EXTINCTION
101
predation, but to egg or juvenile predation. The habit
of egg deposition in the shell umbilicus common to
endodontids would provide no protection against the
ant mouth parts. Hence establishment of a foraging
ant colony in an area could easily prevent successful
reproduction of endodontids through continued loss of
eggs from the umbilical cavities, even though conceiv-
ably the adults might not be bothered.
Between the visits to Rapa of the Mangarevan
Expedition of the Bishop Museum in 1934 and Clarke's
visit in 1963, "noticeable reduction of forest" occurred
(Clarke, 1971, p. 9). The combination of reduction in
forest cover, high-altitude disturbance by goats, and
activities of ants easily could combine to produce great
reduction, if not near total extinction of the endodon-
tid fauna on Rapa. The Mangarevan endodontids had
been wiped out by habitat alteration prior to 1934, and
it may well be that the Rapan radiation has joined the
ranks of the extinct.
The material of Priceconcha (Solem, 1973d, p. 24,
fig. 19, a) was heavily parasitized and this could
indicate yet another factor limiting the current
western distribution of the Endodontidae. No other
endodontid or charopid specimens were seen with any
trace of parasites.
Habitat disturbance, introduced predatory ants,
and possibly parasites acting separately or in
combination would effectively explain the rapid ex-
tinction of the endodontid fauna. Because of structural
limitations in the pallial complex, they basically were
restricted to ground strata in primary forests and thus
were among the first taxa destroyed or displaced by
human disturbance or the addition of ground-litter
predators. Their low diversity in Western Samoa (only
Thaumatodon on Upolu is known) may well stem from
the presence of endemic ants in Samoa (Wilson and
Taylor, 1967), but not on the Cook, Society, Austral,
Marquesan, or Hawaiian Islands, where endodontids
were quite abundant.
PHYLOGENY AND CLASSIFICATION
Before discussing the variation patterns found
within the Endodontidae, proposing a phylogeny, and
deriving a classification scheme from the proposed
phylogeny, it is necessary to place the endodontoid
snails within a broader context. The higher class-
ification and phylogenetic relationships of gastropods
still are controversial. Elsewhere I (Solem, 1974; In
press B) have discussed the possible origin of snails
and reviewed the higher level classification of land
snails. These papers present several changes from the
summary given in Solem (1959a, pp. 32-36), which was
based on the classic accounts by Pilsbry (1900a, b) and
H. B. Baker (1955).
PHYLOGENETIC POSITION OF THE ENDODONTOID
SNAILS
I concur with Fretter and Graham (1962, p. 612)
that the euthyneurous condition in the Opistho-
branchia and Pulmonata are derived independently. A
basic classification into the Subclasses Prosobranchia,
Opisthobranchia, and Pulmonata thus reflects
phylogeny far better than the split into Subclass
Streptoneura ( = Prosobranchia) and Euthyneura
( = Opisthobranchia and Pulmonata) used by Taylor
and Sohl (1962). Elsewhere I have reviewed the
evidence that the Pulmonata are a grade containing
three superorders, the Basommatophor a,
Systellommatophora, and the Stylommatophora
(Solem, In press B). These groups are "pulmonate" in
the same sense that the monotremes, marsupials, and
eutherians are "mammalian." It is thus quite possible
that the "Pulmonata" is polyphyletic, but in the same
way that the "Mammalia" is polyphyletic.
Within the Stylommatophora, authors either list
12 superfamilies (Thiele, 1931, pp. 492-734) or recognize
a series of higher categories, based on the divisions
proposed and amplified by Pilsbry (1900a, b, 1918,
1948) and H. B. Baker (1955, 1963). Modification of the
latter scheme (Solem, In press B) has been based on
work suggested by the present study that led in turn
to re-evaluating the basic trends along land snails.
This work deliberately parallels the type of analysis
done by Romer, Simpson, and others concerning the
vertebrates. This methodology involves attempting to
delineate the basic patterns of ecological advances
made within a large taxonomic unit, attempting to
identify the physiological factors or the structures
(preadaptations) that permitted crossing ecological
thresholds, and then identify the adaptations that
permitted consolidating this gain through successful
adaptive radiations. In the absence of any direct
evidence from fossils, determining convergence in
structures through analysis of ontogenetic changes is a
powerful tool, since the same structure, if developed in
different ways, does not suggest close phyletic relation-
ship but rather equivalent life styles. This can be
applied more successfully to snails than many groups,
since the shell grows by edge accretion, leaving a
frozen record of life stages visible even when the
animal is fully adult.
The basic problem of land life for a snail is water
conservation. The land-dwelling prosobranchs have an
open pallial cavity, are active only under conditions of
very high humidity, and depend for water conservation
on sealing themselves behind the operculum when
retracted. The pulmonates have bonded the mantle
cavity to the body, retaining a pallial cavity that is
open to the exterior through the pneumostome. This
greatly reduces water loss, and, in addition, permits
the pallial cavity to hold a significantly large reserve
supply of extrasomatic water (Blinn, 1964). In marine
mollusks and land prosobranchs the kidney opens near
the posterior of the pallial cavity. In the marine and
fresh-water species, water currents sweep the excreted
matter out of the cavity, but in land prosobranchs this
option is not available. Pallial water or a "squirt" of
excreted water must be used, at least occasionally, to
flush out excreted matter.
In the Basommatophora (Delhaye and Bouillon,
1972a) the land-dwelling Ellobiidae have a simple
kidney with no ureter, while the fresh-water dwellers
have an anterior nephridial pouch that is involved in
osmoregulation. The whole kidney is elongated and
extends well toward the anterior edge of the pallial
cavity. In groups such as the Planorbidae (F. C. Baker,
1945, pis. 44-47) there is a reflexed anterior termina-
tion that has been called a ureter.
In the Stylommatophora there are fundamentally
different structural patterns that have been used, first
by Pilsbry (1900a, b), to delineate several orders. The
basic configurations of the pallial complex in the
ordinal groups as outlined by Pilsbry (1918, 1948) and
H. B. Baker (1955, 1963) were summarized in an
earlier paper of mine (Solem, 1959a, pp. 32-35, fig. 1).
There are only three basic configurations among the
five orders. The kidney in the Orthurethra resembles
102
PHYLOGENY AND CLASSIFICATION
103
that of the Basommatophora in that it extends far
forward toward the pneumostome, tapering gradually,
and ending in an anterior ureteric pore that opens
inside a reflexed ridge that extends partly posteriorly
(Pilsbry, 1900a, pi. XVII, fig. 3). In the Mesurethra,
the kidney is shortened and triangular and remains at
the pallial cavity posterior; there is no strong anterior
extension of the kidney and the ureteric pore is a
simple opening at the anterior kidney tip. This
condition is found in the Cerionidae, Clausiliidae,
Strophocheilidae, and Dorcasiidae, but not the Coril-
lidae (Solem, 1966a, pp. 94-95) which originally were
included in the Mesurethra. The Sigmurethra have a
ureter starting at or near the anterior tip of the
kidney, following its upper margin back to the
posterior of the kidney, then reflexing forward along
the hindgut as either an open groove (most
Holopodopes) or closed tube that is heavily vascular-
ized (most Aulacopoda and Holopoda). The initial
backward extending part is called the "primary ureter"
and the section along the hindgut the "secondary
ureter." Delhaye and Bouillon (1972b) reported that
the orthurethran kidney differs significantly in histo-
logical structure from that of the Sigmurethra, and
they propose that the Sigmurethra were derived from
the Mesurethra by addition of the ureter to the
mesurethran kidney. Rather than the Sigmurethra
being descendants of the "more primitive" Orthu-
rethra, these taxa are parallel experiments probably
derived independently from the "Urpulmonata," what-
ever group that may be.
The above summarizes the basic structural pat-
terns seen in the stylommatophoran pallial complex.
On the basis of both gross morphology and histology,
the orthurethran kidney is very different from that of
the mesurethran and sigmurethran lineages. The
derivation of sigmurethran type from the mesurethran
situation has an appealing simplicity, but requires
further investigation because of complicating vari-
ations in several groups. The two ordinal groups with
variations from these basic patterns are the Tracheo-
pulmonata (Family Athoracophoridae) and Heteru-
rethra (Family Succineidae). The former are slugs with
the visceral hump organs compressed completely into
the foot cavity. Their multi-looped ureter is a
secondary modification to the visceral hump reduction.
The heterurethrous pallial configuration was suggested
by H. B. Baker (1955) as the probable ancestral
condition to the Sigmurethra. Elsewhere I (Solem,
1969b; In press B) have reviewed the relationships of
the Succineidae and suggested that they are modified
Sigmurethra rather than being primitive. Bouillon and
Delhaye (1970) reported that the basic structure of the
kidney and ureter in the Succineidae and Sigmurethra
were the same, but subsequently (Delhaye and
Bouillon, 1972b, p. 141) concluded that because the
opening from the kidney into the ureter differs in the
Sigmurethra and Heterurethra, they are not related.
Generally, they live under quite different water
regimes, the Heterurethra in semi-aquatic and the
Sigmurethra in terrestrial, often water shortage condi-
tions. The addition of a sphincter to the kidney pore in
the Sigmurethra, or its secondary loss in the Hete-
rurthra, if my interpretation of their relationships is
correct, is not a major difference.
I consider it highly significant, in terms of judging
relative phyletic position, that all land-slug taxa have
sigmurethrous ureters. There is great water
conservation potential in the closed, complete ureter
that opens to the exterior at the pneumostome. This
permits keeping the pallial water supply for replacing
water evaporated from the extended head and foot.
The ureter can function to resorb water from the
excretory products, and no pallial water need be used
to flush out the excretory products. The evolution of a
"pseudosigmurethrous" pallial structure in some enids
(Solem, 1964) is another point suggesting the funda-
mental importance of the pallial structures to progres-
sive land-snail evolution.
With this background information, the pallial
complex in the Endodontidae can be compared with
the basic patterns. It is closest to the sigmurethrous
condition, but in having only a primary ureter, with no
trace of a secondary ureteric groove or tube, it
represents a significantly different structure. A possi-
bly parallel situation is seen in the Australian
Caryodidae, where the primary ureter opens
posteriorly, without there being any rectal kidney lobe,
much less the slight reflexion of the ureter seen in the
Endodontidae. The similarity is undoubtedly
convergent, since the endodontid and caryodid ureters
are very different in internal structure (Solem,
unpublished). Whether the ureter in the Endodontidae
is a forerunner of that seen in the Charopidae and
typical Sigmurethra, or an independent experiment is
uncertain. Certainly this represents a major difference
in structure. The orthurethrous kidney is too different
to be viewed as a potential ancestor to the endodontid
condition. In terms of pallial complex configuration,
the Endodontidae are less advanced than the rest of
the Sigmurethra, but more advanced than the Mesu-
rethran taxa. There is no evidence at all that the
Mesurethra are ancestral to the endodontoid group.
In respect to other organ systems, the trends of
variation are either less clearly delineated, or else
simply have not been analyzed in sufficient detail to
permit firm phyletic statements. To summarize the
limited data presented elsewhere (Solem, In press B),
in general, it would be correct to say that taxa with no
spermatophore formation (=no differentiated epi-
phallus), no accessory dart sacs or mucus glands, no
vergic structure, and separated pallial gonoducts
(prostate and uterus completely separate tubes) are
more "primitive" (= generalized) than those with a
hard spermatophore, dart sacs and/or mucus glands, a
verge, and united pallial gonoducts. These criteria
are based on the assumptions that: 1) hermaphrodit-
104
SOLEM: ENDODONTOID LAND SNAILS
ism in snails was achieved by combining separate male
and female systems. Union of ovary and testis into an
ovotestis was followed by subsequent union of progres-
sively lower portions of the pallial gonoducts (Solem,
1972b, pp. 108-112); 2) transfer of sperm by snails in a
"protective package" is (subject to secondary
modification) more advanced than transfer of sperm
loose in fluid (for mollusks, not mammals). The
"advanced" conditions have been arrived at indepen-
dently in each of several lineages, judged by analysis of
structures in groups with different types of such
accessory structures. The helicarionid, helicid, and
helminthoglyptid dart sacs, for example, are very
different in structure, although performing identical
functions. Union of the prostate and uterus into a
"spermoviduct" can be traced as separate devel-
opments in at least helicid, helicarionid, endodontoid,
partulid, pupillid, and ellobiid stocks (Solem, 1972b).
H. B. Baker (1955, 1956, 1962a) recognized three
major groups among the Sigmurethra. The Au-
lacopoda and Holopoda, established by Pilsbry (1896),
differ in foot structure, pedal groove presence or
absence, basic radular features, and shell character-
istics. The Holopodopes contains mainly elongated
herbivorous and specialized carnivorous taxa that
show numerous differences from the other groups. The
Holopoda are universally accepted as being more
advanced and, in most characters, are derivable from
the Mesurethra. Relationships of the Holopodopes to
the other groups are uncertain.
The endodontoid snails have the basic foot and
radular structures of the Aulacopoda. While the
Charopidae have a sigmurethrous ureter, differentiated
epiphallus, usually a verge, and fused pallial
gonoducts, the Endodontidae lack a secondary ureter,
only rarely have any indication of an epiphallus, lack a
verge, and have separated pallial gonoducts. Thus the
Endodontidae have aulacopod features, but in the few
pallial and genital structures where it is possible to
make any positive statements concerning primitive
versus derived characters, in every case the Endodon-
tidae show the primitive condition. Because of basic
differences in structure, it is not possible to derive the
Sigmurethra from the Orthurethra. The large and
specialized Mesurethra show many genital features
that are more advanced than the structures seen in
the Endodontidae. We are thus left with an inability
to focus on any group of living land snails as
possessing a greater number of generalized structures
than the Endodontidae. Questions concerning poten-
tial derivation of the other endodontoid families from
the Endodontidae are deferred until the second
monograph. Family groupings for the more advanced
endodontoids also will be considered elsewhere, except
for the many comparisons with the Pacific Island
Charopidae.
The basic division within the Aulacopoda was
recognized by Pilsbry (1896, p. 110), who characterized
the superfamilies later named Limacacea (H. B. Baker,
1941, p. 206) and Arionacea (H. B. Baker, 1955, p. 109).
The cited "key character" was the structure of the
radular marginal teeth, but the smooth and shiny,
often colorful "limacoid" shell, frequent development
of highly elaborate accessory genital structures, and
strong development of mantle collar lobes and exten-
sions in the Limacacea, stand in great contrast to the
dull, heavily sculptured, frequently flammulated shell
and comparatively rare development of accessory
genital structures or mantle extensions in the
"endodontoid" Arionacea. Preliminary work (Solem,
unpublished) suggests that some of the Austrozelandic
arionaceans ( = advanced Charopidae) may be partly
transitional in some characters to the shell-bearing
limacaceans. The general "Gondwanaland" dominance
of the arionaceans and "Laurasian" dominance of the
limacaceans probably have influenced the general
acceptance of the Limacacea as the derived taxon.
This view very probably is correct, but presentation of
the evidence must be postponed.
Although the basic difference between the Ario-
nacea and Limacacea is usually cited as the shape of
the marginal teeth — narrow, lengthened basal plates
with unicuspid, multicuspid, or bicuspid teeth in the
Limacacea and short, wide, often squarish basal plates
with unicuspid or several cusped teeth in the Ario-
nacea — there also are differences in the sheer number
of teeth. The data are spotty, particularly since few
row counts were made during this study and my
observations on the number of marginal teeth in the
Endodontidae and Charopidae are quite incomplete.
Nonetheless, the basic trend is clear.
Data have been compiled from this report for the
Endodontidae. Many tooth counts, but few row
counts, are available for the New Zealand Charopidae
(listed as Phenocohelicidae, Endodontidae, and Oto-
concha) from Suter (1913, pp. 620-732). Massive
information on the Pacific Island limacacean radulae
was presented by H. B. Baker (1938b, 1940, 1941). A
rough estimate of the total teeth on each radula was
calculated by multiplying the individual row count by
the number of rows on the radula. Counts of lateral
teeth and marginal teeth in a half row for each species
were averaged for major taxonomic units. These data
are summarized in Table LVII. The numbers under
the taxon name refer to the number of observations
included in each column to the right. The clas-
sification of the limacacean groups is slightly altered
from H. B. Baker, in that the Trochomorphidae is
listed as a full family; and the Helicarioninae includes
the Sesarinae of H. B. Baker (1941, pp. 238-263) as was
suggested earlier (Solem, 1966a, pp. 22-24).
The low total tooth count on the radulae in the
Endodontidae and Charopidae stands in great contrast
to the situation in the limacacean groups. The figure
for the Endodontidae omits the two Taipidon with
grossly enlarged tooth counts. They are quite atypical
for the family. Their inclusion in such a small sample
PHYLOGENY AND CLASSIFICATION
105
would distort the results. The slightly higher marginal
tooth count for the New Zealand Charopidae reflects
the inclusion of the several "flammulinids" with
altered marginal teeth. These are altered not only in
tooth number, but also in form and cusp structure to
the point that Suter (1894a, p. 62) had stated that
"the radula is more or less pseudo-zonitoid" in these
genera.
The Microcystinae and Euconulinae, which are
the most generalized and smallest sized members of
their respective families, have added only one lateral
tooth, but tripled to quadrupled the number of
marginal teeth. This change in both number and tooth
form of the marginals suggests a major shift in feeding.
By use of critical point drying techniques followed by
SEM observation with the radular ribbon in a normal
position (see Runham, 1969, fig. 1, for an example of
this technique) much information could be gathered
on the differences in functioning. This could be the key
to understanding the adaptive shift from the arionoids
to the limacoids.
While the Euconulinae and Microcystinae are
comparable in adult size to the Endodontidae and
Charopidae, the Pacific Island Helicarioninae (Or-
piella, Dendrotrochus, Ryssota, Epiglypta, Helicarion)
are 10-55 mm. in shell diameter, and thus much larger
in size. Similarly, the Trochomorphidae are mostly 8-
20 mm. in shell diameter, again substantially exceeding
the endodontoids in size. Hence the increased number
of tooth rows in both taxa, and greatly increased tooth
numbers in the Helicarioninae can be partly the result
of simple size increase. This only accentuates the basic
pattern in which the limacaceans are seen to differ
mainly through the multiplication and change in form
of the marginal teeth on the radula. A comparative
study of the more generalized limacaceans and the
Austrozelandic charopids with "pseudo-zonitoid" teeth
might yield considerable data on the inter-relation-
ships of these superfamilies.
In summary of the above discussion, the en-
dodontoid snails are a group that are "comfortably
sigmurethran" (Charopidae) to "protosigmurethran"
(Endodontidae). They comprise the least specialized
complex of the Aulacopoda. This group parallels the
Holopoda, but is not as probable an ancestor to the
Holopoda as would be the Mesurethra. While several
family groups may be derived from the endodontoid
complex (including the Limacacea), no extant group of
land snails can be pointed out as possibly representing
the stem group for the endodontoid complex. The
statement that the "Endodontidae probably are the
most primitive living sigmurethrans" (Solem, 1959a, p.
77), which was based more on intuition than evidence,
has not been altered by more than a decade of patient
poking into endodontoid guts. What has been altered
is the concept of family units and definitions expressed
in the same paper. A review of family units precedes
discussion of phylogeny within the Endodontidae.
FAMILY CLASSIFICATION OF THE ENDODONTOIDS
The following family level names are available for
endodontoid snails. They are listed in order of
nomenclatural priority.
Punctinae Morse (1864, p. 27)
Patulinae Tryon (1866, p. 243)
Charopidae Hutton (1884b, p. 199)
Phenacohelicidae Suter (1892a, p. 270)
Otoconchinae Cockerell (1893, pp. 188, 205)
Endodontidae Pilsbry, 1895 (Pilsbry, 1893-1895, p. xxviii)
Flammulinidae Crosse (1894, p. 210)
Thysanotinae Godwin-Austen, 1907 (Godwin-Austen, 1889-1914,
p. 189)
Laominae Suter (1913, p. 732)
Goniodiscinae Wagner (1927, p. 305)
Helicodiscinae Pilsbry in H. B. Baker (1927, pp. 226, 230)
Rotadiscinae H. B. Baker (1927, pp. 226, 228)
Stenopylinae Thiele (1931, p. 569)
Amphidoxinae Thiele (1931, p. 575)
Discinae Thiele (1931, p. 578)
Dipnelicidae Iredale (1937b, pp. 22-23)
Paralaomidae Iredale (1941a, p. 263)
Hedleyoconchidae Iredale (1942, pp. 34-35)
Pseudocharopidae Iredale (1944, p. 312)
The Iredale taxa are virtually nomina nuda, and
consideration of the extralimital units Thysanotinae,
Goniodiscinae, Discinae, Helicodiscinae, Rotadiscinae,
Amphidoxinae, and Stenopylinae is deferred. Of the
remaining taxa, the name Patulinae is ignored for the
following reasons. The describer (Tryon, 1866, p. 242)
noted that the Patulinae was "not proposed with any
intention but to facilitate the determination of
species." Although used as a family name by
Moellendorff (1890, p. 221; 1900, p. 109), it has been
ignored by other authors of that period and by
subsequent students, until listed with disapproval by
H. B. Baker (1956, pp. 134, 138). It is now equivalent in
modern context to the Goniodiscinae and Discinae,
since the genus Patula, after a very long and
checkered career, has settled as a subjective synonym
of Discus. May both Patula and Patulinae rest in
peace.
Morse (1864, p. 27) established the Punctinae on
the basis of having a jaw composed of 16 distinct
plates, and minute radular teeth that he thought
resembled those of Carychium, an ellobiid, under
optical study. There are shell, radular, and genital
features which combine to separate the Punctidae as a
family unit (Solem, unpublished). The Laominae of
Suter (1913) is not separable from the Punctidae, as
has been recognized by Pilsbry (1893-1895), Thiele
(1931), and Climo (1969a).
The first use of the name Charopidae (Hutton,
1884b, p. 199) was based on the heliciform shell and
development of a caudal mucus gland. The latter
feature, which not only is very characteristic of
arboreal snails in general, but is highly variable in
degree of development at a very low taxonomic level,
was the subject of more than a decade of controversy
concerning endodontoid classification. In a series of
papers Pilsbry (1892a, pp. 54-55; 1892b, pp. 68-69;
106
SOLEM: ENDODONTOID LAND SNAILS
1893a, pp. 401-402; 1893b), Hedley (1893a, p. 163), and
Ihering (1893, p. 121) downgraded the importance of
this character, although Crosse (1894, pp. 210, 219) and
Moellendorff (1895, pp. 157-158; 1899; 1900, p. 109)
gave primary importance to the caudal mucus pore.
Suter (1892a, p. 270) had proposed the family unit
Phenacohelicidae, citing the "caudal gland" as a
significant feature, but subsequently (Suter, 1894a, p.
62) agreed with Pilsbry and stated "I do not attach
very great importance to the presence or absence of
the caudal gland, as we really do not know its true
significance; but in the mollusks classed under
Flammulina the jaw is always stegognath, the radula
is more or less pseudo-zonitoid, and, besides, a mucous
tail-gland is always present; whilst in Endodonta and
Charopa the jaw is only striated, the radula is much
more helicoid, and there is no caudal gland." Suter was
using Endodonta in a very broad context, and not in
the restricted sense of this study.
Early attempts at classifying the Australian and
the New Zealand endodontoids were made sequentially
in terms of writing, but not in publishing, by Pilsbry
(1892a, pp. 54-55), Hedley (1893a, b), Pilsbry (1892b,
pp. 68-69), Hedley and Suter (1893, pp. 633-660), and
Pilsbry (1893a, pp. 401-402). Pilsbry summarized his
views (Pilsbry, 1893-1895, pp. 6-54) in an annotated
check list, which included his (Pilsbry, 1893a, pp. 401-
404) placing Laoma and Punctum into a "Group
Polyplacognatha" and the remaining into "Group
Haplogona" of the Family Endodontidae. The latter
name must date from February 2, 1895, the publi-
cation date for the introductory pages in that volume.
In his monumental survey of New Zealand
mollusks, Suter (1913) defined the Phenacohelicidae
(p. 621) as with a mucus pore and the Endodontidae
(p. 684) as lacking a pore. He divided the latter family
into two subfamilies, the Endodontinae with tricuspid
lateral teeth and a thin striated jaw, while the
Laominae have bicuspid lateral teeth and a jaw of
separate plates. Suter (1913, pp. 619-621) also included
a peculiar slug-like animal, Otoconcha dimidiata
(Pfeiffer, 1853), as a limacid slug, although Cockerell
(1893, pp. 188, 205) had placed it in a subfamily,
Otoconchinae, without giving any description. Sub-
sequently, H. B. Baker (1938a) stated "I am inclined to
regard it as constituting an aberrant subfamily of the
Endodontidae, but, with almost equal reason, it might
be considered as another primitive member of the
Arionidae or be erected into a separate family, the
Otoconchidae, until intermediate forms are found."
Climo (1969a, 1971a) has used Otoconchinae as a
subfamily unit and provided much important ana-
tomical data on its relatives.
Iredale (1913, p. 375; 1915a, p. 479) continued
attacking the mucus pore (along with all other
anatomical features). Gabriel (1930, pp. 72, 78, 84), in a
major paper, proposed the family units Endodontidae,
Flammulinidae, and Laomidae for Austalian taxa.
Iredale (1937a) adopted this system, without acknowl-
edgment, only substituting the name Charopidae for
Endodontidae and (Iredale, 1937b, p. 26) adopting
Stenopylinae (Thiele, 1931) as a full family unit.
Subsequent efforts by Iredale added four undescribed
family names, but made no meaningful changes in
classification of the Pacific taxa.
Climo (1969a, 1970, 1971a, b) has proposed using a
single family, Punctidae, with four subfamilies, Charo-
pinae, Phenacohelicinae, Punctinae, and Otoconchinae.
The two latter are based on the now traditional jaw
and radular features (Punctinae) and inevitable
consequences of visceral hump reduction (Otocon-
chinae). To distinguish between the Charopinae and
Phenacohelicinae, Climo relied on the presence (Charo-
pinae) or absence (Phenacohelicinae) of an epiphallus.
In many taxa with reduced visceral humps, the vas
deferens-derived epiphallus will be compacted forward
into the penis sheath (Solem, unpublished). Other
dissections suggest that the epiphallus in different
groups of Australian and New Zealand taxa may be
independently derived. In laying to final rest the
mucus gland arguments, Climo has performed a
notable service, but I do not agree with his criteria for
family classification.
Only one extralimital paper requires consideration.
H. B. Baker (1927, pp. 226-235) reviewed the anatomy
and classification of some North and Central Ameri-
can endodontoids. His division into the subfamilies
Punctinae, Rotadiscinae, and Helicodiscinae was based
on changes in pallial cavity configuration and length
of the secondary ureter. The pattern of pallial cavity
change from Helicodiscus (H. B. Baker, 1927, pi. 18,
fig. 42) and Radioconus (pi. 17, fig. 30), to Chan-
omphalus (pi. 20, fig. 52), to Radiodiscus (pi. 17, fig.
24), to Punctum (pi. 16, fig. 12), to Rotadiscus (pi. 16,
fig. 17) would present a virtually continuous transi-
tional series from the pattern found in the Endodon-
tidae to that seen in the Charopidae of the Pacific
Islands. In addition, Rotadiscus (pi. 16, figs, 13, 19)
shows apparently only partial fusion of the prostate
and uterus, while the other genera have fused pallial
gonoducts. It is premature to try to propose a world-
wide classification for this group, since most of the
African, South American, Australian, New Caledonian,
and Lord Howe Island taxa have not been dissected.
The genitalia of the species studied by H. B. Baker
(1927) do have typically "charopid" features, so that
the pallial configurations sequence does not negate the
validity of family level separation.
I propose here a three-family classification of the
Pacific Basin taxa, into Punctidae, Endodontidae, and
Charopidae. The Punctidae have the bicuspid later-
omarginal teeth with accessory cusps mentioned above
(p. 93) and several differentiating anatomical features
that will be discussed elsewhere. The Endodontidae
and Charopidae, as represented on the Pacific Islands,
differ in a number of major (table LVIII) and minor
PHYLOGENY AND CLASSIFICATION
107
(table LIX) anatomical features. There are no known
extralimital representatives of the Endodontidae, but
the Charopidae have their primary abundance else-
where. I include in the Charopidae such taxa as the
Phenacohelicinae and Otoconchinae in the sense of
Climo (1969a, 1971a), Flammulinidae in the sense of
Gabriel (1930) and Iredale (1937a and following),
Hedleyoconchidae, and Pseudocharopidae. The ques-
tion of subfamily divisions within the Charopidae is
deferred until more data are available on Australian
and New Caledonian taxa. The relationships of
northern hemisphere discids and Neotropical taxa are
not discussed at this time.
Suter (1913) based family units on the mucus
gland; H. B. Baker (1927) based subfamilies on the
pallial complex, Thiele (1931) divided the Endodon-
tidae into eight subfamilies on shell and radular
features, Zilch (1959-1960, pp. 203-230) essentially
copied Thiele's classification, except for ranking
Otoconchidae as a distinct family, and Climo (1969a)
used the presence or absence of an epiphallus for
subfamily units. In proposing an increase in rank for
units in the classification, as well as altering both the
number and composition of these units, I must answer
the question as to equivalence with other family units
in the Aulacopoda. The characters of major phyletic
significance used to separate the Endodontidae from
the Charopidae are the absence of the secondary
ureter, the complete separation of the prostate and
uterus, the very simple structure of the terminal
genitalia, and the difference in the ovotestis structure.
The other features mentioned in Tables LVIII and
LIX are useful, but carry less phyletic weight. The
shell structure differences, particularly in the mode of
sculpture formation, may have equally significant
weight, but need further investigation.
The nearest equivalent situation would be the
division of the Pacific Island limacaceans into Helica-
rionidae and Zonitidae by H. B. Baker (1941, p. 205).
His definitions involve divergent patterns of special-
ization, such as development of dart apparatus on the
female (Helicarionidae) or male (Zonitidae) sides of the
terminal genitalia, without listing any equivalent
major structural gaps between family units. One of the
important changes used here is present within the
Helicarionidae. The Microcystinae, the more primitive
group that is dominant on the Pacific Islands, has the
prostate separated from the uterus, while in the other
subfamilies they are united into a "sperm oviduct." But
no equivalent of the other major changes exists in the
Limacacea. All the limacaceans have a typical sigmu-
rethrous pallial complex. There is great specialization
of the genitalia including epiphallus formation and
(except in the Microcystinae) spermatophore forma-
tion with frequent development of accessory genital
structure.
On the basis of degree of difference, the phyletic
gap between the Endodontidae and Charopidae is
wider than the gaps between family units of the
Limacacea.
Much descriptive and some anatomical informa-
tion on extralimital Charopidae can be located in
faunistic studies. The reports on the molluscan faunas
of the Kermadecs (Iredale, 1913, 1915b), Papua
(Iredale, 1941c; Solem, 1970a), Lord Howe Island
(Iredale, 1944), Norfolk Island (Iredale, 1945), New
Caledonia (Solem, 1961), New Zealand (Suter, 1913;
Powell, 1957), and the Australian check list (Iredale,
1937a, b, c) provide summaries of the literatures. The
incredible nomenclatural nightmare of Iredale
(1933) unfortunately cannot be ignored completely,
while his subsequent papers on the faunas of New
South Wales (Iredale, 1941a, b), and Western Austra-
lia (Iredale, 1939) also must be used. The few
Philippine Islands (Solem, 1957) and Indonesian
(Solem, 1958, 1959b) endodontoids also have been
summarized. Connolly (1939) reviewed the South
African taxa, and a brief survey of the St. Helena taxa
is included in Solem (In press A). Data on Neotropical
taxa are very widely scattered.
PHYLOGENY WITHIN THE ENDODONTIDAE
Perhaps the key problem in phylogenetic analysis
today is the question of how to weight characters in
determining phylogeny. Opinions vary from the classi-
cal pheneticists who stated that every character is of
equal weight, to the classical typologists who picked
out single characters on which to base decisions. In
between are the vast majority of systematists. The
present study is more pragmatic than philosophical,
although based on the tiered approach to character
analysis developed in Solem (In press B). I assume
that the major changes involved in progressive evolu-
tion require shifts in ecological roles accompanied by
morphological alterations. Adaptative radiations with-
in such a new zone will involve change at a different
level, while the interactions between sympatric species
will produce yet a third level of evolutionary change.
While the basis of change is genetic, as a practical
matter most systematic work must be with
morphology, expressed as either a direct or pleiotropic
effect of a genetic shift. Biochemical criteria, physi-
ological factors, behavior patterns, and molecular data
would follow similar patterns.
In relation to this study, I consider that the
changes from Endodontidae to Charopidae (strictly
terrestrial to semi-arboreal, wider tolerance of disturb-
ed conditions, changed pallial structures, advanced
genital structures) are representative of progressive
evolution. No such changes were detected within the
Endodontidae, but there are some minor adaptative
shifts and numerous instances of sympatric species
interactions (see pp. 80-81, tables LII - LIV). Because I
have not been able to pinpoint an ancestor group for
the Endodontidae, reference to a more primitive
outgroup for determination of generalized character
108
SOLEM: ENDODONTOID LAND SNAILS
states has not been possible. Instead I have used a
short set of pragmatic guidelines. These are based in
part on the distributional fact that the Pacific Island
endodontoids occur on tiny specks of land that are
widely separated from each other. This has the
practical effect of making a systematist investigate
with great care situations where a species, found on
one of the Palau group, for example, has characters
that appear very similar to or identical with characters
found otherwise only in a Marquesan species. Conti-
nental areas have, in many parts of the world, been
subject to multiple migrations, invasions, extinctions,
and recolonizations because of Pleistocene phenomena.
It is intellectually far more satisfying (and comfort-
able) to accept disjunct similar species on continental
areas as representing distributional relicts of common
ancestry than to assume that the Palau and Marque-
san species had common ancestry.
The basic criteria used in judging change in
character states in regard to individual structures or
complex patterns of growth are:
1) If formed in exactly the same way they are
presumed to have common ancestry;
2) If formed in different ways, although performing
the same function or showing the same end growth
pattern, they are independently derived;
3) Greater complexity may be suggestive of a derived
condition, but if the less complex conditions are non-
coherent with each other, while the more complex
condition has detailed structural consistency, then
secondary simplification is postulated.
In regard to distributional factors, I have assumed
that:
4) Widely distributed character complexes that have
structural consistency probably are ancestral to
sporadically distributed different states of these
complexes that lack structural consistency.
5) Character states of limited geographic occurrence
should be analyzed in terms of development from or
into states of wide geographic distribution.
6) Character states must be interpreted also in
reference to conditions existing among sympatric or
probably sympatric taxa.
7) Character states occurring in only one geographic
area may be either generalized or derived in
comparison with widely distributed states, with
interpretation resting on correlated changes with
other characters that can be interpreted more
objectively.
Examples of the ways in which these criteria have
been applied during this study are:
1) and 2) The apertural barriers in the Endodon-
tidae have the same type of microdenticulations on
their upper surface and therefore the barriers are
assumed to be of common origin, while the barriers
in the Charopidae show different types of structure
and superior microdenticulations, strongly suggest-
ing multiple origins (Solem, 1973b, p. 305). The
brood chamber growth pattern in the Endodontidae
occurs in several different geographic areas. In each
situation the method of secondarily narrowing the
umbilicus is different, suggesting multiple origin of
the growth pattern (pp. 27-30).
3) Reduction of the apertural barriers results in a
very simple ridgelike structure, particularly when
compared with the detailed structures found on the
larger barriers. As shown above (pp. 57,62), the
patterns of reduced barriers are much more varied
than are the patterns of fully developed barriers.
Reduced shell sculpture (pp. 47-50) correlates with
increased shell size and the patterns of reductions
have greater variability than do the basic complex
sculpture.
4) The pattern of the penis with two low pilasters,
the vas deferens entering below the apex, and penial
retractor muscle inserting on the penis apex is
widely distributed, while the additions of epiphallic
tissue to the penis apex and changes in the pilaster
patterns occur sporadically.
5) and 7) The presence of a glandular zone inside the
penes of Marquesan Endodontidae has no counter-
part elsewhere in the family, and, if eliminated, the
penis structure would still be specialized in terms of
the family pattern. Hence this is interpreted as an
additive, specialized structure.
6) The variations in penis size and pilaster patterns
(tables LII, LIII, LIV) are largest when sympatry of
congeners is involved. Hence aberrant structural
patterns in the penis complex are viewed first as
suggesting "species recognition" interactions be-
tween populations. Comparisons must be made with
sympatric or at least same-island taxa before
predicting whether the variation represents a general
adaptational trend or essentially local character
displacement to aid species recognition.
All of the above guidelines are based on the
attempt to understand the ontogenetic development of
structures and to place them within the framework of
species-level interactions. This approach is more
applicable to mollusks than to arthropods or verte-
brates, since the ontogenetic pattern of shell growth is
available in each adult specimen, while obviously
lacking in the adult arthropod or vertebrate. Both the
key to and difficulty of this approach involve the
necessity to interpret not just the final structure, but
to analyze its components and ontogeny as an aid
toward deciding its significance in phylogenetic
analysis.
PHYLOGENY AND CLASSIFICATION
109
TABLE LX. - SHELL PARAMETERS OF THE ENDODONTIDAE
Minimum 1st Quartile Median 3rd Quartile Maximum
Height 0.92 1.58 1.98 2.57 7-26
Diameter 1.68 3.01 3.77 It. 8 5 12.26
H/D ratio 0.3^ 0.1+66 0.531 0.589 0.789
Whorls 3-5/8 5-1/8 5-1/2+ 6-3/8- 8+
D/U ratio1 1.68 3. 11* 3. 9^ 5.6l closed
Ribs2 19 63.6 80.0 IQh.k 250
Ribs /mm. 1.1*1 5-0 7.6 11.1 1+0.1+
Excluding brood chamber taxa
Excluding those without countable ribbing on body whorl
Portrait of a generalized endodontid
Although the most basic trends in the Endodon-
tidae are toward increased size accompanied by
structural alterations, there is evidence that at least
one genus, Rhysoconcha, is secondarily dwarfed (pp.
255-256). It should not be assumed automatically that
the smallest species in size represent the most
generalized taxa. A reduction in adult whorl count also
can effectively produce smaller adult size without
requiring major structural alterations.
Table LX summarizes the distribution of several
shell parameters in the Endodontidae. Allowing for the
tendency toward larger size that often is the pattern in
most taxa, and utilizing data from the discussion given
above on variation in structures, the "generalized
endodontid" structure can be described rather simply.
The shell would be about 3.0-3.5 mm. in diameter, with
51A - 5!/2 whorls, the height being slightly less than
half the shell diameter, and the widely open umbilicus
would be contained about 3.5 times in the diameter.
There would be a prominent sculpture, numbering
perhaps 65-90 ribs on the body whorl, spaced six to
eight per millimeter of shell periphery, and with four
to eight microradials between each pair of major ribs.
The apex and spire would be slightly to moderately
elevated, reaching up to half the body whorl width in
terms of actual protrusion. The body whorl itself
would be rounded or laterally flattened. Inside the
aperture there would be 2 to 3 parietal barriers
extending three-sixteenths to one-quarter whorl
posteriorly, 1 columellar barrier, and 4 palatal barriers
at or near the lip edge that extended one-eighth to
three-sixteenths whorl posteriorly. All the barriers
would be slightly to moderately widened above on the
posterior half to two-thirds, and capped on the
expanded portions with triangular microdenticulations
that point toward the outside of the aperture. The
anterior portion of each barrier would gradually
descend to a sharper truncation in many palatals and
an anterior threadlike portion in the lower parietals.
The net effect of these barriers would be to grossly
narrow the apertural opening, except for a slightly
widened zone in the upper palatal area to permit
effective withdrawal of the head and foot.
In the anatomy, only the few variable features
need to be outlined, since the structural plan is
relatively uniform. The pallial cavity would extend
about three-quarters whorl, with the kidney weakly
bilobed, and probably there would be no mantle gland
extension onto the pallial roof. The genitalia would
have the penial retractor muscle inserting directly on
the head of the penis and originating from the
diaphragm. Inside the penis would be two low and
rounded, longitudinal pilasters, with the vas deferens
opening just below their point of apical union. The
spermathecal insertion is uncertain, and other features
of the genital system seem to vary more in size
correlated features than anything else. The radula
would have about 100 rows of teeth, with a tricuspid
central, five or six bicuspid laterals, and perhaps 10-12
marginals with split cusps. The jaw would be
composed of separate, elongated plates held together
by a thin membrane.
Converting the above description into an ancestor
of the present endodontids probably would involve
only a reduction in shell diameter and whorl count,
with correlated changes in ribbing, D/U ratio, and
pallial length.
Identifiable major trends
Smaller shell size can be reached by the Rhyso-
concha strategy of secondary size reduction without
major reduction in whorl count, or by the pattern that
may exist in the smallest Minidonta, Cookeconcha,
and Mautodontha where greatly reduced whorl counts
are common. By far the most prevalent trend is for
increase in shell size, most often by simple continued
addition of more whorls to the shell. Associated with
this increased size are a tendency for loss of shell
sculpture, fusion of the jaw plates, often a more
elevated spire as the decoiling growth continues,
sometimes lengthening and size reduction of the
110
SOLEM: ENDODONTOID LAND SNAILS
I \ Orangia [
Rhysoconcha [/ *r
^*"^ *r I Kondocon
FIG. 57. Phyletic diagram of the Endodontidae showing hypothesized origins of extant taxa.
apertural barriers, and various minor lengthening
trends as outlined in discussions of the characters
above.
Such simple continued incremental growth in
whorl numbers also will tend toward a very widely
open umbilicus and proportionately higher shell that
may reduce the ability of the animal to crawl into
narrow crevices. The widely open umbilicus partic-
ularly may have led to a functional problem with egg
retention. In some Nesodiscus (p. 345) eggs deposited
in the widely open umbilicus are covered by a solid
sheet of mucus to form an encapsulated situation, but
in at least five groups (p. 28) there has been secondary
narrowing of the umbilicus to form a "brood chamber"
in which the eggs are deposited. Inevitably, widening of
the umbilicus had to precede the secondary narrowing
(fig. 189), and it is the differences in the way that the
narrowing is achieved that indicate separate origin of
this growth pattern. These then are two basic trends
in shell variation — size increase through whorl
accretion leading to first a very widely open shell
umbilicus and a tendency toward secondary narrowing
of the umbilical cavity to form a brood chamber.
Anatomical variations are, in general, correlated
with minor features of shell variation. Only a few seem
to be independent of the trends in shell structure.
Ignoring the "species recognition" changes in genital
structure, the one really striking alteration is in the
pattern of the penis-vas deferens-epiphallus relation-
ship. This is geographically limited. Many Rapan and
most Marquesan taxa show an added zone of glandular
tissue to the penis apex (fig. 46), while the
Palau Island Aaadonta, Fijian Priceconcha, Zyzzyx-
donta, and Thaumatodon have a quite different
entrance of the vas deferens and altered attachment of
the penial retractor, that, in effect, forms a penial
epiphallic section. Other local changes in anatomical
structure that can be called trends are the addition of
a pustulate zone within the penis of Marquesan taxa,
and the tendency for increase in radular tooth
numbers for some Hawaiian and Marquesan taxa.
While many features of the shell sculpture and
apertural barriers were shown above to be partly size
correlated, others vary more within a phyletic unit on
a geographic basis. The obvious change in barrier
microdenticulation from a continuous surface in most
genera to the "beaded" structures seen in the
Aaadonta-Thaumatodon group correlates with the
penial epiphallus grouping, and represents a major
change in structure. As an example of retaining a
marked pattern of variation through major shell size
and shape shifts, the very characteristic apertural
barriers of Anceyodonta also are seen in the Man-
garevan Minidonta and Gambiodonta. All the Man-
garevan taxa also have the tendency to develop
microdenticulated trace barriers (figs. 71c; 89d, f; 187).
Phylogenetic conclusions
The Pacific Island Endodontidae are characterized
by a repetitive set of conchological specializations that
have produced frequent convergences in appearance,
plus a few anatomical trends that do not correlate
with the basic conchological trends. If more taxa had
been available for dissection, particularly from areas
such as Mangareva and the Society Islands, the
number of identified anatomical trends undoubtedly
would have increased. My ideas concerning the
phylogeny of the Endodontidae are summarized in
Figures 57 and 58. The first is a typical phyletic tree
Q .'.•.•.•.•.•.•.•.•.•.•.•.•.•.
UILU U|
111
112
SOLEM: ENDODONTOID LAND SNAILS
diagram, while the second introduces additional data
concerning degree of relationships and patterns of
specialization. Detailed arguments concerning inter-
generic relationships are developed in the systematic
review and are not repeated here.
The first conclusion, shown in Figure 57, is that
Cookeconcha and Minidonta, although now showing
divergent patterns of structure, shared a direct
common ancestor and formed the stem groups for
subsequent evolution. That they are truly primitive in
all features is unlikely, since the unusual umbilical
decoiling pattern of many Minidonta (figs. 62c, f; 63b;
69c, f) and the bifid parietal of many Cookeconcha
represent highly atypical situations within the context
of the family. Nevertheless, their patterns of dis-
tribution and most structural features place them
perhaps nearest to the potential ancestral group of any
extant taxa. The Hawaiian radiation into Nesophila
and Endodonta is derived from Cookeconcha. Un-
doubtedly more generic level taxa will be delineated
when the Hawaiian fauna has been reviewed in detail.
Mautodontha, Australdonta, and Anceyodonta
represent separate specializations from the Minidonta
complex, each subsequently giving rise to other taxa.
The Society, Cook, and Tuamotu island Libera,
Kleokyphus, Nesodiscus, and Pseudolibera represent
local developments from subgenera of Mautodontha.
The Marquesan Taipidon also is derivable from very
generalized Mautodontha, but shows a variety of
specializations, one of which led to the endemic
Planudonta. All available data suggest that the Rapa
Island radiation is monophyletic, with Opanara repre-
senting the generalized condition from which Rhyso-
concha, Ruatara, Orangia, and Kondoconcha were
independently derived. Opanara more probably was
derived from a Mautodontha-type ancestor, but could
have evolved from a Minidonta-\eve\ ancestor of large
size. On Mangareva in the Gambler Islands, Rikitea
and Gambiodonta represent local derivates either
directly from the Minidonta stock or from Anceyo-
donta.
As outlined in the zoogeography section (pp. 488-
492), the Thaumatodon-Aaadonta complex has a very
different pattern of distribution from that shown by
the other taxa. It also shows significant changes in
structure. I regard it as being a more recent element in
the Pacific Island fauna, one that evolved from
endodontids formerly in the Indonesia-New Guinea-
Australia axis that are now extinct, their place having
been taken by the Charopidae. While Thaumatodon
and its derivatives share a distant common ancestry
with the other species groups, this complex probably is
not derived from any of the extant Pacific Island taxa,
but rather from extralimital groups. Although the
structures found in the Thaumatodon-Aaadonta
complex can be derived from those found in the
Mautodontha-level taxa, the discordance in dis-
tribution type is so large and the morphological gap so
abrupt that the hypothesis of an independent origin
followed by secondary colonization seems far more
probable to me.
A different approach is taken in Figure 58 which
indicates four levels of conchological specialization
that are in great part size correlated, presents
additional data about interrelationships of species
groups, summarizes size range within genera, and also
includes data on probable directions of evolution
within the group. One error resulting from lay-out
problems and one omission need to be mentioned.
Libera probably is derived from a Garrettoconcha-type
ancestor rather than Mautodontha, s. s., and Price-
concha should have been shown as coming from the
Thaumatodon stem as a "Nesodiscus level" taxon
right under the "Zyzzyxdonta" label. Inclusion of the
recently described Priceconcha would have required
redoing the entire chart.
A brief outline of the characteristics for each of
the four specialization levels follows. In increasing
order of specialization, they are the Minidonta,
Mautodontha, Nesodiscus, and brood-chamber levels.
Three genera are included on the Minidonta level.
These include the genus Rhysoconcha by secondary
derivation, the most generalized species group of
Cookeconcha (excluding C. nudus), and Minidonta
itself. As summarized in Table LXI, these species show
an average H/D ratio, but fall into the lower quartile
in both diameter and whorl count (cf. table LX). The
umbilicus is slightly narrower than average, relating to
both the low whorl count and the peculiar pattern of
umbilical decoiling seen in some Minidonta. All of
these taxa retain a prominent shell sculpture, and the
vast majority (16 of 21) have the aperture moderately
to strongly constricted by the barriers. Minidonta and
the most generalized Cookeconcha closely approach
each other in overall structure, but there are numer-
ous characters in which they contrast, as discussed
under Cookeconcha subpacificus on pp. 211-212. The
other Hawaiian genera are derivable from the general-
ized Cookeconcha, while the species groups within
Minidonta serve as effective stem groups for many
other taxa. Minidonta grades almost imperceptibly
into the Mangarevan Anceyodonta (pp. 179-181), while
Australdonta can be derived from the M. anatonuana
complex. The Rapan radiation could be descended
from either Minidonta or, more probably, the Mau-
todontha complex, as indicated by the dotted lines.
Mautodontha is, in itself, a stem group for a wide
variety of taxa. Estimating the exact relationships
between the more specialized Mautodontha-level taxa
and the species groups clustered as Minidonta is
hampered by the virtual lack of any anatomical data
for species in either Minidonta or Mautodontha. A
simpler classification would result if the geographical
species groups of Minidonta were associated with their
geographical derivatives, to form linear genera. I have
not done so, since the morphologic gap between the
derived genera and the Minidonta-species groups that
are logical ancestors to them usually is greater than
PHYLOGENY AND CLASSIFICATION
113
TABLE LXI. - SHELL PARAMETERS FOR LEVELS OF ORGANIZATION
Number of taxa
Minidonta
21
Mautodontha
111*
3.75 ±0.098
Nesodiscus
IT
Brood chamber
29
Diameter 2.25 ±0.095 3.75 ±0.098 5.90 ±0.538 5-39 ±0.277
(1.68-3.26) (1.87-8.99) (3.75-11.29) (U. 23-12. 26)
H/D ratio 0.5^5 ±0.010 0.528 ±0.009 0.1+1+9 ±0.016 0.597 ±0.012
(0.1+1+5-0.625) (0.3^-0.789) (0.31+6-0.560) (0. 1+80-0. 702)
Whorls 1+.83 ±0.12 5-1+9 ±0.06
(3-5/8 - 5-1/2+) (U-8)
D/U ratio 1+.87 ±0.39
(2.66-10.1)
the gaps between the species groups clustered within
Minidonta.
The Mautodontha level of organization contains
the bulk of the species and genera. They show the
median pattern in size, H/D ratio, and whorl count
(tables LX, LXI). Since species with closed umbilici
fall into this grouping, the mean D/U ratio was not
calculated. Currently, the stem genus, Mautodontha,
is virtually geographically isolated from Minidonta,
except for the joint occurrence on Raivavae in the
Austral Islands caused by the inclusion of Mau-
todontha ceuthma in that genus. This means that I
consider Mautodontha to be potentially a grade,
rather than a clade. With the lack of anatomical data
and limited material available, I have included M.
ceuthma in Mautodontha rather than with the
derivative Australdonta. Discussions of the derivation
patterns for Kleokyphus, Nesodiscus, Pseudolibera,
Libera, Taipidon, and Australdonta are discussed
under the respective genera. Several groups show
general trends toward, or include species that actually
have reached, the more specialized levels. For example,
Taipidon semimarsupialis has a definite brood cham-
ber, although no other member of the genus comes
close to attaining this level of specialization. In
contrast, while only Endodonta marsupialis has
secondary umbilical narrowing, most of the other taxa
have a U-shaped, deep umbilicus and are perfectly
"pre-adapted" to a narrowing trend. Kleokyphus from
Makatea and Kondoconcha from Rapa also are close
to this specialization pattern. Yet another taxon,
Thaumatodon euaensis, also shows umbilical narrow-
ing, but never had enough umbilical expansion to
justify calling this a brood chamber development.
Australdonta pharcata, A. ectopia, Opanara m.
megomphala, and O. m. tepiahuensis are Mau-
todontha-level taxa that show or approach the
Nesodiscus pattern of specialization.
The Nesodiscus-\eve\ genera, Nesophila, Neso-
discus, Planudonta, and Priceconcha are quite
strongly characterized. There is a gross reduction in
6.1+0 ±0.19 6.78 ±0.11
(U-7/8 - 7-3/8) (5-3/8 - 8+)
2.21+ ±0.10
(1.68-3.11+)
sculptural prominence (less in Planudonta), usually
great-to-complete reduction in the apertural barriers, a
sharp increase in diameter (table LXI) accompanied
by an extremely widely open umbilicus, a whorl count
mostly in the upper quartile, but also a lower quartile
H/D ratio. These species have increased their whorl
count in regular fashion, but with umbilical widening
not followed by a change in growth vectors to produce
either a brood chamber or a very high spire. The
trends to sculpture reduction and loss or reduction of
the apertural barriers are quite consistent and contrast
with the pattern in the brood-chamber taxa, where
sculpture reduction is much less frequent and the size
reduction in the parietal barriers far less accentuated.
The method of sculpture reduction also differs. In the
Nesodiscus level this occurs first by multiplication of
rib numbers and crowding, followed by their loss
(except in Planudonta). In brood-chamber taxa rib loss
occurs by gradual size reduction in the major ribs,
rather than multiplication, then loss. In calculating
the averages for the Nesodiscus level, I omitted the
Australdonta and Opanara species listed above, since
they agree only with part of the character complex.
One additional genus requires comment. The very
poorly known Mangarevan taxon Rikitea has the
shape and growth pattern of the Nesodiscus special-
ization, but differs quite obviously in retaining a very
large parietal barrier and prominent radial ribbing.
The two Australdonta (fig. 137) come much closer to
reaching "Nesodiscus status."
The brood-chamber taxa, Libera, Gambiodonta,
Pseudolibera, Endodonta marsupialis, and Taipidon
semimarsupialis, show a continued increase in whorl
count, an H/D ratio in the upper quartile, and a lower
diameter than the Nesodiscus-level taxa. These are
functional requirements of this level, since secondary
narrowing of the brood chamber necessitates shifting
growth vectors to increase the shell height and lessen
the diameter. Their retention of strong sculpture and
prominent apertural barriers, in contrast to the
Nesodiscus series, suggests that these represent paral-
lel rather than sequential stages. While umbilical
114
SOLEM: ENDODONTOID LAND SNAILS
widening in the Nesodiscus pattern is a mandatory
prelude to secondary narrowing and brood chamber
formation, the derivation of Nesodiscus from a species
very similar to Mautodontha boraborensis is discussed
below (p. 345) and the derivation of Libera from
the subgenus Garrettoconcha (p. 165) hints at the
contrasting patterns. Whether the sculpture reduction,
barrier reduction and continued umbilical widening of
the Nesodiscus are genetically linked in a formal sense
or became linked in a channeled development pattern
is unknown. It is probable, however, that no Neso-
discus-level taxon would alter its pattern to shift into
the U-shaped and then narrowed umbilicus seen in
brood-chamber taxa. In contrast, the tendency of
many Mautodontha-leve\ taxa to form U-shaped
umbilici while retaining heavy sculpture and promi-
nent barriers suggests that there is more than chance
to these divergent patterns.
Most detailed discussion of phylogeny in the
systematic review is based on geographic lineages, since
the patterns in variation of the apertural barriers and
anatomy that are not size correlated clearly link
together the taxa from each island group. For example,
in the Hawaiian genera there are the common patterns
of bifidity in the barriers, shift in radular tooth shape,
and standard penis structure; the Mangarevan taxa
have a characteristic tooth structure that encompasses
all material except the peculiar Rikitea; the Marque-
san genera have the altered penis structure; and the
Thaumatodon-Aaadonta complex has not only the
altered penis but also the very striking change in
barrier expanded surfaces. The convergences in the
shell size, shape, and sculpture that mostly correlate
with size factors are extensive enough that they
swamp the few factors used to establish phyletic
affinity if all are tossed into a phenetic program.
During the middle portion of this study, I was
able to have data on the shell variables put through
both the "minimum steps" and Sharrock-Felsenstein
"combinatorial" programs for computing phylogenies.
Forty-seven meristic or structural features were coded
and directional changes from the postulated "general-
ized" condition indicated. The computer programs
available for use at that time required data on every
species for each character used, which effectively
eliminated using any anatomical data, and could
handle only 25 taxa at a time. The characters used
were the shell features discussed above (pp. 19-72). The
only difference was that my analysis of the ways in
which the same state could be achieved independently
had not been carried nearly as far, nor were character
correlations as fully understood. As would be expected,
the programs separated out highly differentiated taxa,
such as distinguishing between Thaumatodon, Aaa-
5 10 11 12 9
13 14 15
16 17
ancestor
ancestor
Fu;. 59. Computer generated phylogeny, "combinatorial" method, of Thaumatodon, Zyzzyxdonta, and Aaadonta. Derivation from
left to right in sequence. Extant species are: 1) Thaumatodon multilamellata; 2) T. decemplicata; 3) T. laddi; 4) T. subdaedalea; 5) T.
corrugata; 6) T. hystricelloides; 7) T. vavauensis; 8) T. euaensis; 9) Zyzzyxdonta alata; 10) Aaadonta pelewana; 11) A. f. fuscozonata;
12) A. f. depressa; 13) A. kinlochi; 14) A. irregularis; 15) A. c. komahanensis; 16) A. c. babelthuapi; 17) A. c. constricta; 18) A.
angaurana. Small numbers are Thaumatodon; large numbers Aaadonta; bold face Zyzzyxdonta. a and 6 represent different computer
runs.
me
HI?
OJ
CJ
o
OJ
^3 LT . O QO
Hill
S •• 9* Si (™\
«
£ '."
i'^JI*
§£.00
S«
•JPt: S « ^ a
C c-i 5 -H N .Q
H
115
116
SOLEM: ENDODONTOID LAND SNAILS
donta, and Zyzzyxdonta (fig. 59), but when presented
with somewhat similar taxa from different islands,
such as Orangia, Opanara, and Rhysoconcha from
Rapa, plus Taipidon from the Marquesas (fig. 60), or
Mlnidonta, Mautodontha, and Cookeconcha subpa-
cificus (fig. 61), the results were less satisfactory.
The differentiated taxa run (fig. 59) had Zyzzyx-
donta (species 9) from Fiji associated with Aaadonta
kinlochi (species 13) from Palau. Both species are low-
spired, carinated, and show quite different proportions
from typical members of either genus. Different
computer runs (fig. 59a, b) give different results. A.
angaurana (species 18) could be associated with either
A. c. constricta (species 17 in fig. 59a) or A. irregularis
(species 14 in fig. 59b). Both runs mixed up the
Thaumatodon geographically, grouping Fiji (3) and
Ellice (2), Samoa (6) and Tonga (7) in Figure 59a, and
partly in Figure 59b. Both runs segregated the races of
Aaadonta constricta and recognized A. pelewana and
A. fuscozonata as a monophyletic assemblage.
The Taipidon and generalized Rapa Island taxa
(fig. 60a, b) included only situations where the genera
are very well differentiated by anatomical criteria. The
shells show a wide variety of convergences. In the
absence of anatomical data it would be unreasonable
to expect that the computer would avoid confusing
convergence with phyletic affinity. It did not. Linking
Opanara megomphala (species 12) with Taipidon
centadentata (species 8 in fig. 60b) is quite logical on
overall appearance, provided no anatomical data is
available.
The extensive mixing of geographic and generic
groups in the Minidonta-Mautodontha run (fig. 61)
requires no commentary. What is intriguing in this
phylogeny is the placement of Cookeconcha subpa-
cificus (species 1) in basal position, the grouping of
Kleokyphus (species 24, 25) as highly specialized taxa,
and the two peculiar Aitutaki species (13, 23) as highly
derived taxa sharing many similarities.
Shell data alone, particularly when convergent
variations are not carefully screened out, are quite
inadequate to permit obtaining "good phylogenies" in
the Endodontidae by computer analysis. The fault lies
not with the computer, but with the subtle and
repetitive nature of the variations. The island dis-
tributions were an incalculably great aid to this study.
If a continental pattern had been involved, I doubt
very much that I would have been able to recognize
patterns so clearly. The results of both the
conventional and computer studies do emphasize the
need to understand the functional significance of
character variation and to weight the variations
accordingly. The computer is an invaluable tool in
sorting taxa, suggesting possible relationships, empha-
sizing convergences, and forcing one to examine and
analyze far more data than previously. But it is no
substitute for the more conventional approaches used
here.
The above discussion completes the tentative
review of endodontid phylogeny. As a final and totally
subjective comment, there are geographical "styles" of
variation. While the Mangarevan and Society Islands
differentiations into more specialized levels are "ma-
ture" in character, the Marquesan experiments into
brood chamber and Nesodiscus level seem tentative
and "juvenile." The end results were achieved in
Taipidon semimarsupialis and Planudonta, respective-
ly, but in far less polished ways than is shown by the
other groups. The Hawaiian taxa show almost an
exuberant pattern of minor experimentations, which is
equalled by Thaumatodon and its derivatives in the
Lau Archipelago of Fiji. In contrast, the divergence of
Aaadonta in Palau shows only minor variations on a
theme, while on Rapa there has been variation more in
anatomy than shell structure. Quite possibly this is a
function of island age and time of colonization, but
such zoogeographic topics are deferred.
FOSSIL ENDODONTOID LAND SNAILS
In favorable circumstances, fossils can yield data
that are crucial to interpreting phylogeny and estimat-
ing rates of evolution. Unfortunately, the fossil
endodontoid land snails (Ladd, 1958, 1968; Ladd et al.,
1967, 1970) add details rather than providing major
input. At present there are six taxa known, two
charopids, "Ptychodon" eniwetokensis Ladd (1958) and
"P." davidi Ladd (1968), two endodontids that are
reviewed below (Minidonta inexpectans, p. 132, and
Cookeconcha subpacificus, p. 212), and two unde-
scribed species from the core drillings on Midway.
These range in age from Lower Miocene to Late
Pleistocene or Recent. They are discussed in order of
decreasing age. The oldest species, Cookeconcha sub-
pacificus from the Lower Miocene of Bikini Atoll at
1,807-1,818 ft. is based on a fragmentary specimen that
agrees most closely with the Cookeconcha henshawi
group (p. 213). None of the preserved features on this
shell are inconsistent with extending Cookeconcha
back to the Lower Miocene and from the present
Hawaiian range to include the Marshall Islands.
"Ptychodon" eniwetokensis, from the Upper Miocene
of Eniwetok at 820-831 ft., also is based on a
fragmentary example, but the available features place
it in a relatively advanced genus (undescribed) of the
Charopidae. The Eniwetok fossil agrees more with
extant congeneric taxa from Niue and Vaitupu in the
Ellice Islands than with the species from Fiji and
Tonga. The latter are more specialized in structure.
The three more generalized taxa thus form a rough
fringing pattern of distribution within the genus. The
range extension from Vaitupu to Eniwetok is not very
significant in terms of geography, although placing the
fringe distribution in an Upper Miocene context has
some importance. The Pliocene to Pleistocene Min-
idonta inexpectans from Bikini at the 447-453 ft. level
is very close to the recent Samoan Minidonta
manuaensis (pp. 130-132). Together with Minidonta
IDi
12
||LO
\
o
v>
c_>
cr
CO
III
<N «
s .5 ~
S . . aT
•N^^
2 ? "3
-^ i3
s ^ «
° ^ JD
CO
117
118
SOLEM: ENDODONTOID LAND SNAILS
micro from Mangareva and M. hendersoni from
Henderson Island, they form the most generalized
group of Minidonta and also show a fringing dis-
tribution pattern to the other Minidonta. The range
extension of Minidonta from its current western limits
of American Samoa to Bikini is a major geographic
extension. Several specimens of this species were
available and the concurrence with M. manuaensis is
very strong.
The two morphotypes from Midway Atoll, found
in the upper levels of both cores, are Pleistocene in age
(Ladd et al., 1970, p. A16). One specimen is clearly a
Cookeconcha and eight specimens belong to a distinct
genus that is intermediate between the characters of
Cookeconcha and Endodonta. The above comments
are based on personal examination of this material.
The existence of a varied endodontid fauna on Midway
when it was an elevated island is not unexpected. The
probability that one form is generically distinct should
not be given any great importance, since the generic
limits used for Hawaiian species in this report are not
intended to be definitive. Undescribed species of
endodontids from the other Hawaiian Islands also
show intermediate conditions between Endodonta and
Cookeconcha.
"Ptychodon" davidi (Ladd, 1968) belongs to a
charopid genus (undescribed) that is represented by
two species from Fiji, two from the Bismarcks, and a
single species that has been found in West Irian,
Misool, Biak, Aru Islands, Timor, and Ambon. The
Funafuti Atoll Pleistocene to Recent fossil, from the
166-170 ft. level, is only very weakly differentiated
from one of the extant Fijian species.
The fossils thus take extant generalized and
specialized genera back to the Miocene, demonstrate
the presence of endodontids and charopids in the
Marshall Islands when they were high islands, and
suggest that the range of both Minidonta and
Cookeconcha have shrunk because of extinction as the
former high islands of the Marshall chain became low
atolls. Evidence that Bikini and Eniwetok formerly
were high islands with upland forest is presented by
Leopold (1969). More detailed consideration of the
distributional and historical data is deferred until the
second monograph.
PREVIOUS GENERIC CLASSIFICATIONS
The general similarity in shells of the endodontoid
taxa, based on their prominent radial ribbing, often
flammulated color pattern, and simple helicoid form
led most early authors to group known forms into
almost a Linnean genus (see Eyryomphala in Beck,
1837, pp. 8-9). Albers (1850, pp. 64-65, 89) grouped
most species under Patula, although describing Endo-
donta, while H. Adams and A. Adams (1854-1858, pp.
113-114) placed the Holarctic species in Discus and the
various Pacific Basin taxa into Pitys (which is now
restricted to an endemic Rapan tornatellinid, see
Cooke and Kondo, 1960). The second edition of Albers
(1860, pp. 59-63, 82, 85-91, 100), edited by von Martens,
established most of the classic divisions. Amphidoxa
and Stephanoda were proposed for the Juan Fernan-
dez and South American species; Charopa and
Thalassia for New Zealand and Australian species;
Endodonta continued to be used for the Pacific Island
species with apertural barriers; while Patula and
Discus were grouped with Trochomorpha as barrierless
taxa.
The first catalogue of Pacific Island land snails
(Pease, 1871a, pp. 474-475) used Endodonta for large,
carinated species with apertural barriers, and Pitys for
small species, with and without barriers. This was a
period of great descriptive activity in terms of species
(table III), but great conservatism in terms of generic
units. Garrett (1881) proposed Libera for brood-
chamber taxa, used Patula for taxa with only one
barrier or no barriers, and later (Garrett, 1884) used a
heirarchy based on barriers and shell shape. His
system was:
Barriers in aperture
Periphery carinated — Endodonta
Periphery rounded — Pitys
Umbilical brood chamber — Libera
No barriers in aperture — Patula
Tryon (1887, pp. 59-72) used Endodonta and Libera as
"sections" of his broadly defined genus Helix.
Pilsbry (1893-1895, pp. 6-54) summarized the
endodontoids in a critical checklist, recognizing as full
genera in the Endodontidae Punctum, Laoma,
Flammulina, Endodonta, Phasis, Amphidoxa, Pyrami-
dula, and Pararhytida. All of the Pacific Island taxa
were distributed among various subgenera and sections
of Endodonta. This was a compilation needed to
complete his checklist and revision of the helicoid taxa,
but included virtually no original observations. His
rationale for division of Endodonta, ignoring those
taxa erroneously included, was:
Barriers in aperture
Umbilical brood chamber — Subgenus Libera
No umbilical brood chamber
St. Helena Island — Section Helenoconcha Pilsbry, 1892
New Zealand — Polynesia
Periphery keeled — Section Endodonta
Periphery rounded
Palatal wall without barriers — Section Nesophila
Pilsbry, 1893
Palatal wall with barriers
New Zealand — Section Ptychodon Ancey, 1889
Polynesia — Section Thaumatodon Pilsbry, 1893
No barriers in aperture — Subgenus Charopa and various New
Zealand taxa
Pilsbry (1893-1895, p. 21) recognized the pattern of
tooth loss, but commented "The distinction between
Charopa and Endodonta is of little value, on account
of the degeneration of the teeth ( = barriers) in some
forms of the latter, producing species which technical-
ly fall under the former group." Except for nomencla-
tural changes, his system was only an extension of
PHYLOGENY AND CLASSIFICATION
119
that proposed by Garrett (1884), although Pilsbry did
recognize higher level dichotomies (pp. 105-106). This
is one of the very few examples where Pilsbry
summarized a group without making fundamental
modifications in the classifications.
Subsequently, Thiele (1931, pp. 569-575) recog-
nized 25 genera in the Subfamily Endodontinae. I
retain parts of only four genera in the restricted
Endodontidae. Most others belong to the Charopidae.
Ptychodon was used by Thiele for taxa with a rounded
periphery and barriers (including Nesophila and
Thaumatodon as sections), Endodonta for carinated
shells with apertural barriers from the Hawaiian
Islands, and Libera (under a substitute name Garret-
tina) for brood-chamber taxa. He proposed a new
genus, Nesodiscus, for N. fabrefactus (Pease, 1864), the
only completely barrier-free endodontid, which also is
very unusual in its shape, has an extremely wide
umbilicus, and a total lack of shell sculpture. Zilch
(1959-1960, pp. 211-216) essentially copied Thiele's
classification.
Up to now, the classification scheme consisted of
using the barrier and periphery pigeonholes proposed
by Garrett (1881, 1884). In the absence of anatomical
data and critical analysis of the shell structures, no
meaningful alternative option was available. It does
mean that only five generic names are available for
use. In order of priority they are: Endodonta Albers
(1850), Libera Garrett (1881), Thaumatodon Pilsbry
(1893), Nesophila Pilsbry (1893), and Nesodiscus
Thiele (1931).
PROPOSED GENERIC CLASSIFICATION
Most classifications are a compromise between
user utility, making identification simpler, and an
attempt to express the postulated lines of phylogeny.
Given the same phylogenetic scheme, particularly if it
is at all complex, equally competent systematists will
derive slightly to grossly different schemes of clas-
sification. The question is partly whether to recognize
broadly drawn or narrowly defined genera. Any
classification usually is influenced by the inherent
conservatism of systematists. If a genus has been
proposed and used for a period of time, there is great
inertia against making a change in its status. Because
of the few available names and obvious artificiality of
the extant classification, this problem did not exist for
the Endodontidae and Pacific Island Charopidae.
Mostly the problem is that classifications present neat
dichotomies, while evolution is messy.
A major concern has been to try and establish
comparability of generic units, to make "generic level
differentiation" represent a roughly equivalent degree
of change throughout the family. This is, of course,
virtually impossible to attain, since there will be
differences in the phylogenetic and morphologic gaps
between species clusters. As in distinguishing species, it
is possible to establish minimum distance, but it was
not feasible to establish a set of mathematical criteria
to delimit a range of difference levels between species
clusters. In some cases data were lacking. In reviewing
the Hawaiian fauna, I deliberately used far broader
generic units than elsewhere in this monograph, simply
because the Hawaiian fauna was surveyed cursively,
although material for a critical revision is available in
the Bishop Museum. Refinement of the Hawaiian
endodontid classification and phylogeny is left to
others.
My actual criteria have depended on the clusters
concerned. They also involve the degree of
morphologic gap between clusters as they relate to the
four levels of specialization and/or anatomical
changes. In many situations clear phylogenetic gaps
exist, but there are situations in which a virtually
continuous series exists between end points that show
"generic level differences" (Minidonta and Anceyo-
donta). In other situations, a single species might have
specializations of a different level of organization, but
retains so many features common to the stem complex
that retention within that genus seems preferable. In
a real sense, the classification proposed is thus a
continuous series of compromises between phyletic
lines, degree of morphologic gaps, overall similarity,
importance assigned to structural differences within
each unit, and, perhaps most important, what I
consider to be the current evolutionary stages and
potentials of the species clusters.
A few examples will serve to illustrate the way in
which these criteria were applied. The brood-chamber
taxa Libera, Gambiodonta, and Pseudolibera show
major size and structural differences from taxa that
apparently are ancestral. No confusion of these derived
genera with Mautodontha, Minidonta, and Mau-
todontha or Kleokyphus, respectively, is possible. The
former show a clearly defined and substantial "degree
of difference." In the Society Islands, Mautodontha
boraborensis (Garrett, 1884) shows the trends needed
to advance from Mautodontha into Nesodiscus, but (p.
153) retains enough Mautodontha characteristics to fit
more comfortably into that genus. Logically it could
be classified in either. On the Marquesan Islands,
Taipidon and Planudonta share anatomical features
that are not found elsewhere in the family (p. 315).
They obviously shared common ancestry, with Plan-
udonta being derivable from Taipidon by undergoing
"Nesodiscus specializations." The increased whorl
count, widened umbilicus, and dramatically reduced
size of the apertural barriers in Planudonta when
compared with Taipidon are typical "Nesodiscus
specializations." They result in a wide enough
"morphologic gap" to warrant generic separation, even
though there is no sculpture reduction. In contrast,
Taipidon semimarsupialis has achieved brood-cham-
ber formation in a rather crude way (in terms of
complexity of morphological changes). In virtually
every character except whorl number and a very
120
SOLEM: ENDODONTOID LAND SNAILS
inelegant secondary umbilical narrowing, T. semi-
marsupialis is a Taipidon.
The Rapan taxa illustrate classification problems
within a specialization level. Rhysoconcha differs in its
secondary size reduction; Ruatara shows a major
change in penial structure, whorl count, and growth
pattern; Kondoconcha differs in several features from
the basic Opanara pattern; and Orangia shows more
conchological than anatomical changes. The average
pattern within each genus is clearly different from
that found within the others, and there is very little
evidence of intergradation. The differences between
these genera are of the same order of magnitude as are
those between Australdonta, Mautodontha, Taipidon,
Kleokyphus, and Anceyodonta, other genera at the
Mautodontha level of specialization.
Cookeconcha and Minidonta approach each other
rather closely, although retaining patterns of differ-
ence, but Minidonta and Anceyodonta blend almost
insensibly on Mangareva. While typical Anceyodonta
is a quite well characterized genus on the Mau-
todontha level, the fusion between the less specialized
species and Minidonta only shows that evolution was
in progress. Description of Anceyodonta and making
an arbitrary (p. 179) dividing line between it and
Minidonta focuses on the advanced Anceyodonta far
more effectively than would inclusion of all species in
Minidonta or the use of subgenus.
Division of the Thaumatodon complex into gen-
era, by contrast, presented few problems. Thaumato-
don has the most typically endodontid shell structure,
although the T. hystricelloides complex shows sig-
nificant variations. Aaadonta differs in penial pilaster
pattern, but most strikingly in shell-sculpture reduc-
tion and shell shape. Priceconcha is modified in
habitat (tree trunk), shell form (Nesodiscus pattern),
and sculpture, while Zyzzyxdonta has major shape and
TABLE LXII. - FREQUENCY DISTRIBUTION OF SPECIES/GENUS
IN PACIFIC ISLAND EHDODONTOIDS
Number of genera in:
Punctidae and
Charopidae
10
14
It
2
Species level taxa
in genus Endodontidae
1 5
2 2
3-5 1*
6-9 It
10-15 6
16-19 3
over 50 - 1
Total species level taxa
in family 185 98
sculpture alterations. The differences are more
obvious, but perhaps no more significant than are
those seen in the Rapan radiation.
Such differences in "phyletic distance" are inevi-
table when a two-dimensional static system attempts
to circumscribe evolutionary progress at a single time
moment. The attempt to make generic units
comparable through establishing a minimum phyletic
distance as warranting generic recognition, leaves the
maximal phyletic distance unspecified and totally
ignores the question of how many species are in each
genus. For the Pacific Island taxa, the number of
species per genus frequency is tallied in Table LXII.
The high number of monotypic genera in the Charo-
pidae and presence of a single highly speciose genus in
that family contrasts with a more even distribution in
the Endodontidae. This reflects different patterns of
evolution in the two families and will be considered in
the zoogeographic portion of the second monograph.
SYSTEMATIC REVIEW
FAMILY ENDODONTIDAE
Small to large endodontoids at least primitively with prominent
radial sculpture on both apex and lower whorls, sculpture often
becoming reduced or lost in larger species. Microsculpture of radial
riblets and primitively of microspiral "squiggly" cords that are lower
than the microradials, with most sculpture formed by calcareous
layers under a periostracal template, except for periostracal setae
and rib peak extensions. Whorls in adults 3'/2-9, coiled with
varying degrees of spiral protrusion or depression, umbilicus generally
widely open, regularly decoiling and used as an egg deposition site. In
many taxa whorl count increased and umbilical cavity secondarily
narrowed to form a nearly enclosed brood chamber for the eggs.
Color generally flammulated with alternating irregular reddish and
yellow brown markings. Aperture of shell primitively with high and
complex barriers on all walls, posterior elevated portions of barriers
expanded and capped with triangular microdenticulations that point
toward the apertural opening. Barriers reduced in many taxa, absent
only in one. Foot of animal undivided, prominent pedal and
suprapedal grooves present that unite above tail, but without caudal
horn or enlarged mucus pore. Radula with tricuspid central,
primitively 5 to 6 bicuspid laterals, and 8-14 short, broad marginals
usually with split ectocones, tooth numbers increased in a few taxa.
Rest of digestive tract without unusual features. Pallial complex
with kidney reaching hindgut and having a weak rectal lobe, primary
ureter well developed and slightly reflexed at posterior, but opening
directly into pallial cavity without trace of groove or channel to
pneumostome. Mantle collar without lobes or shell laps. Genitalia
with following diagnostic features: ovotestis with multiple palmately
clavate clumps angled to shell axis; hermaphroditic duct normally
without coiling; talon with elongately oval head on a variable
lengthened shaft; prostate and uterus completely separate tubes,
alveoli of prostate large and thick, usually arranged in rows opening
into duct; vas deferens normally opening through a simple pore
subapically on penis, in one lineage with altered opening into a
penial epiphallus; penis primitively with two longitudinal pilasters,
variously modified under conditions of sympatry and with minor
added structures in some lineages, but never with a verge or vergic
papilla; free oviduct a simple tube that may or may not unite with
spermathecal shaft before atrium; spermatheca with ovate head
lying above pallial cavity apex, shaft inserting onto free oviduct,
atrium, or base of penis; penial retractor muscle originating from
columellar retractor or diaphragm, inserting variously on penis head
or side; penis enervated from right cerebral ganglion.
Of the genera that have been dissected, the
compact group of Thaumatodon, Aaadonta, Price -
concha, and Zyzzyxdonta is the most distinctive. The
degree of difference, however, is not great enough to
warrant subfamily recognition, or possibly even "trib-
al" or any equivalent intermediate status. Since the
subfamily divisions in the Charopidae still remain
undefined, I defer assigning any formal rank to this
group of genera. I simply wish to emphasize again that
they are the most strongly differentiated endodontid
taxa in terms of phyletic position.
The order in which genera are discussed in any
monograph must be an unsatisfactory compromise
between goals of phyletic order, structural similarity,
user convenience, and faunistic unity. The sequence
adopted here arbitrarily places the specialized Thau-
matodon-Aaadonta complex last, while ordering the
remaining genera roughly as to their level of special-
ization. Since some genera span two levels, this
introduces immediate distortion. Geographic and phy-
letic unity has been partly sacrificed for clustering
morphologically similar taxa together. The first five
genera include the basic Minidonta and Cookeconcha,
plus three relatively generalized derivatives from
Minidonta— the Mangarevan Anceyodonta, the ba-
sically Cook and Society Island Mautodontha, and the
Makatea Island endemic Kleokyphus. Since Cook-
econcha contains many altered species, it and the
relatively specialized Kleokyphus are placed after the
others. The monophyletic Rapan radiation— Opanara,
Rhysoconcha, Ruatara, Orangia, and
Kondoconcha— follow, except for the latter which is
grouped with the conchologically similar Endodonta
for ease in comparison. Australdonta and Taipidon are
equivalent derivatives and somewhat similar to
Orangia. Hence these three genera are clustered
together.
Planudonta is a local derivative of Taipidon, and
together with Rikitea, Nesodiscus, and Nesophila,
form a distinctive level of specialization. Kondoconcha
and Endodonta are pre-"brood chamber" special-
izations, and thus precede Pseudolibera, Libera, and
Gambiodonta.
Thaumatodon, Priceconcha, and Zyzzyxdonta,
which form a monophyletic series from Polynesia and
its western fringes, precede Aaadonta, the only
Micronesian endodontid group.
The function of keys is to facilitate identifications.
Because of extensive convergence in shell features, and
the probable future unavailability of preserved soft
parts, any phyletic key would be unusable. Any
artificial key to genera would involve so many
multiple entries as to be unwieldy. As a functional
compromise, keys are presented only to genera from
limited geographic areas. Since the shells will continue
to be confused, these keys include couplets sorting out
charopid taxa from the endodontids where applicable.
121
122
SOLEM: ENDODONTOID LAND SNAILS
Keys to the charopid genera and species must be
deferred until the second monograph, however, since
virtually all of the generic names are new.
Under each species, the following format has been
adopted. First, a diagnosis summarizes the observed
range of variation in high-information shell features
for all material studied. This is followed by a short
paragraph of comparative remarks that summarizes
"key character" differences from those taxa with which
it is most likely to be confused. A description of the
nomenclatural type specimen follows, which includes
the only data presented on color patterns. Information
on the holotype location, geographic range, paratypes,
and list of material studied precedes a usually short
discussion on local variation or morphological deviants
observed within that species or subspecies. When
available, description of anatomical features completes
the treatment of the species.
Presentation of both a diagnosis and a description
is done with reluctance, but out of necessity. Partic-
ularly for taxa from areas such as the Palau, Society,
Austral, Gambier, and Marquesan Islands, the species
limits presented here often include populations
showing noticeable differences. While currently limited
material has led me to propose including them under a
single name, I will not be in the least surprised if a
number of these prove to be compound taxa. Too
much detailed work in the last few decades has
revealed the complexity of island speciation patterns
and the narrowness of morphological differences for
me to think otherwise. A "lumper" by both philosophy
and training, I have preferred to err on making species
limits too broad rather than to subdivide on in-
complete evidence. But this does impose on me an
obligation to establish unequivocally what is intended
as the name-bearing part of the morphologic range.
The designation of specified stations does this in part,
but both the illustration (usually) of the "holotype"
and presentation of a type description will greatly
simplify future work.
Illustrations usually include only a side and
bottom view of the shell (since the coiling pattern
varies only slightly), sometimes a detailed view of the
aperture, and whatever part of the soft anatomy could
be depicted. In a few cases, unusual shell variants are
illustrated. For most Hawaiian taxa no shells have
been depicted. Through use of the keys and illustra-
tions species can be identified readily, but usually
averaged measurements will be needed.
Discussion of variational trends within genera and
relationships between species have been combined at
the beginning of each genus to save space and avoid
repetition.
LIST OF THE TAXA
Genus Minidonta, new genus
Minidonta manuaensis, new species — American Samoa: Manua
Group, Olosega and Ta'u
Minidonta inex.pecta.ns (Ladd, 1958) — Marshall Islands: Bikini
(fossil)
Minidonta micro, new species (Solem & Cooke) — Gambier Islands:
Mangareva
Minidonta hendersoni, new species (Cooke & Solem) — Henderson
Island
Minidonta micraconica, new species — Austral Islands: Raivavae
Minidonta gravacosta, new species — Austral Islands: Raivavae
Minidonta rotellina (Pease, 1870) — Cook Islands: Aitutaki
Minidonta anatonuana, new species — Austral Islands: Raivavae
Minidonta sulcata, new species — Austral Islands: Raivavae
Minidonta haplaenopla, new species — Austral Islands: Rurutu
Minidonta planulata, new species — Austral Islands: Raivavae
Minidonta taunensis, new species — Gambier Islands: Mangareva
Minidonta taravensis, new species (Solem & Cooke) — Gambier
Islands: Mangareva
Minidonta simulata, new species (Solem & Cooke) — Gambier
Islands: Mangareva
Minidonta extraria, new species (Cooke & Solem) — Gambier
Islands: Mangareva
Genus Mautodontha, new genus
Mautodontha (M.) boraborensis (Garrett, 1884) — Society Islands:
Borabora, 800-900 ft. elevation
Mautodontha (M.) daedalea (Gould, 1846) — Tuamotu Islands:
Makatea, Anaa and Niau
Mautodontha (M.) ceuthma, new species — Austral Islands:
Raivavae, Mt. Taraia
Mautodontha (M.) zimmermani, new species — Society Islands:
Tahiti, Mt. Aorai, 3,500-6,300 ft. elevation
Mautodontha (M.) zebrina (Garrett, 1874) — Cook Islands: Rar-
otonga
Mautodontha (M.) aoraiensis, new species — Society Islands: Tahiti,
Mt. Aorai, 4,700-5,500 ft. elevation
Mautodontha (Garretto concha) consobrina (Garrett, 1884) —
Society Islands: Huahine
Mautodontha (Garrettoconcha) saintjohni, new species — Society
Islands: Borabora, 800 ft. elevation
Mautodontha (Garrettoconcha) maupiensis (Garrett, 1872) —
Society Islands: Maupiti
Mautodontha (Garrettoconcha} punctiperforata (Garrett, 1884) —
Society Islands: Moorea
Mautodontha (Garrettoconcha) imperforata (Pease, 1870) — Cook
Islands: Aitutaki
Mautodontha (Garrettoconcha) parvidens (Pease, 1861) — Society
Islands: Tahiti, Moorea, and Huahine
Mautodontha (Garrettoconcha) subtilis (Garrett, 1884) — Society
Islands: Huahine
Mautodontha (Garrettoconcha) rarotongensis (Pease, 1870) — Cook
Islands: Atiu
Mautodontha (Garrettoconcha) consimilis (Pease, 1868) — Society
Islands: Raiatea
Mautodontha (Garrettoconcha) acuticosta (Garrett, 1884) — Society
Islands: Raiatea
Mautodontha (Garrettoconcha) unilamellata (Garrett, 1874) — Cook
Islands: Rarotonga
Genus Anceyodonta, new genus
Anceyodonta ganhutuensis, new species (Cooke & Solem) — Gambier
Islands: Mangareva
Anceyodonta subconica, new species (Solem & Cooke) — Gambier
Islands: Mangareva
Anceyodonta constricta, new species (Cooke & Solem) — Gambier
Islands: Mangareva
Anceyodonta andersoni, new species (Cooke & Solem) — Gambier
Islands: Mangareva
Anceyodonta alternata, new species (Cooke & Solem) — Gambier
Islands: Mangareva
Anceyodonta difficilis, new species — Gambier Islands: Mangareva
Anceyodonta soror, new species — Gambier Islands: Mangareva
Anceyodonta sexlamellata (Pfeiffer, 1845) — Gambier Islands:
Mangareva
SYSTEMATIC REVIEW
123
Anceyodonta densicostata, new species (Cooke & Solem) — Gambler
Islands: Mangareva
Anceyodonta obesa, new species — Gambier Islands: Mangareva
Anceyodonta labiosa, new species - Gambier Islands: Mangareva
Anceyodonta hamyana (Ancey, 1889) - Gambier Islands: Mang-
Genus Cookeconcha, new genus
Cookeconcha subpacificus (Ladd, 1958) - Marshall Islands: Bikini
(fossil)
Cookeconcha henshawi (Ancey, 1904) - Hawaiian Islands: Hawaii,
Hamakua slope of Mauna Kea
Cookeconcha cookei (Cockerell, 1933) - Hawaiian Islands: Oahu,
Mt. Tantalus
Cookeconcha thwingi (Ancey, 1904) — Hawaiian Islands: Hawaii,
Kona coast
Cookeconcha nudus (Ancey, 1899) — Hawaiian Islands: Hawaii
Cookeconcha contortus (Ferussac, 1824) — Hawaiian Islands: Oahu,
Waianae Mts.
Cookeconcha ringens (Sykes, 1896) — Hawaiian Islands: Lanai and
Molokai
Cookeconcha elisae (Ancey, 1889) — Unknown, probably Hawaiian
Islands
Cookeconcha luctiferus (Pilsbrv & Vanatta, 1905) — Hawaiian
Islands: Molokai
Cookeconcha hystricellus (Pfeiffer, 1859) — Hawaiian Islands: Oahu,
Waianae Mts.
Cookeconcha stellulus (Gould, 1844) — Hawaiian Islands: Maui
Cookeconcha paucicostatus (Pease, 1870) — Hawaiian Islands: Kauai
Cookeconcha paucilamellatus (Ancey, 1904) — Hawaiian Islands:
Hawaii
Cookeconcha thaanumi (Pilsbry & Vanatta, 1905) — Hawaiian
Islands: Maui, Hawaii, and Molokai
Cookeconcha hystrix (Pfeiffer, 1846) — Hawaiian Islands: Oahu
Cookeconcha decussatulus (Pease, 1866) — Hawaiian Islands: Maui
and Molokai
Cookeconcha lanaiensis (Sykes, 1896) — Hawaiian Islands: Lanai,
Hawaii and Kauai
Cookeconcha jugosus (Mighels, 1845) — Hawaiian Islands: Kauai
Genus Kleokyphus, new genus
Kleokyphus callimus, new species — Tuamotu Islands: Makatea
Kleokyphus hypsus, new species — Tuamotu Islands: Makatea
Genus Opanara, new genus
Opanara depasoapicata, new species — Austral Islands: Rapa, Mt.
Perahu at 1,200-1,500 ft. elevation
Opanara bitridentata, new species — Austral Islands: Rapa. Mt.
Perahu at 1,500-1,850 ft. elevation
Opanara duplicidentata, new species - Austral Islands: Rapa, Mt.
Perahu at 1,200-1,500 ft. elevation
Opanara areaensis areaensis, new species and subspecies — Austral
Islands: Rapa
Opanara areaensis densa, new subspecies — Austral Islands: Rapa,
800 ft. elevation
Opanara areaensis microtorma, new subspecies — Austral Islands:
Rapa, Mt. Perahu, 1,300-1,500 ft. elevation
Opanara caliculata, new species — Austral Islands: Rapa, Mt.
Perahu, 1,800-1,900 ft. elevation
Opanara altiapica, new species — Austral Islands: Rapa, Mt.
Mangaoa, 1,000-1,100 ft. elevation
Opanara megomphala megomphala, new species and subspecies —
Austral Islands: Rapa, 800 ft. elevation, N. W. of Tautautu,
Maitua, 500 ft. elevation
Opanara megomphala tepiahuensis, new subspecies — Austral
Islands: Rapa, Mt. Tepiahu, 550 ft. elevation
Opanara fosbergi, new species — Austral Islands: Rapa, Mt. Perahu,
1,500-1,900 ft. elevation
Opanara perahuensis, new species — Austral Islands: Rapa, Mt.
Perahu, 1,800-1,900 ft. elevation
Genus Rhysoconcha, new genus
Rhysoconcha variumbilicata, new species — Austral Islands: Rapa,
Mt. Mangaoa, 800-900 ft. elevation
Rhysoconcha atanuiensis, new species — Austral Islands: Rapa
Genus Ruatara, new genus
Ruatara koarana, new species — Austral Islands: Rapa, Oromange,
Mt. Koara, 800 ft. elevation
Ruatara oparica oparica (Anton, 1839) — Austral Islands: Rapa,
Mt. Tanga
Ruatara oparica normalis, new subspecies — Austral Islands: Rapa
Ruatara oparica reductidenta, new subsqecies — Austral Islands:
Rapa
Genus Orangia, new genus
Orangia cookei cookei, new species and subspecies — Austral Islands:
Rapa
Orangia cookei montana, new subspecies — Austral Islands: Rapa,
Mt. Perahu at 1,200-1,800 ft. elevation
Orangia cookei tautautuensis, new subspecies - Austral Islands:
Rapa, Mt. Tautautu, 750 ft. elevation
Orangia maituatensis, new species — Austral Islands: Rapa
Orangia sporadica, new species — Austral Islands: Rapa
Genus Australdonta, new genus
Australdonta pseudplanulata, new species — Austral Islands:
Rurutu
Australdonta rimatarana, new species — Austral Islands: Rimatara
Australdonta degagei (Garrett, 1879) - Cook Islands: Mauke.
Austral Islands: Rurutu and Rimatara
Australdonta tapina, new species - Austral Islands: Rurutu
Australdonta yoshii, new species — Austral Islands: Rurutu
Australdonta magnasulcata, new species — Austral Islands: Rurutu
Australdonta radiella radiella (Pfeiffer, 1846) - Austral Islands:
Tubuai
Australdonta radiella rurutuensis (Garrett, 1879) — Austral
Islands: Rurutu
Australdonta raivavaeana, new species — Austral Islands: Raivavae
Australdonta tubuaiana, new species — Austral Islands: Tubuai
Australdonta pharcata, new species — Austral Islands: Tubuai
Australdonta ectopia, new species — Austral Islands: Raivavae
Genus Taipidon, new genus
Taipidon petricola petricola, new species and subspecies — Mar-
quesas Islands: Hatutu
Taipidon petricola decora, new subspecies — Marquesas Islands:
Eiao
Taipidon octolamellata (Garrett, 1887) — Marquesas Islands: Hivaoa
Taipidon woapoensis (Garrett, 1887) - Marquesas Islands: Uapou
Taipidon marquesana (Garrett, 1887) — Marquesas Islands: Nuku-
hiva
Taipidon anceyana (Garrett, 1887) - Marquesas Islands: Hivaoa
Taipidon analogica (Pease, 1870) — Marquesas Islands (no exact
locality known)
Taipidon semimarsupialis, new species — Marquesas Islands:
Nukuhiva, Mt. Ooumu
Taipidon centadentata, new species — Marquesas Islands: Nukuhiva,
Mt. Ooumu
Taipidon varidentata, new species — Marquesas Islands: Hivaoa
Taipidon fragila, new species — Marquesas Islands: Hivaoa
Genus Planudonta, new genus
Planudonta subplanula, new species — Marquesas Islands: Nukuhiva
Planudonta intermedia, new species — Marquesas Islands: Nuku-
hiva, Mt. Ooumu
Planudonta concava, new species — Marquesas Islands: Nukuhiva,
Mt. Ooumu
Planudonta matauuna, new species — Marquesas Islands: Hivao-
Genus Rikitea, new genus
Rikitea insolens, new species (Cooke & Solem) — Gambier Islands:
Mangareva
124
SOLEM: ENDODONTOID LAND SNAILS
Genus Nesodiscus Thiele, 1931
Nesodiscus taneae (Garrett, 1872) - Society Islands: Maupiti and
Borabora
Nesodiscus huaheinensis ( Pfeiffer, 1853) — Society Islands: Huahine
Nesodiscus obolus (Gould, 1846) — Society Islands: Huahine and
Raiatea
Nesodiscus cretaceus (Garrett, 1884) — Society Islands: Borabora
at 600 ft. elevation
Nesodiscus fictus (Pease, 1864) - Society Islands: Tahaa
Nesodiscus fabrefactus (Pease, 1864) - Society Islands: Raiatea and
Tahaa
Nesodiscus fabrefactus var. piceus (Garrett, 1884) — Society Islands:
Raiatea
Nesodiscus magnificus, new species — Society Islands: Borabora,
800 ft. elevation
Genus Nesophila Pilsbry, 1893
Nesophila tiara (Mighels, 1845) — Hawaiian Islands: Kauai
Nesophila baldwini (Ancey, 1889) — Hawaiian Islands: Kauai
Nesophila distans (Pease, 1866) — Hawaiian Islands : Kauai
Nesophila capittata (Pease, 1866) — Hawaiian Islands: Kauai
Genus Kondoconcha, new genus
Kondoconcha othnius, new species — Austral Islands: Rapa
Genus Endodonta Albers, 1850
Endodonta ekahanuiensis, new species — Hawaiian Islands: Oahu,
Waianae Mts., Ekahanui Gulch
Endodonta binaria (Pfeiffer, 1856) — Hawaiian Islands: Kauai
Endodonta apiculata (Ancey, 1889) - Hawaiian Islands: Kauai
Endodonta rugata (Pease, 1866) — Hawaiian Islands: Maui
Endodonta laminata (Pease, 1866) — Hawaiian Islands: Kauai
Endodonta kamehameha (Pilsbry & Vanatta, 1906) - Hawaiian
Islands: Molokai
Endodonta concentrata (Pilsbry & Vanatta, 1906) - Hawaiian
Islands: Lanai
Endodonta lamellosa (Ferussac, 1824) — Hawaiian Islands: Oahu,
Koolau Mts.
Endodonta marsupialis (Pilsbry & Vanatta, 1906) — Hawaiian
Islands: Oahu, Koolau Mts., Mt. Tantalus
Endodonta fricki (Pfeiffer, 1858) — Hawaiian Islands: Oahu,
Waianae Mts.
Genus Pseudolibera, new genus
Pseudolibera lillianae, new species (Cooke & Solem) — Tuamotu
Islands: Makatea
Genus Libera Garrett, 1881
Libera micrasoma, new species — Society Islands: Tahiti, Mt. Aorai,
5,600-6,300 ft. elevation
Libera bursatella bursatella (Gould, 1846) - Society Islands: Tahiti,
Mt. Aorai, 4,700-7,300 ft. elevation
Libera bursatella orofenensis, new subspecies — Society Islands:
Tahiti, Mt. Orofena, 4,000-6,600 ft. elevation
Libera cookeana, new species - Society Islands: Tahiti, Mt. Aorai,
4,700-6,300 ft. elevation
Libera gregaria Garrett, 1884 - Society Islands: Moorea, southwest
Libera recedens Garrett, 1884 — Society Islands: Moorea, west side
Libera dubiosa (Ancey, 1889) - Society Islands: Moorea, north and
east sides
Libera spuria (Ancey, 1889) - Society Islands: probably Tahiti
Libera garrettiana, new species — Society Islands: Tahiti,
northwestern part
Libera umbilicata, new species - Society Islands: Tahiti, Mt.
Orofena, 4,500 ft. elevation
Libera retunsa (Pease, 1864) - Society Islands: Tahiti, south side
Libera streptaxon (Reeve, 1852) - Society Islands: probably Tahiti
Libera heynemanni (Pfeiffer, 1862) - Society Islands: probably
Tahiti
Libera incognata, new species — Society Islands: probably Tahiti
Libera jacquinoti (Pfeiffer, 1850) — Locality unknown
Libera fratercula fratercula (Pease, 1867) - Cook Islands: Aitutaki,
Atiu, Mauke, Mangaia Islands and satellite islets of Rarotonga
Libera fratercula rarotongensis, new subspecies — Cook Islands:
Rarotonga
Libera subcavernula (Tryon, 1887) — Cook Islands: Rarotonga,
mountain ravines
Libera tumuloides (Garrett, 1872) — Cook Islands: Rarotonga, one
inland locality
Genus Gambiodonta, new genus
Gambiodonta agakauitaiana, new species (Solem & Cooke) —
Gambier Islands: Mangareva
Gambiodonta pilsbryi pilsbryi, new species (Cooke & Solem) —
Gambier Islands: Mangareva
Gambiodonta pilsbryi aukenensis, new subspecies (Cooke & Solem)
— Gambier Islands: Mangareva
Gambiodonta mangarevana, new species (Solem & Cooke) —
Gambier Islands: Mangareva
Gambiodonta mirabilis, new species (Cooke & Solem) — Gambier
Islands: Mangareva
Gambiodonta tumida, new species (Cooke & Solem) — Gambier
Islands: Mangareva
Gambiodonta grandis, new species (Cooke & Solem) — Gambier
Islands: Mangareva
Genus Thaumatodon Pilsbry, 1893
Thaumatodon multilamellata (Garrett, 1872) — Cook Islands:
Rarotonga
Thaumatodon decemplicata (Mousson, 1873) — Ellice Islands:
Nukufetau and Vaitupu
Thaumatodon hystricelloides (Mousson, 1865) — Samoan Islands:
Upolu
Thaumatodon euaensis, new species — Tonga Islands: Eua
Thaumatodon uavauensis, new species — Tonga Islands: Vavau
Thaumatodon subdaedalea (Mousson, 1870) — Fiji Islands: Lau
Archipelago, Kimbombo, Mango, Vanua Mbalavu
Thaumatodon corrugata, new species — Fiji Islands: Lau Archi-
pelago, Mango
Thaumatodon laddi, new species — Fiji Islands: Lau Archipelago,
Wangava
Thaumatodon spirrhymatum Solem, 1973 — Fiji Islands: Lau
Archipelago, Thithia
Genus Priceconcha Solem, 1973
Priceconcha tuvuthaensis Solem, 1973 — Fiji Islands: Lau Archi-
pelago, Tuvutha
Genus Zyzzyxdonta, new genus
Zyzzyxdonta alata, new species — Fiji Islands: Lau Archipelago,
Yangasa Cluster, Navutu-I-Loma
Genus Aaadonta, new genus
Aaadonta constricta constricta (Semper, 1874) — Palau Islands:
Peleliu
Aaadonta constricta babelthuapi, new subspecies — Palau Islands:
Babelthuap, Ngemelis
Aaadonta constricta komakanensis, new subspecies — Palau Islands:
Koror
Aaadonta fuscozonata fuscozonata (Beddome, 1889) — Palau
Islands: Koror
Aaadonta fuscozonata depressa, new subspecies — Palau Islands:
Peleliu
Aaadonta pelewana, new species — Palau Islands: (exact locality
unknown)
Aaadonta irregularis (Semper, 1874) — Palau Islands: Peleliu
Aaadonta angaurana, new species — Palau Islands: Angaur
Aaadonta kinlochi, new species — Palau Islands: Angaur
GEOGRAPHIC KEYS TO THE GENERA
The following keys are based on the observed
range of variation for adult specimens. They often will
not work for juveniles or badly damaged shells. For
user convenience, only shell features are incorporated.
SYSTEMATIC REVIEW
125
Effective use of the keys to both genera and species
requires making standard measurements (fig. 5) and
calculating basic ratios. Where only one species in a
genus occurs in an island group, that species is listed
by name. Otherwise the generic key or discussion is
cross referenced.
Since the Caroline, Mariana, and main Fijian
Islands only have charopids, and no endodontids, keys
to these areas are omitted from Part I. The geographic
groupings, in order of presentation, are:
Austral Islands, except Rapa
Cook Islands
Ellice Islands
Hawaiian Islands
Lau Archipelago, Fiji
Mangareva, Gambier Islands
Marquesas Islands
Marshall Islands
Palau Islands
Rapa Island
Samoan Islands
Society Islands
Tonga
Tuamotu Islands, including Henderson
AUSTRAL ISLANDS, EXCEPT RAPA
1. Shell minute, diameter less than 1.8 mm.; at most 1 deeply
recessed parietal barrier, usually no barriers visible 2
Shell small to large, diameter 1.8-5.3 mm.; usually many
barriers, if only 1 parietal, then diameter over 4.2 mm 3
2. Apical sculpture of radial ribs; umbilicus very widely open;
body whorl deflected; diameter over 1.2 mm.
Discocharopa (see Part II)
Apical sculpture of spiral cords; umbilicus narrower; body whorl
not deflected; diameter less than 1.1 mm.
Punctum (see Part II)
3. Periphery angulated or keeled 4
Periphery rounded 5
4. Secondary spiral grooves visible at 80 X; or shell diameter over
3.5 mm Australdonta (p. 289)
No secondary spiral grooves visible at 80 X; diameter less than
3.2mm Mautodontha ceuthma (p. 158)
5. Secondary spiral grooving visible at 80 X; whorl count average
over 5'/2 Australdonta degagei (Garrett) (p. 298)
No secondary spiral grooving visible at 80 x ; whorl count
generally averages less than 5Vi Minidonta (p. 126)
COOK ISLANDS
1. Apical sculpture of spiral cords; no apertural barriers.
Charopidae (see Part II)
Apical sculpture of radial ribs; at least 1 apertural barrier 2
2. Umbilicus secondarily narrowed to form a brood chamber in
adults Libera (p. 390)
Umbilicus not secondarily narrowed to form a brood chamber in
adults 3
3. Apertural barriers numerous, expanded portion of palatals with
large points or hooks (figs. 192d, e).
Thaumatodon multilamellata (Garrett) (p. 448)
Apertural barriers numerous or reduced, with at most minute
serrations above 4
4. Shell diameter less than 2.4 mm.; sculpture very fine and
crowded; umbilicus open.
Minidonta rotellina (Pease) (p. 139)
Shell diameter more than 2.7 mm.; sculpture only very fine and
crowded if umbilicus closed Mautodontha (p. 151)
ELLICE ISLANDS
1. Apical sculpture of spiral cords Charopidae (see Part II)
Apical sculpture of radial ribs.
Thaumatodon decemplicata (Mousson) (p. 451)
HAWAIIAN ISLANDS
1. Periphery of shell sharply carinated; apertural barriers usually
large and prominent; sculpture often greatly reduced.
Endodonta (p. 371)
Periphery of shell rounded or bikeeled; apertural barriers large
in small (under 3 mm.) species, often reduced or absent in
larger; sculpture usually prominent 2
2. Parietal wall with 1-2 barriers or ridges, often with palatal
barriers; sculpture usually prominent.
Cookeconcha (p. 207)
Parietal wall with many threadlike traces, no palatal barriers;
sculpture moderately to greatly reduced.
Nesophila (p. 365)
LAU ARCHIPELAGO, FIJI
1. Apical sculpture of spiral cords Charopidae (see Part II)
Apical sculpture of radial ribs 2
2. Several apertural barriers; shell more than 2.5 mm 3
One or no apertural barriers, shell less than 2 mm.
Discocharopa (see Part II)
3. Umbilicus very widely open, D/U ratio 2.5-3.1; shell macroscop-
ically smooth Priceconcha tuvuthaensis (p. 465)
4. Shell with single keel; ribs few and protruded into "winglike"
extensions (fig. 198) Zyzzyxdonta alata (p. 466)
Shell with rounded periphery or bikeeled; shell sculpture not as
above Thaumatodon (p. 448)
MANGAREVA, GAMBIER ISLANDS
1. Umbilicus of adults secondarily narrowed to form a brood
chamber; diameter generally over 5 mm.
Gambiodonta (p. 434)
Umbilicus of adults not secondarily narrowed to form a brood
chamber; adult diameter generally less than 5 mm 2
2. Umbilicus widely open, contained less than 2.5 times in the
diameter; only 1 parietal and no palatal barriers.
Rikitea (p. 342)
Umbilicus narrowly open to nearly closed, often decoiling
irregularly; several parietal and palatal barriers.
Minidonta or Anceyodonta (see table LXVIII and
accompanying discussion)
MARQUESAS ISLANDS
1. Umbilicus very widely open, saucer-shaped, contained 1.6-2.2
times in the diameter Planudonta (p. 337)
Umbilicus much narrower, contained usually much more than
2.6 times in the diameter Taipidon (p. 317)
MARSHALL ISLANDS
1. Apical sculpture of spiral cords Charopidae (see Part II)
Apical sculpture of radial ribs 2
2. Parietal barriers 2 Cookeconcha subpaciftcus (Ladd) (p. 211)
Parietal barriers 3 Minidonta inexpectans (Ladd) (p. 132)
PALAU ISLANDS
1. Shell with prominent postnuclear radial ribs and much finer
microradials Charopidae (see Part II)
Shell without major radial ribs on postnuclear whorls, only fine
and very crowded microradials (figs. 203-208).
Aaadonta (p. 473)
126
SOLEM: ENDODONTOID LAND SNAILS
RAPA ISLAND
1. Umbilicus barely perforate or closed 2
Umbilicus normally to widely open 5
2. Shell periphery distinctly angulated or protruded.
Orangia (p. 276)
Shell periphery evenly rounded 3
3. Columellar barrier reaching lip edge, only 2 parietals.
Orangia cookei tautautuensis (p. 286)
Columellar barrier displaced onto basal lip, noticeably recessed,
or if reaching lip edge there are 3 parietal barriers 4
4. Columellar barrier parallel to plane of coiling, reaching nearly
to lip edge; apex flat, spire strongly elevated.
Opanara perahuensis (p. 253)
Columellar barrier deflected onto basal lip, or greatly reduced
and recessed; spire and apex strongly elevated.
Ruatara (p. 265)
5. Periphery nearly right angled; ribbing absent from body whorl
and shell base Kondoconcha (p. 368)
Periphery evenly rounded; ribbing present on body whorl and
shell base 6
6. Shell diameter less than 2.75 mm. and shell height less than 1.5
mm Rhysoconcha (p. 255)
Shell diameter more than 2.75 mm., or if less than 2.75 mm.,
then shell height more than 1.9 mm Opanara (p. 227)
SAMOAN ISLANDS
1. Apical sculpture of spiral cords Charopidae (see Part II)
Apical sculpture of radial ribs 2
2. No apertural barriers present; color white.
Discocharopa (see Part II)
Prominent apertural barriers present; shell variegated in color.
3
3. Shell diameter less than 2 mm.; apertural barriers minutely
serrated on expanded portion.
Minidonta manuaensis (p. 130)
Shell diameter over 3 mm.; apertural barriers "beaded" on
expanded portion (fig. 208e).
Thaumatodon hystricelloides (Mousson)
SOCIETY ISLANDS
1. Apical sculpture of strong spiral cords; aperture totally without
barriers; shell sculpture prominent.
Charopidae and Punctidae (see Part II)
Apical sculpture of radial ribs; aperture normally with at least 1
parietal barrier; if without parietal barrier then sculpture
absent and shell diameter over 7 mm 2
2. Shell diameter less than 2 mm.; only 1 parietal barrier.
Discocharopa (see Part II)
Shell diameter over 2.25 mm.; normally several apertural
barriers, or shell size over 3 mm 3
3. Umbilicus secondarily narrowed in adults to form a brood
chamber Libera (p. 390)
Umbilicus not secondarily narrowed in adults to form a brood
chamber 4
4. Shell sculpture greatly reduced; D/U ratio 1.7-3.0; whorls
averaging 6 or more Nesodiscus (p. 351)
Shell sculpture prominent; D/U ratio usually much more than
2.8; whorls averaging 5-5'/2, except in M. boraborensis, M.
consobrina, and M. maupiensis Mautodontha (p. 151)
TONGA
1. Shell aperture without barriers Charopidae (see Part II)
Shell aperture with barriers 2
2. Apical sculpture primarily of spiral cords.
Charopidae (see Part II)
Apical sculpture primarily of radial ribs.
Thaumatodon (p. 448)
TUAMOTU ISLANDS
1. Shell diameter of adults less than 2.6 mm.
Minidonta hendersoni (p. 134)
Shell diameter of adults over 2.9 mm 2
2. Whorl count less than 6'/2 3
Whorl count of adults more than 7 Jfleokyphus (p. 224)
3. Umbilicus cup-shaped, not secondarily narrowed; diameter at 5
whorls less than 4.00 mm
Mautodontha daedalea (Gould) (p. 157)
Umbilicus secondarily narrowed to form a brood chamber;
diameter at 5 whorls more than 5.5 mm.
Pseudolibera UUianae (p. 383)
Genus Minidonta, new genus
Generally small to minute (except M. extraria, M. anatonuana,
and M. planulata) Endodontidae in which the umbilicus is internally
constricted or U-shaped with the last whorl decoiling rapidly (except
M. gravacosta and M. hendersoni). Apical and microsculpture
typical of family (except secondary spiral cording present in M.
haplaenopla), radial sculpture of prominent, normally spaced ribs
(very fine and crowded only in M. rotellina; widely spaced only in
M. taravensis and M. extraria). Apex and spire normally elevated
(M. micro and M. hendersoni relatively high; M. gravacosta and M.
planulata rather depressed), body whorl not descending more
rapidly. Whorls usually 43/i-55/8, normally coiled, reduced in number
for minute species (M. micro, M. manuaensis, M. inexpectans).
Parietal barriers basically 3, 2 in M. sulcata and M. gravacosta, 4 in
M. taravensis, rarely with accessory traces, highly specialized in M.
extraria. Columellar barrier prominent to absent. Palatal barriers
simple blades, 2-5, usually 4 in number, many species with accessory
traces, bulbous only in M. micro and M. extraria. All barriers
reduced in size in several species (M. planulata, M. haplaenopla, M.
simulata, M. anatonuana). Anatomy almost unknown. Penial
retractor originating from diaphragm, remaining genitalia as in
Endodonta.
Type species.— Minidonta hendersoni, new species.
The unusual coiling pattern of the umbilicus (figs.
62, 63b, 69c) is the main differentiating character of
this otherwise diverse group. Generalized in sculpture
and form, specializations in tooth structure closely
approach the patterns of Mautodontha, Anceyodonta,
and Australdonta. The species included in Minidonta
show distinct sculptural, size, and umbilical differences
from the species of Anceyodonta and Australdonta,
while the approach to Mautodontha is closer in several
respects.
Departures from the umbilical pattern are few
and can be attributed to secondary shell modifications.
In M. sulcata (fig. 68e, f) the marked columellar
sulcus visually obscures the coiling pattern, which,
while not as extreme as in M. planulata, is typical. In
M. gravacosta and M. extraria, the relatively de-
pressed apex and low H/D ratio probably correlate
with the near regular decoiling of the umbilicus.
Similarly, M. hendersoni with its very high spire and
wide umbilicus shows only a slight increment in last
whorl decoiling. The only species whose relatively
regularly decoiling umbilicus cannot be explained as a
secondary modification is M. haplaenopla (fig. 69f). In
that species the size, shape, and dentition are so
similar to other Minidonta that I have no hesitation in
so classifying M. haplaenopla.
SYSTEMATIC REVIEW
127
Unlike the distinctive microsculpture of Anceyo-
donta or Australdonta, all species of Minidonta have
the primitive endodontid pattern of fine radials crossed
by distinctly finer and more crowded spirals. Only in
M. haplaenopla is there a weak secondary sculpture of
spiral cords developed. Similarly, most species have a
simple radial sculpture of prominent, rather closely set
major radials. M. rotellina is unique in its very fine
and crowded radial sculpture and M. inexpectans also
has quite crowded sculpture. In contrast, the sculpture
of M. taravensis is quite widely spaced, much as in
Anceyodonta. The low rib counts of M. micraconica
and M. micro, however, are a function of small size
rather than alteration in rib size or spacing.
Umbilical width is rather variable (table LXIII),
with two species, M. rotellina and M. planulata,
having very narrow umbilici, and four species, M.
taunensis, M. hendersoni, M. inexpectans, and M.
gravacosta, having widely open umbilici. In M.
hendersoni and M. gravacosta the increase in umbilic-
al width seems to have changed the coiling pattern,
but the other species do not seem to have been
affected.
Three species, M. planulata, M. anatonuana, and
M. extraria are relatively large (2.90-3.26 mm. in mean
diameter), while M. inexpectans, M. manuaensis, and
M. micra are minute (mean diameter 1.68-1.83 mm.).
Of the large species, M. planulata and M. extraria are
enlarged by depression of the apex and resulting
loosening of coiling; M. anatonuana by a slight
increase in whorl count. Size reduction in the small
species is an effect of decrease in whorl count to 4 1/16
or 4'/2, without any change in whorl size. In many New
Zealand charopids, such as Ptychodon, size reduction
results from narrowing of the later whorls, with a
bulbous nucleus indicating relationship to larger
species. No such change is found in any of the Pacific
basin Endodontidae.
Patterns of barrier change are more complex
(table LXIII). Of the Austral Island species, M.
anatonuana has typical dentition with elongated,
flatly lamellar palatal barriers (fig. 68b). M. sulcata
(fig. 68e) has the parietals reduced to 2 and the
palatals reduced in height and length. This fore-
shadows the great size reduction seen in the apertural
barriers of M. planulata and M. haplaenopla (fig. 69).
A different pattern of specialization is seen in the
very small M. micraconica and M. gravacosta. The
upper parietal is bifid (fig. 65d-e), there is a very large
columellar barrier, and 5 prominent palatals plus one
or two accessory traces. The palatals are shorter and
less flatly lamellar than in M. anatonuana or the
Mangarevan species, more closely resembling the form
seen in the more heavily toothed species of Mau-
todontha, such as Mautodontha zimmermani (fig.
74b).
The Mangarevan species show even wider diver-
gence in barrier form. Minidonta micra (fig. 63a) has
very large, rather bulbous barriers, quite similar in
form to those of M. micraconica (fig. 65b), only
without a bifid upper parietal and having the
columellar barrier greatly reduced in size. Minidonta
simulata (fig. 70a) and M. taravensis (fig. 71c) have
rather large and elongated barriers, similar to those of
M. anatonuana (fig. 68b) and approach (simulata) or
are essentially identical to (taravensis) the tooth form
seen in Anceyodonta. M. taravensis has a 4th parietal
and the columellar barrier greatly modified, but is
closely related to M. simulata. In M. taunensis (fig.
70e) the barriers are simple and very elongated, much
more so than in M. simulata. Their form is that of the
elongated Anceyodonta and Mautodontha. Finally,
Minidonta extraria has the unique splitting of the
parietals (fig. 7 If) and short, high, rather bulbous
palatals. These barriers are totally unlike those in
other species of Minidonta.
In the Henderson Island M. hendersoni (fig. 63c),
the barriers are basically identical to those of the
Mangarevan M. micra, differing primarily in the heavy
callus on the palatal wall that reduces the size of the
palatal barriers considerably. The Samoan M. manu-
aensis (fig. 62b) and Bikini Atoll fossil M. inexpectans
(fig. 62d) have the barriers slightly reduced in size
from those found in micra and hendersoni and lack
the accessory traces. They are, however, essentially
identical in barrier structure.
Finally, the Aitutaki Minidonta rotellina (fig. 62e)
has very elongated barriers that are not directly
similar to any other species of Minidonta, but show
some strong similarities to those of Mautodontha
imperforata (fig. 76e).
On the basis of the observed variation, I recognize
five species groups within Minidonta, based on
barriers, sculpture, size, and shape. They are:
Group of Minidonta micro— shell minute to very
small; sculpture prominent; spire normally
to strongly elevated; umbilicus usually
widely open; 3 parietals, 3 or 4 palatals,
with barriers not particularly elongated—
M. micra, new species
M. hendersoni, new species
M. inexpectans (Ladd, 1958)
M. manuaensis, new species
Group of Minidonta micraconica— shell very small;
sculpture quite prominent; spire normally
elevated or depressed; umbilicus normal to
widely oepn; parietals 2 or 3, upper
bifid, columellar large, 5 palatals, barriers short and
prominent—
M. micraconica, new species
M. gravacosta, new species
Group of Minidonta rotellina— shell very small; sculpture
very fine; spire normally elevated; umbilicus very
narrow; 3 parietals, very small columellar ridge;
palatals 2, barriers elongated—
M. rotellina (Pease, 1870)
Group of Minidonta anatonuana— shell of average size to
very large; sculpture normal; spire depressed to
moderately elevated; umbilicus normal to narrow;
parietals 3 or 4, all barriers normal to reduced, not
particularly elongated—
128
SOLEM: ENDODONTOID LAND SNAILS
M. anatonuana, new species
M. sulcata, new species
M. haplaenopla, new species
M. planulata, new species
Group of Minidonta simulata— shell of normal to rather
large size; sculpture rather widely spaced; spire flat
to normally elevated; umbilicus wide to narrow; parietals
3 or 4, columellar usually present, palatals 4, with or
without accessory traces, all barriers elongated (except
extraria)—
M. taunensis, new species
M. taravensis, new species
M. simulata, new species
M. extraria, new species
The above groups show different affinities. The
micraconica complex is an obvious specialization of
the micro, group, which is the basic structural type
within Minidonta. The anatonuana group parallels
Australdonta in its general reduction in tooth size,
large size, and rather depressed shape, but obviously
differs in its umbilical coiling, microsculpture, absence
of a supraperipheral sulcus, and absence of peripheral
angulation. M. rotellina is without obvious relation-
ships and stands as an isolated species. Finally, the
simulata complex has more the shape of Mautodontha,
but the sculpture, color, and dentition grade into
Anceyodonta.
Despite the varying differences cited above, Mini-
donta presents a basic set of similarities that far
outweighs individual species group trends. The large,
regularly decoiling umbilicus, rather flat spire, rapidly
descending body whorl, and generally much larger size
of Mautodontha contrast to the constricted umbilicus,
elevated spire, normal body whorl, and small size of
Minidonta. Similarly, the large size, angled periphery
with supraperipheral sulcus, microspiral grooving, and
generally flat spire separate Australdonta. Species of
the Mangarevan Anceyodonta often have strong spiral
secondary sculpture, a generally minute umbilicus,
very high spire, and complicated barriers; Anceyodonta
is easily derivable from the simulata group of
Minidonta, but unquestionably distinct from the other
species groups.
Geographically, Minidonta has the widest dis-
tribution in the Endodontidae. Living (or recently
extinct) species are found from Samoa to Henderson
Island, a range of perhaps 2,700 miles over 41° of
longitude. The fossil record from Bikini, of either
Pleistocene or Pliocene age, nearly doubles the range.
Current centers of speciation lie on Raivavae, Austral
Islands and Mangareva, Gambier Islands, each with
five species. Single living species are known from the
Manua group in American Samoa (Minidonta manu-
aensis), Rurutu, Austral Islands (M. haplaenopla),
Aitutaki, Cook Islands (M. rotellina), and Henderson
Island (M. hendersoni). There is also the single fossil
record from Bikini Atoll, Marshall Islands (M. in-
expectans).
Species groups show simple distribution patterns,
with the simulata group confined to Mangareva; the
anatonuana group present on Raivavae and Rurutu;
rotellina, an isolated species taxonomically and geo-
graphically, found only on Aitutaki; the micraconica
group restricted to Raivavae; and the micro complex
widely dispersed with species on Henderson, Man-
gareva, Raivavae, Manua Group and Bikini as a fossil.
The most generalized stock thus has the widest
distribution, including both the easternmost (Hen-
derson) and westernmost (Manua) records.
The difficulties of dating the Bikini fossil, M.
inexpectans, were discussed by Ladd (1958, pp. 188-
189). As a Pleistocene or, less probably, a Pliocene
species, this would seemingly indicate a young age for
the distribution pattern. More critical examination
suggests instead that this is a relict pattern. The
existence of the micra group on the fringes of
distribution— Henderson Island, Manua Group, and
Bikini (during an elevated period of that atoll) — with
a single species on a center of speciation, Mangareva,
and a derived group, the micraconica pair, on the
other center of speciation, Raivavae, is only part of the
pattern. With the exception of Minidonta rotellina
from Aitutaki, Cook Islands and Mautodontha
ceuthma from Raivavae, both species standing quite
isolated in their affinities and of uncertain clas-
sification, Mautodontha and Minidonta show a clear
replacement pattern, with Mautodontha occupying the
Cook, Society, and endodontid inhabitable Tuamotus,
while Minidonta has a semi-circular fringing pattern of
Manua Group Austral Islands, Mangareva and Hen-
derson.
If Minidonta was limited to this fringing pattern
and showed indications of being derived from
Mautodontha by size reduction, then interpretation as
a recent, secondary dispersal from a Society-Cook
center of evolution would make sense. Size reduction
in charopids apparently normally is accomplished by
narrowing of whorls after the nucleus, with a huge
nucleus remaining. There is no indication of this in
Minidonta and fewer changes would be required in
dentition and shell structures to derive Mautodontha
from Minidonta than the reverse. Coupled with the
presence of Minidonta inexpectans on Bikini, it makes
more sense to view the recorded forms of Minidonta as
stable relicts of a former, nearly continuous dis-
tribution through Polynesia, replaced in most of
Samoa by Thaumatodon and in the Society-Cook-
Tuamotu-Rapa-Marquesan area by more specialized
genera, each with quite limited distribution in
comparison. The presence of M. hendersoni on a raised
makatea island provides evidence tending to confirm
the hypothesis of Ladd (1958, p. 196) that M.
inexpectans was "...probably lodged in crevices in
elevated lagoonal limestone while they were above the
sea undergoing subaerial erosion."
Only one species has been dissected. M. hender-
soni differed significantly from Endodonta only in
having the penial retractor originate from the dia-
phragm.
o
i
D
"Q
49
I
Q
^
X
S
u
ol
s
3
p o c
5 v a
3 D, x
Z co PU
u
rt
z
•* C0|
CM rHl rH
^ 1
CM)
1 1 CM
1 I I
1
rH
CO
i
CO
CO
0| rH H-
rH O O
•«•
CO
CO
,— I
T^I
4 4 m
+ + +
VO CM ^*
I
4
4
^
rH
•*
•H|
rH
rH
rH r rH
rH rH O
rH
0
0
rH
rH
I
rH
ol
O
rH rH
t 1 rH
rH
CO
Ol
CO
CO
Ol 0 rH+
CM CO CO
01
CO
CO
^t
CO
CO
+ + CO
CO CO
CO
rH
CD
O
O
•*'
CO IO CO
00 CO C-
U3 ^ CO
CM rH CO
Ol CM t~
^J1 00 C~~
O
0
in
m
c-
m'
CO
C-
CO
CO
CM
CO
CD
rH
CO
CD
rH
10'
I
1 I 1
1 1 1
i
i
1
1
1
1
Oi
E-
CD
en
rH OS CM
CO O ^
CO Ol O
IO CM Ol
0
0
CD
CM
c~
CO
IO
o
0
••*
s
IO
CM
V
co'
CO* CO* ^<*
co" 10" •*£
•*'
••*'
CO
CO
in
CO*
in
CO
oo
O3 t- CO
Ol O C-
0
CO
CM
CD
t-H
in
CO
CN
en
Ol CO IO
Ol rH CO
m
o
rH
CO
rH
CO
CO
10
co'
^ CO IO
CO C- XO
•*'
in
f"
co'
CO
-*'
in'
--N OO
0?
s~*
CO
0?
0?
^
CO X-N
in
^^
IO
in
IO
CM IO
in
00
IO
•^ \ 1
CM
i
00
"^s.
IO
in
rH
1 rH CO
>^
^^
00
CO
4
i
iH
rH
CO
oo
^J1
^J*
***v IO U3
f~^ S~^.
in
m
IO
^^
CO
i
rH i
IO CD CO
i
10
1
rH
CM Tf
1 1 t
in
1
IO
crT
•*
^f IO *O
i
•5*
co'
in
^
in
c* T"H co
"co ^ ^
oo
CO
CO
rH
of
00
CM"
rH
rH ^ t-
•^ CO rH
rH
rH
J,
CO
rH
rH
rH
X
^
IO IO IO
IO
in
IO
IO
m
IO
IO
O
Oi
10
t-
IO
c- 10 IT-
CD co en
CO CO IO
10 rH CO
CM rH CO
iO CD CO
0
0
CD
CO
o
CO
c-
rH
»O
Ol
CM
10
CO
IO
in
00
IO
CD
i
IO
0
O
o o o
0* 0* 0
O
o
O
o
o'
O
0
1
1
1 t I
1 1 I
1
i
1
1
CO
en
CO IO 0
^M Ol O
^
CO
Tt*
to
CO
CO
o
CO
in
CO C- CO
CM CO O
o
CO
CM
•*
rH
o
10
IO IO IO
T* IO IO
in
in
^
IO
in
in
in
o
o
o o o
o o o
o
o
0*
0*
0
o*
o
CM
c—
CD
IO rH IO
CM CM f-
CD CO IT-
CO t- C—
t-
00
CO
CO
IO
01
5
rH
in
CM
CD
Ol
rH
iO
in
CO CO IO
T* 10 U3
in
in
•^
in
in
in
IO
0
0
O O O
C3 O CD
0
0
o
o
o
o
co,^
0
CO
CO
1
00
rH
Ol IO IO
co -^ o
rH CM CM
III
CT> Ol iO
0 rH CM
CM* CM* CO*
1 1 1
CM
CO
CM"
i
rH
O
CO*
1
rH
CO*
CM
CO
CM'
CO
CD
CM'
CO
CO
CM*
1
CO
o
co'
1
Oi
Ol
C— IO U3
03 CO CO
in
CO
CO
Oi
CO
CO
CO
10
00
CD CO Oi
IT- 00 C-
01
CM
Ol
rH
•<c
•*
t-
J-H
rH
rH rH rH
r-C rH CM
01
01
CM
01
CM
CM
01
CO
CD
«
00
CO CO O
C- rH O
C- t- CM
O3 Ol O
oo
01
0<
in
CO
CM
in
01
00
IO
CM
C-
0
en
rH
rH
rH CM* CM*
rH rH CO
CM
Ol
CO
CM
CM
01
CM
00
o
in
o
Ol Ol CO
rH IO CM
CO CO -^
O CO O
cn
01
00
oT"
CO
CO
CM
en"
CO
c-
rH
in
rH
rH
rH rH rH
rH rH CM
iH
rH
rH
rH
rH
rH
rH
I
III
1 1 1
1
1
1
1
1
Oi
CO
01
0
CD CO CO
Ol i-l OS
CO CM CO
OO O ^
01
CO
Ol
Ol
CO
rH
CO
CO
00
CO
^
o
rH
O rH O
O rH rH
rH
rH
rH
rH
rH
rH
rH
co'
OS
\
Ol ** IO
0 CO r-t
CM' co' ^
03 rH C-
en
CO
CO
CO
CO
CO
rH
01
IO
$
0
rH
rH rH rH
O rH rH
rH
rH
rH
rH
rH
rH
rH
f — .,
O
CO
0
r-t
1
CD
CO
IO
rH
Ol IO O
CO Ol C-
I I I
CM IO IO
VO C- CD
s § f
en « co
10 pi co
C-J
rH
t
in
o
rH
S1
CM
rH
s
6?
Ol
t
CO
CO
rH
rH
C?
C-
1
s
if
i
rH
U?
t-
I
c-
co
co"
t
OO Ol CO
0 CM* IT-*
CD CO CO
CM' P 10
rH O ^*
C~- CO
U3
CM"
rH
rH
CD
01
0
rH
CO
if
o
CO*
CO
U3
oo'
c-
CO^
rH
IT-
en
CD
CO CO ^t<
rH IO CO
•*
c*
t-
CM
CM
01
CO
CM 0
•^ CM CO
tr-
CO
CM IO
manuaensls
inexpectans
micra
hendersonl
mlcraconica
S ^ ^ 5
§ 12 §
a ^ 2
MJ S rt
sulcata
haplaenopla
planulata
taunensls
taravensis
simulata
extrarla
&
" a
M t— I
nJ X)
•g u
o
o o
•
C ^-i
O nJ
-
.
;b u] <1
^ oi co' •
129
130
SOLEM: ENDODONTOID LAND SNAILS
KEY TO THE GENUS Minidonta
1. Upper parietal barrier simple; palatal barriers 4 or less 3
Upper parietal barrier bifid (fig. 65d, e); palatal barriers 5 2
2. Parietal barriers 2, H/D ratio less than 0.540.
Minidonta gravacosta, new species
Parietal barriers 3, H/D ratio more than 0.540.
Minidonta micraconica, new species
3. Umbilical wall rounded, normally 3 parietal barriers 4
Umbilical wall with prominent sulcus (fig. 68f), 2 parietal
barriers Minidonta sulcata, new species
4. Body whorl with less than 150 radial ribs, 3 or 4 palatal barriers.
5
Body whorl with more than 200 radial ribs, only 2 major palatal
barriers Minidonta rotellina (Pease, 1870)
5. Mean adult size less than 2.0 mm 6
Mean adult size more than 2.0 mm 8
6. Palatals 3, no accessory traces 7
Palatals 4, normally with accessory traces.
Minidonta micro, new species
7. More than 125 ribs on body whorl; mean D/U ratio about 4.00.
Minidonta inexpectans (Ladd, 1958)
Less than 125 ribs on body whorl; mean D/U ratio about 5.25.
Minidonta manuaensis, new species
8. Mean D/U ratio less than 4.00 10
Mean D/U ratio much more than 4.00 9
9. H/D ratio less than 0.550; no accessory parietal traces;
Mangareva Minidonta taunensis, new species
H/D ratio more than 0.550; usually an accessory parietal trace;
Henderson Island Minidonta hendersoni, new species
10. Parietal barriers simple 11
Each parietal barrier split into several traces (fig. 71f).
Minidonta extraria, new species
11. Parietal barriers 3 12
Parietal barriers 4 Minidonta taravensis, new species
12. Mean D/U ratio about 5.00 13
Mean D/U ratio more than 5.50 14
13. Mean body whorl rib count less than 90; 4 palatals.
Minidonta simulata, new species
Mean body whorl rib count more than 100; usually 3 palatals.
Minidonta haplaenopla, new species
14. Palatal barriers 4; mean H/D ratio about 0.575.
Minidonta anatonuana, new species
Palatal barriers 3; mean H/D ratio about 0.500.
Minidonta planulata, new species
GROUP OF Minidonta micra
Minidonta manuaensis, new species. Figure 62
a-c.
Diagnosis.-She\\ minute, diameter 1.59-1.83 mm. (mean 1.68
mm.), with 4-4V4 normally coiled whorls. Apex and spire moderately
and evenly elevated, last whorl descending more rapidly, H/D ratio
0.563-0.590 (mean 0.572). Umbilicus narrow, U-shaped, last whorl
dec-oiling more rapidly, contained 4.79-6.13 times (mean 5.28) in the
diameter. Postnuclear whorls with narrow, rounded, almost verti-
cally sinuated radial ribs, 86-108 (mean 94.3) on the body whorl,
whose interstices are 2-4 times their width. Microsculpture of very
fine radial riblets, four to eight between each pair of major ribs,
crossed by distinctly finer and more crowded spiral riblets. Sutures
impressed, whorls almost equally rounded on outer margins.
Aperture subcircular, inclined about 5° from shell axis. Parietal
barriers 3, short, extending somewhat more than one-eighth whorl:
upper high and bladelike for entire length, expanded and serrated for
posterior two-thirds, with sharp anterior descension; 2nd equal in
height posteriorly, less expanded above, with gradual descension over
anterior half; 3rd slightly reduced in height posteriorly, anterior third
a threadlike trace. Columellar barrier a low, broadly rounded,
recessed ridge, lying parallel to plain of coiling. Palatal barriers 3,
rather prominent blades, extending a little more than one-eighth
whorl: lower somewhat recessed greatly reduced in height, with very
gradual anterior descension; 2nd much higher, bladelike, with
sharper anterior descension; 3rd equal in height to 2nd, with more
gradual anterior descension, nearly reaching lip margin. Some
specimens have a barely detectable bulge where 4th palatal normally
lies.
The Bikini fossil Minidonta inexpectans differs in
having more crowded radial ribbing (145 on the body
whorl), a wider umbilicus (D/U ratio 3.96-4.00), the
body whorl slightly compressed laterally, and the
lower palatal barrier more reduced. Minidonta
taunensis from Mangareva has a 4th palatal barrier
above the periphery, the lower palatal not reduced in
size, is larger (diameter 2.17-2.30 mm.), has a wider
umbilicus (D/U ratio 3.05-3.67) and is less elevated
(H/D ratio 0.525-0.529). Other species differ obviously
in size, sculpture, or form and cannot be confused.
Description.— Shell minute, with 3% normally coiled whorls
before being broken. Apex and spire evenly elevated, last whorl
descending a little more rapidly, H/D ratio 0.574. Embryonic whorls
l5/s, sculpture of radial riblets, whose interstices are 3-4 times their
width, and much finer, slightly more crowded spiral riblets.
Postnuclear whorls with narrow, rounded, vertically sinuated radial
ribs, 80 on the body whorl, whose interstices are 3-5 times their
width. Microsculpture of very fine radial riblets, three to six between
each pair of major ribs, crossed by much finer and more crowded
spiral riblets. Sutures deep, whorls evenly rounded on outer margin.
Color light reddish-yellow without trace of darker markings.
Umbilicus narrow, U-shaped, barely decoiling, contained 6.27 times
in the diameter. Aperture subcircular, inclined less than 5° from shell
axis. Parietal barriers 3, extending less than three-sixteenths of a
whorl: upper a high lamella for entire length, posteriorly expanded
and serrated, much of anterior end partly broken; 2nd equal in
height posteriorly, with gradual descension for anterior half; 3rd
reduced in height posteriorly, anterior quarter threadlike. Columellar
barrier recessed, a broad, low, rounded ridge lying parallel to plane of
coiling. Palatal barriers 3, prominent, extending about one-eighth
whorl: 1st reduced in height, with gradual anterior descension; 2nd
much higher less recessed, with sharper anterior descension,
expanded above; 3rd equal in height to 2nd, with more gradual
anterior descension. Height of holotype 0.89 mm., diameter 1.55 mm.
Holotype.— Samoa: Manua Islands, Ta'u, Utu-
manu'a ridge at 350 ft. elevation. Collected by Wray
Harris on June 28, 1937. Bernice P. Bishop Museum
number 187207.
Range.— Olosega and Ta'u, Manua Islands, Samoa.
Paratypes.— Same as list of material.
Material.— Manua Islands: TA'U, Utumanu'a
ridge at 350 ft. elevation (1 specimen, BPBM 187207);
OLOSEGA, Olosega village, pastor's grounds, 600 ft.
inland at 12 ft. elevation (8 specimens, BPBM 186758,
BPBM 186774, BPBM 188720).
Remarks.— Unfortunately, the type specimen was
damaged during cleaning prior to illustration, and the
dotted lines in Figure 62a, b indicate the original
contours. Since the single Ta'u example was better
preserved than any of the Olosega shells, it has been
selected as holotype.
Only dead specimens from sweepings at the base
of a kapok plant or from a pocket of leaf mould in
coralline rock are known. Possibly the species still
ef
FIG 62. a-c, Minidonta manuaensis, new species. Utumanu'a ridge, Ta'u, Manu'a Islands, American Samoa. Holotype. BPBM 187207; d,
aperture of Minidonta inexpectans (Ladd). Holotype. USNM 562088; e-f, Minidonta rotellina (Pease). Aitutaki, Cook Islands. Lectotype.
BPBM 2312. Scale lines equal 1 mm. (MM).
131
132
SOLEM: ENDODONTOID LAND SNAILS
exists on the upper peaks of Ta'u or Olosega, although
it is almost certainly absent from lowland areas except
as fossils. Collections made at 1,300-1,500 ft. elevation
in 1975 failed in locating this species. Since M. hender-
soni, from the opposite geographic limit, is the only
other Minidonta that has been dissected, study of M.
manuaensis is especially desirable.
Minidonta inexpectans (Ladd, 1958). Figure 62d.
Prvcnorfon inexpectans Ladd, 1958, Jour. Paleontol., 32, (1), pp.
188-189, pi. 30, figs. 1-6 - Drill hole 2A at 447-453 foot depth,
Bikini Atoll, Marshall Islands (Pleistocene- Pliocene).
Diagnosis.— Shell very small, diameter 1.82-1.84 mm. (mean 1.83
mm.), with 4'4 tightly coiled whorls. Apex and spire moderately and
evenly elevated. H/D ratio 0.559-0.571 (mean 0.565). Umbilicus U-
shaped, last whorl decoiling more rapidly, contained 3.96-4.00 times
(mean 3.98) in the diameter. Postnuclear sculpture of fine, crowded,
slightly protractively sinuated radial ribs, about 145 on the body
whorl, whose interstices are l-l'/2 times their width. Aperture ovate,
compressed laterally, lip broken. Parietal barriers 3, upper
lamellate for entire length, lower 2 with anterior third threadlike, all
extending one-quarter whorl posteriorly. Columellar barrier a low
recessed ridge with anterior tip angling slightly downward. Palatal
barriers 3; lower a small trace, upper 2 prominent lamellar ridges.
The Samoan Minidonta manuaensis is nearly
identical, differing in having coarser ribbing (85-110 on
the body whorl), a smaller umbilicus (D/U ratio 4.79-
6.27) and the body whorl less laterally compressed; M.
taunensis from Mangareva has the anterior threadlike
portion of the lower parietals longer and finer; the
columellar barrier slanting down more sharply; the
lower palatal barrier large, middle two identical, and
an additional supraperipheral palatal. It also differs in
features of coiling, ribbing, and umbilicus.
Description.— Shell very small, with very slightly less than 4',4
tightly coiled whorls. Apex and spire moderately and evenly
elevated, body whorl descending distinctly more rapidly, H/D ratio
0.559. Apical whorls 1%, partly eroded, with traces of widely spaced
radial ribs remaining on midportion. In umbilicus, apical sculpture
seen as major radial ribs, with finer radials between and barely
visible spiral riblets. Remaining whorls with fine, crowded, very
slightly protractively sinuated radial ribs, 145 on the body whorl,
whose interstices are l-l'/2 times their width. Microsculpture
occasionally visible as network of very fine radials and spirals.
Sutures deep, whorls strongly rounded above, compressed laterally
with evenly rounded outer and basal margin, umbilical wall strongly
rounded. Ground color leached from shell except for narrow to broad
radial reddish-yellow markings reaching from suture to periphery,
absent on base of shell. Umbilicus open, U-shaped, last whorl
decoiling noticeably more rapidly, contained 3.96 times in the
diameter, whorls strongly rounded inside. Aperture lunate, strongly
rounded above and on umbilical wall, compressed laterally with
evenly rounded outer and basal margin, inclined less than 10° from
shell axis. Parietal barriers 3, high and bladelike, extending one-
quarter whorl posteriorly: upper thin, high and lamellate for entire
length, with very sharp anterior descension, upper edge slightly
expanded; middle parietal with anterior third a high threadlike ridge,
gradually descending in midportion from posterior elevated lamellar
part that is only two-thirds height of upper parietal; lower parietal
same shape as middle, anterior third very low and threadlike, both
lower parietals extending slightly anterior of upper. Columellar
barrier a low threadlike ridge slightly more elevated posteriorly and
extending beyond line of vision, parallel to plane of coiling, with its
tip angling very slightly down across posterior edge of columellar
callus, and ending well short of lip edge. Palatal barriers 3: lower a
very small, short, recessed, threadlike trace, basal in position,
stopping well short of lip edge; upper 2 moderately elevated
lamellate ridges, extending posteriorly three-sixteenths of a whorl,
gradually descending anteriorly almost to edge of lip callus; upper
palatal slightly subperipheral, pointing between upper and middle
parietal; 2nd palatal located midway between upper and lower
palatal teeth, pointing between middle and lower parietal. A faint
swelling occupies slightly supraperipheral position near lip edge. Lip
edge thickened with distinct callus, fading out near periphery,
strongest on columellar wall. Height of holotype 1.02 mm., diameter
1.84mm.
Holotype.— Marshall Islands: Bikini, drill hole 2A
at 447-453 ft. deep. USNM 562088.
Range.— Known only from the type collection.
Paratypes.-USNM 562089.
Remarks.— Cleaning of the holotype by sonic
vibrations revealed the presence of a columellar and
lower palatal denticle, features not detected during the
original study. In addition, there is a weak bulge
present in the upper palatal lip that can be interpreted
as a remnant of a 4th palatal tooth. Since other
features of the shell are well shown in the original
figures (Ladd, loc. cit.), only an apertural view (fig.
62d) has been presented in this study.
Classification in Minidonta is based on the
characteristically constricted umbilicus (Ladd, 1958,
pi. 30, fig. 4), absence of distinctive microsculpture,
form and number of the apertural barriers, and close
similarities to M. manuaensis. If inexpectans and
manuaensis were found on the same island or on
adjacent islands, they unquestionably would be consid-
ered of monophyletic origin. Their differences, dis-
cussed above in the "Diagnosis," are comparatively
minor when compared to the differences among other
Minidonta.
Dating of this species is uncertain. According to
Ladd (1958, pp. 188-189), the shells were with "...fauna
of shallow water and marine mollusks that is
definitely post-Miocene, probably Pliocene. The land
shells probably were brought in at a later date when
the marine limestone was above the sea undergoing
solution and recrystallization; the land shells may be
Pleistocene." The closeness to an existing species has
no bearing on its probable age, since many recent
molluscan species are known from Pleistocene and
Pliocene strata.
Minidonta micra, new species (Solem & Cooke).
Figure 63a-b.
Diagnosis.— Shell minute, diameter 1.67-1.89 mm. (mean 1.73
mm.), with 4'/i-43/4 normally coiled whorls. Apex and spire moderately
and evenly elevated, last whorl descending more rapidly, H/D ratio
0.563-0.667 (mean 0.625). Umbilicus constricted internally, last whorl
decoiling quite rapidly, contained 3.61-5.88 times (mean 4.99) in the
diameter. Postnuclear whorls with broad, prominent, protractively
sinuated radial ribs, 52-69 (mean 60.8) on the body whorl, whose
interstices are l'/2-3 times their width. Microsculpture a lattice of
extremely fine radial and spiral riblets. Sutures impressed, whorls
evenly rounded, except for. slight lateral compression below per-
iphery. Aperture ovate, inclined about 10° from shell axis. Parietal
barriers 3, extending one-quarter whorl, usually (70 per cent) with an
SYSTEMATIC REVIEW
133
FlG. 63. a-b, Minidonta micro, new species. Station 102, Aukena Islet, Mangareva, Gambier Islands. Holotype. BPBM 138757; c-d,
Minidonta hendersoni, new species. Station 254, Henderson Island, Tuamotus. Holotype. BPBM 149858. Scale lines equal 1 mm. Drawings by
YK reproduced through the courtesy of Bernice P. Bishop Museum.
inconspicuous accessory trace: upper a high ridge, grossly expanded
and serrated on posterior two-thirds, anterior quarter narrow, with
gradual descension; 2nd with posterior section slightly shorter than
1st, but otherwise identical, anterior third gradually descending; 3rd
greatly reduced in height posteriorly, much narrower above,
gradually descending over anterior half. Accessory trace, when
present, located above upper parietal, midway to parietal-palatal
margin. Columellar barrier a broad, low, serrated ridge, moderately
recessed, lying parallel to plane of coiling. Palatal barriers 4,
extending more than one-eighth whorl, with a variable number of
accessory traces: lower nearly reaching lip edge, high, expanded, and
serrated on posterior half, with sharp anterior descension; 2nd
slightly lower than 1st, lying opposite 2nd parietal, with more
gradual anterior descension; 3rd equal in height to 1st, longer, with
more gradual anterior descension; 4th supraperipheral, a low,
broadly rounded, moderately recessed ridge. Accessory traces
variable in number, present above 4th palatal (one or two) and
between various lower palatals or the columellar and lower palatal.
Columellar and palatal walls with heavy, broadly rounded callus
extending up to and including region of 4th palatal.
The minute size, presence of accessory palatal
traces, and high spire immediately separate M. micra
from the other Minidonta. Anceyodonta ganhutuensis
can be confused, but has a tiny umbilicus (mean D/U
ratio 15.8), a much higher spire (mean H/D ratio
0.789), and more whorls. Minidonta hendersoni is
almost identical in shape and barrier structure, but is
distinctly larger (mean diameter 2.16 mm.), has finer
sculpture, and a wider, less constricted (mean D/U
ratio 3.67) umbilicus.
Description.— Shell minute, with 4'/2 normally coiled whorls.
Apex and spire markedly elevated, last whorl descending a little
more rapidly, H/D ratio 0.596. Embryonic whorls m, with faint
traces of microradial and microspiral sculpture remaining in sutures.
Postnuclear whorls with broad, high, slightly protractively sinuated
radial ribs, 60 on the body whorl, whose interstices are 2-3 times their
width. Microsculpture a lattice of coequal, extremely fine radial
and spiral riblets. Sutures impressed, whorls evenly rounded,
somewhat compressed laterally below periphery. All color leached
from shell. Umbilicus strongly constricted internally, last whorl
dec-oiling quite rapidly, contained 4.96 times in the diameter.
Aperture ovate, slightly compressed laterally below periphery,
inclined about 5° from shell axis. Parietal barriers 3, extending a
134
SOLEM: ENDODONTOID LAND SNAILS
little more than one-quarter whorl; upper quite high, posterior two-
thirds grossly expanded and serrated, anterior quarter descending
gradually; 2nd slightly higher, posterior elevated portion a little
shorter; 3rd greatly reduced in height, less broadly expanded,
elevated portion lower, gradually descending over anterior half.
Columellar and palatal walls with thick, rounded callus, extending
up through 4th palatal. Columellar barrier a broad, low, recessed,
serrated ridge parallel to plane of coiling. Palatal barriers 4,
extending more than one-eighth whorl, plus four accessory traces:
lower very high, bulbously expanded above, sharply descending
almost to lip edge over anterior half; 2nd slightly lower and less
broadly rounded above; 3rd intermediate in height, as expanded
above as 1st; 4th supraperipheral, a broad, V-shaped ridge,
moderately recessed, with sharp anterior descension. Accessory traces
very short, stopping inside callus edge, located between columellar
and 1st palatal, then between each pair of palatals. Height of
holotype 1.02 mm., diameter 1.73 mm.
Holotype — Gambier Islands: Mangareva, Aukena
Islet, Station 102, first cave east of gap. Collected by
Donald Anderson on May 28, 1934. BPBM 138757.
Range.— Known only from the type collection.
Paratypes.—Same as list of material.
Material.— Mangareva: Aukena Islet, first cave
(Station 102) east of gap (228 specimens, BPBM 9669,
BPBM 138757).
Remarks.— The palatal traces were accidentally
omitted from the figures of the holotype and the width
of the ribbing is much too narrow. Otherwise Figure
63a is an accurate representation of the type. Because
of the minute size and clogged apertures, no data is
available on the variation in palatal trace numbers.
The parietal trace situation was checked in only 20
individuals for the same reason.
The barrier length and numbers are very close to
the features found in Anceyodonta, but the umbilical
form, lack of secondary sculpture, crowded ribbing,
and basic appearance combine to place micro, in
Minidonta.
Minidonta hendersoni, new species (Cooke & Solem).
Figures 63c-d; 64a-b.
Diagnosis.— Shell slightly smaller than average, diameter 1.85-
2.45 mm. (mean 2.16 mm.), with 4l/2-5M> normally coiled whorls.
Apex and spire markedly and evenly elevated, last whorl descending
a little more rapidly, H/D ratio 0.575-0.685 (mean 0.621). Umbilicus
open, V-shaped, regularly decoiling, contained 3.09-4.35 (mean 3.67)
times in the diameter. Postnuclear whorls with high, prominent,
slightly protractively sinuated radial ribs, 75-95 (mean 82.9) on the
body whorl, whose interstices are about twice their width. Micro-
sculpture of fine radial riblets, four to six between each pair of major
ribs, with much finer and more crowded spiral riblets. Sutures
impressed, whorls strongly rounded above, laterally compressed,
umbilical margin very strongly rounded. Aperture ovate, compressed
laterally, inclined about 10° from shell axis. Parietal barriers 3,
extending less than one-quarter whorl, plus one accessory trace
above upper tooth: upper parietal a lower than usual bladelike ridge,
posterior half expanded and serrated, with sharp anterior descension;
2nd with posterior three-eighths equal in height to 1st. anterior
quarter threadlike; 3rd greatly reduced in height posteriorly, anterior
half threadlike. Accessory trace very inconspicuous, a recessed thread
located near parietal-palatal margin. Columellar barrier a low.
deeply recessed, threadlike ridge, in gerontic individuals completely
hidden by heavy callus. Palatal barriers 4. extending about one-
eighth whorl, upper reduced, plus one accessory trace: 1st basal in
position, high, bladelike, rather sharp descension over anterior half;
2nd slightly more expanded above with more gradual anterior
descension; 3rd with more gradual anterior descension, posterior
elevated portion proportionately shorter; 4th a less deeply recessed,
V-shaped ridge, much lower than 3rd, accessory trace inconspicuous
and threadlike, deeply recessed, located much nearer to 4th palatal
than to parietal-palatal margin. Older individuals have a strong
rounded callus extending from columellar wall to 4th palatal, but
not above latter.
The heavy palatal callus and rather widely open
umbilicus combine with the presence of an upper
parietal trace to readily separate Minidonta hender-
soni from other species of the genus. The much larger
M. anatonuana and M. haplaenopla are most similar
in general aspect, but they have narrower umbilici, no
parietal traces, and quite different sculpture. M.
taunensis is the same size and has nearly identical
barriers, but is a much more depressed shell with finer
sculpture and a more marked internal constriction of
the umbilicus. The Mangarevan M. micra is smaller
(mean diameter 1.73 mm.), with coarser sculpture (60.8
ribs on the body whorl), and a narrower umbilicus
(mean D/U ratio 4.99).
Description.— Shell very small, with 5'4 normally coiled whorls.
Apex and spire strongly elevated, slightly rounded above, last whorl
descending a little more rapidly, H/D ratio 0.638. Apical whorls l'/2,
sculpture of fine radial riblets, usually with one microrib between
each pair and rather crowded spiral microribbing. Postnuclear whorls
with high, V-shaped, rather prominent radial ribs, 95 on the body
whorl, whose interstices are about twice their width. Microsculpture
of fine radial riblets, four to six between each pair of major ribs,
crossed by much finer and more crowded spiral riblets that are
barely visible under 96 x magnification. Sutures impressed, whorls
strongly rounded above and on umbilical margin, slightly compressed
laterally. Color reddish-yellow, without darker markings. Umbilicus
broadly V-shaped, regularly decoiling, contained 3.83 times in the
diameter. Aperture ovate, compressed laterally, inclined about 10°
from shell axis. Parietal barriers 3, extending a little more than
three-eighths whorl, expanded and serrated above posteriorly: upper
high, bladelike, gradually descending over anterior third; 2nd with
anterior third threadlike, posterior three-eighths equal in height to
1st; 3rd greatly reduced in height posteriorly, with anterior
threadlike portion proportionately longer. Columellar barrier a small
threadlike trace recessed behind edge of columellar-basal callus.
Palatal barriers 4, extending one-eighth whorl: lower basal in
position, high and bladelike, expanded and serrated posteriorly, with
rather sharp anterior descension; 2nd slightly lower, with shorter
posterior expanded portion and more gradual anterior descension;
3rd palatal equal in height to 1st, with more gradual anterior
descension; 4th palatal a much lower, V-shaped ridge situated
opposite and pointing towards upper parietal. Accessory traces
located between palatals 2 and 3, 3 and 4, and above 4th barrier. A
heavy, rounded callus extends from columellar wall to 4th palatal.
Height of holotype 1.45 mm., diameter 2.27 mm.
Holotype.— Henderson Island: northwest part of
island (Station 254) on a flat hillside at 15 ft.
elevation. Collected on rotting sticks and under stones
by Donald Anderson on June 20, 1934. BPBM 149858.
Range.— Henderson Island at several scattered
localities.
Paratypes.—Same as list of material.
Material.— Henderson Island: northwest part
(Stations 219, 222, 223, 231, 233, 236, 241, 243, 244, 246,
SYSTEMATIC REVIEW
135
252, 254) under rotting vegetation and stones (506
specimens, BPBM 149428-9, BPBM 149461, BPBM
149470, BPBM 149573-4, BPBM 149602, BPBM
149631, BPBM 149708, BPBM 149712-3, BPBM
149729, BPBM 149756, BPBM 149830, BPBM 149858).
Remarks.— Dead specimens were common at nu-
merous stations on different parts of Henderson
Island, but living specimens were found only at
Stations 219 and 243. Unfortunately, most of these
were immature, but some account of the anatomy
could be prepared.
The shells had surprisingly little variation in size,
shape, and apertural barriers, the only exception was
the presence in some individuals of the small lower
palatal traces, and variation in the development of the
columellar and basal callus. In gerontic individuals,
particularly those from Station 236, the callus was
extremely heavy and covered the columellar trace
completely. In less aged individuals the columellar
trace could be seen lying just in back of the posterior
callus edge.
This species is obviously related to the Mangare-
van Minidonta micro., the differences being indicated
above under the "Diagnosis." Henderson Island is an
uninhabited, raised coral island of makatea. The
northern end is about 2'/2 miles wide, tapering after
about 5 miles to a southern point. Vegetation covers
the entire island up to its maximum elevation of about
100 ft. Surprisingly enough, in addition to this endemic
endodontid, Henderson Island also has the endemic
zonitid, Diastole glaucina H. B. Baker (1938b, p. 50),
and a tornatellinid, Tubuaia hendersoni Kondo (1962,
pp. 36-38).
Description of soft parts.— Foot and tail typical. Sole undivided,
extending slightly up side of foot. Pedal grooves typical, suprapedal
less distinct, no caudal horn or middorsal groove visible. Slime
network weak on head region. Head retracted partly into pallial
cavity.
Body color light yellow-white, without darker markings.
Mantle collar simple, without glandular extension onto pallial
roof. Pneumostome in normal position, no mantle lobes developed.
Pallial region extending apically a trifle less than one-half whorl,
flattened length about 2.04 mm. Lung roof clear, without granula-
tions. Kidney (K) typical, about 0.69 mm. long, base abutting on
loop of intestine, upper margin lying along hindgut, about 0.37 mm.
from base to anterior end. Ureter (KD) prominent, reflexed with
opening next to hindgut at anterior end of rectal kidney margin.
Heart (H) about one-third length of kidney, lying next to middle
portion of kidney, not parallel to hindgut. Principal pulmonary vein
(HV) very faint, without branching. Hindgut (HG) extending about
one-eighth whorl above apex of kidney, paralleling parietal-palatal
margin to anus.
Ovotestis poorly preserved, a small number of rather large
follicles (some with developing ova?), strung along a faintly
iridescent collecting duct, imbedded above stomach-intestine
reflexion. Hermaphroditic duct (GD, fig. 64a) typical, slightly
iridescent, swollen in midportion, narrowing abruptly just before
reflexion to albumen gland. Albumen gland (GG) lying between
kidney base and stomach, composed of comparatively few and
proportionately large alveoli, head of spermatheca lying against
lower edge. Talon (GT) long and slender, with small apical head,
imbedded in albumen gland, slightly enlarged after junction with
hermaphroditic duct, opening into head of prostate and uterus.
Prostate (DG) of large acini opening into narrow tube appressed to
wall of uterus, only a single row of acini present. Uterus (UT) a
swollen, thin-walled tube without clearly differentiated sections,
merging into free oviduct without demarcation.
Vas deferens (VD) originating from tube of prostate, passing
down to penioviducal angle, then reflexed up side of penis to insert
subapically on penis head. Penial retractor (PR) arising from
diaphragm just above point of stomach origin, inserting directly on
head of penis. Penis (P) elongated, slender, twisted, length about
1.38-1.60 mm., internally (fig. 64b) with two simple pilasters, vas
deferens entering just below apical union of pilasters in V formed by
their union. Atrium (Y) rather long.
Free oviduct (UV) tapering gradually from uterus, distinctly
wider than vas deferens. Spermatheca (S) with head reaching
albumen gland, slender shaft bound to prostate tube and uterus
junction, free on lower portion, joining free oviduct just above atrial
entrance. Vagina (V) effectively absent due to late union of free
oviduct and spermatheca.
Free muscle system typical.
Buccal mass and esophagus without noticeably different
features. Stomach starting about one-eighth whorl above apex of
pallial cavity, extending apically for one whorl before reflexing into
intestine. Intestine typical, coiling pattern occupying an eighth of a
whorl between pallial cavity and stomach.
Jaw and radula not satisfactorily mounted.
(Based primarily on BPBM 149428, one specimen in shell 1.68
mm. in diameter with 4Ve whorls, remaining previously extracted.)
GROUP OF Minidonta micraconica
Minidonta micraconica, new species. Figure 65
a-e.
Diagnosis.— Shell very small, diameter 1.95-2.05 mm. (mean 2.00
mm.), with 45/8-5V& rather tightly coiled whorls. Apex and spire
moderately and evenly elevated, last whorl descending more rapidly,
H/D ratio 0.560-0.597 (mean 0.575). Umbilicus narrow, U-shaped,
last whorl decoiling more rapidly, contained 4.42-6.78 times (mean
5.53) in the diameter. Postnuclear sculpture of prominent, broad,
rounded, slightly protractively sinuated radial ribs, 65-70 (mean 67.3)
on the body whorl, whose interstices are less than twice their width.
Microsculpture a lattice of extremely fine coequal radial and spiral
riblets, eight to twelve radials between each pair of major ribs.
Sutures impressed, whorls compressed laterally above periphery and
basally, columellar margin slightly protruded. Aperture ovate,
columellar margin prolonged, inclined about 5° from shell axis.
Parietal barriers 3, lower greatly reduced, with one accessory trace,
extending about three-sixteenths of a whorl: upper a high, thin
bladelike lamella with gradual descension over anterior quarter,
middle two-thirds with an accessory blade, strongly expanded and
serrated (fig. 65d, e) pointing toward or slightly above 3rd palatal
barrier; 2nd slightly longer than 1st, extending further anteriorly
with more gradual descension, posterior third strongly expanded and
serrated; 3rd parietal a low lamellar ridge, less than half length of
2nd, nearly identical in shape to that barrier. Accessory trace a
recessed thread, located midway between upper parietal and parietal-
palatal margin. Columellar barrier a low to moderate crescentic
ridge, parallel to plane of coiling, slightly recessed. Palatal barriers 5,
high, extending less than one-eighth whorl, expanded and serrated
above, plus two accessory traces: lower a high crescentic ridge,
descending sharply to lip edge, twisted at anterior end, located at
baso-columellar margin; 2nd slightly lower, with more gradual
descension, more bladelike in form; 3rd equal in height to 1st, with
rather gradual anterior descension, only slightly recessed; 4th
reduced in height, a low lamellar blade, slightly recessed, located
nearly on periphery; 5th identical to 4th, located above periphery.
Accessory traces short, located between 1st and 2nd, 2nd and 3rd
palatals.
FIG. 64. Anatomy of Minidonta, Mautodontha, Rhysoconcha, and Ruatara: a-b, Minidonta hendersoni. Henderson Island. BPBM
149428. a, genitalia; 6, interior of penis; c-d, Mautodontha (M.) zimmermani. Mt. Aorai, Tahiti, Society Islands. BPBM 145293. c,
terminal genitalia; d, interior of penis; e, Mautodontha (M.) aoraiensis. Mt. Aorai, Tahiti, Society Islands. BPBM 145536. Terminal
genitalia; f-g, Rhysoconcha variumbilicata, Maitua, Rapa, Austral Islands. BPBM 138337. /, genitalia; g, interior of penis; h-i, Ruatara
oparica normalis. Mt. Ruatara, Rapa, Austral Islands. BPBM 143492. h, genitalia; i, interior of penis; j, Ruatara oparica reductidenta,
Maitua, Rapa, Austral Islands. BPBM 137609. Penial complex. Scale lines as marked. (See Appendix for explanation of abbreviations.)
136
SYSTEMATIC REVIEW
137
The bifid upper parietal barrier immediately
separates Minidonta micraconica from most other
Austral Island endodontids. Species with similar
barrier structure include many of the much larger
Hawaiian Endodonta, and the closely related Min-
idonta gravacosta, which has only 2 major parietals, a
much lower spire and much wider umbilicus.
Description.— Shell very small, with 4% rather tightly coiled
whorls. Apex and spire moderately and evenly elevated, last whorl
descending more rapidly, H/D ratio 0.574. Apical sculpture eroded.
Postnuclear whorls with broad, prominent, rounded, slightly protrac-
tively sinuated radial ribs, 65 on the body whorl, whose interstices
are less than twice their width. Microsculpture extremely fine, a
lattice of coequal radial and spiral riblets, eight to twelve between
each pair of major ribs. Sutures impressed, whorls strongly rounded,
compressed laterally above periphery and on basal margin, colu-
mellar wall protruded. Color light reddish-yellow above periphery,
base and apex bleached white. Umbilicus narrow, U-shaped, last
whorl decoiling more rapidly, contained 6.78 times in the diameter.
Aperture ovate, inclined about 5° from shell axis, columellar margin
prolonged. Parietal barriers 3, first 2 extending three-sixteenths of a
whorl, 3rd greatly reduced, plus one superior accessory trace: upper
parietal long, with rather sharp anterior descension, broken off above
for most of length; 2nd a high, bladelike lamella, posterior third
expanded and serrated, with more gradual anterior descension; 3rd
greatly reduced, a short, crescentic, deeply recessed ridge lying along
posterior portion of 2nd tooth. Accessory lamella a very inconspic-
uous threadlike trace above 1st parietal. Columellar barrier a broad,
rather recessed, crescentic ridge parallel to plane of coiling. Palatal
barriers 5, extending less than one-eighth whorl, plus two accessory
traces: lower at baso-columellar margin, very high, expanded and
serrated above, descending abruptly to lip edge; 2nd slightly lower,
anterior parts broken off; 3rd as high as 1st, slenderer, with sharp,
but not plunging anterior descension; 4th located near periphery,
broken off above; 5th supraperipheral, a bladelike ridge with more
gradual anterior descension than 3rd, rather low. Two accessory
traces, a threadlike, inconspicuous ridge between 2nd and 3rd
palatals, plus a broader, higher ridge between 1st and 2nd palatals.
Height of holotype 1.15 mm., diameter 2.01 mm.
Holotype.— Austral Islands: Raivavae, Station 652,
one-quarter mile east of Anatonu village at 50-150 ft.
elevation. Collected on a hillside by Yoshio Kondo and
Donald Anderson on August 11, 1934. BPBM 147338.
Range.— Near Anatonu village, Raivavae, Austral
Islands.
Paratypes— Same as list of material.
Material.— Raivavae: hillside one-quarter mile east
(Station 652) of Anatonu village at 50-150 ft. elevation
(4 specimens, BPBM 147338).
Remarks.— The type specimen, unfortunately, has
several apertural barriers broken, but is by far the best
preserved example in terms of sculpture. Detail
sketches (fig. 65d, e) of the upper parietal in a
paratype compensate for the missing portions in the
holotype.
The bifid upper parietal is almost unique among
Austral Island species, although common in Hawaiian
Cookeconcha and Endodonta.
Minidonta gravacosta, new species. Figure 65f-h.
Diagnosis. -Shell very small, diameter 1.79-2.09 mm. (mean 1.97
mm.), with 43/4-5'/4 rather tightly coiled whorls. Apex flat to barely
elevated, lower whorls of spire descending rather rapidly, H/D ratio
0.424-0.525 (mean 0.466). Umbilicus open, U-shaped, last whorl often
decoiling a little more rapidly, contained 3.53-4.92 (mean 3.99) times
in the diameter. Postnuclear sculpture of prominent, broad, high,
slightly protractive radial ribs, 59-83 (mean 71.2) on the body whorl,
whose interstices are 1-2 times their width. Microsculpture a lattice
of very fine radial riblets, five to nine between each pair of
major ribs, crossed by distinctly finer and more crowded spiral
riblets. Sutures deep, whorls strongly rounded above and on basal
margin, strongly compressed laterally below periphery. Aperture
compressedly ovate, inclined less than 5° from shell axis. Parietal
barriers 2, extending about three-sixteenths of a whorl: upper a high,
thin, bladelike lamella with gradual descension over anterior third,
posterior half with a downwards pointing accessory blade, expanded
and serrated above; 2nd parietal a very broadly expanded ridge,
posterior half equal in height to 1st and serrated above, anterior
third much lower. A very weak, deeply recessed, columellar barrier
apparently usually present. Palatal barriers 5, extending one-eighth
whorl, plus one (67 per cent) or two (33 per cent) accessory traces:
lower at baso-columellar margin, very high and broad, abruptly
descending to lip margin, crescentic in form; 2nd markedly lower, a
broad, bladelike ridge, with more gradual anterior descension,
expanded and serrated above; 3rd nearly equal in height to 1st,
somewhat recessed, expanded and serrated above; 4th a shorter,
greatly reduced lamellar ridge, moderately recessed, slightly subpe-
ripheral; 5th same form and length as 4th, much higher, located
above periphery. First accessory trace a threadlike ridge to bladelike
lamella, expanded and serrated above, located between 1st and 2nd
palatals. Second accessory trace, when present, a very short
threadlike trace located between 2nd and 3rd palatals.
The Raivavae Minidonta micraconica is very
closely related, but differs in being higher (mean H/D
ratio 0.575), with a narrower umbilicus (mean D/U
ratio 5.53), 3 parietals and one accessory trace, plus a
quite distinct columellar barrier. Minidonta grav-
acosta has only 2 parietals, a very small, deeply
recessed, columellar barrier, much lower spire (mean
H/D ratio 0.466) and a wider umbilicus (mean D/U
ratio 3.99). No other species of Minidonta have a bifid
upper parietal.
Description.— Shell very small, with 5% rather tightly coiled
whorls. Apex and spire slightly and evenly elevated, last whorl
descending more rapidly, H/D ratio 0.476. Apical whorls l'/2,
sculpture of fine, rather crowded radial riblets, with a microsculpture
of one microradiat riblet between the primary radials and very fine
microspirals. Postnuclear whorls with broad, prominent, high,
slightly protractive radial ribs, 65 on the body whorl, whose
interstices are only slightly greater than their width. Microsculpture
of five to six radials between each pair of major ribs, crossed by finer
and more crowded spiral riblets. Sutures deep, whorls strongly
rounded above and on basal margin, strongly compressed laterally
below periphery, Color light yellow-white, without darker markings.
Umbilicus open, U-shaped, slightly and regularly decoiling, contained
3.93 times in the diameter, margin markedly shouldered. Aperture
elongate-ovate, laterally compressed, inclined less than 5° from shell
axis. Parietal barriers 2, extending three-sixteenths of a whorl: upper
high, quite prominent, gradual descension on anterior third, posterior
half with downwards pointing accessory blade, grossly expanded and
serrated above; 2nd a much lower barrier, very broadly expanded
and serrated above. Columellar barrier a very low, deeply recessed,
threadlike ridge, not visible in direct frontal view. Palatal barriers 5,
extending one-eighth whorl, plus two accessory traces: lower at baso-
columellar margin, high, quite thick, abruptly descending to lip edge;
2nd a much lower, bladelike lamella, somewhat expanded above,
slightly recessed, with much more gradual anterior descension; 3rd
same shape as 2nd, as high as 1st; 4th a low, moderately recessed
lamellar ridge, much smaller than 3rd; 5th higher than 4th, but lower
than 2nd, a recessed lamellar ridge. Accessory trace between 1st and
2nd palatals nearly equal in height to 4th palatal, but much shorter;
trace between 2nd and 3rd palatals a very short, raised threadlike
ridge. Height of holotype 0.99 mm., diameter 2.07 mm.
FIG. 65. a-e, Minidonta micraconica, new species, a-c, Station 652, Raivavae, Austral Islands. Holotype. BPBM 147338; d-e, detail of 1st
parietal lamella, Station 652, Raivavae, Austral Islands. Paratype; f-h, Minidonta gravacosta, new species. Station 622, Raivavae, Austral
Islands. Holotype. BPBM 147098. Scale lines equal 1 mm. (a-e, MM; f-h, SG).
138
SYSTEMATIC REVIEW
139
Holotype.— Austral Islands: Raivavae, Station 622,
in a hau and lime thicket at Ahuoivi Point under dead
hau leaves. Collected by Yoshio Kondo, Donald
Anderson, and C. M. Cooke, Jr. on August 9, 1934.
BPBM 147098.
Range.— Known from two lowland stations on
Raivavae Island.
Paratypes.— Same as list of material.
Material.— Raivavae: thicket at Ahuoivi Point
(Station 622) under dead hau leaves (39 specimens,
BPBM 147098, BPBM 142175); subfossil deposit at
Raiavua (Station 547) at 5 ft. elevation, about 10-30 ft.
inland (2 specimens, BPBM 146170).
Remarks.— Most specimens were not sufficiently
cleaned to enable sighting of the recessed columellar
barrier. It may be absent in a fair proportion, but this
could not be checked.
GROUP OF Minidonta rotellina
Minidonta rotellina (Pease, 1870). Figure 62e-f.
Pithys rotellina Pease, 1870, Jour, de Conchy!., 18, pp. 393-394 -
Aitutaki, Cook Islands.
Pitys rotellina Pease, 1871, Proc. Zool. Soc. London, 1871, pp. 453,
474; Garrett, 1881, Jour. Acad. Nat. Sci., Philadelphia, 8, (4), p.
390.
Helix (Pithy*) rotellina (Pease), Pfeiffer, 1876, Monog. helic. viv.,
7, p. 262.
Helix (Endodonta) rotellina (Pease), Tryon, 1887, Man. Conchol.,
(2), 3, p. 60, pi. 11, figs. 82-83.
Endodonta (Thaumatodon) rotellina (Pease), Pilsbrv, 1893, op.
cit.. (2), 9, p. 27.
Diagnosis.— Shell very small, diameter 1.83-2.19 mm. (mean 1.97
mm.), with 5-6 tightly coiled whorls. Apex slightly, spire markedly
elevated, last whorl descending at same rate, H/D ratio 0.539-0.611
(mean 0.573). Umbilicus quite constricted, last whorl dec-oiling more
rapidly, contained 5.29-8.21 times (mean 7.10) in the diameter.
Sculpture of vertical, extremely fine and crowded radial ribs, too
numerous for accurate counting, occasionally a slightly finer radial
riblet between each pair of major ribs and barely visible, extremely
crowded spiral riblets. Sutures deep, whorls evenly rounded on outer
margin, slightly compressed basallv. Aperture elongate-ovate, with
smoothly rounded margin, parallel to shell axis. Parietal barriers 3,
extending one-quarter whorl: upper a very high, thin lamella,
posterior two-thirds serrated and strongly expanded, anterior quarter
with very gradual anterior descension; 2nd with posterior third about
half as high as 1st, anterior half threadlike; 3rd with posterior
portion markedly lower than 2nd, otherwise identical. Columellar
wall with single broad, low rounded ridge, surmounting callus nearly
to lip edge and slightly slanted down from plane of coiling. Palatal
barriers 2, extending about three-sixteenths of a whorl, often (about
33 per cent) with a faint, short peripheral trace: lower basal in
position, a raised V-shaped to rounded ridge, rather deeply recessed;
2nd a very high bladelike lamellar ridge, serrated and strongly
expanded above, with very gradual anterior descension, much less
recessed than 1st palatal. Palatal trace, when present, located at
periphery, undoubtedly the remnant of a former 3rd palatal lamella.
The absence of major radial sculpture, minute
size, strongly constricted umbilicus and reduced num-
ber of palatal barriers at once separate Minidonta
rotellina from the other Society and Cook Island
species. No other Minidonta has such fine sculpture.
The irregular spacing between the parietal barriers is
equally distinctive.
Description.— Shell minute, with 6 tightly coiled whorls. Spire
markedly elevated, apex slightly flattened, H/D ratio 0.606.
Embryonic whorls IVs, sculpture eroded, remaining whorls with
extremely closely spaced, fine, lamellate, vertical radial ribs that are
much too numerous to count. Microsculpture consisting of a single
radial riblet between the scarcely larger radial ribs and barely visible,
quite crowded spiral ribbing. Sutures deep, whorls moderately
rounded above, slightly flattened on basal margin. Umbilicus narrow,
very constricted, contained 5.54 times in the diameter. Shell dark
yellowish white with extensive but irregular reddish flammulations.
Aperture ovate, somewhat flattened laterally and basally, parallel to
shell axis. Parietal barriers 3, extending slightly more than one-
quarter whorl: upper high and lamellate for posterior three-quarters,
serrated and grossly expanded above, gradually descending an-
teriorly: 2nd with anterior two-thirds threadlike, posterior quarter
about half the height of 1st; 3rd similar to 2nd, but with posterior
portion much lower. Columellar barrier a low, rounded recessed ridge
on a relatively thin callus, almost parallel to plane of coiling. Major
palatal barriers 2, extending three-sixteenths of a whorl: lower a
moderately high lamellate ridge, serrated and broadly rounded
above, extending to posterior edge of apertural callus; 2nd a very
high lamellate ridge, strongly expanded and serrated above,
extending much nearer to apertural edge. Height of lectotype 1.33
mm., diameter 2.19 mm.
Lectotype.— Cook Islands: Aitutaki. Collected by
Andrew Garrett. BPBM 2312.
.Range.— Aitutaki.
Paratypes. -BPBM 2312.
Material. -Aitutaki (25 specimens, BPBM 2312,
FMNH 116988, Zurich, SMF 165459).
Remarks.-Garrett (1881, p. 390) reported that
both Mautodontha imperforata and Minidonta rotell-
ina were common in coastal forests on Aitutaki.
Although Peter Buck collected a few Mautodontha
imperforata in 1929, no specimens of Minidonta
rotellina have been taken since the early 1880's.
In several respects the apertural barriers are
unusual. Proportionately, the 1st parietal is grossly
enlarged in size, while the nearly opposite 3rd palatal
either is reduced to a barely visible trace or usually is
absent. Possibly as a concommitant of the inward
apertural prolongation, the columellar barrier and 1st
palatal are much smaller than usual and the 2nd
palatal is enlarged. Thus enlargement in the 1st
parietal and 2nd palatal is balanced by reductions in
the 1st and 3rd palatals and columellar ridge. Also, the
distance between the 1st and 2nd parietals is more
than twice the distance between the 2nd and 3rd
parietals, where in most other species of endodontids,
the distance between parietal barriers is essentially
identical.
The general similarities (fig. 61) of Mautodontha
imperforata to Minidonta rotellina are misleading.
The former has much less reduced sculpture, the
apertural barriers split in several cases, and a different
pattern of whorl coiling.
GROUP OF Minidonta anatonuana
Specimens of this complex are relatively similar
and show slight-to-moderate overlap in almost every
140
SOLEM: ENDODONTOID LAND SNAILS
2.04
1.91
1.77
1.64
1.51
1.38
.25
planulata
haplaenopla
w anatonuana
DDD
o
•fr
2.43
2.69
2.96
3.22
3.48
Diameter in mm.
FIG. 66. Correlation of height and diameter in Minidonta anatonuana, M. haplaenopla, and M. planulata.
meristic character. The columellar sulcus of Mini-
donta sulcata (fig. 68f) at once identifies that species,
but the others can be confused. Plotting of the height
and diameters for M. planulata, M. haplaenopla, and
M. anatonuana (fig. 66) shows the last two share a
common pattern of growth, but M. anatonuana is
smaller, while M. planulata has an altered pattern. A
similar comparison of the D/U ratio and diameter (fig.
67) will assist in separating doubtful examples. With
reference to these charts and barrier structure, even
worn examples can be identified with certainty.
Minidonta anatonuana, new species. Figure
68a-c.
Diagnosis.— Shell very large, diameter 2.78-3.25 mm. (mean 3.02
mm.), with 5-6 normally coiled whorls. Apex and spire markedly
elevated, last whorl descending a little more rapidly, H/D ratio
0.500-0.633 (mean 0.577). Umbilicus narrow, U-shaped, last whorl
decoiling slightly more rapidly, contained 4.90-7.73 times (mean 5.87)
in the diameter. Postnuclear whorls with high, prominent, rounded,
protractively sinuated radial ribs, 83-94 (mean 89.5) on the body
whorl, whose interstices are 2-3 times their width. Microsculpture a
lattice of fine radial riblets, three to five between each pair of
major ribs, crossed by finer and more crowded spiral riblets. Sutures
deep, whorls strongly rounded above, flattened to very slightly
concave above periphery, evenly rounded and somewhat compressed
below periphery. Aperture ovate, noticeably flattened above pe-
riphery, inclined about 10° from shell axis. Parietal barriers 3,
extending more than one-quarter whorl, first 2 quite large: upper
parietal a very high, thin, bladelike lamella, very slightly expanded
above, with gradual descension until anterior eighth; 2nd parietal
with posterior half equal in height to 1st, anterior quarter to third a
low bladelike lamella, extending further than 1st; 3rd parietal greatly
reduced in height, a bladelike to V-shaped recessed ridge lying along
posterior half of 2nd parietal. Columellar barrier absent, although 1st
palatal located at baso-columellar margin. Palatal barriers 4,
prominent, extending three-sixteenths of a whorl, often with an
accessory trace: lower at baso-columellar margin, a low, bladelike
lamella with gradual anterior descension; 2nd much higher, longer,
less recessed, with slightly more gradual anterior descension; 3rd
quite high, pointing between 1st and 2nd palatals, thin, nearly
reaching lip margin, with sharper anterior descension; 4th suprape-
ripheral, a reduced V-shaped to lamellar ridge, deeply recessed and
shortened. Palatal trace, when present, situated between 1st and 2nd
palatals.
The palatal barriers of Minidonta anatonuana
relate it to the inexpectans-manuaensis-sulcata
complex, from which it differs by its much larger size,
smaller umbilicus and lack of a columellar barrier. M.
haplaenopla has finer and more crowded ribs and
usually less than 4 palatals.
Description.— Shell small, with 5'4 normally coiled whorls. Apex
and spire strongly elevated, last whorl descending a little more
rapidly, H/D ratio 0.568. Embryonic whorls l'/2, only trace of typical
radial and microsculpture remaining. Remaining whorls with high,
prominent, rounded, slightly protractively sinuated radial ribs, 94 on
the body whorl, whose interstices are less than twice their width.
Microsculpture a lattice of very fine radial and even finer spiral
riblets. Sutures deep, whorls strongly rounded above, flattened to
SYSTEMATIC REVIEW
141
o
ro
ctr
8.5
8.0
7.5
7.0
6.5
6.0
5.5
5.0
4.5
4.0
LJ planulata
^ anatonuana
"fa haplaenopla
D
D
D
D
I
I
I
243
2.69
3.22
2.96
Diameter in mm.
FIG. 67. Correlation of diameter and D/U ratio in Minidonta anatonuana, M. haplaenopla, and M. planulata.
3.48
slightly concave above periphery, compressed on low.er palatal
margin. Color leached from shell. Umbilicus quite narrow, U-shaped,
last whorl decoiling more rapidly, contained 5.50 times in the
diameter. Aperture ovate, flattened above, compressed below
periphery, inclined about 15° from shell axis. Parietal barriers 3,
extending more than one-quarter whorl: upper a very high, thin,
bladelike lamella, not expanded above, descending sharply at
anterior end; 2nd with posterior half as in 1st, anterior quarter a
raised, threadlike ridge; 3rd a low threadlike ridge along posterior
half of 2nd tooth. No columellar barrier. Palatal barriers 4, extending
more than one-eighth whorl, with one accessory trace: lower at baso-
columellar margin, a low lamellar ridge crossing callus and nearly
reaching apertural margin; 2nd much higher, pointing towards 2nd
parietal, an elevated lamellar ridge with gradual anterior descension,
nearly reaching lip margin; 3rd a quite high, bladelike lamella, with
very gradual anterior descension; 4th a deeply recessed, V-shaped
trace, supraperipheral. Accessory trace threadlike, short, located
between 1st and 2nd palatals, moderately recessed. Callus on
columellar and lower palatal wall rather thick. Height of holotype
1.65 mm., diameter 2.90 mm.
Holotype.— Austral Islands: Raivavae, Station 652,
one-quarter mile east of Anatonu village at 50-150 ft.
elevation. Collected by Yoshio Kondo and Donald
Anderson on August 11, 1934. BPBM 147384.
Range.— Near Anatonu village, Raivavae, Austral
Islands.
Paratypes.— Same as list of material.
Material.— Raivavae: one-quarter mile east of
Anatonu village (Stations 633, 636, 652) at 50-500 ft.
elevation (33 specimens, BPBM 147167, BPBM 147196,
BPBM 147384-5, BPBM 147387).
Remarks.— All specimens of Minidonta anaton-
uana were from subfossil deposits and the apertures
clogged with dirt. Not all individuals were cleaned
sufficiently to check the presence or absence of the
palatal trace, but about two-thirds of those checked
had the trace present.
The slight indication of a supraperipheral sulcus,
big barriers, and narrowly U-shaped umbilicus with
rapidly decoiling last whorl present an appearance
somewhat intermediate between Australdonta and
Minidonta. The form of the barriers is the same as in
M. inexpectans and M. manuaensis. M. anatonuana
lacks the sculpture and shell form of Australdonta.
The umbilical characters are those of Minidonta and
association with these species is the most logical choice
in classifying this species.
Minidonta sulcata, new species. Figure 68d-f.
Diagnosis.— Shell of average size, diameter 2.25-2.32 mm. (mean
2.28 mm.), with 5-5'/2 tightly coiled whorls. Apex and spire
e
def
FIG. 68. a-c, Minidonta anatonuana, new species. Station 652, Raivavae, Austral Islands. Holotype. BPBM 147384; d-f, Minidonta sulcata,
new species. Station 652, Raivavae, Austral Islands. Holotype. BPBM 215242. Scale lines equal 1 mm. (SG).
142
SYSTEMATIC REVIEW
143
moderately and evenly elevated, last whorl descending more rapidly,
H/D ratio 0.574-0.600 (mean 0.587). Umbilicus narrow, U-shaped,
last whorl decoiling slightly more rapidly, contained 4.00-5.00 times
(mean 4.50) in the diameter. Umbilical margin protruded into a
"beak", columellar wall with a strong sulcus. Postnuclear whorls
with high, rounded, prominent, vertically sinuated radial ribs, 105-
120 (mean 112.5) on the body whorl, whose interstices are about
twice their width. Microsculpture a lattice of fine radial riblets, three
to five between each pair of major ribs, crossed by very fine spiral
ribs, about half the size of radials. Sutures deep, whorls strongly
rounded above, slightly compressed laterally above and below evenly
rounded periphery, umbilical margin as described above. Aperture
ovate, inclined less than 5° from shell axis. Parietal barriers 2,
extending less than three-sixteenths of a whorl: upper a high
bladelike ridge with gradual anterior descension, posterior elevated
half serrated and expanded above; 2nd equal in height to 1st, longer,
with same shape, extending further anteriorly. Columellar barrier a
high, bladelike lamella, parallel to plane of coiling until just inside
aperture, suddenly descending anteriorly, nearly reaching lip margin.
Palatal barriers 4, 1st and 4th greatly reduced, 2nd and 3rd extending
about one-eighth whorl: 1st basal, an inconspicuous threadlike trace;
2nd a low lamellar ridge with gradual anterior descension, nearly
reaching lip edge; 3rd a high lamellar blade with sharper anterior
descension; 4th supraperipheral, an inconspicuous, recessed, V-
shaped ridge.
The striking columellar sulcus at once separates
Minidonta sulcata from the other species of Mini-
donta. The simplified set of barriers is basically like
that found in M. inexpectans, differing only in the
presence of a large columellar and only 2 parietal
barriers.
Description.— Shell very small, with 5 tightly coiled whorls. Apex
and spire moderately and evenly elevated, last whorl descending
more rapidly, H/D ratio 0.574. Embryonic whorls 1%, sculpture
completely eroded. Remaining whorls with high, prominent, rounded,
vertically sinuated radial ribs, 120 on the body whorl, whose
interstices are less than twice their width. Microsculpture of
extremely fine radial riblets, three to five between each pair of major
ribs, crossed by finer and more crowded spiral riblets. Sutures deep,
whorls strongly rounded, with lateral compression above and below
periphery. Umbilical margin with deep sulcus and protruding keel.
Color mainly leached from shell. Umbilicus narrow, U-shaped, last
whorl decoiling slightly more rapidly, contained 4.00 times in the
diameter. Aperture ovate, lip edge badly broken. Parietal barriers 2,
extending about three-sixteenths of a whorl: upper a high, bladelike
lamella, posteriorly serrated and expanded, anteriorly with gradual
descension; 2nd longer, extending somewhat further anteriorly,
identical in shape. Columellar barrier high, bladelike, abruptly
descending anteriorly, slightly angled downwards from plane of
coiling, nearly reaching lip edge. Palatal barriers 4, extending about
one-eighth whorl: lower a very inconspicuous threadlike trace, basal
in position; 2nd a moderate lamellar ridge with gradual anterior
descension; 3rd a much higher, bladelike lamella with sharper
anterior descension; 4th a shorter, deeply recessed V-shaped ridge,
supraperipheral. Height of holotype 1.28 mm., diameter 2.24 mm.
Holotype.— Austral Islands: Raivavae, Station 652,
one-quarter mile east of Anatonu village at 50-150 ft.
elevation. Collected on a hillside by Yoshio Kondo and
Donald Anderson on August 11, 1934. BPBM 215242.
Range.— Near Anatonu village, Raivavae, Austral
Islands.
Paratypes.— Same as list of material.
Material.— Raivavae: one-quarter mile east of
Anatonu village (Station 652) at 50-150 ft. elevation on
a dry hillside (4 specimens, BPBM 147384).
Remarks.— No important variation in barrier
structure was noted. While the sulcus and large
columellar barrier are diagnostic and make Minidonta
sulcata seem a highly distinctive species, the form of
the palatal barriers and shell shape indicate its close
relationship to M. inexpectans and M. manuaensis.
Minidonta haplaenopla, new species. Figure 69
d-f.
Diagnosis. — Shell rather large, diameter 2.28-3.01 mm. (mean
2.59 mm.), with 4%-5% normally coiled whorls. Apex flat, spire
slightly elevated, last whorl descending more rapidly, H/D ratio
0.506-0.608 (mean 0.563). Umbilicus narrow, open, U-shaped, only
slightly decoiling, contained 4.26-5.75 times (mean 5.06) in the
diameter. Postnuclear sculpture of prominent, narrow, slightly
protractively sinuated radial ribs, 91-125' (mean 109.6) on the body
whorl, whose interstices are 2-3 times their width. Microsculpture of
extremely fine radial riblets, four to seven between each pair of
major ribs, crossed by even finer and more crowded spiral ribs, with
a secondary sculpture of rather widely spaced spiral cords. Sutures
deep, whorls strongly rounded above, evenly rounded on compressed
outer margin, umbilical margin strongly rounded. Aperture
compressedly ovate, inclined about 5° from shell axis. Parietal
barriers 3, rarely 2 (9.5 per cent), extending one-quarter whorl: upper
a high bladelike lamella, gradually descending over anterior half; 2nd
with posterior eighth usually equal in height to 1st, expanded and
serrated, anterior half a high threadlike ridge; 3rd with posterior
section reduced in height, not expanded, anterior half a lower
threadlike ridge. No columellar barrier. Palatal barriers 3, extending
less than one-eighth whorl, low bladelike ridges: lower rather short,
basal in position, flat, expanded and serrated posteriorly, with very
gradual anterior descension; 2nd much higher, larger, with sharper
anterior descension, rather deeply recessed, tending towards crescen-
tic form above.
Smaller in size than M. anatonuana and M.
planulata, Minidonta haplaenopla differs from them
primarily in its reduced barrier complement and finer
sculpture, plus adding a secondary sculpture of spiral
cords. The absence of a columellar barrier also is a
distinguishing character.
Description. — Shell rather small, with 5% normally coiled
whorls. Apex nearly flat, spire strongly elevated, last whorl not
descending more rapidly, H/D ratio 0.561. Apical whorls 1%,
sculpture eroded. Postnuclear whorls with low, rounded, very closely
set, almost vertically sinuated radial ribs, 179 on the body whorl,
whose interstices are equal to their width. Microsculpture a lattice of
very fine radials and barely visible spirals, with a secondary
sculpture of rather inconspicuous spiral cords. Sutures deep, whorls
strongly rounded above and on umbilical margin, strongly
compressed laterally below periphery. Umbilicus, narrow, U-shaped,
last whorl decoiling slightly more rapidly, contained 5.23 times in the
diameter. Color light reddish-horn, with vague traces of lighter
markings. Aperture elongate-ovate, inclined slightly more than 5°
from shell axis. Parietal barriers 3, extending less than one-quarter
whorl, partly broken: upper with posterior quarter absent, anterior
portion a gradually descending, rather low, bladelike lamella; 2nd
with posterior third moderately elevated, anterior half threadlike;
3rd a low threadlike trace for entire length. No columellar barrier.
Palatal barriers 3, low and short: 1st a moderately recessed, short
crescentic lamellar trace; 2nd a less deeply recessed lamellar ridge
with gradual anterior descension; 3rd a much shorter, deeply recessed
lamellar trace. Height of holotype 1.68 mm., diameter 2.93 mm.
Holotype.— Austral Islands: Rurutu, Station 748,
Mato Naa cliffs at 250 ft. elevation. Collected dead by
'In one gerontic adult, 179 ribs.
abc
FIG. 69. a-c, Minidonta planulata, new species. Station 633, Raivavae, Austral Islands. Holotype. BPBM 147166; d-f, Minidonta
haplaenopla, new species. Station 748, Rurutu, Austral Islands. Holotype. BPBM 148129. Scale lines equal 1 mm. (MM).
144
SYSTEMATIC REVIEW
TABLE LXIV. - LOCAL VARIATION IN MINIDONTA
145
Number of
Name
Specimens Height
Diameter
H/D ratio
Whorls
D/U ratio
manuaensis
BPBM 188720,
4 0.96*0.040
1.68*0.052
0.572*0.0065
4+
5.28*0.295
BPBM 186774.
(0.89-1.08)
(1.59-1.82)
(0.563-0.590)
(4-4 1/4)
(4.79-6.13)
BPBM 186758
micra
BPBM 138757
20 1. 09*0. 014
1.73*0.011
0.625*0.0063
41/2-
4.99*0.114
(0.96-1.19)
(L 67-1. 89)
(0.563-0.667)
(4 1/4-4 3/4)
(3.61-5.88)
hendeisoni
BPBM 149574, -631,
-729, -858, -929
29 1.34*0.020
2.16*0.025
0.621*0.0048
5+
3.67*0.069
(1.16-1.59)
(1.85-2.45)
(0.575-0.685)
(4 1/2-5 1/2)
(3.09-4.35)
micraconica
BPBM 147388
4 1.15*0.028
2.00*0.022
0.575*0.0080
4 3/4+
5.53*0.515
(1.09-1.23)
(1.95-2.05)
(0.560-0.597)
(4 5/8- 5)
(4.42-6.78)
gravacosta
BPBM 147098
12 0. 92*0. 016
1.97*0.025
0.466*0.0095
5-
3.99*0.110
(0.83-1.03)
(1.79-2.09)
(0.424-0.525)
(4 1/2-5 1/4)
(3.53-4.92)
rotellina
BPBM 2312
6 1.14*0.044
1.97*0.051
0.575*0.0071
5 1/2
7.08*0.423
(1.04-1.33)
(1.84-2.19)
(0.562-0.609)
(5 1/4-6)
(5.54-8.13)
FMNH 116988
7 1.13*0.031
1.98*0.044
0.569*0.0100
53/8+
7.26*0.364
(1. 02-1. 27)
(1.84-2.19)
(0.539-0.611)
(5-5 5/8)
(5.29-8.21)
anatonuana
BPBM 147384
12 1.69*0.036
2.99*0.042
0.567*0.0104
5 3/8+
5.89*0.269
(1.46-1.92)
(2.78-3.25)
(0.500-0.631)
(5-5 1/2)
(4. 90-7. 73)
sulcata
BPBM ex 147384
3 1.39*0.057
2.28*0.033
0.587*0.0127
5 1/4+
4.50*0.502
(1.29-1.49)
(2.25-2.32)
(0.574-0.600)
(5-5 1/2)
(4. 00-5. 00)
haplaenopla
BPBM 148129
7 1.55*0.069
2.71*0.099
0.570*0.0132
51/4
5.06*0.114
(1.36-1.82)
(2. 32-3. 01)
(0.506-0.608)
(4 7/8-5 5/8)
(4.26-5.39)
BPBM 148686
7 1.37*0.043
2.46*0.042
0.555*0.0121
5-
5.05*0.178
(1.23-1.57)
(2.28-2.65)
(0.507-0.597)
(4 3/4-5 1/8)
(4.44-5.75)
pianola ta
BPBM 147166
6 1.62*0.030
3.26*0.075
0.495*0.0049
5
7.12*0.347
ex 147384
(1.49-1.69)
(2.98-3.41)
(0.484-0.517)
(4 3/4-5 1/8)
(6.37-8.42)
taunerisis
BPBM 140884
2 1.18*0.050
2.25*0.066
0.527*0.0020
51/8+
3. 36*0. 311
(1.13-1.23)
(2.19-2.32)
(0.525-0.529)
(5-5 3/8)
(3.05-3.67)
taiavensis
BPBM 138884
2 1.42*0.066
2.58*0.099
0.551*0.0050
51/2
6.11*0.707
(1.36-1.49)
(2.48-2.68)
(0.546-0.556)
(5 3/8-5 5/8)
(5.40-6.82)
Simula ta
BPBM 138698,
17 1.53*0.025
2.71*0.030
0.566*0.0082
51/8-
4.82*0.155
BPBM 138756
(1.39-1.79)
(2.45-2.88)
(0.518-0.658)
(4 3/4-5 5/8)
(3.96-6.31)
Yoshio Kondo and C. M. Cooke, Jr. on August 25,
1934. BPBM 148129.
Range.— Mato Naa area at 10-250 ft. elevation,
Rurutu, Austral Islands.
Paratypes.— Same as list of material.
Material.— Rurutu, Mato Naa area (Stations 748,
768, 792) at 10-250 ft. elevation (77 specimens, BPBM
148129, BPBM 148686, BPBM 148402).
Remarks.— The type is a relatively gerontic shell
in which size of the barriers is quite reduced, compared
with younger individuals, and the radial ribbing is very
crowded. Other gerontic specimens, two in number,
have the 3rd parietal lost and the 3rd palatal reduced
to a very slight trace. Also the entire palatal wall
becomes covered with a rather thick callus.
Specimens from Stations 748 and 792 differed
significantly (table LXIV) in respect to diameter (with
12 df, "t" = 2.3259), reflecting only the presence of
gerontic individuals in the set from Station 748. The
slight difference in H/D ratio is not significant ("t" =
0.8388). The name haplaenopla is derived from the
Greek words meaning "simply armed" and refers to
the undistinguished apertural barriers. The only slight
146
SOLEM: ENDODONTOID LAND SNAILS
decoiling of the last umbilical whorl and secondary
microsculpture are not the usual characters of Mini-
donta, but the pattern of the barrier structure is so
similar to M. inexpectans and M. manuaensis that I
have no hesitation about including M. haplaenopla in
this genus. The characters of M. haplaenopla begin to
approach those of Australdonta, which is quite
possibly a direct local derivative of Minidonta.
Minidonta planulata, new species. Figure 69a-c.
Diagnosis. — Shell extremely large, diameter 2.98-3.41 mm.
(mean 3.26 mm.), with 4%-5% normally coiled whorls. Apex and
spire evenly elevated, last whorl descending a little more rapidly,
H/D ratio 0.484-0.517 (mean 0.495). Umbilicus very narrow,
constricted, last whorl decoiling more rapidly, contained 6.37-8.42
times (mean 7.12) in the diameter. Postnuclear sculpture of
prominent, rounded, strongly protractively sinuated radial ribs, 88-99
(mean 94) on the body whorl, whose interstices are 2-5 times their
width. Microsculpture of low, fine, quite widely spaced radial riblets,
three to six between each pair of major ribs, crossed by barely
visible, crowded spiral riblets. Sutures deep, whorls evenly rounded
on outer margin, slightly compressed laterally above periphery,
flattened on basal margin, with very strongly rounded umbilical
margin. Aperture ovate, flattened basally, inclined slightly more
than 20° from shell axis. Parietal barriers 3, extending one-quarter
whorl: upper a high, bladelike lamella, posterior third weakly
expanded and serrated above, anterior end very sharply descending;
2nd with posterior elevated portion distinctly lower, but more
broadly expanded, anterior half a very low bladelike lamella; 3rd
parietal a low threadlike ridge, very weakly elevated posteriorly. No
columellar barrier. Palatal barriers 4, very low, extending about one-
eighth whorl: lower a raised threadlike ridge partly hidden behind
apertural callus, basal in position; 2nd equal in size to 1st, deeply
recessed; 3rd slightly higher and longer, a trifle less recessed; 4th a
very inconspicuous, short, deeply recessed, V-shaped trace.
The highly constricted umbilicus, lack of secon-
dary spiral sculpture, and absence of the suprape-
ripheral sulcus are the main characters separating
Minidonta planulata from Australdonta. The large
size, depressed shape, very narrow umbilicus, and
absence of a columellar barrier readily distinguish M.
planulata from the other Minidonta.
Description. — Shell of average size, with 5 normally coiled
whorls. Apex and spire slightly and evenly elevated, last whorl
descending a little more rapidly, H/D ratio 0.486. Apical sculpture of
fine, quite widely spaced radial ribs, with finer, more crowded spiral
riblets, radial sculpture becoming much more crowded at end of
apex. Postnuclear whorls with narrow, prominent, strongly protrac-
tively sinuated radial ribs, 99 on the body whorl, whose interstices
are 3-5 times their width. Microsculpture of fine, widely spaced
radial riblets, three to six between each pair of major ribs, crossed by
much finer and more crowded spiral riblets. Sutures impressed,
whorls evenly rounded on outer margins, slightly compressed
laterally above periphery, flattened on basal margin, umbilical
margin very strongly rounded. Umbilicus strongly constricted, U-
shaped, last whorl suddenly decoiling, contained 6.44 times in the
diameter. All color leached from shell. Aperture compressedly ovate,
flattened basally, inclined more than 20° from shell axis. Parietal
barriers 3, extending nearly one-quarter whorl: upper very high and
bladelike, posterior quarter serrated and weakly expanded with very
sharp anterior descension; 2nd with lower posterior portion, anterior
half a low lamellar ridge; 3rd a very low threadlike trace, not
expanded posteriorly. Columellar barrier absent. Palatal barriers 4,
extending one-eighth whorl, quite low and inconspicuous: lower
hidden behind apertural callus, a raised threadlike ridge; 2nd- a raised
lamellar ridge, rather deeply recessed; 3rd slightly higher, less deeply
recessed; 4th a short, very deeply recessed, V-shaped trace. Height of
holotype 1.65 mm., diameter 3.39 mm.
Holotype. — Austral Islands: Raivavae Island,
Station 633, one-quarter mile east of Anatonu village
at 50-150 ft. elevation. Collected on a hillside by
Yoshio Kondo and Donald Anderson on August 10,
1934. BPBM 147166.
Range. — Near Anatonu Village, Raivavae, Aus-
tral Islands.
Paratypes. — Same as list of material.
Material. — Raivavae: one-quarter mile east of
Anatonu village (Stations 633, 653) at 50-150 ft.
elevation (7 specimens, BPBM 147166, BPBM 147384).
Remarks. — Although agreeing with Australdonta
in size and general appearance, the presence of only 3
palatal barriers, constricted umbilicus, absence of
secondary spiral grooving, and lack of a supraperipher-
al sulcus in Minidonta planulata effectively dis-
tinguish it from Australdonta. Although by far the
largest Minidonta, the apertural and umbilical charac-
ters of M. planulata agree fully with more typical
species.
No significant variation was noted in the limited
material available.
GROUP OF Minidonta simulata
Minidonta taunensis, new species (Solem & Cooke).
Figure 70e-f.
Diagnosis. — Shell average in size, diameter 2.19-2.32 mm. (mean
2.25 mm.) with 5-5% normally coiled whorls. Apex flat, spire
slightly elevated, last whorl descending much more rapidly, H/D
ratio 0.525-0.529 (mean 0.527). Umbilicus open, U-shaped, last whorl
decoiling much more rapidly, contained 3.05-3.67 times (mean 3.36)
in the diameter. Postnuclear whorls with narrow, rounded, slightly
protractively sinuated radial ribs, 113 on the body whorl, whose
interstices are 2-3 times their width. Microsculpture of rather
prominent radial riblets, three to five between each pair of major
ribs, crossed by very fine and crowded, barely visible spiral riblets.
Sutures impressed, whorls strongly rounded above and on basal
margin, slightly compressed laterally. Aperture ovate, inclined about
10° from shell axis. Parietal barriers 3, extending more than one-
quarter whorl: upper a high, thin blade, weakly expanded above for
posterior three-quarters, anterior quarter much lower after abrupt
descension; 2nd equal in height to 1st for posterior five-eighths, more
expanded and serrated above, anterior third threadlike; 3rd with
posterior elevated portion less than half the height of 2nd, anterior
threadlike portion very short, stopping far back of anterior end of
2nd parietal. Columellar barrier a broad, low, crescentic ridge,
moderately recessed, with anterior end angled slightly downwards.
Palatal barriers 4, long, bladelike ridges, extending nearly three-
eighths whorl, plus one faint superior trace: lower a narrow bladelike
lamella, suddenly descending anteriorly to a threadlike extension;
2nd much higher, more broadly expanded and serrated, with more
gradual anterior descension, coming nearer to lip edge; 3rd distinctly
higher than 2nd, less recessed, with more gradual anterior descen-
sion; 4th a narrow, prominent, V-shaped ridge, much lower than 3rd
palatal, lying opposite upper parietal.
Although very similar in general appearance to
Mautodontha daedalea, the internally constricted
umbilicus, presence of a distinct columellar barrier,
very small size and much higher spire easily separate
ef
FIG. 70. a-d, Minidonta simulata, new species, a- b, Station 88, Aukena Islet, Mangareva, Gambier Islands. Holotype. BPBM 138698; c-d,
Station 102. Aukena Islet, Mangareva, Gambier Islands. A gerontic individual. BPBM 9409; e-f, Minidonta taunensis, new species. Station 90.
Tauna Islet. Mangareva. Gambier Islands. Holotype. BPBM 140884. Scale lines equal 1 mm. Drawings by YK reproduced through the courtesy
of Bernice P. Bishop Museum.
147
148
SOLEM: ENDODONTOID LAND SNAILS
Minidonta taunensis. Of the other Mangarevan spe-
cies, M. taravensis has much coarser ribbing, a 4th
parietal and a much narrower umbilicus; M. simulata
is larger, with more widely spaced ribbing, usually
lacks the columellar barrier and has one to two
accessory palatal traces.
Description.— Shell very small, with 5 normally coiled whorls.
Apex almost flat, lower whorls descending progressively more
rapidly. H/D ratio 0.525. Apical whorls l:l/«, sculpture of fine radial
riblets, microriblet between each pair of major ribs, and extremely
fine spiral riblets. Postnuclear whorls with narrow, rounded, slightly
protract ively sinuated radial ribs. 113 on the body whorl, whose
interstices are 2-3 times their width. Microsculpture of rather
prominent radial riblets, three to five between each pair of major
ribs, crossed by very fine and crowded spiral riblets. Sutures
impressed, whorls strongly rounded above and on basal margin,
slightly compressed laterally. Color light yellow-white, with regularly
spaced reddish markings, zigzagged and broadened on periphery,
narrowing and tending to coalesce on base of shell. Umbilicus
narrow, U-shaped, last whorl decoiling quite rapidly, contained 3.67
times in the diameter. Aperture ovate, slightly compressed laterally,
inclined about 10° from shell axis. Apertural barriers as described in
diagnosis above. Height of holotype 1.12 mm., diameter 2.17 mm.
Holotype.— Gambier Islands: Mangareva, Station
90, Tauna Islet. Collected from dead leaves by S.
Wight and Yoshio Kondo on May 28, 1934. BPBM
140884.
Range.— Known only from the type collection.
Paratype.-EPEM 140884.
Material.— Same as types (2 specimens).
Remarks.— Although a second trip was made to
Tauna Islet in search of additional material, only the
two specimens were found. Tauna Islet is third to the
southernmost of the chain of coral islets situated on
the outer reef west of the high islets in the Mangareva
group. It is about one-quarter mile long, a few hundred
feet wide, and about 6 ft. high. The islet in 1934 was
heavily covered by regular atoll vegetation with a
generous planting of coconuts. The only other snails
found on the islet belonged to wide-ranging "atoll"
species and none of the other Mangarevan endemics
were obtained. The presence there of a distinct species
of endodontid is quite surprising.
At first glance (fig. 70) Minidonta taunensis
would seem identical to M. simulata. The larger size at
a lower whorl count (table LXIII), higher spire,
narrower umbilicus, reduced parietal barriers, and
absence of the columellar barrier in M. simulata easily
distinguish them. Although not shown adequately in
the illustrations, M. simulata has fewer and more
widely spaced radial ribs. In the single paratype the
umbilicus is less constricted internally, although still
not showing the normal, regular decoiling seen in most
Pacific endodontids. Features of the apertural barriers
are identical to those found in the holotype.
Minidonta taravensis, new species (Solem & Cooke).
Figure 71a-c.
Diagnosis. — Shell larger than average, diameter 2.48-2.68 mm.
(mean 2.58 mm.), with 5%-55» normally coiled whorls. Spire and
apex distinctly and evenly elevated, last whorl descending a little
more rapidly, H/D ratio 0.546-0.556 (mean 0.551). Umbilicus
narrowly open, U-shaped, last whorl decoiling more rapidly,
contained 5.40-6.82 times (mean 6.11) in the diameter. Postnuclear
sculpture of narrow, prominent, protractive radial ribs, 64-72 (mean
68) on the body whorl, whose interstices are 3 - 5 times their width.
Microsculpture of rather prominent radial riblets, five to nine
between each pair of major ribs, and spiral riblets that are much less
than half the size of the radials. Sutures impressed, whorls strongly
rounded above and on umbilical margin, markedly compressed
laterally and basallv. Aperture elongately ovate, compressed later-
ally, inclined about 15° from shell axis. Parietal barriers 4, extending
more than one-quarter whorl: upper a very high, thin blade,
narrowly expanded and serrated above, sharply descending over
anterior fifth; 2nd much shorter and lower, deeply recessed,
relatively much more expanded and serrated above, with gradual
anterior descension; 3rd parietal low and threadlike, bifid with both
tops expanded and serrated after anterior fifth which is a merged
threadlike trace, with a thin bladelike lamella arising between the
two arms: 4th threadlike for anterior quarter, abruptly rising to a
very high lamellar posterior, broadly expanded and rolled above.
Columellar barrier a bladelike ridge displaced onto basal margin,
with a laterally extending crescentic blade located just below upper
edge. Palatal barriers 4, extending posteriorly beyond line of vision,
with broad, low accessory traces between columellar and 1st palatal,
1st and 2nd palatals, then 2nd and 3rd palatals, with only last one
prominent: 1st palatal greatly reduced in height, narrowly expanded
above, with very gradual anterior descension; 2nd very high, broadly
expanded above, with sharper anterior descension; 3rd situated
opposite 2nd parietal, equal in height to 2nd palatal, more expanded
above, with more gradual anterior descension; 4th reduced in height,
situated opposite 1st parietal, with abrupt anterior descension.
The bifid 3rd parietal and lateral accessory blade
on the columellar barrier immediately separate Mini-
donta taravensis from other species of Minidonta. It is
the only species in that genus with 4 parietals and
closely approaches the structure found in Anceyo-
donta.
Description. — Shell small, with 5% normally coiled whorls.
Spire and apex moderately and evenly elevated, last whorl
descending more rapidly. H/D ratio 0.556. Embryonic whorls 1%,
sculpture eroded. Remaining whorls with moderately wide, protrac-
tive radial ribs, 64 on the body whorl, whose interstices are 3-5 times
their width. Microsculpture of relatively prominent radial
riblets. crossed by much finer and more crowded spiral riblets.
Sutures moderately impressed, whorls rounded above, flattened
laterally and on the base. Umbilicus U-shaped, narrow, last whorl
decoiling more rapidly, contained 5.40 times in the diameter. Color
leached from shell. Aperture compressedly ovate, inclined about 15°
from shell axis. Apertural barriers as in diagnosis above. Height of
holotype 1.49 mm., diameter 2.68 mm.
Holotype. — Gambier Islands: Mangareva, Station
126, Taravai Islet. Collected in sand by D. Anderson
on June 1, 1934. BPBM 138884.
Range. — Known only from the type set.
Paratype. - BPBM 138884.
Remarks. — Despite considerable efforts to find
additional specimens, only the two examples are
known.
The bifid 3rd parietal and columellar barriers are
diagnostic, and prevent confusing Minidonta tara-
vensis with any other endodontid. This species is
nearest to Anceyodonta of any Minidonta and could
be classified in that genus without any great stretch-
ing of generic limits. The widely spaced ribbing,
FIG. 71. a-c, Minidonta taravensis, new species. Station 126, Taravai Islet, Mangareva, Gambier Islands. Holotype. BPBM 138884; d-f,
Minidonta extraria, new species. Station 197, Mangareva Islet, Mangareva, Gambier Islands. Holotype. BPBM 139008. Scale lines equal 1 mm.
Figures c and f greatly enlarged. Drawings by YK reproduced through the courtesy of Bernice P. Bishop Museum.
149
150
SOLEM: ENDODONTOID LAND SNAILS
number and length of apertural barriers, greatly
reduced 1st palatal, and prominent V-shaped upper
palatal all are characters typical of Anceyodonta and
absent or rarely present in Minidonta. The bifid
columellar and bifid 3rd parietal, shape of the
umbilicus, low spire, absence of secondary spiral
cording or a sulcus, limited number of inconspicuous
palatal traces and low spire lead me to consider
taravensis as a species of Minidonta that closely
approaches, but does not reach, the evolutionary level
of Anceyodonta.
Minidonta simulata, new species (Solem & Cooke).
Figure 70a-d.
Diagnosis. — Shell larger than average, diameter 2.43-2.86 mm.
(mean 2.72 mm.), with 434-5% rather tightly coiled whorls. Apex and
spire moderately and evenly elevated, last whorl descending only a
little more rapidly, H/D ratio 0.518-0.658 (mean 0.562). Umbilicus
very narrow internally, last whorl decoiling quite rapidly, contained
3.96-6.31 times (mean 4.85) in the diameter. Postnuclear whorls with
low, narrow, protractively sinuated radial ribs, 71-92 (mean 78.5) on
the body whorl, whose interstices are 2-4 times their width.
Microsculpture of fine radial riblets, four to eight between each pair
of major ribs, crossed by much finer and more crowded spiral riblets.
Sutures impressed, whorls strongly rounded above and on umbilical
margin, markedly compressed laterally and less so on basal margin.
Aperture ovate, compressed laterally, inclined about 10° from shell
axis. Parietal barriers 3, extending about three-sixteenths of a whorl:
upper a high thin blade, posterior third very weakly expanded and
serrated, with gradual descension until just before anterior end; 2nd
a raised threadlike ridge, posterior third to half expanded and
serrated, extending further anteriorly than upper parietal; 3rd same
as 2nd, often slightly lower with posterior portion shorter. Colu-
mellar wall without any barrier (75 per cent) or with a recessed
crescentic trace (25 per cent). Palatal barriers 4, often with one
accessory trace (32 per cent), rarely (4 per cent) with two; lower
palatal at baso-columellar angle, reduced in height, a low lamellar
ridge; 2nd much higher, with more gradual anterior descension; 3rd
still higher, with more gradual descension over anterior half; 4th a
low, V-shaped ridge, moderately recessed. Accessory trace normally
between 2nd and 3rd palatals, rarely a second one between 1st and
2nd.
The much smaller Minidonta taunensis is very
similar in appearance to M. simulata, but differs in
ribbing, umbilical width and details of barrier struc-
ture. The Tuamotu Mautodontha daedalea is much
more depressed and with finer ribbing, although very
similar in barrier pattern.
Description. — Shell small, with 4:i/< whorls that regularly
increase in size. Spire moderately and evenly elevated, last whorl
descending slightly more rapidly, H/D ratio 0.535. Embryonic whorls
1%, showing very faint traces of microradial and microspiral
sculpture. Remaining whorls with relatively narrow, protractively
sinuated radial ribs, 86 on the body whorl, whose interstices are 2-4
times their width. Microsculpture of extremely fine radial riblets
crossed by very fine spiral riblets. Sutures impressed, whorls strongly
rounded above, compressed laterally. Umbilicus narrow, U-shaped,
last whorl decoiling quite rapidly, contained 4.53 times in the
diameter. All color leached from shell. Aperture ovate, somewhat
compressed laterally, inclined about 10° from shell axis. Parietal
barriers 3, extending three-sixteenths of a whorl: upper a high
bladelike lamella with sharp anterior descension; 2nd a raised
threadlike ridge weakly elevated posteriorly; 3rd same as 2nd, with
posterior portion shorter. No columellar barrier. Palatal barriers 4,
extending a little more than one-eighth whorl: lower smaller than
2nd or 3rd, with rather sharp anterior descension; 2nd and 3rd
progressively higher, with more gradual anterior descension; 4th a
much lower, prominent V-shaped ridge, recessed within aperture.
Height of holotype 1.51 mm., diameter 2.83 mm.
Holotype. — Gambier Islands: Mangareva, Station
88, Aukena Islet, along trail near gap. Collected by
Donald Anderson and C. M. Cooke, Jr. on May 28,
1934. BPBM 138698.
Range. — Known from Aukena, Mangareva and
Agakauitai Islets, Mangareva Island, Gambier Islands.
Paratypes. — Same as list of material.
Material.— Mangareva: Aukena Islet (Stations 88,
102) near the gap (30 specimens, BPBM 9409, BPBM
138698, BPBM 138756); Mangareva Islet (Station 187)
north part of Rikitea on open ground (1 specimen,
BPBM 141662); Agakauitai Islet (Station 195) on
northwest side on sandy soil (1 specimen, BPBM
138895).
Remarks. — The columellar barrier, when present,
is a very small recessed tubercle on the columellar wall
and could be easily overlooked. The palatal trace,
when present, is an accessory denticle between palatals
2 and 3, about as high as the 1st palatal, but only
slightly longer than high.
Most specimens were collected on Aukena, but the
single individuals from Mangareva and Agakauitai
have the same apertural barriers and fall within the
range of size variation shown by the Aukena shells
(table LXIV).
In gerontic individuals, which reach an observed
maximum diameter of 3.52 mm., the apertural barriers
are greatly reduced, with the palatals represented only
by slight bumps on the aperture (fig. 70d). The single
unbroken gerontic individual is so much larger than
the other specimens examined that it has been
deliberately excluded from determining the average
size of adult shells.
The name simulata is taken from the resemblance
of this species to Mautodontha daedalea (Gould) from
Makatea. The greater elevation of spire, smaller size,
the stronger, more widely spaced costae and longer
apertural barriers of simulata readily serve to dis-
tinguish the two species.
Minidonta extraria, new species (Cooke & Solem).
Figure 71d-f.
Diagnosis. — Shell large, diameter 2.76-3.03 mm. (mean 2.90
mm.), with 5%-55/8 normally coiled whorls. Apex and spire slightly
and evenly elevated, last whorl descending slightly more rapidly,
H/D ratio 0.500-0.524 (mean 0.512). Umbilicus narrow, U-shaped,
last whorl decoiling a trifle more rapidly, contained 5.25-5.41 times
(mean 5.33) in the diameter. Sculpture of narrow, prominent,
protractively sinuated radial ribs, 67-75 (mean 71.3) on the body
whorl, whose interstices are 3 - 5 times their width. Microsculpture of
fine radial riblets, four to eight between each pair of major ribs,
crossed by very fine and crowded spiral riblets. Sutures impressed,
whorls strongly rounded above and on basal margin, compressed
laterally. Aperture ovate, compressed laterally, inclined about 10°
from shell axis. Parietal barriers 3, extending almost one-quarter
whorl, each split into minor threads on a broad ridge: upper with
SYSTEMATIC REVIEW
151
posterior quarter expanded and serrated, an upper thread raised for
posterior half, then split, with two or three lower threads; 2nd with
posterior quarter elevated and expanded, with three or four
accessory threads; 3rd as 2nd, with only two or three accessory
threads. Columellar barrier a very low, broad, inconspicuous recessed
ridge. Palatal barriers 4, bulbous above, extending about one-
sixteenth of a whorl: lower a short crescentic ridge, moderately
recessed, with gradual anterior descension; 2nd almost twice as high,
much longer, equally expanded, with more gradual anterior
descension; 3rd similar to 2nd, more expanded above; 4th a much
lower, slender, bladelike ridge, less expanded above. Very faint, broad
swellings located between major palatals (not shown in fig. 71d, f).
The extraordinary splitting of the parietal barriers
into several threadlike accessory ridges immediately
identifies Minidonta extraria. Its short swollen palatal
barriers are also markedly different from the long
barriers seen in species of similar size (M. taunensis
and M. taravensis). On the structure of the parietal
barriers alone, no species of endodontid can be
confused with M. extraria.
Description. — Shell small, with 5% relatively narrow whorls.
Apex and spire only slightly elevated, last whorl descending a trifle
more rapidly, H/D ratio 0.524. Embryonic whorls 1%, worn, only
faint traces of radial microsculpture remaining. Postnuclear whorls
with very narrow, nearly vertically sinuated radial ribs, 70 on the
body whorl, whose interstices are 3-4 times their width. Micro-
sculpture of numerous fine radial riblets crossed by barely
visible spiral riblets. Sutures moderately impressed, whorls strongly
rounded above, slightly flattened laterally and on the basal margin.
Color mainly leached from shell, faint irregular reddish markings
visible above periphery. Umbilicus almost U-shaped, last whorl
decoiling a trifle more rapidly, contained 5.25 times in the diameter.
Aperture ovate, flattened laterally, inclined about 10° from shell
axis. Parietal barriers 3, extending about one-quarter whorl: upper
split into five threads, the uppermost of which is also bifid, third
major thread bulbously expanded for posterior quarter with minute
serrations on top; middle and lower parietal barriers similarly split,
but middle with upper three threads united and becoming bulbously
expanded posteriorly; lower parietal with only the upper thread
bulbously expanded posteriorly. Columellar barrier a broad, low,
recessed ridge, slanted slightly downwards. Palatal barriers 4, less
than one-sixteenth whorl in length: middle two palatals high, very
bulbously expanded and strongly serrated above; lower palatal an
expanded threadlike ridge serrated above; upper palatal a relatively
narrow, crescent-shaped lamella only slightly expanded above
posteriorly. Height of holotype 1.45 mm., diameter 2.76 mm.
Holotype. — Gambier Islands: Mangareva, Station
197, Mangareva Islet, Northeast of Vaituatai Bay.
Collected by Donald Anderson and C. M. Cooke, Jr. on
June 9, 1934. BPBM 139008.
Range. — Found on Mangareva, Aukena and
Taravai Islets, Mangareva, Gambier Islands.
Paratypes. - BPBM 9668, BPBM 138885.
Material. — Mangareva: Mangareva Islet,
northeast (Station 197) of Vaituatai Bay (1 specimen,
BPBM 139008); Aukena Islet (1 specimen, BPBM
9668); Taravai Islet (Station 126) in sand (1 specimen,
BPBM 138885).
Remarks. — One specimen was found at each of
three localities on three different islets. In size and
shape Minidonta extraria is perhaps nearest to M.
simulata, but it differs not only in the apertural
barriers but also in the character of the ribbing. The
striking parietal dentition (fig. 71f) by itself serves to
separate M. extraria from all other known Pacific
Island charopids and endodontids. The splitting of the
parietals is approached only by Helenoconcha min-
utissima (Smith, 1892) from St. Helena, which has
only one or two accessory threads per barrier and the
barriers are much higher (E. A. Smith, 1892, pi. 21, fig.
9b).
Genus Mautodontha, new genus
Generalized Endodontidae with typical apical and micro-
sculpture (except in M. ceuthma and M. zimmermani), major
sculpture varying from extremely fine and crowded (M. borabo-
rensis, M. maupiensis, and M. imperforata) to greatly reduced (M.
zebrina), normally with 80-154 ribs on the body whorl. Apex flat to
markedly elevated, body whorl descending sharply and rounded or
laterally compressed (Garrettoconcha} or slightly descending with
markedly angulated periphery (Mautodontha, s.s.). Whorls usually
4%-5'/2, tightly coiled, only in M. maupiensis, M. consobrina, and M.
boraborensis increased in number. Umbilicus broadly to narrowly
(M. zimmermani, M. zebrina, M. rarotongensis) open, rarely
constricted (M. punctiperforata) or closed (M. imperforata). Parietal
barriers basically 4 in number, frequently 1 or more absent or split
into traces, many species with only 1 or 2 parietals. Columellar
barrier weak or absent. Palatals absent in M. aoraiensis, M.
consimilis, M. acuticosta, and M. unilamellata', reduced to 2 or 3 in
M. rarotongensis; normally 4 or 5 with (Garrettoconcha) or without
(Mautodontha, s.s.) one to several accessory traces. Terminal
genitalia differing from that of Australdonta only in lacking a fleshy
extension of the penis head into which the penial retractor merges.
Anatomy otherwise unknown.
Type species. — Helix daedalea Gould, 1846.
The almost complete absence of anatomical data
makes ordering of the species within this plastic and
geographically scattered complex difficult. Individual
species show incipient or marked similarities to such
divergent evolutionary levels as Libera, Nesodiscus,
Australdonta, and the Rapan radiation. Mauto-
dontha seems to be the modern remnant of the
group from which the above genera evolved. The
trends in shell form, sculpture, umbilical contours, and
barriers outlined below may involve parallelisms,
particularly in regard to the consimilis- acuticosta-
unilamellata group. Data from the shell alone is
insufficient to decide whether polyphyletic or
monophyletic derivation is indicated for such particu-
lar species sets.
The presently known Rarotonga, Austral and
Society Islands Mautodontha are undoubtedly extinct
(with the probable exceptions of the high altitude
Tahitian M. zimmermani and M. aoraiensis). Further
refinement of the classification will depend on collec-
tion of additional species from the remnant high forest
patches in the Society Islands, recovery of live
material of M. daedalea from one of the Tuamotu
atolls, or collection of M. rarotongensis on Atiu and
M. imperforata from Aitutaki.
Since this genus is a "base group" within the
Endodontidae and the name Thaumatodon usually
has been applied to its species, the anagram Mau-
todontha was considered an appropriate designation.
FIG. 72. a-c, Mautodontha (M.) boraborensis (Garrett). Borabora, Society Islands. Paratype. BPBM 3763; d-f, Mautodontha
(M.) ceuthma, new species. Station 589, at 900 ft. elevation, Raivavae, Austral Islands. Holotype. BPBM 146590. Scale lines equal 1
mm. (a-c, MM; d-f, SG).
152
SYSTEMATIC REVIEW
153
The type species, M. daedalea from the Tuamotu
Islands of Anaa, Makatea, and Niau, approximates
what I consider the basic pattern of Mautodontha: a
depressed shell with flat or barely elevated spire,
widely open U- to cup-shaped umbilicus with some-
what flattened sides, the umbilicus regularly decoiling,
prominent and numerous apertural barriers (reduced
somewhat in daedalea), often with an angulated
periphery, and well-developed ribbing. From this basic
form there have been several directions of divergence.
In M. boraborensis there is crowding of sculpture,
development of a high angulated periphery, a great
increase in size and whorl count (fig. 72a), tightening
of coiling, widening of the umbilicus, and moderate
recession of the palatal barriers. Further development
of these conchological trends, coupled with barrier
reduction and recession, is culminated in the Society
Island endemic genus Nesodiscus.
Two species, M. ceuthma and M. zimmermani,
tend toward the characteristics of Australdonta, but
the wider umbilicus with slightly flattened sides, very
large and greatly expanded apertural barriers, and
secondary microsculpture of spiral cords (rather than
grooves) are important reasons for not placing
ceuthma in Australdonta. The supraperipheral sulcus,
grossly enlarged barriers, and secondary spiral cording
are not found in any other Mautodontha, and M.
ceuthma stands as a quite isolated species. M.
zimmermani from Tahiti has an angulated periphery
and traces of the microspiral grooving typical of
Australdonta. It has, however, different anatomical
features (see below), quite large apertural barriers, and
the flattened umbilical sides found in Mautodontha.
In the distinct elevation of the spire and resultant
narrowing of the umbilicus, M. zimmermani departs
from most Australdonta and typical Mautodontha,
perhaps foreshadowing the more extensive shifts seen
in M. zebrina. M. aoraiensis is basically similar to the
species discussed above in form, umbilicus, and ribbing,
differing most obviously in its total lack of palatal
barriers, altered 2nd parietal and depressed spire. The
apparent small size probably results from the fact that
the only collection consists of apparently juvenile
shells. The weak secondary spiral cording in that
species is very similar to that found in M. ceuthma.
Despite its general structural differences and much
smaller size, M. aoraiensis can best be associated with
the M. daedalea complex.
A much more obvious change is shown by M.
zebrina from Rarotonga. Although larger, higher, and
with a narrower umbilicus than M. zimmermani, the
two species greatly overlap in measurements and have
nearly identical apertural barriers (zebrina usually
lacks a columellar). The body whorl of M. zebrina
lacks an angulation and the umbilical walls show no
trace of flattening. The most obvious difference lies in
the drastic reduction in major sculpture shown by M.
zebrina, a trend carried further in M. maupiensis and
M. imperforata.
The second major group within Mautodontha, the
subgenus Garrettoconcha, comprises another pattern
of specialization, characterized by lateral compression
of the body whorl, tighter whorl coiling, rapid
descension of the body whorl, narrowed umbilicus,
reduced to greatly reduced barriers usually with
accessory traces, and often very crowded or reduced
ribbing. The least differentiated species, M. consobrina
from Huahine, has a widely open umbilicus without
marked flattening of the sides, a flat spire with rather
sharp descension of the body whorl, distinct lateral
compression of the body whorl, crowded ribbing, and a
full complement of relatively low apertural barriers.
While showing a number of similarities to typical
Mautodontha, the totality of its features place it in
Garrettoconcha. The Borabora M. saintjohni has the
umbilicus slightly smaller, the spire slightly elevated,
the last whorl descending very rapidly, but otherwise
is a miniature replica of M. consobrina. M. maupiensis
from Maupiti, is basically similar to the first two, but
has greatly crowded sculpture, a much narrower
umbilicus and the barriers quite reduced in size. M.
consobrina, M. saintjohni, and M. maupiensis all
retain 4 parietals (although numbers 2 and 4 are
greatly reduced and shortened in M. maupiensis), and
usually 4 palatals plus several accessory traces.
The Aitutaki M. imperforata probably belongs
here, although altered in a number of ways. Its
umbilicus is completely closed by inward expansion of
the columellar region, the apertural barriers are very
long and rather prominent with the 2nd and 3rd
parietals reduced and several additional traces present.
The whorls are not laterally compressed and the apex
and spire are moderately and evenly elevated (these
may be secondary modifications associated with umbil-
ical closure). Although these changes produce a quite
distinctive appearance, I doubt that they are impor-
tant enough for other than specific recognition.
M. parvidens has the barriers reduced in height
and normally one or two parietals have been lost. The
umbilicus is slightly narrower than in M. consobrina
or M. saintjohni, but the H/D ratio is lower, probably
because there is less lateral flattening of the whorls.
The very similar M. subtilis differs most obviously in
having much more widely spaced sculpture on the
spire and early body whorl plus a narrower umbilicus,
but is otherwise structured as in M. parvidens. The
Moorean M. punctiperforata has the umbilicus quite
narrow and usually the parietal barriers are altered
with numerous accessory traces replacing the 3rd
parietal. Some specimens, however, have 3 parietals
and the barriers enlarged. These specimens have an
appearance intermediate between that of M. parvidens
and M. zimmermani in terms of barrier structure. M.
rarotongensis from Atui, Cook Islands has the same
parietal barriers as the above, but the upper palatals
are lost, the umbilicus is rather narrow with strongly
rounded sides, and there is significant lateral
compression of the body whorl.
154
SOLEM: ENDODONTOID LAND SNAILS
Finally, in M. consimilis, M. acuticosta, and M.
unilamellata the apertural barriers are reduced to only
1 or 2 parietals, with the palatals lost. The last two
species have wider umbilici and less compressed body
whorls than M. consimilis, thus somewhat approxi-
mating the form of M. zimmermani.
Geographically, Mautodontha is rather widely
dispersed. Single species are known from the Tuamotu
and Austral Islands, four species from the Cook
Islands (one each on Atiu and Aitutaki, two from
Rarotonga), with the remaining 11 species found in the
Society Islands. The replacement pattern of this
distribution in relation to the genus Minidonta has
been discussed above (p. 128).
Momentarily ignoring M. parvidens, which has
been collected on three islands (Borabora, Huahine
and Raiatea), Tahiti and Rarotonga each have two
species of Mautodontha. The Raiatean forms are
certainly monophyletic; the Huahine M. subtilis can
easily be derived from M. parvidens; and the Tahitian
M. zimmermani and M. aoraiensis probably share
common ancestry. This leaves only the Rarotongan M.
zebrina and M. unilamellata plus the Boraboran pair,
M. boraborensis and M. saintjohni, as representing
clear cases of separate faunal invasions of the same
island. Although showing slight differences between
different island populations (table LXVII), M. parvi-
dens presumably was a widely distributed lowland
species, native to Huahine, Tahiti, and Moorea, while
many of the others probably were found inland at high
or moderate elevations.
The only case of clear geographic relationship
concerns M. consobrina from Huahine, M. saintjohni
from Borabora, and M. maupiensis from Maupiti,
which are closely similar and allopatric.
Relationships of Mautodontha have been dis-
cussed above (pp. 113-114). Here it is sufficient to
emphasize that Australdonta differs in its peculiar
secondary microsculpture (fig. 124), large size, cari-
nated periphery with strong supraperipheral sulcus,
and narrower umbilicus with rounded internal mar-
gins; Minidonta by its internally constricted umbil-
icus, very small size, and often reduced apertural
barriers; Nesodiscus by its large size, many whorls,
umbilical brood chamber that may show membranous
closing, greatly reduced and usually deeply recessed
barriers, plus very crowded and reduced to lost
sculpture; Libera by its umbilical brood chamber and
much different shell shape.
KKY TO THE GENTS Mautodontha
1. Palatal barriers absent 2
Palatal barriers present 5
2. H/D ratio more than 0.400 3
H/D ratio less than 0.375.
Mautodontha (M. ) aoraiensis, new species
3. Mean diameter about 3.4-3.5 mm.; mean D/U ratio more than
4.00.
Mautodontha (Garrettoconcha) consimilis (Pease, 1868)
Mean diameter about 3.9-4.0 mm.; mean D/U ratio less than
3.75 4
4. Usually 2 or more parietal barriers; mean H/D ratio less than
0.500; Raiatea, Society Islands.
Mautodontha (Garrettoconcha) acuticosta (Garrett, 1884)
Only 1 major parietal barrier; mean H/D ratio about 0.550;
Rarotonga, Cook Islands.
Mautodontha (Garrettoconcha) unilamellata (Garrett, 1874)
5. Umbilicus at least slightly open 6
Umbilicus closed.
Mautodontha (Garrettoconcha) imperforata (Pease, 1870)
6. Mean D/U ratio less than 7.00 7
Mean D/U ratio more than 10.0.
Mautodontha (Garrettoconcha) punctiperforata (Garrett,
1884)
7. Body whorl without any supraperipheral sulcus 8
Body whorl with distinct supraperipheral sulcus; Raivavae,
Austral Islands Mautodontha (M.) ceuthma, new species
8. Mean diameter more than 3.6 mm. AND 4 parietal barriers
present 9
Mean diameter less than 3.6 mm. OR with only 3 parietal
barriers 10
9. Body whorl markedly angulated; Borabora, Society Islands.
Mautodontha (M.) boraborensis (Garrett, 1884)
Body whorl not angulated; Huahine, Society Islands.
Mautodontha (Garrettoconcha) consobrina (Garrett, 1884)
10. Mean D/U ratio more than 4.75 11
Mean D/U ratio usually much less than 4.75 13
11. Less than 100 ribs on body whorl; mean diameter more than 3.5
mm.; always 3 parietal barriers 12
More than 100 ribs on body whorl; mean diameter about 3.00
mm.; often only 2 parietals present.
Mautodontha (Garrettoconcha} rarotongensis (Pease, 1870)
12. Between 70-90 normal ribs on weakly angulated body whorl;
spire elevated; Tahiti, Society Islands.
Mautodontha (M. ) zimmermani, new species
Less than 45 reduced ribs on rounded body whorl; spire flat or
barely elevated; Rarotonga, Cook Islands.
Mautodontha (M.) zebrina (Garrett, 1874)
13. More than 100 ribs on body whorl in nongerontic specimens.. ..14
Less than 100 ribs on body whorl in nongerontic specimens.
Mautodontha (Garrettoconcha) subtilis (Garrett, 1884)
14. Less than 200 ribs on body whorl 15
More than 200 ribs on body whorl.
Mautodontha (Garrettoconcha) maupiensis (Garrett, 1872)
15. Mean H/D ratio 0.490 or greater 16
Mean H/D ratio about 0.425.
Mautodontha (M.) daedalea (Gould, 1846)
16. Palatal barriers 4, with four accessory traces; columellar barrier
present.
Mautodontha (Garrettoconcha) saint/ohni, new species
Palatal barriers usually 2 (rarely 3 or 4), no accessory traces;
columellar barrier absent.
Mautodontha (Garrettoconcha) parvidens (Pease, 1861)
Subgenus Mautodontha, s.s.
Rather depressed to flat-spired shells with a broadly open
umbilicus, the last whorl only slightly descending and the body
whorl at least weakly angulated. Apertural barriers prominent, large,
rarely with accessory traces, greatly reduced only in aoraiensis.
In narrowing of the umbilicus, both M. zimmer-
mani and M. zebrina somewhat resemble Garretto-
concha, but their remaining characters are those of
Mautodontha s.s. In its secondary sculpture, M.
zimmermani has the Australdonta pattern, while M.
ceuthma has the ribbing and supraperipheral sulcus of
that genus. In contrast, M. boraborensis presents a
10 1
u
£ -*
co|
_o
'+-*
rt
§
M
1
3:
n!
Q
0)
a:
O Ci T3
,_ 0) U
3 6 .5
J3 .^H r
C O C
S U rt
5 O, X
Z CO OJ
nj
00
00
I
o
c£
CM
CO
I
OO
a ?
5
Q
K
CO
CO
CO
CD
CN
^f
o
o
vO
•*'
c-
rH
(M*
c-
co
sr
e»
c-
rH
C3
O
CM
O
J3
CM CO
c~ ^ o
OO 00
to ^p o
co' co'
CO CD CO
1 1
1 1 1
IO -^
LO 0 (N
CD C-
tH CN CO
CN CO
^ LO CM
^f^ cn
CO 1C rH
rH C-
.-H 00 Oi
CO CO
lO VO CN
9
^ ^ ^-N
— .
t_ i
i-H iH 'x^.
CO OO
VO 10 ""*
1 ^^
1 1 •*
IO T-H
co -^ i
"+ IO
OO
^ ^ ra
Tf "* >X
CO
^—^ ^—^ I
+ +
10
IO IO "^
CD" o"
C? r7 C-"
OO 0
OO OJ IO
^t1 IO
•<* IO CO
0 O
0 O 0
1 1
IO C—
^ ^ CM
C- CO
CO C- ^f
CO •*
^f ^ CO
0 O
0 O 0
CS1 -^
VO D~
CN 00
IO O *ct*
^ IO CO
0 O
o o o
en co
c-" i? co~
IO O
en 10 ir-
co' co'
co ^ CM
1 1
O CO
IO IO O
00 00
CN C- CD
CM' <N°
CO CO <N
o' co"
rH^ C? OO
co en
CO rH CD
CO CM
Co" ^f' CM
oo '~>
c? c-" en"
CO
en ^ en
rH
rH (N* O
1 1 1
IO
CM rH Cn
rH
•^f 00 CO
i-H
rH rH CD
IO rH
Ln oo *f
CO ^P
co o en
rH rH
rH <N o'
C-
CD s-~.
s~ *. /^~^ ^~\
rH rH
O T-H CD
i en
en -^ co
rH '
co en
0 CM rH
rH 00
C- CO CO
t^ O^
cT oo" 55"
en
CO • •
IO
^ CO
rH
CO CD
CO CO
rH
rH
CM CD CO
T~t
•a;
c
m — «,
If i
13 1
CTj *— ' (U
-o o
p tJ -S
s s S s
So 2
w --- o
•^ N n)
155
156
SOLEM: ENDODONTOID LAND SNAILS
combination of characters that, when accentuated, are
typified by Nesodiscus.
Since only the two Tahitian species, M. zimmer-
mani and M. aoraiensis, have been dissected, close
phyletic association of these somewhat diverse species
from scattered localities can be questioned. Displaying
incipient or threshold stages toward the divergent
evolutionary levels represented by Australdonta and
Nesodiscus, unquestionably Mautodontha is a protean
group. Lacking comprehensive anatomical data, partic-
ularly in regard to M. boraborensis, M. ceuthma, and
the more generalized Nesodiscus (taneae and huahei-
nensis), it is best to resist a flat statement that both
Australdonta and Nesodiscus have been derived from
Mautodontha s.s. although this very probable hypo-
thesis is outlined above (p. 112).
The species do show a relatively coherent pattern
of structure (table LXV) and offer a distinct contrast
to Garrettoconcha (table LXVI). While very consid-
erable-to-complete overlap in range of any one charac-
ter exists because of parallel specializations, the
average dimension within each subgenus differs in four
of five basic parameters:—
Mean of: Ribs Height Diameter H/D ratio D/U ratio
Garrettoconcha 126.9 1.82 3.39 0.537 4.70
Mautodontha s.s. 102.7 1.55 3.51 0.441 3.89
While the diameters are essentially identical (only 3.5
per cent difference), Mautodontha s.s. has 19 per cent
fewer ribs, a 17.2 per cent wider umbilicus, 14.8 per
cent lower height and hence a 17.9 per cent less H/D
ratio. Except for the ribbing, these are obviously
correlated changes, but serve to emphasize the di-
chotomy of evolution within Mautodontha.
Mautodontha (M.) boraborensis (Garrett, 1884).
Figure 72a-c.
Pitys boraborensis Garrett, 1884, Jour. Acad. Nat. Sci., Phila-
delphia, 9, (1), pp. 32-33, pi. 2, figs. 18, a, b - Borabora, Society
Islands at 900 ft. elevation.
Helix (Enclodonta) boraborensis (Garrett), Tryon, 1887, Man.
Conchol.. (2). 3, p. 66, pi. 12, figs. 52-54.
Endodonta (Thaumatodon) boraborensis (Garrett), Pilsbry, 1893,
op. cit.. (2). 9. p. 26.
Diagnosis. — Shell very large, diameter 4.21-5.00 mm. (mean 4.54
mm.), with 6'/2-8 very tightly coiled whorls. Apex flat or barely
elevated, whorls of spire descending slightly, last whorl a little more
rapidly, H/D ratio 0.366-0.457 (mean 0.426). Umbilicus broadly V-
shaped, slightly and regularly dec-oiling, contained 2.09-2.98 times
(mean 2.49) in the diameter. Sculpture of narrow, very protractively
sinuated radial ribs, about 174-249 (mean 202) on the body whorl.
Sutures relatively shallow, whorls flattened above and below the
high and obtusely angulated periphery. Aperture subquadrangular,
inclined less than 10° from shell axis. Parietal barriers 4, extending
less than one-quarter whorl: upper a high bladelike ridge, posterior
third expanded and serrated above, with gradual anterior descension;
2nd and 3rd with anterior half to two-thirds threadlike, posterior
quarter to third as in 1st one; 4th parietal differing from 3rd only in
having posterior elevated portion lower and shorter. Columellar
barrier a recessed high ridge with gradual anterior descension,
slightly twisted downwards from plane of coiling at anterior. Palatal
barriers 4 (88.2 per cent) or 5 (11.8 per cent), extending about one-
eighth whorl: lower basal, a high crescentic lamella, slightly
flattened above with rather sharp anterior descension; 2nd, 3rd, and
4th (rarely) subperipheral, progressively lower and less crescentic
with more gradual anterior descension; upper located barely above
periphery, a lamellar ridge shorter than lower palatals and more
deeply recessed.
The very large size, numerous whorls, very widely
open umbilicus, and sharply angulated high periphery
easily separate M. boraborensis from the other Society
Island Mautodontha. The other large species, M.
acuticosta, lacks palatal barriers and has a much
narrower umbilicus. The smaller species of Nesodiscus
differ in having a raised apex with heavy, rounded
ribbing and at most only 2 parietals.
Description. — Shell very large, with 7W very tightly coiled
whorls. Apex and early whorls of spire flat, later whorls descending
gradually, last whorl moderately rapidly, H/D ratio 0.421. Apical
whorls I'/z, sculpture eroded. Postnuclear whorls with moderately
prominent, broadly rounded, very slightly protractively sinuated
radial ribs, 249 on the body whorl, whose interstices are about twice
their width. Microsculpture a lattice of fine radial riblets and
distinctly finer and a little more crowded spiral riblets. Sutures
moderately impressed. Whorls flatly rounded above with gently and
evenly rounded subperipheral margin. Periphery obtusely angulated,
strongly rounded; not protruded. Ground color light yellow horn
with irregularly spaced, narrow to broad, dark reddish-purple
flammulations. Umbilicus widely open, broadly V-shaped, regularly
decoiling, contained 2.38 times in the diameter with slight shoulder-
ing of whorl margins. Aperture subquadrangular, with flatly rounded
lower margin, inclined about 10° from shell axis. Parietal barriers 4,
extending three-sixteenths of a whorl: upper a high bladelike lamella
with very gradual anterior descension, broadened and flattened
above posteriorly; 2nd parietal with anterior half threadlike, slightly
lower and much narrower posteriorly; 3rd parietal, same as 2nd; 4th
parietal reduced to a threadlike trace, one-half length of upper.
Columellar barrier a prominent, low ridge, moderately recessed from
apertural margin, lying nearly parallel to plane of coiling. Palatal
barriers 4: lower 3 crescentic with gradual anterior descension,
moderately recessed and slightly flattened on top, extending about
one-eighth whorl, progressively reduced in height; upper palatal a
high, threadlike ridge, slightly longer than the lower barriers, located
just above periphery. Height of lectotype 2.11 mm., diameter 5.00
mm.
Lectotype. — Society Islands: Borabora at 900 ft.
elevation. Collected by Andrew Garrett. ANSP 47775.
Range. — Borabora, Society Islands at 800-900 ft.
elevation.
Paratypes. - BPBM 3763, ANSP 290091, Zurich.
Material. — Borabora: south slope Pahio-Temanu
ridge (Station 1093) at 800 ft. elevation in a cave
entrance (11 specimens, BPBM 152392-4); Borabora
(20 specimens, BPBM 3763, BPBM 170955, Zurich,
ANSP 290091).
Remarks. — In size and general appearance, M.
boraborensis is intermediate between the Society
Island Mautodontha and Nesodiscus. One specimen in
the Zoologisches Museum der Universitat Zurich, has
the same umbilical brood capsule that is characteristic
of Nesodiscus taneae and N. huaheinensis. The apical
sculpture of fine and widely spaced radials with finer
spirals combine with the large palatal barriers to place
this species in Mautodontha. Unfortunately, no pre-
served material was available.
SYSTEMATIC REVIEW
157
ab
FIG. 73. a-b, Mautodontha (M.) zebrina (Garrett). Rarotonga, Cook Islands. Paratype. BPBM 2337; c-d, Mautodontha (M.)
daedalea (Gould). 1 mile inland, Makatea, Tuamotu Islands. BPBM 115738. Scale lines equal 1 mm. Figures a-b (MM); c-d, by YK
reproduced through the courtesy of Bernice P. Bishop Museum.
Garrett (1884, p. 33) stated that this was
comparatively rare and found only at 900 ft. above sea
level. The only more recent collection, made by the
members of the Mangarevan Expedition in 1934, was
of dead specimens collected from debris in a cave
entrance at 800 ft. elevation.
Barrier variation was minimal, concerning only
the 4th parietal, which sometimes had the anterior
threadlike portion missing or the posterior part only
weakly elevated, and in the number of palatal barriers.
Usually, there were 3 subperipheral palatals and a
single supraperipheral ridge. Two specimens (of 17
adults) had a 4th subperipheral palatal and two
specimens had an accessory trace between palatals 2
and 3. Usually the supraperipheral palatal was
strongly elevated, but occasionally it was greatly
reduced in height.
Mautodontha (M.) daedalea (Gould, 1846). Fig-
ure 73c-d.
Helix (Pitys) daedalea Gould, 1846, Proc. Boston Soc. Nat. Hist.,
2, p. 173 - Matea ( = Makatea, Tuamotu Islands); Gould, 1846,
Exped. Shells, pp. 21-22 - Tahiti and Matea; Pfeiffer, 1848,
Monog. helic. viv., 1, p. 186 — Tahiti and Matea; Gould, 1852, U.
S. Explor. Exped., Wilkes, 12, pp. 54-55 — Aurora ( = Makatea)
and Tahiti; Gould, 1860, U. S. Explor. Exped., Wilkes, Atlas of
shells, pi. 4, figs. 51, a-d; Pfeiffer, 1868, Monog. helic. viv., 5, p.
221; Pfeiffer, 1876, op. cit., 7, p. 258; Johnson, 1964, U. S. Nat.
Mus. Bull., 239, p. 65.
Helix (Endodonta) daedalea (Gould), Tryon, 1887, Man. Conchol.,
(2), 3, p. 64, pi. 12, figs. 23-25.
Endodonta (Thaumatodon) daedalea (Gould), Pilsbry, 1893, op.
cit., (2), 9, p. 27.
Thaumatodon daedalea (Gould), Cooke, 1934, Occ. Pap. B. P.
Bishop Museum, 10, (11), p. 5 — Makatea.
Endodonta consobrina Aubert de la Rue and Soyer, 1958 (not
Garrett, 1887), Bull. Mus. Nat. d'Hist. Nat., Paris, 2nd ser., 30,
(4), p. 365 — Makatea, Tuamotu Islands (fossil).
Diagnosis. — Shell of less than average size, diameter 2.80-3.59
mm. (mean 3.20 mm.), with 5-6'/4 rather tightly coiled whorls. Apex
and early spire usually flat or slightly elevated, last whorl descending
slightly, H/D ratio 0.375-0.486 (mean 0.422). Umbilicus widely open,
cup-shaped, regularly decoiling, sides slightly flattened, contained
2.65-3.82 times (mean 3.14) in the diameter. Sculpture of low,
prominent, strongly protractively sinuated, rather closely set radial
ribs, 131-167 (mean 145.7) on the body whorl, whose interstices are
less than twice their width. Microsculpture of extremely fine and
crowded radial riblets, three to six between each pair of major ribs,
158
SOLEM: ENDODONTOID LAND SNAILS
crossed by slightly finer and more crowded spiral riblets. Sutures
impressed, whorls with evenly rounded margins, slightly compressed
laterally below periphery. Aperture elongate-ovate, laterally
compressed below rounded periphery, inclined about 20° from shell
axis. Parietal barriers 3 (67.7 per cent) or 4 (32.3 per cent), extending
about three-sixteenths of a whorl: upper with posterior third high
and bladelike, serrated and expanded above, with gradual descension
over anterior two-thirds; 2nd with posterior portion slightly shorter
and lower, anterior half threadlike; 3rd with posterior portion
distinctly reduced in height and length, anterior portion as in 2nd;
4th, when present, a threadlike trace, sometimes weakly elevated
posteriorly, often shortened. Columellar barrier absent, although
reduced lower palatal located at baso-columellar margin may be
mistaken for a columellar barrier. Palatal barriers 5, prominent,
extending about one-eighth whorl: lower at baso-columellar margin,
a short, slightly recessed, raised threadlike trace, quite inconspicuous
in most examples; 2nd a low bladelike lamella with rather sharp
anterior descension, reaching nearly to lip margin; 3rd a very high,
bladelike lamella whose edge points towards 2nd parietal, nearly
reaching lip margin, with very gradual anterior descension; 4th equal
in height to 3rd, narrower, longer, with more gradual anterior
descension; 5th palatal a moderately recessed, low, bladelike lamella,
shorter than 4th. Rarely TI additional palatal between 4th and 5th.
The very depressed shape, widely open umbilicus,
numerous ribs and presence of 5 or more palatal
barriers separate M. daedalea from the other Mau-
todontha. The only other species normally with 5
palatals, M. ceuthma from Raivavae, has much larger
barriers, a prominent supraperipheral sulcus, and only
about 90 widely spaced ribs on the body whorl.
Description. — Shell a badly broken adult with 5'« whorls
remaining, parietal hairier position indicating it originally had 5% +
whorls. Apex flat, spire slightly elevated, last whorl descending a
little more rapidly, H/D ratio 0.474. Apical whorls 1%, sculpture
obscured by glue. Remaining whorls with low, rounded, strongly
protractively sinuated radial ribs, 132 on the last remaining whorl,
whose interstices are less than twice their width. Microsculpture a
lattice of radial and slightly finer and more crowded spiral riblets.
Sutures impressed, whorls evenly rounded on outer margins,
compressed laterally below periphery. Umbilicus cup-shaped, regu-
larly decoiling, widely open, contained 3.39 times in the diameter.
Aperture not describable because of breakage. Color light yellow-
white with irregularly spaced, narrow to wide, zigzag reddish
flammulations. Parietal barriers 3, extending slightly less than three-
sixteenths of a whorl, with one low accessory trace; upper with
posterior third a very high lamella, anterior half a low lamellar ridge;
2nd parietal with posterior elevated portion shorter, anterior section
threadlike; 3rd parietal with posterior portion distinctly lower and
shorter, anterior portion identical. Accessory trace threadlike,
located between 2nd and 3rd parietals. Palatal wall completely
absent for first half whorl, so harriers not observed. Height of
remaining shell 1.48 mm., diameter 3.13 mm.
Lectotype. - Tuamotu Islands: Aurora (=Ma-
katea) Island. Collected by the United States Explor-
ing Expedition. MCZ 169115.
Range. - Makatea, Anaa, and Niau Islands,
Tuamotu Archipelago.
Material. -- MAKATEA (13 specimens, MCZ
169115, FMNH 46441, ANSP 1947, Paris): from 1 mile
inland at 250-300 ft. elevation (88 specimens,
BPBM 115738). ANAA: Tukuhoru Islet, under stones
and dead leaves (4 specimens, BPBM 136519). NIAU
(8 specimens, ANSP 156348, BPBM 118516).
Remarks. - The badly damaged lectotype is
obviously not the specimen figured by Gould (/or. cit.).
but is the only specimen surviving from the original
collection. It is well within the range of variation
shown by more recent collections.
In the original description, Gould mentioned 4
parietals, 5 palatals, and a small columellar nodule,
but in the first published illustration (Gould, 1860, pi.
4, figs. 51, a-d) there are only 4 palatals and no
columellar barrier shown. Only one of 32 adults
examined during this study had a weak columellar
trace, and no specimens had only 4 palatals. Since the
1st palatal is normally so small, it easily could have
been overlooked by the artist. In all other respects, the
figured specimen is typical of the species.
Barrier variation was moderate. Two-thirds of the
specimens had only 3 parietals, while most of the rest
had a small 4th barrier. Only in three examples was
there a 4th parietal equal in size to the others. One
individual had a 6th palatal present between the 4th
and 5th palatals. All others had the normal 5 barriers.
Material from Makatea collected in 1934 by the
Mangarevan Expedition and in 1955 by E. Aubert de
la Rue compared perfectly in respect to sculpture and
barrier configurations. Differences in H/D ratio (table
LXVII) are not significant (with 20 df, "t" = 0.1509),
while the difference in diameter is significant at the 5
per cent probability level ("t" = 1.7958). Although
statistically significant, there probably is no biological
meaning to this, since so many specimens were
damaged that exact separation of adult and subadult
examples was impossible. The Niau shells have
significantly narrower umbilici than the Makatea
specimens (with 17 df, "t" = 2.7036), but despite an
equivalent numerical gap (table LXVII), the difference
between the Niau and Anaa shells in umbilical width
is not statistically significant (with 6 df, "t" = 1.8800).
So few specimens from Niau and Anaa are involved
that the importance of these differences cannot be
evaluated.
The presence of M. daedalea on Anaa and Niau,
both of which are low coral atolls, is surprising and
should be investigated further. In view of the sig-
nificant differences in umbilical width, I hesitate to
state that "probably they were carried from Makatea"
by natives, yet they represent the only record of living
endodontids from atolls.
Mautodontha (M.) ceuthma, new species. Figure
72d-f.
Diagnosis. — Shell much smaller than average, diameter 2.83-
3.03 mm. (diameter 2.93 mm. I. with 5'-» relatively tightly coiled
whorls. Apex and spire moderately elevated, last whorl descending
slightly more rapidly, H/D ratio 0.467-0.500 (mean 0.484). Umbilicus
V-shaped, regularly decoiling, broadly open, contained 3.74-3.83
times (mean 3.791 in the diameter, sides flattened internally.
Sculpture of narrow, rather widely spaced, strongly protractively
sinuated radial ribs. 89-91 (mean 90) on the body whorl, whose
interstices are 2-4 times their width. Microsculpture of fine radials,
exceedingly fine spirals, and a secondary sculpture of low spiral cords
visible mainly above and below periphery. Sutures deep, whorls
SYSTEMATIC REVIEW
159
strongly rounded above, sloping down to prominent supra-
peripheral sulcus, periphery slightly angled, lower palatal margin
compressed and evenly rounded. Aperture ovate, upper palatal
margin concave, periphery angled, inclined about 25° from shell axis.
Parietal barriers 4, very high, extending one-quarter whorl, lower
greatly reduced in height with anterior threadlike portion absent.
Columellar barrier high, bladelike, serrated and expanded above,
with sharp anterior descension. Palatal barriers 5, extending one-
eighth whorl, with one weak lower accessory trace: 5th palatal much
lower, 4th palatal slightly lower than first 3 lamellae. For details of
tooth structure see description.
The very high, markedly serrated and expanded
barriers, distinct supraperipheral sulcus and weak
secondary spiral cording readily separate M. ceuthma
from all other Mautodontha. The presence of secon-
dary spiral cording rather than low spiral grooves
separates M. ceuthma from Australdonta. Only M.
daedalea normally has 5 palatals, but in that species
the barriers are much smaller, the ribbing much more
crowded and there is no supraperipheral sulcus.
Description. — Shell rather small, with 5% relatively tightly
coiled whorls. Apex and spire moderately elevated, last whorl
descending more rapidly, H/D ratio 0.500. Embryonic sculpture
eroded above, but visible in umbilicus as typical microradial and
microspiral ribbing. Remaining whorls with prominent, narrow,
rather widely spaced, strongly protractively sinuated radial ribs, 91
on the body whorl, whose interstices are 2-4 times their width.
Microsculpture of fine radial riblets, four to seven between each pair
of major ribs, crossed by very fine and crowded spiral riblets, with a
secondary sculpture of inconspicuous spiral cords. Sutures strongly
indented, whorls rounded on top, sloping down to marked suprape-
ripheral sulcus, followed by a slight peripheral angulation, evenly
rounded but compressed lower palatal wall and compressed umbilical
margin. Umbilicus V-shaped, widely open, regularly decoiling,
contained 3.74 times in the diameter, with a slight internal concavity
marking position of columellar barrier, side walls flattened. Color
uniform light reddish-brown. Aperture ovate with concave suprape-
ripheral margin, rounded and compressed lower palatal margin,
inclined about 25° from shell axis. Parietal barriers 4, extending one-
quarter whorl, teeth very high, upper an extremely high, thin
bladelike lamella, posterior third grossly expanded and serrated
above, middle third gradually descending, weakly expanded but not
serrated, anterior third a very gradually descending, low lamellar
ridge; 2nd with posterior quarter as in 1st, middle third descending
rather sharply, anterior portion a raised threadlike ridge; 3rd parietal
slightly lower than 2nd posteriorly, identical in shape; 4th parietal
identical in form, but greatly reduced in height with anterior
threadlike portion absent. Columellar barrier a high bladelike
lamella, strongly expanded and serrated above, with rather sharp
anterior descension, angling downward from plane of coiling. Palatal
barriers 5, extending one-eighth whorl, very high, with one weak
accessory trace: lower 2 palatals equal in size, higher than
columellar, identical in structure except more gradual anterior
descension; 3rd palatal distinctly higher than 2nd, identical in
structure, with more gradual anterior descension; 4th lower than
2nd, subperipheral, with very gradual anterior descension; 5th
palatal supraperipheral, located opposite bottom of sulcus, a low
lamellar ridge, expanded and serrated above, with very gradual
anterior descension. Height of holotype 1.41 mm., diameter 2.83 mm.
Holotype. — Austral Islands: Raivavae, Station
589, two-thirds way up cliff of Mt. Taraia at 900 ft.
elevation. Collected by Harold St. John, on a patch of
soil in a crevice out of the reach of goats on August 6,
1934. BPBM 146590.
Range. — Mt. Taraia, Raivavae, Austral Islands.
Paratypes. - BPBM 146569.
Material. — Raivavae: from foot to top of cliff of
Mt. Taraia (Stations 577, 589) up to 900 ft. elevation
(3 specimens, same as list of types).
Remarks. — The name ceuthma is taken from the
habitat of the type locality, a rock crevice safe from
the depradations of goats.
The general aspect of the shell is that of the
Austral Island genus Australdonta, from which it
differs in having secondary spiral ribbing instead of
grooves, very large parietal and palatal barriers instead
of their being relatively reduced in size, and the
umbilicus wider with rather flattened sides instead of
being narrower and with rounded sides. As indicated
above, classification of M. ceuthma into either Mau-
todontha or Australdonta could be justified utilizing
selected shell features. Despite the disjunct geography,
a preponderance of what I consider to be significant
characters support its inclusion in Mautodontha.
Mautodontha (M.) zimmermani, new species.
Figures 64c-d; 74a-c.
Diagnosis. — Shell slightly larger than average, diameter 3.25-
3.95 mm. (mean 3.61 mm.), with 4%-5l/4 loosely coiled whorls. Apex
and spire distinctly and evenly elevated, last whorl descending
slightly more rapidly, H/D ratio 0.434-0.483 (mean 0.455). Umbilicus
V-shaped, narrow, last whorl decoiling more rapidly, contained 4.15-
6.67 times (mean 5.13) in the diameter. Sculpture of fine,
protractively sinuated radial ribs, 70-90 (mean 80) on the body whorl,
with prominent periostracal extensions, whose interstices are 2-3
times their width. Microsculpture of very fine radial riblets, seven to
twelve between each pair of major ribs, barely visible spiral ribs, and
a secondary sculpture of weak irregular spiral grooves, prominent on
spire and near suture, absent near body whorl periphery. Aperture
ovate, strongly flattened above with gently rounded basal margin.
Periphery slightly, but distinctly, angulated. Parietal barriers 3,
extending about one-quarter whorl, lower greatly reduced in adults:
upper a high, bladelike lamella with posterior third to half expanded
and serrated, anterior half with very gradual descension; 2nd with
posterior third equal in height, anterior half threadlike; 3rd parietal
with posterior third greatly reduced in height, anterior threadlike
portion equal to 2nd in length or greatly shortened in older
individuals. Columellar wall with a deeply recessed, threadlike or
crescentic, short ridge. Palatal barriers 4, large, extending more than
one-eighth whorl: lower basal in position, a prominent, bladelike
ridge, moderately recessed, with gradual anterior descension, ex-
panded and serrated above; 2nd higher longer, with more gradual
anterior descension; 3rd equal in height to 2nd, usually more deeply
recessed, with much more gradual anterior descension; 4th suprape-
ripheral, equal in height to 1st or slightly lower, with same
descension as 2nd, deeply recessed.
The prominent radial ribs (70-90) on the body
whorl and angulated periphery are the main charac-
ters separating Mautodontha zimmermani from the
Cook Island M. z'ebrina. The relatively narrow
umbilicus, 3 parietals and weak secondary sculpture of
spiral grooves combine to separate it from any other
Mautodontha.
Description. - Shell large with 5'/4 relatively loosely coiled
whorls. Apex and spire evenly elevated, last whorl descending a little
more rapidly, H/D ratio 0.483. Embryonic whorls 1%, sculpture
eroded. Postnuclear whorls with relatively low and indistinct,
protractively sinuated radial ribs, about 90 on the body whorl, whose
interstices are about 2-3 times their width. Microsculpture of very
FIG. 74. a-c, Mautodontha (M.) zimmermani, new species. Station 865, Aorai trail at 5,600-6,300 ft. elevation, Tahiti, Society Islands.
Holotype. BPBM 145293; d-f. Mautodontha (M.) aoraiensis, new species. Station 870, west of Aorai trail at 5,000 ft. elevation, Tahiti, Society
Islands. Holotype. BPBM 145536. Scale lines equal 1 mm. (SG).
160
SYSTEMATIC REVIEW
161
fine radial riblets, extremely fine and crowded spiral riblets, plus
weak spiral grooves on spire and near sutures. Sutures deeply
impressed, whorls strongly rounded above suture, flattened laterally
above periphery and evenly rounded on basal margin. Periphery
weakly angulated. Umbilicus narrowly V-shaped, last whorl decoiling
much more rapidly, contained 6.67 times in the diameter. Color light
yellow horn with a few widely spaced, reddish flammulations on the
spire. Aperture ovate, flattened above periphery, somewhat
compressed below. Parietal barriers 3, extending three-sixteenths of a
whorl. Upper a high, bladelike lamella, posterior third expanded and
serrated above, with very gradual anterior descension; 2nd with
posterior third equal in height to 1st, anterior half threadlike; 3rd
with posterior third greatly reduced in height, anterior threadlike
portion ending well before anterior end of 2nd tooth. Columellar
barrier a very short crescentic ridge, deeply recessed within aperture.
Palatal barriers 4, extending about one-eighth whorl: lower a narrow,
bladelike lamellar ridge, slightly expanded and serrated above; 2nd
and 3rd progressively longer, higher and with more gradual anterior
descension; 4th palatal equal in height to 1st, deeply recessed, with
more gradual anterior descension, rather short. Height of holotype
1.91 mm., diameter 3.95 mm.
Holotype. — Society Islands: Tahiti, Station 865,
near top of Aorai Trail, ridge at 5,600-6,300 ft.
elevation. Collected by Elwood Zimmerman, Yoshio
Kondo, and Donald Anderson on September 15, 1934.
BPBM 145293.
Range. - Slopes of Mt. Aorai at 3,500-6,300 ft.
elevation, Tahiti, Society Islands.
Paratypes. — Same as list of materials.
Material. - Tahiti: Aorai Trail (Stations 860, 862,
863, 865, 867, 869) from 3,500-6,300 ft. elevation (12
specimens, BPBM 142071, BPBM 145119, BPBM
145165, BPBM 145225, BPBM 145293-5, BPBM
145491, BPBM 145701).
Remarks. — In possessing an angulated periphery
and weak spiral grooves, Mautodontha zimmermani
closely approaches Australdonta. The large apertural
barriers, internally constricted umbilicus, very weak
spiral sculpture, total lack of any supraperipheral
sulcus, simple penial pilaster pattern (fig. 64d), and
absence of a fleshy fusion of the penis with the penial
retractor (fig. 64c) combine to place zimmermani in
Mautodontha. The most similar species is the Rar-
otonga M. zebrina. Differences are outlined above in
the diagnosis.
Great pleasure is taken in naming this species
after Elwood Zimmerman, entomologist on the Man-
garevan Expedition, collector of many type specimens
described in this paper, and famous student of the
Pacific Island faunas.
Description of soft parts. — Only fragmentary animals were
available. Pallial region extending apically one-half whorl, flattened
length from pneumostome to base of kidney about 2.25 mm. Lung
roof clear, no granulation. Kidney about 0.69 mm. long and typical
in structure. Posterior third of kidney reaching hindgut. Ureter
typical, opening at point where kidney reaches hindgut. Heart partly
torn from surface of kidney and impossible to measure.
Apical genitalia not examined. Vas deferens (VD) entering
laterally near penis head, opening internally just beneath apical
fusion of penial pilasters (fig. 64d, PP). Penial retractor (PR)
inserting directly on penis head, no sign of any fleshy extension.
Penis (fig. 64c, P) slightly over 2 mm. long, tapering near atrial
junction. Internal sculpture of two longitudinal pilasters, fusing
apically above entrance of vas deferens, with one slightly twisted and
coiled just below midpoint of penis (fig. 64d). Union of free oviduct
and spermathecal stalk occurring just above entrance of penis and
vagina into the narrow atrium.
No satisfactory mount was obtained of either jaw or radula.
(Dissection based on BPBM 145293, one example previously
pulled from shell.)
Mautodontha (M.) zebrina (Garrett, 1874). Fig-
ure 73a-b.
Pitys zebrina Garrett, 1874, Proc. Acad. Nat. Sci., Philadelphia,
1873, pp. 234-235, pi. 3, fig. 66 - Rarotonga, Cook Islands;
Garrett, 1881, Jour. Acad. Nat. Sci., Philadelphia, 8, (4), p. 389.
Helix (Endodonta) zebrina (Garrett), Tryon, 1887, Man. Conchol.,
(2), 3, p. 64, pi. 12, figs. 17-19.
Endodonta (Thaumatodon) zebrina (Garrett), Pilsbry, 1893. op.
cit., (2), 9, p. 27.
Diagnosis. — Shell very large, diameter 3.75-4.57 mm. (mean 4.10
mm.), with 4 '4 - 5% quite loosely coiled whorls. Apex and early spire
flat or barely elevated, last whorl descending slightly more rapidly,
H/D ratio 0.474-0.540 (mean 0.507). Umbilicus constricted, V-shaped,
narrow, last whorl decoiling more rapidly, contained 5.20-6.44 times
(mean 5.85) in the diameter. Sculpture of very widely spaced,
protractive radial ribs, 32-41 (mean 34.8) on the body whorl, whose
interstices are 7-8 times their width, becoming greatly reduced to
indistinguishable on the body whorl. Microsculpture of prominent
radial riblets and extremely fine spiral riblets. Sutures impressed,
whorls smoothly rounded, slightly compressed above and below
periphery, umbilical margin strongly rounded. Aperture subcircular,
slightly flattened basally, inclined about 10° from shell axis. Parietal
barriers 3, lower greatly reduced, extending nearly one-quarter
whorl: upper a high lamellar ridge, posterior third with upper edge
weakly expanded and serrated, anterior part with very gradual
descension to just before end; 2nd with posterior quarter to third as
in 1st, anterior half threadlike; 3rd with elevated posterior portion
greatly reduced in height, shorter, anterior threadlike portion greatly
shortened to absent. Columellar wall usually without, rarely (16 per
cent) with a small, deeply recessed lamellar ridge. Palatal barriers
usually 4, rarely (16 per cent) with upper absent, extending one-
eighth whorl: lower basal, a raised, high lamellar ridge with gradual
anterior descension, moderately recessed; 2nd and 3rd progressively
higher, longer, with more gradual anterior descension; 4th suprape-
ripheral, a deeply recessed, short, threadlike or V-shaped trace,
sometimes absent.
The widely spaced, reduced radial sculpture,
constricted narrow umbilicus, large size, and large
palatal barriers diagnosis Mautodontha zebrina. The
other Cook Islands species of similar size, M. unilamel-
lata, has no palatal barriers, only one parietal barrier,
a widely open umbilicus and much more numerous
crowded ribs (table LXVI). M. zimmermani from
Tahiti is most similar in size and barrier structure, but
obviously differs in its regularly spaced radial ribbing
(70-90 on body whorl), angulated periphery and
elevated spire.
Description. — Shell relatively large, with 5% rather loosely
coiled whorls. Apex and spire slightly elevated, body whorl
descending a little more rapidly, H/D ratio 0.540. Apical whorls 1%,
sculpture eroded. Postnuclear whorls with low, widely spaced, radial
ribs, 41 on the body whorl, whose interstices are 7-8 times their
width, primarily indicated by long, periostracal extensions. Micro-
sculpture of prominent, lamellar, radial riblets, eight to twelve
between each pair of major ribs, with very fine, barely visible spiral
riblets. Sutures moderately impressed, whorls somewhat compressed
laterally above periphery and on basal margin. Color very light
yellow horn with irregular protractive, reddish flammulations that
162
SOLEM: ENDODONTOID LAND SNAILS
coalesce near periphery and tend to fade out near umbilicus.
Umbilicus narrowly open, internally constricted by whorl coiling,
contained 5.35 times in the diameter. Aperture subcircular, slightly
flattened basally and laterally above periphery, inclined about 10°
from shell axis. Parietal barriers 3, extending a little more than
three-sixteenths of a whorl: upper bladelike, with very gradual
anterior descension, posterior third weakly expanded and serrated on
top, anterior end sharply descending; 2nd with posterior third as in
1st, anterior half threadlike, total length equal to 1st; 3rd parietal a
reduced, threadlike ridge, only two-thirds length of upper, weakly
elevated posteriorly. Columellar wall with a deeply recessed, very
faint, rounded ridge, situated on moderately heavy callus. Palatal
barriers 4, extending about one-eighth whorl: lower a high, lamellar
ridge, recessed within aperture, with gradual anterior descension; 2nd
sub-crescentic, higher, with more gradual anterior descension, slightly
less deeply recessed; 3rd palatal a high, bladelike ridge, reaching
almost to apertural edge; upper palatal an indistinct threadlike ridge,
moderately recessed within aperture. Height of lectotype 2.47 mm.,
diameter 4.57 mm.
Lectotype. — Cook Islands: Rarotonga. Collected
by Andrew Garrett. ANSP 47799.
Range. — A valley on Rarotonga, Cook Islands.
Paratypes. - ANSP 290104, BPBM 2337.
Material. — Rarotonga (6 specimens, ANSP 47799,
ANSP 290104, BPBM 2337).
Remarks. - Garrett (1881, p. 389) reported that "a
half dozen specimens" were collected at the same place
as the otareae form of "Patula" decorticata, a
charopid belonging to an undescribed genus. No other
material is known. Surprisingly, all six of the original
specimens were located still preserved in museum
collections.
Other Cook Island species with apertural barriers
either belong to Libera, Thaumatodon, or have only a
single parietal and no palatal barriers (M. unilamel-
lata). Differences from the Tahitian M. zimmermani
are given in the diagnosis.
One specimen (the lectotype) had a distinct
columellar, and one individual had the 4th palatal
absent. Otherwise, the barrier structure was identical.
Mautodontha (M.) aoraiensis, new species. Fig-
ures 64e; 74d-f.
Diagnosis. - Shell very small, diameter 2.60-276 mm. (mean 2.68
mm.), with 4 -4'< normally coiled whorls. Apex and first
postnuclear whorl depressed, later whorls flatly coiled, last whorl not
descending more rapidly, H/D ratio 0.342-0.357 (mean 0.349).
Umbilicus broadly open, saucershaped, regularly decoiling, contained
2.82-3.00 times (mean 2.91) in the diameter. Postnuclear whorls with
high, prominent, protractively sinuated radial ribs, 61-66 (mean 63.5)
on the body whorl, whose interstices are 2-3 times their width.
Micros™ Ipture of six to nine very fine radial riblets between each
pair of major ribs and barely visible microspiral riblets, plus a very
weak sculpture of secondary spiral cords near the sutures and
umbilicus. Sutures deep, whorls strongly rounded above, compressed
laterally above and below rounded periphery, umbilical margin
strongly rounded. Aperture subcircular. compressed above and below
periphery, inclined about 15° from shell axis. Parietal wall with 2
barriers, extending three-sixteenths of a whorl: upper a high,
bladelike ridge, serrated on top, not expanded or raised posteriorly,
with smooth descension for anterior sixth; 2nd half the height of 1st,
with same shape and sculpture, differing only in more gradual
anterior descension. No columellar or palatal barriers.
The lack of any columellar and palatal barriers
separates Mautodontha aoraiensis from most species.
The very high parietal barriers, depressed spire, and
very wide umbilicus immediately separate it from M.
consimilis, M. acuticosta, and M. unilamellata, the
other Mautodontha that lack palatals. In these species
the parietal(s) is threadlike, the spire strongly elevated
and the umbilicus V- or U-shaped.
Description. — Shell relatively small, with 4'< loosely coiled
whorls. Apex and early spire slightly depressed, remaining spire
planulate, body whorl not decoiling more rapidly, H/D ratio 0.357.
Embryonic whorls l'/2, sculpture of two minor radial ribs between
each relatively large radial, with relatively closely spaced spiral ribs
about equal in size to the minor radials. Postnuclear whorls with
relatively high, protractively sinuated, lamellar radial ribs, 66 on the
body whorl, whose interstices are 2-3 times their basal width.
Microsculpture of six to nine low radial riblets between each major
rib pair, with barely visible spiral riblets plus weak secondary spiral
cords near umbilicus and sutures. Sutures moderately deep, whorls
strongly rounded above suture, compressed above obtusely angulated
periphery, evenly rounded and compressed below. Umbilicus widely
open, saucer-shaped, contained 3.00 times in the diameter. Color
light yellowish-white below with a slight reddish tinge above.
Aperture subcircular, compressed laterally above and below peri-
phery, inclined about 15° from shell axis. Parietal wall with 2 narrow
barriers, extending about three-sixteenths of a whorl: upper high and
bladelike, serrated on top, with rather sharp anterior descension,
otherwise the same in shape. No columellar or palatal barriers.
Height of holotype 0.99 mm., diameter 2.76 mm.
Holotype. - Society Islands: Tahiti, Station 870,
small valley west of Aorai Trail at 5,000 ft. elevation.
Collected by Donald Anderson on September 16, 1934.
BPBM 145536.
Range. - Near Aorai Trail at 4,700-5,500 ft.
elevation, Tahiti, Society Islands.
Paratypes. - BPBM 145536.
Material. - Tahiti: Aorai Trail (Stations 863, 870)
at 4,700-5,500 ft. elevation (3 specimens, BPBM
145536).
Remarks. — The three known specimens of
Mautodontha aoraiensis are subadult, but the numer-
ous differences from any other Society Island species
warrant their description as a new species. Despite the
many obvious differences in form and barriers, I expect
the M. zimmermani will be found to be the closest
relative. Additional young specimens may be mixed
with juveniles of Libera bursatella, which is sympat-
ric.
Description of soft parts. — One fragmentary example available.
Penis (fig. 64e, P) approximately 0.6 mm. long. Vas deferens (VD)
inserting laterally well below head of penis. No trace of penial
retractor left on specimen. Penis markedly tapering anteriorly,
becoming quite narrow near junction with atrium. Penis sculptured
internally with two longitudinal pilasters that merge above entrance
of vas deferens and extend as a single lobe into penis head. Shaft of
spermatheca and free oviduct joining just before union with penis to
form atrium. No other features of anatomy observed.
(Based on a partially extracted animal from BPBM 145536.)
Subgenus Garrettoconcha, new subgenus
Shell with normally elevated spire, narrower umbilicus than in
Mautodontha s.s., body whorl usually descending abruptly with the
<*!
Cxi 1
'
col
uo|
•*
COl
(J
CO
I
<N
xO|
CO
cpl
CO
CO I
IM
_g
co"
CD
co"
CO
•*
«
LO
O
O
rH
CO
LO
CM
co"
IT-
CO
0
rH
1
Q
1
1
i
1
1
(2
L—
rH
CO
CO
LO
LU
O
CM
c-
co
CN
CO
CO
D
CO
si
CO
O
CO
c£
s
co"
CN?
CO
Q
rH
3
uS
CM
of
u
CO
CV
5
CO
CO
CO
rH
CD
CO
CO*
"*
rH
rH
CO
"*
LO
*
CO
CO*
5
CO
0?
c7
CO
CN
rH
oo
LO
CO
rr-
LO
c?
LO
rH
IO
CD
LO
IO
LO
CO
i
LO
rH
1
00
CD
1
CN
CO
00
1
00
•**^
^*^
CJ
t^H
^^
CD
•N,
r_|
rH
TH
1O
LO
LO
1
O
VO
^
LO
^
tO
^
^
^
43
j.
^
^»*
jC
LO
V*
'T'
V
"^p"
CO
>^
5
OO
oo
tH
CN
^
CO
^J
OO
oo
CO
CO
rH
V
rH
CO
rH
CO
c-
iH
rH
rH
CO
LO
CO
LO
LO
IO
10
"*
LO
LO
LO
c?
^
C-
^
0?
^^
CO
co"
S"
(o
rH
C?
CO
OO
o
rH
LO
LO
CO
C-
LO
LO
CD
CO
CO
LO
LO
LO
CO
LO
CD
o
0
o
O
O
o
0
o
o
0
o
O
1
1
oo
LO
1
0
rH
1
CTJ
CO
1
en
CO
1
o
CO
1
oo
1
CO
CO
CM
1
CO
CM
1
CM
p
^p
LO
LO
LO
"*.
"*
l°-
^
"*.
•^
0
o
O
o"
0
0
o
0
o
o
o"
c^
00
CM
LO
C^
CO
LO
to
CO
LO
CN"
O3
LO
co'
o>
co"
rH
LO
oo
00
LO
co"
oo
LO
0
o"
0
0
o
0
O
o
0
0
O
s-*,
fi?
m
s?
u?
LO~
So
CD
\n
o~
So"
u
CO
o
CO
LO
o>
CO
CN
o
CM
£
if
co"
co"
CO*
co"
co"
co"
co"
•xt"
•*"
•*
<u
1
i
1
1
2
LO
LO
LO
CO
oo
CD
CO
rH
CN
CO
o
CO
ro
CO
r^
CO
o
CM
00
CD
co"
cxf
c£
co"
co"
cJ
CM
co"
co"
co"
co"
co"
CO
oo
c1^
0
CD"
CO
co"
cH"
rH
co"
rH
rH
0
co"
rH
O
CO
en
CO
co"
CO
co"
CO
co"
CO
CO
co"
•i
CO
s
co"
tr-
tr~
0
o~
CO
p
o
(ft
OO
oo
CO
E-
o
o"
CO
4J
rH
rH
rH
co'
CM"
CM"
TH
,H
CO
CM'
co"
JS
1
1
1
1
'S
00
c-
CD
CO
0
LO
c-
rH
OO
LO
CO
OO
00
CO
CO
c*
•
rH
0
tc
rH
rH
rH
rH
rH
rH
rH
TH
rH
rH
co"
sr
O
LO
o'
oo"
J^
ocT
CN"
^f
&
oo
LO
c-
o>
O
LO
CO
"9
0
cn
"~J
rH
rH*
rH
rH
CM
rH
rH
rH
CM*
rH
CM"
T3
0)
(U
5 P c
•° •-* 'c
cue
co"
.
CO
LO
CO
co
o
o
CM
O
co
d
CO
co
CO
co
CM
TH
CO
co
m
CO
c-
m
in
o
oo
OO
m
c-
00
00
c-
of
oo
T3
C
a)
O
3
"TJ oq
(0 S
M 1)
,2 E
3 o
0) 0)
Z co m
0
-O CO
a) C
^§
CN <~
163
TABLE LXVII. - LOCAL VARIATION IN MAUTODONTHA
Name
Number of
Specimens Height
Diameter
H/D Ratio
Whorls
D/U Ratio
boraborensis
BPBM 3763
11 1.94±0.045
4.
44±0.106
0.438±0.
0081
7 1/8-
2.60±0.063
BPBM 170955
(1.76-2.
19)
(3
.94-5.00)
(0.
411-0.
504)
(6 1/2-8)
(2.33-2.
98)
daedalea
Makatea
BPBM 115738
14 1.27±0.026
3.
09±0.04
0.412±0.
0064
5 1/4*
3.09±0.045
(1.15-1.
45)
(2
.80-3.36)
(0.
376-0.
452)
(5-5 1/2)
(2.65-3.
27)
Paris
8 1.44±0.050
3.
38±0.052
0.425±0.
0111
5 1/2+
3.01±0.073
(1.25-1.
68)
(3
.13-3.59)
(0.
375-0.
481)
(5 1/2-6 1/4)
(2.71-3.
31)
Niau
BPBM 118516
5 1.30*0.028
3.
05±0.046
0.426±O.OOU8
5 1/4
3.34*0.089
(1.22-1.
32)
(2
.90-3.13)
(0.
400-0.
455)
(5-5 3/8)
(3.16-3.
66)
Anaa
BPBM 136519
3 1.38±0.098
3.
27±0.154
0.421±0.
0110
5 1/4
3.03±0.156
(1.18-1.
51)
(2
.96-3.49)
(0.400-0.
434)
(5-5 1/2)
(2.77-3.
31)
zimmermani
4 1.65±0.221
3.
61±0.154
0.455iO.
012
5+
5.13±0.540
(1.41-1.
91)
(3
.22-3.95)
(0.
434-0.
483)
(4 3/4-5 1/4)
(4.15-6.
67)
zebrina
ANSP 47799
4 1.98±0.184
3.
92*0. 245
0.502±0.
016
4 3/4
6.16±0.270
(1.61-2.
47)
(3
.42-4.57)
(0.
471-0.
540)
(4 1/2-5 3/8)
(5.35-6.
50)
salntjohni
BPBM 152391
9 1.50±0.037
2.
84±0.041
0.528±0.
009
5 1/8
3.41±0.050
(1.36-1.
72)
(2
.65-3.05)
(0.
499-0.
580)
(4 7/8-5 5/8)
(3.17-3.
64)
maupiensis
BPBM 3358
4 1.85±0.063
3.
34±0.037
0.553±0.
016
6 1/4
4.55*0.480
(1.69-1.
99)
(3
.25-3.41)
(0.
510-0.
588)
(6-6 1/2)
(3.33-5.
42)
ANSP 47791
5 1.73±0.070
3.
09±0.084
0.555±0.
012
6 1/8-
3.90*0.107
(1.61-1.
95)
(2
.82-3.33)
(0.
521-0.
587)
(5 5/8-6 1/2)
(3.66-4.
29)
imperforata
BPBM
5 2. 09±0.055
3.
48±0.060
0.599±0.
007
5 3/4+
CLOSED
(1.95-2.
19)
(3
.31-3.64)
(0.
578-0.
617)
(5 1/2-6)
parvidens
Huahjne
28 1.52±0.030
3.
07±0.045
0.497±0.
006
5-
3.94*0.060
(1.18-1.
84)
(2.
40-3.49)
(0.
438-0.
558)
(4 1/8-5 1/4)
(3.46-4.
55)
Moorea
15 1.61±0.052
3.
27±0.070
0.492±0.
009
5 1/8 +
3.59*0.104
(1.25-2.
07)
(2
.86-3.95)
(0.430-0.
556)
4 5/8-5 3/4)
(3.09-4.
53)
subtilis
ANSP 47781
4 1.67*0.074
3.
13±0.087
0.534±0.
033
5 1/8-
4.53*0.170
(1.52-1.
85)
(2
.98-3.38)
(0.
511-0.
553)
(4 7/8-5 3/8)
(4.18-5.
00)
BPBM 2279
4 1.54±0.022
3.
13±0.067
0.492*0.
005
5-
4.34*0.235
BPBM 170889
(1.49-1.
59)
(2
. '.15-3. 25)
(0.
484-0.
505)
(4 3/4-5)
(3.92-4.
95)
consimilis
BPBM material
25 2.02±0.037
3.
40±0.044
0.594±0.
009
5 1/8-
4.59*0.152
(1.69-2.
38)
(3
.05-4.07)
(0.
530-0.
666)
(4 3/4-5 1/2)
(3.56-6.
25)
acuticosta
BPBM material
1.98*0.038
4.
06^0. 063
0.488±0.
008
5+
3.40*0.074
(1.66-2.
42)
(3
.44-4. 93)
(0.
423-0.
571)
(4 5/8-5 1/2)
(2.89-4.
27)
unllamellata
BPBM 2339
2.37*0.248
4.
19±0
.116
0.567±0.
075
5 1/4
3.76*0.339
(2.12-2.
62)
(4
.07-4.30)
(0.
492-0.
642)
(5 1/8-5 3/8)
(3.42-4.
10)
ANSP 47799
2.07±0.040
3.
81±0
.060
0.546±0.
019
5+
3.51*0.179
(2.02-2.
15)
(3
.71-3.94)
(0.513-0.
5SO)
(5-5 1/4)
(3.31-3.
86)
164
SYSTEMATIC REVIEW
165
periphery laterally compressed or evenly rounded (only rarely, M.
imperforata, weakly angulated). Apertural barriers reduced in size,
one or more parietals and palatals absent or split into fine accessory
traces.
Type species. — Helix parvidens Pease, 1861.
To a slight extent, Mautodontha consobrina and
M. saintjohni tend toward the basic form of Libera,
but I cannot say whether this has any direct phyletic
significance. They and their obvious direct derivative,
M. maupiensis, are most similar to Mautodontha,
s.s. M. punctiperforata, M. parvidens, M. subtilis,
and M. rarotongensis represent similar stages in
barrier reduction with various specializations in form
and sculpture (tables LXVI, LXVII). Probably M.
imperforata should be viewed as an extreme variant
within this grouping. Finally, M. consimilis, M.
acuticosta, and M. unilamellata have reached an
extreme stage of barrier reduction, are relatively large
in size, and have prominent, widely spaced sculpture,
whereas the other species tend to have crowded, very
fine sculpture.
The average differences from Mautodontha s.s. are
discussed above under that taxon. Unfortunately, no
anatomical material of Garrettoconcha was available.
Since the Mangarevan expedition of 1934 to Tahiti and
Borabora failed to collect any of Garrett's species — I
found no lowland endodontids in Tahiti during 1962
and 1974 collecting, and trips to Rarotonga in 1964
and 1965 failed to locate any endodontid species except
the supra-littoral Libera fratercula — I have little
doubt that Garrettoconcha is now extinct. The only
possible exceptions might be M. rarotongensis from
Atiu and M. imperforata from Aitutaki. A few
examples of the latter were collected by Peter Buck in
1929, but no subsequent attempt at collecting on that
island has been made.
Mautodontha (Garrettoconcha) consobrina (Gar-
rett, 1884). Figure 75d-e.
Pitys connobrina Garrett, 1884, Jour. Acad. Nat. Sci., Philadelphia,
9, (II, p. 31, pi. 2, figs. 17. a.b.c. — Huahine. Society Islands.
Helix (Endodonta) consobrina (Garrett). Try on, 1887. Man.
Conchol.. (2), 3, p. 66, pi. 12, figs. 43-45.
Endodonta (Thaumatodon) conxobrina (Garrett). Pilsbry, 1893.
op. at.. (2), 9, p. 26.
Diagnosis. - Shell rather large, diameter 3.55-4.31 mm. (mean
3.82 mm.), with 53/i-7'/4 rather tightly coiled whorls. Apex flattened
or slightly depressed, last whorl descending moderately, H/D ratio
0.458-0.532 (mean 0.497). Umbilicus broadly U-shaped, regularly
decoiling. contained 2.79-3.52 times (mean 3.10) in the diameter.
Sculpture of fine, vertical radial ribs, 141-164 (mean 153.3) on the
body whorl, whose interstices are about 2-4 times their width.
Microsculpture of four to seven fine radial riblets between each pair
of major ribs, crossed by barely visible spiral riblets. Sutures deep,
strongly rounded above and on umbilical margin, evenly rounded on
compressed outer margin. Aperture ovate, slightly compressed
laterally and on basal margin, parallel to shell axis. Parietal barriers
4, extending three-sixteenths of a whorl: upper high and bladelike.
posterior half serrated above, anterior half with very gradual
descension; 2nd and 3rd with posterior quarter to third higher than
1st, serrated and weakly expanded above, anterior half to five-
eighths threadlike; 4th with elevated posterior portion distinctly
lower and shorter, anterior threadlike portion inconspicuous or
partly absent. Columellar barrier a prominent raised ridge, rather
broad, lying parallel to plane of coiling, recessed, continuing
posteriorly beyond line of vision. Palatal barriers 4, prominent,
extending one-eighth whorl, with three to four accessory traces:
lower a short, bladelike lamella, expanded and serrated above,
moderately recessed, with posterior descension; 2nd palatal much
higher, longer, serrated on posterior half, gradually descending over
anterior half; 3rd palatal slightly lower with very gradual anterior
descension; 4th palatal supraperipheral, a moderately high threadlike
ridge, deeply recessed within aperture, shorter than 3rd. Palatal
traces located between palatals 1 and 2, 2 and 3. and 3 and 4,
occasionally above 4th.
Mautodontha saintjohni from Borabora has one
less whorl, is much smaller (mean diameter 2.84 mm.)
and has the elevated portion of the parietal barriers
much shorter. Otherwise the two species are very
similar. The high whorl count of M. consobrina at
once separates it from other Garrettoconcha, while the
presence of palatal traces and sharply descending body
whorl distinguish it from Mautodontha s.s.
Description. — Shell a little larger than average, with 5%
relatively tightly coiled whorls. Apex barely emergent, whorls of spire
gradually descending more rapidly, H/D ratio 0.532. Apical whorls
1:%, sculpture of rather widely spaced, narrow radial ribs with a
barely visible microsculpture between. Postnuclear whorls with
crowded, V-shaped, vertically sinuated radial ribs, 164 on the body
whorl, whose interstices are 2-3 times their width. Microsculpture of
fine radial riblets, crossed by very much finer and more crowded
spiral riblets. Sutures moderately impressed, whorls evenly rounded
on outer margin. Color light yellow horn with broad, frequent,
zigzag, reddish flammulations. Umbilicus narrow, U-shaped, regu-
larly decoiling, contained 3.52 times in the diameter. Aperture
subcrescentic with evenly rounded outer margin, nearly parallel to
shell axis. Parietal barriers 4, extending nearly one-quarter whorl:
upper parietal high, bladelike, with gradual anterior descension,
thickened and serrated above posteriorly; 2nd, 3rd, and 4th parietals
equal in height to 1st, but with medial, sharp descension to a
threadlike anterior portion which extends slightly further out of
aperture. Columellar barrier a low, broadly rounded, deeply recessed
ridge, extending beyond line of vision. Palatal barriers 4, extending
about one-eighth whorl: lower palatal basal in position, a lamellar
ridge moderately recessed within aperture; 2nd palatal a subcrescen-
tic lamella, flattened and broadly expanded above; 3rd palatal a
lamellar ridge with very gradual anterior descension; 4th palatal a
long, low, lamellar ridge with very gradual anterior descension.
Accessory traces located between 1st and 2nd, 2nd and 3rd, 3rd and
4th, and above 4th palatal barrier. Height of lectotype 1.91 mm.,
diameter 3.59 mm.
Lectotype. — Society Islands: Huahine. Collected
by Andrew Garrett. ANSP 47777.
Range. — "Peculiar to one valley," Huahine
Island, Society Islands.
Paratypes. - BPBM 2852, ANSP 290092.
Material. - Huahine (7 specimens, BPBM 2852,
ANSP 47777, ANSP 290092, SMF 165433).
Remarks. — It was reported by Garrett (1884, p.
31) as "rare and peculiar to one valley." No later
collections have been made.
The type is a small shell with somewhat unusual
apertural barriers. It was selected because other
members of the same set obviously were juvenile.
166
SOLEM: ENDODONTOID LAND SNAILS
Mautodontha (Garrettoconcha) saintjohni, new
species. Figure 75a-c.
Diagnosis. — Shell very small, diameter 2.64-3.03 mm. (mean
2.84 mm.), with 4%-5% moderately tightly coiled whorls. Apex and
spire flattened or barely elevated, spire descending slowly, last whorl
more rapidly, H/D ratio 0.494-0.584 (mean 0.528). Umbilicus U-
shaped, widely open, regularly decoiling, contained 3.17-3.64 times
(mean 3.41) in the diameter. Sculpture of narrow, low, prominent,
slightly protractively sinuated radial ribs, 109-136 (mean 123.3) on
the body whorl, whose interstices are about l'/2-2 times their width.
Microsculpture of very fine radial riblets, four to seven between each
pair of major ribs, crossed by distinctly finer and more crowded
spiral riblets. Sutures deep, whorls strongly rounded above and on
umbilical margin, with evenly rounded, very slightly compressed
outer margin. Aperture ovate, with evenly rounded outer margin,
inclined about 5° from the shell axis. Parietal barriers 4, extending a
little more than three-sixteenths of a whorl: upper high and
bladelike, posterior third serrated and weakly expanded above,
anterior half reduced in height; 2nd and 3rd with posterior third
equal to or slightly higher than 1st, anterior half threadlike,
extending beyond edge of 1st; 4th with posterior portion lower and
shorter, anterior threadlike section finer. Columellar barrier a deeply
recessed, very low crescentic ridge. Palatal barriers 4, extending a
little over one-eighth whorl, sometimes (22.2 per cent) with four
accessory traces: lower small, bladelike, expanded and serrated
above, with very gradual anterior descension; 2nd much higher and
longer, identical in shape; 3rd slightly lower, with even more gradual
descension, posterior expanded portion shorter; 4th a short, deeply
recessed, supraperipheral V-shaped ridge. Accessory traces, when
present, between palatals and above upper, all very short and
threadlike.
The much larger (mean diameter 3.82 mm.)
Mautodontha consobrina from Huahine has the same
apertural barrier pattern, but the elevated posterior
portion of the parietals is longer. In addition, M.
consobrina has one more whorl. M. maupiensis has the
2nd and 4th parietals reduced in size, much finer and
more crowded ribbing (over 200 ribs on the body
whorl) and a narrower umbilicus (mean D/U ratio
4.25).
Description. — Shell small, with 55/s rather tightly coiled whorls.
Apex and upper spire almost flat, lower whorls of spire descending
rapidly, H/D ratio 0.554. Embryonic whorls 1'4, sculpture of widely
spaced radial riblets crossing slightly lower and equally widely
spaced spiral ribs, producing a latticed effect, plus very fine radials
between the larger ones. Lower whorls with moderately prominent,
rounded, slightly protractively sinuated radial ribs. 136 on the body
whorl, whose interstices are l'/2-2 times their width. Sutures
moderately impressed, whorls strongly rounded above and in
umbilicus, evenly rounded on outer margin. Umbilicus U-shaped,
slightly and regularly decoiling. contained 3.42 times in the diameter.
Color white with prominent zigzag, reddish flammulations that
coalesce on base of shell. Aperture ovate, slightly compressed
laterally. Parietal barriers 4, extending three-sixteenths of a whorl:
upper parietal a high, bladelike lamella, serrated and weakly
expanded posteriorly, anterior half slightly lower in height, with
sharp descension at end; 2nd with posterior quarter equal in height
to 1st lamella, expanded and thickened above, anterior two-thirds a
threadlike ridge extending beyond anterior end of 1st parietal; 3rd
and 4th nearly identical to 2nd, except 4th with posterior section
slightly lower. Columellar barrier a deeply recessed, low crescentic
ridge, parallel to plane of coiling. Palatal barriers 4, extending
slightly more than one-eighth whorl: lower a low bladelike ridge,
slightly recessed, with gradual anterior descension, expanded and
serrated above; 2nd a high, bladelike lamella, with short flat
posterior portion and very gradual anterior descension; 3rd slightly
lower than 2nd, less expanded above, with very gradual anterior
descension; 4th supraperipheral, a short, deeply recessed, V-shaped
ridge. Height of holotype 1.71 mm., diameter 2.93 mm.
Holotype. — Society Islands: Borabora, Station
1093, south slope of Pahio-Temanu ridge at 800 ft.
elevation. Collected by Clifford Gessler and Harold St.
John on October 13, 1934. BPBM 152391.
Range. - Pahio-Temanu ridge at 800 ft. elevation,
Borabora, Society Islands.
Paratypes. - BPBM 152391.
Material. — Borabora (23 specimens, same as list
of types).
Remarks. — Unfortunately, no living specimens
were collected, although several of the shells were
quite fresh. About one-fifth of the shells had four
accessory palatal traces, the remaining shells had only
the 4 basic barriers. In the deepening of the umbilicus
and sharp descension of the body whorl, there is a
slight indication that both M. consobrina and M.
saintjohni foreshadow the structures typified by
Libera.
Great pleasure is taken in naming this species
after its collector, Harold St. John, botanist of the
Mangarevan Expedition.
Mautodontha (Garrettoconcha) maupiensis (Gar-
rett, 1872). Figure 76a-b.
Pitys maupiensis Garrett, 1872, Proc. Calif. Acad. Sci., 1872, p. 204
- Maupiti, Society Islands; Garrett, 1874, Proc. Acad. Nat. Sci.,
Philadelphia, 1873, pp. 233-234, pi. 3, fig. 64; Garrett, 1884, Jour.
Acad. Nat. Sci., Philadelphia, 9, (1), p. 31.
Patula maupitiensis Schmeltz, 1874, Cat. Mus. Godeffroy, 5, p. 93
— unnecessary emendation.
Helix maupitiensis (Garrett), Pfeiffer, 1876, Monog. helic. viv., 7,
p. 481.
Helix (Endodonta) maupitiensis (Garrett), Tryon, 1887, Man.
Conchol., (2), 3, p. 65, pi. 12, figs. 27-29.
Endodonta (Thaumatodon) maupiensis (Garrett), Pilsbry, 1893,
op. cit., (2), 9, p. 26.
Endodonta maupiensis (Garrett), Gude, 1913, Proc. Malacol. Soc.
London, 10, (5), p. 330 — Fiji Islands (erroneous record).
Diagnosis. — Shell much smaller than average, diameter 2.68-
3.39 mm. (mean 3.07 mm.), with 6-6'/2 relatively tightly coiled
whorls. Apex flat to slightly elevated, lower whorls descending much
more rapidly, H/D ratio 0.510-0.625 (mean 0.567). Umbilicus open,
U-shaped, barely decoiling, contained 3.33-5.42 times (mean 4.25) in
the diameter. Sculpture of extremely fine and crowded vertically
sinuated radial ribs, many more than 200 on the body whorl, whose
interstices are less than twice their width. Microsculpture of one or
two fine radial riblets between each pair of major radials crossed by
much finer and more crowded spirals. Sutures shallow, whorls evenly
rounded except for lateral compression below periphery. Aperture
ovate, compressed laterally, nearly parallel to shell axis. Parietal
barriers 4, 2nd and 4th reduced in height, anterior portion absent, 1st
and 3rd extending almost one-quarter whorl: upper a low lamellar
ridge with gradual descension over anterior half; 2nd deeply recessed,
lying along posterior third of upper, a higher lamellar blade with
gradual anterior descension; 3rd with posterior quarter having same
shape as 2nd parietal, anterior half a low threadlike ridge; 4th deeply
recessed as 2nd, usually a low rounded ridge, occasionally as high as
2nd. Columellar wall with deeply recessed, low crescentic ridge,
parallel to plane of coiling. Palatal wall with 4 moderately recessed
lamellar ridges, extending a little more than one-eighth whorl, plus
two to five (usually three), short, threadlike accessory traces: lower
at baso-columellar margin, a raised lamellar ridge to bladelike
barrier, slightly recessed, with gradual anterior descension; 2nd and
FIG. 75. a-c, Mautodontha (Garrettoconcha) saintjohni, new species. Station 1093, Borabora, Society Islands. Holotype. BPBM 152391;
d-e, Mautodontha (Garrettoconcha) consobrina (Garrett). Huahine, Society Islands. Paratype. BPBM 2852. Scale lines equal 1 mm. (MM).
167
168
SOLEM: ENDODONTOID LAND SNAILS
3rd higher, longer, more deeply recessed, with more gradual anterior
descension; 4th very slightly supraperipheral, a shorter, threadlike
ridge, quite deeply recessed. Accessory traces usually between 1st and
2nd, 2nd and 3rd, then 3rd and 4th palatals. Occasionally upper trace
absent, or additional traces above 4th palatal.
The extremely fine and crowded ribbing of
Mautodontha maupiensis is similar to the sculpture
found in M. imperforata from the Cook Islands which
differs in having a closed umbilicus and numerous
parietal traces. The very small Cook Island Minidonta
rotellina (diameter 1.96-2.19 mm.), differs in every
feature but sculpture. The most closely related taxa,
M. consobrina and M. saintjohni, do not have the 2nd
and 4th parietals reduced in size; both have much less
crowded sculpture.
Description. - Shell smaller than average, with slightly more
than 6'4 tightly coiled whorls. Apex barely emergent, first
postnuclear whorl flatly coiled, remaining whorls of spire gradually
descending more rapidly until spire has a distinctly conical
appearance, H/D ratio 0.587. Apical whorls 1%, sculpture of fine,
crowded radial riblets with a barely distinguishable microsculpture of
spiral and radial riblets. Postnuclear whorls with low, narrow, nearly
vertically sinuated, very crowded radial ribs, about 280 on the body
whorl, whose interstices are less than twice their width. Micro-
sculpture of an occasional radial riblet visible between the crowded
macroribs, with much finer spiral microribbing. Sutures moderately
impressed, whorls almost evenly rounded on outer margin, more
steeply rounded at shoulder and umbilicus. Color light yellow horn
with vague, somewhat regularly spaced, reddish flammulations.
Umbilicus narrowly U-shaped, barely derailing, contained 3.94 times
in the diameter. Aperture ovate, laterally compressed, evenly
rounded on outer margins, inclined about 5° from shell axis. Parietal
barriers 4, 2nd and 4th recessed: upper parietal long, bladelike,
extending nearly one-fourth whorl, posterior two-thirds serrated and
slightly expanded above; 2nd parietal with posterior one-third as in
1st, with sudden anterior descension to a threadlike appendage
reaching only to midpoint of 1st parietal; 3rd parietal identical in
shape to 2nd, but with threadlike anterior portion extending slightly
beyond anterior edge of 1st parietal; 4th parietal slightly reduced in
height, reaching only to midpoint of 3rd parietal. Columellar barrier
deeply recessed, moderately prominent, crescentic, lying parallel to
plane of coiling. Palatal barriers 4, with two accessory traces: 1st
palatal near baso-columellar margin, moderately prominent, blade-
like, extending one-eighth of a whorl; 2nd, 3rd, and 4th palatals
evenly spaced up to periphery, moderately recessed, low and
bladelike, extending slightly more than one-eighth whorl, 4th much
lower than 3rd. Accessory traces threadlike, short, located between
1st and 2nd, 2nd and 3rd palatals. Height of lectotype 1.83 mm.,
diameter 3.11 mm.
Lectotype. — Society Islands: Maupiti. Collected
by Andrew Garrett. ANSP 47791.
Range. — Maupiti Island.
Paratypes. - BPBM 3358, ANSP 290096.
Material. - Maupiti (21 specimens, BPBM 3358,
BPBM 170956, ANSP 47791, ANSP 290096, SMF
165728, Zurich).
Remarks. — Although Garrett stated that there
are only 2 or 3 parietal barriers, all specimens
examined proved to have 4. Since the barriers are low
and deeply recessed within the aperture, it is certain
that the lower one was overlooked. Although only 21
specimens could be located, this species apparently was
common on Maupiti Island. The subsequent record
from Fiji by Gude (see above), is almost certainly
based on a misidentification, although the specimens
on which this record was based could not be located. It
has been included above only for completeness of
literature citations.
An obvious derivative of M. consobrina, M.
maupiensis is somewhat intermediate to the M.
parvidens complex.
Mautodontha (Garrettoconcha) punctiperforata
(Garrett, 1884). Figure 76c-d.
Pitys punctiperforata Garrett, 1884, Jour. Acad. Nat. Sci.,
Philadelphia, 9, (1), p. 32, pi. 2, figs. 16a, b, c - Moorea, Society
Islands.
Helix (Endodonta) punctiperforata (Garrett), Tryon, 1887, Man.
Conchol., (2), 9, p. 66, pi. 12, figs. 49-51.
Endodonta (Thaumatodon) punctiperforata (Garrett), Pilsbry,
1893, op. cit., (2), 9, p. 26.
Diagnosis. — Shell slightly less than average in size, diameter
3.13-3.59 mm. (mean 3.36 mm.,) with 5'/2-57/8 normally coiled
whorls. Apex flat or slightly elevated, lower whorls descending much
more rapidly, H/D ratio 0.529-0.614 (mean 0.566). Umbilicus barely
perforate, constricted by expansion of the columellar region, last
whorl slightly decoiling, contained 8.50-14.3 times (mean 11.2) in the
diameter. Sculpture of numerous, slightly protractively sinuated
radial ribs, 136-143 (mean 139) on the body whorl, whose interstices
are about 2-3 times their width. Microsculpture of very fine radial
riblets, five to eight between each pair of major ribs, crossed
by much finer and more crowded spiral riblets that are barely visible
under 96 X magnification. Sutures deep, whorls strongly rounded
above, slightly compressed laterally above very weakly angled
periphery, with evenly rounded, laterally compressed lower palatal
and umbilical walls. Aperture elongate-ovate, with barely angled
periphery, inclined about 5° from shell axis. Parietal barriers 2,
extending about one-quarter whorl, with four to six accessory traces
or sometimes (28.6 per cent) 3 parietals, the lower greatly reduced:
upper high and bladelike, posterior half serrated and expanded
above, anterior third descending gradually; 2nd lower, posterior third
to half as in 1st, anterior half to third threadlike or a raised
threadlike ridge. Accessory traces below 2nd parietal, shorter than
parietals, often with an enlarged threadlike ridge in same position as
3rd parietal in related species. Columellar wall with a heavy callus
surmounted by a broad, blunt crescentic barrier, moderately
recessed within aperture. Palatal barriers 4, extending one-eighth
whorl, upper reduced in size: lower at baso-columellar margin, rarely
(14.3 per cent) shifted onto columellar wall, elongated and crescentic,
slightly recessed with sharp anterior descension; 2nd and 3rd high,
bladelike, longer, with progressively much more gradual anterior
descension, posterior half to two-thirds serrated and expanded above;
4th slightly supraperipheral, a threadlike to V-shaped ridge, shorter
and more deeply recessed than 3rd, sometimes absent. Accessory
traces very low, short, threadlike traces, located between palatals
and/or above 4th palatal.
The minute umbilicus at once separates Mau-
todontha punctiperforata from the other Society
Island species. The Cook Island M. imperforata has
much finer sculpture, a completely closed umbilicus,
and much lower and longer palatal barriers. The
minute (mean diameter 1.97 mm.) Minidonta rotellina
from Aitutaki, Cook Islands has very fine sculpture
and reduced palatal barriers.
Description. — Shell slightly smaller than average, with 5%
normally coiled whorls. Apex flat, whorls of spire gradually
descending more rapidly, H/D ratio 0.614. Apical whorls 1%,
FIG. 76. a-b, Mautodontha (Garrettoconcha) maupiensis (Garrett). Maupiti, Society Islands. Paratype. BPBM 3358; c-d,
Mautodontha (Garrettoconcha} punctiperforata (Garrett). Moorea, Society Islands. Paratype. BPBM 2857; e-f, Mautodontha
(Garrettoconcha) imperforata (Pease). Aitutake. Cook Islands. Lectotype. BPBM 2322. Scale line equals 1 mm. (MM).
169
170
SOLEM: ENDODONTOID LAND SNAILS
sculpture of narrow, crowded, radial ribs, microsculpture obscured.
Postnuclear whorls with high, rounded, prominent, slightly protrac-
tively sinuated radial ribs, 138 on the body whorl, whose interstices
are about twice their width. Microsculpture of relatively prominent
radial riblets, crossed by extremely fine and crowded spiral riblets.
Sutures moderately impressed, whorls strongly rounded on outer
margin, slightly compressed basally. Color light yellow horn with
prominent, reddish flammulations, broader above, becoming narro-
wer on the body whorl, fading out on base of shell. Umbilicus barely
perforate, constricted by extension of whorls, contained about 12.6
times in the diameter. Aperture subovate, slightly flattened basally,
inclined about 10° from shell axis. Parietal barriers 2, low, threadlike,
extending one-quarter whorl, with a faint, much shorter, lower trace.
Columellar wall with a heavy callus surmounted by two slightly
recessed threadlike ridges. Palatal barriers 2, low, threadlike,
moderately recessed within aperture, extending about one-eighth
whorl. Two accessory traces located between the barriers and several
faint traces located above upper palatal barrier. Height of lectotype
2.04 mm., diameter 3.33 mm.
Lectotype. — Society Islands: Moorea. Collected by
Andrew Garrett. ANSP 47780.
Range. — Moorea, Society Islands.
Paratypes. - BPBM 2857, ANSP 290094.
Material. — Moorea (10 specimens, BPBM 2857,
BPBM 116093, BPBM 170890, ANSP 47780, ANSP
290094).
Remarks. — The lectotype has slightly aberrant
apertural barriers, but was selected because of its good
preservation. Garrett (1884, p. 32) reported that a "few
examples were found" and that "one specimen is
uniform pale horn-color." The latter specimen was not
seen.
The angulation of the body whorl, great prolifer-
ation of secondary traces, height reduction of the
major barriers, and great constriction of the umbilicus
seem to be correlated changes that are carried much
further in the Cook Island M. imperforata. In that
species the umbilicus is closed, the major parietal
barriers have the elevated portions deeply recessed,
there are many more lamellar traces and extreme
flattening of the basal margin, but the peripheral
angulation is absent.
Mautodontha
(Pease, 1870).
(Garrettoconcha) imperforata
Figure 76e-f.
Pithys imperforata Pease, 1870. Jour, de Conchyl., 18, p. 394 —
Aitutaki, Cook Islands.
Pitys imperforata Pease, 1871, Proc. Zool. Soc. London, 1871, pp.
453, 474: Garrett, 1881, Jour. Acad. Nat. Sci., Philadelphia, 8,
(4). pp. 389-390.
Patula aitutakiana "Mousson" Schmeltz. 1874, Cat. Mus.
Godeffroy. 5, p. 94 — nude name.
Helix (Endodonta) imperforata (Pease), Tryon, 1887, Man.
Conchol., (2), 3, p. 68.
Endodonta (Thaumatodon) imperforata (Pease), Pilsbry, 1893, op.
cit.. (2), 9, p. 27.
Diagnosis. - Shell average in size, diameter 3.22-3.78 mm. (mean
3.43 mm.), with 5'/2-6V2 moderately tightly coiled whorls. Apex and
spire almost evenly elevated, slightly rounded above, last whorl
descending more rapidly, H/D ratio 0.539-0.658 (mean 0.592).
Umbilicus completely closed by expansion and reflection of
columellar lip. Sculpture of extremely fine, slightly protractively
sinuated radial ribs, more than 200 on the body whorl, whose
interstices are about equal to their width. Microsculpture of two to
four very fine radial riblets between each pair of major ribs, crossed
by much finer and more crowded spiral riblets. Sutures shallow,
whorls evenly rounded on outer margin, slightly compressed laterally
below periphery, basal margin flatly extended to umbilical callus.
Aperture elongately-ovate, laterally and basally compressed, inclined
about 10° from shell axis. Parietal barriers extending more than one-
quarter whorl, almost to or past limit of vision, 3 with elevated
portion and six to nine threadlike traces: upper high, thin, bladelike,
posterior two-thirds serrated and weakly expanded above, anterior
third gradually descending; 2nd with posterior eighth weakly
elevated, anterior three-quarters threadlike; 3rd with posterior eighth
slightly lower and shorter than 2nd, anterior part identical. Usually
two traces between 1st and 2nd parietals, one between 2nd and 3rd,
and four traces below 3rd parietal. All traces threadlike and stopping
well short of major parietals' anterior end. Columellar region covered
by very thick callus. Palatal barriers 4, long and bladelike, extending
nearly one-quarter whorl, with very short threadlike to crescentic
traces between major palatals near anterior margin, plus one or two
traces above 4th palatal: lower palatal reduced in height, hidden in
frontal view by edge of umbilical callus, identical in shape to 2nd
palatal; 2nd palatal prominent, bladelike, serrated and expanded
above, with very gradual anterior descension; 3rd and 4th palatals
equal in height and length to 2nd, with more gradual anterior
descension, 4th peripheral in position.
The closed umbilicus, heavy columellar callus, and
very fine sculpture immediately separate Mautodontha
imperforata from the other Society and Cook Islands
species. Only M. punctiperforata is apt to be confused,
and that species' less crowded sculpture and narrowly
open umbilicus are diagnostic differences.
L
Description. — Shell of average size, with 6 relatively loosely
coiled whorls. Apex and spire almost evenly elevated, slightly
rounded above, last whorl descending a little more rapidly, H/D
ratio 0.608. Apical whorls IVs, with slight traces of fine radial
sculpture remaining. Lower whorls with very fine, low, rounded,
indistinct, slightly protractively sinuated radial ribs, more than 225
on the body whorl, whose interstices are about equal to their width.
Microsculpture of fine radial riblets, two to three between each pair
of major ribs, and minute, crowded spiral ribs. Sutures shallow,
whorls somewhat flattened above, evenly rounded laterally and on
compressed basal margin, slanting gradually toward closed umbilicus.
Color yellowish-white with vague, irregular, reddish flammulations.
Aperture elongate-ovate with sharp baso-columellar prolongation,
inclined about 10° from shell axis. Columellar and inner basal walls
with thick strong callus, becoming weaker on palatal wall. Parietal
wall with 3 barriers and six traces extending posteriorly beyond line
of vision: upper very narrow, high, bladelike, serrated and very
slightly expanded above, with gradual anterior descension; 2nd with
raised lamellar posterior portion barely visible from aperture,
anterior segment threadlike; 3rd identical to 2nd, except elevated
posterior portion slightly lower. Accessory traces threadlike, stopping
short of major parietals' anterior end, located between 1st and 2nd,
between 2nd and 3rd, and four below 3rd parietal. No columellar
barrier. Palatal barriers 4, extending one-quarter whorl, upper
greatly reduced: lower an inconspicuous lamellar ridge hidden behind
columellar-basal callus in front view, serrated above with gradual
anterior descension; 2nd and 3rd high and bladelike, with very
gradual anterior descension; 4th a faint V-shaped peripheral ridge,
distinctly shorter than 3rd palatal. Height of lectotype 2.20 mm.,
diameter 3.52 mm.
Lectotype. — Cook Islands: Aitutaki. Collected by
Andrew Garrett. BPBM 2322.
Range. — Aitutaki, Cook Islands.
Paratypes. - BPBM 2322.
SYSTEMATIC REVIEW
171
Material. — Cook Islands (8 specimens, FMNH
117044, BPBM 167426, BPBM 170886): Aitutaki (14
specimens, BPBM 2322, BPBM 170938, BPBM
167425); inland of Reureu at 100 ft. elevation (6
specimens, BPBM 95647-8). "Rarotonga" (3 specimens,
SMF 165704).
Remarks. — In many specimens the lower palatal
barrier is hidden from casual view, but can be seen by
tilting the aperture. In most specimens the posterior
elevated portions of the 2nd and 3rd parietals can be
seen only by extreme tilting of the shell, since the
elevated portions sometimes do not start until just
before the limit of vision into the aperture.
The closure of the umbilicus and very heavy
columellar callus are quite different from the charac-
ters found in the other Cook and Society Islands
species.
Mautodontha (Garrettoconcha) parvidens (Pease,
1861). Figure 77a-b.
Helix parvidens Pease, 1861, Proc. Zool. Soc. London, 1861, p. 243
— Tahiti, Society Islands; Pfeiffer, 1868, Monog. helic. viv., 5, p.
220; Pfeiffer, 1876, op. cit., 7, p. 257.
Pitys parvidens (Pease), Garrett, 1884, Jour. Acad. Nat. Sci.,
Philadelphia, 9, (1), p. 31, pi. 2, figs. 14,a,6,c — Tahiti, Moorea,
Huahine, Society Islands.
Patula incerta "Mousson" Schmeltz, 1874, Cat. Mus. Godeffroy, 5,
p. 93 — nude name.
Endodonta incerta (Mousson), Binney, 1885, Ann. New York
Acad. Sci., 3, p. 88, pi. 2, fig. N — radula of Huahine Island
specimens.
Helix (Endodonta) parvidens (Pease), Tryon, 1887, Man.
Conchol., (2), 3, p. 64, pi. 12, figs. 20-22.
Endodonta (Thaumatodon) parvidens (Pease), Pilsbry, 1893, Man.
Conchol., (2), 9, p. 26.
Diagnosis. — Shell somewhat smaller than average, diameter
2.80-3.95 mm. (mean 3.19 mm.), with 4'/2 - 5% relatively loosely coiled
whorls. Apex and spire roundly elevated, last whorl descending a
little more rapidly, H/D ratio 0.430-0.558 (mean 0.496). Umbilicus
broadly U-shaped, often almost V-shaped, contained 3.09-4.55 times
(mean 3.81) in the diameter. Sculpture of very fine, closely spaced,
almost vertically sinuated, radial ribs, 104-180 (mean 138) on
pregerontic portion of body whorl, whose interstices are 2-3 times
their width. Microsculpture of two to five radial riblets between each
pair of major ribs, crossed by much finer and more crowded spiral
riblets. Sutures deep, whorls strongly rounded above and in
umbilicus, evenly rounded on outer margins. Aperture subcircular,
inclined about 5° from shell axis. Parietal barriers 2, rarely (7.1 per
cent) 3 or with 2nd fragmented into traces (4.8 per cent), extending
nearly one-quarter whorl: upper high and bladelike, posterior two-
thirds serrated and weakly expanded above, anterior segment
smooth, and sharply descending; 2nd distinctly lower, anterior third
often threadlike; accessory traces, when present, threadlike, very
crowded, equal in length to 2nd parietal. Columellar wall often with
1st palatal slightly elevated above baso-columellar margin. Palatal
barriers 4, rarely (14 per cent) 3 or 5, short, extending one-eighth
whorl: lower a very short, recessed, crescentic ridge at baso-
columellar margin or elevated on columellar wall, rarely absent; 2nd
high and bladelike, serrated above, nearly reaching lip margin, with
gradual anterior descension; 3rd equal in height to 2nd, slightly
longer, with more gradual anterior descension, nearly reaching lip
margin; 4th a short supraperipheral threadlike trace, rather deeply
recessed. Rarely (4.8 per cent) a 5th palatal present between numbers
1 and 2, accessory threadlike traces in a few examples.
Mautodontha subtilis from Huahine has a slightly
more open umbilicus, but differs most obviously in the
more widely spaced ribbing (fig. 77a, d), particularly on
the upper spire. The only other species normally with
only 2 parietals either lack palatal barriers or have a
much narrower umbilicus (M. rarotongensis).
Description. — Shell of average size, with 5W normally coiled
whorls. Apex and spire moderately elevated, slightly rounded above,
last whorl descending a little more rapidly, H/D ratio 0.525.
Embryonic whorls IVi, with only traces of microradial and
microspiral ribbing remaining. Lower whorls with quite closely
spaced, slightly protractively sinuated radial ribs, about 170 on the
body whorl, whose interstices are less than twice their width. On the
last quarter whorl, gerontic growth prevents accurate counting of the
ribs. Microsculpture of three or four fine radial riblets between each
pair of major ribs. Sutures deep, whorls strongly rounded above,
evenly rounded on outer margins. Umbilicus broadly U-shaped
(nearly V-shaped), regularly decoiling, contained 3.52 times in the
diameter. Color light yellowish-white with broad, protractively
sinuate, reddish flammulations becoming faint or absent on base of
shell. Aperture subcircular with flattened basal margin. Parietal
barriers 2, extending about three-sixteenths of a whorl: upper a
prominent lamellate ridge, posterior two-thirds serrated and weakly
expanded, anteriorly with sharp descension; lower a high threadlike
ridge for entire length. Palatal wall with 4 short barriers, extending
about one-eighth whorl: lower a broad, low ridge, slightly recessed, at
baso-columellar margin; 2nd and 3rd progressively narrower, much
higher, with more gradual anterior descension, more deeply recessed,
serrated above; upper reduced to a deeply recessed threadlike trace.
Height of lectotype 1.71 mm., diameter 3.26 mm.
Lectotype. — Society Islands: Tahiti. Collected by
Andrew Garrett. BPBM 170888 from the W. H. Pease
collection.
Range. — Tahiti, Moorea, and Huahine Islands.
Material. - Huahine (40 specimens, BPBM 3225,
BPBM 165092, FMNH 46598, FMNH 90620, SMF
165331, SMF 165735, ANSP 47793, ANSP 47758,
Zurich). Moorea (18 specimens, BPBM 15393, BPBM
165093, AMS). Tahiti (1 specimen, BPBM 170888).
Remarks. - Garrett (1884, p. 31) reported M.
parvidens as very common on Tahiti, Moorea and
Huahine Islands. He stated that specimens from
Huahine were slightly smaller and with a lighter
colored base than those from Tahiti and Moorea. No
specimens have been collected since Garrett's time,
and all observations must be based upon an analysis of
material in old collections. Only a single shell from
Tahiti was seen, while comparisons of the Moorea and
Huahine examples (table LXVII) showed that shells
from Huahine were significantly smaller in diameter
(with 41 df, "t" = 2.5039) and with a narrower
umbilicus ("t" = 3.1127).
Most specimens had only 2 parietal barriers, but
occasionally a 3rd one was present. Similarly, most
specimens had only 4 palatals, but occasionally an
additional palatal or several small traces are present.
Binney (1885, p. 88, pi. 2, fig. N) examined the radula
of Huahine specimens and reported (as Endodonta
incerta) that they had four laterals and seven
marginals in a half row.
Mautodontha (Garrettoconcha) subtilis (Garrett,
1884). Figure 77c-d.
• — * — I
x^Hp T4*"1"*"
^^^
WaiJHJffiiW^
. 1 ft -' *; ^'l .' .-I'.!. J
/-(' j: ' i 1
mu\'
\ v: \ >• V- \'
' V Y V %
'»• >• v '
V V. :
: 1: 1' :
h
c-f
-H
FIG. 77. a-b, Mautodontha (Garrettoconcha) parvidens (Pease). Tahiti, Society Islands. Lectotype. BPBM 170888; c-d,
Mautodontha (Garrettoconcha) subtilis (Garrett). Huahine, Society Islands. Paratype. BPBM 2279, e-f, Mautodontha
(Garrettoconcha) rarotongensis (Pease). Rarotonga (error), Cook Islands. Lectotype. BPBM 170885. Scale lines equal 1 mm. (MM).
172
SYSTEMATIC REVIEW
173
Pitys subtilis Garrett, 1884, Jour. Acad. Nat. Sci., Philadelphia, 9,
(1), pp. 31-32 - Huahine, Society Islands.
Helix (Endodonta) subtilis (Garrett), Tryon, 1887, Man. Conchol.,
(2), 3, p. 66, pi. 12, figs. 46-48.
Endodonta (Thaumatodon) subtilis (Garrett), Pilsbry, 1893, op.
cit., (2), 9, p. 27.
Diagnosis. — Shell of less than average size, diameter 2.94-3.38
ram. (mean 3.13 mm.), with 4%-5% normally coiled whorls. Apex
slightly elevated, lower whorls descending more rapidly, H/D ratio
0.484-0.553 (mean 0.513). Umbilicus U-shaped, slightly and regularly
decoiling, open, contained 3.92-5.00 times (mean 4.43) in the
diameter. Sculpture of narrow, rather widely spaced, vertically
sinuated radial ribs, 68-124 (mean of nongerontic shells 75.7) on the
body whorl, whose interstices are 3-5 times their width. Two gerontic
shells had 103 and 124 ribs, the rest 68-86. Microsculpture of fine
radial riblets, four to twelve between each pair of major ribs, crossed
by very much finer and more crowded spiral riblets. Sutures deep
whorls strongly rounded above and on umbilical margin, outer wall
evenly rounded. Aperture ovate, inclined less than 5° from shell axis.
Parietal barriers 2, extending about three-sixteenths of a whorl:
upper bladelike, posterior half to two-thirds expanded and serrated
above, with very gradual anterior descension; 2nd with posterior
third to half expanded and serrated above, but much lower, anterior
third to half threadlike, extending slightly beyond end of 1st parietal.
No columellar barrier, although 25 per cent of specimens have 1st
palatal moved up onto columellar wall. Palatal barriers 4, extending
about one-eighth whorl: lower at baso-columellar margin (75 per
cent) or on columellar wall (25 per cent), a slightly recessed, low
lamellar ridge; 2nd and 3rd progressively higher, longer, more deeply
recessed, with more gradual anterior descension; 4th supraperipheral,
a deeply recessed, low to raised threadlike ridge, slightly shorter than
3rd palatal.
The nearest relative to Mautodontha subtilis is M.
parvidens, which differs primarily in having much
more crowded sculpture (mean body whorl rib count
138).
Description. — Shell of average size, with 4% rather loosely
coiled whorls. Apex and spire evenly elevated, body whorl descending
a little more rapidly, H/D ratio 0.522. Apical whorls l'/2, sculpture of
fine, crowded, radial riblets, whose interstices are about IMs times
their width, with a microsculpture of co-equal radial and spiral
riblets. Postnuclear whorls with prominent, rounded, rather widely
spaced, vertically sinuated radial ribs, 68 on the body whorl, whose
interstices are 3-5 times their width. Microsculpture of fine radial
riblets, eight to twelve between each major rib, crossed by much
finer and more crowded spiral riblets. Sutures deep, whorls strongly
rounded above, with very slightly flattened basal margin. Color light
yellow horn with evenly spaced, wide, slightly zigzag, reddish
flammulations, fading out on base of shell. Umbilicus moderately
open, U-shaped, slightly decoiling, contained 4.18 times in the
diameter. Aperture ovate with strongly rounded margins, inclined
less than 5° from shell axis. Parietal barriers 2, extending slightly
more than three-sixteenths of a whorl: upper parietal high, bladelike,
with sharp anterior descension, posterior half rounded above with
fine, crystalline barbs; 2nd parietal slightly lower with more gradual
anterior descension, becoming threadlike near end. Palatal barriers 4,
extending one-eighth of a whorl: 1st a broadly rounded ridge located
at columellar-basal margin, moderately recessed on strong callus;
2nd and 3rd prominent, bladelike, with more gradual anterior
descension, slightly expanded and barbed above; 4th palatal lower,
less expanded, nearly threadlike. Height of lectotype 1.58 mm.,
diameter 3.03 mm.
Lectotype. — Society Islands: Huahine. Collected
by Andrew Garrett. ANSP 47781.
Range. — An unspecified valley on the north end
of Huahine, Society Islands.
Paratypes. - BPBM 2279, ANSP 290095.
Material. — Huahine (8 specimens, same as list of
types).
Remarks. - Garrett (1884, p. 32) reported that
this was a somewhat rare species, confined to a valley
on the north end of Huahine Island. No further
information is available.
In younger specimens, the difference in sculpture
between M. subtilis and M. parvidens is striking, but
in the older specimens of M. subtilis the distinction
becomes blurred because of gerontic growth. M.
parvidens has the sculpture crowded on the spire
whorls, while in M. subtilis, the sculpture is very
widely spaced on the spire, although usually crowded
on the body whorl. The lectotype is sub-adult, but is
by far the best preserved of the type set, clearly
showing details of the apical and microsculpture.
Possibly M. parvidens and M. subtilis are only
subspecifically distinct. Available material showed no
intergradation in sculpture and I prefer to accept
Garrett 's opinion that they are specifically distinct.
Mautodontha (Garrettoconcha) rarotongensis
(Pease, 1870). Figure 77e-f.
Pithys roratongensis (sic) Pease, 1870, Jour, de Conchyl., 18, pp.
395-3% - Rarotonga, Cook Islands (error).
Pitys roratongensis (sic) Pease, 1871, Proc. Zool. Soc. London,
1871, pp. 453, 474.
Helix (Pitys) roratongensis (sic) (Pease), Pfeiffer, 1876, Monog.
helic. viv., 7, p. 257.
Pitys rarotongensis Pease, Garrett, 1881, Jour. Acad. Nat. Sci.,
Philadelphia, 8, (4), p. 390 — Correction of Pease's misspelling of
the name and of the locality to Atiu, Cook Islands.
Helix (Endodonta) rarotongensis (Pease), Tryon, 1887, Man.
Conchol., (2), 3, p. 64.
Endodonta (Thaumatodon) rarotongensis (Pease), Pilsbry, 1893,
op. cit., (2), 9, p. 27.
Diagnosis. — Shell rather small, diameter 2.76-3.26 mm. (mean
3.01 mm.), with 41/2-51/4 relatively loosely coiled whorls. Apex
flattened, spire moderately elevated, last whorl descending more
rapidly, H/D ratio 0.464-0.556 (mean 0.522). Umbilicus U-shaped,
narrow, slightly decoiling, contained 4.67-6.00 times (mean 5.47) in
the diameter. Sculpture of narrow, relatively prominent, slightly
protractively sinuated radial ribs, 118-137 (mean 130) on the body
whorl, whose interstices are about twice their width. Microsculpture
of fine radial riblets, three to five between each pair of major ribs,
crossed by barely visible, crowded spiral riblets. Sutures impressed,
whorls strongly rounded above with slight lateral compression below
periphery. Aperture elongately-ovate, slightly compressed laterally
below periphery, inclined about 10° from shell axis. Parietal barriers
2 (36.4 per cent) or 3 (63.6 per cent), extending about one-quarter
whorl: upper high and bladelike, posterior half serrated and
expanded, anterior half with gradual descension to just before end;
2nd with posterior quarter to third equal in height to 1st, serrated
and expanded, anterior half to two-thirds threadlike, extending very
slightly beyond anterior end of 1st; 3rd, when present, a short
threadlike trace or V-shaped ridge lying along posterior half of 2nd
parietal. Columellar and palatal wall with thick heavy callus.
Columellar barrier deeply recessed, threadlike trace, angling slightly
downward from plane of coiling. Palatal barriers 2 (66.7 per cent) or
3 (33.3 per cent) extending about one-eighth whorl: lower a low
lamellar structure with gradual anterior descension; 2nd a distinctly
higher bladelike ridge, slightly less recessed, with more gradual
anterior descension; 3rd, when present, a short, weak, deeply recessed
supraperipheral threadlike trace.
174
SOLEM: ENDODONTOID LAND SNAILS
The presence of only 2 or 3 parietal and 2 or 3
palatal barriers effectively separates Mautodontha
rarotongensis from any species except M. parvidens.
The latter has a wider umbilicus, normally at least 4
palatals, and a more elevated spire.
Description. - Shell rather small, with 5 relatively loosely coiled
whorls. Apex flat, whorls of spire descending moderately, last whorl
more rapidly, H/D ratio 0.544. Embryonic whorls 1%, sculpture
eroded. Remaining whorls with relatively closely spaced, slightly
protractively sinuated, prominent radial ribs, about 130 on the body
whorl, whose interstices are less than twice their width. Micro-
sculpture of three to five fine radial riblets between each pair of
major ribs, crossed by barely visible spiral ribs. Sutures moderately
impressed, whorls rounded above and in umbilicus with slight basal
flattening. Umbilicus narrow, U-shaped, slightly decoiling, contained
6.00 times in the diameter. Aperture ovate, slightly flattened basally,
with moderately heavy columellar and palatal callus extending up
past periphery of body whorl. Parietal barriers 2, extending almost
one-quarter whorl: upper high and bladelike with very gradual
anterior and posterior descension; lower a threadlike ridge for entire
length. Columellar barrier reduced to a low swelling just posterior to
heavy columellar callus. Palatal barriers 2, extending about one-
eighth whorl, both moderately elevated, V-shaped ridges, lower
almost lamellar. Height of lectotype 1.61 mm., diameter 2.96 mm.
Lectotype. - Cook Islands. BPBM 170885, ex W.
H. Pease Collection.
Range. — Atiu, Cook Islands (on the authority of
Garrett).
Paratypes. - BPBM 2314, BPBM 170885, BPBM
170922.
Material. — Cook Islands (6 specimens, BPBM
170885, BPBM 170922); Rarotonga (3 specimens,
BPBM 2314); Atiu (3 specimens, BPBM 8545, SMF
165462).
Remarks. — Pease's original citation of Rar-
otonga as the locality was corrected to Atiu by
Garrett (1881, p. 390). Pease originally spelled the
specific name "roratongensis" which was also
corrected by Garrett (foe. cit.) to the proper rarotong-
ensis.
This would appear to be a derivative from a
parvidens type ancestor with a smaller umbilicus and
the palatal barriers reduced through expansion of the
apertural callus.
Mautodontha (Garrettoconcha) consimilis (Pease,
1868). Figure 78a-c.
Helix consimilis Pease, 1868, Amer. Jour. Conchol., 3, p. 227 —
Tahiti, Society Islands (error); Pfeiffer, 1876, Monog. helic. viv.,
7, p. 262.
Patula societatus "Mousson" Schmeltz, 1874, Cat. Mus.
Godeffroy, 4, p. 73 — nude name.
Patula consimilis (Pease), Schmeltz, 1874, op. cit., 5, p. 207;
Garrett, 1884, Jour. Acad. Nat. Sci., Philadelphia 9, (1), p. 29, pi.
2, figs. 12, a, b - Raiatea, Society Islands.
Helix (Endodonta) consimilis Pease, Tryon, 1887, Man. Conchol.,
(2), 3, p. 60, pi. 11, figs. 80-81.
Endodonta (Thaumatodon) consimilis (Pease), Pilsbry, 1893, op.
cit., (2), 9, p. 26.
Diagnosis. - Shell about average in size, diameter 3.03-4.05 mm.
(mean 3.43 mm.), with 45/s-5V8 rather tightly coiled whorls. Apex
flattened or barely elevated, whorls of spire descending moderately,
last whorl descending abruptly, H/D ratio 0.523-0.666 (mean 0.588).
Umbilicus U-shaped, usually regularly decoiling, rarely broadly V-
shaped, contained 3.56-6.19 times (mean 4.36) in the diameter. Body
whorl with slightly protractive radial ribs, 53-117 (mean 75.3) on the
body whorl, whose interstices are 3-4 times their width. Micro-
sculpture of very fine and crowded radial riblets, nine to fourteen
between each pair of major ribs, crossed by much finer and more
crowded spiral riblets. Sutures deep, whorls strongly rounded above,
with nearly evenly rounded or laterally compressed outer wall.
Aperture nearly circular, sometimes compressed on outer margin,
inclined about 5° from shell axis. Parietal barriers 1 (9.9 per cent) to
2 (90.1 per cent), extending about three-sixteenths of a whorl: upper
a raised threadlike ridge about twice as wide as high, situated well
above middle of parietal wall; 2nd, when present, a prominent to
very inconspicuous threadlike ridge. No columellar or palatal
barriers.
Mautodontha consimilis is apt to be confused with
both M. acuticosta and M. unilamellata. The former is
generally larger (mean diameter 4.01 mm.), more
depressed (mean H/D ratio 0.483), with a wider, V-
shaped umbilicus (mean D/U ratio 3.37), a greater
number of ribs on the body whorl (mean rib count
81.0), and more frequently lacks the 2nd parietal. M.
unilamellata is larger (mean diameter 3.96 mm.),
similar in shape (mean H/D ratio 0.554) and umbilical
width (mean D/U ratio 3.61), has more ribs on the
body whorl (mean rib count 82.0), a rounded periph-
ery, and usually lacks the 2nd parietal. The very small,
flat-spired M. aoraiensis is the only other Mau-
todontha without palatal barriers.
Description. — Shell average in size, with slightly more than 5
rather tightly coiled whorls. Apex and spire slightly and evenly
elevated, body whorl descending much more rapidly, H/D ratio
0.592. Apical whorls 1%, sculpture eroded on upper surface with
traces of prominent micro and major radial ribbing present in
sutures. Postnuclear whorls with prominent, narrowly rounded,
slightly protractive radial ribs, about 84 on the body whorl, whose
interstices are 2-4 times their width. Microsculpture of fine,
relatively crowded radial riblets crossed by much finer and more
crowded spiral riblets. Sutures deep, whorls somewhat shouldered
above, relatively compressed laterally with slightly flattened basal
margin. Color light yellowish horn with regularly spaced zigzag,
reddish flammulations, becoming less prominent on base of shell.
Umbilicus U-shaped, regularly and slightly decoiling, contained 4.29
times in the diameter. Aperture ovate, compressed laterally, basal
margin flattened, inclined less than 5° from shell axis. Parietal
barriers 2, extending almost one-quarter whorl, low and threadlike,
upper slightly more elevated and narrower. Columellar and basal lips
with a moderately heavy white callus, without trace of barriers.
Height of lectotype 2.01 mm., diameter 3.39 mm.
Lectotype. — Society Islands: Raiatea (erroneously
reported by Pease as Tahiti). Collected by Andrew
Garrett. BMNH 71.1.5.28 from the W. Harper Pease
collection.
Range. — Raiatea, Society Islands (originally
stated erroneously to come from Tahiti).
Paratype. - BMNH 71.1.5.28.
Material. - Raiatea (57 specimens, BPBM 3485,
BPBM 170891, Zurich, FMNH 46396, FMNH 90637,
FMNH 152017, ANSP 47786, ANSP 47784, ANSP
47787). Mislabelled material (24 specimens, BPBM
FIG. 78. a-c, Mautodontha (Garrettoconcha) consimilis (Pease). Raiatea, Society Islands. Paratype. BPBM 3485; d-e,
Mautodontha (Garrettoconcha) acuticosta (Garrett). Raiatea, Society Islands. Paratype. BPBM 3392; f-g, Mautodontha
(Garrettoconcha) unilameUata (Garrett). Rarotonga, Cook Islands. Paratype. BPBM 2339. Scale lines equal 1 mm. (d-g, MM; a-c,
SG).
175
176
SOLEM: ENDODONTOID LAND SNAILS
2.47 r
2.37 -
2.27
2.17
2.07
1.97
1.87
1.77
1.67
1.57
O
O
O
O
acuticosta
consimilis
3.15 3.35 3.55 3.75 3.95 4.15
Diameter in mm.
4.35
4.55
4.75
4.95
FIG. 79. Scatter diagram showing relationship of height to diameter in Mautodontha consimilis and M. acuticosta.
170891, BPBM 170895, FMNH 73186, FMNH 152020,
BMNH 71.1.5.28).
Remarks. — Garrett (1884, p. 29) reported this as
common and diffused throughout all the larger valleys
of Raiatea, and that Pease's type examples (reported
from Tahiti by Pease) were collected by him on
Raiatea. The type set in the British Museum (Natural
History) contained two specimens of Mautodontha
consimilis and three specimens of M. acuticosta.
Similar mixtures were seen in other old collections.
Presumably all such sets labeled "Tahiti" originated
through exchanges from Pease. The original descrip-
tion of M. consimilis perhaps better fits the form that
Garrett subsequently named M. acuticosta, but select-
ing a widely umbilicated shell for the type of M.
consimilis would have necessitated proposal of a new
name for the narrowly umbilicated species. I preferred
to avoid this and thus selected a narrowly umbilicated
shell for the type of Helix consimilis, leaving Patula
acuticosta Garrett, 1884, as the valid name for the
widely umbilicated species from Raiatea.
While the average differences between M. con-
similis and M. acuticosta are large (table LXVI), in
respect to any one character there is considerable
overlap. No specimen was seen that could not be
assigned to one or the other species without any
hesitation. Unfortunately, Garrett gave no indication
as to whether the species were geographically isolated
on Raiatea or found together. To test the hypothesis
that these might be selected examples from a
continuous range of variation, all measured individuals
were plotted in respect to height and diameter (fig. 79),
then for whorl count and diameter (fig. 80). The
division into two separate clusters is obvious. Calcu-
lation of linear regressions of the height-diameter
relationships for the two species by Bartlett's method
produced obviously divergent lines. I consider that M.
consimilis and M. acuticosta are distinct species.
Mautodontha (Garrettoconcha) acuticosta (Gar-
rett, 1884). Figure 78d-e.
Patula acuticosta "Mousson" Schmeltz, 1874, Cat. Mus.
Godeffroy, 5, p. 93 — nude name; Garrett, 1884, Jour. Acad. Nat.
Sci., Philadelphia, 9, (1), p. 30, pi. 2, figs. 13, a, b - Raiatea,
Society Islands.
Helix (Endodonta) acuticosta (Garrett), Tryon, 1887, Man.
Conchol., (2), 3, p. 60, pi. 11, figs. 60-61.
Endodonta (Thaumatodon) acuticosta (Garrett), Pilsbry, 1893, op.
cit., (2), 9, p. 26.
SYSTEMATIC REVIEW
177
5.75
5.50
5.25
5.00
4.75
4.50
o
00 00 00
o
o oooo
OOQSD 00
OGBSmXXD
o o
-o o <
o «
acuticosta
consimilis
j_
_L
_L
I
I
j_
3.15 3.35 3.55 3.75 3.95 4.15 4.35 4.55 4.75
Diameter in mm.
FIG. 80. Scatter diagram showing relationship of whorls to diameter in Mautodontha consimilis and M. acuticosta.
4-95
Diagnosis. — Shell large, diameter 3.42-4.90 mm. (mean 4.01
mm.), with 4% - 5% relatively loosely coiled whorls. Spire flattened
or barely elevated, later whorls descending more rapidly, occasion-
ally last whorls dropping sharply, H/D ratio 0.423-0.571 (mean
0.483). Umbilicus V-shaped (rarely U-shaped), widely open, decoiling
regularly, contained 2.89-4.27 times (mean 3.37) in the diameter.
Sculpture of relatively widely spaced, weakly protractive radial ribs,
59-106 (mean 80.95) on the body whorl, whose interstices are 3-5
times their width. Microsculpture of fine, radial riblets, seven to
eleven between each pair of major ribs, plus barely visible spiral
riblets. Sutures deep, whorls strongly rounded above, slightly
compressed laterally above and below rounded periphery. Aperture
subcircular, generally flattened laterally above periphery, inclined
about 5° from shell axis. Parietal barriers extending three-sixteenths
of a whorl, usually 1 (23.4 per cent) or 2 (63.9 per cent) rarely (10.6
per cent) with lower split into two traces, or very rarely (2.1 per
cent) with additional traces (four): upper a raised threadlike ridge
about twice as high as wide, serrated on top, with gradual anterior
descension, located well above middle of parietal wall; lower (when
present) an inconspicuous threadlike ridge equal in length to 1st
parietal. Accessory traces, one to four in number, identical in shape
and length to 2nd parietal. No columellar or palatal barriers present.
Mautodontha consimilis and M. unilamellata are
the most closely related species. M. consimilis is
distinctly smaller (mean diameter 3.43 mm.), more
elevated (mean H/D ratio 0.588), with a narrower
umbilicus (mean D/U ratio 4.36), fewer major radial
ribs (mean 73.3 on the body whorl), and only rarely
(9.1 per cent) lacks the 2nd parietal. M. unilamellata is
more elevated (mean H/D ratio 0.554) and usually has
only 1 parietal, sometimes with an accessory trace. M.
aoraiensis has 2 much larger parietals, a depressed
spire, and is much smaller (diameter 2.60-2.76 mm.).
Description. — Shell rather large, with slightly more than 5
moderately tightly coiled whorls. Apex and upper spire flat, lower
whorls descending gradually, H/D ratio 0.461. Apical whorls 1%,
sculpture mostly eroded, with traces of moderately closely spaced
radial ribs and a microsculpture of radial and spiral riblets persisting
in the suture. Postnuclear whorls with high, prominent, rounded,
almost vertically sinuated radial ribs, 86 on the body whorl, whose
interstices are 3-5 times their width. Microsculpture of fine,
crowded radial riblets crossed by very much finer and more crowded
spiral riblets. Sutures deep, whorls moderately shouldered above,
slightly compressed laterally both above and below rounded
periphery. Color light yellow horn without traces of darker markings.
Umbilicus V-shaped, regularly decoiling, contained 2.91 times in the
diameter, with slightly shouldered umbilical margin. Aperture sub-
circular, slightly compressed laterally above and below periphery,
inclined about 5° from shell axis. Parietal barriers 3, extending
slightly more than one-eighth whorl: upper high, bladelike, gradually
descending anteriorly, slightly flattened above with lower threadlike
bifid portion below: 2 lower parietals low and threadlike, extending
178
SOLEM: ENDODONTOID LAND SNAILS
slightly further anteriorly. Columellar and basal lips with moderately
heavy callus but no trace of barriers. Height of lectotype 1.94 mm.,
diameter 4.21 mm.
Lectotype. — Society Islands: Raiatea. Collected
by Andrew Garrett. ANSP 47774.
Range. — Raiatea.
Paratypes. - BPBM 3392, ANSP 290097.
Material. - Raiatea (28 specimens, BPBM 3392,
BPBM 115290, BPBM 165095, BPBM 170898, BPBM
170936, BPBM 170967, ANSP 47774, FMNH 46413,
FMNH 90623, FMNH 116996, FMNH 152019). Mis-
labelled material (30 specimens, BPBM 170891, BPBM
170895, BPBM 170903, FMNH 91090, FMNH 152018,
BMNH).
Remarks. - Garrett (1884, p. 30) reported that
this species was less abundant than M. consimilis, and
confined to Raiatea. Of some 58 shells, two were a
pure whitish horn color mutant that Garrett reported
as very rare.
The set of types in the Academy of Natural
Sciences Philadelphia consists of a juvenile, an albino,
and two adult specimens. One adult is aberrant in
having very few and widely separated ribs (64 on the
body whorl) while the other has the upper parietal
barrier bifid and the lower parietal split into two
traces. Despite the aberration of the parietals, the
specimen with more normal ribbing and form has been
selected as lectotype.
Of the 47 specimens for which the parietal barrier
number was recorded, 11 had 1 parietal; 30 had 2
parietals; 5 had the 2nd parietal split into two traces;
and one shell had a single parietal and four traces.
Mautodontha (Garrettoconcha) unilamellata (Gar-
rett, 1874) Figure 78f-g.
Pitys unilamellata Garrett, 1874, Proc. Acad. Nat. Sci., Phila-
delphia, 1873, p. 234, pi. 3, fig. 67 - Rarotonga, Cook Islands.
Patula unilamellata (Garrett), Garrett, 1881, Jour. Acad. Nat. Sci.,
Philadelphia, 8, (4), p. 388.
Helix (Endodonta} unilamellata (Garrett), Tryon, 1887, Man.
Conchol., (2), 3, p. 60, pi. 11, figs. 74-76.
Endodonta (Thaumatodon) unilamellata (Garrett), Pilsbry, 1893,
op. cit., (2), 9, p. 27.
Diagnosis. — Shell rather large, diameter 3.68-4.28 mm. (mean
3.96 mm.), with 5-5% normally coiled whorls. Apex moderately,
spire strongly elevated, last whorl descending much more rapidly,
H/D ratio 0.492-0.642 (mean 0.554). Umbilicus U- to V-shaped,
regularly decoiling, rather widely open, contained 3.31-4.10 times
(mean 3.61) in the diameter. Postnuclear whorls with prominent,
slightly protractively sinuated radial ribs, 78-87 (mean 82) on the
body whorl (149 in one gerontic shell), whose interstices are 2-3
times their width. Sutures deep, whorls strongly rounded above,
flattened laterally, with slightly compressed basal margin, umbilical
margin strongly rounded. Aperture subcircular, flattened laterally
above periphery, inclined about 10° from shell axis. Parietal wall
with single raised, threadlike barrier, extending less than three-
sixteenths of a whorl, often (40 per cent) with a vague lower
accessory trace present. No columellar or palatal barriers.
The open, regularly decoiling umbilicus, single
parietal and absence of any palatal barriers at once
separates Mautodontha unilamellata from the other
Cook Island species. It is very similar to the Raiatean
M. consimilis and M. acuticosta, differing most
obviously in having the single parietal barrier and high
spire.
Description. — Shell relatively large, with 5'4 rather loosely
coiled whorls. Apex moderately elevated, whorls of spire descending
gradually more rapidly, H/D ratio 0.513. Apical whorls 1%, sculpture
eroded with traces of fine radial ribbing remaining in the suture.
Postnuclear whorls with high, rounded, rather prominent, somewhat
protractively sinuated radial ribs, 149 on the body whorl, whose
interstices are 2-3 times their width. Microsculpture of very fine
radial riblets crossed by much finer and more crowded spiral riblets.
Sutures deep, whorls strongly rounded above, slightly compressed
laterally and on basal margin. Color light yellow horn with
numerous, crowded zigzag, reddish flammulations. Umbilicus widely
open, V-shaped, regularly decoiling, contained 3.31 times in the
diameter. Aperture ovate, slightly compressed laterally and on basal
margin, inclined about 15° from shell axis. Parietal wall with single,
supramedial, threadlike barrier extending three-sixteenths of whorl,
and a very faint, short, medial threadlike trace. Columellar and
palatal walls without barriers. Height of lectotype 2.01 mm.,
diameter 3.91 mm.
Lectotype. — Cook Islands: Rarotonga. Collected
by Andrew Garrett. ANSP 47798.
Range. — In mountain ravines on Rarotonga,
Cook Islands.
Paratypes. - BPBM 2339, ANSP 290110.
Material. — Rarotonga (5 specimens, same as type
material).
Remarks. — Garrett (1874, p. 235) stated this was
"A rare species found under decayed vegetation in
mountain ravines." The few known specimens exhibit
considerable variation in sculpturing. Four of the five
have 78-87 rather widely spaced ribs on the body
whorl, but the type has much more crowded and
numerous ribbing (149 ribs on the body whorl).
Probably this species occurred in more than one place,
and the ribbing types may have belonged to geographi-
cally separated populations.
Genus Anceyodonta, new genus
Generally large (except A. ganhutuensis, A. subconica, A.
constricta, and probably A. alternata) and specialized Endodontidae
in which the usually 4 parietal barriers extend at least one-quarter
whorl, the V-shaped upper palatal lies opposite the upper parietal,
there are normally four or more palatal traces, the mean H/D ratio
is over 0.600, the umbilicus is contained more than 7 times in the
diameter, and secondary spiral cording is present in most of the
specimens. Except in the very small species, there are, on the
average, more than 55/s whorls. Generally the ribbing is quite widely
spaced, with fewer than 9 ribs per mm. Many species have the
columellar barrier slanting downward or displaced onto the basal lip.
Several species have a subsutural and/or a supraperipheral (A.
sexlamellata) sulcus developed. Anatomy unknown.
Type species.— Anceyodonta difficilis, new species.
Anceyodonta represents a stage of evolutionary
specialization that is obviously derived from the
simulata group of Minidonta. Species of this complex
show some characters that are present in most or all
SYSTEMATIC REVIEW
179
Anceyodonta, but in most respects they are much
more similar to the typical Minidonta. Minidonta
micro also shows several strong similarities to Anceyo-
donta, but a greater number of differences. These
species were close to the threshold of becoming
Anceyodonta, but for various reasons have been
classified in the less specialized genus.
Some 12 characters of size, shape, sculpture, and
barriers generally present contrasting states in Mini-
donta and Anceyodonta. Scoring of these characters in
Table LXVIII shows that nine of the 12 Anceyodonta
have two-thirds or more of the advanced states, while
10 of the 12 characters are present in two-thirds or
more of the species placed in Anceyodonta. For
comparison, the five Minidonta that approach Anceyo-
donta in structure are included in the same table.
Three species, A. ganhutuensis, A. constricta, and
A. alternata, are included in Anceyodonta despite
showing relatively few of the specialized character
states. In all three, the minute or small size drastically
reduced the whorl count and thus eliminated two
characters in one change. A. ganhutuensis has the
strongly elevated spire, minute umbilicus, strong
secondary spiral cording, and widely spaced ribs
typical of Anceyodonta. The presence of only 3
parietals and three palatal traces can be correlated
with the very small size. A. alternata, known from a
single probably juvenile example, has the apertural
barriers, rib spacing, and secondary spiral cording of
Anceyodonta. Its departure from the Anceyodonta
pattern in shape, umbilical width, whorl count, size,
and spire depression can be viewed as secondary
modifications possibly resulting from a single mutation
that caused a radical change in coiling pattern, plus
the potentially juvenile size. A. constricta has a very
specialized umbilical pattern (fig. 82b) and lacks the
shape and sculptural features typifying Anceyodonta,
but the apertural barriers are so completely those of
Anceyodonta that I prefer to keep it in that genus,
despite its general similarity to Minidonta.
Both Anceyodonta constricta and Minidonta
taravensis could be transferred to the other genus and
such a placement defended. If additional material
becomes available, a more critical assessment of their
affinities may be possible. At present they can be
recognized as species that are transitional in observ-
able character states and whose generic placement
must be arbitrarily decided.
While in many respects speciation in Anceyodonta
is characterized by varying combinations of a few
differing features (secondary cording, presence or
absence of a sulcus, size of 1st palatal, position of
columellar barrier), there are a few striking variations
that require comment. The generic norm is a high,
dome-shaped spire, rounded above, and without
marked descension of the body whorl. In both A.
constricta and A. andersoni the spire is only moder-
ately and evenly elevated, while in A. alternata the
spire is actually depressed. Depression of the spire
normally is accompanied by widening of the umbilicus,
and both A. alternata and A. andersoni have wide,
regularly decoiling umbilici. A. constricta, however,
has a very strangely narrowed umbilicus (fig. 82b). The
only other Anceyodonta with a widely open umbilicus,
A. soror, attained this by extremely rapid decoiling of
the body whorl (fig. 83c). Other species have minute to
closed umbilici, and only in A. subconica do even a few
examples show slight umbilical decoiling (fig. 81c, f).
Sculpture in Anceyodonta generally is quite
widely spaced (table LXIX). Calculation of the mean
ribs per millimeter on the body whorl showed most
species with 6.3-8.2 ribs/mm. A. sexlamellata with 9.5;
A. densicostata with 11.1; A. subconica with 11.5; and
A. constricta with 13.0 had considerably more crowded
ribbing. In A. densicostata (fig. 87a) there is a clear
increase in number of ribs, hence greater crowding (see
table LXIX), but in A. subconica and A. constricta
the number of ribs on the body whorl is the same as in
much larger species.
The situation in A. obesa populations on Man-
gareva and Aukena offers data that bear on the
importance of this crowding. Comparing sample popu-
lations (table LXX) from the two islands demonstra-
ted that a 13.1 per cent change in diameter that is very
highly significant (with 62 df, "t" = 5.8735) resulted in
an insignificant change in rib count (with 24 df, "t" =
0.7910). Local dwarfing of one population apparently
left the total rib count unaffected, but altered the
spacing. The Mangareva shells of A. obesa averaged
8.81 ribs/mm., the Aukena specimens 8.11 ribs/mm. In
view of this effect, it is tempting to suggest that the
crowded ribbing of the very small A. constricta and A.
subconica indicates that these species were derived
from larger ancestors with the rib number remaining
constant, rather than to consider that they are
primitively small. Without stratigraphic data on
species occurrence, any phylogenetic conclusions are
premature. The above suggestion is offered at this time
to emphasize the complexity of minor changes within
Anceyodonta. A more detailed discussion of rib-
diameter relationships is given above (pp. 44-47).
Variation in the barriers is relatively minor (table
LXIX). Except in A. labiosa (fig. 87d, e), the parietals
extend more than one-quarter whorl, generally with 4
parietals elevated. Only in A. ganhutuensis and A.
sexlamellata are there normally only 3 elevated
parietals; in A. labiosa slightly more than one-third
the specimens have only 3 (the remainder have 4) and
in A. hamyana an equal number of specimens have 3
and 4 parietals. A. obesa, A. subconica, A. densicos-
tata, and A. soror normally have 5 major parietals,
while in A. difficilis the 4th parietal is reduced to a
threadlike trace without elevated posterior portion. A.
alternata and A. sexlamellata normally have 2
columellar barriers, while a 2nd one is rarely seen in A.
constricta. The normal endodontid pattern of the
columellar barrier lying parallel to the plane of coiling
V
-fa V
COOCQOCOD-C-
'
.
4-
x x x x x x
X X
(N CO
x x x x x x x
V
XXXXXXXXco
^
"A. *
X X X eo
X X X X X X X X X X X rt
&
i<
3
(7.X
*1
X X X «
X IN
XXXXXXXXXXXXN
X X X oo
, >
*.
X X X X X
X X X X 01
\
•*»
*
XXXXXXXco
• • X X X X X X
X
XXXXXXXXoi
•s
"5
X X
.XXXXXXXoo
rt
rfl
°
«
!
rt > 0
II!
««
180
I
I
I'
U
.
0|
+
10
(N| (Ml
co| co|
o
•a
I
o
Oi
co'
00
CM"
CO
in
CT1
CNl"
CO
CN!
t-
<N"
co
oo
O5
CNI"
CNl
I
CO
§
u
o
OO
en
o
CD
00
in
00
W
o
.c
+
CO
CO
IO
D
^^
u
X
P
Z 03
en
CNl
CO
in
CM
c~-
o>
CO
en
to
CO
CO
CO
tr-
CJ
CO
t-
IN
C—
CNl
CO
c-
OO
c-
io
CD
tr-
CD
t*
0
o
O
O
o
0
0
0
o
o
o
I
1
i
1
i
I
rH
CO
fr-
C^
rH
CM
'f
T-t
TH
OO
tr-
t-
0
CD
0
IO
s
to
CO
01
to
CO
CO
CM
CO
CD
to
CD
io
to
0
0
o
o
0
0
0
0*
O
O
o
en
CO
CO*'
O CD
rH
CO
CO
c-
m
o
t-
OO
OO
to
C^ IO
rH
CM
00
TH
o
CD
c-
CD
to
to ^f
c-
CD
t"
ID
C—
tr-
CO
0
O
o
o o
o
O
o
0
0
o
o
0^
CM*
S"
in
CNI"
CO*
CM
CM"
CM*
CD
CO*
co"
O5
0
CO*
in
co'
co'
TH
0
10
o
V
CO
1
i
1
1
t
1
1
cn
OS
CO
f—
^H
CO
CO
CO
CD
Cn
0
to
CM
•^
e-
CD
0
0
rH
TH
CM*
CM*
CM"
CM"
CM"
tN
CNl
CO
CO
CO
O
CNI
o
CM
CM CM
I
rH
CD
o
0
O
iH
to
IO
8?
rH
CM"
CM"
CO* CM*
<N"
CM
<N
co"
CO
CO*
co"
C?
c-
rH
o
CNl
CNl*
05*
CM
rH
CM
\n
IM"
OS
rH
O3
CM'
CO
CM"
CO
iH
co"
o
CO
CM"
t
co"
t
1
1
i
i
i
1
CD
OO
CO
rH
00
m
c-
TH
CM
rH
CN]
TH
rH
rH
c-
rH
tr-
CO
OO
00
rH
CM*
01
TH
OO
in
Sf
CNl
CD CM
00 0
X
o
V
CD
0)
c-
o
S
$
CD
CO
s1
CM
TH
Oi
CNl
CM
CM
CM
^— \
1
S
3
U?
en
CO
o>
CO
t"
00
TH
TH
TH
CD*
0
rH
O
0
rH
O
CNl
TH
0
4
1
CO
CD
I
rH
CO
CO
1
O
1
in
IT-
CO
0
o
CO
2-
CD
to
IO
CO
O5
t-
CO
TD
CO
c="
0^
CO
CD
¥
CD'
cT
of
U
O
o"
CTi
o
O5 CO
CO
in"
O5
V
Oi
rH
CT>"
fH
"^f
c-
0>
t— ^1
CO
CO
CO
o
c-
Ob
D-
vt
S
CO
TH
CO
nJ
z
s
•
-d
£
181
10
CO
I
^-v x~*
0 10
CO C-
0
IT-
co"
o
o
O
8
co o
o •»f'
m'? co 71
CM'
o ?
CO
f- ?'
0 "'
CO
o> i
U4
H
Ul
00 §
00 .
CO rH «>_ 5
2 <=>
•* O5
ss
CM ,-L
C-_ (M
w cc
1-1 LO
1
3
• o
rH 2
-H C,
° u£ => V
3s
SS
<*> 00
Ss
3
i
CO
oo
O C-
C-
iH
CO
CM ^
CM
CO
rH
OH
UJ
a.
10'
c- c-
CM'
co"
CO
•*"
o
o
CO
iH
CO
IO
IO
4
CO
00 IO
CO IO
I
IO ^>
+
00 '
IO
CO
CO
CO
>s
IO
CO rH
CO C-
I
CO CM
_o
05
CO
CO
N
CO
c-
co ?'
CM
(N
C-
oo °'
o
CO
t-
U3
O
rt
CO
co ?
CO
c-
co ?'
t-
t-
co
Q
CM ]
o
oo
CO?
IO jli
00 OJ
CO o
10 f^
CO p-
CO
g
1
0 ^
§8
o g
0
O
IO
§s
O txi
°. ^
rH to
0 to
o
0
Q
O o
°' £.
O o
o
o
0 o"
°' £.
0 o*
0 o
o
§
"K
CO
10
c-
•* ""
oo
CO
IO
CO
CO
CO
o
CO "~
CO
CM ^
CO
00
00
e-
CD
CO
1/3
IO
f
CO
cr-
c-
o
CM
CO
CO
CO
J2
OO
"S3
X
sr
CM
00
0
co
o
o
•H
00
CO
CO
00?
<M &
O 02
CO 0>
0 CM
id
00
o
-H
OO
co V
CO 02
O CM
/ \
s
CM
CM
CO
CO*
?s
IO
o
CM
IO
rH
CO*
CM
CM
-H
1O
O
CO
rH
CO*
oo
o
^e£
0
-H
CM*
3 si
° si
°
z
C~
CM
O
IO "~
rH
s
CM
(M
CO
co'
CM'
CM
oo'
i/?
rH
•*t
00
O
TO ^'
CO
CM'
i
CO ?
0?
,_,
^* Oi
O pQ
C-
O
CO
CO
S J2
Is
0
?4 rH
0
rH
°' d
o" CM'
0
-+1 ^^
rH
-H
IO
*^
t—
o
rH
CO
0
CO
IO
O
rH
CM'
CM'
CM'
CM*
CO
c-
03
•
O
0
c
V
f
E
JTj
CO
CO IO
^
g
o
rH rH
X
v>
i
CO
43
E
0 CM
o
s
3
3
"o
u
a.
a
O
rH CD
^* CO
C71 oj Oi (^
n)
o
--o
o
E
2
3
3
0(
00
<
subcon
a. 3 a, "3
co < pa •<
constrl
OL-
DS
CO
CO
o>
«s
C rH
82
U P
oo
00
CO
£
CO
t-
co
CO
CO
CO
S S r"S
So g>
oa c-- <5
a. co ^
m 01 2
co
CO
aa
a,
oa
o
U3
00
S 2
rH 3
oa
OH
oa
(N
CO
oo
oo
S1
2 «
co >;
O, "•
oa H
182
*— s
0
CO
CD
0
CO
oo"
os"
<N
OS
CM
IO ,
•* o
0 ^
2s-
CO ^
• OS
f"1 rH
(N *°.
•a 5
CD
co
-H •_-
rH
CO
-H G»
c-
co
co"
rH
IO
CN
in
rH
oo"
•^
00^
>T
co-t
CO
+ CO
00 '
-^ co
rH
CO
CO 1
CD
4"
>T
co^
f
fL
1O
..— v
O
co
c-
P
C-
^~v
oo
c-
IO ro
o £
o ^
co ?'
OO uj
0 C-
o
2 rH
og
°'s
c-
co
is,
OS
10
c~
°'e
CM
CO
o
o
O
rH
CO
s~*
rH
<N
rH
(N
OS «
CO uj
0 to
0?
"5 00
0 00
CN?
CO u3
°. *""
?si
CN
i£
CN
O
0 (N
-H i_-
O
O
CN
co'
CO
os"
rH
s?
CO
f?
g?
f?
Sg
co ^
2S
id
CO
o
|si
<N
id
00
o
<N
CN
g|
-H C-
CO
CO
OO
o
o
OS
— 1 $ °°
«i 3 r~*
" 3
CO
00
<4
BC
CN
O
c-
CN
CO
OS
00
rH
to
e-
eft
os
2
00
2
CO
rH
o
0
2
"S
u
CQ
0,
Da
•o
O
O
^^
0
0
J.—^
O
1O
m
o
0
0
f
,
TH
.
00
rH
^
,
^
CO
CO
CD
LOSED
Q S?<
g s?
«e
CO A (N
(N § 0
00 . CO
<N*S CM*
-H Cl- -H
o
CO
CD
o
OS
c-
o
rH
1
rH
CO
rH
rH
ti
1
O
in
rH
rH
rH
co
-H
1
oi
rH
U
u s
O CD
00 CO
10
IN
rH
CM
CO
c-
CO IO
TH
CO*
CM*
CM CN
TH
CN
CO
oo
00
^
CO
00~
^— \
CN
H-
oo
"m
4^ A€
co I~l oo
IO
co
CO
'.H"
4
00
00
^
c-
>c- >c-
*^* CO ^*^
CO
CD
^*^
CO
^s*
IO
CO
CD
oo
\
i^ | rH
CD -S? CO?
CO -^ CO
1
CD
1
CO
rH
CO
1
oo
CO
CO
1
c-
co 'o
rH
CO
c-
10
co^
!S
IO
IO
IO
IO
U3-
to
t- co"
o"
cT
o"
CD
c?
oo
OO CD
CO
co
00
TJI
c-
C- C-
c-
c-
CD
c-
c-
03
0
•* ? 00 °
C- ? CO
o
H
O
CO
o
o"
0
oo
c- rH e- oo
O ^Q O 1/3
0 10 0 co
OS ^i 10
S S 2
O to °
CM
IO
CO
CD
O
O
00
10
00
o
o
co
rH
CO
rH
O
CO
CO
0
-H
o
? S °' S
0* 0' 0*
-H ci. •«
o
o
-H
o
o
•u
O
-H
0
IN
00 O
t- 1O
r-l
c-
CO
CO
OS o
CO CO
CO
00
rH
c-
CD C^
to co
CO
CD
C-
0
0 0
o o
0*
o
o
So"
5" c-"
^
c-
^
^
,-,
IO
o o
o
10
*3*
"3*
c-
IO
co"
CO "f >-H T
O 1 ^
•*"
10
-*'
CN
•*'
CM
•**
CO
0
IO
CO
10 rH « 00
° 00 . °
50 rH «>
0 " 0
rH
c-
S
c-
00
CO
o
oo
O
rH
IT-
OS
0
-H
CM"
°" CM* 0 CO*
-H C- -H ii
0* co* 0*
•« •— ' -H
co.
o
-H
co<
o
-H
2-
0
-H
2-
CM
O IO
00 O
00
rH
CO
OS
CO 10
CO O
TH
O
co
CN
00 CO
co" •*'
*
"*'
"*
io"
OO rH
r~.
^
rH
oo
oc?
IO
rH OO
OS
rH
O
rH
CO
0
CN
OS i rH <?
OS ^ C-
CO*
|
00
co"
1
c-
CO*
^*
co'
1
co
o
10
CO
<= 00 ° rH
SS S
(N
CO
0
CO
co
10
o
CO
CN
00
0
10
o
^
0 rH* 0 (N*
o c£ <=
CN
o
(N
o
CM
o
(N
41
"-*
-« — -H ~_-
rH 00
CM ^ -^
4*
^
-H
CO
-H
CM
rH
CO •<*
•<JI t-
CO
c-
rH
CN
CN* (N
CN* CN"
CN
CN*
CO
$
/-N
CO 0»
CD
^
*"*
1
CD 1
i— i
1
•
CD
. CO
•
OJ
4^
IO
CN t-
CD
CD
00
41 w'
S
^,-'
o
•
•
c-
00
t-
o
•* oo
CO Tf
c-
CO
CD
CO
CO rH
rH rH
iH
rH
CQ
C-
^
co
1
3
1
IT-
CD
O .
CD OS
CD CO
0
o
OS
OS
oT
OS
a
C- CO
OS nj as
03
c-
CO
CO
•3
CO
CO
V
00 TH
OO > 00
CO O CO
>
V
oo
co
oo
CO
oo
co
5
TH
M
«t
rH CtJ OS
3 "^ <3 1~l
t-t
ft
iH
<fl
rH
«
rH
M
oj
s
J3
O
2
CQ
Q-,
CQ
OO
c
rt
2
§S g|
OH 3 -H OH
CD *^ -^ CQ
>I« i
^ « 2 M
^ CM i^i Bj
g*
a
1
1
m
<
CQ
%
DO
183
184
SOLEM: ENDODONTOID LAND SNAILS
is found in four species (A. ganhutuensis, A. constricta,
A. andersoni, and A. alternata); it slants downward
across the columellar callus in five species (A.
subconica, A. sexlamellata, A. densicostata, A. obesa,
and A. hamyana); and is displaced onto the basal lip
in three species (A soror, A. difficilis, and A. labiosa).
Although all species have 4 major palatals, in only
five Anceyodonta is the 1st palatal equal or nearly
equal in size to the 2nd (A. subconica, A. ganhut-
uensis, A. alternata, A. andersoni, and A. hamyana,
see fig. 82). The other species have the 1st palatal
greatly reduced in size, although it remains larger than
the adjacent palatal traces. In some specimens (for
example, fig. 89f) the 1st palatal is smaller than the
palatal trace located between the 2nd and 3rd palatals.
Gambiodonta species have this reduction carried much
further. In both G. grandis and G. mirabilis the lower
palatal cannot be distinguished from the accessory
traces. There is little correlation between position of
the columellar barrier and proportionate size of the 1st
palatal, and none between shell diameter and
proportionate size. No specimens with a displaced
columellar have a large 1st palatal, but species with a
slanted columellar (A. subconica and A. hamyana)
have a large 1st palatal although others (A. densicos-
tata and A. obesa) do not.
The two largest Anceyodonta, A. hamyana and A.
labiosa, have, respectively, none or zero to two palatal
traces. A. sexlamellata has the greatest number
(normally up to 11) and most species have more than
four. Utilizing the term "traces" is somewhat mis-
leading, since in certain species (figs. 81d; 83a, c, e; 89f)
the traces between the middle palatals are elevated
and expanded miniature replicas of the major palatals.
If not clearly marked by their position as being
homologous to the reduced traces normally seen (figs.
82a, d, e; 83f; and 86a, c-e) and remaining distinctly
smaller than the major palatals, they would be
considered fully developed barriers. This very strong
development of accessory barriers is unique to the
Mangarevan taxa.
Two other shell features require comment. The
development of secondary spiral cording, usually most
clearly visible below the periphery, is one of the most
characteristic features of Anceyodonta. Cording is
absent only in A. constricta, A. densicostata, and A.
obesa; present or absent on an individual basis in A.
sexlamellata and A. hamyana; and always present on
the other seven species. Unless the sculpture is so worn
that even major ribs are not clearly marked, the
cording can be seen without difficulty. Several species
have a strong subsutural sulcus (A. subconica, A.
soror, A. difficilis, A. sexlamellata, and A. obesa) and
normally there is a prominent supraperipheral sulcus
in A. sexlamellata (fig. 86e). In some specimens (fig.
89d) the sulcus may be very weak and detectable only
as a flattening of the rib contour, but usually (fig. 88a,
c) it is quite prominent.
While three pairs of closely related species can be
recognized, no general hierarchial arrangement could
be devised. A. alternata and A. andersoni, both
restricted to Mangareva Islet, agree in the wide
umbilicus, low spire, presence or occasional presence of
2 columellar barriers, absence of a subsutural sulcus,
presence of spiral cording and spacing of the ribbing.
The small recorded size of A. alternata is caused by
the single specimen being subadult. A. soror and A.
difficilis differ most obviously in umbilical width (fig.
83b, d), but also show minor differences in size, H/D
ratio, and barriers (figs. 84, 85). They agree in all
details of sculpture, have the columellar barrier
deflected onto the basal lip, and show only minor
changes in palatal and parietal barriers. Occurring
essentially at the same stations, they may be
chronologically separated species. A. obesa and A.
densicostata are even more closely related, differing
primarily in the rib spacing and the subsutural sulcus.
The other species cannot be separated in pairs and
none of the three pairs outlined above show strong
similarities to other species.
Geographic distribution yields almost no informa-
tion on relationships. Two of the three species pairs
cited above are restricted to Mangareva Islet. A. obesa
is found on four islets (table LXXI) and A. densicos-
tata is restricted to Mangareva Islet. Derivation of
densicostata from obesa is a distinct possibility. Of the
12 Anceyodonta, two (A. hamyana and A. sex-
lamellata) were found on five islets; one (A. obesa) on
four islets; one (A. subconica) on three; two (A.
labiosa and A. densicostata) on two islets; and the
remaining six species are known only from a single
islet. Of these six, A. constricta was found on Aukena
and the other five solely on Mangareva. Taravai Islet,
from which only 18 Anceyodonta were collected, had
three species; Agakauitai and Akamaru, from which 61
and 215 specimens, respectively, were collected each
had four species; Aukena Islet, from which the fossil
beds yielded 857 specimens, had six species; and
Mangareva Islet, where 332 Anceyodonta were collect-
ed, had 10 species.
Collecting effort on the islets was not equivalent,
with much more effort being invested in the collections
from Mangareva and Aukena Islets, and very little
time spent on Taravai and Agakauitai.
As in the collections of Gambiodonta (pp. 432-
434), there were instances where collecting stations
were taken within very close proximity of each other:
1) on the same day and by the same people (Stations
88 and 102 on Aukena); 2) by the same people on
different days (Stations 187 and 189 near Rikitea,
Mangareva); or 3) by different people on different days
(Stations 142 and 277 near Ganhutu on Mangareva).
On a large scale map, these stations are not separable
(see Part II), but were at least 100-300 ft. apart. If the
proportion of species collected at each station is
expressed as a per cent of the entire sample (table
LXXII), it is obvious that the relative abundance
TABLE LXXI. - GEOGRAPHIC DISTRIBUTION AND RELATIVE ABUNDANCE
OF MANGAREVAN ENDODONTIDAE
/
/ /*
<* ^ N
Anceyodonta
ganhutuensis
6
6
1
subconica
104 2
94 8
3
constricta
7
7
1
andersonl
25
25
1
alternata
1
1
1
dlfficilis
26
26
1
soror
19
19
1
sexlamellata
577 47 20?
i 265 44 13
5
densicostata
31
30 1
2
obesa
416 4 J
1 302 107
4
labiosa
27 5
i 25 :
2
hamyana
244 8 5
! 164 66 4
5
Rikitea
insolens
1
•1
1
Minidonta
micra
228
228
1
Simula ta
32 1
30 1
3
taunensis
2
C
> 1
taravensis
2
2
1
extraria
3
111
3
Gambiodonta
agakauitaiana
17 17
1
p. pilsbryi
88
88
1
p. aukenensis
79
79
1
mangarevana
6
6
1
mirabilis
41
4 37
2
tumida
33
33
1
grandis
259 32
227
2
TOTALS
2,274 111 215
1,426 499 21 2
]
85
s-
186
SOLEM: ENDODONTOID LAND SNAILS
TABLE LXXII. - PERCENTAGE SPECIES COMPOSITION OF MANGAREVAN ANCEYODONTA
IN SELECTED SAMPLES
Aukena
Mangareva
Station Station
88 102
ganhutuensis
subconica 7.3 22.1
Rikitea
Station Station
187 189
2.6
5.3 4.7
15.8 20.3
4.7
39.4 23.4
23.7 34.4
13.2 12.5
Station
142
2.5
22.5
7.5
7.5
2.5
25.0
32.5
Ganhutu
Station
277
2.0
4.1
6.2
2.0
6.2
4.8
17.9
35.3
21.5
andersoni
difficilis
soror
sexlamellata 28.8 46.5
densicostata
obesa 50.4 24.2
labiosa 4. 6
hamyana 8.9 7.2
Number of specimens 434 275
38 64
40
145
varied greatly within each pair of stations. Since the
size range of these specimens is rather small, and the
collectors could not have been aware that such a
diversity of forms was involved, I am confident that
these differences reflect stratigraphic differences in the
deposits.
The disparity between islets in collecting effort
and gross differences between adjacent stations in
species composition prevent any meaningful
comparisons of faunal differences. Available data do
suggest that attempts to make stratigraphic collec-
tions on at least Mangareva and Aukena might
provide considerable information concerning temporal
variations in species abundance, and possibly might
yield data on phylogeny within both Anceyodonta and
Gambiodonta.
The species sequence adopted below goes roughly
from the smallest to the largest in size, deviating only
when necessary to place pairs of species together.
KKY TO THE GKNI'S Anceyodonta
1. Apex and spire markedly elevated; umbilicus usually very
narrow; if widely open last whorl dec-oiling more rapidly 2
Apex and spire flat or slightly depressed; umbilicus widely open,
regularly decoiling, contained less than 3.00 times in the
diameter Anceyodonta alternata, new species
2. Columellar barrier displaced onto basal lip (fig. 83e) 3
Columellar barrier parallel to plane of coiling (fig. 81a) or
slanted downward (fig. 89d) 5
3. Subsutural sulrus present (fig. 89a); parietals 4 or 5; palatal
traces two to six 4
Subsutural sulcus absent (fig. 90a); parietals 3 or 4; palatal
traces zero to two Anceyodonta labiosa. new species
4. D/U ratio less than 5.00 Anceyodonta soror, new species
D/U ratio more than 7.00.
Anceyodonta difficilis, new species
5. Lower palatal barrier much smaller than 2nd (fig. 87e) 6
Lower palatal barrier equal to or slightly larger than 2nd (fig.
90d) 9
6. No subsutural or supraperipheral sulcus 7
Distinct subsutural or supraperipheral sulcus present (fig. 86c).
8
7. Diameter less than 2.4 mm.; H/D ratio less than 0.600.
Anceyodonta constricta, new species
Diameter more than 2.6 mm.; H/D ratio more than 0.600.
Anceyodonta densicostata, new species
8. Only 1 columellar barrier, 5 major parietals; never a suprape-
ripheral sulcus Anceyodonta obesa, new species
Always 2 columellar barriers, 3 major parietals; usually a
supraperipheral sulcus present.
Anceyodonta sexlamellata (Pfeiffer, 1845)
9. Columellar barrier parallel to plane of coiling (fig. 81a) 10
Columellar barrier slanting downward across columellar callus
(fig. 89d) 11
10. Diameter less than 2.3 mm.; 3 parietals.
Anceyodonta ganhutuensis, new species
Diameter more than 2.8 mm.; 4 parietals.
Anceyodonta andersoni, new species
11. Diameter less than 2.6 mm.; parietal and palatal traces present.
Anceyodonta subconica, new species
Diameter usually much more than 3.0 mm.; no parietal or
palatal traces Anceyodonta hamyana (Ancey, 1889)
Anceyodonta ganhutuensis, new species (Cooke &
Solem). Figures 81a-b.
Diagnosis. - Shell minute, diameter 1.69-2.19 mm. (mean 1.87
mm.), with 43/<-57/8 very tightly coiled whorls. Apex and spire very
strongly elevated, slightly rounded above, last whorl descending a
little more rapidly, H/D ratio 0.741-0.839 (mean 0.789). Umbilicus
FlG. 81. a-b, Anceyodonta ganhutuensis, new species. Station 142, Ganhutu, Mangareva Islet, Mangareva, Gambier Islands. Holotype.
BPBM 9638; c-f, Anceyodonta subconica, new species, c-d, Station 102, Aukena Islet, Mangareva, Gambier Islands. Holotype. BPBM 9662; e-f,
Station 88, Aukena Islet, Mangareva, Gambier Islands. Paratype. BPBM 9411. Scale lines equal 1 mm. Drawings by YK reproduced through the
courtesy of Bernice P. Bishop Museum.
187
188
SOLEM: ENDODONTOID LAND SNAILS
minute, partly covered by reflected umbilical lip, contained 10-20.6
times (mean 15.8) in the diameter. Postnuclear sculpture of very
large, prominent, protractively sinuated radial ribs, 34-54 (mean 40.3)
on the body whorl, whose interstices are 2-3 times their width.
Microsculpture a lattice of very fine radial riblets, five to nine
between each pair of major ribs, crossed by slightly finer and more
crowded spiral riblets, plus a secondary sculpture of low, broadly
rounded spiral cords, visible mainly on base of shell. Sutures
impressed, whorls evenly rounded, slightly compressed laterally
below periphery. No sulcus present. Aperture ovate, inclined about
10° from shell axis. Parietal barriers 3, extending posteriorly beyond
line of vision: upper a high, slender blade with gradual descension
over visible anterior third, posterior section expanded and serrated;
2nd equally high posteriorly, anterior visible half threadlike; 3rd with
posterior portion reduced in height, threadlike portion slightly longer,
more gradual descension from elevated portion. Columellar wall with
very thick heavy callus extending onto basal margin, which is
surmounted by a raised threadlike ridge, expanded and serrated
posteriorly, anteriorly narrowing and sinuately twisting across callus,
stopping well short of lip edge. Palatal barriers 4, extending
posteriorly beyond line of vision, plus three very fine, threadlike
traces: lower moderately recessed, bladelike, weakly expanded above
with gradual anterior descension; 2nd equal in height, a trifle
slenderer, more deeply recessed and with sharper anterior descension;
3rd same as 2nd, but a little more recessed; 4th greatly reduced in
height, lying opposite 1st parietal, a narrow V-shaped ridge, less
deeply recessed than lower palatals. Accessory traces short, very fine,
located between 1st and 2nd, 2nd and 3rd, and above 4th palatals.
The extremely elevated spire, minute size and
presence of only 3 parietals immediately separate
Anceyodonta ganhutuensis from other species of the
genus. The only species that even approaches it in size,
A. constricta, A. subconica and A. alternata, have 4 or
more parietals, are much more depressed (A. alternata
and A. constricta), and have much more crowded
ribbing (A. subconica and A. constricta).
Description. — Shell minute, with S1^ tightly coiled whorls. Apex
and spire very strongly elevated, last whorl descending a little more
rapidly, H/D ratio 0.788. Embryonic whorls 1M>, sculpture eroded.
Lower whorls with slightly protractive, wide, prominent, radial ribs,
54 on the body whorl, whose interstices are approximately twice their
width. Microsculpture a lattice of extremely fine radial riblets, five
to nine between each pair of major ribs, and slightly finer and more
crowded spiral riblets, plus a secondary sculpture of low, broadly
rounded spiral cords, visible mainly on base of shell. Sutures
barely perforate, contained 13.2 times in the diameter. Color light
yellow-brown except where leached from shell. Aperture ovate,
somewhat flattened below periphery, inclined about 10° from the
shell axis. Parietal barriers 3, extending beyond line of vision: upper
a high blade, descending gradually over anterior third, posterior
elevated portion serrated and slightly expanded above; 2nd with
posterior section the same as 1st, anterior visible half threadlike; 3rd
with posterior section reduced in height, threadlike portion longer,
with less sharp descension from elevated portion. Columellar barrier
lying on very heavy callus, a low ridge parallel to plane of coiling,
elevated and serrated above posteriorly, anteriorly angling across
callus, stopping well short of lip edge. Palatal barriers 4, extending
beyond line of vision, bladelike ridges, plus three low accessory
traces: lower nearly reaching lip edge, with rather gradual anterior
descension; 2nd equal in height, slightly recessed, with sharper
anterior descension; 3rd identical to 2nd; 4th greatly reduced in
height, a narrow V-shaped ridge, less deeply recessed. Accessory
traces short, narrow threadlike ridges between 1st and 2nd, 2nd and
3rd, and above 4th palatals. Height of holotype 1.71 mm., diameter
2.17mm.
Holotype. — Gambier Islands: Mangareva, Station
142, inland 150 ft. from Ganhutu Bay at 6 ft.
elevation. Collected by Yoshio Kondo and C. M.
Cooke, Jr. on June 3, 1934. BPBM 9638.
Range. — Known as subfossil material from two
localities on Mangareva Islet, Gambier Islands.
Paratypes. — Sames as list of material.
Material. — Mangareva Islet: near Ganhutu (Sta-
tions 139, 142, 277) on flat ground near sea level (5
specimens, BPBM 9638, BPBM 138972, BPBM
141272); in the north part of Rikitea (Station 187), a
subfossil deposit at 6 ft. elevation (1 specimen, BPBM
9647).
Remarks. — The type is unusual only in having
the ribbing more numerous and crowded than in the
other examples. No variation was noted in the barriers.
Although reaching the size range of Minidonta
(tables LXIII, LXIX) and having only 3 parietals, the
very elevated spire, secondary spiral cording, quite
narrow umbilicus, and V-shaped upper palatal lying
opposite the 1st parietal relate ganhutuensis more to
Anceyodonta.
Anceyodonta subconica, new species (Solem &
Cooke). Figure 81c-f.
Diagnosis. - Shell very small, diameter 1.94-2.50 mm. (mean
2.20 mm.), with 4%-7 tightly coiled whorls. Apex and spire very
strongly elevated, slightly rounded above, last whorl not descending
more rapidly, H/D ratio 0.603-0.762 (mean 0.686). Umbilicus
moderately open to very small, last whorl decoiling more rapidly,
contained 4.47-14.8 times (mean 7.67) in the diameter. Postnuclear
sculpture of narrow, prominent, rather crowded radial ribs, 58-94
(mean 79.7) on the body whorl, whose interstices are less than twice
their width. Microsculpture a lattice of very fine radial riblets, four
to seven between each pair of major ribs, crossed by finer and more
crowded spiral riblets, with a secondary sculpture of low, rounded
spiral cords, whose size and spacing is about equal to that of the
major radial ribs, and which are generally absent or reduced near
periphery. Sutures shallow, whorls strongly rounded above and on
umbilical margin, slightly compressed laterally, with a weak
subsutural sulcus present. Aperture ovate, inclined less than 5° from
shell axis. Parietal barriers 5, rarely 4 or 6, extending posteriorly
beyond line of vision, with four to six slender low traces: 1st and 3rd
parietals more elevated than 2nd, 4th and 5th; all parietals low and
bladelike, visible posterior half expanded and serrated above,
anterior 3rd low and threadlike, first 3 parietals extending
progressively further anteriorly, 4th and 5th very slightly recessed
from anterior end of 3rd. Upper parietal trace slender, prominent,
located just below parietal-palatal margin; remaining three to five
traces lower, broader, located between major parietals, not extending
anteriorly to end of threadlike portions. Columellar barrier a low,
bladelike ridge, twisted slightly downward just before reaching edge
of heavy columellar callus and terminating. Palatal barriers 4,
extending posteriorly about three-eighths of a whorl, slightly reduced
in height from bottom to top, normally with five, rarely six, much
lower palatal traces. Palatal traces located between 1st and 2nd, 2nd
and 3rd, 3rd and 4th, and above 4th palatal, rarely a very faint
palatal trace between columellar and 1st palatal tooth.
Anceyodonta subconica is most readily recognized
by having the palatal barriers regularly decreasing in
size from bottom to top and its small size. Other
Anceyodonta have the 1st palatal distinctly smaller
than the 2nd, or if equal in size are very large (A.
hamyana and A. andersoni), with a depressed apex (A.
alternata), or with an extremely high spire and widely
spaced ribbing (A. ganhutuensis).
SYSTEMATIC REVIEW
189
Description. — Shell very small, with 6'< relatively tightly coiled
whorls. Apex and spire strongly elevated, last whorl not descending
more rapidly, H/D ratio 0.722. Embryonic whorls 1%, sculpture
eroded. Postnuclear whorls with narrow, prominent, crowded, almost
vertical radial ribs, 85 on the body whorl, whose interstices are 1-2
times their width. Microsculpture eroded, faint traces of secondary
spiral cording occasionally visible. Sutures shallow, whorls
with a slight subsutural sulcus, somewhat laterally compressed,
strongly rounded on basal margin. Umbilicus very narrowly open
internally, becoming slightly more widely open on last whorl,
contained 6.00 times in the diameter. All color leached from shell.
Aperture ovate, somewhat compressed laterally, inclined less than 5°
from shell axis. Parietal barriers 5, extending posteriorly beyond line
of vision, with three indistinct parietal traces: major parietals with
anterior visible third threadlike, posterior portions distinctly raised,
expanded and serrated above; 1st and .'ird parietals larger than 2nd,
4th and 5th; upper parietal trace slender, prominent, located just
below parietal-palatal margin, remaining faint traces between 1st
and 2nd, 2nd and 3rd parietals. Columellar barrier a small threadlike
ridge reaching top of columellar callus, only slightly declined
anteriorly from plane of coiling. Major palatal barriers 4, extending
posteriorly three-eighths of a whorl, lower 3 strongly elevated,
rounded and serrated above, descending gradually to front edge of
apertural callus, progressively reduced in height from bottom to top;
upper palatal a lamellar ridge lying opposite and pointing toward the
upper parietal. Accessory palatal traces located between the major
palatal teeth with two additional ones above the upper. Palatal
traces progressively reduced in size from bottom to top. lower trace
with form of major palatals. Height of holotype 1.71 mm., diameter
2.37 mm.
Holotype. — Gambler Islands: Mangareva, Station
102, Aukena Islet, first cave east of gap. Collected by
Donald Anderson on May 28, 1934. BPBM number
9662.
Range. — Agakauitai, Mangareva and Aukena
Islets, Mangareva, Gambier Islands.
Paratypes. — Same as list of material.
Material. — Mangareva: Aukena Islet (Stations
88, 102, 103) near the gap (94 specimens, BPBM 9410-
1, BPBM 9662-3, BPBM 138798); Agakauitai Islet,
northwest side (Station 195), 100 ft. inland (2
specimens, BPBM 9673); Mangareva Islet, 100-200 yd.
inland, Ganhutu (Station 277) at northeast end (6
specimens, BPBM 9644); Mangareva Islet, vicinity
(Stations 187, 189) of Rikitea (2 specimens, BPBM).
Remarks. — In possessing nearly equal parietal
barriers, and in having the major palatals progressively
reduced in size from bottom to top, Anceyodonta
subconica departs from the usual pattern of Mangare-
van shells. In most other Mangarevan species there are
distinct differences in size of the various barriers, and
the lower palatal normally is greatly reduced in size.
In the above respects, A. subconica resembles more
closely some of the Austral Island Minidonta. The
presence of so many Anceyodonta characteristics in A.
subconica (table LXVIII) unquestionably places it in
the latter genus. A. subconica was a relatively
common species on Aukena, and only sparsely repre-
sented on Mangareva and Agakauitai Islets. The
rather crowded radial ribbing (fig. 81d, e), averaging
11.5 ribs per mm., is unusual for the Anceyodonta,
where the average of eight species with "normal"
ribbing is only 7.41 ribs per mm. As indicated above, it
is possible that A. subconica is secondarily reduced in
size rather than being primitively small.
A large specimen of subconica, diameter 3.03 mm.,
from Aukena (BPBM 9411) has the parietal barriers
reduced in size (fig. 81f) and some of the palatals
smaller than in the normal specimens. I consider that
it is a gerontic individual.
Anceyodonta constricta, new species (Cooke &
Solem. Figure 82a-b.
Diagnosis. — Shell very small, diameter 2.09-2.28 mm. (mean
2.20 mm.), with 5'/2 - 5% rather tightly coiled whorls. Apex flat, spire
moderately elevated, last whorl descending only slightly more
rapidly, H/D ratio 0.507-0.576 (mean 0.553). Umbilicus strongly
constricted with a weak basal sulcus, very narrow, U-shaped, last
whorl dec-oiling more rapidly, contained 6.90-22.7 times (mean 12.8)
in the diameter. Postnuclear whorls with narrow, crowded, slightly
protractively sinuated radial ribs, 86-95 (mean 90) on the body whorl,
whose interstices are 2-4 times their width. Microsculpture of fine
radial riblets, five to eight between each pair of major ribs, crossed
by distinctly finer and more crowded spiral riblets. Sutures shallow,
whorls strongly flattened laterally and on inward extending basal
margin. Aperture compressedly ovate, lengthened basally, inclined
less than 10° from shell axis. Parietal barriers 4, extending slightly
more than one-quarter whorl, almost always with two accessory
traces: upper a high lamellar ridge, expanded and serrated above on
posterior two-thirds, anterior quarter a raised threadlike ridge; 2nd
lower than 1st, threadlike portion a little longer, with more gradual
descension from elevated portion; 3rd higher than 1st posteriorly,
expanded edge slightly twisted upward; 4th slightly to greatly lower
than 3rd posteriorly, threadlike anterior portion longer. Accessory
traces located above 1st and between 1st and 2nd parietals.
Columellar barrier a low, rounded threadlike trace parallel to plane
of coiling, partly crossing thick columellar callus. Rarely a narrow
superior columellar barrier present. Palatal barriers 4, extending
nearly one-quarter whorl, plus usually five accessory traces: lower
basal in position, reduced in height, with rather sharp anterior
descension, slightly recessed; 2nd much higher, lying opposite 3rd
parietal, less recessed, with a little more gradual anterior descension;
3rd equal in height to 2nd, lying opposite 2nd parietal; 4th a much
lower, V-shaped, high ridge lying opposite 1st parietal. Accessory
traces located between each pair of palatals and two above upper
palatal. Latter occasionally absent.
Anceyodonta constricta is unique within the genus
for its umbilical configuration. Constriction of the
opening has produced a weak basal sulcus (fig. 82b)
very like that of the Rapan Rhysoconcha vari-
umbilicata (fig. 112b). The small size and relatively
low spire of constricta combine with the basal sulcus
to separate it from other Anceyodonta.
Description. — Shell small, with 5'4 tightly coiled whorls. Apex
flattened, spire moderately and evenly elevated, H/D ratio 0.576.
Embryonic whorls T'/s with only faint traces of microradial ribbing.
Postnuclear whorls with closely set, slightly protractively sinuate
radial ribs, 95 on the body whorl, whose interstices are 2-4 times
their width. Microsculpture of fine radial riblets crossed by finer and
more crowded spiral riblets. Sutures relatively shallow, whorls
rounded above, strongly flattened laterally and on base. Color white
with irregular, zigzagged, reddish flammulations. Umbilicus closed by
a flattening and extension of the basal shell margin, contained 11
times in the diameter. Umbilical margin shouldered with a basal
concavity above. Parietal barriers 4, extending beyond line of vision,
with two accessory traces: upper medium sized, anterior quarter
threadlike, becoming elevated, rounded and minutely serrated above
posteriorly; 2nd parietal much lower with only weakly expanded
upper portion; 3rd parietal much higher with expanded top slightly
twisted upwards; 4th parietal with more broadly expanded top and
FIG. 82. a-b, Anceyodonta constricta, new species. Aukena Islet, Mangareva, Gambler Islands. Holotvpe. BPBM 9660; c-d, Anceyodonta
alternata, new species. Station 187, Mangareva Islet, Mangareva, Gambier Islands. Holotype. BPBM 141661; e-f, Anceyodonta andersoni, new
species. Station 142, Mangareva Islet, Mangareva, Gambier Islands. Holotype. BPBM 138936. Scale lines equal 1 mm. Drawings by YK
reproduced through the courtesy of Bernice P. Bishop Museum.
190
SYSTEMATIC REVIEW
191
twisted more sharply upward. Accessory traces located above 1st and
between 1st and 2nd lamellae. Columellar barrier a low threadlike
ridge, parallel to plane of coiling, partly crossing columellar callus.
Palatal barriers 4, extending one-quarter whorl, plus five accessory
traces: lower reduced in height with very gradual anterior descen-
sion; 2nd very high, lying opposite 3rd parietal, long and bladelike,
expanded and serrated above, with sharper anterior descension; 3rd
same as 2nd, with more gradual anterior descension; 4th a
prominent, V-shaped ridge lying opposite 1st palatal, much lower
than 3rd palatal. Accessory traces located between each pair of
major palatals and two above 4th palatal. Height of holotype 1.25
mm., diameter 2.17 mm.
Holotype. — Gambler Islands: Mangareva, Aukena
Islet. Collected during Mangarevan Expedition. BPBM
9660.
Range. — Known only from the type collection.
Paratypes. - BPBM 9660.
Remarks. — One of the seven examples had the
two upper parietal traces absent. Otherwise the
barriers showed no significant variations.
Unfortunately, the station number was not avail-
able, so we do not know exactly where on Aukena the
specimens were collected. The constricted umbilicus is
diagnostic and at once separates Anceyodonta con-
stricta from the other Mangarevan endodontids.
In having a low spire, few whorls, very crowded
ribs, no sulcus or secondary spiral cording, and being
quite small in size, A. constricta differs considerably
from the other Anceyodonta. Its inclusion in Anceyo-
donta rather than Minidonta has been based on the
apertural barriers, since it comes closest to being
transitional between the two genera.
Anceyodonta andersoni, new species (Cooke &
Solem). Figure 82e, f.
Diagnosis. — Shell of average size, diameter 2.96-3.62 mm. (mean
3.29 mm.), with 5V4-6 normally coiled whorls. Apex and spire
moderately and evenly elevated, last whorl descending more rapidly,
H/D ratio 0.547-0.625 (mean 0.570). Umbilicus widely open, V-
shaped, later whorls derailing more rapidly, contained 2.95-3.96 times
(mean 3.34) in the diameter. Postnuclear whorls with high,
prominent, slightly protractively sinuated radial ribs, 61-96 (mean
79.0) on the body whorl, whose interstices are 2 - 3 times their width.
Microsculpture a lattice of very fine radial riblets crossed by slightly
finer and more crowded spiral riblets, plus prominent secondary
spiral cords. Sutures deep, whorls strongly rounded. Aperture ovate,
inclined about 10° from shell axis. Parietal barriers 4, extending more
than one-quarter whorl, usually with a recessed, threadlike trace
above upper parietal: upper high and bladelike, gradually descending
over anterior fourth, posterior two-thirds with downward pointing
bifid section, joined with top of regular section by a heavy callus
pad; 2nd with posterior visible half equal in height to 1st, weakly
expanded posteriorly, with anterior third threadlike; 3rd same as
2nd, except posterior elevated portion a little shorter and with more
gradual anterior descension; 4th with same form as 2nd, but greatly
reduced in height posteriorly. Columellar wall with a low, recessed,
threadlike ridge, lying parallel to plane of coiling, rarely (14.2 per
cent) with a 2nd columellar barrier above. Palatal barriers 4,
extending beyond line of vision, with three to five accessory traces:
lower high and bladelike, with rather sharp anterior descension; 2nd
slightly higher with more gradual anterior descension; 3rd more
broadly expanded above, equal in height to 2nd; 4th a lower
bladelike ridge, only weakly expanded above, with abrupt anterior
descension, situated opposite 1st parietal. Accessory traces between
1st and 2nd plus 2nd and 3rd palatals are prominent threadlike
ridges, extending to anterior palatal barrier margins; two smaller and
rather inconspicuous recessed threadlike traces usually located above
4th palatal; and often a broad, low inconspicuous recessed trace
located between columellar and 1st palatal.
The widely open umbilicus and relatively low
spire of Anceyodonta andersoni immediately separate
it from all species of Anceyodonta except A. alternata
and A. soror. The former has a depressed apex,
extremely wide umbilicus, alternating high and low
ribbing and is much smaller (diameter 2.24 mm.). A.
soror has 5 parietals, the columellar barrier deflected
onto the basal lip, and is generally much smaller
(mean diameter 2.61 mm.), while A. andersoni has 4
parietals, the columellar barrier parallel to the plane
of coiling, and is generally much larger (mean diameter
3.29 mm.).
Description. — Shell of average size, with 5'4 normally coiled
whorls. Apex and spire moderately and evenly elevated, last whorl
descending more rapidly, H/D ratio 0.550. Apical whorls 1%,
sculpture eroded. Postnuclear whorls with prominent, high, slightly
protractively sinuated radial ribs, 77 on the body whorl, whose
interstices are 2-3 times their width. Microsculpture of numerous
very fine radial riblets, eight to twelve between each pair of major
ribs, crossed by even finer spiral riblets, plus a secondary sculpture of
prominent spiral cords. Sutures deep, whorls strongly rounded,
slightly flattened above and below periphery. Color mostly leached
from shell, a few irregular, reddish flammulations remaining.
Umbilicus broadly open, V-shaped, last whorls decoiling more
rapidly, contained 3.45 times in the diameter. Aperture ovate,
compressed laterally above and below periphery, inclined about 10°
from shell axis. Parietal barriers 4, extending at least one-quarter
whorl, well beyond line of vision: upper a high lamellar blade,
becoming bifidly flattened above posteriorly, bifid portion hooked
sharply downward; 2nd and 3rd with threadlike anterior third,
becoming high lamellae posteriorly, slightly expanded above and
turned moderately downward; 4th with threadlike anterior portion,
becoming less high and lamellate posteriorly. Columellar barrier a
low, deeply recessed thread lying parallel to the plane of coiling with
a vague accessory lump at the umbilical-parietal margin. Palatal
barriers 4, with four additional traces, extending beyond line of
vision: lower three high and lamellate, rather expanded on top, the
bottom one slightly lower than the next two, all gradually
descending anteriorly to lip margin; upper palatal a thin lamellar
ridge lying opposite the upper parietal tooth and abruptly descending
anteriorly, much lower than 3rd palatal. Palatal traces lying between
the columellar and bottom palatal, 1st and 2nd palatal, 2nd and 3rd
palatal and above the upper palatal. Of these, the trace between the
1st and 2nd palatal is by far the largest. Height of holotype 1.81
mm., diameter 3.29 mm.
Holotype. — Gambier Islands: Mangareva, Station
142, Mangareva Islet, inland from Ganhutu. Collected
by Y. Kondo and C. M. Cooke, Jr. on June 3, 1934.
BPBM 138936.
Range. — Mangareva Islet, Mangareva, Gambier
Islands.
Paratypes. — Same as list of material.
Material. — Mangareva: Mangareva Islet, vicinity
of Ganhutu (Stations 142, 277) on flat land (18
specimens, BPBM 138936, BPBM 138964); vicinity of
Rikitea (Stations 187, 189) in gardens and on flat land
(5 specimens, BPBM 141660, BPBM 141686-7);
northeast of Vaituatai Bay (Station 197) on flat land
(2 specimens, BPBM 139009).
192
SOLEM: ENDODONTOID LAND SNAILS
Remarks. - The holotype is unusual in lacking
the minor parietal trace and in having a weak 2nd
columellar barrier. Only two of 14 adults had the
additional columellar. Although the low spire and wide
umbilicus give a quite different appearance to A.
andersoni, the great majority of the shell features
conform to the Anceyodonta pattern (table LXVIII).
Similar changes in growth pattern followed by greatly
increased size probably provided the means for
Gambiodonta to evolve from Anceyodonta.
Great pleasure is taken in naming this species
after Donald Anderson, malacological assistant on the
Mangarevan Expedition.
Anceyodonta alternata, new species (Cooke &
Solem). Figure 82c-d.
Diagnosis. — Shell very small, diameter 2.24 mm., with 4Vi
planulately coiled whorls. Apex and spire depressed below level of
body whorl, H/D ratio 0.456. Umbilicus broadly V-shaped, regularly
decoiling, contained 2.72 times in the diameter. Postnuclear whorls
with an alternation of major and minor slightly protractively
sinuated radial ribs, 48 on the body whorl, whose interstices are
about 2-3 times their width. Microsculpture of fine radial riblets, six
to eight between each pair of major ribs, crossing very fine and
crowded spiral riblets, with a secondary sculpture of low, rounded
spiral cords. Sutures deep, whorls strongly rounded, flattened
laterally. Aperture flatly ovate, inclined about 5° from shell axis.
Parietal barriers 4, extending beyond line of vision, with one
accessory trace, as in Anceyodonta andersoni, except lower parietal
less reduced in height. Columellar and palatal barriers as in
andersoni.
The depressed spire, very wide umbilicus, and
striking alternation of large and small major ribs
immediately separate Anceyodonta alternata from the
other Anceyodonta.
Description. — Shell small, with slightly more than 4 '4
planulately coiled whorls. Apex and spire depressed, body whorl
strongly rounded above and below with flattened sides, H/D ratio
0.456. Embryonic whorls I1* with faint traces of microradial ribbing
remaining. Lower whorls with pairs of larger and smaller radial ribs,
the larger twice the height of the smaller and separated from it
by the width of the smaller. Each pair is then separated by about the
width of the larger from the next pair. Microsculpture of six to eight
radial riblets between each pair of major ribs. Microradial riblets
crossing low, rounded spiral cords on the mid-sections of the whorls
and the basal portion, and barely visible crowded spiral riblets.
Sutures moderately impressed, whorls rounded above, flattened
laterally. Umbilicus widely opened, contained 2.72 times in the
diameter, with slightly shouldered margins. Aperture ovate, strongly-
rounded above and below, inclined about 5° from shell axis. Parietal
barriers 4, extending past the line of vision: lower 3 with visible
anterior third low and threadlike, becoming lamellate and slightly
expanded above posteriorly; upper parietal with much shorter
anterior portion becoming quite high and lamellate with a sharply
downwardly hooked lamellate bifidity posteriorly. Between the
upper parietal and the lip margin is a slender accessory ridge.
Columellar barrier a threadlike ridge, parallel to plane of coiling,
extending partway across columellar callus. Deeply recessed within
the aperture is a trace of a 2nd columellar barrier located above the
one shown in the type figure. Major palatal barriers 4, with six
accessory traces: first 3 bladelike, expanded and serrated above with
gradual anterior descension; 1st palatal equal in size to 2nd; upper
palatal more nearly ridgelike. with quite sharp anterior descension.
Accessory palatal traces located between major palatals 1 and 2, 2
and 3 and above 4 are quite prominent with the ones on the upper
lip margin, between palatals 3 and 4 and between the columellar and
1st palatal barrier, relatively small and insignificant. Height of
holotype 1.02 mm., diameter 2.24 mm.
Holotype. — Gambier Islands: Mangareva, Man-
gareva Islet, Station 187, north part of Rikitea.
Collected on open ground by Yoshio Kondo on June 7,
1934. BPBM 141661.
Remarks. — The single specimen cannot be
mistaken for any other Mangarevan shell. The unique
double ribbing of alternating large and small radial
ribs and depressed spire combine with the very widely
open umbilicus and downwardly hooked bifid upper
parietal barrier to distinguish A. alternata. Anceyo-
donta andersoni, also from Mangareva Islet, has
essentially identical apertural barriers, differing only
in having the 4th parietal much reduced in height and
the 2nd columellar and lowest palatal trace less deeply
recessed.
Possibly A. alternata may be based on a teratolog-
ical juvenile individual of A. andersoni, but the
differences are so gross that I consider this unlikely.
There is no trace of repaired damage on the specimen.
If the alternating ribbing was not present, I would be
less certain of its distinctiveness.
Anceyodonta difficilis, new species. Figure 83a, b.
Diagnosis. — Shell of average size, diameter 2.57-3.49 mm. (mean
2.93 mm.), with 6-7V4 tightly coiled whorls. Apex and spire strongly
elevated, usually rounded above, H/D ratio 0.651-0.762 (mean 0.711).
Umbilicus very small to minute or barely perforate, contained 8.27-
40.0 times (mean 19.1) in the diameter. Postnuclear sculpture of
narrow, prominent, slightly protractively sinuated radial ribs, 53-84
(mean 68.8) on the body whorl, whose interstices are 2-4 times their
width. Microsculpture of fine radial riblets, five to eight between
each pail' of major ribs, crossed by finer and much more crowded
spiral riblets, with a secondary sculpture of low, rounded, prominent
spiral cords. Sutures shallow, whorls slightly compressed laterally
and on basal margin, a narrow prominent subsutural sulcus present.
Aperture ovate, slightly compressed laterally and on basal margin, a
narrow prominent subsutural sulcus present. Aperture ovate, slightly
compressed laterally and on basal margin, inclined about 5° from
shell axis. Parietal barriers 4 or 5, extending more than one-quarter
whorl: upper parietal a high bladelike ridge, with gradual anterior
descension, posteriorly bulbously expanded and serrated, deflecting
downward laterally; 2nd parietal a low indistinct, threadlike ridge,
absent or very reduced in most specimens; 3rd and 5th parietals with
anterior visible two-thirds low and threadlike, becoming abruptly
elevated, expanded and serrated posteriorly; 4th parietal a low and
threadlike ridge for entire length. Columellar barrier a high bladelike
ridge, deflected down onto basal margin, with sharp anterior
descension to left margin, followed by a sinuated rise to flattened
bladelike portion. Palatal barriers 4, extending one-quarter whorl,
high and bladelike, with three to six accessory traces: lower palatal
greatly reduced in height, a low ridge; 2nd and 3rd palatals high,
similar in descension to columellar; 4th palatal a lower, V-shaped
ridge, lying opposite 1st parietal. Accessory palatal traces lying
between 1st and 2nd, 2nd and 3rd, rarely between 3rd and 4th, with
two or three traces present above 4th palatal.
The quite small umbilicus is the most obvious
character separating Anceyodonta difficilis from A.
soror, which is found at the same localities. The
former also is much more elevated. Some specimens of
A. difficilis may be confused with A. obesa, but the
FIG. 83. a-b, Anceyodonta difficilis, new species. Station 189, Rikitea, Mangareva Islet, Mangareva, Gambier Islands. Holotype. BPBM
141686; c-g, Anceyodonta soror, new species, c-e. Station 277, Ganhutu, Mangareva Islet, Mangareva,. Gambier Islands. Holotype. BPBM
138965; f-g, Station 189. Rikitea, Mangareva Islet, Mangareva, Gambier Islands. Paratype. BPBM 9657. Scale lines equal 1 mm. Drawings by
YK reproduced through the courtesy of Bernice P. Bishop Museum.
193
194
SOLEM: ENDODONTOID LAND SNAILS
2.63
2.37
2.10
1.84
1.58
D
soror
difficilis
_L
J_
_L
2.30
2.50
3.09
3.29
2.70 2.90
Diameter in mm.
FIG. 84. Scatter diagram showing relationship for height to diameter in Anceyodonta soror and A. difficilis.
3.49
latter can easily be distinguished by having the
columellar barrier on the columellar wall or at most
slanting downward across the columellar callus, while
in A. difficilis it is on the basal margin.
Description. — Shell a little larger than average, with 6%
relatively tightly coiled whorls. Spire markedly elevated, with apex
slightly rounded, last whorl not descending more rapidly, H/D ratio
0.660. Embryonic whorls 1%, sculpture eroded. Postnuclear whorls
with broad, prominent, slightly protractively sinuated radial ribs, 84
on the body whorl, whose interstices are 2 - 6 times their width.
Microsculpture of numerous fine radial riblets, crossed by much finer
and more crowded spiral riblets, with a secondary sculpture of strong
spiral cords. Sutures shallow, whorls slightly flattened above, with
prominent sulcus below suture. Umbilicus constricted internally, last
whorl decoiling, narrowly open, contained 8.27 times in the diameter.
Color absent, except for faint remnants of reddish flammulation.
Aperture constricted with evenly rounded outer margin and slightly
flattened base. Parietal barriers 4, extending past line of vision:
upper a narrow, high lamella with sharp anterior descension,
pointing toward upper palatal tooth; 2nd and 4th palatals with
visible anterior two-thirds a low thread, posteriorly becoming
moderately high and almost bulbously expanded above; 3rd parietal
a threadlike trace for its entire length. Columellar barrier higher
than parietals, displaced onto basal lip and reaching apertural
margin. Major palatals 4, extending about one-quarter whorl: basal
a low ridge; 2nd and 3rd moderately high and lamellate, expanded
and serrated above with gradual anterior descension; 4th a low, V-
shaped ridge with sharp anterior descension, lying opposite the upper
parietal. Palatal traces present between palatals 1 and 2, 2 and 3
very large, almost equal in size to 1st palatal; other three traces
above upper palatal tooth small and threadlike. All palatal barriers
and traces reaching edge of apertural callus. Height of holotype 1.98
mm., diameter 2.99 mm.
Holotype. - Gambier Islands: Mangareva, Station
189, Mangareva Islet, north end of Rikitea. Collected
on open ground by C. M. Cooke, Jr. and Y. Kondo on
June 8, 1934. BPBM 141686.
Range. — Mangareva Islet, Mangareva, Gambier
Islands.
Paratypes. — Same as list of material.
Material. — Mangareva: Mangareva Islet (Sta-
tions 142, 277) vicinity of Ganhutu, on open ground (6
specimens, BPBM 9636, BPBM 9642); Mangareva Islet
(Stations 187, 189) north end of Rikitea on open
ground (19 specimens, BPBM 141668, BPBM 141688);
Mangareva Islet, Rikitea (1 specimen, BPBM 9646).
Remarks. — In only two of the 26 specimens was
the subsutural sulcus absent. Most shells showed a
broad white area between the upper and second
parietal that in three shells had become a recognizable
5th parietal barrier. The holotype is a relatively
depressed individual with comparatively wide umbil-
icus, but is in better condition than most other
specimens.
SYSTEMATIC REVIEW
195
.770
.730
.690
650
.610
D
•
n
n
soror
difficilis
I
10
15
20
DIU Ratio
25
30
35
40
FIG. 85. Scatter diagram showing relationship of H/D ratio to D/U ratio in Anceyodonta soror and A. difficilis.
While the differences in parietal barriers and
umbilical size at once separate A. soror from A.
difficilis, there are subtle differences in relative height
and size that are equally significant. Scatter diagrams
of the height and diameter (fig. 84) and H/D and D/U
ratios (fig. 85) show that, despite moderate overlap,
there are distinct differences in size and proportions.
Calculation of regression lines for the height and
diameter by Bartlett's method yielded lines that
diverge insignificantly, although being quite separated
on the diagram. The differences in H/D and D/U
ratios are much more dramatic, although even here
there is some overlap for an individual character.
Similar charts were prepared for the A. obesa - A.
densicostata pair, but are not published because these
two species have more obvious differentiating features.
Anceyodonta soror, new species. Figure 83c-g.
Diagnosis. - Shell slightly smaller than average, diameter 2.24-
3.09 mm. (mean 2.61 mm.), with 5 to 6'/6 normally coiled whorls.
Apex and spire moderately and evenly elevated, slightly rounded
above, last whorl not descending more rapidly, H/D ratio 0.592-0.677
(mean 0.628). Umbilicus widely open, narrowed internally, last whorl
decoiling more rapidly, contained 2.96-4.80 times (mean 4.25) in the
diameter. Postnuclear sculpture of prominent, narrow, slightly
protractively sinuated radial ribs, 53-74 (mean 65.0) on the body
whorl, whose interstices are 2-3 times their width. Microsculpture of
fine radial riblets, five to eight between each pair of major ribs,
crossed by much finer and more crowded spiral riblets, with a
secondary sculpture of low, rather widely spaced spiral cords that are
most prominent on shell base. Sutures impressed, whorls strongly
rounded above, slightly compressed laterally and on basal margin,
very slight indication of a subsutural sulcus. Aperture ovate, slightly
compressed laterally, inclined a little more than 5° from shell axis.
Parietal barriers 5, extending more than one-quarter whorl, numbers
2 and 4 reduced, with a single superior parietal trace: upper high and
lamellate, posteriorly expanded and serrated above, with gradual
anterior descension; 2nd a faint threadlike trace for entire length;
3rd and 5th parietals with anterior visible two-thirds threadlike,
posteriorly elevated, expanded and serrated above, slightly lower
than 1st parietal; 4th parietal a prominent threadlike trace,
expanded and serrated on top, equal in height to threadlike portions
of 3rd and 5th parietals. Parietal trace situated above upper parietal,
about one-third of way to parietal-palatal margin. Columellar
barrier very large, twisted downward onto basal margin, with
sinuated anterior descension. Major palatal barriers 4, with four to
six accessory traces: lower palatal greatly reduced in height, scarcely
larger than first palatal trace; 2nd and 3rd palatals similar in height
and structure to columellar, extending posteriorly beyond line of
vision; 4th palatal a low V-shaped ridge, lying opposite 1st parietal,
equal in height to 1st palatal. Palatal traces large, reduced in size
from bottom to top, present between 1st and 2nd, 2nd and 3rd, and
two present above 4th palatal. Some specimens have a second trace
present between palatals 2 and 3, plus a sixth trace between palatals
3 and 4. Rarely a second trace between 3rd and 4th, with two or
three traces present above 4th palatal.
196
SOLEM: ENDODONTOID LAND SNAILS
The widely open umbilicus is the most obvious
character separating Anceyodonta soror from A.
difficilis. A. soror generally is smaller, less elevated
and invariably has the 5th parietal present, while in A.
difficilis there may be only 4 parietals.
Description. - Shell relatively small, with 5!/2 loosely coiled
whorls. Apex and spire distinctly elevated, last whorl not descending
more rapidly, H/D ratio 0.624. Apical whorls 1%, sculpture eroded.
Postnuclear whorls with low, relatively wide, somewhat protractively
sinuated radial ribs, 61 on the body whorl, whose interstices are 2-4
times their width. Microsculpture of eight to twelve radial riblets
between each pair of major ribs, with a secondary sculpture of
indistinct, low, broadly rounded spiral cords. Sutures shallow, whorls
relatively flattened above with very slight subsutural sulcus, body
whorl very slightly flattened laterally. Umbilicus narrowly open
internally, 1st whorl decoiling rapidly, contained 3.85 times in the
diameter. Aperture ovate, slightly compressed laterally and on basal
margin, inclined less than 10° from shell axis. Parietal barriers 5,
with one superior threadlike trace: upper high and bladelike,
extending beyond the line of vision, thickened on lower edge and
hooked downward with the thickened portion flattened, anterior
descension gradual with very short threadlike portion; 2nd parietal a
low threadlike ridge narrowly flattened above and serrated
posteriorly, anterior visible third threadlike; 3rd parietal threadlike
for anterior visible two-thirds, becoming high and bulbously
expanded with minute serrations on posterior third, which is partly
deflected down; 4th parietal a low threadlike ridge slightly higher
and wider than 2nd, minutely serrated posteriorly; 5th parietal
threadlike for anterior two-thirds, becoming bulbously expanded and
serrated posteriorly, but smaller in size than 3rd parietal. Columellar
barrier high, roundly expanded and serrated posteriorly, twisting
parallel to shell axis, displaced onto basal lip and gradually
descending across callus almost to apertural margin. Outer margin of
columellar barrier flattened and serrated, inner rounded above.
Apertural callus relatively low and wide. Palatal barriers 4,
extending posteriorly almost one-quarter whorl, with six accessory
traces: lower palatal greatly reduced in height, an elevated ridge,
flattened above and sharply descending onto apertural margin; 2nd
palatal high, broadly expanded above, with minute serrations; 3rd
palatal somewhat lower, bulbously expanded above with minute
serrations, gradually descending anteriorly; 4th palatal a V-shaped
ridge situated opposite upper parietal, sharply descending to the
apertural callus. Two low, threadlike palatal traces located above
the upper palatal; one between palatals 3 and 4; two between
palatals 2 and 3; and one between palatals 1 and 2: lower two
palatal traces are the largest, the lowest almost equal in size to lower
palatal. Height of holotype 1.58 mm., diameter 2.54 mm.
Holotype. — Gambier Islands: Mangareva, Station
277, Ganhutu, northeast end of Mangareva Islet.
Collected on open ground by Donald Anderson on
June 26, 1934. BPBM 138965.
Range. — Mangareva Islet, Mangareva, Gambier
Islands.
Paratypes. — Same as list of material.
Material. - • Mangareva: Mangareva Islet (Sta-
tions 139, 142, 277) vicinity of Ganhutu on open
ground (14 specimens, BPBM 138937, BPBM 138965,
BPBM 141270); Mangareva Islet (Stations 155, 189),
vicinity of Rikitea on open ground (4 specimens,
BPBM 9657, BPBM 9679, BPBM 139001).
Remarks. - The number of palatal traces is
variable in Anceyodonta soror, with only a few
specimens having six, most possessing five. One
gerontic individual from Rikitea (BPBM 9657) had the
barriers somewhat reduced (fig. 83g), very widely
spaced ribbing (53 on the body whorl), and the
umbilicus narrower (contained 7.83 times in the
diameter) than the other shells. Also the columellar
barrier is only partly displaced from the columellar lip.
Similar gerontic specimens are known in Minidonta
simulata and A. subconica, so that this variation is
not considered to be significant.
The wider opening of the umbilicus in A. soror is
caused by rapid decoiling during the last whorl of
growth, and thus differs greatly in form from the wide
openings found in A. andersoni and A. alternata. The
latter two have the more typical umbilical decoiling,
while the umbilicus in A. soror is a modification of the
typical Minidonta- Anceyodonta pattern.
Anceyodonta sexlamellata (Pfeiffer, 1845). Fig-
ure 86a-e.
Helix sexlamellata Pfeiffer, 1845, Zeits. Malak., 2, p. 85-Gambier
Islands; Pfeiffer, 1848, Monog. helic. viv., 1, p. 186; Pfeiffer,
1852, Syst. Conchyl., Cab., I 12, (2), p. 200, pi. 100, figs. 44-48
(plate issued in 1850); Pfeiffer, 1853, Monog. helic. viv., 3, p. 144;
Pfeiffer, 1859, toe. cit., 4, p. 155; Pfeiffer, 1869, toe. cit., 5, p. 221;
Pfeiffer, 1876, toe. cit., 7, p. 259.
Pitys sexlamellata (Pfeiffer), Pease, 1871, Proc. Zool. Soc. London,
1871, p. 474— Mangareva, Gambier Islands; Ancey, 1889, Le
Naturaliste, 3, p. 118.
Helix (Endodonta) sexlamellata (Pfeiffer), Tryon, 1887, Man.
Conchol., (2), 3, p. 63, pi. 12, figs. 11-13 (copied from Syst.
Conchyl. Cab.).
Patula (Endodonta) perarmata Smith, 1892, Conchologist, 2, (7),
p. 165, figs.-St. Helena (error).
Endodonta (Thaumatodon) sexlamellata (Pfeiffer), Pilsbry, 1893,
Man. Conchol., (2), 9, p. 17.
Diagnosis. — Shell slightly larger than average, diameter 2.44-
3.59 mm. (mean 2.99 mm.), with 5'/4-7Vi moderately tightly to very
tightly coiled whorls. Apex and spire normally very strongly
elevated, slightly rounded above, last whorl not descending more
rapidly, H/D ratio 0.634-0.929 (mean 0.743). Umbilicus minute,
occasionally moderately open, contained 6.93-29.6 times (mean 15.1)
in the diameter. Postnuclear sculpture of prominent, narrow to
broad, very slightly protractively sinuated radial ribs, 60-125 (mean
89.6) on the body whorl, whose interstices are usually less than twice
their width. Microsculpture of very fine radial riblets, seven to
twelve between each pair of major ribs, crossed by barely visible,
extremely crowded spiral riblets, many specimens with a secondary
sculpture of low rounded spiral cords. Sutures impressed, whorls
strongly rounded above, somewhat compressed on basal margin, with
inward extension of columellar wall, normally with a weak to very
strong supraperipheral sulcus, many examples with a subsutural
sulcus also present. Aperture ovate, strongly inwardly extended
basally, inclined less than 5° from shell axis. Parietal barriers 3,
extending more than one-quarter whorl posteriorly, usually with
three to five accessory traces: upper parietal high and bladelike,
expanded and serrated above on posterior two-thirds, with very
gradual anterior descension; 2nd parietal with posterior visible half
elevated slightly higher than 1st parietal, very broadly expanded and
serrated above, anterior visible third low and threadlike; 3rd parietal
identical in structure to 2nd, except less broadly expanded above
posteriorly. Accessory parietal traces: two between upper parietal
and parietal-palatal margin, with second less conspicuous; between
1st and 2nd parietal; between 2nd and 3rd parietal; below 3rd
parietal. All parietal traces deeply recessed and inconspicuous,
intraparietal traces often reduced or absent. Columellar barriers 2,
high and bladelike. 2nd slightly lower, gradually descending across
inward edge of very thick columellar callus. Palatal barriers 4,
extending almost one-quarter whorl, with six to eleven accessory
SYSTEMATIC REVIEW
197
FIG. 86. Anceyodonta sexlamellata (Pfeiffer): a-b, Gambler Islands. BPBM 106237 ex W. F. Webb, Gude; c-d, Station 187, Rikitea,
Mangareva Islet, Mangareva, Gambler Islands. BPBM 141666; c, Station 197, Vaituatai Bay, Mangareva Islet, Mangareva, Gambler Islands.
BPBM 139012. Scale lines equal 1 mm. Figures d and e greatly enlarged. Drawings by YK reproduced through the courtesy of Bernice P. Bishop
Museum.
traces: lower palatal very slightly lower than 2nd, high and bladelike,
expanded and serrated above posteriorly, with gradual anterior
descension to middle of columellar basal callus; 2nd and 3rd palatals
slightly higher, equally expanded and serrated above, with longer
and more gradual descension, slightly more deeply recessed within
aperture; 4th palatal reduced in height, a relatively high, V-shaped
ridge lying opposite upper parietal. Palatal traces normally dis-
tributed as follows: three above upper palatal; two between 3rd and
4th palatal; three between 2nd and 3rd palatal; and three between
1st and 2nd palatal. Of the palatal traces between the lower 3
barriers, the central of each trio normally is largest. Reduction of
palatal traces normally involves the smaller ones between the lower
barriers and one or two of the smaller traces above upper palatal.
The 2 slanted columellar barriers, only 3 elevated
parietals, very high spire, large number of palatal and
parietal traces, plus the presence of a supraperipheral
sulcus in many specimens separate A. sexlamellata
from the other Anceyodonta. The only other species
that have 3 parietals, even occasionally, are minute (A.
ganhutuensis) or differ greatly in their barrier length
and number of palatal traces and are very large (A.
labiosa and A. hamyana). A. obesa and A. densicos-
tata normally have 5 parietals and rarely have only 3.
Description. — Shell relatively large, with slightly more than 6%
tightly coiled whorls. Apex and spire strongly elevated, rounded
above, last whorl descending a little more rapidly, H/D ratio 0.753.
Apical whorls V/i, sculpture of prominent, moderately widely spaced
radial ribs with a microsculpture of two or three radial riblets
between each pair of major ribs and a barely visible faint spiral
microsculpture. Postnucleat whorls with prominent, broadly
rounded, sinuately protractive radial ribs, 87 on the body whorl,
whose interstices are less than 3 times their width. Microsculpture a
198
SOLEM: ENDODONTOID LAND SNAILS
lattice of prominent, somewhat irregular radial riblets crossed by
barely visible, much more crowded spiral riblets. Sutures deep,
whorls somewhat shouldered above moderately prominent subsutural
sulcus, basal margin elongated and flattened. Umbilicus minute,
barely perforate, contained 24.3 times in the diameter. Color light
yellowish horn with narrow to broad, irregularly spaced zigzag radial
streaks more or less coalescing on base of shell. Aperture elongately
ovate with flattened basal margin and fairly prominent subsutural
sulcus, lip badly broken. Parietal barriers 3, extending slightly more
than one-quarter whorl: upper parietal high, ridgelike, broadly
rounded above with gradual anterior descension, posterior two-thirds
minutely barbed on top and sides; 2nd parietal higher, less broadly
rounded, with anterior quarter low, smooth, threadlike, becoming
slightly higher posteriorly with coarser, more prominent barbing; 3rd
parietal intermediate in height and breadth, anterior third very low
and threadlike, somewhat less prominently barbed above posteriorly.
Columellar and basal margins with heavy callus, occupying on
columellar wall almost one-fourth width of aperture. Columellar
barriers 2: upper a narrow, smooth ridge parallel to the plane of
coiling and reaching just across inner face of callus; lower a much
smaller threadlike ridge, slightly recessed and less prominent. Palatal
barriers 4, extending nearly one-quarter whorl, with eleven accessory
traces: lower palatal basal in position, an inconspicuous ridge with
gradual anterior descension, partially affected by heavy callus; 2nd
palatal near palatal-basal margin, a high lamellar ridge with gradual
anterior descension, posterior two-thirds minutely barbed above and
on sides; 3rd palatal opposite middle parietal, equal in height to 2nd
but with slightly sharper anterior descension, relatively broadly
rounded above with minute serrations extending to anterior quarter;
upper palatal situated opposite 1st parietal, a lower, ridgelike barrier
slightly expanded above with fine serrations present over most of
length and relatively sharp anterior descension. Palatal traces low,
all relatively inconspicuous, located as follows: three between 1st
and 2nd palatals; three between 2nd and 3rd palatals; two between
3rd and 4th palatals, and three between upper palatal and the
palatal-parietal margin. Height of lectotype 2.40 mm., diameter 3.19
mm.
Lectotype. — Gambler Islands. Collector unknown.
BMNH 1962702/1 (ex-Hugh Cuming).
Range. — Agakauitai, Akamaru, Aukena, Man-
gareva and Taravai Islets, Mangareva, Gambier Is-
lands.
Paratypes. — Gambier Islands (7 specimens,
BMNH 1962702/2-8).
Material. — Gambier Islands (9 specimens, BPBM
106237, BMNH 1962702/1-8): Mangareva (27 speci-
mens, BPBM 167414, BPBM 115402, FMNH 46445);
Mangareva Islet, north end (Stations 155, 187, 189)
and gardens of Rikitea (31 specimens, BPBM 9675,
BPBM 9705, BPBM 139003, BPBM 141666, BPBM
141691); Mangareva Islet, northeast (Station 197) of
Vaituatai Bay (5 specimens, BPBM 139012); Mang-
areva Islet, vicinity (Stations 139, 277) of Ganhutu (8
specimens, BPBM 138977, BPBM 141271); Aukena
Islet, along trail near gap and caves (Stations 88, 102,
103) east of gap (257 specimens, BPBM 9661, BPBM
138704, BPBM 138754, BPBM 138756, BPBM 138796);
Aukena Islet, west (Stations 79, 82, 92) end (8
specimens, BPBM 138667, BPBM 140841, BPBM
140853); Aukena Islet, north (Station 104) side (1
specimen, BPBM 138815); Akamaru Islet, in wave
(Station 107) cutting (190 specimens, BPBM 138850);
Akamaru Islet, northwest (Station 97) side (18
specimens, BPBM 138826, BPBM 138828); Agakauitai
Islet, northwest (Station 195) side (47 specimens,
BPBM 9672, BPBM 138896, BPBM 138899-900,
BPBM 138902); Taravai Islet, in sand (Station 126)
sweepings (13 specimens, BPBM 138882).
Remarks. — Specimens referable to Anceyodonta
sexlamellata were collected on five islets. Further
study of local variation is needed, since time did not
permit full study of the 613 specimens. In several sets
the umbilical width was not measured and only a few
individuals had rib counts made. Only part of the
adults from Stations 88 and 107 were utilized. There
are obvious differences between populations (table
LXX). Shells from Mangareva are much smaller than
those from the other islets or the original Cuming
material. The sets from Taravai and Agakauitai are
quite depressed and have much wider umbilici than
shells from Aukena and Akamaru. There is consid-
erable variation in ribbing, the contrast between
Aukena shells (Stations 88 and 102) and those from
Akamaru (Station 107) being particularly large. Using
just material available in Chicago, rib variations for
four stations were:
Number of
Station
Mean
Range
SEM
specimens
88
80.3
60-98
4.91
7
102
76.0
62-105
5.71
7
107
97.9
73-125
3.42
20
"Cuming
material"
89.3
75-116
3.54
13
Some of these differences are statistically significant,
but their biological significance is uncertain.
Comparing Stations 102 and 107, with 25 df, "t" =
3.2628, and in comparing the "Cuming" material with
Station 107, with 31 df, "t" = 1.6755. Other
comparisons are less significant: between "Cuming
material" and Station 88, with 18 df, "t" = 1.4946; and
between Stations 88 and 102 there is no difference
(with 12 df, "t" = 0.5689). Subspecific differentiation
of at least the Taravai and Agakauitai shells from
those found on Aukena and Akamaru may be justified
when the material available is fully analyzed, but
without more detailed study I prefer to withhold
nomenclatural recognition.
The most significant variation was seen in the set
from Vaituatai, about 1 mile north of Rikitea,
Mangareva Islet (Station 197). In these shells (fig. 86e)
the parietal barriers are reduced in size; there are no
parietal traces; there is only a single columellar
barrier; only four to six weak accessory palatals; and
the characteristic sulci are reduced to absent. The very
heavy columellar callus and position of the barriers are
the same as in normal shells of A. sexlamellata and
this seems to be only an extreme variant.
More specimens from old collections tended to
have the sulci reduced (fig. 86a) than in material from
the Mangarevan Expedition, but such small numbers
are involved that sampling error may be responsible
rather than morphological change. The prominence of
the sulci is a highly variable character.
SYSTEMATIC REVIEW
199
Description of Patula (Endodonta) perarmata
Smith (1893, p. 165, figs.) from "St. Helena" is a
matter of mislabelled specimens. The tablet on which
the specimens were pasted contained one example of
the European Discus rotundatus (Muller, 1774) and
two specimens of Anceyodonta sexlamellata. I have
selected the upper of the two specimens figured by
Smith (loc. cit.) as lectotype and thus Patula
perarmata Smith, 1893 becomes a synonym of Anceyo-
donta sexlamellata. I am not prepared to guess as to
which islet the type material of perarmata came from
and doubt that this name should be used for any
eventually recognized subspecies in view of the
complete absence of locality data.
Anceyodonta densicostata, new species (Cooke &
Solem). Figure 87a-b.
Diagnosis. — Shell slightly larger than average, diameter 2.73-
3.19 mm. (mean 3.00 mm.), with 5%-6% relatively tightly coiled
whorls. Apex and spire strongly elevated, rounded above, last whorl
not descending more rapidly, H/D ratio 0.621-0.778 (mean 0.687).
Umbilicus minute, last whorl barely or not decoiling, contained 6.93-
29.6 times (mean 15.1) in the diameter. Postnuclear sculpture of fine,
narrow, very crowded, protractively sinuated radial ribs, 95-114
(mean 104.4) on the body whorl, whose interstices are 2-4 times their
width. Microsculpture of very fine radial riblets, five to nine between
each pair of major ribs, crossed by much finer and more crowded
spiral riblets. No secondary spiral cording present. Sutures impressed,
whorls strongly rounded above, slightly flattened basally. Aperture
ovate, slightly flattened basally, inclined less than 10° from shell
axis. Parietal barriers usually 5, often (15 per cent) 3, extending
posteriorly beyond line of vision, with (50 per cent) or without (50
per cent) a superior accessory trace: upper parietal high and
bladelike, weakly expanded above, with very gradual anterior
descension; 2nd parietal, when present, a low threadlike trace for
entire length; 3rd and 5th parietals with visible posterior quarter
elevated, expanded and serrated on top, anterior three-quarters low
and threadlike; 4th parietal, when present, low and threadlike for
entire length. Parietal trace, when present, located just below
parietal-palatal margin. Columellar barrier moderately recessed,
elevated posteriorly and expanded above, with sinuated anterior
descension to middle of columellar callus. Palatal barriers 4,
extending slightly more than one-quarter whorl, with four to five
accessory traces present: lower palatal equal in height to columellar,
weakly expanded and serrated above, anterior descension simple; 2nd
and 3rd palatals much higher, more broadly expanded above, with
weakly sinuated anterior descension, reaching almost to left margin;
4th palatal reduced in height, a V-shaped ridge lying opposite 1st
parietal. Palatal traces located between 1st and 2nd, 2nd and 3rd,
3rd and 4th with two traces above 4th palatal. Occasionally trace
between 3rd and 4th palatals greatly reduced or absent.
Anceyodonta densicostata is closely related to A.
obesa, apparently bearing the same relation to it that
A. soror appears to have to A. difficilis. The absence of
a subsutural sulcus, the very fine and crowded ribbing
and the more open umbilicus are the main characters
separating A. densicostata from A. obesa. The former
normally has traces between the lower palatals, while
the latter rarely does. Other species of similar size
either have much more widely open umbilici (A.
andersoni and A. labiosa) or 2 columellar barriers and
many palatal traces (A. sexlamellata).
Description. — Shell larger than average, with 6'/4 relatively
tightly coiled whorls. Spire strongly elevated, rounded above, H/D
ratio 0.677. Embryonic whorls 1%, with traces of microradial
sculpture remaining. Postnuclear whorls with narrow, crowded,
strongly protractively sinuated radial ribs, 95 on the body whorl,
whose interstices are 2-3 times their width. Microsculpture of
extremely fine radial riblets, with traces of much finer and more
crowded spiral riblets. Color light yellowish white with prominent,
irregular, reddish-brown flammulations. Sutures moderately im-
pressed, whorls strongly rounded above, slightly compressed laterally.
Umbilicus minutely open, last whorl barely or not decoiling,
contained 11.6 times in the diameter. Aperture ovate, somewhat
compressed on basal margin, inclined about 10° from shell axis.
Parietal barriers 5, extending posteriorly beyond line of vision, plus a
deeply recessed spiral thread just below the upper parietal margin:
1st parietal high, gradually descending anteriorly, with rounded
upper margin, pointing toward upper palatal; 2nd parietal very low
and threadlike; 3rd parietal with anterior three-sixteenths whorl low
and threadlike, becoming high, broadly expanded and minutely
serrated posteriorly; 4th parietal a broadly rounded very low thread;
5th parietal similar in structure to 3rd with expanded portion and
serrations slightly higher. Parietal trace located just below parietal-
palatal margin. Apertural callus relatively weak, becoming stronger
on columellar wall. Columellar barrier equal in height to 1st palatal,
barely reaching past middle of umbilical callus, slanted slightly
downward. Palatal barriers 4, with five accessory traces, extending
beyond line of vision: 1st palatal moderately elevated with rounded
and serrated top, reaching to middle of apertural callus; 2nd and 3rd
palatals much higher, broadly rounded and minutely serrated on top,
with sinuated anterior descension; 4th palatal a V-shaped ridge,
much lower than 3rd, lying opposite upper parietal. Accessory
palatal traces low and threadlike, located between 1st and 2nd, 2nd
and 3rd, 3rd and 4th and two above 4th palatal. Height of holotype
2.07 mm., diameter 3.06 mm.
Holotype. — Gambier Islands: Mangareva, Station
277, Mangareva Islet, vicinity of Ganhutu. Collected
by Donald Anderson on June 26, 1934. BPBM 138975.
Range. — Mangareva and Taravai Islets, Man-
gareva, Gambier Islands.
Paratypes. — Same as list of material.
Material. — Mangareva: Mangareva Islet (Sta-
tions 142, 277), vicinity of Ganhutu (29 specimens,
BPBM 9637, BPBM 138975); Taravai Islet (Station
126), in sand (1 specimen, BPBM 138883).
Remarks. — There was considerable variation in
the number and prominence of the various parietal
barriers. Of 20 adult or nearly adult specimens, 17 had
5 parietals and three had 3 parietals, with numbers 2
and 4 absent. Ten specimens had an accessory parietal
trace, 10 lacked the trace. Nearly all specimens of
Anceyodonta densicostata were found in fossil deposits
near Ganhutu on Mangareva Islet. Surprisingly
enough, a single specimen was recovered from sand on
Taravai Islet (BPBM 138883). This specimen has a
relatively wide umbilicus, contained 6.9 times in the
diameter, and there are only 3 parietals. Since this
reduction also was observed in Ganhutu shells, it is
not deemed significant.
Specimens of A. obesa and A. densicostata on
Mangareva are extremely similar in size, shape, and
barriers. All individuals could be separated on the
basis of the subsutural sulcus and less crowded
sculpture in A. obesa. It is quite possible stratigraphic
collections would demonstrate that A. densicostata is
a local derivative of A. obesa.
FIG. 87. a-b, Anceyodonta densicostata, new species. Station 277, Ganhutu, Mangareva Islet, Mangareva, Gambier Islands. Holotype.
BPBM 138975; c-f, Anceyodonta labiosa, new species, c-d. Station 88, Aukena Islet, Mangareva, Gambier Islands. Holotype. BPBM 9414; e-f,
Station 88, Aukena Islet, Mangareva, Gambier Islands. Form with 3 parietals. Paratype. BPBM 9413. Scale lines equal 1 mm. Drawings by YK
reproduced through the courtesy of Bernice P. Bishop Museum.
200
SYSTEMATIC REVIEW
201
FlG. 88. Anceyodonta obesa, new species: a-b, Station 88, Aukena Islet, Mangareva, Gambier Islands. Holotype. BPBM 138706; c-d, Station
142, Ganhutu, Mangareva Islet, Mangareva, Gambier Islands. Paratype. BPBM 138941; Palatal traces omitted from figure of holotype. Scale
lines equal 1 mm. Drawings by YK reproduced through the courtesy of Bernice P. Bishop Museum.
Anceyodonta obesa, new species.
89a-f.
Figures 88a-d;
Diagnosis. — Shell larger than average, diameter 2.63-4.01 mm.
(mean 3.14 mm.), with 5%-75/8 normally to rather tightly coiled
whorls. Apex and spire moderately to strongly elevated, normally
rounded above, last whorl not descending more rapidly, H/D ratio
0.561-0.805 (mean 0.715). Umbilicus minute (contained more than 15
times in the diameter) to imperforate, normally closed or too narrow
to measure. Postnuclear sculpture of narrow, widely spaced to
crowded, almost vertically sinuated radial ribs, 47-106 (mean 79.6) on
the body whorl, whose interstices are 2-7 times their width.
Microsculpture of extremely fine radial riblets, four to ten between
each pair of major ribs, crossed by much finer and more crowded
spiral riblets. No secondary spiral cording present. Sutures shallow,
whorls strongly rounded on basal margin, slightly compressed
laterally and basally, a weak to usually prominent subsutural sulcus
present. Aperture ovate, slightly compressed laterally and basally,
inclined about 5° from shell axis. Parietal barriers normally 5, rarely
reduced to 3 in number by loss of 2nd and 4th parietals, occasionally
with one or more accessory parietal traces, extending posteriorly
beyond line of vision: upper parietal high, slender, bladelike, with
gradual descension over anterior visible third; 2nd parietal a low,
often reduced, threadlike trace; 3rd and 5th parietals with anterior
visible two-thirds raised threadlike ridges, posterior portion elevated
to height of 1st parietal, expanded and serrated above on visible
posterior quarter; 4th parietal, when present, a reduced threadlike
trace equal in size to 2nd. Parietal traces, when present, situated
above upper parietal near parietal-palatal margin. Columellar barrier
a prominent, crescentic ridge located on columellar wall, angling
slightly downward across columellar callus, stopping short of lip
margin. Palatal barriers 4, extending about three-sixteenths of a
whorl, with zero to six accessory traces: lower palatal greatly
reduced in height, an elevated threadlike ridge stopping well short of
apertural margin; 2nd and 3rd parietals elevated, weakly expanded
and flattened above posteriorly with very gradual descension over
anterior half, somewhat recessed within aperture; 4th palatal a much
lower V-shaped ridge, less recessed within aperture, lying opposite
upper parietal. Palatal traces highly variable in number, many
specimens with no traces, others with two or three present above 4th
palatal, some with one or two present between various lower
palatals, and a few with large palatal traces present between each
major palatal and three above 4th palatal.
Anceyodonta obesa differs from the generally
much larger A. hamyana in having 5 parietal barriers
(rarely only 3), usually is with a strong subsutural
sulcus and has more closely spaced radial ribs (about
8/mm. in obesa, 6.34/mm. in hamyana). The speci-
mens of A. obesa with accessory palatal traces can
easily be confused with A. difficilis and A. densicos-
tata. In A. difficilis the columellar barrier twists
distinctly onto the basal lip and is removed from the
umbilical wall for the entire line of vision, while A.
obesa has a moderately low columellar ridge that, at
most, slants downward across the umbilical wall
toward the basal lip. A. densicostata lacks a subsutur-
FIG. 89. Anceyodonta ofte.so, new species: a-c, Station 142, Ganhutu, Mangareva Islet, Mangareva, Gambier Islands. Paratype. BPBM
138943; d-f. Station 189, north end of Rikitea, Mangareva Islet, Mangareva, Gambier Islands. Paratype. BPBM 141692. Extreme development of
palatal traces and ribbing. Scale lines equal 1 mm. Drawings by YK reproduced through the courtesy of Bernice P. Bishop Museum.
202
SYSTEMATIC REVIEW
203
al sulcus and averages 11.1 ribs/mm, on the body
whorl.
Description. — Shell quite large with slightly more than 6''4
relatively loosely coiled whorls. Spire and apex strongly elevated,
obtusely rounded above, H/D ratio 0.680. Embryonic whorls 1%,
sculpture eroded. Remaining whorls with relatively wide, protractive-
ly sinuated radial ribs, 78 on the body whorl, whose interstices are 2-
3 times their width. Microsculpture consisting of fine radial riblets,
six to ten between each pair of major ribs, crossed by much finer and
more crowded spiral riblets. Sutures relatively shallow, whorls
somewhat flattened above with a distinct subsutural sulcus.
Umbilicus nearly closed by reflection of columellar lip, contained
25.7 times in the diameter. Aperture compressedly ovate, basal
margin flattened and somewhat flattened subperipheral margin.
Callus extremely heavy on columellar lip, gradually reduced in size
and absent from above periphery of body whorl. Parietal barriers 5,
extending more than one-quarter whorl, with one small superior
trace: upper parietal quite high, bladelike, very slightly rounded
above, with very gradual anterior descension; 2nd parietal a low
threadlike ridge, extending beyond the line of vision; 3rd parietal
threadlike for one-eighth whorl, becoming a high bladelike lamella
posteriorly; 4th parieta) a low, threadlike ridge for its visible length;
5th parietal threadlike for first one-eighth whorl, becoming moder-
ately high and lamellate posteriorly with rounded and slightly
expanded top. Parietal trace located just above upper parietal.
Columellar barrier as high as lower palatal, a broadly rounded ridge
reaching across the columellar callus and twisted slightly
downwards. Palatal barriers 4, extending about three-sixteenths of a
whorl, with three faint accessory traces above the upper palatal:
lower palatal a threadlike raised ridge almost as high as columellar
barrier; 2nd palatal very high and bladelike, slightly expanded above,
gradually descending over anterior third to apertural callus; 3rd
palatal similar in form to 2nd but a little lower in height; 4th palatal
a lower V-shaped ridge opposite the upper parietal with the raised
portion extending nearer the aperture. Height of holotype 2.30 mm.,
diameter 3.39 mm.
Holotype. — Gambler Islands: Mangareva, Station
88, Aukena Islet, along trail near gap. Collected by
Donald Anderson and C. M. Cooke, Jr., on May 28,
1934. BPBM 138706.
Range. — Aukena, Mangareva, Agakauitai, and
Akamaru Islets, Mangareva, Gambier Islands.
Paratypes. — Same as list of material.
Material. — Mangareva: Aukena Islet (Stations
82, 88, 102, 103) in the vicinity of the gap (302
specimens, BPBM 9417, BPBM 9664-7, BPBM 138684,
BPBM 138705-6, BPBM 138755, BPBM 138797);
Mangareva Islet (Stations 105, 142, 277) vicinity of
Ganhutu (65 specimens, BPBM 9634, BPBM 9640-1,
BPBM 9643, BPBM 138941, BPBM 138943, BPBM
138968, BPBM 138970, BPBM 138973-4, BPBM
140993); Mangareva Islet (Station 197) northeast of
Vaituatai Bay (6 specimens, BPBM 9645, BPBM
139014); Mangareva Islet (Stations 155, 156, 187, 189)
vicinity of Rikitea (36 specimens, BPBM 9650, BPBM
9656, BPBM 9658, BPBM 9676, BPBM 9680, BPBM
9704, BPBM 139002, BPBM 139004, BPBM 141407,
BPBM 141667, BPBM 141692-3); Agakauitai Islet
(Station 195), northwest side (4 specimens, BPBM);
Akamaru Islet (Station 97), northwest side (3 speci-
mens, BPBM 138827).
Remarks. — On both Aukena and Mangareva
Islets there is considerable variation in size, shape, and
apertural barriers (table LXX). The frequency of the
variants differs on the two islands. While many
specimens can be sorted into apparently different
forms, intergrading examples were seen and probably
only extreme individual variation is involved.
On Aukena Islet the great majority (210 of 302
specimens) have the form of the holotype (fig. 88a, b)
with either faint traces of accessory palatal traces
above the upper palatal (as in fig. 88c) or, more
commonly, without any such lamellar traces (fig. 88a).
Three specimens (BPBM 9666) have strong accessory
traces developed between the major palatals (as in fig.
89d). A number of individuals approached the size of
the smaller form that was so common on Mangareva
Islet, but most of the remainder were probably
juvenile examples.
On Mangareva Islet, variation is more extensive
and complex. Only a very few (eight of 107) individuals
reach the size of the Aukena examples. These varied
greatly in the number of major and minor parietals.
Most of these larger individuals from Ganhutu (BPBM
138941, Station 142, 1 specimen), Rikitea (BPBM
139002, Station 155, 3 specimens), and Vaituatai
(BPBM 139014, Station 197, 2 specimens) are only
moderately elevated with looser coiling than in the
remaining shells (fig. 88c). The majority of Mangareva
Islet A. obesa were distinctly smaller in size (table
LXX), usually with more closely spaced sculpture (not
the figured example), more tightly coiled whorls, and
with more prominent margining on the suture (fig.
89a). In material of A. obesa from Station 88, there
were 8.2 ribs/mm.; from Stations 142 and 277, there
were 8.8 ribs/mm. The closer spacing of the sculpture
is not reflected in greater number of ribs (table LXX)
since with 24 df, "t" = 0.791 in respect to rib counts
from Stations 142 plus 277 and 88. Generally,
accessory traces were present above the upper palatal
and there were one or two low, broad ridges between
the lower palatal barriers. In eight specimens, however,
the lower ridges had been replaced by accessory traces
between the parietals. Individuals with these charac-
ters could easily be confused with Anceyodonta
difficilis, but can be separated by the characters of the
columellar barrier detailed above under the
"Diagnosis." The size and shape differences between
the Aukena and Mangareva shells are highly sig-
nificant. With 62 df "f = 5.8735 in respect to
diameters and "t" = 3.7280 when comparing H/D
ratios. No nomenclatural recognition seems necessary.
Three specimens from the Rikitea area (Stations
187, 189) had very widely spaced radial ribbing and the
apertural barriers were somewhat modified (fig. 89d-
f). Accessory parietal traces were present, the 1st and
3rd parietals both were bifid posteriorly and the
accessory traces were greatly enlarged in size and
prominence. The differences of the three specimens are
all a matter of degree since intermediates between this
form and typical obesa of Mangareva Islet were seen.
204
SOLEM: ENDODONTOID LAND SNAILS
The few specimens from Akamaru and Agakauitai
are in the same size range as the Aukena examples.
The larger and smaller forms of Mangareva were
found at the same stations with the latter pre-
dominating. A similar situation is found in respect to
A. hamyana, which also has a smaller form associated
with a larger at both Ganhutu and Rikitea. These
variations may represent temporally separated popu-
lations, with the smaller coming from unfavorable
years and the larger from more favorable periods. The
Mangareva shells were mostly found on open ground,
thus probably coming from a series of populations,
while those from single caves on Aukena probably
were from much more homogeneous samples.
Anceyodonta labiosa, new species. Figure 87c-f.
Diagnosis. — Shell quite large, diameter 3.06-4.05 mm. (mean
3.55 mm.), with 6 - 6% tightly coiled whorls. Apex and spire
strongly and almost evenly elevated, slightly rounded, H/D ratio
0.658-0.735 (mean 0.700). Umbilicus open, narrow, almost regularly
decoiling, contained 5.48-9.80 times (mean 7.24) in the diameter.
Postnuclear sculpture of prominent, crowded, almost vertical radial
ribs, 78-100 (mean 91.0) on the body whorl, whose interstices are 2-3
times their width. Microsculpture of very fine radial riblets, six to
ten between each pair of major ribs, crossed by much finer and more
crowded spiral riblets, with a secondary sculpture of low, rather
closely set spiral cords. Sutures shallow, whorls strongly rounded
above and on basal margin, almost evenly rounded on outer margin,
no trace of a subsutural sulcus. Aperture ovate, slightly compressed
laterally, inclined about 5° from shell axis. Parietal barriers 3 (36.4
per cent) or 4 (63.6 per cent), extending slightly less than three-
sixteenths of a whorl, rarely with one or two accessory parietal
traces: upper parietal a high slender blade, weakly expanded and
serrated posteriorly, with gradual descension over anterior third; 2nd
parietal with anterior half low and threadlike, broadly expanded in
mid-section, with posterior crescentic lamellar blade arising from
expanded basal portion, occupying posterior third of tooth; 3rd
parietal identical in structure to 2nd, except posterior elevated
portion shorter and lower; 4th parietal, when present, a low
threadlike trace. Accessory parietal traces rarely present between
2nd and 3rd, 3rd and 4th parietals. Columellar barrier a high
crescentic blade, displaced onto basal margin, descending abruptly to
lip edge. Palatal barriers 4, extending one-eighth whorl, rarely one or
two accessory traces: lower palatal greatly reduced in height, a
raised lamellar ridge; 2nd and 3rd palatals very high, slightly
flattened above, with gradual anterior descension; 4th palatal
reduced in height, a V-shaped ridge, lying opposite 1st parietal.
Palatal traces, when present, either both above 4th palatal, or one
above 4th palatal and the other between 2nd and 3rd palatals.
The general appearance of Anceyodonta labiosa is
very similar to that of A. hamyana, but the descension
of the columellar barrier to the basal lip in A. labiosa
at once separates them. The general lack of any
accessory palatal traces, much larger size and fewer
parietal barriers separate A. labiosa from A. soror and
A. difficilis, the other species with similar columellar
barrier displacement.
Description. — Shell much larger than average, with 6Vi tightly
coiled whorls. Spire very strongly elevated, sides slightly rounded,
H/D ratio 0.735. Embryonic whorls IVs, sculpture eroded. Remaining
whorls with relatively prominent, close set, nearly vertical radial ribs,
84 on the body whorl, whose interstices are 2-3 times their width.
Microsculpture of extremely fine radial riblets, six to ten between
each pair of major ribs, crossed by much finer and more crowded
spiral riblets, with a secondary sculpture of well-defined spiral cords.
Sutures shallow, whorls relatively flattened above, rounded on
periphery and base, no subsutural sulcus present. Umbilicus very
narrow, last whorl decoiling a little more rapidly, contained 9.80
times in the diameter. Color nearly gone from shell, with traces of
reddish flammulations remaining. Aperture ovate, with evenly
rounded outer margin, inclined about 5° from shell axis. Parietal
barriers 4, extending less than three-sixteenths of a whorl, with low
accessory threads between parietals 2 and 3, 3 and 4: 1st parietal
elevated, slender, weakly expanded on top, with gradual anterior
descension; 2nd and 3rd parietals broadly flattened anteriorly with
lamellate posterior position arising medially on the flattened
lamellar plate, expanded and serrated on elevated posterior third;
4th parietal with same structure, but posterior part only slightly
elevated. Columellar barrier short, very high, crescentic, displaced
onto basal lip, reaching apertural margin. Palatal barriers 4, very
high, extending about one-eighth whorl: lower a short threadlike
ridge; 2nd and 3rd very high, almost crescentic; 4th a much lower V-
shaped ridge lying opposite upper parietal. Height of holotype, 2.37
mm., diameter 3.23 mm.
Holotype. — Gambier Islands: Mangareva, Station
88, Aukena Islet, along trail near gap. Collected by
Donald Anderson and C. M. Cooke, Jr., on May 28,
1934. BPBM 9414.
Range. — Aukena and Akamaru Islets, Man-
gareva, Gambier Islands.
Paratypes. — Same as list of material.
Material. — Mangareva: Aukena Islet (Station
88), along trail near gap (25 specimens, BPBM 9413-4);
Akamaru Islet (Station 97), on northwest side (2
specimens, BPBM 138829).
Remarks. — The holotype is a relatively small,
quite high example with two accessory parietal traces,
but it is in the best condition of all snecimens. Of the
27 shells, nine had 3 parietals and 18 had 4. In most
examples, the spiral sculpture is very weak. The
two palatal traces are usually above the 4th palatal,
but a few examples lacked all traces and some had one
above the 4th palatal and one between the 2nd and
3rd.
The large size, short barriers, and relatively
elevated shape are quite distinctive. The displacement
of the columellar barrier onto the basal lip at once
separates A. labiosa from the other large species.
Anceyodonta hamyana (Ancey, 1889). Figure
90a-f.
Pitys hamyana Ancey, 1889, Le Naturaliste, 3, p. 84 - Gambier
Islands; Pilsbry, 1892; Man. Conchol., (2), 8, p. 95.
Endodonta (Thaumatodon) hamyana (Ancey), Pilsbry, 1893, Man.
Conchol., (2), 9, p. 27.
Diagnosis. — Shell very large, diameter 3.09-4.93 mm. (mean 3.98
mm.), with 5V4 - 7 normally coiled whorls. Apex and spire moderately
to strongly elevated, usually rounded above, last whorl not
descending more rapidly, H/D ratio 0.557-0.773 (mean 0.667).
Umbilicus generally barely perforate, rarely moderately open or
completely closed, contained 7.31-64 times (mean 22.2) in the
diameter. Postnuclear sculpture of narrow, prominent, rather closely
set radial ribs, 60-120 (mean 79.3) on the body whorl, whose
interstices are 2-3 times their width. Microsculpture of very fine
radial riblets, five to nine between each pair of major ribs, crossed by
much finer and more crowded spiral riblets. Usually no secondary
spiral cording. Sutures well impressed, whorls strongly rounded
above and on umbilical margin, slightly compressed laterally and
ef
FIG. 90. Anceyodonta hamyana (Ancey): a-b, Station 142, Ganhutu, Mangareva Islet, Mangareva, Gambler Islands. BPBM 1389.38; c-d,
Station 82, Aukena Islet, Mangareva, Gambier Islands, BPBM 138699; e-f, Station 142, Ganhutu. Mangareva Islet, Mangareva, Gambler
Islands. BPBM 138939. Scale lines equal 1 mm. Drawings by YK reproduced through the courtesy of Bernice P. Bishop Museum.
205
206
SOLEM: ENDODONTOID LAND SNAILS
basally, no subsutural sulcus present. Aperture ovate, slightly
compressed laterally and basally. inclined less than 10° from shell
axis. Parietal barriers 3 or 4, extending posteriorly almost one-
quarter whorl, without accessory traces: upper parietal a high
lamellar blade, weakly expanded and serrated posteriorly, with
gradual descension over anterior half; 2nd and 3rd parietals with
anterior third threadlike, posterior portion elevated to height of 1st,
strongly expanded and serrated above on posterior third; 4th parietal
similar in structure to 3rd, with posterior elevated portion slightly
reduced in length and height. Columellar barrier a raised threadlike
ridge, twisting slightly downward partway across columellar callus.
Palatal barriers 4, extending three-sixteenths of a whorl, without
accessory traces present: lower palatal equal in height to 2nd and
3rd, weakly flattened above, with rather gradual descension over
anterior third; 2nd and 3rd parietals less recessed within aperture,
more elongated and flattened above, with more gradual anterior
descension; 4th palatal reduced in height, a V-shaped ridge, lying
opposite 1st parietal. No palatal traces present.
The very large size, only moderately elevated
spire, presence of 3 or 4 parietals, small columellar
callus and barrier, and lack of accessory palatal traces
combine to separate Anceyodonta hamyana from all
other Mangarevan endodontids. A. labiosa differs most
obviously in having the columellar barrier displaced
onto the basal lip. A. obesa is smaller and higher with
generally more crowded sculpture and has (usually) 5
parietals. The 2 columellar barriers, very thick colu-
mellar callus, supraperipheral sulcus, usually very high
spire and numerous accessory palatal traces separate
A. sexlamellata from A. hamyana.
Description. — Shell quite large, with 5% moderately tightly
coiled whorls. Apex and spire moderately and evenly elevated, last
whorl descending a little more rapidly, H/D ratio 0.634. Apical
whorls 1%. sculpture of moderately prominent, slightly protractive
radial ribs with traces of finer radial and spiral ribbing barely visible
between. Postnuclear whorls with broad, rounded, prominent,
slightly protractively sinuated radial ribs, 78 on the body whorl,
whose interstices are 2-4 times their width. Microsculpture of
relatively prominent radial riblets crossed by barely visible, much
smaller spiral riblets with a secondary sculpture of a few narrow,
widely spaced spiral cords visible on part of body whorl and base of
shell. Sutures moderately deep, whorls strongly rounded above with
almost evenly rounded outer margins. Umbilicus barely perforate,
strongly constricted by growth of whorls and reflection of basal lip,
contained 20 times in the diameter. Aperture compressedly ovate
with slightly flattened basal margin, inclined less than 5° from shell
axis. Parietal barriers 4. extending slightly more than one-quarter
whorl: upper high, lamellate posteriorly with very gradual anterior
descension; 2nd and 3rd with lamellate portion extending less far
anteriorly; lower parietal greatly reduced in height with long,
threadlike anterior portion. Columellar wall with thick, heavy callus
surmounted by single, ridgelike, moderately recessed columellar
barrier that slants slightly downwards across midportion of callus.
Palatal barriers 4, extending slightly more than one-eighth whorl,
lower 3 high, ridgelike, more gradually descending anteriorly from
bottom to top: upper a much lower, threadlike ridge situated
opposite upper parietal. All major barriers slightly rounded and
minutely barbed above. Height of holotype 2.50 mm., diameter 3.45
mm.
Holotype. — Gambler Islands. Collected during the
voyage of the "Astrolabe." Musee Royal d'Histoire
Naturelle de Belgique, ex Dautzenberg, Geret, Ancey,
and Dupuy collections.
Range. -- Aukena, Mangareva, Agakauitai, Tar-
avai, Akamaru Islets, Mangareva, Gambier Islands.
Material. — Gambier Islands: Mangareva; Aukena
Islet (Stations 82, 88, 102, 103) on open ground (164
specimens, BPBM 9412, BPBM 9415, BPBM 9667,
BPBM 138683, BPBM 138699-700, BPBM 138703,
BPBM 138752-3, BPBM 138795); Agakauitai Islet
(Station 195) on sandy soil (8 specimens, BPBM 9670,
BPBM 138897-8); Taravai Islet (Stations 123, 126) on
cliffs (4 specimens, BPBM 9674, BPBM 138880);
Akamaru Islet (Station 107) on sandy soil (2 speci-
mens, BPBM 138851); Mangareva Islet, Ganhutu
(Station 142, 277) (44 specimens, BPBM 9639, BPBM
138938-40, BPBM 138966-7, BPBM 138969), Man-
gareva Islet (Station 197), Vaituatai Bay (6 specimens,
BPBM 139010-1); Mangareva Islet, vicinity (Station
155, 187, 189) of Rikitea (16 specimens, BPBM 9648,
BPBM 9678, BPBM 139000, BPBM 141664-5, BPBM
141689-90).
Remarks. — Ancey based the species Pitys hamy-
ana upon a single shell from the Gambier Islands
that was in a lot of Anceyodonta sexlamellata. The
original description of this previously unfigured species
indicated the presence of 4 parietal and 5 palatal
barriers, "four below the periphery" and "a smaller one
above." Ancey's type is a specimen with 4 parietal
barriers. It is obvious that he considered the colu-
mellar as one of his lower 4 palatals.
Although reported from all five major islets of
Mangareva, there are considerable differences in the
abundance of this species on the various islands (table
LXXI), and of the proportionate representation of
those with 3 and 4 parietal barriers (table LXXIII).
Specimens were most common on Aukena Islet
(table LXXIII) with three individuals of the 4-barrier
form (fig. 90d) for every one of the 3-barrier variety
(fig. 90a, e). Distribution was not random, since at
Station 82 only the 4-barrier form was found, while at
Station 88, there were nine of the 3-barrier variety for
every one of the 4-barrier. On Mangareva Islet only
four out of 66 specimens had 4 parietals, the remaining
62 having 3. During the original study of this material,
I had the impression that shells with 4 parietals
tended to be slightly higher and with a smaller
umbilical perforation than those with 3 parietals, but I
am uncertain whether this correlation is not based on
size variation later discovered in A. obesa rather than
barrier count. Possibly there is a stratigraphic differ-
ence between the forms, but present information does
not permit any conclusions.
In the Ganhutu area of Mangareva Islet (Stations
142, 227) and near Rikitea (Station 187) some
individuals had a heavier apertural callus and stronger
spiral sculpture with a slight tendency toward
flattening of the upper whorls (fig. 90e). No division of
the entire population from these areas into two forms
could be made and again I consider this to be an
extreme of individual variation. Similar variants were
seen in A. obesa.
SYSTEMATIC REVIEW
TABLE LXXIII. - BARRIER VARIATION IN ANCEYODONTA HAMYANA
207
Islet
Aukena
Agakauitai
Taravai
tt
Akamaru
Hangar eva ( Ganhutu )
tt !»
(Vaituatai )
" (Rikitea)
tt tt
tt tt
it it
Aukena
TOTALS
Station
Number
82
88
102
103
195
126
123
107
Number of
Parietal Barriers
Three
36
5
6
2
142
13
277
31
197
6
155
2
189
6
187
h
Four
98
U
15
3
2
2
2
111
2
1
1
1
131
Genus Cookeconcha, new genus
Endodontidae with typical apical sculpture in those species with
prominent palatal barriers (except ringens), absent on first half to
whole apical whorl in species with reduced or no palatals.
Postnuclear whorls with narrow-to-wide, generally prominent,
protractive radial ribs, reduced only in paucicostata. Microsculpture
typical, secondary cording only in decussatulus and lanaiensis
(faintly). Some species (hystrix) with long periostracal hairs. Apex
and spire flat or depressed (seven species), weakly elevated (seven
species), moderately elevated only in contortus and thwingi, H/D
ratio near 0.500 only in henshawi, contortus, subpacificus, thwingi,
and nudus. Body whorl evenly rounded in most species, laterally
compressed only in subpacificus and an undescribed species,
compressed above and below periphery in thaanumi, decussatulus,
and lanaiensis, greatly modified in stellulus. A weak supraperipheral
sulcus present in hystricellus, extensive sulci in stellulus, none in
other species. Whorls 4-5'/2, number closely correlated with size.
Umbilicus widely open, generally V-shaped, moderately decoiling,
margins rounded, last whorl sometimes decoiling more rapidly,
contained 2.50-3.50 times in the diameter (narrower only in
paucicostatus, nudus, and some hystricellus}. Size minute to very
large. Parietal barriers 2, varying from quite large with upper bifid to
having the lower lost with upper a threadlike ridge. Columellar
barrier normally present only in henshawi, cookei, and some
hystricellus. Palatal barriers 4 or 5 in smaller species (henshawi.
cookei, nudus, contortus, ringens), reduced in size and variable in
number in elisae, luctiferus, hystricellus, and stellulus, absent in
other species. Pallial region typically Endodontidae. Hermaphroditic
duct straight or convoluted, talon with globular head and short,
thick shaft. Penial retractor arising from diaphragm, inserting
directly on head of penis. Vas deferens entering penis subapically,
between pilaster U. Penis of varying length, without apical extension,
internally either with narrow, elongated pilasters (jugosus) as in
Endodonta or Nesophila, or shortened and enlarged (hystrix,
hystricellus) as in Australdonta. Jaw consisting of numerous, partly
to almost completely fused, narrow plates. Radula atypical in its
extremely elongated teeth and equal cusping of the marginals, which
have square, rather than rectangular plates.
Type species. — Helix hystrix Pfeiffer, 1846.
The diverse species grouped here show trends
quite different from those in the related genus
Endodonta. The latter species retain prominent aper-
tural barriers, have the umbilicus U-shaped and used
as a "brood chamber," show a strong tendency toward
loss of all sculpture, have developed a keeled pe-
riphery, and are strictly terrestrial, living under twigs
and dead leaves (Pilsbry and Vanatta, 1906, p. 783) or
in talus slopes (Cooke, 1928, p. 14). Cookeconcha
shows a marked tendency towards loss of the apertural
barriers, has the umbilicus V-shaped and regularly
CM
-t-
10
o
o
O
O
O
o
o
H
EH
o
X
3
H
PP
u
O5
CM
•2
TO
S
TO
IO
CM I
rH IO
0 CM
00
O
.IP
TO
O TO
TO
a
C-
CT
1
^f
5
00 «
«?
TO £^
CO
^»
IO
1
*x^
rH
•*
TO
-• —
ST
TO
lO
_o
o
4-t
S
CM
CM
IO
TH I
O t-
O TO
O IO
%
IO
Q
*X^
O
O 0
0
CO
TO
10
0
^-\
OO
4)
TO 1
|5
CO
IO rH
02
1)
OO
0 C-
CM
nj
rH
O TH
CM*
Q
O5
e-
TH
rH*
0
rH
TO 1
_op
tr-
CO CM
CO 05
S
"u
X
io
O O
•
-Hi
O
£
CM CM
ST
CM
CM
CM
£
CM
IT
CM
IO
0
CM
O
CO
rH
CM
S
CM
So
TO
•S
TO
CM'
TO
TO
TO
V
TO
^
i
S S J,
"°_ 0 CM
00
O
O
O
CM
CO
O
0
do
TO
CO 1
CO Tf
0 rH
TO
O>
0
1
IO
0
00
0
rH
1
TO
TO
O 1
CD -^i
O CO
Tf I
TO ^<
O C-
p
TO 0- „'
TO
o
CM'
o
TO
O TO
0*
TO
0
TO
o" CM'
O TO
a
C~
-rl
CO
* — *
CO
*~^
O>
-H
O>
*
-H
C»
^
CO
CO
CO
CO
CM
TO
-=f
c-
O
CT
CM'
TO
TO
co'
TO
CM'
•*'
§
IO
o
rH I
IO 00
TH OO
O5
02
O
10
CM'
o i
TH CM
rH rH
o CM'
o
TO
§
CO I
t— -^
o o
O iH
10
o
IT-
• 10
0 CO
CO
CO
I "3
00 '
TO
CM i
CM CM
O CM
O TO
TO
TO
S
• IO
C-
TO
OO
>ol
101
CO
•*
•^
CM
rH|
o
O
rH|
O
TH|
CM
0
CM
CM
IO
O
CD
TH
TO
CO 1
CO Tf
0 TH
CO
TO 1
O2 IO
0 0
00 1
0 TO
rH TO
O CO
0 TO
0 TO
a>
CM
O2
TO
a>
co'
co'
TO
?"
CM"
*^
5"
CM «
>f
10^
T— I
.« rH
>?
10"
1-1
i TO
S«
"i
10 ^-.
c-
10
*— '
IO
s
£•
IO
10
£-
*
£>
O3
-*
o
IO 1
TO IO
CM CO
o •*
o
IO '
O> t^
o o
0 -*
d
CO C^
O CM
0 •*
O O
CO
rH
1O
o o
-H ^
O>
CO
•*
0 0
o
to
•<f
O
o
o
TH
rH
to
sr
CM
CO i
O2 CM
0 C-
CO 1
CM rH
rH C7>
10'
CO I
TO rH
O TO
OO
OO
o co'
O TO
rH
IO
TO
•*"
•*'
o"
TO
oo"
OO
c-
CM'
CO 1
TO -tf
TH rr-
rH
cn i
TO OO
0 CO
CM'
TO i
CO rH
0 CO
O TH
0 rH
0 rH
TH
O
OO
t—
O
CM'
rH
CM*
•** co
rH 1
. t-
0 C-
00
o"
TH I
. rH
CM
0*
TO CO
TH I
> CM
CM •<#
O
0
CO
rH
rH
IO
O
rH I
O2 t—
O C-
O TO
O O
00
O
O
CM
IO
CO i
CO Tf
O CO
o ^*
CO
3
CM
O I
CO TH
O CO
O rH
TO
O
10
TO IO
cn i
• TO
p
*
O O
O3
*
co'
Ol I
•* CO
rH 00
O5
O
O CM
c-
CM*
Q
ta
U
B
a
10
TH
•*
TO
00*
CM'
0
Oi CO CO CD
O CD C3 c0
. . . TH . . co •*
CM IT- Ol CO . IO -^ OO <J2 OT
CM O2 TH O O IO C72 TH 00 OO
i/3 00 -^
•<Ji iH TO CO 0 CMrHtO CO to
CD CD 00 CD
CDTOO CO O5 COTOO rH iH
iO -^ lO -^
** c- 0i -^ TH ^ C- O"i ">
rH rH
C )
.-H
u— 3
Name
subpacifit
USNM
henshawi
X a. X
1 - z 'Ni
* th r
o »J
XXX %
z z z 2
3222 S
.g u, u, u. £
g 8
X !S X S
Z "a g Z g
t^ U ^ S* 73
<= y
•C r3
XXX S
III 8
fT< fw , f»t £3
x:
X X
Z Z
2 S
208
TO
<N
oo
CO
TO
TO
C-
(N C-
i-l O
OJ
TO
TO TO
r-l CO
CO
TO
TO
TO
CO I
rH IN
rH O
O TO
-H — '
OJ
rH
TO
&
10
IN
OJ <
<M OJ
O TO
IN
TO
€
rH
IO
CO
CO
•X.
IO
•*
<N
CO
IO
TO1 5
• •
o o
10
IO
TO
P
C-
U5
O ^"
o o
CO
10
s
TO
rH
o
CO
CM
TO
•*
•*
10
0
o
o
o
0
c-
CO
rH
TO
TO
^t
00 •*
CO
o
rH
CD
0
CO
O IO
o
O
TO
o
CO
0 TO
o
TO
O
•4"
0
O
o
0
0 0
o
O
O
0
HH
-H
-H
-H
OJ
00
s
£
B-
CO
TO
TO
TO
•*t
•*
0
O
O
o
o
•
s
*
to
s
i/3
10
TO
V
O i
CO I
OJ '
O i
CO
o
33
CO rH
rH CO
rH OJ
O •*
•* IN
rH OO
TO
o V
O -^i
O TO
O TO
CO
rH
(N "~
O
OJ
O
IO
O
o
rH
10
IN
C-
•*
oa
CO
TO i
tN co
<N (N
o' 10
o
(N
TO
C- CO
O OO
TO
O
00
10
a?
x^
O
So
00
x-^
C-
*—,
0
0?
00
c-
TO
IO
OJ
c-
IN
IN
CN
rH
rH
rH
IN
TO
OO i
rH '
OJ 1
OJ 1
O i
OJ c
IO C—
rH IO
IN CO
VO IO
CO O
OJ TO
rH OJ
o o
O TO
0 Tf
O IO
0 TO
O CO
O rH
O <N
O rH
0 rH
0 rH
0 (N
O (N
IO
-H * —
00
e-
TO
t-
IO
TO ^
TO
TO
TO
IO
C-
^
00
c—
o
fr-
•*
«
O
C- IO
CO C-
•* eo
00 C-
TO C-
O CO
CO 1
00 >
TO i
O i
co >
TO 1
. CO
• T— 1
• O
• c~
. o
. CO
1
iH -^"
TO TO
IN CO
IN CO
(N IO
TO 1O
-H ' —
c-
TO ""
B-
O
-H *— '
TO
-H —
CO
1
(— 1
iH
•*
rH
•*
(N
1
IO
•*
CO
c-
CO
CO
1
o
CO
rH CO
(N C-
1O TO
OJ
IO
c-
TO O
o
TO
TO
OJ OJ
IO
^-.
IN
rH OO
IO
3
CO
CO
TO rH
rt
^
^
C- OJ
X
Z
8
X
Z
1
z
X X
2 xz
2
u
o
C
2
£ a
2
u.
</>
a
•s
£
IO CO
O TO
CO CO
1
CO O
Tjl OJ
3
X X
3 z
o
u- u-
&
-3
c-
TO
U
rt
a
CO CO
rH rH
<N' CM"
o o
o o
OJ OJ
X X
2 2
2 ?,
m 03
OJ
OJ
CO
CO
qlu,
1
X
2
209
210
SOLEM: ENDODONTOID LAND SNAILS
decoiling without developing a U-shaped brood cham-
ber, retains major radial ribbing, but shows a tendency
towards loss of apical sculpture, never has a keeled
periphery, and will live under bark on dead stumps
and logs (Pilsbry and Vanatta, 1906, p. 783), in heavy
moss on stones and trees (pers. observation), as well as
in the dead leaf habitat. Nesophila probably is derived
from a form very similar to Cookeconcha jugosus, and
is specialized in the splitting of the parietals into
threadlike traces plus shouldering of the umbilical
margin.
Cookeconcha and Endodonta share the bifid
upper parietal, otherwise seen only in the Raivavae
Island Minidonta gravacosta and M. micraconica,
plus the Mangarevan Anceyodonta alternata and A.
andersoni. In these species the bifidity is distinctly on
the lower side of the main blade (fig. 65d, e), while in
the Hawaiian taxa it is much closer to the expanded
upper edge and shows a distinct tendency to fuse with
the main blade in the larger species of Cookeconcha
and Endodonta.
Cookeconcha is unique among the Pacific Island
Endodontidae in its tendency toward loss of the early
apical sculpture while retaining the postnuclear sculp-
ture. Its tendency toward reduction of the apertural
barriers is more persistant and extends further than in
Libera and thus parallels Nesodiscus.
Anatomically, the species show differences that in
other areas are taken, together with conchological
data, to indicate generic level separation. The four
populations from Oahu, hystricellus, hystrix, and two
unnamed species, one (BPBM 23902) most similar to
hystrix and the other (BPBM 35835) most similar to
hystricellus, have the penis altered internally much as
Australdonta raivavaeana (fig. 125b). The pilasters
are shortened, greatly broadened and enlarged, then
tapering anteriorly. The totally different talon struc-
ture, lack of a fleshy head to the penis, and greatly
different pattern of shell structure in Australdonta
and Cookeconcha show that the similarity of pilaster
pattern in the penis is convergent. C. jugosus has the
elongated pilaster pattern found in Endodonta and
Nesophila and agrees with them in all anatomical
features except coiling of the hermaphroditic duct.
None of the small Cookeconcha have been dissected.
Quite probably jugosus and the hystrix -hystricellus
group eventually will be placed in separate genera.
The fusion of jaw plates is a correlative of large size,
but the great elongation of the radular teeth and
equal-sized cusps of the marginal teeth are quite
different from the normal Endodontidae. Unfortunate-
ly, I could not dissect any of the henshawi complex.
The present review of trends is based on such
limited material that I refuse to try to subdivide this
group. The collection at the Bernice P. Bishop
Museum contains about 2,600 sets with at least 25,000
specimens, probably representing about 160 species-
level units. Despite the wide differences in size and
apertural barriers (table LXXIV), even the limited
material used in this study shows a clearly monophy-
letic assemblage. Only when the abundant Bishop
Museum material is reviewed can the possibility of
generic or subgeneric separation be considered. Until
then, Cookeconcha should be viewed as more broadly
defined than the other genera used in this study.
Four levels of specialization can be recognized.
First, the minute-to-small species (mean diameter 1.79-
3.35 mm.) in which the palatal barriers are fully
developed, the upper parietal clearly bifid, sculpture is
retained on the entire apex, and the last whorl of the
umbilicus may decoil slightly more rapidly. The
described species are:
Cookeconcha henshawi (Ancey, 1904)
C. cookei (Cockerell, 1933)
C. thwingi (Ancey, 1904)
C. nudus (Ancey, 1899)
C. subpacificus (Ladd, 1958).
Inclusion of the latter is based upon a preponderance
of similarities in remaining portions of the single
partial specimen, despite total absence of most
apertural barriers (p. 212).
Second, there are distinctly larger, but still
relatively small (mean diameter 3.88-4.14 mm.) species,
which retain a full apertural barrier complement
(although lacking a bifid upper parietal), either typical
apical sculpture (contortus) or with apical sculpture
absent on first whorl (ringens), and the umbilicus is V-
shaped. The two described species are:
Cookeconcha contortus (Ferussac, 1824)
C. ringens (Sykes, 1896)
Both species have the barriers simpler and proportion-
ately smaller than do members of the C. henshawi
complex.
Third, there are the species in which partial-to-
great reduction of the palatal barriers has taken place,
the parietals are reduced in height, apical sculpture is
reduced to lost, the size is fairly large (mean diameter
4.28-6.09 mm.), and the umbilicus regularly V-shaped.
Included here are:
Cookeconcha luctiferus (Pilsbry & Vanatta, 1906)
C. elisae (Ancey, 1889)
C. hystricellus (Pfeiffer, 1859)
C. stellulus (Gould, 1844).
C. hystricellus is specialized in developing a suprape-
ripheral sulcus, while C. stellulus has the shell
appearance drastically altered through the presence of
two deep sulci, enlargement of the ribs, increase in rib
spacing, and recession of the palatal lamellar traces.
Fourth, there are the species in which all palatal
and columellar barriers have been lost, the size
increased (mean diameter 3.06-6.18 mm.), most of the
apical sculpture lost, and sometimes secondary spiral
sculpture (decussatulus, lanaiensis) developed, or the
primary sculpture reduced (paucicostatus). The de-
scribed species are:
SYSTEMATIC REVIEW
211
E
ste! lulus
paucicostatus
I
I
hystficellus
I
I
I
I
I
I
3
5
6
9
10
11
7 8
mean ribs/mm
FIG. 91. Relationship between mean diameter and mean ribs per mm. in Cookeconcha
12
13
Cookeconcha hystrix (Pfeiffer, 1846)
C. paucicostatus (Pease, 1870)
C. paucilamellatus (Ancey, 1904)
C. thaanumi (Pilsbry & Vanatta, 1906)
C. decussatulus (Pease, 1866)
C. lanaiensis (Sykes, 1896)
C. jugosus (Mighels, 1845).
The simplicity of apertural barrier configuration has
led to recording of species in the above series from
several islands. Probably most of these can be shown
to be in error when the specimens are restudied.
Even casual inspection of the species show that, in
general, size increase is accompanied first by sim-
plification of the apertural barriers, then, successively,
partial loss of the palatals, complete loss of the
palatals with partial reduction and/or loss of the lower
parietal. Plotting of the relationship between mean
diameter and mean ribs/mm, (fig. 91) shows a
characteristic simple, direct relationship, except for C.
paucicostatus (rib reduction), C. stellulus (rib enlarge-
ment), and C. jugosus (gerontic rib crowding near end
of body whorl).
Nothing significant can be said about distribution,
since patterns suggested by the above groupings are
caused by limited sampling. The C. henshawi complex
is known mainly from Hawaii (by accident of study),
but I have collected undescribed species from both
Oahu (Waianae Mountains) and Kauai. Similarly, a
new species of the C. contortus group from the
Waianae Mountains has the secondary sculpture of C.
decussatulus and the body whorl is laterally
compressed. I fully expect that almost every conceiv-
able combination of characters that are seen individ-
ually in Cookeconcha reviewed here, will be found in
the unstudied Hawaiian material.
Cookeconcha subpacificus (Ladd, 1958). Figure
92.
Ptychodon subpacificus Ladd, 1958, Journ. Paleontol., 32, (1) pp.
189-190, pi. 30, figs. 7-8-Drill hole 2B at 1,807-1,818 ft. depth,
Bikini Atoll, Marshall Islands (Miocene e).
Description. — Shell very small, probably with 4 normally coiled
whorls when complete (only 3>/2 remaining). Apex and spire barely
emergent, almost flat, last whorl descending much more rapidly,
H/D ratio of remaining shell 0.522. Apical whorls 1%, sculpture of
prominent retractive radial ribs and faint indications of micro-
sculpture near end of apex. Lower whorls with strong, retractively
sinuated radial ribs, 77 on last remaining whorl, whose interstices are
1-2 times their width. Microsculpture clearly visible and consisting of
very fine radial riblets and slightly finer, more crowded spiral riblets.
Whorls strongly rounded above and on umbilical shoulder,
compressed laterally with evenly rounded lower palatal and basal
margins. Only very faint traces of irregular radial color markings left
on shell above periphery, not detectable on base. Umbilicus widely
open, V-shaped, rather rapidly decoiling, contained 3.53 times in
diameter of remaining shell. Last one-half whorl missing, hence
status of columellar and palatal barriers unknown. Aperture
212
SOLEM: ENDODONTOID LAND SNAILS
flattened laterally, probably inclined about 15° from shell axis.
Parietal wall with partial remains of two barriers, both extending
posteriorly one-quarter whorl and broken off in mid-section. Lower
parietal broader, slightly lower, with longer, more gradual anterior
descension than upper, but still descending rather rapidly. Both
parietals with very gradual posterior descension. Height of holotype
0.97 mm., diameter 1.86 mm.
Flo. 92. Cookeconcha subpacificus (Ladd). Detail of parietal
lamellae remnants. Greatly enlarged. (MM).
Holotype. — Marshall Islands: Bikini Atoll, drill
hole 2B at 1,807-1,818 ft. depth (Miocene e). USNM
562090.
Range. — Fossil at Bikini Atoll, Marshall Islands.
Material. — Only the holotype is known.
Remarks. — Despite being only a fragmentary
specimen, I have no hesitation in classifying this
species with the henshawi group of Cookeconcha.
There are a number of shell characters that agree with
members of the henshawi complex and contrast with
the character states seen in Minidonta, the other
logical possibility. These are the only two genera in
the Endodontidae which have species reaching the size
range of subpacificus. Although Minidonta has seven
species with a mean diameter 2.00 mm. or less, while
only Cookeconcha henshawi is known to be that size,
it cannot be overemphasized that the Hawaiian
Cookeconcha probably number eight or ten times the
species discussed here. Particularly when allowance is
made for the missing half whorl of subpacificus, an
actual diameter of slightly over 2 mm. is probable.
Whorl count in the 1.68-1.83 Minidonta is 4i/i6 to
4'/z; 3'/2 in subpacificus and C. henshawi. The
umbilicus is U-shaped and rather narrow (mean D/U
ratios 3.67-7.10) with the last whorl decoiling more
rapidly in the small Minidonta; V-shaped, regularly or
with a slightly more rapidly decoiling last whorl and
wider [mean D/U ratios 2.66-3.68 in Cookeconcha; V-
shaped, widely open, and rather rapidly decoiling (D/U
3.53) in subpacificus]. The missing half whorl increases
the D/U ratio and also raises the H/D ratio. Probably
the true D/U ratio of subpacificus would be about 3.2-
3.3, well within the range of Cookeconcha, but below
the range of Minidonta. In the latter genus, the spire
is moderately to strongly elevated in all small species
except M. gravacosta, with mean H/D ratios of 0.573-
0.625; in the small Cookeconcha, the spire is barely
emergent and the mean H/D ratio 0.497-0.538. Consid-
ering that the missing half whorl of subpacificus
means a slightly (8-10 per cent) higher H/D ratio, its
barely emergent spire and H/D ratio of 0.522 follow
the Cookeconcha pattern. The small Cookeconcha and
subpacificus have the aperture inclined 10-15° from
the shell axis, while in Minidonta it is usually inclined
5°, only in M. micro and M. hendersoni reaching 10°.
Thus the 15° inclination of subpacificus agrees with
Cookeconcha. Lateral compression of the body whorl
is common in Minidonta, but rarely seen in Cooke-
concha. In this respect, subpacificus resembles Mini-
donta, but the shift from evenly rounded to laterally
compressed, or visa versa, is a common change.
Minidonta normally has 3 parietals: when reduced to
2 in number, the lower parietal is very gradually
descending. The 2nd parietal in Minidonta always
extends significantly beyond the anterior end of the
upper parietal. In Cookeconcha there are only 2
parietals, the 2nd of which only extends slightly
beyond the upper and is either threadlike or sharply
descending anteriorly. The 2 parietals of subpacificus,
with the 2nd sharply descending and extending only
slightly beyond the upper clearly indicate relationship
to Cookeconcha rather than Minidonta. Rib frequency
in subpacificus (13.18 ribs/mm.) is more similar to
Minidonta (ribs/mm. 10.7-25.2) than to the small
Cookeconcha (ribs/mm. 7.79-13.5), but is within the
range of observed variation. Finally, the appearance
and spacing of the microsculpture in subpacificus
more closely resemble that of Cookeconcha than
Minidonta.
Only in lateral compression of the body whorl and
rib spacing does subpacificus more closely resemble
Minidonta. The great majority of features — whorl
count, umbilical shape, umbilical width, spire eleva-
tion, H/D ratio, apertural inclination, number of
parietal barriers, position of the 2nd parietal, and
microsculpture — subpacificus agrees with Cooke-
concha.
Unfortunately, the tops of the parietal barriers in
subpacificus are broken off and the entire columellar
and palatal whorls are missing for one-half whorl.
Only the extremely unlikely prospect of new coring
work on Bikini and collection of additional specimens
will allow a more detailed analysis of subpacificus.
Study of the complete parietal and palatal barriers
would be needed to be certain whether subpacificus
belongs to the Cookeconcha henshawi complex; is a
Cookeconcha belonging to a group more generalized
than any now living in Hawaii; or is generically
separable from Cookeconcha. I consider that either of
the first two statements has a much greater probabil-
ity of being correct than the third. In the absence of
data differentiating subpacificus from the henshawi
group, I prefer to consider it only specifically sepa-
rable.
SYSTEMATIC REVIEW
213
Cookeconcha henshawi (Ancey, 1904)
Endodonta (Thaumatodon) henshawi Ancey, 1904, Jour. Malacol.,
11, p. 67, pi. 5, figs. 15, 16 - Palihoukapapa, Hamukua slope of
Mauna Kea, Hawaii, Hawaiian Islands.
Diagnosis. — Shell minute; diameter 1.71-1.89 mm. (mean 1.79
mm.), with S'/i-S'H rather tightly coiled whorls. Apex and spire
slightly and evenly elevated, last whorl descending slightly more
rapidly, H/D ratio 0.537-0.539 (mean 0.538). Umbilicus open, U-
shaped, last whorl decoiling more rapidly, contained 3.25-3.29 times
(mean 3.27) in the diameter. Apical sculpture of larger radials with
very fine microradials and microspirals. Postnuclear sculpture of
high, prominent, protractive radial ribs, 46-51 (mean 48.3) on the
body whorl, whose interstices are 3-5 times their width. Micro-
sculpture of very fine radial riblets, five to eight between each pair of
major ribs, crossed by extremely fine and crowded spiral riblets.
Sutures impressed, whorls strongly rounded above and on basal
margin, evenly rounded on outer margin. Aperture subcircular, with
evenly rounded outer margins, inclined about 10° from shell axis.
Parietal barriers 2, extending posteriorly less than three-sixteenths of
a whorl: upper very high on posterior half, indistinctly bifid, with
gradual anterior descension from front edge of expanded portion; 2nd
slightly lower, broadly expanded above on posterior half, with sharp,
then gradual, anterior descension to point in front of upper parietal
termination. Columellar barrier high and bladelike, broadly ex-
panded posteriorly, lying parallel to plane of coiling, with moderate
to sharp anterior descension almost to lip edge. Palatal barriers 4,
extending posteriorly less than one-eighth whorl, slightly recessed
within aperture, with one prominent accessory trace between 3rd and
4th palatals: lower greatly reduced in height, a raised crescentic
ridge, broadly expanded above; 2nd twice as high as 1st, flattened
and broadly expanded above on posterior half, with gradual anterior
descension, upper edge lying close to top of 2nd parietal; 3rd slightly
reduced in height, pointing between parietals, with equal posterior
expansion and more gradual anterior descension; 4th supraperipher-
al, equal in height to 1st palatal, but much less expanded above,
moderately recessed within aperture.
Range. — Hamakua slope of Mauna Kea, Hawaii,
Hawaiian Islands.
Material. — Hawaiian Islands: Hawaii, "Mana" (5
specimens, FMNH 46563, ex Webb, Gude, Hartley).
Remarks. — The indistinctly bifid upper parietal is
a character shared with C. nudus, C. thwingi, and C.
cookei. The much smaller size, heavier ribbing, lower
whorl count, and more elevated spire separate C.
henshawi from the other species.
Ancey 's types were larger (diameter 2 mm. with 4
to 4'/4 whorls) than the specimens seen during this
study. The latter are subadult and future use of the
diagnosis presented above should allow for this fact in
comparing size and shape factors.
Cookeconcha cookei (Cockerell, 1933)
Endodonta (Thaumatodon) cookei Cockerell, 1933, Nautilus, 47,
CD, p. 58 — dead tree fern on Mt. Tantalus, Koolau Mountains.
Oahu, Hawaiian Islands.
Description. — Shell very small, with 4% normally coiled whorls.
Apex and spire almost evenly elevated, slightly rounded above, body
whorl descending moderately more rapidly, H/D ratio 0.538.
Embryonic whorls 1 Hi, sculpture eroded except for faint traces of
radial ribbing in unclogged portion of sutures, visible in umbilicus as
major radials with one or two microradials between, plus weak
microspirals, present to top of apex. Postnuclear sculpture worn off
spire, on lower whorls consisting of very high, prominent, strongly
protractively sinuated radial ribs, 60 on the body whorl, whose
interstices are 2-3 times their width. Microsculpture of extremely fine
radial riblets, six to ten between each pair of major ribs, crossed by
slightly finer and more crowded spiral riblets. No secondary
microsculpture. Sutures deep, whorls strongly rounded above and on
basal margin, with evenly rounded, slightly laterally compressed
outer margin. Color mostly leached from shell, traces of widely
spaced, narrow to broad, reddish flammulations visible above
periphery, fading out on body whorl. Umbilicus broadly U-shaped,
regularly decoiling until last third of body whorl, which decoils a
little more rapidly, contained 3.08 times in the diameter. Aperture
ovate, strongly rounded above and on basal margin, slightly
compressed laterally, inclined about 15° from shell axis. Parietal
barriers 2, extending posteriorly three-sixteenths of a whorl: upper a
high lamellar blade, bulbously expanded and serrated above on
posterior third, bulbous section descending to three-eighths point,
then the blade continuing anteriorly without descension until just
before termination, when it descends sharply; 2nd slightly less
elevated than 1st, more broadly and bulbously expanded above over
posterior five-eighths, swollen section then tapering to about one-
eighth from end, then descends more gradually than upper to point
anterior to upper termination. Columellar barrier high and crescen-
tic, thick, but only slightly expanded above, slanted downwards from
plane of coiling at 45° angle, with abrupt descension to top of
Columellar callus. Palatal barriers 4, extending posteriorly about one-
eighth whorl, deeply recessed: lower basal in position, short,
crescentic, slightly higher than wide, much lower than columellar;
2nd and 3rd equal in height to columellar, crescentic, broadly
expanded and serrated above, subperipheral, with progressively more
gradual anterior descension; 4th supraperipheral, more deeply-
recessed, slightly higher than 1st, much lower than 3rd, crescentic,
with abrupt anterior descension. Height of holotype 1.24 mm.,
diameter 2.29 mm.
Holotype. — Hawaiian Islands: Oahu, slopes of Mt.
Tantalus, Koolau Mountains. Collected in a dead tree
fern by T. D. A. Cockerell on July 16, 1924. ANSP
158823.
Range. — Mt. Tantalus, Koolau Mts., Oahu,
Hawaiian Islands.
Material. — Only the holotype was seen.
Remarks. — The wider umbilicus, more prominent
and crowded ribbing, deeper recession, and larger size
of the apertural barriers separate C. cookei from C.
henshawi. In the latter the parietal and palatal
barriers are much less expanded above and have a
distinct gap, while in C. cookei the upper parietal and
3rd palatal almost overlap. C. thwingi is more
depressed, has a wider umbilicus (table LXXIV), lacks
a columellar barrier, and has two accessory palatal
traces. The great expansion of the apertural barriers in
C. cookei is not equalled by any other described
member of the genus, but is equivalent to the situation
seen in some Minidonta, Anceyodonta, and Thaumato-
don.
Cookeconcha thwingi (Ancey, 1904)
Endodonta thwingi Ancey, 1904, Jour. Malacol., 11, (3), p. 66 —
extinct crater on Kona coast, Hawaii, Hawaiian Islands.
Diagnosis. — Shell very small, diameter 2.12-2.50 mm. (mean
2.30 mm.), with 4-4'/2 rather tightly coiled whorls. Apex and spire
moderately and evenly elevated, last whorl descending distinctly
more rapidly, H/D ratio 0.488-0.520 (mean 0.499). Umbilicus widely
open, V-shaped, regularly decoiling, contained 2.62-2.74 times (mean
2.66) in the diameter. Post nuclear whorls with high, prominent,
protractively sinuated radial ribs, 65-70 (mean 66.7) on the body
whorl, whose interstices are 2-4 times their width. Microsculpture of
214
SOLEM: ENDODONTOID LAND SNAILS
fine radial riblets, five to eight between each pair of major ribs,
crossed by extremely fine and crowded spiral riblets. Sutures
impressed, whorls strongly rounded above, with evenly rounded outer
margins. Aperture circular, inclined about 15° from shell axis.
Parietal barriers 2, extending posteriorly less than three-sixteenths of
a whorl: upper rather high, bluntly bifid on posterior expanded
quarter, with gradual anterior descension; 2nd reduced in height,
moderately expanded posteriorly, with sharper descension to an
elevated ridgelike portion that descends gradually. Columellar wall
without barriers. Palatal barriers 5, extending posteriorly about one-
eighth whorl, reaching lip edge, with two accessory traces located one
between 1st and 2nd, one between 2nd and 3rd palatals: lower at
baso-columellar margin, very high, moderately strongly expanded
posteriorly, with rather sharp anterior descension; 2nd and 3rd equal
in height and expansion, with progressively more gradual anterior
descension; 4th and 5th greatly reduced in height and length, broadly
expanded above, more deeply recessed within aperture, scarcely
larger than traces but recognizable as majors by being less deeply
recessed than the traces.
Range. — Extinct crater on Kona coast of Hawaii,
Hawaiian Islands.
Material. — Hawaiian Islands: Hawaii (4 speci-
mens, FMNH 46466 ex Webb, Gude).
Remarks. — Ancey did not publish a formal
description of this species, but in comparative remarks
about C. henshawi stated: "A similar species, also
probably extinct, but with a larger umbilicus, was
detected by the Rev. E. W. Thwing, in an extinct
crater of the Kona coast; it is undoubtedly another
new species which I propose to name E. thwingi, after
its discoverer." In 1904, such comparative remarks
were considered perfectly adequate for species differ-
entiation. While under current rules it could be argued
(probably successfully) that the lack of a formal
description invalidates this name, I choose to consider
that the citation of a formal name and comparative
remarks are sufficient to allow acceptance of this name
from Ancey 's paper.
The larger size (table LXXIV), wider umbilicus,
absence of a columellar barrier, 5 palatals with two
accessory traces and greater number of major ribs
separated Cookeconcha thwingi from the otherwise
very similar C. henshawi. The much larger C. nudus
lacks accessory traces, has a narrower umbilicus, and
sometimes has a columellar barrier.
Cookeconcha nudus (Ancey, 1899)
Endodonta (Thaumatodon) nuda Ancey, 1899, Proc. Malacol. Soc.
London, 3, (5), p. 268, pi. 12, fig. 1 - Olaa, Central Hawaii;
Sykes, 1900, Fauna Hawaiiensis, Moll., 2, (4), p. 288; Ancey,
1904, Jour. Malacol., 11, p. 66-Palihoukapapa, Hamakua slope
of Mauna Kea, Hawaii. Hawaiian Islands.
Diagnosis. - Shell small, diameter 3.22-3.49 mm. (mean 3.35
mm.), with 4 ''2 - 5 normally coiled whorls. Apex and spire slightly
and evenly elevated, last whorl descending a little more rapidly, H/D
ratio 0.449-0.524 (mean 0.497). Umbilicus open, V-shaped, last whorl
often decoiling more rapidly, contained 3.38-3.92 times (mean 3.68) in
the diameter. Apical sculpture typical. Postnuclear whorls with
narrow, prominent, protractively sinuated radial ribs, 75-92 (mean
83.3) on the body whorl, whose interstices are 2-4 times their width.
Microsculpture of fine radial riblets, three to five between each pair
of ribs, crossed by extremely fine and crowded spiral riblets. Sutures
impressed, whorls strongly rounded above and on basal margin, with
evenly rounded outer margin. Aperture subcircular, with evenly
rounded outer margin, inclined about 15° from shell axis. Parietal
barriers 2, extending posteriorly one-quarter whorl: upper very high,
weakly to prominently bifid on posterior five-eighths, with gradual
anterior descension; 2nd much lower, strongly expanded on posterior
half, with rather sharp descension to threadlike or raised lamellar
anterior third that terminates beyond edge of upper parietal.
Columellar barrier usually absent, sometimes (12.1 per cent) present
as a low, moderately recessed lamellar ridge lying parallel to plane
of coiling. Palatal barriers 5, extending posteriorly more than one-
eighth whorl: lower at baso-columellar margin, lower than 2nd,
strongly expanded above posteriorly, with sharp descension to lip
edge; 2nd and 3rd higher, less expanded above, with progressively
more gradual anterior descension; 4th very slightly reduced in height,
with more gradual anterior descension; 5th supraperipheral, more
flattened above on posterior expanded portion, reduced in height,
moderately recessed, with sharper anterior descension.
Description. — Shell rather small, with slightly less than 4'/2
normally coiled whorls. Apex flat, lower whorls descending slightly,
last whorl more rapidly, H/D ratio 0.465. Apical whorls 1%, sculpture
of fine radial riblets, with two or three microradials and barely
visible spirals. Postnuclear whorls with narrow, high, protractively
sinuated radial ribs, 67 on the body whorl, whose interstices are 2-4
times their width. Microsculpture of fine radial riblets, three to six
between each pair of major ribs, with barely visible, very crowded
spiral riblets. Sutures impressed, whorls strongly rounded above and
on basal margin, with evenly rounded outer margin. Color light
yellow-white, with narrow, irregularly spaced, reddish flammulations
that are strongly zigzagged just above periphery and fade out on
shell base. Umbilicus V-shaped, last whorl decoiling more rapidly,
contained 3.59 times in the diameter. Aperture subcircular, with
evenly rounded outer margin, inclined about 15° from shell axis.
Parietal barriers 2, structure as in diagnosis except bifidity of upper
well developed. Columellar barrier a small deeply recessed, threadlike
ridge, parallel to plane of coiling. Palatal barriers 5, shape as in
diagnosis: 1st slightly lower than 2nd; 3rd a little larger than 2nd;
4th slightly lower than 1st; 5th further reduced in height. Height of
holotype 1.18 mm., diameter 3.19 mm.
Holotype. — Olaa, Central Hawaii, Hawaiian
Islands. FMNH 46358 ex Webb, Gude, Ancey collec-
tions.
Range. — Hawaii, Hawaiian Islands.
Material. — Hawaiian Islands: Hawaii, Olaa (1
specimen, FMNH 46358); Kaiwiki, drift of Hilo, at
2,500 ft. elevation (15 specimens, FMNH 46422,
FMNH 73197, FMNH 90319).
Remarks. — The most obvious difference of C.
nudus lies in the presence of 5 major palatals and its
size, which is much larger than the other species with
bifid upper parietal — thwingi, cookei, and henshawi.
The other species with well-developed palatals, con-
tortus and ringens, lack any trace of bifidity in the
upper parietal barrier.
Cookeconcha contortus (Ferussac, 1824)
Helix contorta Ferussac, 1824, Voy. "Uranie"...Freycinet, Zool., p.
469 - Sandwich Islands; Ferussac, 1832, Histoire nat. moll. terr.
fluv., pi. 51a, fig. 2 - Sandwich Islands; Pfeiffer, 1848, Mon.
helic. viv., 1, pp. 185-186; Deshayes, 1851, Hist. nat. moll. terr.
fluv., 1, pp. 10-11; Pfeiffer, 1852, Syst. Conchyl. Cab., (1), 12, (2),
p. 197, pi. 100, figs. 1-5 (plate issued in 1850); Pfeiffer, 1853, Mon.
helic. viv., 3, p. 144; Reeve, 1854, Conchol. Icon., Helix, pi. 133,
fig. 647; Pfeiffer, 1859, Monog. helic. viv., 4, p. 155; Pfeiffer, 1868,
SYSTEMATIC REVIEW
215
Monog. helic. viv., 5, p. 220; Pease, 1871, Jour, de Conchyl., 19,
p. 96 - Oahu; Pfeiffer, 1876, Monog. helic. viv., 7, p. 256; Tryon,
1887, Man. Conchol., (2), 3, p. 63, pi. 12, figs. 8-10.
Helix intercarinata Mighels, 1845, Proc. Boston Soc. Nat. Hist., 2,
pp. 18-19 - Oahu.
Endodonta contorta (Ferussac), Albers, 1850, Die Heliceen, p. 89;
von Martens, 1860, Die Heliceen, ed. 2, p. 90; Pilsbry, 1893, Man.
Conchol., (2), 9, p. 26.
Pitys contorta (Ferussac), H. & A. Adams, 1858, Genera Recent
Moll., 2, p. 113; Pease, 1871, Proc. Zool. Soc. London, 1871, p.
474; Ancey, 1889, Bull. Soc. Malacol. France, 6, pp. 181-182.
Patula (Endodonta) contorta (Ferussac), Clessin, 1881, Nomen.
helic. viv., p. 96.
Helix (Pitys) contorta (Ferussac), Baldwin, 1893, Catalogue Land
and Fresh Water Shells, p. 16 - Oahu.
Endodonta (Thaumatodon) contorta Sykes, 1900, Fauna Ha-
waiiensis, Moll., 2, (4), p. 288-Oahu.
Diagnosis. — Shell slightly smaller than average, diameter 3.72-
4.14 mm. (mean 3.88 mm.), with 5'/2-534 rather tightly coiled whorls.
Apex and spire slightly and usually evenly elevated, body whorl
descending more rapidly, H/D ratio 0.465-0.556 (mean 0.516).
Umbilicus broadly V-shaped, regularly decoiling, contained 3.14-3.50
times (mean 3.29) in the diameter. Apical sculpture typical.
Postnuclear sculpture of narrow, prominent, strongly protractively
sinuated radial ribs, 77-87 (mean 80.8) on the body whorl, whose
interstices are 2-3 times their width. Microsculpture of fine radial
riblets, four to six between each pair of major ribs, crossed by
extremely fine and crowded spiral riblets. Sutures impressed, whorls
with evenly rounded outer margin, strongly rounded basal margin.
Aperture circular, inclined about 25° from shell axis. Parietal barriers
2, extending posteriorly slightly more than three-sixteenths of a
whorl: upper high and thin, weakly expanded above on posterior
third, with very gradual anterior descension; 2nd distinctly lower,
more broadly expanded on posterior elevated portion, anterior half a
raised threadlike ridge extending beyond end of upper parietal.
Columellar wall without barriers. Palatal barriers 4 or 5, usually 4,
extending posteriorly slightly more than one-eighth whorl: lower at
baso-columellar margin, lower than 2nd, slightly recessed, crescentic,
moderately expanded above, with rather sharp anterior descension;
2nd and 3rd higher, thinner, with more gradual descension both
anteriorly and posteriorly; 4th supraperipheral, half the height of
3rd, weakly expanded, more deeply recessed; 5th, when present,
located between 2nd and 3rd, equal in height.
Range. — Probably Waianae Mountains, Oahu,
Hawaiian Islands.
Material. — Hawaiian Islands: Oahu (4 specimens,
FMNH 46603, ex Webb, Gude, Geret, Ancey; Cardiff
ex Tomlin collection).
Remarks. — I suspect that several Waianae species
of the contortus-hystricellus syndrome have been
confused under this name. Ferussac (loc. cit.) figured a
flat (or depressed) shell with no visible major radial
sculpture, prominent setae, parietal barriers of equal
length and palatal barriers equally spaced. Pfeiffer, in
the Conchylien Cabinet, showed a shell with distinctly
elevated spire, narrower umbilicus, rather crowded
radial sculpture and mentioned that there are 3 - 5
palatal barriers. Reeve (loc. cit.) has a typically vague
figure that cannot be used for identification purposes,
but probably is based on a specimen from the same set
used by Pfeiffer.
The single specimen in Field Museum agrees well
with Pfeiffer's illustration and originated from the
Ancey collection, coming to Chicago through the
collections of Geret, Gude, and Webb. It is unusual in
having a 5th palatal barrier located midway between
the normal 2nd and 3rd. The National Museum of
Wales' examples are very similar.
In the available specimens, positioning of the
barriers is the same as in the smaller nudus, thwingi,
and henshawi, but, of course, there is no trace of
bifidity in the upper parietal, the palatals are much
less expanded and crescentic, rather than being
flattened above. The increase in size is accompanied by
a major increase in whorl count. In all specimens the
microradial ribbing is rather large, with four to six
between each pair of major ribs. The major ribs
themselves are rather crowded (mean ribs/mm. 6.64).
The type of Helix intercarinata Mighels, 1845 is
no longer extant (see Johnson, 1949, p. 226). Following
the historical precedent of considering this a synonym
of Helix contorta rather than trying to interpret
Mighel's abbreviated description will save time and
avoid confusion. When an analysis of the Waianae
Cookeconcha is accomplished, then selection of a
lectotype for Helix contorta from one of the several
British Museum, Brussels, or Bishop Museum sets
would be justified. At present it would be a waste of
time and paper.
Cookeconcha ringens Sykes, 1896
Endodonta ringens Sykes, 1896, Proc. Malacol. Soc., London, 2,
(3), pp. 126-127 — behind Koele, mountains of Lanai, Hawaiian
Islands.
Endodonta (Thaumatodon) ringens Sykes, 1900, Fauna Ha-
waiiensis, Moll., 2, (4), p. 288-289, pi. 11, figs. 39, 40 - in wet
forest above Pelekunu, Molokai, Hawaiian Islands.
Diagnosis. — Shell of average size, diameter 3.91-4.61 mm. (mean
4.14 mm.), with 5^-5'/2 whorls. Apex and early spire flat, body
whorl descending much more rapidly, H/D ratio 0.407-0.456 (mean
0.439). Umbilicus U-shaped, regularly decoiling, contained 3.05-3.60
times (mean 3.39) in the diameter. Apical sculpture absent on first
whorl, reduced in prominence on rest. Postnuclear whorls with high,
prominent, strongly protractive radial ribs, 41-70 (mean 51.2) on the
body whorl, whose interstices are 4-6 times their width. Micro-
sculpture of very fine radial riblets, eight to twelve between each
pair of major ribs, crossed by exceedingly fine microspirals visible
only under 96 X magnification. Sutures impressed, whorls strongly
rounded above and on basal margin, with evenly rounded outer
margin. Aperture subcircular, with evenly rounded outer margin,
inclined about 15° from the shell axis. Parietal barriers 2, extending
posteriorly three-sixteenths of a whorl, rarely with a short accessory
trace: upper very high and slender, weakly expanded on posterior
third, with gradual anterior descension; 2nd much lower posteriorly,
weakly expanded, with anterior half a raised threadlike ridge
extending beyond end of upper parietal. Columellar wall without
barriers. Palatal barriers 4, rarely 5, extending posteriorly about one-
eighth whorl, slightly recessed; lower at baso-columellar margin, a
thin, low crescentic blade; 2nd and 3rd high and bladelike, with
rather sharp anterior descension, weakly expanded above; 4th
supraperipheral, reduced in size, very thin, with more gradual
anterior descension; 5th, when present, located between 2nd and 3rd
palatal.
Description. — Shell of average size, with 5'4 moderately tightly
coiled whorls. Apex and early spire flat, last whorls descending
moderately, H/D ratio 0.452. Apical whorls 1%, first whorl smooth,
sculpture of fine, somewhat irregularly prominent radial ribs, very
216
SOLEM: ENDODONTOID LAND SNAILS
crowded, with a secondary sculpture of extremely fine spiral riblets
on remaining part. Postnuclear whorls with high, lamellate,
prominent, protractively sinuated radial ribs, 46 on the body whorl,
whose interstices are 4-fi times their width. Microsculpture of fine,
crowded radial riblets. moderately prominent, with a barely visible
sculpture of exceedingly fine and crowded spiral riblets. Color light
yellow-white with broad, prominent, zigzag, reddish flammulation,
fading out on shell base. Sutures deep, whorls strongly rounded
above, slightly flattened basally with evenly rounded periphery.
Umbilicus broadly U-shaped, slightly and regularly decoiling,
contained 3.50 times in the diameter. Aperture subcircular, somewhat
flattened basally. inclined about 15° from shell axis. Parietal barriers
2, extending three-sixteenths of a whorl: upper parietal with anterior
half gradually descending, becoming high, weakly expanded above
posteriorly, remaining thin for entire length; lower parietal with
anterior three-eighths low and threadlike, becoming moderately
elevated posteriorly, but much broader than upper parietal. Palatal
barriers 4, short, crescentic: lower a lamellate ridge located at baso-
columellar margin, nearly reaching lip; 2nd and 3rd much higher,
very slightly expanded above; upper palatal supraperipheral. slightly
recessed within aperture with more gradual anterior descension,
reduced in size, evenly rounded above. Height of lectotype 1.88 mm.,
diameter 4.15 mm.
Lectotype. — Hawaiian Islands: Lanai, behind
Koele. 1900.12.18.1374.
Range. — Lanai and possibly Molokai, Hawaiian
Islands.
Paratype. - BMNH 1900.12.18.1375.
Material. — Hawaiian Islands: Lanai (4 specimens,
BPBM 14329, BMNH 1900.12.18.1381-3); behind Koele
(2 specimens, BMNH 1900.12.18.1374-5). Molokai,
above Pelekunu (3 specimens, BMNH 1900.12.18.1366-
8).
Remarks. — The Molokai specimens that Sykes
(loc. cit.) reported as this species are much larger
(diameter 4.77-4.84 mm.), with a narrower umbilicus
(D/U ratio 3.67 - 4.14), and have the lower palatal
barrier almost shifted onto the columellar wall.
Whether they are taxonomically distinct from the
Lanai populations is unknown.
In form of shell and barriers, ringens shows many
similarities to contortus. It differs in its flat spire,
much more widely spaced radial ribs (mean ribs/mm.
3.92), and more slender barriers.
Cookeconcha elisae (Ancey, 1889)
Pitys elisae Ancey, 1889, Bull. Soc. Malacol. France, 6, p. 180 -
Sandwich Islands; Pilsbry, 1892, Man. Conchol., (2), 8, p. 95.
Endodonta elisae (Ancey), Pilsbry, 1893. Man. Conchol., (2). 9, p.
27; Caum, 1928, Bull. B. P. Bishop Museum.. 56, p. 65.
Helix (Pitys) elisae Ancey, Baldwin, 1893, Catalogue Land and
Fresh Water Shells, p. 16.
Endodonta (Nesophila) elisae (Ancey), Sykes, 1900, Fauna
Hawaiiensis, Moll. 2, (4), p. 290 - ? Hawaiian Islands.
Range. — Unknown, probably a Hawaiian species.
Material. — None.
Remarks. - Although Sykes (1900, p. 290) and
Caum (1928, p. 65) questioned that this was a
Hawaiian species, its status will remain uncertain until
the Hawaiian fauna is revised. The wide umbilicus,
rounded aperture, single parietal barrier, and the
presence of one or two columellar and/or palatal
barriers provide a character complex typically Ha-
waiian, but not usually duplicated on other islands of
the Pacific.
Cookeconcha luctiferus (Pilsbry & Vanatta,
1905). Figure 94d-f.
Endodonta (Thaumatodon) luctifera Pilsbry and Vanatta, 1905,
Proc. Acad. Nat. Sci., Philadelphia, 57, p. 575, p. 39, figs. 4, 5, 6
— Sandwich Islands.
Diagnosis. — Shell a little larger than average, diameter 3.91-
5.23 mm. (mean 4.51 mm.), with 47/» - 534 normally coiled whorls.
Apex and spire flat or depressed, last whorl descending much more
rapidly, H/D ratio 0.427-0.496 (mean 0.460). Umbilicus broadly V-
shaped, last whorl decoiling regularly or slightly more rapidly,
contained 2.96-4.19 times (mean 3.49) in the diameter. Apical
sculpture absent on first three-quarters whorl, typical on rest.
Postnuclear sculpture of narrow, prominent, strongly protractively
sinuated radial ribs, 42-60 (mean 51.0) on the body whorl, whose
interstices are 4-6 times their width. Microsculpture of fine radial
riblets, ten to fourteen between each pair of major ribs, crossed by
exceedingly fine and crowded spiral riblets. Suture impressed, whorls
strongly rounded above and on umbilical margin, evenly rounded on
outer margin, sometimes slightly flattened above periphery. Aperture
subcircular. inclined about 20° from shell axis. Parietal barriers 2,
extending posteriorly slightly less than one-quarter to more than
one-quarter whorl: upper a low lamellar ridge, barely to moderately
elevated on posterior third, not expanded above, with gradual
anterior descension; 2nd a low ridge, at most weakly elevated
posteriorly, anterior five-eighths threadlike, extending even with or
slightly in front of upper parietal termination. Columellar wall
frequently (22.2 per cent) with a moderately recessed, very short,
threadlike trace lying parallel to plane of coiling. Palatal wall with
1-4, usually 2 or 3, short, low, crescentic to threadlike barriers: lower
usually on basal margin, sometimes large, sometimes smaller than
2nd and 3rd, which may be crescentic. If 2nd and 3rd threadlike,
then lower lost. Occasionally a fourth supraperipheral trace can be
detected.
Holotype. - ANSP 58137.
Range. — Molokai, Hawaiian Islands.
Material. — Hawaiian Islands: Molokai (4 speci-
mens, FMNH 46255); Waikolu (1 specimen, FMNH
90618); Kamalo (4 specimens, FMNH 73194).
Remarks. — This species represents an inter-
mediate stage in barrier reduction. The types, from an
unknown locality, have only one or two palatal traces,
while the material available for this study has a larger
number of traces. Adequate population samples un-
doubtedly will show considerable variation in this
character.
Cookeconcha hystricellus (Pfeiffer, 1859). Figure
165j-k.
Helix hystricella Pfeiffer, 1859, Proc. Zool. Soc. London, 1859, p.
25 - Sandwich Islands; Pfeiffer, 1859, Malakol. Blatt., 6, p. 11;
Pfeiffer, 1868, Mon, helic. viv., 5. p. 221 - Kauai; Pfeiffer, 1876.
Mon, helic. viv., 7, p. 258.
Pitys hystricella (Pfeiffer). Pease, 1871, Proc. Zool. Soc. London,
1871, p. 474; Ancey, 1889, Bull. Soc. Malacol. France, 6, p. 183.
Patula (Endodonta) hystricella (Pfeiffer), Clessin, 1881, Nomen.
helic. viv., p. 96.
">.Helix (Pitys) hystricella Pfeiffer, Baldwin, 1893, Catalogue Land
and Fresh Water Shells, p. 16 - Kauai.
Endodonta (Thaumatodon) hystricella (Pfeiffer), Sykes, 1900,
Fauna Hawaiiensis, Moll., 2, (4). p. 288 — Kaala, Oahu,
Hawaiian Islands.
SYSTEMATIC REVIEW
217
^Endodonta hystriceUa (Pfeiffer), Ancey, 1904, Jour. Malacol., 11,
(4), p. 67 — Makawao, Maui, Hawaiian Islands.
Range. — Waianae Mountains, Oahu, Hawaiian
Islands.
Material. — Hawaiian Islands (1 specimen, FMNH
7642 ex Philip Carpenter): Oahu, Waianae Mts.,
Palehua (6 specimens, FMNH 116893); Popowela,
Waianae Mts. (4 specimens, FMNH 116894).
Remarks. — The identity of this unfigured species
is uncertain. Table LXXIV indicates the extent of
variation between populations that could be referred
to this name. Since no original material was available,
no diagnosis has been prepared. Probably neither
population will be referable to the eventually delin-
eated nominate race, but this is the most likely
named entity to use for these populations. I doubt
that the Maui shells referred to this species by Ancey
(loc. cit. ) are correctly identified.
Both populations used in this survey have 2
parietals, a weak to moderate supraperipheral sulcus, 3
or 4 rather deeply recessed, small palatals, a depressed
spire, and prominent color pattern. They differ widely
in size, umbilical width, and sculpture (table LXXIV).
Dissection of material from Popowela (BPBM 35421)
and Palehua (BPBM 35835) demonstrated marked
differences in penial pilaster patterns. At the present
time, I prefer not to assess the systematic significance
of these variations.
Description of soft parts. — Foot and tail long, tapering
posteriorly, truncated anteriorly. Sole undivided. Pedal grooves
rather low in foot, equally prominent, no caudal horn or middorsal
groove present. Slime network of very fine ovoid reticulations. Head
projecting in front of foot. Ommatophores typical. Gonopore above
front margin of foot, directly behind right rhinophore.
Body color yellow-white, no darker markings.
Mantle collar rather wide, no glandular extension onto pallial
roof. Pneumostome typical.
Pallial region about 5.6 mm. long. Lung roof clear, without
granulations. Kidney about 2 mm. long, broad basally, with short
(0.5 mm.) rectal arm. Ureter opening at anterior margin of kidney
rectal arm, typical in form. Heart about half length of kidney, lying
slightly off the hindgut axis. Principal pulmonary vein and hindgut
typical.
Ovotestis (fig. 165J, G) of palmately clavate alveoli in
overlapping clusters along a single collecting tubule, rather short,
early clumps perpendicular to sides of whorls, later slanted upward.
Hermaphroditic duct (GD) very narrow at first, only slightly-
expanded medially, narrowing and reflexing before entering carre-
four. Albumen gland (GG) small, irregular in shape. Talon (GT) with
bulbous head, tapering slowly to junction with carrefour (X), which
is buried in albumen gland and much smaller than head of talon.
Prostate (DG) with two to three rows of acini opening into a narrow-
tube. Uterus (UT) bipartite, extending only slightly below end of
prostate.
Vas deferens (VD) typical, weakly bound to penioviducal angle,
entering penis between pilasters (fig. 165k, EP), about 0.7 mm. below
apex, bound to side of penis for last 0.5 mm. of length. Penial
retractor (PR) arising from diaphragm at apex of penial cavity,
inserting directly onto head of penis. Penis (P) about 2.7-3.7 mm.
long, bulbous apically and in upper portion, tapering abruptly to
moderately below, internally (fig. 165k) with two large pilasters (PP),
united apically, one tapering shortly after the apex, the other grossly
expanded, bifolded and with bulbous termination. Atrium (Y) rather
short.
Free oviduct (UV) short, weakly demarcated from end of uterus.
Spermatheca (S) typical, shaft inserting slightly above junction of
penis and free oviduct, forming a very short vagina (V).
Free muscle system and digestive system not showing any
significant differences from Endodonta.
Jaw composed of narrow, overlapping, partly fused plates that
are not clearly enough separated to count, about 0.31 mm. long.
Radula with 9 or 10 laterals and 10 or 11 marginals, central
about 8fi wide and 13-14fi long. All basal plates very elongated,
marginals with square plates and only four or five equal cusps.
(Based on BPBM 35421, four whole and several fragmentary
examples.)
Cookeconcha stellulus (Gould, 1844). Figure 93
a-c.
Helix stellulus Gould, 1844, Proc. Bost. Soc. Nat. Hist., 1, p. 174 -
Sandwich Islands; Gould, 1846, Exped. Shells Reprint, p. 194;
Gould, 1852, U. S. Explor. Exped. "Wilkes," 12, pp. 56-57-Maui;
Pfeiffer, 1853, Mon. helic. viv., 3, p. 145; Pfeiffer, 1859, Mon.
helic. viv., 4, p. 156; Gould, 1860, U. S. Explor. Exped. "Wilkes,"
Atlas, pi. 4, fig. 52f, 52af, 52bf, 52cf; Pfeiffer, 1868, Mon. helic.
viv., 5, p. 222 Pfeiffer, 1876, Mon. helic. viv., 7, p. 260; Tryon,
1887, Man. Conchol., (2), 3, p. 61, pi. 11, figs. 84-86.
Pitys stellula (Gould), H. and A. Adams, 1858, Genera Recent
Moll., 2, p. 113; Pease, 1871, Proc. Zool. Soc. London, 1871, p.
474 - Maui; Ancey, 1889, Bull. Soc. Malacol. France, 6, p. 182.
Endodonta stellulus (Gould), von Martens, 1860, Die Heliceen, ed.
2, p. 90; Pilsbry, 1893, Man. Conchol., (2), 9, p. 27.
Patula (Endodonta) stellula (Gould), Clessin, 1881, Nomen. helic.
viv., p. 95.
Helix (Pitys) stellula (Gould), Baldwin, 1893, Catalogue Land and
Fresh Water Shells, p. 16; Johnson, 1964, Bull. U. S. Nat. Mus.,
239, p. 152, pi. 38, fig. 3.
Endodonta (Nesophila) stellula (Gould), Sykes, 1900, Fauna
Hawaiiensis, Moll., 2, (4), p. 291 — Maui.
Diagnosis. — Shell of average-to-large size, diameter 4.28-5.38
mm., with 4'4-5% normally coiled whorls. Apex and spire sunken
beneath level of body whorl, last whorl not descending, H/D ratio
0.369-0.394. Umbilicus cup-shaped, regularly decoiling, contained
3.10-3.15 times in the diameter, with angled basal margin. Apical
sculpture absent on first half whorl, reduced on remainder.
Postnuclear whorls with extremely high and prominent, protractively
sinuated radial ribs, 19 on the body whorl, whose interstices are 3-4
times their width, and which are curiously twisted on crossing the
protruded keels. Microsculpture of extremely fine radial riblets, more
than 12 between each pair of major ribs, crossed by barely visible
spiral riblets. Sutures deep on early spire, shallow on body whorl,
latter flat or slightly concave up to strongly rounded supraperipheral
keel, then flat down to deep supraperipheral sulcus, rising flatly to
protruded keel, followed by a deep and narrow subperipheral sulcus,
then flatly rounded down to strongly rounded basal margin.
Aperture subquadrangular, inclined about 25° from shell axis.
Parietal barriers 2, extending posteriorly one-quarter whorl: upper a
high, thin blade, slightly more elevated and weakly expanded on
posterior quarter, with gradual anterior descension; 2nd a very
inconspicuous, threadlike trace partly obscured by protrusion of the
very large radial ribs. Columellar wall without barriers. Palatal
barriers 3, deeply recessed, very small and inconspicuous: lower just
above sharp curve of basal margin, a short crescentic ridge extending
less than one-eighth whorl; 2nd a much shorter, threadlike trace
located midway between 1st palatal and outermost part of protruded
keel; 3rd equal in size to 2nd, located inside outermost part of
supraperipheral keel.
218
SOLEM: ENDODONTOID LAND SNAILS
Holotype. - Maui, Hawaiian Islands. MCZ 169383
ex New York State Museum 242.
Range. — Maui, Hawaiian Islands.
Paratype. - FMNH 155099.
Material. — Hawaiian Islands, Maui (2 specimens,
FMNH 155099, BMNH 42.2.21.63).
Remarks. — Casual inspection even with good
optical equipment could result in missing the lower
parietal and all the palatal barriers. Hence their
omission from Gould's original description is not
surprising. While Cookeconcha stellulus appears
strikingly different from the remaining Hawaiian
species, the alterations in whorl contour that give it
this unusual appearance are the same alterations seen
in the Mangarevan Gambiodonta mirabilis (fig. 188c-
d), except for lacking a basal keel (the result of brood
pouch formation in the Gambiodonta!), and in the
Fijian Thaumatodon spirrhymatum Solem (1973d). In
sculpture, barriers, general appearance and basic
shape, Cookeconcha stellulus clearly is related to C.
hystricellus. Unless anatomical peculiarities are
demonstrated, I doubt that even subgeneric separation
from C. hystricellus would be warranted. Since
populations of the latter show a weak-to-moderate
supraperipheral sulcus, the extensive development of
keels and sulci in C. stellulus should be viewed as an
elaboration of a trend, rather than set apart as a
unique occurrence. After completion of this section,
another specimen was located in the British Museum
(Natural History). Its dimensions have been added to
the diagnosis, but no average computed.
FIG. 93. Cookeconcha stellulus (Gould). Maui, Hawaiian Islands.
FMNH 155099. (MM).
Cookeconcha paucicostatus (Pease, 1870)
Pitys paucicostata Pease, 1870, Jour, de Conchyl., 18, p. 395 —
Kauai; Ancey, 1889, Bull. Soc. Malacol. France, 6, p. 184.
Pitys filicostata Pease, 1871, Proc. Zool. Soc. London, 1871, p. 454.
Helix paucicostata (Pease), Pfeiffer, 1876, Mon. helic. viv., 7, p.
261; Tryon, 1887, Man. Conchol., (2), 3, p. 60.
Patula (Endodonta) paucicostata (Pease), Clessin, 1881, Nomen.
helic. viv., p. 95.
Helix filicostata (Pease), Tryon, 1887, Man. Conchol., (2), 3, p. 60.
Helix (Pitys) paucicostata (Pease), Baldwin, 1893, Catalogue Land
and Fresh Water Shells, p. 16 - Kealia to Haena, Kauai.
Endodonta filicostata (Pease), Pilsbry, 1893, Man. Conchol., (2), 9,
p. 26.
Endodonta paucicostata (Pease), Pilsbry, 1893, Man. Conchol., (2),
9, p. 26.
Endodonta (Nesophila) paucicostata (Pease), Sykes, 1900, Fauna
Hawaiiensis, Moll., 2, (4), p. 291.
Range. — Kauai, Hawaiian Islands.
Material. — "Marquesas" (1 specimen, FMNH
46435, ex Webb, Gude, Ancey).
Remarks. — The single specimen, 3.06 mm. in
diameter with 4V&- whorls, although mislabelled as to
locality, is this unfigured species. The 2 weak parietal
SYSTEMATIC REVIEW
219
FIG. 94. a-c, Cookeconcha thaanumi (Pilsbry & Vanatta). Kaiwiki, Hilo, Hawaii, Hawaiian Islands. Holotype ANSP 89245; d-f,
Cookeconcha luctiferus (Pilsbry & Vanatta). "Sandwich Islands." Holotype. ANSP 58137. Copied from Pilsbry & Vanatta (1905, pi. 39) with
permission of the Academy of Natural Sciences, Philadelphia. Relabled for this use. Figures c and / incorrect in showing microradial ribs absent
from surface of major ribs and no indication of microspiral ribs.
barriers, very widely spaced radial ribs, 24 on the body
whorl with 2.50 ribs/mm., loss of sculpture on the first
part of the apex, umbilical shape and size (D/U ratio
3.88), plus the very low spire (H/D ratio 0.473), suggest
that this is derived from a type very close to
Cookeconcha luctiferus.
Cookeconcha paucilamellatus (Ancey, 1904)
Endodonta hystricella var. paiicilamel/ata Ancey, 1904, Jour.
Malacol.. 11, p. 67. pi. 5, fig. 17 — Palihoukapapa, Hamakua
slope of Mauna Kea. Hawaii, Hawaiian Islands.
Range. — Hawaii, Hawaiian Islands.
Material. — None.
Remarks. — The complete absence of palatal
barriers, wider and more regular radial ribs, and
apparently much narrower umbilicus serve to dis-
tinguish this form from the Oahu Cookeconcha
hystricellus.
Cookeconcha thaanumi (Pilsbry & Vanatta, 1905).
Figure 94a-c.
Endodonta thaanumi Pilsbry & Vanatta, 1905, Proc. Acad. Nat.
Sci.. Philadelphia, 57, pp. 574-575, pi. 39, figs. 1, 2, 3, - Kaiwiki,
near Hilo, Hawaii; Olaa, Hawaii; and Honokowai Gulch, West
Maui, Hawaiian Islands.
Diagnosis. — Shell large, diameter 4.44-5.53 mm. (mean 4.96
mm.), with 47/s-5'/2 normally coiled whorls. Apex flat or slightly
depressed, lower spire descending slightly, body whorl more rapidly,
H/D ratio 0.435-0.524 (mean 0.471). Umbilicus U-shaped, regularly
decoiling, contained 3.07-3.73 times (mean 3.39) in the diameter.
Apical sculpture absent nearly to end of apex. Postnuclear sculpture
of thin, prominent, strongly protractively sinuated radial ribs, 46-57
(mean 51.7) on the body whorl, whose interstices are 4-6 times their
width. Microsculpture of very fine radial riblets, eight to twelve
between each pair of major ribs, with barely visible, extremely
crowded spiral ribbing visible under 96 x magnification. Sutures
impressed, whorls strongly rounded above and on basal margin,
slightly compressed laterally above and below rounded periphery.
Aperture subcircular, compressed laterally above and below rounded
periphery, inclined about 20° from shell axis. Parietal banners 2,_
extending posteriorly less than one-quarter whorl: upper threadlike
to moderately elevated, not expanded above, extending posteriorly
three-sixteenths to one-quarter whorl; lower threadlike for entire
220
SOLEM: ENDODONTOID LAND SNAILS
length, extending slightly further anteriorly. Columellar and palatal
walls without barriers.
Types. - Kaiwiki, Hilo, Hawaii, Hawaiian Islands.
ANSP 89245.
Range. — Reported from Molokai, Maui and
Hawaii, Hawaiian Islands.
Material. - Hawaiian Islands: Molokai (4 speci-
mens, FMNH 46237); Kaluaaha, Molokai (2 specimens,
FMNH 73193).
Remarks. - Careful analysis of shape and sculp-
tural variation will be required before the reported
range of Cookeconcha thaanumi can be accepted or
rejected. Differences from the other described species
with 2 parietals and without palatals are simple: C.
hystrix has undulating sculpture and a markedly
hirsute periostracum, while C. paucicostatus has much
fewer and more widely spaced ribs, is much smaller,
and has a narrower umbilicus (table LXXIV). The
other species have only a single parietal.
Cookeconcha hystrix (Pfeiffer, 1846)
Helix hystrix "Mighels" Pfeiffer, 1846, Symb. ad. hist. Heliceorum,
3, (5), pp. 67-68 - Hawaiian Islands; Pfeiffer, 1848, Mon. helic.
viv., 1, p. 116 — Wahoo (= Oahu), Hawaiian Islands; Pfeiffer.
1852, Syst. Conchyl. Cab., 12, (2), p. 132, pi. 89, figs. 8-11, (plate
issued 1850); Gould, 1852, U. S. Explor. Exped. "Wilkes," 12, pp.
55-56 - East Maui (probably a different species); Pfeiffer, 1853,
Mon. helic. viv., 3, p. 145; Reeve, 1854, Conchol. Icon., Helix, pi.
133, fig. 655; Pfeiffer, 1859, Mon. helic. viv., 4, p. 156; Gould,
1860, U. S. Explor. Exped. "Wilkes," Exped. Shells, Atlas, pi. 4.
fig. 52*, 52b*, 52c*; Pfeiffer, 1868, Mon. helic. viv., 5, p. 222;
Pfeiffer, 1876, Mon. helic. viv., 7, p. 261; Tryon. 1887, Man.
Conchol., Philadelphia, 3, p. 59, pi. 11, figs. 71-73; Johnson, 1949,
Occ. Pap. Moll., 1, (14), p. 225.
Helix setigera Gould, 1844 (not Sowerby, 1841), Proc. Boston Soc.
Nat. Hist., 1, p. 174.
Patula hystrix (Pfeiffer), Albers, 1850, Die Heliceen, p. 65; von
Martens, 1860, Die Heliceen, ed. 2, p. 90.
Pitys hystrix (Pfeiffer), H. & A. Adams, 1858, Genera Recent Moll.,
2, p. 113; Pease, 1871, Proc. Zool. Soc. London, 1871, p. 471 -
Oahu; Ancey, 1889, Bull. Soc. Malacol. France, 6, pp. 182-183.
Patula (Endodonta) hystrix (Pfeiffer), Clessin, 1881, Nomen. helic.
viv., p. 95 — Sandwich Islands.
Helix (Pitys) hystrix Mighels, Baldwin, 1893, Catalogue Land and
Fresh Water Shells, p. 16 — Maui, Oahu, and Kauai.
Endodonta hystrix (Pfeiffer), Pilsbry, 1893, Man. Conchol., (2). 9,
Endodonta (Xesophila) hystrix (Pfeiffer), Sykes, 1900, Fauna
Hawaiiensis, Moll., 2, (4), p. 290 - Mt. Kaala, Oahu, Hawaiian
Islands.
Diagnosis. — Shell very large, diameter 4.61-6.27 mm. (mean 5.32
mm.), with 4%-5V8 normally coiled whorls. Apex and early spire
sunken, later whorls descending rapidly, H/D ratio 0.431-0.577 (mean
0.475). Umbilicus broadly open. V-shaped, regularly decoiling,
contained 2.63-3.94 times (mean 2.94) in the diameter. Apical
sculpture absent for most of first whorl, typical near end. Post-
nuclear whorls with high, very prominent, strongly protractively
sinuated radial ribs, 31-70 (mean 41.3) on the body whorl, whose
interstices are 3-5 times their width, some populations having the
tops of major ribs with long periostracal hairs arranged in spiral
rows, the hair "pits" giving a wavy, undulating effect to the
sculpture. Microsculpture of fine radial riblets, eight to twelve
between each pair of major ribs, crossed by extremely fine and
crowded spiral riblets. Sutures deep, whorls strongly rounded above
and on basal margin, either flattened laterally above and below
rounded periphery or with evenly rounded outer margin. Aperture
subcircular, with rounded or variously flattened outer margins,
inclined about 25° from shell axis. Parietal barriers 2, lower rarely-
absent, extending posteriorly slightly less than one-quarter whorl:
upper threadlike for entire length or weakly elevated posteriorly;
lower threadlike, anterior end slightly in front of upper.
Description (of setigera). — Shell of average size, with slightly
less than 4'/i normally coiled whorls. Apex and first two post-nuclear
whorls sunken below top of body whorl, latter portion of body whorl
descending slightly. H/D ratio 0.430. Apical whorls l'<6, sculpture of
very fine radial riblets on last part, partially obscured by fungus.
Postnuclear whorls with high, prominent, protractively sinuated,
somewhat nodose radial ribs, 32 on the body whorl, whose interstices
are 2-4 times their width. Microsculpture of relatively prominent
radial riblets, crossed by barely visible, much finer and more crowded
spiral riblets. Sutures deep, whorls slightly shouldered above with
rounded outer margin, slightly flattened laterally below periphery
and on columellar margin. Color yellowish-white with broad, zigzag,
reddish flammulations, seven on the body whorl, that become very
thin and attenuated below periphery. Umbilicus broadly open, U-
shaped, regularly and slightly decoiling, contained 3.37 times in the
diameter. Aperture subovate, slightly compressed laterally below
periphery and on columellar margin, inclined about 30° from the
shell axis. Parietal wall with 2 low, threadlike barriers, extending
three-sixteenths of a whorl, the upper slightly more prominent, and a
faint suggestion of an upper parietal trace. Columellar and palatal
walls without barriers. Height of holotype 1.91 mm., diameter 4.44
mm.
Lectotype. — Sandwich Islands (= Hawaii).
Collected by United States Exploring Expedition.
USNM 5453.
Material. — Hawaiian Islands (19 specimens,
FMNH 46444, FMNH 91151, FMNH 91890, FMNH
117045): Oahu, Konahuanui (1 specimen, FMNH
116895); Helemanu (1 specimen, FMNH 116896);
Palikea, Waianae Mts. (25 specimens, FMNH 53043,
FMNH 111527).
Remarks. — The lectotype of Helix setigera
Gould, 1844 (not Sowerby, 1841) is juvenile. A
specimen mislabelled as "type" of Helix rubiginosa
Gould, 1846 is this species. The nuclear whorls of the
former are larger (0.46 mm. wide compared with 0.36
mm.) and the radial ribs more widely spaced (2.29
ribs/mm, in setigera, 3.21 ribs/mm, in the other).
Probably several species are confused under this
name, and Cookeconcha hystrix should be restricted to
the very large, hirsute population found on Mt.
Konahuanui. The shells from East Maui with small
palatal barriers reported by Gould (1852, p. 56)
probably are related to C. hystricellus and not to C.
hystrix. Specimens from the Mt. Konahuanui popu-
lation were dissected. As mentioned above, specimens
from Helemanu that were conchologically referred to
as hystrix showed differences in penial pilaster pattern
that might indicate specific separation. More studies
are needed, before the many Oahu forms of this type
can be classified with certainty.
Description of soft parts. — Only differences from the material
of C. hystricellus are noted. Kidney longer and more slender with the
rectal arm equal to half of length. Lobes of ovotestis larger, talon
much more slender and free oviduct proportionately a little longer.
SYSTEMATIC REVIEW
221
Vagina absent, since spermatheca inserts on oviducal side of
penioviducal angle. Penis about 3.95 mm. long, not as expanded and
contracting near atrium rather than tapering, internally with similar
pilasters, except both are narrower, with greater free edges and much
longer. Larger of two pilasters (which unite apically) comes to a
bluntly tapered end about five-eighths of way down length of penis.
In C. hystricellus, the larger pilaster comes to a globosely rounded,
abrupt termination about three-eighths of way from penial apex. No
other significant differences could be found.
(Based on BPBM 17607, three examples.)
Cookeconcha decussatulus (Pease, 1866)
Helix decussatula Pease, 1866, Amer. Jour. Conchol., 2, p. 291 —
Sandwich Islands; Pfeiffer, 1876, Mon. helic. viv., 7, p. 261;
Tryon, 1887, Man. Conchol., (2), 3, p. 60.
Pitys decussatula (Pease), Pease, 1871, Proc. Zool. Soc. London,
1871, p. 474 - Molokai; Ancey, 1889, Bull. Soc. Malacol.
France, 6, pp. 184-185.
Patula (Endodonta) decussatula (Pease), Clessin, 1881, Nomen.
Helic. viv., p. 95.
Helix (Pitys) decussatula Pease, Baldwin, 1893, Catalogue Land
and Fresh Water Shells, p. 16 — Wahiawa and Waimea, Kauai.
Endodonta decussatula (Pease), Pilsbry, 1893, Man. Conchol., (2),
9, p. 27.
Endodonta (Nesophila) decussatula (Pease), Sykes, 1900, Fauna
Hawaiiensis, Moll., 2, (4), p. 290 - Mountains at 4,000 ft.,
Molokai, Hawaiian Islands.
Diagnosis. — Shell slightly smaller than average, diameter 3.49-
4.28 mm. (mean 3.76 mm.), with 4V6 - 4% normally coiled whorls.
Apex and spire flat or barely elevated, last whorl descending slightly
more rapidly, H/D ratio 0.364-0.405 (mean 0.389). Umbilicus broadly-
open, V-shaped, regularly dec-oiling, contained 3.02-3.42 times (mean
3.25) in the diameter. Apical sculpture absent on first whorl, greatly
reduced on rest. Postnuclear whorls with low, V-shaped, strongly
protractive radial ribs, 60-74 (mean 67.8) on the body whorl, whose
interstices are 2-4 times their width. Microsculpture of rather large
radial riblets, five to eight between each pair of major ribs, crossed
by extremely fine and crowded spiral riblets that are barely visible
under 96X magnification, with a secondary sculpture of narrow
spiral cords that are most crowded near periphery and most widely
spaced on shell base. Secondary spiral cords quite narrow, almost V-
shaped. Sutures impressed, whorls flatly rounded above and on basal
margin, strongly and evenly rounded on outer margin. Aperture
subcircular, flattened above and below evenly rounded periphery,
inclined about 25° from shell axis. Parietal wall with single
supramedial, low, bladelike barrier, extending posteriorly to line of
vision, with gradual anterior descension.
Range. — Maui and Molokai, Hawaiian Islands.
Material. — Hawaiian Islands: Maui, western part
(2 specimens, FMNH 46605); Homokowai (sic) Gulch
(3 specimens, AMS C37190 ex Hedley, Preston);
Hokokoupi Gulch (1 specimen, FMNH 90636).
Remarks. — The secondary spiral cording and
much smaller size combine to separate Cookeconcha
decussatulus from either C. jugosus or C. lanaiensis,
the other named forms with only a single parietal. The
latter is very similar in general appearance and may be
only subspecifically separable when adequate material
has been examined.
Cookeconcha lanaiensis (Sykes, 1896)
Endodonta (Nesophila) lanaiensis Sykes, 1896, Proc. Malacol.
Soc. London, 2, (3), p. 127 — behind Koele, Mountains of Lanai,
Hawaiian Islands; Sykes, 1900, Fauna Hawaiiensis, Moll., 2, (4),
p. 291, pi. 11, figs. 37, 38 — ?Makaweli, Kauai. Hawaiian Islands.
Endodonta lanaiensis (Sykes), Ancey, 1904, Jour. Malacol., 11, p.
67 — Palihoukapapa, Hamakua slope of Mauna Kea, Hawaii,
Hawaiian Islands.
Diagnosis. — Shell larger than average, diameter 4.24-5.10 mm.
(mean 4.72 mm.), with 4'/2 - 434 normally coiled whorls. Apex and
spire flat or slightly depressed, last whorl descending slightly, H/D
ratio 0.354-0.414 (mean 0.374). Umbilicus broadly open, V-shaped,
regularly decoiling, contained 2.98-3.45 times (mean 3.23) in the
diameter. Apical sculpture absent from first whorl, very faint on rest
of apex. Postnuclear sculpture of broad, low, protractively sinuated
radial ribs, 50-72 (mean 64.3) on the body whorl, whose interstices
are 2-4 times their width. Microsculpture of rather large radial
riblets, five to eight between each pair of major ribs, crossed by
extremely fine and crowded spiral riblets. Sutures impressed, whorls
flatly rounded above and below strongly rounded periphery.
Aperture ovate, inclined about 30° from shell axis. Parietal wall
usually with a single, supramedial, raised threadlike ridge, extending
posteriorly to line of vision, sometimes with a very inconspicuous
lower accessory threadlike trace. Columellar and palatal walls
without banners.
Description. — Shell larger than average, with slightly less than
434 normally coiled whorls. Apex and early spire flat, later whorls
descending moderately, H/D ratio 0.414. Apical whorls 1%, smooth
at first, sculpture of fine, crowded radial ribs, whose interstices are
less than twice their width, with a barely visible secondary sculpture
of crowded spiral riblets. Postnuclear whorls with high, broadly
rounded, irregularly sinuated, strongly protractive radial ribs, about
66 on the body whorl, whose interstices are 2-4 times their width.
Major ribs varying greatly in width, often with a knob-like
appearance at nearly regular intervals. Microsculpture of prominent,
relatively crowded, sinuated radial riblets crossed by extremely fine
and crowded spiral riblets. Color light yellowish-white with zigzag,
narrow, reddish flammulations. Sutures deep, whorls strongly
rounded above, flattened laterally above evenly rounded periphery
and on basal margin. Umbilicus V-shaped, widely open, regularly
decoiling, contained 3.45 times in the diameter. Periphery of whorl
slightly angulated. Aperture ovate, slightly flattened above periphery
and on basal margin, inclined about 25° from shell axis. Parietal
barriers 2: upper a moderately elevated, ridgelike lamella, extending
more than one-quarter whorl and supramedial in position; lower
parietal an inconspicuous, threadlike ridge parallel to the upper and
slightly submedial in position. No columellar or palatal barriers.
Height of holotype 1.97 mm., diameter 4.77 mm.
Holotype. — Hawaiian Islands: Lanai, Mountains
behind Koele. BMNH 1900.12.18.1521.
Range. — Lanai, possibly Hawaii and Kauai,
Hawaiian Islands.
Paratypes. - BMNH 1900.12.18.1376-80.
Material. — Hawaiian Islands: Lanai (1 specimen,
BPBM 14234); mountains behind Koele (6 specimens,
BMNH 1900.12.18.1521, BMNH 1900.12.18.1376-80).
Remarks. — The single adult of several specimens
from Kauai (BMNH 1900.12.18.1396-1406) that Sykes
(1900, p. 291) referred to this species differs in rib
count (83), whorls (5'/4-) and D/U ratio (3.87). I
suspect it is specifically distinct. The holotype is the
only example with a 2nd parietal trace.
Cookeconcha jugosus (Mighels, 1845). Figure
165h-i.
Helix jugosa Mighels, 1845, Proc. Boston Soc. Nat. Hist., 2, p. 19
- Waioli, Kauai, Hawaiian Islands; Pfeiffer, 1848, Mon. helic;
viv., 1, p. 188; Pfeiffer, 1853, Mon. helic. viv., 3, p. 145; Pfeiffer,
1859, Mon. helic. viv., 4, p. 156; Pfeiffer, 1868, Mon. helic. viv., 5,
222
SOLEM: ENDODONTOID LAND SNAILS
p. 222; Pease, 1871, Jour, de Conchyl., 19, pp. 95-96; Pfeiffer,
1876, Mon. helic. viv., 7, p. 266; Pfeiffer, 1877, Syst. Conchyl.
Cab., (1), 12, (4). p. 554, pi. 166, fig. 19-21; Tryon, 1887, Man.
Conchol., (2), 3, p. 59, pi. 11, fig. 65-68; Johnson, 1949, Occ. Pap.
Moll., 1, (14), p. 226.
Helix ntbiginosa Gould, 1846, Proc. Bost. Soc. Nat. Hist., 2, p.
173; Gould, 1846, Exped. Shells, Reprint, p. 21 - Kauai; Pfeiffer,
1848, Mon. helic. viv., 1, p. 187; Gould, 1852, U. S. Explor.
Exped. "Wilkes," 12, pp. 50-51 - Kauai; Pfeiffer, 1853, Mon.
helic. viv., 3, p. 145; Pfeiffer, 1859, Mon. helic. viv., 4, p. 156;
Gould, 1860, U. S. Explor. Exped. "Wilkes," Atlas, pi. 4. fig. 49,
49a, 49b, 49c; Pfeiffer, 1868, Mon. helic. viv., 5, p. 222; Pfeiffer,
1876, Mon. helic. viv., 7, p. 266; Johnson, 1964, Bull. U. S. Nat.
Mus.,239, p. 143.
Endodonta jugosa (Mighels), Albers, 1850, Die Heliceen, p. 89; von
Martens, 1860, Die Heliceen, ed. 2, p. 90; Pilsbry, 1893, Man.
Conchol., (2), 9, p. 27.
Endodonta rubiginosa (Gould), Albers, 1850, Die Heliceen, p. 89;
von Martens, 1860, Die Heliceen, ed. 2, p. 90.
Pitys jugosa (Mighels), H. & A. Adams, 1858, Genera Recent Moll.,
2, p. 113; Pease, 1871, Proc. Zool. Soc. London, 1871, pp. 452,
474 - Kauai; Ancey, 1889, Bull. Soc. Malacol. France, 6, p. 178.
Pitys rubiginosa (Gould), H. & A. Adams, 1858, Genera Recent
Moll., 2, p. 114; Ancey, 1889, Bull. Soc. Malacol. France, 6, p.
179 - Kauai and Oahu (?).
Patula (Endodonta) jugosa (Mighels), Clessin, 1881, Nomen. Helic.
viv., p. 94.
Helix (Endodonta) jugosa Mighels var. rubiginosa Gould, Clessin,
1881, Nomen. Helic. viv., p. 95; Tryon, 1887, Man. Conchol., (2),
3, p. 59, pi. 11, figs. 68-70.
Helix (Pitys) jugosa Mighels, Baldwin, 1893, Catalogue Land and
Fresh Water Shells, p. 16— Waioli and Kapaa, Kauai.
fHelix (Pitys) rubiginosa Gould, Baldwin, 1893, Catalogue Land
and Fresh Water Shells, p. 16 — Waianae Mts., Oahu.
Endodonta (Nesophila) jugosa (Mighels), Sykes, 1900, Fauna
Hawaiiensis, Moll., 2, (4), p. 290 — Waioli to Kapaa, Kauai.
Diagnosis. — Shell very large, diameter 5.26-7.37 mm. (mean 6.18
mm.), with 4% - 5% normally coiled whorls. Apex and early spire flat
to moderately elevated, last whorls descending distinctly more
rapidly. H/D ratio 0.390-0.521 (mean 0.450). Umbilicus widely open,
V-shaped, regularly decoiling, contained 2.38-3.20 times (mean 2.66)
in the diameter. Apex with sculpture absent on first whorl, reduced
on remainder. Postnuclear sculpture of low, narrow, strongly
protractively sinuated radial ribs, 47-80 (mean 62.0) on the body
whorl, whose interstices are 3-5 times their width. Microsculpture of
very fine radial riblets, five to eight between each pair of major ribs,
with spiral riblets that are barely visible under 96 X magnification.
Sutures impressed, whorls with evenly rounded outer margins.
Aperture circular, inclined about 25° from shell axis. Parietal wall
with a single medial or slightly supramedial, raised, threadlike ridge,
sometimes slightly elevated posteriorly, not expanded above, that
extends almost one-quarter whorl posteriorly. Columellar and
palatal walls without barriers.
Range. — Kauai, Hawaiian Islands.
Material. — Hawaiian Islands: Kauai, Milolii (1
specimen, FMNH 116900); north fork Wailua River (2
specimens, FMNH 116898 ex BPBM 81197); Kapaa (6
specimens, FMNH 117043); Haena (1 specimen,
FMNH 116897); Kapiliwahine, east of Wahiawa dam
(7 specimens, FMNH 116899).
Remarks. - A specimen in the United States
National Museum (USNM 5449) that I had thought
might be a type of Helix rubiginosa Gould, 1846 and
that Johnson (1964, p. 143) listed as the "holotype" is
a mislabeled example of Cookeconcha hystrix with 2
parietals and remnants of the periostracal hair pits. It
is quite different from Gould's (loc. cit.) type figures,
and is not at all similar in sculpture to the specimens
known under this name. While Johnson's holoytpe
"designation" switches the name rubiginosa to the
synonymy of hystrix, and possibly would replace the
latter, since both names were proposed in 1846, all the
references listed above are to the original concept of
the name rubiginosa. Nomenclatural quibbling would
require a transfer of names and references, plus
dredging historical records to establish the relative
priority of hystrix and rubiginosa. No scientific utility
would be served by such a procedure, and I strongly
recommend that the historical usage of these names be
continued.
Local populations show marked variation in spire
height and umbilical width (table LXXIV), but
whether this is indicative of subspeciation remains to
be determined. Dissections are based on specimens
from the north fork of the Wailua River. These shells
are quite large and have a relatively elevated spire.
Other named Hawaiian species with only 1
parietal barrier differ in having secondary spiral
sculpture (decussatulus) or in being much more
depressed with a narrower umbilicus (lanaiensis).
Description of soft parts. — Foot and tail about equal in length
to shell diameter. Sole undivided. Pedal grooves sharply defined,
relatively high on foot, no caudal horn or mid-dorsal groove present.
Slime network strongly demarcated, with irregularly ovate divisions,
varying greatly in size. Head at least partly retracted in all available
examples. Ommatophores typical. Gonopore position not determined.
Body color yellow-white, without darker markings.
Mantle collar with thickened edge, no glandular extension onto
pallial roof. Pneumostome and anus in typical position.
Pallial region about 9.5-11 mm. long. Lung roof clear, without
granulations. Kidney about 4.2 mm. long, rectal arm slightly less
than half total length, rounded posteriorly and extending over loop
of intestine. Ureter typical, slightly reflexed along weak rectal
extension, opening at rectal arm of kidney termination next to
hindgut. Heart about 1.6 mm. long, lying parallel to hindgut.
Principal pulmonary vein typical, fading out before mantle collar.
Hindgut typical, following parietal-palatal margin about one-eighth
whorl above apex of pallial cavity.
Ovotestis (fig. 165h, G) of numerous clumps of palmately clavate
alveoli, overlapping along a single collecting tubule, first few clumps
lying perpendicular to plane of coiling, more apical clumps lying at a
lesser angle than in E. fricki. Hermaphroditic duct (GD) slightly to
moderately convoluted medially, very narrow at either end, reflexing
slightly before entering carrefour (X). Albumen gland (GG) relatively
larger than in Nesophila tiara, but still rather small. Talon (GT)
large, finger-like, not tapered basally, but sharply constricted before
entering carrefour. Latter oval, tapering into shaft after entrance of
hermaphroditic duct prior to splitting into prostatic and uterine
ducts. Prostate (DG) typical, two or three rows of large acini opening
into a narrow tube. Uterus (UT) bipartite, lower expanded chamber
extending below end of prostate.
Vas deferens (VD) typical, lightly bound to penioviducal angle,
entering penis about 1 mm. below apex of penis, with penial pore
lying outside pilaster ring, but near to edge of one pilaster. Penial
retractor (PR) inserting directly on head of penis, arising from
diaphragm at apex of pallial cavity. Penis (P) moderately twisted in
partly retracted individuals, about 3.5-4.0 mm. long, not tapered
until just before base, internally (fig. 1651) with two large, rounded,
hemispherical pilasters united at apex, either united (as in figured
example) or tapering off basally. Atrium (Y) short, but a distinct
region.
u
o
•O
1
I
o
•a
&
o
a
s
^
«> E 5
u> ui
CO
(N <£
•*f •*
i
•f
CD
) +
i
]
^H t,
i
T
< i
rH rH rH
2 2
rH rH
•-1
rH
0 ^ rH rH r-
< rH
rH
rHl
CO CO
1
O
•"•tl o
I 1
0 0 r~(l
CO CO
CO
1 -+- CO CO C*
) + + '
CO
CO *^|
co co o
1
CM
CO
•* ^
a
at
co" c?
10 CM
fo
0
t- CO C- t- t
O t— Ol CJ C
to oo to
1 CO O CO
IO IO
CO*
U
oo" V co* V c
J CN CM CO*
1 I
1
1
I 1 1 1
i I 1
rH Cn
CO
CO
•^C C- rH CD O
•) to CN CO
Cn O
IO
C~- O5 CO OO C
> rH C- -^
10
co' V
CO
rH
U3 CM CO CO C
4 CN rH CN
&? *3f
rH
'
O^ t^ C^ rH* C
1 CM U3 CO
co e-
CO
CM
rH CD CO rH O
•> CM O 0
*** "***
IO
CO
t- CO CO -^ C
a CM rH CO
CM
So
oo
f^ 9 9
CO* *-x
oo -^ -^
"•**x OO
IO
IO
"•N. rH CO
rH "-^s.
IO ^
oo
10
10 CO IO CO* Q
? CO ^ ^
i
IO I 1 1
I CO ^-^
CO rH
t-
I OO CO CN 0
3 •* 1 rH
^ IO
10
rH
oo "^ "••^. ^ "**
••*X rH i-H i-f U
j ^j _£* to
1
•4< oo
IO
IO
00 IO IO vo u
3 IO *~* OO
•T "*
oo
Ol
i2- i 'T' V
CN oo co ••qh o
" T S- ^
3 TC 09
V,.
1 —
^ ^^ "^ >O
1-1 V
CO
rH
rH IO CO CO C
- 09 t- •**
IO IO
10
10
IO IO IO tO U
3 U3 IO CO
rH 0
CO CO
C— CO
0
09
IO
0
CM
CO
10 -^ co c- u
t- CO rH O C
CO CO CO CD U
3 -* rH -*
3 co oo en
3 10 •>»! IO
0 0
0
0
O O O O C
3 O O O
1 t
till
1 1 1
SIO
en
i
IO
IO
O »O t- rH C
CO O CO »O 0
0 CO CO OO
3 CO IO O
CO IO
IO
co 10 10 10 ••«
C ^ CO IO
0 0
o
o
o o o o c
3 O O O
rH rH
If
t-
?¥ ? -if i
> rH CO ->C
C- CO
IO
IO
IO IO iO T
C IO •«)> 10
o o
0
0
0 0 0 0 C
3000
CO <7>
0 CO
CO
en
rH 00 00 *^ U
O O> CD CD »-
3 CM e- •*
•i 1O t- 09
CO CO
CO
CO
**^* CO CO CO C
3 CO CO -^
1 1
1
1 I t 1
co en
CO
CO
rH CO U3 -^ U
3 CO OO CM
CO 0
0
CO
CO O rH IO C
3 co en c-
CM CO
CO
CM
CO CO CO CO C
0 Ol CM CO
OS" E^
»
«
t"" CO CN O r
? IH" co' of
09 01
CO
rH
t- U3 CO CO r
H CM CO CO
CM CO
CO
CO
CO CO CO CO C
0 CO CO -^
CO CM
c—
00
09
Ol O O> OJ C
CO CO rH rH U
b 00 CO CO
3 00 CO E-
01 Ol
1
rH
rH CN <N O4 r
H rH rH Ol
I 1
I
I I I I
1 1 1
C- CO
9
rH
CO
O> tO CJi CT> C
rH IO CD OJ •*«
0 00 CO rH
^ CO rH O
S" S"
is'
^j-
o' ^T O O ^
f ¥ to t?
o o
t-
09
CO O> C7> rH U
3 CO •* CO
CM CM
•-1
•-1
rH rH rH CN r
^ rH rH CM
« C?
C? ^-v CO* ^-N ^
-» ^~. --, o"
Cft I
en
rH OO rH 00 0
5 t- OO rH
1 C-
i
i 1 1 '
s a
o
c-
IO
10
ga» o co o
•^ or* t- c
9 rH •* 0
t- 1O f
rH"
00
co (?T to o c
) t~ CO Ol
§ §
rH
c-
rH
CO
SO CO C- r
CO O C- 0
rH rH
^ co •* •*
3 C— CO OO
s »
rH
CO
CM
rH
IO O Od lO U
O» rH r
t-
3 •* rH CO
H rH IN CO
rH
•jS -
CT)
js a
O- 4)
H
O "rt
3 3
1) O
altlaplca
caliculata
bltridentata
perahuensls
S « 2
S a 5 J
ss ^ E ;
•cH fa "a """i '
gfl S H c
3] U 4) U '
S <TJ rt tr) ;
11 S 3 S ^
i * 3 i
111
111
' g g a
il E E •§
CO
+
CO
IO
CO*
CO
^
IO
CO
10°
IO
rH
CO
IT-
CO
10
CM*
U
D
Q
I
<l
si
223
224
SOLEM: ENDODONTOID LAND SNAILS
Free oviduct (UV) quite short, indistinctly demarcated from
terminal section of uterus. Spermatheca (S) with elongately oval
head in normal position, lower part of shaft sometimes expanded,
inserting just on oviducal side of penioviducal angle. Vagina (V) not
effectively present as a distinct morphologic zone.
Free muscle system and digestive system as in Endodonta and
Nesophila.
Jaw of many narrow, partly fused, overlapping plates, too
indistinct to count, about 0.41 mm. long.
Radula with 14 laterals and many more than 8 marginals,
central about 6ju wide and 14^ long. Basal plates of marginals square,
four or five almost equal cusps.
(Based on BPBM 81197, several whole and partly broken
examples.)
Genus Kleokyphus, new genus
Large Endodontidae with a narrow, U-shaped umbilicus, more
than 7 tightly coiled whorls, a dome-shaped spire, 3-4 large parietals
and 4-5 large palatals. Sutures shallow to deep, body whorl obtusely
angulated to laterally compressed, aperture inclined 20-25° from
shell axis. Apical sculpture typical of subfamily, postnuclear major
sculpture prominent (?) to greatly reduced above periphery.
Anatomy unknown.
Type species. — Kleokyphus callimus, new species.
The size and form of the parietal and palatal
barriers is essentially the same as in Mautodontha
boraborensis and M. zimmermani. The narrow um-
bilicus, many whorls, and very large size of the two
Kleokyphus immediately separate them from Mau-
todontha. Very few Mautodontha have 4 parietals and
5 palatals. In M. daedalea, also known from Makatea,
the barriers are very reduced in size, the spire is
depressed and the umbilicus wide and shallow (fig.
73d). The form of the umbilicus in K. hypsus recalls
that of Mautodontha (Garrettoconcha) consobrina,
but the differences in whorls and barriers are too great
for the species to be congeneric.
Kleokyphus and Mautodontha probably evolved
from a single stock, but the former has developed more
specialized barriers, more and tighter coiled whorls (cf.
tables LXV, LXVI, and LXXV), a narrower umbilicus
that apically may be wider than below, and altered
sculpture in the one species where this is known with
certainty. The structural gap between Kleokyphus and
any Mautodontha is much greater than the gaps that
exist between species within Mautodontha. Kleokyphus
is another experiment towards the brood chamber level
of specialization.
The single specimen of K. hypsus has no trace of
sculpture left on the upper surface. On the shell base a
few obscure rugosities suggest that it has typically
developed radial sculpture, but this cannot be deter-
mined with any certainty. The sculpture of K.
callimus is remarkable. After typical endodontid apical
sculpture, a pattern of major radials begins, quickly is
reduced in prominence, and by the end of the first
post-nuclear whorls, the "major" ribs are no wider
than the microradials. The major ribs remain slightly
elevated and in strong lateral lighting can be dis-
tinguished. They are very widely spaced, but it proved
impossible to make an accurate count of the "major"
ribs. Just below the obtusely angulated periphery, a
nearly normal pattern of ribbing is seen, with the
major radials being several times the size of the
microradials and having an obvious secondary sculp-
ture of spiral cording.
The specimen that Aubert de la Rue and Soyer
(1958, p. 365) identified as "Endodonta daedalea" may
belong to a third species or may be a young example of
K. hypsus. The specimen was 1.35 mm. high, diameter
3.78 mm., with 4'/4- whorls, H/D ratio 0.547, D/U ratio
3.00, with about 110 ribs on the body whorl, 3 parietals
and 4 palatals. Unfortunately, it broke during an
attempt to clean the aperture. The wide umbilicus
suggests Mautodontha daedalea, but the great shell
elevation and different ribbing argue against this. The
main reason against considering that it was a juvenile
K. hypsus is the wide umbilicus. Without more
material, its identity will remain uncertain.
The occurrence of two endemic genera,
Kleokyphus and Pseudolibera, on Makatea is one of
the most unexpected results of this study. The name
Kleokyphus, from the Greek words for report (kleos)
and humpbacked (kyphos), was chosen to emphasize
the domed shape of these species and the remarkable
nature of this find.
Kleokyphus callimus, new species. Figure 95a-c.
Libera heynemanni Aubert de la Rue & Soyer, 1958 (not Pfeiffer,
1862), Bull. Mus. Nat. d'Hist. Nat., Paris, n. s., 30, (4), pp. 365-
366 — Makatea, Tuamotu Islands.
Diagnosis. — Shell relatively large, diameter 4.28-4.47 mm.,
(mean 4.40 mm.), with 7'/4-7% rather tightly coiled whorls. Apex
flat, spire moderately elevated, last whorl not descending, H/D ratio
0.554-0.615 (mean 0.583). Umbilicus narrow, U-shaped, slightly wider
apically than at last whorl, contained 6.50-7.30 times (mean 6.87) in
the diameter. Postnuclear sculpture of very weak, quite widely
spaced, protractively sinuated radial ribs, that are much more
prominent below periphery of body whorl than above and are
scarcely larger than the microradials. Microsculpture of fine radial
riblets, nine to twelve between each pair of major ribs, crossed by
much finer and very crowded spiral riblets, with a secondary
sculpture of very fine spiral cords most clearly visible on shell base.
Sutures not impressed, whorls flatly rounded above obtusely
angulated periphery, with evenly rounded lower palatal and basal
margins, sloping to sharply rounded umbilical margin. Aperture
ovate, periphery obtusely angulated, inclined about 20° from shell
axis. Parietal barriers 4, extending posteriorly three-sixteenths of a
whorl: upper high and bladelike, weakly expanded above on posterior
third, with very gradual anterior descension; 2nd and 3rd
equally high and expanded on posterior quarter, anterior half to five-
eighths low and threadlike; 4th parietal with posterior elevated
portion distinctly reduced in height, but not in length, anterior
portion threadlike. Columellar barrier a low lamellar ridge, almost
parallel to plane of coiling, stopping anteriorly near apex of
columellar callus, usually with one or two indistinct superior traces
above. Palatal barriers 5, extending posteriorly more than one-eighth
whorl, with one superior accessory trace: lower palatal slightly
reduced in height, high and crescentic, with sharp anterior
descension, only slightly recessed; 2nd, 3rd and 4th palatals distinctly
higher, slightly more expanded above posteriorly, with progressively
more gradual anterior descension and slightly deeper recession within
def
FIG. 95. a-c, Kleokyphus callimus, new species. Makatea, Tuamotu Islands. Paratype. Museum National d'Histoire Naturelle, Paris: d-f,
Kleokyphus hypsus, new species. Makatea, Tuamotu Islands. Holotvpe. Museum National d'Histoire Naturelle, Paris. Scale lines equal 1 mm.
(MM)'.
225
226
SOLEM: ENDODONTOID LAND SNAILS
aperture; 5th palatal reduced in height, a prominent V-shaped ridge
situated opposite 1st parietal, more deeply recessed within aperture.
Accessory trace low and threadlike, deeply recessed, located just
below parietal-upper palatal margin.
The presence of 4 parietals and 5 palatals at once
distinguish Kleokyphus callimus from the much larger
(diameter 6.60 mm.) K. hypsus, which has only 3
parietals and 4 palatals. While the supraperipheral
postnuclear sculpture of K. callimus is very similar to
that of Libera dubiosa, the greatly different umbilicus
and apertural barriers at o.ice separate the two species.
The sculpture also serves to immediately separate all
species of Mautodontha.
Description. — Shell rather large, with 7'4 rather tightly coiled
whorls. Apex flat, spire moderately elevated, last whorl not
descending more rapidly, H/D ratio 0.554. Embryonic whorls and
early postnuclear whorls with sculpture mostly eroded. Remaining
whorls with very low and inconspicuous, widely spaced, strongly
protractively sinuated radial ribs, too indistinct to count. Micro-
sculpture of very fine radial riblets, nine to twelve between each pair
of major ribs, crossed by much finer and more crowded spiral riblets,
with a secondary sculpture of weak spiral cording most clearly visible
on shell base. Sutures very shallow, whorls flatly rounded above
obtusely angulated periphery, evenly rounded on lower margin to
sharply rounded umbilical margin. Color light yellowish-white with
regularly spaced, relatively narrow, zigzag reddish flammulations
that fade out on shell base. Umbilicus narrow, U-shaped, slightly
wider apically than on last whorl, contained 6.50 times in the
diameter. Aperture subovate, periphery obtusely angulated, inclined
about 20° from shell axis. Parietal barriers 4, extending three-
sixteenths of a whorl: upper parietal weakly expanded and serrated
above for posterior third, with gradual anterior descension, 2nd and
3rd parietals with posterior third to quarter elevated and expanded
as in 1st, anterior half low and threadlike; 4th parietal with elevated
posterior portion reduced in height, with more gradual descension to
anterior threadlike portion. Columellar barrier a low lamellar ridge,
sharply descending anteriorly across peak of columellar callus, with
two indistinct broadly rounded traces present above. Palatal barriers
5, extending over one-eighth whorl, with one superior accessory
trace; lower palatal high, crescentic, bladelike, with relatively sharp
anterior descension almost to apertural edge: 2nd, 3rd and 4th
palatals slightly higher, progressively with more gradual anterior
descension, slightly more expanded and serrated above posteriorly, a
little more deeply recessed within aperture; 5th palatal slightly
subperipheral in position, greatly reduced in height, a V-shaped ridge
lying almost directly opposite 1st parietal. Accessory trace low and
threadlike, deeply recessed, located just below parietal-palatal
margin. Height of holotype 2.17 mm., diameter 4.28 mm.
Holotype. — Tuamotu Islands: Makatea. Collected
by E. Aubert de la Rue in 1955.
Range. — Makatea, Tuamotu Islands.
Paratypes. — Same as list of material.
Material. — Makatea (4 specimens, Paris, FMNH
153781).
Remarks. — Although the holotype is the smallest
of the three adult specimens, its state of preservation
is comparatively good. In the juvenile paratype the
apical sculpture can be seen to have the typical
endodontid pattern of fine radials interspersed with
one or two finer radial riblets and crossed by very fine
spiral riblets. All of the apical sculpture is slightly
reduced in prominence. The early postnuclear whorls
show relatively prominent radial ribbing, but by the
third whorl this has become reduced to the point that
it can scarcely be distinguished from the micro-radial
ribbing. The great reduction of the supraperipheral
sculpture, coupled with retention of relatively promi-
nent radial ribs on the shell base is unique among the
Polynesian Endodontidae and immediately separates
this species. The effect of the supraperipheral sculp-
ture is most similar to that found in Libera dubiosa
from Moorea, Society Islands, but the totally different
umbilical formation and apertural barriers prevent any
confusion of the two species.
The form of the apertural barriers is most similar
to those seen in Mautodontha boraborensis and M.
zimmermani from the Society Islands, but the great
number of whorls, elevated spire, very narrow um-
bilicus, and the reduced ribbing clearly separate
Kleokyphus callimus from Mautodontha. No other
genera are apt to be confused.
The specific name callimus, taken from the Greek,
meaning most beautiful, is in recognition of the
exquisite sculpture and bright color patterns of this
species.
Kleokyphus hypsus, new species. Figure 95d-f.
Libera gregaria Aubert de la Riie & Soyer, 1958 (not Garrett,
1884), Bull. Mus. Nat. d'Hist. Nat., Paris., n. s., 30, (4), pp. 365-
366 — Makatea, Tuamotu Islands.
Diagnosis and description. — Shell very large, diameter 6.60
mm., with 8 tightly coiled whorls. Apex and spire strongly elevated,
slightly rounded above, last whorl descending much more rapidly,
H/D ratio 0.683. Umbilicus narrowly U-shaped, last whorl decoiling
very slightly more rapidly, contained 5.61 times in the diameter.
Postnuclear sculpture of prominent, rather crowded, strongly
protractively sinuated radial ribs. Sutures deep, whorls strongly
rounded above evenly rounded outer margin. Aperture ovate, slightly
compressed laterally. Parietal barriers 3, extending slightly less than
three-sixteenths of a whorl, with at least three accessory traces
visible: upper parietal high and bladelike, with gradual descension
over anterior half; 2nd and 3rd parietals equally high for posterior
third, more strongly expanded above, with anterior third low and
threadlike. Accessory traces as follows: one between 2nd and 3rd
parietal; two between 3rd parietal and columellar-parietal margin.
No trace of a columellar barrier. Palatal barriers 4, extending about
one-eighth whorl: 1st palatal an elevated bladelike lamella with
rather sharp anterior descension; 2nd and 3rd slightly higher,
expanded posteriorly, with much more gradual anterior descension;
4th palatal a much lower, V-shaped ridge, lying opposite upper
parietal, extending slightly further anteriorly.
Kleokyphus hypsus obviously differs from the
smaller K. callimus in its larger size, much higher
spire, and presence of only 3 parietals and 4 palatals.
Species of Mautodontha with comparable barrier
numbers all are much smaller in size, much more
depressed, and with much wider umbilici.
Holotype. — Tuamotu Islands: Makatea. Collected
by E. Aubert de la Riie in 1955. Museum National
d'Histoire Naturelle, Paris. Height of holotype 4.51
mm., diameter 6.60 mm.
Range. — Makatea, Tuamotu Islands.
Material. — Makatea (1 specimen, Paris).
SYSTEMATIC REVIEW
227
Remarks. — Despite the extremely worn condition
of the single specimen, its large size, number and
length of the barriers, high whorl count, compressed
margin, and narrow umbilicus characterize it as a
second species of Kleokyphus. Its general appearance is
closest to some species belonging to the subgenus
Garrettoconcha, but unquestionably it is not
congeneric. The latter are much smaller, with fewer
whorls, lower spires, have much greater descension of
the body whorl and their umbilici tend to be much
wider and differently shaped.
Genus Opanara, new genus
Medium-sized Endodontidae with typical apical and major
radial sculpture. Microsculpture typical, only fosbergi with secon-
dary sculpture. Apex and spire varying from depressed (depasoapi-
cata) or flat (fosbergi, megomphala and areaensis areaensis), to
very strongly elevated (caliculata and altiapica), last whorl slightly
to moderately descending. Whorls laterally compressed, evenly
rounded, or compressed above and below a rounded periphery. A
supraperipheral sulcus present only in duplicidentata. Whorls 5% -
6-, less only in the modified altiapica and caliculata. Umbilicus
generally U-shaped, slightly to regularly decoiling, rarely extremely
widely open (megomphala) or almost closed (perahuensis), some-
times with angled or margined (caliculata and altiapica) border.
Parietal barriers normally 3, typical in form: either 2 or 3 in
bitridentata; 4 in duplicidentata; and altered to low threads with
accessory traces in megomphala. Columellar barrier small to large,
parallel or slightly angled in most species; displaced onto basal lip in
fosbergi by lateral compression; deflected onto basal lip in
areaensis; and reduced to many threadlike traces in megomphala.
Palatal barriers normally 4; increased to 5 in duplicidentata; broken
into many fine threads in megomphala; accessory traces present only
in bitridentata and duplicidentata. Ovotestis and hermaphroditic
duct (so far as known) typical, talon relatively short with rapidly
tapering shaft. Penial retractor arising from diaphragm (except
columellar muscle in duplicidentata), inserting onto fleshy extension
of penis head (no extension in depasoapicata and caliculata). Vas
deferens entering penis quite near head, just below union of pilasters.
Penial pilasters much higher than wide at base, simple and equal in
most forms; simple and unequal in depasoapicata, areaensis,
altiapica and caliculata; complexly folded in duplicidentata; and
separated in perahuensis. Spermathecal shaft entering free oviduct
just at peni-oviducal angle, so no vaginal region differentiated.
Radula typical, tooth size reduced in bitridentata and fosbergi. Jaw
of weak overlapping plates, broadly to narrowly rectangular.
Type species. — Opanara areaensis areaensis, new
species and subspecies.
The diverse appearing species grouped here share a
pattern of anatomical structure and seem to be the
base group from which the other Rapan genera have
been derived. The range of variation within Opanara
approximates that seen in other stem groups such as
Mautodontha and Minidonta and is much greater
than in any of the derived taxa. Opanara shows
numerous types of specialization, so that a neat,
simple generic definition is impossible.
Of extralimital genera, Opanara shows most
similarities to Mautodontha and the Marquesan taxa,
Taipidon and Planudonta. Mautodontha has a lower
mean whorl count, 4% - 5%, except in highly
specialized species; has a basic number of 4 parietal
barriers (often secondarily reduced); many more ribs;
differently shaped umbilici and whorl contours (except
some Garrettoconcha); and, on the basis of fragmen-
tary data, anatomical differences. The two partially
dissected Mautodontha lack a fleshy extension to the
penis head, have much more subapical insertion of the
vas deferens, the penis tapers much more abruptly and
the pilasters are low and rounded. Opanara has a
higher mean whorl count, 5%-6-, except in two
specialized species; has a basic number of 3 parietals
(rarely reduced); fewer ribs; less rapidly decoiling
umbilici with somewhat flattened sides (except
megomphala); usually a fleshy extension to the penis
head; little or no tapering to the penis; the pilasters
very high; and only slightly subapical insertion of the
vas deferens. The shell of Opanara is less specialized
than many Mautodontha, but its anatomy is more
advanced. Differences from Taipidon are discussed
below (p. 315).
Although the range of variation within Opanara
seems rather large, most of the changes should be
viewed as drastic alterations in single character
complexes that have major effects on the general
appearance of the species. The very depressed shape of
O. fosbergi (fig. 107c) is the result of compression from
above and below, while the high spire and H/D ratios
of O. caliculata and O. altiapica come from the
greatly increased tightness of coiling (fig. 98). Un-
doubtedly, the high spire and relatively high H/D
ratio of O. perahuensis derive from the umbilical
contraction.
Size range is not large (table LXXV), with only O.
duplicidentata (mean diameter 4.32 mm.) and O.
altiapica (mean diameter 2.82 mm.) departing
noticeably from a 3.11-3.77 mm. range. The variation
in spire height is reflected in the greater H/D ratios of
O. caliculata, O. altiapica, O. perahuensis, O.
areaensis microtorma, and O. a. densa, while the
extreme compression in O. fosbergi, depressed spire in
O. depasoapicata, and extreme umbilical widening in
O. megomphala have produced correspondingly low
H/D ratios. Whorl count is reduced in O. altiapica
and O. caliculata and disproportionately increased
only in O. megomphala (required for umbilical
widening) and O. depasoapicata (result of secondary
size reduction?). Umbilical width and form ranges
from the cup-shape of O. megomphala to the secondar-
ily narrowed O. caliculata and O. altiapica, and the
barely perforate O. perahuensis.
Rib counts are in the 60-85 range, except for O.
caliculata, 0. fosbergi, and O. areaensis densa, which
have rib counts of over 100 and, together with the
dwarfed O. altiapica, are the only species with really
crowded ribbing. None of the species have very widely
spaced ribbing (table LXXVII).
The apertural barrier pattern is conservative. Only
in O. bitridentata is there a frequent reduction to 2
parietals; occasionally there is a 4th parietal in O.
fosbergi and O. areaensis; and only in O. dupli-
cidentata is there normally a 4th parietal. The
Fit;. 96. Anatomy of Opanara: a-b, O. depasoapicata. Station 451, Mt. Perahu, Rapa. BPBM 142820. a, terminal genitalia, b, interior
of penis; c-f, O. bitridentatn. c-d, Station 512. Mt. Perahu, Rapa. BPBM 135484; c, genitalia. d, interior of penis; e-f, Station 451, Mt.
Perahu, Rapa, BPBM 142826. p, terminal genitalia, /, interior of penis; g-i, O. duplicidentata. Station 451, Mt. Perahu, Rapa. BPBM
142817. g, genitalia, h, interior of penis, i, detail of ovotestis clump; j-k, O. areaensis areaennia. Station 485, Mt. Mangaoa, Rapa. BPBM
138334. j, genitalia, k, interior of penis. Scale lines refer to a, c, e, g, and/ (See Appendix for explanation of abbreviations.)
228
u
FIG. 97. Anatomy of Opanara: a-b, O. altiapica. Station 526, Mt. Mangaoa, Rapa. BPBM 143742. a, genitalia, 6, interior of penis; c-
d, O. megomphala megomphala. Station 477, Mt. Tepiahu, Rapa. BPBM 144718. c, exterior of penis, d, interior of penis; e-f, O.
megomphala tepiahuensis. Station 459, Mt. Tepiahu, Rapa. BPBM 143004. e, genitalia, /, interior of penis; g, O. fosbergi. Terminal
genitalia. Station 450, Mt. Perahu, Rapa. BPBM 142808; h-i, O. perahuensis. Station 453, Mt. Perahu, Rapa. BPBM 142909. h, terminal
genitalia, i, interior of penis. Scale lines refer to figures a, c, e, g, and h. (See Appendix for explanation of abbreviations.)
229
230
SOLEM: ENDODONTOID LAND SNAILS
columellar barrier is simple in most species, deflected
onto the basal lip in O. areaensis and displaced in O.
fosbergi. Its size, recession, and degree of slant is
variable. O. megomphala has both the columellar and
palatal barriers reduced to threadlike, elongated
traces. Both O. duplicidentata and O. bitridentata
regularly have accessory traces on the palatal wall,
but only O. duplicidentata has 5 palatals (in O.
fosbergi the "5th" palatal is the displaced columellar).
Anatomically, the short, relatively stubby talon
contrasts greatly with the situation in Orangia, but is
very similar to the structure found in Ruatara.
Variability within Opanara in regard to penial
structures is much greater than the differences from
Orangia. Rhysoconcha is separated from Opanara by
its penial insertion of the spermatheca, while Ruatara
has a coiled hermaphroditic duct and only a single
pilaster inside the penis.
Penial variation in Opanara concerns several
features. In the very large O. duplicidentata the penial
retractor arises from the columellar muscle; in all
other species it is attached to the diaphragm. A fleshy
extension to the penis head is found in all species
except O. caliculata and O. depasoapicata. The
pilaster pattern is quite variable, becoming complexly
folded in O. duplicidentata; simple and grossly
unequal in size in O. depasoapicata, O. areaensis, O.
altiapica, and O. caliculata; the pilasters not joined
above and occupying overlapping longitudinal zones in
O. perahuensis (fig. 97i); and the pilasters of approxi-
mately equal size in the other species. All the pilasters
are of the narrow, greatly elevated type found in
Orangia, rather than the low, rounded pattern seen in
more generalized Endodontidae.
The jaws show simple variation. In the very small
O. depasoapicata, the plates are four or five times as
long as wide. In O. bitridentata the plates are
proportionately wider, but in O. duplicidentata size
increase has been accompanied by increase in number
of plates, with the length-width ratio as in O.
depasoapicata. In O. megomphala and O. perahuensis
the plates are very wide.
Form and shape of the radular teeth agree with
Orangia and Ruatara. Centrals are large in O.
areaensis, long and narrow in O. fosbergi (correlated
with the narrowed aperture?), and reduced in size only
in O. bitridentata. Laterals retain the same relative
size and shape as the centrals.
Within Opanara, no species can be selected as
strictly generalized, each form showing several special-
izations. O. areaensis, despite the flattened spire in the
nominate race and the deflection of the columellar
barrier onto the basal lip, shows comparatively few
specializations and thus has been chosen as genotype.
2£3
2.37
6
- 210
184
1.58
depasoapicata
caliculata
altiapica
duplicidentata
bitridentata
O
O
D
*A*
OV
** *
* *
£*
**
>
**
****
* *
n
D
D
D
DD
D
D
D
D
2.83
3.09
335
3.62 388
Diameter in mm.
4.14
4.41
4.67
433
FIG. 98. Relationship of height to diameter in Opanara altiapica, O. bitridentata, O. caliculata, O. depasoapicata, and O.
duplicidentata.
SYSTEMATIC REVIEW
231
O. depasoapicata, O. bitridentata, and O. dupli-
cidentata share a common pattern of growth (fig. 98),
but show a number of differences. The smallest
species, O. depasoapicata, has a depressed apex, with
correspondingly wide umbilicus and small H/D ratio.
Occasionally it has accessory palatal traces. Its penis
lacks a fleshy extension to the head and the pilasters
inside the penis are unequal in size. O. bitridentata is
somewhat larger, has a distinctly elevated spire, with a
correspondingly narrower umbilicus and greater H/D
ratio, either 2 or 3 parietal barriers, occasionally
additional palatal barriers and three to eleven ac-
cessory palatal traces. The genitalia conforms to the
normal Opanara pattern, with large, equal-sized
pilasters inside the penis. O. duplicidentata is by far
the largest species in the genus. It has a slightly
elevated spire, rather large umbilicus with angled
margins, a basic number of 4 parietals and 5 palatals
(the most in Opanara), plus six accessory palatal
traces. The penial retractor originates from the
columellar muscle, and the penial pilasters are very
large and complexly folded, more so than in any other
Opanara. The relative high whorl count of the small
O. depasoapicata (57/s-), absence of any fleshy exten-
sion to the penis head and grossly unequal pilaster size
are suggestive of size reduction and may be indicative
of a trend similar to that which culminated in
Rhysoconcha (see pp. 255-256). At the other extreme,
the elaboration of penial pilasters and transfer of the
penial retractor muscle origin in O. duplicidentata
often are characteristics of large size throughout the
Endodontidae and may have no special significance.
All three species are confined to Mt. Perahu.
As mentioned above, O. areaensis is specialized
primarily in the deflection of the columellar barrier
onto the basal lip. The pattern of this deflection is
unique. Anatomically it is a generalized form. Several
races are developed, the nominate form distinguished
by a flat spire, widely spaced ribbing and a normal
umbilicus; densa by its elevated spire, very crowded
ribbing and slightly smaller size; microtorma by its
elevated spire and narrower umbilicus. The nominate
race is rather widely distributed (fig. 101), the others
restricted to small areas. Probably areaensis evolved
from the base stock by rapid change and is less
specialized than the depasoapicata-duplicidentata
series.
Opposite trends in variation are shown by O.
megomphala, then by the closely related O. caliculata
and O. altiapica. O. megomphala has the umbilical
opening enormously enlarged, the columellar and
palatal barriers reduced to threadlike traces, and the
parietal barriers reduced in size with several accessory
traces developed. Isolated populations on Mt. Tepiahu
and Mt. Tautautu (fig. 100) differ in proportions,
ribbing, and rib spacing. No anatomical differences
were noted and subspecific recognition has been given
to the two populations. O. caliculata and O. altiapica
present an almost opposite set of specializations.
O fosbergi
perahuensis
depasoapicata
if bitridentata
duplicidentata
FIG. 99. Distribution of Opanara in the Mt. Perahu region.
Narrowing and deepening of the umbilicus has been
accompanied by drastic spire elevation. The umbilical
margin is distinctly angled and the umbilicus itself
slightly secondarily narrowed in both species. There is
no alteration in the barriers from the generalized
pattern. While the conchological differences between
O. altiapica and O. caliculata are no larger than those
between the races of O. megomphala, specific level
separation of the former is required because dissection
demonstrated anatomical differences (see p. 17).
The remaining two species, O. fosbergi and O.
perahuensis present, respectively, simple and complex
departures from the generalized pattern. O. fosbergi
(fig. 107c-d) should be viewed as a species specialized
only in being strongly compressed above and below.
The evident transfer of the columellar barrier to the
palatal wall, the very low H/D ratio, and narrow
umbilicus all relate to this one simple fact. Otherwise
it is a quite generalized species. O. perahuensis shows a
number of unique features. The umbilicus is essen-
tially closed by contraction, the ribbing very widely
spaced with large microradials, and the penis has the
two pilasters not joined above, but occupying over-
lapping zones in the penis. The apertural barriers are
simple. O. perahuensis seems somewhat intermediate
between Ruatara and Opanara, although anatom-
232
SOLEM: ENDODONTOID LAND SNAILS
ically belonging to the latter insofar as its anatomy is
known.
Until the apical genitalia of O. perahuensis can be
examined and Ruatara koarana dissected, the exact
relationship of Opanara and Ruatara will remain
uncertain. The latter is a derivative group and the
structure of Opanara perahuensis indicates in um-
bilical contour and pilaster pattern how the structures
of Ruatara could have developed from the Opanara
pattern. The essential differences are: closure of the
umbilicus by contraction, partial reduction, then
fusion of the penial pilaster remnants, and coiling of
the hermaphroditic duct. The barrier reduction in
Ruatara oparica probably is a secondary phenomenon.
Orangia is less altered anatomically, but shows
many conchological changes. The penis has unequal
pilasters, which are very high apically (fig. 121k) and
the fleshy penis head, lack of a vagina, and uncoiled
hermaphroditic duct are typical. Orangia differs in its
very long talon. Conchologically, the presence of only
2 parietals, closure of the umbilicus by reflection,
angulated periphery, development of secondary micro-
sculpture, and generally much larger size easily
separate Orangia from Opanara. Kondoconcha also is
derivable from Opanara, but differs in many features
from Orangia, although similar in size and barriers.
The many features separating Rhysoconcha and
Opanara are discussed under the former genus.
Distributional patterns of Opanara are simple. A
majority of the species are restricted to the slopes of
Mt. Perahu (figs. 99, 100): O. caliculata, O. fosbergi, O.
Rapa Island
Rapa Island
(_) m. megomphala
9 m tepiahuensis
/\ caliculata
^ altiapica
FIG. 100. Distribution of Opanara megomphala, O. caliculata,
and O. altiapica.
FIG. 101. Distribution of Opanara areaensis.
perahuensis, O. depasoapicata, O. duplicidentata, and
O. bitridentata. O. altiapica is a derivative of O.
caliculata found in another part of the island (fig.
100), O. megomphala has two subspecies (fig. 100) on
separate mountains, and only O. areaensis (fig. 101)
has a relatively broad distribution. Compared with the
patterns shown by Orangia, Ruatara, and Rhyso-
concha, this is quite restricted and suggests that
Opanara is in the process of being replaced by the
derivative genera.
KEY TO THK GKNUS Opanara
Umbilicus moderately to widely open, contained less than 9
times in the diameter 2
Umbilicus closed or narrowly perforate, contained more than 12
times in the diameter Opanara perahuensis, new species
Palatal barriers reduced to many fine traces 3
Palatal barriers 4-6, large 4
Mean H/D ratio less than 0.450; Mt. Tepiahu.
Opanara megomphala tepiahuensis, new subspecies
Mean H/D ratio more than 0.500; Mt. Tautautu.
Opanara megomphala megomphala, new subspecies
Columellar barrier present, simple 5
Columellar barrier absent or deflected onto basal lip 9
Accessory palatal barriers absent 6
Accessory palatal barriers present 8
Apex and spire moderately to strongly elevated; D/U ratio
more than 3.50 7
Apex and spire sunken; D/U ratio less than 3.25.
Opanara depasoapicata, new species
Less than 100 ribs on body whorl; mean H/D ratio more than
0.700 Opanara altiapica, new species
More than 110 ribs on body whorl; mean H/D ratio less than
0.650 Opanara caliculata, new species
SYSTEMATIC REVIEW
233
8. Parietal barriers 2 or 3; umbilicus narrower, mean D/U ratio
more than 5.00 Opanara bitridentata, new species
Parietal barriers 4; umbilicus wider, mean D/U ratio about 3.00.
Opanara duplicidentata, new species
9. Columellar barrier deflected onto basal lip (fig. 104e); H/D
ratio more than 0.500 10
Columellar barrier absent, H/D ratio less than 0.400.
Opanara fosbergi, new species
10. Apex and spire distinctly elevated 11
Apex and early spire flat.
Opanara areaensis areaensis, new subspecies
11. Less than 90 ribs on body whorl; mean ribs/mm, about 7.00.
Opanara areaensis microtorma, new subspecies
More than 90 ribs on body whorl; mean ribs/mm, about 9.75.
Opanara areaensis densa, new subspecies
Opanara depasoapicata, new species. Figures
96a-b; 107e-f.
Diagnosis. — Shell rather small, diameter 3.05-3.15 mm. (mean
3.11 mm.) with 5%-6 tightly coiled whorls. Apex and early spire
sunken below level of antipenultimate whorl, last two whorls
descending slightly, H/D ratio 0.489-0.505 (mean 0.494). Umbilicus
broadly open, U-shaped, last whorl slightly decoiling, contained 2.88-
2.97 times (mean 2.92) in the diameter. Postnuclear sculpture of
narrow, prominent, normally spaced, slightly protractively sinuated
radial ribs, 78-84 (mean 81.0) on the body whorl, whose interstices
are 3-4 times their width. Microsculpture of very fine radial riblets,
five to eight between each pair of major ribs, crossed by extremely
fine and crowded spiral riblets. Sutures impressed, whorls strongly
rounded above and on umbilical margin, evenly rounded on outer
margin, umbilical walls very slightly flattened. Aperture ovate,
evenly rounded on outer margin, inclined slightly more than 5° from
shell axis. Parietal barriers 3, extending posteriorly about three-
sixteenths of a whorl: upper high and bladelike, expanded and
serrated above on posterior quarter, with very gradual anterior
descension until just before end; 2nd parietal with posterior elevated
portion slightly lower and shorter, middle two-thirds an elevated
bladelike ridge, with gradual anterior descension, extending well
beyond end of upper parietal; 3rd parietal greatly reduced in height
posteriorly, scarcely elevated, a broad and threadlike ridge equal in
length to 2nd parietal. Columellar wall with a single broad, very
deeply recessed threadlike ridge, barely visible without tilting of
aperture. Palatal barriers 4, sometimes 5 or 6, short, extending less
than one-eighth whorl: 1st palatal a high crescentic lamella with
abrupt anterior descension, only slightly recessed within aperture;
2nd palatal slightly reduced in height, a little more flattened above,
with more gradual anterior descension and deeper recession; 3rd
palatal greatly reduced in height, a low lamellar ridge, weakly
expanded above, with very gradual anterior descension, located
below level of upper parietal; 4th palatal supraperipheral, lying
above level of upper parietal, a short deeply recessed threadlike
ridge, very slightly elevated posteriorly.
The absence of any palatal traces, very small size,
depressed apex, and presence of only 3 parietal barriers
immediately distinguish Opanara depasoapicata from
O. duplicidentata. The latter is much larger, has 4
parietals, several palatal traces, and a much larger,
more prominent columellar barrier. O. bitridentata has
a much narrower umbilicus, elevated spire, and either
2 or 3 parietals. O. areaensis is immediately separable
in having the columellar barrier large and sharply
deflected onto the basal lip.
Description. — Shell very small, with 5?/s tightly coiled whorls.
Apex and early spire sunken below level of antipenultimate whorl,
last two whorls descending slightly, H/D ratio 0.505. Apical whorls
l'/2, sculpture of fine radial riblets interspersed with finer micrp-
radials and crossed by microspiral riblets. Postnuclear whorls with
narrow, prominent, almost vertically sinuated radial ribs, 84 on the
body whorl, whose interstices are 2-3 times their width. Micro-
sculpture of fine radial riblets, four to eight between each pair of
major ribs, crossed by much finer and more crowded spiral riblets.
Sutures impressed, whorls strongly rounded above and on umbilical
margin, slightly compressed laterally with evenly rounded outer
margin, inner walls of umbilicus somewhat flattened. Color light
yellow-brown, with vague traces of widely scattered, reddish
flammulations. Umbilicus broadly U-shaped, last whorls decoiling
slightly, contained 2.97 times in the diameter. Aperture ovate,
slightly compressed laterally, with angulated umbilical margin, and
flattened columellar wall, inclined less than 5° from shell axis.
Parietal barriers 3, extending posteriorly about three-sixteenths of a
whorl: upper parietal high and bladelike, expanded and serrated
above on posterior quarter, middle two-thirds with very gradual
descension, becoming sharp near anterior end; 2nd parietal elevated
above posteriorly, with more gradual anterior descension, anterior
portion reduced in height, extending further anteriorly than upper
parietals; 3rd parietal a raised threadlike ridge for entire length,
extending equally far anteriorly as 2nd parietal. Columellar barrier a
low lamellar ridge, deeply recessed in aperture, clearly visible only by
tilting shell. Palatal barriers 4, short, extending about one-eighth
whorl; lower palatal basal in position, a high crescentic lamella with
abrupt anterior descension. almost reaching lip edge, expanded and
serrated above; 2nd palatal slightly reduced in height, a little
flattened above, with equally abrupt anterior descension; 3rd palatal
greatly reduced in height, expanded and serrated above posteriorly, a
raised lamellar ridge, with very gradual anterior descension; 4th
palatal reduced to a high threadlike trace, shortened, moderately
recessed within aperture, with very gradual anterior descension.
Height of holotype 1.58 mm., diameter 3.12 mm.
Holotype. — Austral Islands: Rapa Island, Station
451, east ridge of Mt. Perahu at 1,200-1,500 ft.
elevation. Collected by Yoshio Kondo on July 21, 1934.
BPBM 142820.
Range. - East ridge of Mt. Perahu at 1,200-1,800
ft. elevation, Rapa Island, Austral Islands.
Paratypes. — Same as list of material.
Material. - Rapa: east ridge of Mt. Perahu
(Stations 451, 452, 509) at 1,200-1,800 ft. elevation (15
specimens, BPBM 135441, BPBM 142819-22, ex BPBM
142823, BPBM 142824, BPBM 142876, ex BPBM
142873).
Remarks. — Two specimens had additional palatal
barriers: BPBM 142824 had extra palatals between the
1st and 2nd, then 2nd and 3rd; one of three specimens
in BPBM 142819 had a 5th palatal located between
the 1st and 2nd. In both cases the extra barriers were
equal in size and shape to the normal palatals. There
was no variation noted in the parietal barrier pattern.
The depressed apex and very wide umbilicus found
in O. depasoapicata immediately separate it from
other species found on Rapa. While O. megomphala
has an even wider umbilicus, it has the apertural
barriers reduced to threadlike traces. O. dupli-
cidentata is much, much larger, has 4 parietals and 5
palatals, and much more widely spaced radial ribbing.
Opanara depasoapicata was a relatively rare
species, taken in lesser number than O. duplicidentata
at Stations 451 and 452, then in almost equal,
although sparse, numbers at Station 509.
FIG. 102. a-d, Opanara bitridentata, new species, a-b, narrowly umbilicated form with 2 parietals. Station 512, Mt. Perahu, Rapa Island,
Austral Islands. Paratype. BPBM 135483, form with 3 parietals; c, Station 512, Mt. Perahu, Rapa Island, Austral Islands. Holotype. BPBM
135484; d. widely umbilicated example. Station 451, Mt. Perahu, Rapa Island, Austral Islands. Paratype. BPBM 142826; e-f, O. duplicidentata,
new species. Station 451, Mt. Perahu, Rapa Island, Austral Islands. Holotype. BPBM 142817. Scale lines equal 1 mm. Drawings by YK
reproduced through the courtesy of Bernice P. Bishop Museum.
234
SYSTEMATIC REVIEW
235
Unfortunately, only fragmentary soft parts were
available. The penis is unusual for Opanara in lacking
a fleshy head, a character shared only with O.
caliculata. All other dissected forms have a fleshy
head to the penis. Internally, the penial pilasters are
very simple and lack the rather complex folding seen
in such species as O. duplicidentata. Other features of
the soft parts could not be studied.
Description of soft parts. — Penial retractor inserting directly on
head of penis, no fleshy extension. Vas deferens (fig. 96a VD)
entering penis to one side of pilaster, about 0.33 mm. below penis
apex. Penis (P) about 2.35 mm. long, swollen on upper half,
internally (fig. 96b) with two very high pilasters (PP), one much
longer and larger than the other, united above. Attached edge of
pilasters narrower than medial section, pilaster much, much higher
than wide. Spermathecal shaft (S) joining free oviduct (UV) just
above penioviducal angle.
Jaw composed of clearly separate plates, moderately over-
lapping, each plate four or five times as long as wide.
Radula with about 5 laterals, central 10 n wide and 11 long,
marginals missing or folded under.
(Based on fragmentary and torn individuals from BPBM
142820.)
Opanara bitridentata, new species. Figures 96c-f;
102a-d.
Diagnosis. — Shell of slightly less than average size, diameter
2.79-3.88 mm. (mean 3.26 mm.), with 5% normally coiled whorls.
Apex and spire slightly and evenly elevated, last whorl descending a
trifle more rapidly, H/D ratio 0.483-0.580 (mean 0.524). Umbilicus
broadly (fig. 102d) to narrowly (fig. 102b) open, U-shaped, last
whorls slightly to moderately decoiling, contained 3.58-8.45 times
(mean 5.31) in the diameter. Postnuclear whorls with narrow,
prominent, slightly protractively sinuated lamellar radial ribs, 70-91
(mean 79.1) on the body whorl, whose interstices are 3-5 times their
width. Microsculpture of fine radial riblets, five to eight between
each pair of major ribs, crossed by extremely fine and crowded spiral
riblets barely visible under 96 x magnification. Sutures impressed,
whorls strongly and almost evenly rounded on outer margins, with
more strongly rounded subsutural and umbilical margins. Aperture
subcircular, with strongly rounded outer margins, inclined about 10°
from shell axis. Parietal barriers 2 (61.8 per cent) or 3 (38.2 per cent),
extending posteriorly slightly more than three-sixteenths of a whorl,
rarely (1 of 81 specimens) with a small accessory trace near parietal-
columellar margin: upper parietal high and bladelike, expanded and
serrated above on posterior half, with gradual anterior descension
until just before anterior end; 2nd parietal more strongly
expanded and serrated above on posterior half, equally elevated,
with rather sharp anterior descension to a threadlike trace or
threadlike ridge occupying anterior three-eighths of barrier and
terminating beyond end of upper parietal; 3rd parietal, when present,
located between 1st and 2nd, deeply recessed, equally high and
serrated posteriorly, but without anterior threadlike portion, termi-
nating somewhat past mid-point of 1st parietal. Columellar wall with
a single, low, moderately recessed threadlike trace to lamellar ridge,
slanting slightly downward from plane of coiling. Palatal barriers
normally 4, often 5 (15.1 per cent) or occasionally 6 (6.1 per cent),
extending posteriorly over one-eighth whorl: 1st palatal basal in
position, a low lamellar blade, flat above, expanded and serrated
above on posterior three-quarters, moderately recessed, with relative-
ly sharp anterior descension; 2nd palatal normally indistinctly
higher, expanded and serrated above on posterior half, with more
gradual anterior descension; 3rd palatal equal in height to 2nd or
slightly reduced, similarly expanded and serrated above, a little more
deeply recessed, with slightly more gradual anterior descension; 4th
palatal supraperipheral in position, greatly reduced in height, more
deeply recessed, a low threadlike trace lying above level of upper
parietal. Additional palatals, when present, located between various
pairs of lower palatals. Accessory traces three to eleven in number,
most frequently present above upper palatal, when more numerous
with one or two between each pair of lower palatals.
The pronounced variation in diameter, number of
parietal barriers, and umbilical width found in Opa-
nara bitridentata makes confusion with other species
relatively easy. Opanara depasoapicata differs in its
always much wider umbilicus and slightly depressed
(not elevated) spire. O. duplicidentata is generally
much larger, almost always has a much wider
umbilicus, always has 4 parietals, 5 palatals, and six
palatal traces. O. areaensis microtorma has a much
thicker body whorl, greatly enlarged and deflected
columellar barrier, and much larger parietal and
palatal barriers.
Description. - Shell of average size, with 5'/4 normally coiled
whorls. Apex and spire slightly and evenly elevated, last whorl
descending a little more rapidly, H/D ratio 0.525. Apical whorls 1%,
sculpture typical. Postnuclear whorls with narrow, lamellar, rather
crowded, protractively sinuated radial ribs, 76 on the body whorl,
whose interstices are 2-4 times their width. Microsculpture of fine
radial riblets, four to six between each pair of major ribs, crossed by
exceedingly fine and crowded spiral riblets that are barely visible
under 96 X magnification. Sutures deep, whorls strongly rounded
above and on umbilical margin, with strongly and evenly rounded
outer margins. Color light yellow-horn, with prominent, strongly
zigzagged, reddish flammulations that tend to coalesce and broaden
near umbilicus. Umbilicus U-shaped, relatively wide, last whorls only
slightly decoiling contained 4.31 times in the diameter, internal wall
strongly rounded below, somewhat flattened apically. Aperture
subcircular, with strongly rounded outer margins, inclined about 10°
from shell axis. Parietal barriers 3, 2nd deeply recessed, extending
posteriorly more than three-sixteenths of a whorl: upper high and
bladelike, expanded and serrated above on posterior third, with
extremely gradual anterior descension until just before its termina-
tions; 2nd parietal equally high and expanded above posteriorly,
much shorter than elevated portion of 1st parietal, descending
sharply to a very slender threadlike trace that terminates before
anterior quarter of upper parietal; 3rd parietal with posterior
elevated portion as in 2nd, slightly longer, with a little more gradual
anterior descension to raised threadlike ridge that extends anteriorly
slightly beyond termination of 1st parietal. Columellar barrier a
broad, low, lamellar ridge, slanting slightly downward from plane of
coiling and stopping short of lip margin. Major palatal barriers 4,
with numerous accessory traces both above upper palatal and
between lower pairs: lower palatal high and bladelike, expanded,
serrated, and slightly flattened above, with rather gradual anterior
descension; 2nd palatal slightly higher, longer, with posterior
elevated portion proportionately shorter and with more gradual
anterior descension, a little more deeply recessed within aperture; 3rd
palatal as in 2nd, with more gradual anterior descension and slightly
deeper recession; 4th palatal slightly supraperipheral, greatly reduced
in height, a raised threadlike ridge lying above plane of upper
parietal. Palatal traces very fine and numerous. Height of holotype
1.71 mm., diameter 3.26 mm.
Holotype. — Austral Islands: Rapa Island, Station
512, east end of main ridge of Mt. Perahu at 1,500-
1,850 ft. elevation. Collected under moss and between
leaves of bird's nest ferns by Donald Anderson and
natives on July 28, 1934. BPBM 135484.
Range. - East ridge of Mt. Perahu at 1,500-1,900
ft. elevation, Rapa Island, Austral Islands.
Paratypes. — Same as list of material.
Material. — Rapa: east ridge of Mt. Perahu at
1,200-1,900 ft. elevation (Stations 446, 450, 451, 453,
TABLE LXXVI. - LOCAL VARIATION IN OPANARA, RUATARA KOARANA AND KONDOCONCHA OTHNIUS
Name
Number of
Specimens Height
Diameter
H/D Ratio
Whorb
D/U Ratio
Opanara
altlapica
BPBM 143741-3, -6,
BPBM 143335
Sta. 481, 526
caliculata
8 2.02±0.069 2.83*0.053
(1.76-2.32) (2.65-3.05)
0.714±0.0120 51/4- 4.59*0.134
(0.664-0.761) (47/8-55/8) (3.91-5.12)
BPBM 142908, EX. 3
BPBM 135484
Sta. 453, 512
2. 02±0.119
(1.85-2.25)
3.27±0.086
(3.11-3.41)
0.617±0.0214
(0.595-0.660)
5-
(4 5/8-5 1/4)
4.74±0.335
(4.09-5.22)
bltrldentata
1.60*0.044
(1.39-1.82)
3.08*0.055
(2.81-3.38)
0.519±0.0069
(0.483-0.580)
5 1/4-
(5-5 3/4)
5.49±0.250
(4.31-6.93)
BPBM 135483-5 13
Sta. 512
BPBM 142799, -801 7
Sta. 450
1.77±0.048
(1.59-1.92)
3.33±0.085
(3.01-3.58)
0.533*0.0049
(0.519-0.550)
5 1/2-
(5 1/8-5 5/8)
4.61±0.178
(3.84-5.26)
BPBM 142826 4
Sta. 451
1.90±0.044
(1.79-1.99)
3.60±0.034
(3.51-3.68)
0.529*0.0085
(0.510-0.551)
5 5/8+
(5 5/8-5 3/4)
4.29*0.510
(3.58-5.79)
perahuensls
BPBM 142909 4
Sta. 453
1.88±0.008
(1.85-1.89)
3.20±0.086
(3.05-3.34)
0.590±0.0175
(0.555-0.620)
5 1/2+
(5 1/2-5 5/8)
22.2±2. 35
(15.3-25.3)
fosbergl
BPBM 135444, 5
BPBM 142808
Sta. 450. 509
1.30±0.032
(1.19-1.39)
3.77±0.066
(3.61 4.01)
0.344±0.0081
(0.330-0.375)
5 1/2
(5 3/8-5 5/8)
7.10±0.389
(5.74-8.07)
depasoaplcata
BPBM 142820, 4
BPBM 142876
Sta. 451-2
1.54±0.022
(1.49-1.59)
3.11±0.024
(3.05-3.15)
0.494±0.0038
(0.489-0.505)
5 7/8-
(5 5/8-6)
2.92*0.025
(2.88-2.97)
megomphala megomphala
BPBM 144717-8 5
Sta. 477
megomphala tepiahuensls
BPBM 143003-5, -7 24
Sta. 459
1.63±0.087
(1.39-1.89)
1.46±0.025
(1.16-1.66)
3.15±0.093
(2.85-3.34)
3.36±0.035
(2.98-3.77)
0.516*0.0134
(0.488-0.564)
0.434±0.0061
(0.353-0.481)
5 3/4-
(5 1/4-6 1/8)
5 7/8
(5 1/2-6 1/8)
2.22±0.036
(2.15-2.35)
1.95*0.016
(1.72-2.08)
duplicidentata
BPBM 142745 4
Sta. 446
2. 20±0.010
(2.19-2.22)
4.20*0.028
(4.14-4.27)
0.525i0.0020
(0.520-0.528)
5 7/8
2.59±0.070
(2.49-2.80)
BPBM 142872 6
Sta. 452
2. 38±0.093
(2.15-2.78)
4.32±0.119
(4.14-4.87)
0.552±0.0102
(0.520-0.575)
6-
(5 5/8-6 1/4)
3.04±0.090
(2.78-3.32)
BPBM 142817-8 15
Sta. 541
2.40±0.059
(2.02-2.72)
4.34±0.090
(3.74-4.87)
0.553±0.0065
(0.508-0.594)
6
(5 3/8-6 7/8)
3.17±0.075
(2.63-3.65)
Ruataia
1.69±0.077
(1.56-1.82)
2.95±0.119
(2.81-3.05)
0.612±0.0306
(0.567-0.670)
5 1/8-
(4 3/4-5 1/2)
BARELY OPEN
TO CLOSED
koaiana
BPBM 142521 3
Sta. 357
Kondoconcha
2.30±0.064
(2.09-2.55)
4.06±0.067
(3.81-4.24)
0.567±0.0086
(0.548-0.601)
6 3/8-
(6 1/8-6 3/4)
5.55*0.225
(5.00-6.40)
othnlus
BPBM 142462, -3, -7 6
Sta. 346
236
SYSTEMATIC REVIEW
237
TABLE LXXVII. - RIBS /MM. IN OPANARA
m. rnegorn phala
rn. tepiahuensis
fosbergi
perahuensis
8.38(7.
7.94(6.
5.99(5.
5.68(4.
6.86(6.
9.75(8.
8.93(7.
11.76 -
7.09(6.
6.39(5.
8.57(8.
6.18(5.
93-8.82)
65-0.09)
13-7.17)
18-7.47)
47-7.30)
63-11.03)
38-10.35)
69-7.31)
34-7. 54)
04-8.96)
78-6.72)
512, 513) under stones, moss and debris (81 specimens,
BPBM 135483-7, ex BPBM 135488, BPBM 135573,
BPBM 142747, BPBM 142799-807, BPBM 142826,
BPBM 142906-7).
Remarks. — Considerable variation exists within
this species (table LXXVI) and some of it seems to be
clinally oriented. While H/D ratios and rib counts are
essentially identical, other parameters vary widely.
Specimens taken at 1,200-1,500 ft. elevation (Stations
446 and 451) are distinctly larger and with a wider
umbilicus than specimens taken at 1,500-1,900 ft.
elevation (Stations 450, 453, 512, and 513). Comparing
material from Station 512 and Station 451, with 15 df,
"t" = 5.0527 in respect to diameter and "t" = 2.2684
for D/U ratio. Comparing specimens from Station 450
with Station 451, there is less difference in D/U ratio,
since with 9 df, "t" = 2.3303 for diameter and "t" =
0.7263 for D/U ratio. The percentage changes involved
between Stations 450 and 451 in height, diameter, and
D/U ratios are, respectively, 7.3 per cent, 8.1 per cent,
TABLE LXXVIII. - PARIETAL BARRIER VARIATION
IN OPANARA BITRIDENTATA
Station
512
513
UU6
1*51
TOTAL
2 Pr
2
0
10
2
2
5
21
3 Pr
7
3
3
0
0
0
13
and 7.5 per cent. Between Stations 512 and 450, the
percentage changes in height and diameter are 10.6 per
cent and 8.1 per cent, respectively, but there is a 19.1
per cent change in D/U ratio. This probably indicates
the relatively greater decoiling of the last umbilical
whorl in larger individuals. Stations 450, 512, and 451
are at progressively greater elevations and there is an
obvious decrease in height and diameter with a
narrowing of the umbilicus. Limited data suggests that
this is accompanied by changes in rib spacing. Thirteen
examples from Stations 450 and 512 averaged 78.5 ribs,
with 8.12 ribs/mm, (range 7.30-9.09), while three
specimens from Stations 446 and 451 averaged 82.0
ribs, with 7.17 ribs/mm, (range 6.65-7.87). Probably
this is another example of the phenomenon noted in
Opanara areaensis, where increase in mean diameter
produced an increase in rib spacing (see table LXXX).
Barrier variation primarily concerns the number
of parietals. Only part of the material was checked for
total counts, 34 of the 81 specimens, and the results
are tabulated in Table LXXVIII. The results are quite
discordant, with stations showing reverse dominance
despite the overall approach toward a two-to-one ratio.
The number of accessory palatal traces was quite
variable and an occasional specimen had one or two
extra palatals.
The name bitridentata refers to the variable
nature of the parietal barriers.
Dissection of specimens from Stations 451 (BPBM
142826) and 512 (BPBM 135484) showed no differ-
ences, with the penial pilasters equal and disparate in
size within the same sample. The pilasters are very
high and slender, tapering rapidly submedially. The
insertion of the vas deferens is clearly subapical.
One preserved specimen had a single egg in the
umbilicus. The umbilical diameter was 0.58 mm. and
the maximum egg diameter 0.55 mm. Removal of the
egg capsule showed a fully formed shell covering with
clearly defined sculpture.
Description of soft parts. — Foot and tail shorter than shell
diameter, narrow, not tapered, bluntly rounded behind. Sole
undivided. Pedal grooves prominent, rather high on foot, no caudal
horn or micldorsal groove. Slime network very faint. Head extending
in front of the truncated foot. Ommatophores typical. Gonopore
behind right rhinophore, above front margin of foot.
Body color light yellow-white, without darker markings.
Mantle collar with thickened edges, particularly around
pneumostome, no glandular extension onto pallial roof.
Pallial region extending five-eighths whorl apically. Lung roof
clear, white granules clustered just above apex of kidney. Kidney
almost 1.5 mm. long, rectal arm equal to half length, very slender
anteriorly. Ureter typical, originating subapically, reflexing sharply
for about one-quarter of length to open at anterior end of rectal
kidney arm next to hindgut. Heart about 0.6 mm. long, parallel to
hindgut, less than half length of kidney. Principal pulmonary vein
narrow, fading out short of mantle collar. Hindgut typical.
Ovotestis (fig. 96c, Gl with six to seven clumps of palmately
clavate alveoli, normally oriented to shell axis, individual clumps less
split than in O. duplicidentata. Hermaphroditic duct (GD) very
slender at first, moderately to strongly expanded medially, sharply
238
SOLEM: ENDODONTOID LAND SNAILS
reflexed just before entering carrefour. Albumen gland (GG) slender,
more elongated than in many species. Talon evenly tapering from
head to carrefour. head not grossly expanded. Carrefour enlarged
more laterally than in O. duphcidentata, clearly distinguishable from
talon in all views.
Prostate (DG) with two or three rows of acini opening into
slender tube. Uterus (UT) bipartite, lower chamber greatly ex-
panded, slightly larger than prostate.
Vas deferens (VD) typical, entering penis about 0.33 mm. below
penial apex and to one side of pilaster U. Penial retractor (PR)
originating from diaphragm just at apex of pallial cavity, inserting
on fleshy head of penis. Penis (P) about 2.65 mm. long, with very
prominent fleshy head, moderately swollen below insertion of vas
deferens, then narrowing and maintaining even diameter up to atrial
junction. Internally (fig. 96d, f), penis with two pilasters, united
above, sometimes equal in size, sometimes with one much higher and
larger, not united anteriorly. Pilaster shape typical. Atrium (Y) short
and rather broad.
Free oviduct (UV) larger than prostate, point of origin from
uterus clearly marked by a constriction. Spermatheca (S) with
elongately oval head, one specimen with a large, hooked, sperm
packet with only a weak membranous covering. Shaft inserting on
free oviduct just above penioviducal angle.
Free muscle system and digestive system typical.
Jaw of large overlapping plates, individual plates about three or
four times as long as wide.
Radula with elongated basal plates that are longer than wide,
rather short cusps, central about 6 n wide and 8 n long. Marginals
partly missing in all mounts.
(Based on BPBM 135484, three individuals and several frag-
mentary ones, whole shell 2.82 mm. in diameter with 4V&- whorls.)
Opanara duplicidentata, new species.
96g-i; 102e-f; 103.
Figures
Diagnosis. — Shell very large, diameter 3.72-4.84 mm. (mean 4.32
mm.), with 5% - 6'4 tightly coiled whorls. Apex and early spire flat or
slightly depressed below level of antipenultimate whorl, last two
whorls descending slightly, H/D ratio 0.508-0.594 (mean 0.549).
Umbilicus broadly open, U-shaped, last whorls barely dec-oiling,
contained 2.49-3.65 times (mean 3.03) in the diameter. Postnuclear
sculpture of prominent, crowded, almost vertically sinuated radial
ribs, 70-100 (mean 84.2) on the body whorl, whose interstices are
distinctly less than twice their width. Microsculpture of fine radial
riblets, three to five between each pair of major ribs, crossed by
extremely fine and crowded .spiral riblets. Sutures impressed, whorls
strongly rounded above, v^ry slightly compressed laterally above and
below evenly rounded periphery, baso-columellar margin strongly
angulated, inner walls of columellar region flattened. A weak
supraperipheral sulcus usually present. Aperture ovate, very slightly
flattened laterally above and below periphery, lying parallel to shell
axis. Parietal barriers 4, extending posteriorly slightly more than
one-quarter whorl, 2nd usually greatly reduced in prominence, often
(25 per cent) with a single short, deeply recessed accessory trace
below 4th parietal: upper parietal high and bladelike, expanded and
serrated above on posterior half, with very gradual anterior
descension; 2nd parietal normally only half height of the 1st, with
much shorter elevated portion that descends sharply to a threadlike
trace terminating well behind anterior end of 1st parietal, sometimes
much larger or smaller than the normal condition; 3rd parietal with
posterior half almost equal in height to 1st parietal, expanded and
serrated above, with moderate descension to a raised lamellar ridge
that occupies anterior half of barrier, terminating well before end of
1st parietal; 4th parietal with same shape as 3rd, usually slightly
reduced in height. Parietal trace, when present, a short, threadlike
structure recessed almost to mid-point of 4th parietal and
stopping well short of posterior end. Columellar barrier a high blade-
like ridge, expanded and serrated above posteriorly, with gradual
anterior descension and twisting slightly downwards, recessed within
aperture. Palatal barriers 5, extending posteriorly about three-
sixteenths of a whorl, with six deeply recessed accessory traces: lower
palatal greatly reduced in height, a weakly elevated lamellar ridge
with very gradual anterior descension; 2nd palatal high, expanded,
serrated and flattened above, with sinuated gradual anterior
descension; 3rd and 4th palatals slightly higher than 2nd, similar in
form, with more elongated anterior descension; 5th palatal located
well above periphery, greatly reduced in height, a low lamellar ridge
situated above level of upper parietal. One palatal trace located
between each pair of major palatals, with two additional traces
between upper palatal and palatal-parietal margin.
The presence of 4 parietals, many accessory
palatal traces, flattened sides of the umbilicus, and
very large size immediately separate Opanara dupli-
cidentata from the other Rapan species. The other
large species, the several Orangia and Kondoconcha,
either have a closed umbilicus (Orangia) or an
angulated periphery (Kondoconcha) and all have only
2 parietals.
Description. — Shell large, with 6'/4 very tightly coiled whorls.
Apex and spire flat, lower whorls descending slightly more rapidly,
H/D ratio 0.547. Apical whorls I'/s, sculpture of fine radial riblets
interspersed with one or two finer microradials and crossed by rather
widely spaced spiral microriblets. Postnuclear whorls with low,
rather broad, closely spaced, almost vertically sinuated radial ribs, 85
on the body whorl, whose interstices are 1-2 times their width.
Microsculpture of fine radial riblets, three to five between each pair
of major ribs, crossed by very fine and crowded spiral riblets. Sutures
impressed, whorls strongly rounded above down to very weak
supraperipheral sulcus, the outer margin evenly rounded, slightly
compressed laterally below periphery, with strongly angulated baso-
columellar margin and flattened umbilical wall. Color light yellow-
brown, with faint traces of irregular, reddish flammulations.
Umbilicus broadly open, U-shaped, last whorls barely decoiling,
contained 3.39 times in the diameter, inner walls flattened. Aperture
ovate, with almost evenly rounded outer margin, baso-columellar
FIG. 103. Details of carrefour region in Opanara duplicidentata:
a, top view with albumen gland follicles completely removed; b,
bottom view showing enlargement of carrefour. Greatly enlarged and
diagrammatic. See Appendix for explanation of abbreviations.
SYSTEMATIC REVIEW
239
margin sharply angulated, lying parallel to plane of shell axis.
Parietal barriers 4, extending posteriorly more than one-quarter
whorl, 2nd reduced in size: upper parietal high and bladelike,
expanded and serrated above on posterior five-eighths, with very
gradual anterior descension; 2nd parietal greatly reduced in height,
anterior threadlike and moderately recessed, with posterior elevated
portion distinctly shorter and lower than 1st parietal; 3rd parietal
equal in height to 1st, posterior half expanded and serrated above
with rather sharp descension to anterior elevated ridgelike lamellar
portion that terminates far in front of anterior end of 1st parietal;
4th parietal almost identical in size and shape to 3rd. Columellar
barrier a raised lamellar ridge, expanded and serrated above
posteriorly, with gradual anterior descension, slanting slightly
downward across columellar wall, stopping well short of lip margin.
Palatal barriers 5, extending posteriorly almost three-sixteenths of a
whorl, with six short, low accessory traces: lower palatal greatly
reduced in height, a weakly elevated lamellar ridge with gradual
anterior descension; 2nd palatal high and bladelike, flattened and
expanded above posteriorly with sinuated anterior descension; 3rd
and 4th palatals distinctly higher than 2nd, with more gradually
sinuated anterior descension; 5th palatal located above level of upper
parietal, greatly reduced in height, scarcely larger than some of the
larger accessory traces, deeply recessed within aperture. Palatal
traces located as follows: one between each pair of major palatals
(omitted in type figure between first and second palatals) and two
above 5th palatal (omitted in type figure). Height of holotype 2.50
mm., diameter 4.57 mm.
Holotype. — Austral Islands: Rapa Island, Station
451, east ridge of Mt. Perahu at 1,200-1,500 ft.
elevation. Collected by Yoshio Kondo on July 21, 1934.
BPBM 142817.
Range. - East ridge of Mt. Perahu at 1,200-1,900
ft. elevation, Rapa Island, Austral Islands.
Paratypes. — Same as list of material.
Material. — Rapa Island: east ridge of Mt. Perahu
(Stations 446, 450, 451, 452, 509, 511, 512, 513) at 1,200-
1,900 ft. elevation (39 specimens, BPBM 135419,
BPBM 135440, BPBM 135490, BPBM 135575, BPBM
142745, BPBM 142798, BPBM 142817, BPBM 142828,
BPBM 142872-4).
Remarks. — Opanara duplicidentata is the only
species of this genus that normally has 4 parietals.
Occasionally a specimen of O. fosbergi will have a 4th
parietal, but all other species normally have only 3
parietals. Rib variation was rather large, but not
between stations.
At Stations 444, 451, and 452 O. duplicidentata
was the most frequently collected species. Only at
Station 451 were the numbers large enough (18
Opanara duplicidentata, 10 O. depasoapicata, and 16
Orangia cookei montana) to be meaningful. Some
collecting bias may have been introduced by the
distinctly larger size of O. duplicidentata, but since
Kondo was the only collector at the station, I am
inclined to accept its greater abundance.
Dissection of several individuals showed a few
peculiarities of structure. The buccal retractor was not
split and the penial retractor arose from the colu-
mellar muscle, not the diaphragm. Internally, the
penis has the pilasters higher and much more
complexly folded than in most other Opanara. The
columellar muscle origin of the penial retractor is
sometimes found in forms with increased size (see pp.
81-83) and has no particular systematic significance.
The penial length of 1.5-2.0 mm. is quite short in
comparison with other Opanara.
Description of soft parts. — Foot and tail retracted into shell in
all specimens, tail not tapering, rounded behind. Sole undivided.
Pedal grooves high on side of foot, prominent. Slime network very
faint.
Body color yellow-white, without darker markings.
Mantle collar thin, edges expanded only around pneumostome,
no glandular extension onto pallia! roof. Pneumostome typical, no
mantle lobes.
Pallial region extending slightly less than three-quarters whorl
apically. Lung roof with scattered white granules, mainly clustered
around hindgut, pulmonary vein, and edges of kidney and ureter.
Kidney about 2.15 mm. long, rather broad anteriorly, rectal arm
about half of length. Ureter arising subapically, reflexed and opening
at anterior end of rectal kidney arm. Heart slightly less than half
length of kidney, lying parallel to hindgut. Principal pulmonary vein
and hindgut typical.
Ovotestis (fig. 96g, G) of six to eight clumps of palmately clavate
alveoli extending for about one-half whorl above stomach, positioned
as in Endodonta fricki (fig. 163c).
Hermaphroditic duct (GD) tapering apically, medially of
uniform diameter, abruptly narrowed to a thin tube, then reflexing
apicad before entering carrefour. Albumen gland (GG) longer and
more slender than in most species, extending further beyond apex of
talon than shown in Figure 96g. Talon (GT) with bulbous head and
short tapered shaft, entering directly into carrefour, which shows
asymetric lateral entrances of albumen gland duct and hermaphro-
ditic duct (fig. 96g). Prostate (DG) with one or two rows of acini
opening into a narrow tube, partly hidden by uterine area. Uterus
(UT) bipartite, lower area greatly swollen, narrowing abruptly just
beyond end of prostate to enter free oviduct.
Vas deferens (VD) typical, lightly bound to penioviducal angle,
entering penis subapically just inside margin of apical pilaster
junction, about one-quarter of length from top of penis. Penial
retractor (PR) arising from columellar muscle just below point where
buccal retractors join columellar muscle at apex, inserting directly
onto fleshy extension of penis head. Penis (P) about 1.5 mm. long,
expanded on upper third, with long fleshy extension to penis head.
Internally (fig. 96h), with two complexly expanded and folded
pilasters (PP) tha' are narrow, low, and fused apically, greatly
modified medially, and narrowed, then fused near atrium. Central
portion of pilasters very high and thicker above than on base.
Atrium (Y) short, rather narrow.
Free oviduct (UV) clearly differentiated from uterus, longer
than prostate. Spermatheca (S) with narrow elongated head in
typical position, inserting on oviducal side of penioviducal angle.
Free muscle system typical, except buccal retractor not split in
examined specimens. Digestive system without unusual features.
Jaw of large, overlapping plates, individual plates about 4-5
times as wide as long. No clear indication of fusion between plates.
Radula with cusps about equal in length to basal plate, central
about 10 ft wide, 11 fi long. Generally, 5 laterals and more than 9
marginals, all specimens fragmented during mounting.
(Based on BPBM 142817, two whole and several partial
specimens. One whole specimen 4.18 mm. in diameter, with
whorls.)
Opanara areaensis, new species.
Specimens were found in greatest numbers on the
lower slopes of Mt. Tanga at 250-450 ft. elevation,
northwest of Mt. Tavaitahu at 600-750 ft. elevation,
240
Name
areaensis areaensis
BPBM 142555
Sta. 366
BPBM 140502
Sta. 383
BPBM 140503
Sta. 383
BPBM 144301
Sta. 382
BPBM 142468
Sta. 346
BPBM 144145. -6
Sta. 340
BPBM 138334
Sta. 485
BPBM 143293, -4, 8
Sta. 478
BPBM 137949,
BPBM 144022,
BPBM 144040
Sta. 316, 317
areaensis densa
SOLEM: ENDODONTOID LAND SNAILS
TABLE LXXIX. - LOCAL VARIATION IN OPANARA AREAENSIS
Number of
Specimens
15
57
10
8
32
8
Height
Diameter
H/D Ratio
Whorls
D/U Ratio
1.7V±0.035
(1.56-2.02)
3.29±0.045
(3.05-3.64)
0.535±0.0054
(0.506-0.581)
5 1/4+
(5-5 5/8)
3.41±0.070
(3.07-4.04)
1.77±0.013
(1.55-1.94)
3.28±0.016
(2.96-3.52)
0.538±0.0025
(0.500-0.584)
5 1/4-
(4 3/4-5 5/8)
3.44±0.027
(2.99-4.00)
2.01+.0.027
(1.85-2.09)
3.62±0.031
(3.44-3.74)
0.555±0.0060
(0.518-0.573)
5 5/8
(5 1/2-5 7/8)
3.61*0.110
(3.27-4.23)
1.82±0.020
(1.72-1.92)
3.40±0.026
(3.25-3.51)
0.536*0.0035
(0.520-0.550)
5 3/8-
(5 1/4-5 5/8)
3.36±0.076
(3.12-3.93)
1.77±0.041
(1.59-1.95)
3.42±0.080
(3.05-3.77)
0.519±0.0028
(0.505-0.530)
5 1/2+
(5 1/4-6)
3.46±0.088
(2.97-3.83)
2.01+.0.025
(1.82-2.35)
3.64±0.027
(3.44-3.97)
0.551*0.0044
(0.510-0.634)
5 5/8 +
(5 1/4-6 1/4)
3.81±0.041
(3.28-4.19)
2.02*0.037
(1.89-2.25)
3.58±0.071
(3.25-3.91)
0.564±0.0050
(0.540-0.582)
5 5/8-
(5 3/8-6)
3.78±0.085
(3.50-4.16)
2.09±0.044
(1.97-2.30)
3.72±0.068
(3.45-3.98)
0.561±0.0065
(0.534-0.578)
5 7/8-
(5 5/8-6)
3.83±0.081
(3.50-4.17)
1.98±0.035
(1.88-2.11)
3.55±0.070
(3.36-3.82)
0.557i0.0120
(0.534-0.615)
5 5/8-
(5 3/8-5 7/8)
4.42*0.099
(4.14-4.73)
BPBM 144711, -4
Sta. 477
areaensis mlcrotorma
BPBM 135437,
BPBM 142746,
BPBM 142875,
ex BPBM 142818
Sta. 446, 451-2, 509
1.90±0.056
(1.69-2.19)
2.10±0.036
(1.99-2.19)
3.30±0.062
(3.15-3.68)
3.60±0.017
(3.54-3.64)
0.574±0.0092 5 3/8+
(0.537-0.616) (51/8-53/4)
0.584±0.0103
(0.551-0.607)
5 3/4-
(5 1/2-6)
3.60±0.099
(3.31-3.97)
4.11±0.069
(3.86-4.27)
and on Mt. Mangaoa at 800 ft. elevation. Scattered
examples were found in the Maitua region at 500-750
ft. elevation and on Mt. Perahu at 1,200-1,800 ft.
elevation.
This was the first species complex studied.
Measurements were made using material as segregated
into age groups by the Bishop Museum staff in the
mid-1930's. The measured material included both
adult and paraneanic specimens. During study of this
material, I became aware that there was a clear set of
previously unrecognized criteria by which adult shells
could be separated from subadult specimens (see pp.
11-13). Time did not permit restudy of the O.
areaensis material to eliminate paraneanic specimens
from the measurements. Hence the variation shown
between sets (table LXXIX) is misleading. The
specimens from Station 340 (BPBM 144145-6), Station
383 (BPBM 140503), and Station 485 (BPBM 138334)
contain only adult and gerontic individuals selected
from large samples, while measured material from
Stations 366, 382, 346, and 474 contained mixtures of
adults and paraneanic specimens from smaller total
samples and averaged much less in size. Another set
from Station 383 (BPBM 140502) contained many
paraneanic specimens and no gerontic individuals,
hence it averaged much smaller and slightly lower
than the specimens from BPBM 140503.
Size variation, although appearing rather great,
was not large once the distortion introduced by
inclusion of paraneanic individuals is discounted.
There were noticeable differences in shape and umbili-
cal width. While most individuals had a flat apex and
spire (fig. 104a), specimens from Stations 477 and 478
northwest of Mt. Tautautu, Station 527 on Mt.
Mangaoa, and the specimens from Mt. Perahu have
the spire almost evenly elevated as in Figure 104c.
There was no major change in H/D ratio accom-
panying the spire elevation, since those forms with
elevated apex and spire had the relative descension of
the body whorl reduced. Umbilical width showed a
normal distribution, except for the presence of nar-
rowly umbilicated forms on Mt. Perahu and from the
Maitua area (fig. 104f). The six measured Maitua
shells from Stations 316 and 317 had a mean D/U
ratio of 4.42, which was narrower than the Perahu
populations (mean D/U ratio 4.11) and much less than
the average for the nominate race (mean D/U ratio
3.62). There was no significant alteration in H/D ratio
(means of 0.557 for Maitua; 0.549 for nominate race;
0.584 for Perahu shells).
Ribbing variation (table LXXX) included the
presence of shells with very numerous (90-113) and
crowded (8.63-11.03 ribs/mm.) major radial ribs at
SYSTEMATIC REVIEW
TABLE LXXX. - RIB VARIATION IN OPANARA AREAENSIS
241
Name
areaensls areaensls
BPBM 140502
Sta. 383
BPBM 144649-50
Sta. 474
BPBM 142468
Sta. 346
BPBM 144145-7
Sta. 340
BPBM 143293-5
Sta. 478
All Measured Specimens
areaensls densa
BPBM 144711
Sta. 477
areaensis microtorma
All
Number of
Specimens
57
30
Diameter
10
3.28±0.
(2.
3.36±0.
(3.
3.44±0.
(3.
3.51±0.
(3.
3.63±0.
(3.
016
96-3.52)
028
06-3.62)
081
32-3.75)
094
16-3.98)
081
32-3.98)
Rib Count
58.2±0.70
(49-70)
61.7±0.98
(51-72)
57.0±1.92
(53-64)
56.0±2.27
(49-68)
58.2±2.16
(51-71)
Ribs/mm.
5.70±0.
(4.
5.84±0.
(4.
5.29±0.
(4.
5.07±0.
(4.
5.10±0.
(4.
043
89-6.71)
077
99-6.51)
255
67-6. 14)
092
65-5.46)
143
18-5.68)
3.53
60.2"
5.68'
(3.03-3.98)
3.35±0.086
(3.13-3.65)
3.57±0.017
(3.52-3.62)
(49-88)
102.6±4.58
(90-113)
77. Oil. 92
(73-83)
(4.18-7.47)
9.75±0.385
(8.63-11.03)
6.86±1.31
(6.47-7.30)
1. Based on 126
2. Based on 152
Stations 477 and 478 northwest of Mt. Tautautu;
moderately numerous (66-88) and crowded (5.41-7.47
ribs/mm.) radial ribs on the shells from Mt. Perahu,
Mt. Mangaoa (Stations 485 and 527), and Maitua
(Station 316); with specimens from the other localities
showing less numerous (49-71) and more widely spaced
(4.18-6.71 ribs/mm.) radial ribs.
The patterns of variation outlined above are less
clearly segregated and more diffuse than those in
Orangia cookei, Ruatara oparica, Opanara megom-
phala, or Rhysoconcha, but are essentially similar.
Specimens from Mt. Perahu have a distinctly
elevated apex and early spire, a narrower umbilicus
than most specimens, and rather crowded and numer-
ous radial ribs. They were taken at a much higher
altitude than other areaensis populations and are
recognized by the subspecific name microtorma.
Specimens from Station 477 and one of 14
specimens from Station 478 have very crowded radial
ribbing, an elevated apex, and quite different appear-
ance from the typical examples. They are recognized
by the subspecific name densa. Other specimens from
Station 478 are typical areaensis. A difference of only
50 ft. altitude separates the two stations. Collections
from the lower station (478) were made by Kondo,
from the upper (477) by Wight, Kondo, and Cooke. I
suspect that the two forms actually are separated
micro-geographically and the recording of one densa
from the Station 478 areaensis population is a simple
error in bottling field material.
The subspecies may be characterized as follows:
Opanara areaensis areaensis has a flat apex and
early spire, open (mean D/U ratio 3.67) umbilicus,
relatively few (mean 60.2) and widely spaced (mean
ribs/mm. 5.68) radial ribs.
Opanara areaensis densa has a raised apex and
early spire, open (mean D/U ratio 3.62) umbilicus,
very many (mean 103.5) and crowded (mean ribs/mm.
9.75) radial ribs.
Opanara areaensis microtorma has a raised apex
and early spire, narrow (mean D/U ratio 4.11)
umbilicus, with an intermediate number (mean 77.0) of
moderately spaced (mean ribs/mm. 6.86) radial ribs.
Opanara areaensis areaensis, new species and
subspecies. Figures 96j-k; 104a-b.
Diagnosis. — Shell relatively large, diameter 3.03-3.98 mm.
(mean 3.53 mm.), with 5Vfc - 6'4 rather tightly coiled whorls. Apex and
early spire flat or barely elevated, later whorls descending quite
rapidly in adults, H/D ratio 0.505-0.634 (mean 0.549). Umbilicus
242
SOLEM: ENDODONTOID LAND SNAILS
broadly open, U-shaped, last whorls barely or moderately decoiling,
contained 2.97-4.01 times (mean 3.67) in the diameter, with sharply
angulated margin and rather strongly flattened whorls internally.
Postnuclear sculpture of narrow, prominent, rather widely spaced,
slightly protractively sinuated radial ribs, 49-88 (mean 60.2) on the
body whorl, whose interstices are 4-6 times their width. Micro-
sculpture of fine radial riblets, six to ten between each pair of major
ribs, crossed by barely visible and crowded spiral riblets. Sutures
impressed, whorls very strongly rounded above and on umbilical
margin, compressed laterally with evenly rounded outer margin.
Aperture subovate, strongly rounded above on umbilical margin,
inclined about 10° from shell axis. Parietal barriers 3, occasionally
(6.3 per cent) with a small 4th parietal located between upper two,
extending posteriorly more than three-sixteenths of a whorl: upper
parietal high and bladelike, weakly expanded and serrated above on
posterior eighth, with practically no anterior descension until last
quarter of length; 2nd parietal slightly reduced in height posteriorly,
posterior elevated portion about one-fourth length of tooth, with
gradual anterior descension to a low threadlike ridge that extends
anteriorly beyond termination of upper parietal; 3rd parietal, high
and bladelike, expanded and serrated above on posterior third, with
relatively gradual anterior descension, never becoming threadlike
anteriorly; 4th parietal, when present, usually very short and greatly
reduced posteriorly with anterior threadlike portion of variable
length, normally situated between 1st and 2nd parietals, rarely (1.5
per cent) an accessory trace above upper or below 3rd parietal.
Columellar barrier high and bladelike, weakly expanded above,
posteriorly lying parallel to plane of coiling, anteriorly deflected
sharply downward onto basal lip, abruptly descending to lip margin,
broadly expanded at anterior end. Palatal barriers 4, rarely (3.1 per
cent) with 2nd or 3rd tooth bifid, extending posteriorly for about
one-eighth whorl: 1st palatal very high and bladelike, flattened,
weakly expanded, and serrated above with abrupt anterior descen-
sion to lip margin, often grossly expanded at anterior end; 2nd and
3rd palatals equal in height to 1st or slightly reduced, almost
reaching lip margin, with progressively more gradual anterior
descension; 4th palatal greatly reduced in height, a shorter, recessed
lamellar ridge, only weakly expanded above, supraperipheral, lying
well above plane of upper parietal.
The abrupt and complete deflection of the
columellar barrier onto the basal lip immediately
separates Opanara areaensis areaensis from the other
Rapan species. Only Ruatara koarana has the
columellar barrier similarly deflected, and that species
has the progressively more deeply recessed parietals
and a barely perforate or closed umbilicus. The widely
open, U-shaped umbilicus with angled margin imme-
diately differentiate O. areaensis from the Anceyo-
donta that have a deflected columellar barrier, plus
the deflection of the latter occurring in a different
fashion. Opanara areaensis densa differs in its
distinctly elevated spire (fig. 104c) and much more
crowded radial ribs (90-113 on the body whorl).
Opanara a. microtorma differs in its distinctly
narrower umbilicus (fig. 104f).
Description. — Shell of average size, with 5% normally coiled
whorls. Apex and early spire flat, last two whorls descending much
more rapidly, H/D ratio 0.528. Apical whorls 1%, sculpture of low,
widely spaced radial ribs, interspersed with one or two microriblets,
then crossed by very fine and rather widely spaced spiral riblets.
Postnuclear whorls with narrow, prominent, lamellar, protractively
sinuated radial ribs, 71 on the body whorl, whose interstices are 3-6
times their width. Sutures deep, whorls strongly rounded above and
on angulated umbilical margin, slightly compressed laterally with
evenly rounded outer margins. Color light yellow horn with vague
traces of irregular, zigzagged, reddish flammulations. Umbilicus
widely open, U-shaped, last whorl slightly decoiling, contained 3.67
times in the diameter, margin distinctly shouldered. Aperture ovate,
laterally compressed, inclined about 10° from shell axis. Parietal
barriers 3, extending posteriorly about three-sixteenths of a whorl,
with a single threadlike trace situated below 3rd parietal: upper
parietal high and bladelike, serrated and expanded above on
posterior quarter, with very gradual anterior descension until just
before end; 2nd parietal reduced in height, expanded and serrated
above on posterior third, with rather sharp anterior descension to
threadlike anterior half extending beyond termination of upper
parietal; 3rd parietal high and bladelike, expanded and serrated
above on posterior third, with very gradual anterior descension to an
elevated lamellar ridge that terminates opposite end of 2nd parietal.
A weak threadlike trace located below 3rd parietal. Columellar,
barrier a high lamellar ridge, weakly expanded above, posteriorly
lying parallel to plane of coiling, deflected sharply downward onto
basal lip with abrupt anterior descension, grossly expanded at
anterior end. Palatal barriers 4, extending posteriorly about one-
eighth whorl: lower palatal very high, bladelike, flattened, expanded
and serrated above, with abrupt anterior descension almost to lip
margin, weakly expanded at anterior tip; 2nd and 3rd palatals equal
in height to 1st, with more gradual anterior descension, almost
reaching lip margin; 4th palatal greatly reduced in height, a low
lamellar ridge, weakly expanded above, shorter and more deeply
recessed, lying above plane of upper parietal. Height of holotype 1.91
mm., diameter 3.62 mm.
Holotype. — Austral Islands: Rapa Island, Station
474, hillside back of Area at 400 ft. elevation. Collected
under stones by Donald Anderson on July 24, 1934.
BPBM 144649.
Range. — Scattered lowland to middle elevation
localities on both north and south Rapa Island,
Austral Islands.
Paratypes. — Same as list of material.
Material. — Rapa Island: hillside back of Area
(Stations 366, 382, 383, 474) at 250-450 ft. elevation
under stones (629 specimens, BPBM 140502-7, BPBM
142555-9, BPBM 144301-4, BPBM 144649-51); hillside
and valley west of Tavaitahu (Station 346) at 750 ft.
elevation under stones (11 specimens, BPBM 142468-
70); area near Maitua (Stations 316, 317, 319, 353, 358)
at 500-750 ft. elevation (13 specimens, BPBM 135698-9,
BPBM 137949, BPBM 138535, BPBM 140017, BPBM
144022, BPBM 144040); northeast ridge and its west
slope of Mt. Mangaoa (Stations 403, 485, 527) at 800 ft.
elevation (41 specimens, BPBM 138334-6, BPBM
138407, BPBM 144381); northwest of Tavaitahu
(Stations 340, 478) at 600-750 ft. elevation (96
specimens, BPBM 143293-8, BPBM 144145-50).
Remarks. — Tooth variation within this species
was surprisingly slight. One individual had the 3rd
parietal bifid, another had a 4th trace below the 3rd
parietal and eight had a 4th parietal located between
the 1st and 2nd. Three specimens had the 2nd palatal
bifid, one had the 3rd palatal bifid, and two specimens
had extra palatals.
Descension of the columellar barrier onto the
basal lip near the aperture is one of the most
distinctive features found in Opanara areaensis. While
this might be taken as an "adult" character, since
posteriorly the columellar barrier lies parallel to the
plane of coiling, even the youngest individuals have
a-f
FlG. 104. a-b, Opanara areaensis areaensis, new species and subspecies. Station 474, Area, Rapa Island, Austral Islands. Holotype.
BPBM 144649; c-d, O. a. densa, new subspecies. Station 477, Mt. Tautautu, Rapa Island, Austral Islands. Holotype. BPBM 144711; e-f,
O. a. microtorma, new subspecies. Station 509, Mt. Perahu, Rapa Island, Austral Islands. Holotype. BPBM 135437. Scale lines equal 1
mm. Figures a-d by YK reproduced through the courtesy of Bernice P. Bishop Museum; e-f (MM).
243
244
SOLEM: ENDODONTOID LAND SNAILS
the columellar displaced onto the basal lip. Continu-
ance of this growth pattern presents some problems,
since instead of the anterior addition and posterior
resorption normally required during whorl increment,
continuation of the basal deflection and posterior
parallelism demands anterior resorption and growth
plus similar changes at the posterior section of the
twisted portion. A study of the growth mechanism
would be very worthwhile.
Because delineation of this complex was rather
difficult, several sets were borrowed for further study.
Rib counts were made at a later time from both adult
and paraneanic individuals (as explained above, pp.
40-44). The availability of abundant material
allowed checking the effect of size increment on rib
frequency. Table LXXX presents data from five sets
ranked in increasing mean diameter. It is obvious that
there is a general trend for an increase in mean
diameter to be accompanied by a slight increase in rib
spacing. There is no such trend in regard to actual rib
count. This confirms data obtained from populations
of Anceyodonta obesa (pp. 203-204) where reduction in
adult shell size was not accompanied by reduction in
rib count, but only by an increase in rib crowding.
Comparing populations of O. areaensis from Stations
383 and 478 in respect to rib frequency, with 95 df, "t"
= 4.1969. I have no doubt that this shift in rib spacing
is real and important.
As noted above in the general discussion of O.
areaensis, the Maitua populations differ in their
umbilical width (see data on Stations 316-317 in table
LXXIX) and tendency toward an elevated spire. In
sculpture and form they are much more like O.
areaensis areaensis then either of the other sub-
species, although showing tendencies toward them.
The anatomy differs from that seen in other
Opanara only in the variability of relative penial
pilaster size and more nearly apical insertion of the vas
deferens.
Description of soft parts. — Foot and tail fully retracted in all
specimens examined.
Body color yellow-white, without darker markings.
Mantle collar with thickened edges, no glandular extension into
pallial cavity. Pneumostome typical, no mantle lobes developed.
Pallial region extending more than five-eighths whorl apically.
Lung roof clear, a few scattered specks near kidney surface. Kidney
about 1.6 mm. long, tapering anteriorly, rectal arm about one-third
length of pericardia!. Ureter typical, originating behind kidney
anterior end, reflexing basally, opening just anterior of rectal arm
termination. Heart about one-half length of kidney, not parallel to
hindgut. Principal pulmonary vein slender, fading out just short of
mantle collar. Hindgut at parietal-palatal margin for about one-
eighth whorl above pallial cavity termination.
Ovotestis (fig. 96j, G) occupying half whorl above stomach
reflexion, comprising four main clumps of palmately clavate alveoli.
Hermaphroditic duct (GD) slender at point of stomach reflexion,
rather narrowly expanded, tapering gradually to typical reflexion
before entering laterally on talon. Albumen gland (GG) very small in
younger specimens, typical in appearance. Talon (GT) with enlarged
head, narrow connecting shaft and enlarged lower portion buried in
albumen gland. Prostate (DG) of one or two rows of large acini
opening into a slender tube that continues into vas deferens, acinar
section rather short. Uterus (UT) composed of a narrower upper
portion (UTi), with a wider, thicker walled lower section (UT2).
Vas deferens (VD) very slender, entering penis head subapically,
but much nearer apex than in most Opanara. Penial retractor (PR)
originating from diaphragm just above apex of pallial cavity,
inserting on fleshy head of penis. Penis (P) about 2.65 mm. long,
tapering apically, internally (fig. 96k) with two pilasters, low and
broad basally, becoming very slender and high apically, then
tapering to a junction at constricted head of penis. Vas deferens
opening (DP) located between main part and weak arm of one
pilaster. Atrium (Y) very short.
Free oviduct (UV) tapering slightly from uterus to atrium,
highly twisted because of animal retraction. Spermatheca (S)
entering free oviduct just above atrium, shaft slightly expanded
basally. Vagina (V) not morphologically differentiated.
Free muscle system typical. Right ommatophoral retractor
passing through penioviducal angle.
Buccal retractors not split, uniting with pedal retractors just
before columellar muscle termination. Esophagus typical. Stomach
occupying almost one whorl, reflexing normally. Intestinal loops
occupying first eighth whorl above pallial cavity apex.
Jaw of many very narrow overlapping plates, each plate five or
six times as long as wide.
Radula with about 6 laterals and more than 7 marginals, central
about 11 n wide and 13 long with cusps as long as basal plates.
(Based on BPBM 138334, BPBM 142468, whole retracted
specimens 3.16 mm. with 5Vfc whorls, 4.01 mm. with 5%+ whorls.)
Opanara areaensis densa, new subspecies. Fig-
ure 104c-d.
Diagnosis. — Shell of average size, diameter 3.15-3.68 mm. (mean
3.32 mm.), with 5% - 534 normally coiled whorls. Apex and early spire
distinctly elevated, last whorl descending a little more rapidly, H/D
ratio 0.537-0.616 (mean 0.572). Umbilicus broadly open, U-shaped,
last whorl slightly decoiling, contained 3.31-3.97 times (mean 3.62) in
the diameter. Postnuclear sculpture of narrow, crowded, lamellar,
slightly protractively sinuated radial ribs, 90-113 (mean 103.5) on the
body whorl, whose interstices are 2-3 times their width. Micro-
sculpture of fine radial riblets, three to six between each pair of
major ribs, crossed by barely visible and extremely crowded spiral
riblets. Sutures deep, whorls strongly rounded above and slightly
compressed laterally, with evenly rounded outer margin, umbilical
margin shouldered, columellar wall flattened. Aperture ovate,
slightly compressed laterally, inclined about 5° from shell axis.
Parietal barriers 3, extending posteriorly more than three-sixteenths
of a whorl: upper parietal high and bladelike, strongly expanded and
serrated above on posterior third, with scarcely any anterior
descension until anterior eighth of barrier; 2nd parietal slightly
reduced in height, posterior third expanded and elevated above,
sharply descending to an anterior threadlike trace that normally
terminates beyond end of upper parietal, sometimes (11.1 per cent)
with threadlike portion extremely shortened; 3rd parietal high and
bladelike, expanded and serrated above on posterior third, with very
gradual anterior descension to an elevated threadlike lamellar ridge
that terminates opposite end of 2nd parietal. Columellar barrier a
high bladelike lamella, expanded and serrated above parallel to plane
of coiling posteriorly, twisted sharply downward onto basal lip with
abrupt anterior descension, weakly expanded at anterior tip. Palatal
barriers 4, extending posteriorly more than one-eighth whorl: lower
palatal high and bladelike, flattened, expanded and serrated above,
with abrupt anterior descension almost to lip margin, weakly
expanded at anterior tip; 2nd and 3rd palatals equal in height to 1st,
with more gradual anterior descension, slightly more deeply recessed;
4th palatal supraperipheral, reduced in height and length, an
elevated lamellar ridge situated above level of upper parietal.
SYSTEMATIC REVIEW
245
The distinctly elevated spire and crowded, numer-
ous radial ribs distinguish Opanara areaensis densa
from the nominate subspecies, which has the apex and
early spire flat and only 49-88 (mean 60.2) radial ribs
on the body whorl. O. areaensis microtorma differs in
its much less crowded and more widely spaced radial
ribs and narrower umbilicus (D/U ratio 3.86-4.27,
mean 4.11).
Description. — Shell of average size, with 5'/2 normally coiled
whorls. Apex and spire slightly and evenly elevated, last whorl
descending more rapidly, H/D ratio 0.616. Apical whorls 1%,
sculpture typical. Postnuclear whorls with narrow, prominent,
lamellar, almost vertically sinuated radial ribs, 113 on the body
whorl, whose interstices are two to three times their width.
Microsculpture of very fine radial riblets, three to five between each
pair of major ribs, crossed by barely visible and extremely crowded
spiral riblets. Sutures deep, whorls strongly rounded above, slightly
compressed laterally and with evenly rounded outer margin,
umbilical margin distinctly shouldered, columellar wall flattened.
Color light yellow-white, with prominent, strongly zigzagged, reddish
flammulations that tend to coalesce on shell base. Umbilicus broadly
open, U-shaped, last whorl moderately decoiling, contained 3.54
times in the diameter. Aperture ovate, compressed laterally, inclined
less than 5° from shell axis. Parietal barriers 3, extending posteriorly
more than three-sixteenths of a whorl: upper parietal high and
bladelike, expanded and serrated above on posterior quarter, with
exceedingly gradual anterior descension until just before termina-
tion; 2nd parietal almost equally high on posterior third, expanded
and serrated above, with rather sharp anterior descension to a short
threadlike portion that stops well before anterior end of upper
parietal; 3rd parietal very high on posterior third, expanded and
serrated above, with gradual anterior descension to a raised lamellar
ridge that terminates well beyond anterior end of upper parietal.
Columellar barrier a high bladelike lamella, weakly expanded and
serrated above, posteriorly lying parallel to plane of coiling, abruptly
descending anteriorly and twisted downward onto basal margin,
moderately expanded at anterior end. Palatal barriers 4, extending
posteriorly more than one-eighth whorl; lower palatal very high,
bladelike, expanded, flattened and serrated above, with abrupt
anterior descension almost to lip margin, weakly expanded at
anterior edge; 2nd and 3rd palatals equally high posteriorly,
expanded and serrated above, with more gradual anterior descension;
4th palatal supraperipheral, lying above plane of upper parietal,
greatly reduced in height and length, a low, lamellar blade, with very
gradual anterior descension. Height of holotype 2.01 mm., diameter
3.26 mm.
Holotype. — Austral Islands: Rapa Island, Station
477, northwest of Mt. Tautautu at 800 ft. elevation,
above Station 340. Collected under stones by S. Wight,
Yoshio Kondo, and C. M. Cooke, Jr. on July 25, 1934.
BPBM 144711.
Range. - Northwest of Mt. Tautautu at 750-800
ft. elevation, Rapa Island, Austral Islands.
Paratypes. — Same as list of material.
Material. — Rapa Island: northwest of Mt.
Tautautu (Stations 477, 478) at 750-800 ft. elevation
under stones (19 specimens, BPBM 144711-4, BPBM
143299).
Remarks. — The type of O. areaensis densa is
slightly atypical in that the middle parietal barrier has
the low anterior portion missing, although the
posterior elevation is identical to that found in the
nominate race. This variation was found in two of the
19 specimens. All specimens of O. a. densa have a
strongly differentiated color pattern of alternating
horn and reddish markings, while most O. areaensis
areaensis are indistinctly flammulated or tend toward
a unicolored condition.
Specimens of O. a. densa are immediately sepa-
rable from neighboring populations by their crowded
ribbing and elevated spire. Although the O. areaensis
areaensis taken from Stations 316 and 317 have
equally elevated spires, their ribbing is the type found
in the nominate race.
Description of soft parts. — Foot and tail completely retracted
in all available material. Sole, when dissected out, undivided, pedal
grooves typical.
Body color yellowish white, no darker markings.
Mantle collar typical.
Pallial region extending apically slightly more than one-half
whorl. Lung roof clear, without granulations. Kidney and ureter
typical.
Genitalia as in nominate race, except penis shorter (2.15 mm.
long), with roughly equal pilasters. Vas deferens entering penis
almost at apex.
Jaw not successfully mounted.
Radula fragmented in mounting, teeth as in O. areaensis
areaensis.
(Based on BPBM 144711, whole specimen 3.30 mm. in diameter,
with 5'/2 whorls and 92 ribs on the body whorl.)
Opanara areaensis microtorma, new sub-
species. Figure 104e-f.
Diagnosis. — Shell larger than average, diameter 3.54-3.64 mm.
(mean 3.60 mm.), with 5'/2 - 6 normally coiled whorls. Apex and spire
slightly and evenly elevated, last whorl descending a little more
rapidly, H/D ratio 0.551-0.607 (mean 0.584). Umbilicus open, U-
shaped, last whorl slightly decoiling, contained 3.86-4.27 times (mean
4.11) in the diameter. Postnuclear sculpture of narrow, prominent,
lamellar, slightly protractively sinuated radial ribs, 73-83 (mean 77.0)
on the body whorl, whose interstices are 3-4 times their width.
Microsculpture of fine radial riblets, four to seven between each pair
of major ribs, crossed by exceedingly fine and crowded spiral riblets.
Sutures deep, whorls strongly rounded above, with evenly rounded
and somewhat compressed outer margin, umbilical margin strongly
shouldered, columellar wall flattened. Aperture ovate, compressed
laterally, inclined about 5° from shell axis. Parietal barriers as in the
nominate subspecies, except that three of the five known specimens
have the anterior threadlike portion of the middle parietal distinctly
shortened. Columellar and palatal barriers as in the nominate
subspecies.
A distinctly elevated spire, slightly more numer-
ous ribbing, and narrower umbilicus are the characters
that separate Opanara areaensis microtorma from the
nominate subspecies. O. a. densa differs in its wider
umbilicus, much more crowded radial ribbing, and
slightly more elevated spire.
Description. — Shell larger than average, with 534 normally
coiled whorls. Apex and spire slightly and evenly elevated, last whorl
descending a little more rapidly, H/D ratio 0.607. Apical and early
postnuclear whorls with sculpture eroded. Remaining whorls with
narrow, prominent, lamellar, slightly protractively sinuated radial
ribs, 75 on the body whorl, whose interstices are 3-4 times their
width. Microsculpture of fine radial riblets, four to seven between
each pair of major ribs, crossed by extremely crowded, barely visible
spiral riblets. Sutures deep, whorls strongly rounded above,
246
SOLEM: ENDODONTOID LAND SNAILS
compressed laterally on gently rounded outer margin, umbilical
margin strongly shouldered, columellar wall somewhat flattened.
Color light yellow horn, with irregular, narrow, somewhat zigzagged,
reddish flammulations that tend to fade out on shell base. Umbilicus
narrow, U-shaped, last whorls barely decoiling, contained 4.15 times
in the diameter, umbilical margin strongly shouldered. Aperture
ovate, slightly compressed laterally, inclined about 5° from shell axis.
Parietal barriers 3, extending posteriorly more than three-six-
teenths of a whorl; upper parietal high and bladelike, expanded
and serrated above on posterior third, with very gradual anterior
descension until just before anterior eighth of length; 2nd parietal
with posterior quarter high and bladelike, somewhat expanded above
and crescentic in outline, sharply descending to a narrow threadlike
trace that terminates well before end of upper parietal; 3rd parietal
high and bladelike, expanded and serrated above on posterior third,
with very gradual descension to a low lamellar ridge that terminates
beyond anterior end of upper parietal. Columellar barrier a high
slender ridge, posteriorly parallel to plane of coiling, expanded and
serrated above, anteriorly twisting abruptly downward onto lip
margin, grossly expanded at anterior end. Palatal barriers 4,
extending posteriorly slightly more than one-eighth whorl: lower
palatal high and bladelike, flattened, serrated and expanded above,
with abrupt anterior descension almost to lip margin, weakly
expanded at anterior end; 2nd and 3rd palatals equal in height to
1st, expanded and serrated above on posterior half with progressively
more gradual anterior descension; 4th palatal supraperipheral,
greatly reduced in height and length, moderately recessed within
aperture, lying above plane of upper parietal, a low lamellar ridge.
Height of holotype 2.14 mm., diameter 3.52 mm.
Holotype. — Austral Islands: Rapa Island, Station
509, east ridge of Mt. Perahu at 1,300-1,500 ft.
elevation. Collected by Yoshio Kondo, Donald An-
derson and natives on July 28, 1934. BPBM 135437.
Range. - East ridge of Mt. Perahu at 1,200-1,800
ft. elevation, Rapa Island, Austral Islands.
Paratypes. — Same as list of material.
Material. — Rapa: east ridge of Mt. Perahu
(Stations 446, 451, 452, 509) at 1,200-1,800 ft. elevation
(5 specimens, BPBM 135437, BPBM 142746, ex BPBM
142818, BPBM 142875).
Remarks. — So little material is available, that no
real systematic importance can be attached to the 60
per cent incidence of shortening in the 2nd parietal.
This was sometimes (11.1 per cent) present in O. a.
densa, based on very limited material, and in O.
areaensis areaensis was not observed in any specimen.
As in O. areaensis densa, the flammulated color
pattern was strongly developed. Despite the presence
of a narrowly umbilicated population (Stations 316,
317) in O. areaensis areaensis, the narrow umbilicus
of O. a. microtorma combined with the raised spire
and generally more crowded ribbing serve to character-
ize it as a recognizable taxonomic unit.
Opanara caliculata, new species. Figure 105a-b.
Diagnosis. - Shell slightly smaller than average, diameter 3.09-
3.39 mm. (mean 3.27 mm.), with 4% - 5'/4 tightly coiled whorls. Shell
sub-globose, apex and spire moderately and evenly elevated, last
whorl descending only slightly more rapidly, H/D ratio 0.595-0.660
(mean 0.617). Umbilicus narrow, U-shaped, slightly narrower at last,
whorl than near apex, contained 4.09-5.22 times (mean 4.74) in the
diameter. Postnuclear sculpture of narrow, lamellate, very crowded,
slightly protractively sinuated radial ribs, 117-125 (mean 120.3) on
the body whorl, whose interstices are about twice their width.
Microsculpture of fine radial riblets, three to five between each pair
of major ribs, crossed by much finer and more crowded spiral riblets.
Sutures deep, whorls strongly and evenly rounded on outer margin,
basal margin slightly flattened and extended, baso-columellar margin
strongly angled, columellar wall weakly sinuated. Aperture ovate,
with evenly rounded outer margin, columellar margin flattened and
sinuated, inclined about 15° from shell axis. Parietal barriers 3,
extending posteriorly about three-sixteenths of a whorl: upper
parietal high and bladelike, expanded and serrated above on
posterior half, with very gradual anterior descension; 2nd parietal
slightly higher posteriorly, roughly crescentic on elevated portion
that occupies posterior third of length, rather gradually descending
to raised threadlike anterior portion that extends beyond end of
upper parietal; 3rd parietal slightly reduced in height from 2nd,
posterior elevated portion similar in shape but shorter, anterior
threadlike portion of equal length. Columellar barrier a low,
bladelike lamellar ridge, lying parallel to plane of coiling posteriorly,
slanting very slightly downward at anterior end, reaching almost to
lip margin. Palatal barriers 4, extending posteriorly about one-eighth
whorl; 1st palatal a high, crescentic lamellar blade, weakly expanded
and serrated above, sharply descending anteriorly almost to lip
margin; 2nd palatal equal in height to 1st, with more gradual
anterior descension; 3rd palatal slightly reduced in height with even
more gradual anterior descension; 4th palatal greatly reduced in
height; an elevated lamellar ridge, weakly expanded and serrated
above, situated slightly above level of upper parietal, more deeply
recessed within aperture.
The subglobose form, umbilicus that narrows
during the last two whorls of growth, and very
crowded radial ribbing at once separate Opanara
caliculata from the other Rapan species. The very
similar Opanara altiapica differs in its much higher
spire, less crowded ribbing, and smaller size. All other
Opanara have at most slightly elevated spires and
lack the umbilical margining.
Description. — Shell of average size, subglobose, with 5W rather
tightly coiled whorls. Apex and spire moderately and almost evenly
elevated, slightly rounded above, last whorl descending more rapidly,
H/D ratio 0.660. Embryonic whorls l'/2, sculpture of fine radial
riblets, with finer microriblets in between and rather widely spaced
spiral riblets. Postnuclear whorls with narrow, lamellate, crowded,
slightly protractively sinuated radial ribs, 125 on the body whorl,
whose interstices are about twice their width. Microsculpture of fine
radial riblets, three to five between each pair of major ribs, crossed
by much finer and more crowded spiral riblets. Sutures deep, whorls
strongly rounded on outer margin, baso-columellar margin an-
gulated, columellar wall flattened and slightly sinuated. Ground
color light yellow-white, lower portion of spire with vague
alternating reddish and yellow-white flammulations, body whorl a
light yellow-brown with only vague remnants of flammulations.
Umbilicus narrow, U-shaped, wider near apex than at last whorl,
contained 4.91 times in the diameter. Slight constriction accom-
plished by narrowing of coiling pattern in last two whorls. Aperture
ovate, with flattened and sinuated columellar margin, inclined about
15° from shell axis. Parietal barriers 3, extending posteriorly about
three-sixteenths of a whorl: upper parietal high and bladelike,
expanded and serrated above on posterior half, with very gradual
anterior descension; 2nd parietal with elevated posterior portion
almost crescentic, more strongly expanded above and shorter than in
1st parietal, with rather gradual descension to threadlike anterior
half that extends beyond end of upper parietal; 3rd parietal slightly
shorter and lower in elevated portion than 2nd, anterior threadlike
portion equal in length. Columellar barrier a raised lamellar ridge,
expanded and serrated above posteriorly, twisting slightly
downwards during its anterior descension and almost reaching edge
of columellar lip. Palatal barriers 4, extending posteriorly about one-
eighth whorl, expanded and serrated above posteriorly, with gradual
SYSTEMATIC REVIEW
247
anterior descension until just before anterior end when descension
becomes abrupt; 2nd palatal equal in height, elevated posterior
portion shorter, with more gradual anterior descension; 3rd palatal
reduced in height, with very short expanded posterior portion and
very gradual anterior descension; 4th palatal slightly supraperipheral
in position, greatly reduced in height and length, situated slightly
above level of upper parietal. Height of holotype 2.24 mm., diameter
3.39mm.
Holotype. — Austral Islands: Rapa Island, Station
453, east ridge of Mt. Perahu at 1,800-1,900 ft.
elevation. Collected by Yoshio Kondo on July 21, 1934.
BPBM 142908.
Range. - West ridge of Mt. Perahu at 1,500-1,900
ft. elevation, Rapa Island, Austral Islands.
Paratypes. — Same as list of material.
Material. — Rapa Island: east ridge of Mt. Perahu
(Stations 453, 512) at 1,500-1,900 ft. elevation (8
specimens, BPBM 142908, ex BPBM 135484, ex BPBM
135487-8).
Remarks. — The figured holotype is one of the
more elevated specimens and approaches the shape of
Opanara altiapica. Rather than prepare duplicate
drawings, this somewhat atypical example was re-
tained as type specimen.
The few available specimens showed no significant
variation in ribbing, umbilical configuration or aper-
tural barriers. Differences from the closely related O.
altiapica, found on Mt. Mangaoa, are both anatomical
and conchological. Comparing all adults of O. calicu-
lata with adults of O. altiapica from Station 526, with
9 df, "t" = 4.3201 for diameter and 4.1297 for H/D
ratio. The differences in rib count and rib frequency
(tables LXXV, LXXVII) are so large that no test of
significance is necessary. In O. caliculata the penis
lacks a fleshy extension to the head and the penis is
much thicker and shorter than in O. altiapica.
Description of soft parts. — Two partly extracted animals, one
subsequently squashed flat, were available. Foot and tail typical in
shape, tapering slightly posteriorly, bluntly rounded behind. Sole
undivided. Pedal grooves high on foot, suprapedal much weaker than
pedal, distance between equal to distance between bottom of foot
and lower groove, no caudal horn or middorsal groove present. Slime
network weak except on sides of foot, typical. Head projecting well
in front of bluntly truncated foot. Ommatophores long, eyespot
small and black, with a brownish suffusion in surrounding muscle.
Gonopore located slightly above and a little behind right rhinophore,
well behind and below right ommatophore.
Body color light yellow-white, no darker markings.
Mantle collar with thickened edges, no glandular extension onto
pallial roof.
Pallial region absent except for anterior quarter of lung roof in
available specimens. Kidney, ureter, heart, and principal pulmonary
vein not seen.
FIG. 105. a-b, Opanara caliculata, new species. Station 453, Mt.
Perahu, Rapa Island, Austral Islands. Holotype. BPBM 142908; c,
O. altiapica, Station 526, Mt. Mangaoa, Rapa Island, Austral
Islands. Holotype. BPBM 143741. Scale lines equal 1 mm. Figures a-
b, by YK reproduced through the courtesy of Bernice P. Bishop
Museum; c (PR).
ab
248
SOLEM: ENDODONTOID LAND SNAILS
Only terminal genitalia studied. End of prostate and uterus
typical. Vas deferens inserting subapically on penis, opening between
two pilasters. Penial retractor apparently inserting directly on apex
of penis, no sign of a fleshy penis extension. Penis about 2.0-2.7 mm.
long, much fatter than in Opanara altiapica. sharply tapering
apically, internally with same two pilasters, larger grossly expanded,
very high medially, gradually descending and narrowing apically,
basally broadening and slightly lowering, with apical fusion just
below insertion of penial retractor.
Free oviduct tapering, internally glandularized near union with
spermatheca, whose shaft widens just before union. Free muscle
system with right ommatophoral retractor passing through peni-
oviducal angle.
Jaw not successfully mounted.
Radula with 5 laterals, marginals broken off, centrals about 11 fi
square.
(Based on BPBM 142908, two examples previously extracted
from shell.)
Opanara altiapica, new species. Figures 97a-b; 105c.
Diagnosis. — Shell very small, diameter 2.63-3.03 mm. (mean
2.82 mm.), with 4% - 5% tightly coiled whorls. Shell globose, apex and
spire moderately and evenly elevated, last whorl descending only
slightly more rapidly, H/D ratio 0.664-0.761 (mean 0.719). Umbilicus
narrow, U-shaped, slightly wider at apex than at last whorl,
contained 3.91-5.53 times (mean 4.69) in the diameter. Postnuclear
sculpture of narrow, lamellate, rather crowded, protractively sin-
uated radial ribs, 64-91 (mean 80.0) on the body whorl, whose
interstices are 3 - 4 times their width. Microsculpture of fine radial
riblets, four to seven between each pair of major ribs, crossed by
much finer and more crowded spiral riblets. Sutures impressed,
whorls strongly and evenly rounded on outer margins, baso-
columellar margin sharply angulated, with a distinct columellar
sulcus, inner wall of columella flattened. Aperture ovate, baso-
columellar margin sharply angulated, inclined about 5° from shell
axis. Parietal barriers 3, extending posteriorly about three-sixteenths
of a whorl: upper parietal high and bladelike, expanded and serrated
above on posterior half, with gradual anterior descension; 2nd
parietal almost crescentic on elevated posterior portion, equally high
as 1st, with gradual anterior descension to a threadlike anterior half
that extends beyond end of upper parietal; 3rd parietal equal in
height and shape to 2nd, extending slightly further anteriorly.
Columellar barrier a high bladelike ridge posteriorly, expanded and
serrated above, twisting diagonally downward across columellar wall
and almost reaching lip margin. Palatal barriers 4, extending
posteriorly about one-eighth whorl: lower palatal very high,
expanded, and serrated above on central portion, with very sharp
anterior descension, moderately recessed within aperture; 2nd palatal
slightly reduced in height, expanded portion shorter, with slightly
more gradual anterior descension until just before anterior end; 3rd
palatal slightly reduced in height from 2nd, expanded portion
shorter, with gradual anterior descension; 4th palatal slightly
supraperipheral in position, greatly reduced in height, an elevated
lamellar ridge, deeply recessed within aperture.
The much smaller size, greater H/D ratio, and the
more widely spaced radial ribbing immediately sepa-
rate Opanara altiapica from the obviously related O.
caliculata. No other Rapan species have such an
elevated spire.
Description. — Shell small, with 5V4 tightly coiled whorls. Apex
and spire strongly elevated, rounded above, last whorl descending
slightly more rapidly. H/D ratio 0.761. Apical whorls 1%, sculpture
eroded. Postnuclear whorls with narrow, lamellate, rather crowded,
protractively sinuated radial ribs. 82 on the body whorl, whose
interstices are 3-4 times their width. Microsculpture of fine radial
riblets, four to seven between each pair of major ribs, crossed by
exceedingly fine and crowded spiral riblets. Sutures impressed,
whorls strongly and evenly rounded on outer margin, columellar wall
flattened with a distinct columellar sulcus. Color mainly leached
from shell, light yellow-brown epidermis remaining, with vague
traces of irregular reddish flammulations visible above periphery on
antipenultimate whorl. Umbilicus narrow, U-shaped, wider apex
than on last whorl, contained 5.12 times in the diameter. Aperture
ovate, with evenly rounded outer margins, baso-columellar margin
angulated, inclined about 5° from shell axis. Apertural barriers as
outlined above under diagnosis. Height of holotype 2.30 mm.,
diameter 3.02 mm.
Holotype. — Austral Islands: Rapa Island, Station
526, northeast ridge of Mt. Mangaoa at 1,000-1,100 ft.
elevation. Collected by Elwood Zimmerman and
Donald Anderson on July 19, 1934. BPBM 143741.
Range. - Mt. Mangaoa at 1,000-1,200 ft. elevation,
Rapa Island, Austral Islands.
Paratypes. — Same as list of material.
Material. — Rapa Island: northeast peak and
ridge of Mt. Mangaoa (Stations 481, 526) at 1,000-1,200
ft. elevation (24 specimens, BPBM 143335, BPBM
143741-6).
Remarks. — No significant variation was observed
in the apertural barriers or ribbing. Anatomically, O.
altiapica is quite generalized, the great size reduction
of one pilaster being the only specialization over the
typical Opanara pattern.
Relationship between O. altiapica and O. calicu-
lata is of the same kind as between O. m. megomphala
and O. m. tepiahuensis. Subspecific recognition in the
second case was decided on in the absence of any
anatomical distinctions between the morphs and
distinctly smaller conchological differences than in the
first pair. The conchological differences between O.
caliculata and O. altiapica are caused by the tighter
coiling and greater spire elevation of the latter. Shell
height and D/U ratio are essentially identical.
Description of soft parts. — Foot and most of tail pulled off
previous to study, presumably in routine processing.
Body color light yellow-white, no darker markings.
Mantle collar typical, no glandular extension onto pallial roof.
Pallial region extending three-quarters of a whorl apically. Lung
roof clear except for clusters of white granules along pulmonary vein
and kidney. Kidney about 1.45 mm. long, rectal arm about one-third
length of pericardial. Ureter typical. Heart about one-third length of
kidney, not lying parallel to hindgut. Principal pulmonary vein
slender, bordered by white granules, stopping short of mantle collar.
Hindgut slender, following parietal-palatal margin to union of
esophagus and stomach.
Ovotestis (fig. 97a, G) imbedded in digestive gland above
stomach reflexion, composed of many palmately clavate alveoli that
are slightly iridescent with indications of developing ova (?) in some.
Hermaphroditic duct (GD) relatively narrow to moderately ex-
panded, narrowing and sharply reflexing before entering talon.
Albumen gland (GG) typical, much larger than talon, rather poorly
preserved in available material. Talon (GT) typical in form, buried in
albumen gland. Prostate (DG) of two rows of large acini opening
into a narrow duct, slightly shorter than uterus and not as long as
free oviduct. Uterus (UT) typically divided into two sections.
Vas deferens (VD) inserting subapically in penis, opening (DP)
between penial pilasters. Penial retractor (PR) originating on
diaphragm, inserting on fleshy head of penis. Penis (P) about 1.8-2.1
SYSTEMATIC REVIEW
249
mm. long, tapering apically, internally with two pilasters (PP) of
highly unequal size (fig. 97b), one reduced to a low trace and
terminating medially, the other very large and high, slowly
descending both apically and basally from point slightly above
middle. Atrium (Y) rather wide and short.
Free oviduct (UV) tapering sharply at first, widening again at
basal portion just before spermathecal junction. Spermatheca (Si
with typical head and early shaft, expanding basally before joining
free oviduct. Vagina (V) not differentiated structurally.
Free muscle system typical, right ommatophoral retractor
passing through penioviducal angle. Buccal mass, esophagus,
stomach and intestinal coiling typical. Buccal retractors not split,
uniting with tail fan just before end of columellar muscle.
Jaw not successfully mounted.
Radula with about 6 laterals, central about 10u wide and ll,u
long.
(Based on BPBM 143742, several fragmentary and squashed
examples.)
Opanara megomphala, new species.
Populations referred to this species were seen from
Mt. Tepiahu and Mt. Tautautu at 500-800 ft.
elevation. They are separable into two morphs that do
not overlap in respect to H/D or D/U ratios.
Specimens from Mt. Tautautu (O. megomphala me-
gomphala) are higher, with a greater H/D ratio, a
narrower umbilicus, and a more strongly angulated
umbilical margin than examples from Mt. Tepiahu (O.
megomphala tepiahuensis). Although there are aver-
age differences in rib count (table LXXV) and rib
frequency (table LXXVII), the overlap is so large
that these characters cannot be utilized to separate
individuals of the two forms.
The difference in mean diameter (4.7 per cent) is
small, but the changes in H/D ratio (17.8 per cent)
and D/U ratio (13.8 per cent) are dramatic. Both are
linked to the change in shell height, a difference of 12.3
per cent. The greater shell height at a given diameter
is reflected in an increase in the H/D ratio and a
narrowing of the umbilicus caused by the tighter
coiling. The differences are statistically significant
when comparing populations (for Station 477 megom-
phala megomphala and Station 459 m. tepiahuensis,
with 27 df: "t" = 2.4804 for height; "t" = 2.3989 for
diameter; "t" = 5.5600 for H/D ratio; and "t" =
6.8650 for D/U ratio). While the changes height and
diameter are below the conventional level of subspe-
cific difference (C.D. equals 0.5347 and 0.5526, respec-
tively), there is no question but that the H/D and
D/U ratios indicate subspecific separation (C.D. equals
1.367 and 1.687, respectively).
No differences in apertural barriers were detected.
The very widely open umbilicus, and reduction of
all apertural barriers to threadlike traces immediately
separate O. megomphala from all Rapan species.
Similar reduction of the parietal barriers is seen in
Australdonta radiella and the Hawaiian Nesophila,
but both of the latter lack all palatal and columellar
barriers. The Marquesan species, Taipidon centaden-
tata and Planudonta intermedia have partial splitting
of the apertural barriers, but not nearly as much as in
Opanara megomphala.
Opanara megomphala megomphala, new species
and subspecies. Figures 97c-d; 106a-b.
Diagnosis. — Shell of slightly less than average size, diameter
2.83-3.52 mm. (mean 3.21 mm.), with 5'/4-6'/*i relatively tightly
coiled whorls. Apex and early spire flat or slightly depressed, last two
whorls descending distinctly more rapidly, H/D ratio 0.486-0.564
(mean 0.511). Umbilicus very widely open, cup-shaped, last whorls
not decoiling more rapidly, contained 2.15-2.35 times (mean 2.22) in
the diameter. Postnuclear sculpture of high, prominent, rather
crowded, vertically sinuated radial ribs, 71-76 (mean 73.7) on the
body whorl, whose interstices are 2-4 times their width. Micro-
sculpture of extremely fine radial riblets, seven to twelve between
each pair of major ribs, crossed by slightly finer and more crowded
spiral riblets. Sutures deep, whorls strongly rounded above, outer
margin evenly rounded and slightly compressed, umbilical margin
strongly rounded, columellar margin flattened. Aperture ovate, outer
margin slightly compressed, evenly rounded, inclined less than 5°
from shell axis. Parietal wall with four to six threadlike traces, two
or three of which may be weakly elevated, all extending posteriorly
beyond line of vision, often with up to three short, lower, recessed
accessory traces. Columellar and palatal wall with many fine and
crowded threadlike traces that extend almost one-quarter whorl
posteriorly.
The reduction of all apertural barriers to
elongated, threadlike-traces at once distinguishes Opa-
nara megomphala from all other Endodontidae. The
Austral Islands Australdonta radiella (Pfeiffer) and
the Hawaiian Nesophila differ in total lack of palatal
or columellar barriers, although sharing similar parie-
tal barriers. The extremely wide umbilicus of Opanara
megomphala at once separates it from all other Rapan
species. The nominate subspecies differs from O.
megomphala tepiahuensis by its narrower umbilicus
and much higher spire.
Description. — Shell of average size, with 6 rather tightly coiled
whorls. Apex and early spire sunken beneath top of antipenultimate
whorl, last two whorls descending much more rapidly, H/D ratio
0.525. Embryonic whorls l'/2, sculpture of fine radial ribs interspersed
with finer radial riblets, crossed by finer and slightly more crowded
spiral riblets. Postnuclear whorls with prominent, rather crowded,
almost vertically sinuated radial ribs, 76 on the body whorl, whose
interstices are 2-4 times their width. Microsculpture of extremely fine
radial riblets, seven to twelve between each pair of major ribs,
crossed by finer and more crowded spiral riblets. Sutures deep,
whorls strongly rounded above, compressed laterally, outer margin
evenly rounded, baso-columellar margin sharply angulated, colu-
mellar wall distinctly flattened. Color light yellow-white, with
irregularly zigzagged, reddish flammulations that tend to coalesce
near shell periphery. Umbilicus broadly open, cup-shaped, last
whorls not decoiling more rapidly, contained 2.19 times in the
diameter, umbilical margin strongly angulated, inner whorls
flattened. Aperture ovate, compressed laterally, inclined less than 5°
from shell axis. Parietal wall with six threadlike traces that extend
posteriorly beyond line of vision, one trace deeply recessed within
aperture, two traces slightly more elevated than the others.
Columellar and palatal walls with numerous fine, crowded, deeply
recessed, threadlike traces that extend posteriorly for one-quarter
whorl. Height of holotype 1.74 mm., diameter 3.33 mm.
Holotype. — Austral Islands: Rapa Island, Station
477, hillside northwest of Mt. Tautautu (above Station
250
SOLEM: ENDODONTOID LAND SNAILS
FIG. 106. a-b, Opanara megomphala megomphala, new species and subspecies. Station 477, Mt. Tautautu, Rapa Island, Austral Islands.
Holotype. BPBM 144717; c-d, Opanara megomphala tepiahuensis , new subspecies. Station 459, Mt. Tepiahu, Rapa Island, Austral Islands.
Holotype. BPBM 143003. Scale lines equal 1 mm. Drawings by YK reproduced through the courtesy of Bernice P. Bishop Museum.
340) at 800 ft. elevation, under stones and logs.
Collected by S. Wight, Yoshio Kondo, and C. M.
Cooke, Jr. on July 25, 1934. BPBM 144717.
Range. — Northwest of Tautautu at 800 ft.
elevation and above Maitua at 500 ft. elevation, Rapa
Island, Austral Islands.
Paratypes. — Same as list of material.
Material. — Rapa Island: northwest of Tautautu
(Station 477) at 800 ft. elevation (5 specimens, BPBM
144717-8); coffee plantation above Maitua (Station
427) at 500 ft. elevation (9 specimens, BPBM 135529-
31).
Remarks. — The palatal and columellar traces are
too fine and crowded for accurate counts to be made.
No significant variation in apertural barriers or
sculpture was noted. Unfortunately, only fragmentary
soft parts of paraneanic individuals were available.
Description nf soft parts. — The terminal male genitalia (fig.
97c-d) shows the same pilaster and vas deferens entrance pattern
observed in O. m. tepiahuensis. The relatively small size of the penis,
length about 1.75 mm., probably is only a function of age.
(Based on BPBM 144718.)
Opanara megomphala tepiahuensis, new sub-
species. Figures 97e-f; 106c-d.
Diagnosis. — Shell of average size, diameter 2.98-3.77 mm. (mean
3.36 mm.), with 5' 2 - 6Vs tightly coiled whorls. Apex and early spire
slightly depressed below level of antipenultimate whorl, last two
whorls descending slightly. H/D ratio 0.353-0.481 (mean 0.434).
Umbilicus extremely widely open, cup-shaped, regularly decoiling,
contained 1.72-2.08 times (mean 1.95) in the diameter. Postnuclear
sculpture of prominent, almost vertically sinuated, rather widely
spaced ribs, 54-81 (mean 64.6) on the body whorl, whose interstices
are 4-6 times their width. Microsculpture of extremely fine radial
riblets, eight to twelve between each pair of major ribs, crossed by
very much finer and more crowded spiral riblets. Sutures deep,
whorls strongly rounded above, slightly compressed laterally, with
strongly rounded to angulated baso-columellar margin, columellar
wall somewhat flattened. Aperture ovate, slightly compressed
laterally, with sharply rounded and angulated baso-columellar
margin, inclined less than 5° from shell axis. Parietal wall with four
to six threadlike traces, extending posteriorly beyond line of vision,
sometimes with up to three short, deeply recessed accessory threads.
Columellar and palatal walls with fine, very crowded, deeply
recessed, threadlike traces, that extend posteriorly almost one-
quarter whorl.
SYSTEMATIC REVIEW
251
The lower spire, more widely open umbilicus with
regular decoiling of the last whorl, less strongly
angulated baso-columellar margin, and fewer, more
widely spaced radial ribs, combine to separate Opa-
nara megomphala tepiahuensis from the nominate
subspecies. No other Rapan shell can be confused with
it.
Description. — Shell slightly larger than average, with (i rather
tightly coiled whorls. Apex and early spire depressed below level of
antipenultimate whorl, last two whorls descending slightly, H/D
ratio 0.441. Apical whorls 1'j, sculpture typical. Postnuclear whorls
with narrow, prominent, rather widely spaced, vertically sinuated
radial ribs, 71 on the body whorl, whose interstices are 4-6 times
their width. Microsculpture of extremely fine radial riblets, eight to
twelve between each pair of major ribs, crossed by finer and more
crowded spiral riblets. Sutures deep, whorls strongly rounded above,
compressed laterally, basal margin strongly angulated, columellar
wall somewhat flattened. Aperture ovate, slightly compressed
laterally, inclined less than 5° from shell axis. Parietal wall with six
low, threadlike traces that extend posteriorly beyond line of vision.
Columellar and palatal walls with many crowded, deeply recessed,
threadlike traces that extend posteriorly for about one-quarter
whorl. Height of holotype 1.38 mm., diameter 3.59 mm.
Holotype. — Austral Islands: Rapa Island, Station
459, south side of Mt. Tepiahu at 550 ft. elevation on a
hillside under stones and dead leaves. Collected by C.
M. Cooke, Jr. on July 23, 1934. BPBM 143003.
Range. - South side of Mt. Tepiahu, 500-550 ft.
elevation, Rapa Island, Austral Islands.
Paratypes. — Same as list of material.
Material. — Rapa Island: hillside on south side of
Mt. Tepiahu (Stations 458, 459) at 500-550 ft. elevation
(121 specimens, BPBM 142962-6, BPBM 143003-7).
Remarks. — The differences between shells of O.
m. megomphala and O. m. tepiahuensis are the same
order of magnitude as those between O. altiapica and
O. caliculata. The latter have been given specific
recognition because there are anatomical differences
between the conchologically similar forms. Only
subadult specimens of O. m. megomphala were
available, so that the smaller penis size reported above
has no significance.
Dissected individuals of O. m. tepiahuensis show-
rather simple pilaster patterns and almost apical
insertion of the vas deferens. Otherwise the anatomy is
typical of Opanara.
Description of soft parts. — Foot and tail partly retracted in all
available material, end of tail rounded behind, not tapering. Sole
undivided. Pedal grooves typical, rather high on foot, no caudal horn
or middorsal groove. Slime network very faint.
Body color light yellow-white, without darker markings.
Mantle collar narrow and elongated, only slightly thickened, no
glandular extension onto mantle roof. Pneumostome and anal
opening typical.
Pallial region extending more than three-quarters whorl apically.
Lung roof clear, without granulations. Kidney a little less than 1.50
mm. long, rectal arm half length of kidney. Heart half length of
kidney, lying parallel to hindgut. Principal pulmonary vein very
slender, fading out before reaching mantle collar. Hindgut typical.
Ovotestis (fig. 97e, G) with five to six clumps of very elongated,
palmately clavate alveoli, upper clumps longer and more nearly
parallel to plane of coiling than anterior clumps. Hermaphroditic
duct (GD) greatly enlarged and nodose medially, very slender and
tapering at each end, reflexing sharply before joining talon. Albumen
gland (GG) small, without marked structural difference. Talon (GT)
with small globular head and long tapering shaft before entering
carrefour. Prostate (DG) with one to three rows of acini opening into
a narrow tube buried in folds of uterus, length of prostate less than
half the distance from carrefour to atrium. Uterus (UT) bipartite,
rather indistinctly separated, the lower portion passing without
external differentiation into free oviduct.
Vas deferens (VD) typical, not varying in diameter, moderately
coiled (because of contraction) near atrium, entering penis laterally,
about 0.25 mm. below apex of penis. Penial pore opening to outer
side, near attached edge, on one pilaster. Penial retractor (PR)
arising from diaphragm right at apex of pallial cavity, inserting
directly onto fleshy extension of penis head. Penis (P) about 2.0 -
2.70 mm. long, with a long, fleshy extension to the head, somewhat
swollen in upper third, tapering gradually until shortly before
atrium, when it becomes a very slender tube. Internally (fig. 97f),
penis with two pilasters, united above and below, very high and thin,
with variously folded surface. A long, fleshy head occupies up to
two-thirds of distance from penis head to end of penial retractor.
Atrium (Y) short and narrow.
Free oviduct (UV) not clearly differentiated from uterus, very
long and slender. Spermatheca (S) with slightly expanded, ovoid
head lying at base of albumen gland, slender shaft joining free
oviduct just at penioviducal angle. Vagina not a differentiated
region.
Free muscle system typical. Muscle strand from edge of mantle
collar to apex of columellar retractor particularly well defined.
Digestive system somewhat more elongated than usual, stomach
extending one full whorl apically, digestive glands extending two and
one half whorls above apex of ovotestis.
Jaw of 17 large, rectangular, overlapping plates, individual
plates one-quarter to one-third as wide as long.
Radula with about 6 laterals, outer marginals broken off, central
about 10ft long, 8ju wide.
(Based on BPBM 143003-4, four examples, only one complete.)
Opanara fosbergi, new species,
c-d.
Figures 97g; 107
Diagnosis. — Shell relatively large, diameter 3.61-4.01 mm.
(mean 3.77 mm.), extremely compressed apically and basally, with
5%-55/s normally coiled whorls. Apex and spire flat, last whorl and
one-half descending slightly, H/D ratio 0.330-0.375 (mean 0.344).
Umbilicus narrow, U-shaped, last whorls barely decoiling, with very
strongly rounded margins, contained 5.74-8.07 times (mean 7.10) in
the diameter. Postnuclear whorls with narrow, prominent, lamellar,
protractively sinuated, rather crowded radial ribs, 93-108 (mean
100.5) on the body whorl, whose interstices are 2-3 times their width.
Microsculpture of fine radial riblets, four to seven between each pair
of major ribs, crossed by extremely fine and crowded spiral riblets
that are barely visible under 96 x magnification, with a secondary
sculpture of low, crowded, spiral cords that are most clearly visible
above periphery and only occasionally detectable on shell l>ase.
Sutures deep, whorls strongly rounded above, flattened laterally
above evenly rounded periphery, lower palatal margin gently
rounded, basal margin flattened, columellar margin evenly rounded
then strongly inside umbilicus. Aperture compressedly ovate,
strongly rounded above on periphery and umbilical margin, flattened
laterally above periphery and strongly flattened basally, inclined
about 10° from shell axis. Parietal barriers 3, somewhat irregularly
placed within aperture, extending about three-sixteenths of a whorl:
upper parietal high and bladelike, expanded and serrated above on
posterior half, with very gradual anterior descension until last eighth
of length; 2nd parietal slightly recessed, posterior half only slightly
less elevated, equally expanded and serrated above posteriorly, with
rather sharp descension to low threadlike trace that occupies
FIG. 107. a-b, Opanara perahuensis, new species, a, Station 453 Mt. Perahu, Rapa Island, Austral Islands. Holotype. BPBM 142909; b,
Station 509, Mt. Perahu, Rapa Island, Austral Islands. Paratype. BPBM 1&5438; c-d, O. fosbergi, new species. Station 450, Mt. Perahu, Rapa
Island, Austral Islands. Holotype. BPBM 142808; e-f, Opanara depasoapicata, new species, e, Station 451, Mt. Perahu, Rapa Island, Austral
Islands. Holotype. BPBM 142820; /, paratype. BPBM 142820. Scale lines equal 1 mm. Figures a, c-e by YK reproduced through the courtesy of
Bernice P. Bishop Museum; b, ( (MM).
252
SYSTEMATIC REVIEW
253
anterior third of length and terminates well behind anterior end of
upper parietal; 3rd parietal deeply recessed within aperture, reduced
in height, equally expanded and serrated above, with gradual
anterior descension, without anterior threadlike trace, terminating
anteriorly opposite mid-point of upper parietal. One (of five)
specimens had a 4th parietal located between 2nd and 3rd.
Columellar wall reduced to a sharply curved narrow section by basal
compression of shell. Palatal wall with 5 prominent barriers,
extending posteriorly more than one-eighth whorl, lower probably
displaced columellar of related species: 1st palatal a broadly
rounded, low, deeply recessed ridge; 2nd palatal a high lamellar
blade, flattened, expanded and serrated above, moderately recessed,
with gradual descension over anterior third; 3rd and 4th palatals
distinctly higher than 2nd, more expanded and serrated above on
posterior half, with progressively more gradual anterior descension,
but only slightly deeper recession within aperture; 5th palatal
supraperipheral in position, reduced in height, an elevated bladelike
ridge, expanded and serrated above, with very gradual anterior
descension, lying above plane of upper parietal, not more deeply-
recessed within aperture than 4th palatal. The 2nd through 5th
palatals occupy the same positions within the aperture as normally-
occupied by four palatals in other species of Opanara.
The great two way compression of this shell has
resulted in extreme narrowing of the aperture, then
displacement and size change of the lower parietal and
columellar barriers. The narrow umbilicus, large
barriers, and very depressed spire immediately separate
Opanara fosbergi from all other Rapan species. Only
Opanara megomphala tepiahuensis could be confused
on the basis of shape, but that species has a very
widely open umbilicus and the apertural barriers
reduced to fine threadlike traces.
Description. — Shell rather large, extremely compressed basally,
with 5% normally coiled whorls. Apex and early spire flat, last two
whorls descending slightly, H/D ratio 0.375. Apical whorls l'/2,
sculpture eroded above, with characteristic combination of radial
and microspiral sculpture showing on first whorls inside umbilicus.
Postnuclear whorls with narrow, lamellar, rather crowded, protrac-
tively sinuated radial ribs, 93 on the body whorl, whose interstices
are 2-3 times their width. Microsculpture of fine radial riblets, four
to seven between each pair of major ribs, crossed by exceedingly fine
and crowded spiral riblets that are visible only under 96 X
magnification, with a secondary sculpture of low, rounded, quite
crowded spiral cords that are most clearly visible just above and
below body whorl periphery. Sutures deep, whorls strongly rounded
above, flattened laterally above evenly rounded periphery, lower
palatal margin evenly rounded, basal margin flattened, with
columellar wall strongly rounded into umbilicus. Color light yellow-
horn, with broad, irregular reddish flammulations that tend to
disappear on shell base. Umbilicus narrow, U-shaped, whorls barely
decoiling from apex, contained 7.00 times in the diameter. Aperture
compressedly ovate, strongly rounded above and on periphery,
flattened laterally above periphery and strongly flattened on
inwardly extended basal margin, inclined about 10° from shell axis.
Parietal barriers 3, situated as described above under "Diagnosis."
Columellar wall compressed to a narrow arc by basal shell
compression, columellar barrier deflected onto basal lip. Palatal wall
with five barriers, as described above under "Diagnosis." Height of
holotype 1.38 mm., diameter 3.68 mm.
Holotype. — Austral Islands: Rapa Island, Station
450, upper part of east ridge, Mt. Perahu, at 1,500-
1,900 ft. elevation. Collected at base of bird's nest fern
by Raymond Fosberg on July 21, 1934. BPBM 142808.
Range. - East ridge of Mt. Perahu at 1,300 - 1,900
ft. elevation, Rapa Island, Austral Islands.
Paratypes. — Same as list of material.
Material. — Rapa: east ridge of Mt. Perahu
(Stations 450, 509) at 1,300 - 1,900 ft. elevation (5
specimens, BPBM 142808, BPBM 135444).
Remarks. — Although presenting a quite different
appearance from the other Opanara, O. fosbergi is the
result of one basic alteration. Extreme top and bottom
compression of the whorls significantly affected the
H/D ratio, height and D/U ratio, displaced the
columellar barrier onto the basal lip, and probably
increased the diameter significantly. If the effects of
this single alteration are discounted, then O. fosbergi is
a rather unspecialized species.
Four specimens were taken by Raymond Fosberg
(Station 450), after whom this species was named, and
a single example by Yoshio Kondo (Station 509). Only
fragmentary anatomical material was available, with
the partly crushed terminal genitalia and an isolated
hermaphroditic duct confirming its classification in
Opanara.
Description of soft parts. — In addition to the figured terminal
genitalia (fig. 97g), a single hermaphroditic duct typical of Opanara
was present.
Penis (P) about 2.83 mm. long, tapering apically, with fleshy
head extension, internally with two typical pilasters. Penial retractor
(PR) very long and slender. Vas deferens (VD) entering subapically
on penis, well below and between union of pilasters. Spermatheca (S)
joining free oviduct almost at atrial junction. Remnant of free
oviduct (UV) and atrium (Y) typical. Radula and jaw not
successfully mounted. Fragmentary radula showed central to be only
5 ji wide and 8 /J. long.
(Based on fragmented material from BPBM 142808.)
Opanara perahuensis, new species. Figures 97h-i;
107a-b.
Diagnosis. — Shell relatively small, diameter 2.83-3.49 mm.
(mean 3.15 mm.), with 5'/4 - 5% normally coiled whorls. Apex and
spire moderately and almost evenly elevated, slightly rounded above,
last whorl descending a little more rapidly, H/D ratio 0.555-0.620
(mean 0.579). Umbilicus generally narrowly perforate, contained
15.3-47.0 times (mean 28.2) in the diameter, often (18.2 per cent)
closed. Postnuclear sculpture of low, prominent, narrow, protractive-
ly sinuated radial ribs, 55-64 (mean 61.8) on the body whorl, whose
interstices are 3-5 times their width. Microsculpture of rather large
radial riblets, three to six between each pair of major ribs, crossed by
barely visible and extremely crowded spiral riblets. Sutures im-
pressed, whorls strongly rounded above, with evenly rounded outer
margins, strongly rounded to umbilicus. Aperture subcircular, with
evenly rounded outer margins, inclined less than 10° from shell axis.
Parietal barriers 3, extending posteriorly slightly more than three-
sixteenths of a whorl: upper parietal high and bladelike, expanded
and weakly serrated above on posterior quarter, with very gradual
anterior descension; 2nd parietal high and crescentic for posterior
eighth, with rather sharp descension to anterior threadlike five-
eighths, that extends anteriorly beyond end of upper parietal; 3rd
parietal similar in shape to 2nd, slightly shorter and less elevated
posteriorly, with equal anterior termination. Columellar wall with a
single raised threadlike ridge, becoming broadly lamellate posteriorly,
twisting slightly downward from plane of coiling, but stopping short
of lip edge. Palatal barriers 4, extending posteriorly slightly more
than one-eighth whorl, relatively low; 1st palatal basal in position,
an elevated bladelike lamella, weakly expanded and serrated above,
flattened on top, with gradual anterior descension until just before
reaching lip margin; 2nd palatal slightly higher, more broadly
expanded, serrated and flattened above, with gradual anterior
descension, slightly more deeply recessed; 3rd palatal reduced in
254
SOLEM: ENDODONTOID LAND SNAILS
height, expanded and serrated above only on posterior portion with
gradual and even anterior descension, moderately deeply recessed;
4th palatal peripheral in position, shortened, reduced in height,
deeply recessed, a raised threadlike ridge situated almost opposite
upper parietal.
Opanara perahuensis differs from O. bitridentata
in having fewer and less crowded radial ribs, a much
narrower umbilicus, higher spire, and always 3 pariet-
als. Only the very depressed (H/D ratio 0.330-0.375) O.
fosbergi has an umbilicus even approaching that of O.
perahuensis, while all other Opanara have widely
open umbilici. The 3 parietals effectively distinguish O.
perahuensis from any species of Orangia, while the
smaller size at a given whorl count and much more
prominent barriers separate it from any Ruatara.
Description. — Shell relatively small, with 5'/2 normally coiled
whorls. Apex and spire moderately and almost evenly elevated,
slightly rounded above, last whorl descending more rapidly, H/D
ratio 0.564. Apical whorls 1%, sculpture eroded. Postnuclear whorls
with narrow, low, rather widely spaced, protractively sinuated radial
ribs, 63 on the body whorl, whose interstices are 3-5 times their
width, and often with periostracal extensions. Microsculpture of
rather prominent radial riblets, three to six between each pair of
major ribs, crossed by exceedingly fine and crowded spiral riblets.
Sutures impressed, whorls strongly rounded above, with almost
evenly rounded outer margins and gently rounded baso-umbilical
margin. Color light yellow-horn, with relatively narrow, somewhat
indistinct, zigzagged, reddish flammulations that tend to coalesce on
shell base. Umbilicus narrowly perforate, open to apex, contained 25
times in the diameter. Aperture subcircular, with evenly rounded
outer margin, inclined about 10° from shell axis. Parietal barriers 3,
extending posteriorly about three-sixteenths of a whorl: upper
parietal a high bladelike lamella, weakly expanded and serrated
above on posterior quarter, with very gradual anterior descension;
2nd parietal with posterior quarter a high crescentic blade, rather
sharply descending to anterior five-eighths that is low and
threadlike, extending anteriorly beyond end of upper parietal; 3rd
parietal the same as 2nd, slightly reduced in height posteriorly.
Columellar barrier a high lamellar ridge, broadly expanded above
posteriorly with gradual anterior descension, twisted slightly
downward from plane of coiling and stopping short of lip edge.
Palatal barriers 4, extending about one-eighth whorl: lower palatal
basal in position, a moderately elevated lamellar ridge with gradual
anterior descension almost to lip edge, weakly expanded and serrated
above; 2nd palatal distinctly higher, more strongly expanded and
serrated above, flattened posteriorly, with more gradual anterior
descension; 3rd palatal distinctly reduced in height, expanded and
serrated above near posterior end, with gradual and even anterior
descension; 4th palatal reduced in height and length, moderately
deeply recessed, an elevated lamellar ridge, with very gradual
anterior descension, lying almost opposite upper parietal. Height of
holotype 1.87 mm., diameter 3.32 mm.
Holotype. — Austral Islands: Rapa Island, Station
453, east ridge of Mt. Perahu at 1,800-1,900 ft.
elevation. Collected by Yoshio Kondo on July 21, 1934.
BPBM 142909.
Range. - East ridge of Mt. Perahu at 1,200-1,900
ft. elevation, Rapa Island, Austral Islands.
Paratypes. — Same as list of material.
Material. - - Rapa: east ridge of Mt. Perahu
(Stations 446, 452, 453, 509) at 1,200-1,900 ft. elevation
(12 specimens, BPBM 1354138, BPBM 142750, BPBM
142880, BPBM 142909).
Remarks. — Of the species found at the same
localities, Opanara perahuensis is most apt to be
confused with O. bitridentata and Ruatara oparica.
The former has a much more widely open umbilicus
(D/U ratio 3.58-8.45), several accessory palatal bar-
riers, and a much less elevated spire, while the latter
has much shorter palatal barriers, many more radial
ribs (77-133), and is distinctly more elevated.
The total absence of accessory palatal traces,
simple columellar barrier, and its small size suggest
that it is a rather generalized species. The great
constriction of the umbilicus and widely spaced radial
ribbing of perahuensis are quite different from the
average pattern seen in Opanara, but do not, in
themselves, suggest affinity to another group. Ruatara
has a similarly constricted umbilicus, but markedly
different ribbing, while Orangia has the umbilicus
closed by reflection, but similar ribbing. Dissection of
the fragmentary individuals available did show a
major change within the penis (fig. 97i). Although two
pilasters are present, one occupies the upper half, the
other occupies the lower two-thirds of the penis.
Fusion of these two separate pilasters would result in
the single pilaster structure found in Ruatara (fig.
64i), or could represent another case of character
displacement. Unfortunately, the hermaphroditic duct
was not present in any example of O. perahuensis. If it
should prove to be partly coiled, as in Ruatara, then
O. perahuensis would be intermediate between Opa-
nara and Ruatara in both genital and shell structures.
Only limited material was obtained at scattered
stations on Mt. Perahu, but no species was abundant
at the particular stations.
Description of soft parts. — Foot and tail partly retracted, latter
tapered on posterior visible part, rounded behind. Sole undivided.
Pedal grooves high on foot, lower much more prominent, no caudal
horn or middorsal groove, slime network of irregular rectangles,
clearly defined.
Body color light yellow-white, no darker markings.
Mantle collar typical, no glandular extension onto pallial roof.
Pneumostome and anus normal.
Pallial region represented only by anterior portion in available
material. Lung roof with white granules bordering principal pulmo-
nary vein, densely clustered in a narrow band. Kidney, ureter, and
heart not present in available specimens. Principal pulmonary vein
unbranched until 0.5 mm. before anterior end of pallial cavity, then
splitting into five or six branches that fade out just short of mantle
edge.
Apical genitalia not available. Prostate (fig. 97h, DG) with two
rows of large acini opening into a narrow tube, only lower part seen.
Uterus (UT) bipartite, only small part of narrower upper portion
seen.
Vas deferens (VD) typical, lightly bound to penioviducal angle,
entering penis below apex to side of upper penial pilaster (fig. 97i).
Penial retractor inserts onto fleshy extension of penis head, origin
unknown. Penis (P) 2.0-2.5 mm. long, almost uniform in diameter,
with a prominent fleshy head, internally (fig. 97i) with two pilasters,
one running from apex to slightly below midpoint, other from about
one-third of way below apex to atrium. Both pilasters very slender
and low at each end, moderately to strongly elevated medially.
Atrium (Y) short and broad.
Free oviduct (UV) rather short, kinked and twisted in available
material. Spermatheca (S) shaft inserting on free oviduct slightly
above penioviducal angle. Vagina not a differentiated area.
SYSTEMATIC REVIEW
255
Right ommatophoral retractor passing through penioviducal
angle. Rest of free muscles not seen.
Jaw typical, of large rectangular plates, each plate about one-
third as wide as long.
Radula with cusps distinctly shorter than basal plates, about 5
laterals, central 10/i long and 8fj wide, outer marginals broken off and
could not be counted.
(Based on several fragmentary specimens from BPBM 142909.)
Genus Rhysoconcha, new genus
Quite small Endodontidae with very fine, but typical, apical
sculpture and microsculpture, major sculpture of moderately to very
crowded, quite narrow radial ribs. Apex and spire moderately to
strongly elevated, last whorl usually descending distinctly more
rapidly, periphery evenly rounded or slightly compressed. Whorls
about 5, tightly coiled. Umbilicus widely open (R. atanuiensis) or
secondarily constricted (R. variumbilicata). Parietal barriers 3
(atanuiensis) or 4 (variumbilicata) with 3rd, or 2nd and 4th,
respectively, recessed. Columellar barrier deeply recessed (vari-
umbilicata) or nearly reaching lip margin (atanuiensis). Palatal
barriers normally 5, rarely 6. Ovotestis with proportionately large
alveoli that lie parallel to sides of whorl and nearly fill whorl space;
hermaphroditic duct with wide collecting tubule and anterior duct,
proportionately very long. Spermatheca with narrow and elongated
head, shaft entering on penial side of penioviducal angle. Vas
deferens entering laterally on penis apex. Penis without fleshy
extension, retractor inserting directly on head, internally with two
rather closely set pilasters that are slightly higher than wide and
unite apically above vas deferens entrance. Penial retractor
originating from diaphragm. Stomach occupying one or more than
one full whorl. Central teeth of radula less than lOju long.
Type species. — Rhysoconcha variumbilicata, new
species.
Identifying features in the anatomy are the
position of the ovotestis, penial insertion of the
spermatheca, apical penial insertion of the vas defer-
ens, and absence of a fleshy head to the penis.
Conchologically the very fine sculpture and peculiarly
shaped parietal barriers (fig. 108a-b) offer a distinct
contrast to the other Rapan taxa. The size and general
shape of Rhysoconcha are quite similar to the more
widely umbilicated species of Minidonta. Prior to
dissection, I had associated the two small Rapan
species with that genus.
Dissection of the two Rhysoconcha species re-
vealed several anatomical features that contrast quite
strongly with all other dissected Endodontidae. The
follicles of the ovotestis are quite large in proportion to
the remaining genitalia and, after a short initial radial
orientation, lie parallel to the whorl sides rather than
at an angle (see Endodonta fricki, fig. 163c) as in all
other small species dissected. The collecting tube of
the hermaphroditic duct and its entrance into the
talon are both proportionately wider than usual while
the duct itself (fig. 64f, GD) is quite long in
comparison to the ducts of Orangia or Opanara. The
talon projects apicad of the albumen gland and also is
quite large. The change in spermathecal insertion,
from oviducal to penial side, is minor in distance, but
important taxonomically, since otherwise this is seen
only in the quite advanced genera Thaumatodon,
POSTERIOR
ANTERIOR
parietal-palatal
margin
POSTERIOR
ANTERIOR
ANTERIOR
FlG. 108. Structure of parietal lamellae in Rhysoconcha
variumbilicata (a, b) and Kondoconcha othnius (c, d). Greatly
enlarged. (MM).
Priceconcha, and Aaadonta (figs. 191, 195, 199, 200;
and Solem, 1973d, figs. 20-21). Nearly all Endodon-
tidae show clearly subapical insertion of the vas
deferens into the penis. Only in the specialized
Ruatara and Rhysoconcha is the insertion apical.
Possibly this indicates secondary size reduction. Ex-
cept for the last two genera, all Rapan endodontids
show a fleshy appendage to the penis head. The
pilasters in Rhysoconcha are higher than wide, unlike
those in the generalized Endodontidae and somewhat
intermediate to the very high pilasters seen in Orangia
and Opanara. Both the stomach and ovotestis have
proportionately narrower strips of digestive gland
tissue than was seen in other Endodontidae, and
apparently the stomach is longer than usual in species
of the same whorl count.
Returning to a consideration of the shell, it
became obvious that the size of the apical ribs (fig.
21a,b) were much smaller than in species of even less
diameter, such as Minidonta hendersoni (figs. 25a, c-
e), and that the size of both macro- and micro-radial
256
SOLEM: ENDODONTOID LAND SNAILS
ribs was distinctly smaller. The form of the parietal
barriers (figs. 108a-b) is quite altered from the normal
pattern seen in the Endodontidae (for example, fig.
37a).
In a group that was less conservative anatom-
ically, the differences cited above would be interesting,
but not especially significant. The concentration of so
many alterations within one pair of species in a
conservative group requires special comment. Of the
Endodontidae whose anatomy is known, Minidonta
hendersoni from Henderson Island is perhaps most
similar in size and whorl count. The poor apical
preservation of material in that species prevented
preparation of comparative drawings and measure-
ments. Direct visual comparisons of dissected parts
were made and the following comments, although not
documented by measurements, reveal significant facts.
The dissected material of Minidonta hendersoni was
subadult (diameter 1.68 mm., 4V6 whorls) in size,
although the genitalia appeared fully developed, while
the specimens of Rhysoconcha were 2.11-2.17 mm. in
diameter. Comparisons were also made with material
of Opanara areaensis.
The ovotestis alveolar clumps in Rhysoconcha
were the same size as those in Opanara, although
fewer in number, but were much, much larger and less
numerous than in Minidonta. The albumen gland
acini in Rhysoconcha and Opanara are much more
similar in size than are Rhysoconcha and Minidonta.
Similarly, the size of the collecting tubule, narrower
portion of the hermaphroditic duct and talon in
Rhysoconcha were essentially the same as in Opanara
and much, much wider than in Minidonta. Apical shell
sculpture and radial microsculpture were essentially
the same in Opanara and Minidonta, yet greatly
reduced in Rhysoconcha.
Specifically, the features of Rhysoconcha men-
tioned in the preceeding paragraphs follow the pattern
associated with secondary size reduction elucidated by
Bernhard Rensch (1966, pp. 170-177, 209-210). The
other anatomical peculiarities of Rhysoconcha out-
lined earlier can be interpreted as part of the same
pattern.
If Rhysoconcha was evolved by size reduction
from Opanara, without equal reduction in egg size, the
actual width of the alveoli in the ovotestis, collecting
tubule of the hermaphroditic duct, talon, albumen
gland acini, and free oviduct could not be decreased as
much as other organs. Hence the width of the tubes,
proportionately, would appear much greater. Space
limitations in the spire would require a reduction in
the number of ovotestis alveoli and force parallel
orientation with near filling of the whorl cross-section.
Movement of the spermathecal insertion to the penial
side would aid passage through the free oviduct.
Alterations in the penis involving size reductions
would first occur in the pilaster height. Loss of the
fleshy extension and simplification of the vas deferens
opening would save space without significant altera-
tion in function. Looking at the shell, if Opanara
sculpture was reduced in proportion to size change, the
sculpture of Rhysoconcha would be the result. The
cramped, crowded, peculiar parietal barriers of Rhyso-
concha (fig. 108a-b) bear little resemblance to the
typically formed barriers of Minidonta, but if viewed
as imperfectly reduced homologues of the Opanara
type, they make sense.
Assuming that Rhysoconcha is secondarily small
in size and evolved from the Opanara complex, then
all of the anatomical and sculptural peculiarities of
Rhysoconcha could be predicted as normal
consequences of size reduction. If Rhysoconcha is
assumed to be primitively small, then numerous
anatomical departures from a highly conservative
pattern must be explained individually. In the many
genera where size increase has been documented no
similar set of changes is seen and quite different
patterns of structural alteration are known.
The probability of Rhysoconcha representing
reduced size seems quite large. Since the Opanara and
other Rapan species are much larger than most species
of Mautodontha or Minidonta, it seems likely that the
ecological niche for a small endodontid on Rapa
probably was vacant. The opportunity for the relative-
ly infrequent phenomenon of evolution toward de-
creased size existed and Rhysoconcha was the result.
Collection of material suitable for sectioning and
detailed histological comparisons are needed to
confirm or disprove the above hypothesis. At our
present level of knowledge, its acceptance raises fewer
phylogenetic problems than its rejection.
The generic name is taken from the Greek rhysos,
meaning shrunken, and refers to the hypothesized
decreased size of the species.
Except for populations in the Maitua area,
Rhysoconcha variumbilicata and R. atanuiensis are
well-differentiated species that offer contrasting states
in 10 characters of size, shape, ribbing, and apertural
barriers (table LXXXII). On Mt. Mangaoa (Stations
485, 527) both species were collected at the same
station (fig. 109) without evidence of any inter-
gradation. Comparing the frequency distributions of
variumbilicata, atanuiensis, and the Maitua area
intermediate populations in respect to height, diame-
ter, H/D ratio, D/U ratio, rib counts, and rib spacing
(figs. 110, 111), the impression is given that blending
occurs in the Maitua area, since these populations are
essentially unimodal and almost exactly intermediate.
This is an oversimplification, since individual Maitua
populations show widely different degrees of sim-
ilarities to one or the other species. No anatomical
differences between the two species were discovered.
While breeding data obviously are lacking, the
presence of extensive character mixing in the ecolog-
ically disturbed Maitua area suggested hybridization
rather than a step cline between subspecies. Each
col col
H
I
I
O
O
O
H
§
U
~
£
2
"S S-o
CO CO
j> E.S
E 8 I
CO
To
CO
CO
<
1
t-
00
10
o
o
IO
^— .
o
t-
C0
s
PS
5
c2
o
1
o"
CD
O
o
CO
?
Q
0"
o
0
pH
X
IO
\G
CM"
CO
rH
S5
10
•^
CD
o
o
o
O
0
o
CO
^_^
^^
c-
tr-
CO
w
co
CD
o
P3
CN
CM*
co"
1
1
1
^
00
o
1 — |
ft)
t-
CO
CO
SB
O
1 1
nJ
5
r-l
o
o
co"
CO
CM*
co"
a>
CO
CO
Name
ch
blllcata
yso
arl
!
a?
CD
g
(2
OO H
^r UA
:\J .
CMl o
i i
Hi 1 U9| U3
1 ?
I i
| CO II
oj| ml
i
° 10
i
•*
0|
H
*l
1 IO
CO 1
CO I "0|
. lOl CO (M (N
<N (N CJ
1 CN
CM -t-
rH
1 (N
rH
S e
Q Q Q
IU 1U Q
if
ui ui w
J S £ S
2 to' § C
888
<0 5§
S' co r-
§. 3V
,-J _J _J
U U U
a w S os
U io u o
O OS O
Ou cu O
•^ rH CO
10
10*
TH
CO
IO ^
oo1 co x-^ ^
^ co" c?
*^s. 1 CO -V
CO rH
rH OO 1 r-
rH rH CO
03 <f
CD ll" ^? <C
CD CD CO
1 I 1
•^ 10
IO CD -^
CM IO OO
I i
"H-^ *7^ IS' "^
rH ' CO
«* CN
CM CO CO
IO *-s. IO
CO .H
rH CO IO —
" *— ' CO *— '
-* 10
IO CO IO CC
CD VO CO
OO O5
IO CD
CO rH <N IT.
O) O Ol CC
CD co 10 i/:
•^ OS OS
CO rH CO
iO IO IO
O O
o o o c
o o o
1 1
1 1 II
1 I t
CO Tp
00 CM
OO OO C- T|
CM -^ rH CS
IO IO IO -^
!^« rH IO
C- rH C*
o o
o o o c
o o" o
VO" TH'
CO t- CM C
CO CD O
CO O
C71 CD LO t—
rH CD CM
IO CD
iO IO 10 ir
K.i -tf 10
0 0
0 O O C
O O O
6T t-1
CO OO
•<*• -* IO C-
co CM t- \r.
CO *^* CM
CO V
-* •* co -^
•«t -^ -^
i i it
i I 1
o o
C» rH CO CC
CM CN! IO
CO IT-
CM CO 0 CO-
C~ OO CD
CM CM*
CO* co* co" v
CO CO CO
00 rH
* — ' * — ' ^—^ -~.
•^ CD CM C
^J" CO Ol
0> 00
c- o -^ c
CM O O>
<N CO
CO •* CO "^
•^ ^ CO
O> CO
rH CN
CO IO rH t-
c- vo TH u:
CM* CM* CM* CN
t- 0 0
IO CO CO
CM* CM CM
1 1
1 1 1
OO CO
CO O3 CO r-
CO CO OO
OO O U3 CC
c- CD c-
rH rH
oT o'
' QO cf ^ff
CO CO
CM CO 00 C
rH O> rH
rH CM
CM* Cvl" rH CN
CM* rH CM
lO CO
^ £
O X-N /— *
rH CO
1 rH
Ot Q rH i-
iH 00 S
rH 1
I a) II
1 1 1
o c-
rH C-
CO 00 CN
CD y CO t-
rH rH CO
CO C- CO
Ol" LO'
y g sr s
00 rH CO
(N* CO
CM OS
CO* y OT <>
C- ^ O> CT
V rH O
O OO iO
TH
CM CO
Tj O
CD
O CO O> U"
5! §
O CM CM
!^i CM O
rH
i 1
•a
rt a
o <n
s E
C$ M
& O
o d
1 2
1 1 1
U rt 2 c
f. 92
et
S
1 1 -
nl <tf
1 t
O| 0
3 eg •- -
"S 8 "a ^ -s •?
S -§5 i 8 i
ol c o <.
i i i
o 73 g
Q a 2S
S B S
O H
X 0
a.
10
CM o °
. . CO
cn rj- .
rH CO I/O
cu a- cu
CO O CN
257
258
SOLEM: ENDODONTOID LAND SNAILS
Rapa Island
O
•fr atanuiensis
O variumbilicata
0 hybrid
FIG. 109. Distribution of Rhysoconcha.
population sampled in the Maitua area has a relatively
small range of variation, probably reflecting both
small breeding population size and only partial genetic
mixing. There is some indication of "introgressive
hybridization" in a few populations of atanuiensis that
show some variumbilicata characters (p. 264), but field
studies are needed before any conclusions can be
reached.
The two species may be characterized as follows:
Rhysoconcha variumbilicata, new species — very
small (mean diameter 2.00 mm.), rather elevated
(mean H/D ratio 0.535), with tiny umbilicus (mean
D/U ratio 10.1), 4 parietals, a deeply recessed
columellar barrier, and rather widely spaced radial
ribs;
Rhysoconcha atanuiensis, new species — larger
(mean diameter 2.33 mm.), lower (mean H/D ratio
0.445), with wide umbilicus (mean D/U ratio 2.96), 3
parietals, columellar barrier nearly reaching lip edge,
and rather crowded radial ribs.
Variation in the two species and hybrid popu-
lations is discussed below and summarized in Tables
LXXXI, LXXXII, LXXXIII, and LXXXIV. The
specific differences in umbilical width, proportionate
height, rib count, and rib frequency are so large that
no tests of statistical significance were made. The
much more closely spaced ribs of R. atanuiensis are
clearly shown in Figure 112c. Similarly, the inter-
mediate nature of the hybrid populations is adequately
shown by the tabular data and does not require
extensive discussion.
Rhysoconcha variumbilicata, new species.
Figures 64f, g; 110-112.
Diagnosis. — Shell very small, diameter 1.74-2.37 mm. (mean
2.00 mm.), with 4'4 - 5% tightly coiled whorls. Apex and early spire
moderately to strongly elevated, usually rounded above, last whorl
descending. slightly more rapidly, H/D ratio 0.474-0.587 (mean 0.535).
Umbilicus strongly constricted internally, last whorl decoiling
slightly to moderately more rapidly, columellar wall usually concave,
contained 5.91-19.0 times (mean 10.1) in the diameter. Postnuclear
sculpture of prominent, lamellar, rather widely spaced, slightly
protractively sinuated radial ribs, 53-82 (mean 63.6) on the body
whorl, whose interstices are 4-6 times their width. Microsculpture of
fine radial riblets, six to nine between each pair of major ribs, crossed
by extremely fine and crowded spiral riblets. Sutures impressed,
whorls strongly rounded above, slightly compressed laterally on
outer margin, with flattened and inward extension of baso-
columellar margin, umbilical margin strongly rounded. Aperture
ovate, slightly compressed laterally and on baso-columellar margin,
inclined about 10° from shell axis. Parietal barriers 4, extending
posteriorly almost one-quarter whorl, 2nd and 4th deeply recessed:
upper parietal high and bladelike, expanded and serrated above on
posterior quarter, with very gradual anterior descension until just
before termination; 2nd parietal greatly reduced in height, less than
one-quarter length of upper lamella, weakly expanded and serrated
above, with sharp anterior descension; 3rd parietal nearly equal in
height posteriorly to upper, expanded and serrated above on
posterior quarter, with rather sharp descension to a raised lamellar
blade, about half the height of 1st parietal, that occupies anterior
half of barrier, with gradual anterior descension and termination
slightly beyond end of upper parietal; 4th parietal equal in height
and length to elevated portion of 3rd parietal, deeply recessed, very
short, without any anterior extension. Columellar barrier deeply
recessed, bladelike, expanded and serrated above posteriorly, with
gradual anterior descension. Major palatal barriers 5, very rarely 6 (2
per cent), short, extending posteriorly about one-eighth whorl, upper
2 reduced to short threadlike traces: lower moderately raised, very
broadly expanded above and serrated, with relatively sharp anterior
descension almost to lip margin; 2nd equal or subequal in height To
1st, somewhat less broadly expanded above, with more gradual
anterior descension; 3rd equal in height to 2nd, less broadly
expanded above, with more gradual anterior descension; 4th reduced
to a very short, deeply recessed threadlike ridge, lying below plane of
upper parietal; 5th equal in height and length to 4th, deeply recessed,
lying above plane of upper parietal; 6th, when present, located
between 2nd and 3rd major barriers.
SYSTEMATIC REVIEW
259
TABLE LXXXII. - DIFFERENCES BETWEEN RHYSOCONCHA
VARIUMBILICATA AND R. ATANUIENSIS
Mean Diameter
Mean H/D Ratio
Mean D/U Ratio
Mean Rib Count
Mean Ribs/mm.
Number of Parietals
Columellar Lamella
Upper Palatals
Lower Palatals
Body Whorl
2.00 mm.
0.535
10.1
63.5
10.38
2.33 mm.
0.445
2.96
13.53
DEEPLY
RECESSED
GREATLY
REDUCED
BROADLY
EXPANDED
ABOVE
LATERALLY
COMPRESSED
NEAR LIP
EDGE
SLIGHTLY
REDUCED
NORMALLY
EXPANDED
EVENLY
ROUNDED
The narrow umbilicus, widely spaced ribbing,
smaller size, presence of 4 parietal barriers, and higher
spire combine to separate Rhysoconcha variumbilicata
from R. atanuiensis. The other Rapan species with 4
parietals, Opanara duplicidentata, is more than twice
its size (mean diameter 4.32 mm.) and has a widely
open umbilicus (mean D/U ratio 3.03). All other
Rapan species normally have only 2 or 3 parietals.
Description. — Shell very small, with 5'/s tightly coiled whorls.
Apex and spire moderately elevated, rounded above, last whorl
descending slightly more rapidly, H/D ratio 0.574. Apical whorls 1 V
sculpture of fine radial riblets, interspersed by two or three
microradials and crossed by extremely fine spiral riblets. Postnuclear
sculpture of prominent, lamellar, widely spaced, slightly protractive-
ly sinuated radial ribs, 59 on the body whorl, whose interstices are 4-
6 times their width. Microsculpture of fine radial riblets, six to nine
between each pair of major ribs, crossed by exceedingly fine and
crowded spiral riblets. Sutures deep, whorls strongly rounded above,
slightly compressed laterally, basal margin inwardly extended and
slightly concave, columellar margin strongly rounded. Color light
yellow-white, with broad, regularly spaced, reddish flammulations
that tend to coalesce below periphery of body whorl. Umbilicus
narrow, last whorl decoiling slightly more rapidly, contained 6.78
times in the diameter. Aperture ovate, compressed laterally and on
baso-columellar margin, inclined about 10° from shell axis. Parietal
barriers 4, extending posteriorly slightly less than one-quarter whorl.
2nd and 4th shortened and very deeply recessed, with a single
accessory trace situated just below upper parietal: upper parietal
high and bladelike, expanded and serrated above on posterior
quarter, with very gradual anterior descension until just before
termination; 2nd parietal equally high and elevated, about one-
quarter length of upper parietal, without anterior extension; 3rd
parietal equal in height and length to posterior elevated portion of
upper parietal, sharply descending to a slender raised lamella, about
half the height of upper parietal, with gradual anterior descension,
terminating just beyond anterior end of upper parietal; 4th parietal
equal in height and length to elevated posterior portion of 3rd
parietal, without anterior extension. Columellar barrier a low
lamellar blade, broadly expanded above, deeply recessed within
aperture, with gradual anterior descension. Palatal barriers 5, short,
extending posteriorly about one-eighth whorl, upper 2 greatly
reduced in prominence: lower palatal high and bladelike, very
broadly expanded and serrated above with rather sharp anterior
descension; 2nd and 3rd palatals equal in height to 1st, progressively
less broadly expanded above, with more gradual anterior descension;
4th and 5th palatals shortened, greatly reduced in prominence,
situated respectively above and below level of upper parietal,
reduced to threadlike traces. Height of holotype 1.15 mm., diameter
2.06 mm.
Holotype. — Austral Islands: Rapa Island, Station
403, west slope of the northeast ridge, Mt. Mangaoa, at
800-900 ft. elevation. Collected under stones by Donald
Anderson on July 16, 1934. BPBM 144376.
Range. — Mt. Mangaoa and Maitua area at 500-
900 ft. elevation, Rapa Island, Austral Islands.
Paratypes. — Same as list of material.
Material. — Rapa Island: west slope of northeast
ridge (Stations 403, 485), Mt. Mangaoa, under stones
at 800-900 ft. elevation (90 specimens, BPBM 138337-
40, BPBM 138342, BPBM 138345, BPBM 144376-7,
BPBM 144379, BPBM 144380); northeast ridge (Sta-
tion 527) of Mt. Mangaoa under stones at 800 ft.
n 85 95 105 not
Ribs
925 1075 1225 1375 1525 1675
Rtbs/mm
FlG. 110. Frequency distribution of ribs and rib spacing in
Rhysoconcha atanuiensis, R. variumbilicata, and hybrid popu-
lations.
260
SOLEM: ENDODONTOID LAND SNAILS
Height
H/D Ratio
20r
ii
vanumbilicata
atanuiensis
mtergrade
0.86 0.92 0.99 1.05 1.12 1.18 1.25 1.32 1.38 145
mm.
Diameter
407 422 437 452 467 482 497 .512 .527 542 .557 .572 .587 .602 .61 /
5 -
D/U Ratio in logarithms
27
25
20-
•115
a
in
1.79 189 199 209 218 228 2.38 248 258 2.68
mm.
3.33 4.03 4.98 6.15 7.60 940 11.60 14.20 16.80
FIG. 111. Size and shape frequency distribution in Rhysoconcha atanuiensis, R. variumbilicata, and hybrid populations. Class intervals for
D/U ratio determined from an equal arithmetic measurement of a logarithmic scale to avoid overemphasizing degrees of narrowing above 5.50.
elevation (9 specimens, BPBM 138405-6); Maitua in
native forest with a sprinkling of coffee trees (Station
427) under stones at 575 ft. elevation (12 specimens,
BPBM 135525-8); in native forest (Station 305B)
under stones (= Station 293) (7 specimens, BPBM
137849); Maitua area (Station 304) under stones (11
specimens, BPBM 137818-8).
Remarks. -- Rhysoconcha variumbilicata has a
much more restricted distribution than does R.
atanuiensis, being known only from Mt. Mangaoa at
800-900 ft. elevation and several stations in the Maitua
area (fig. 109). On Mt. Mangaoa, both species were
collected together without sign of intergradation — at
Station 485 there were 10 atanuiensis and 56 vari-
umbilicata; at Station 527 there were one atanuiensis
and nine variumbilicata. In the Maitua area, R.
variumbilicata was collected in an ecotonal area
between the coffee plantation and native forest
SYSTEMATIC REVIEW
261
TABLE LXXXIII. - LOCAL VARIATION IN RHYSOCONCHA ATANUIENSIS,
R. VARIUMBILICATA AND HYBRID POPULATIONS
Name
variumbillcata
BPBM 138337, -8. -9
Sta. 485
BPBM 137849
Sta. 305B
BPBM 137817
Sta. 304
BPBM 135525
Sta. 427
atanuiensis-variumblllcata hybrids
BPBM 140018
Sta. 353
BPBM 137639
Sta 291A
BPBM 142536
Sta. 358
BPBM 144518, -19, -22, -23
Sta. 426
atanulensis
Number of
Specimens
20
Height
0.99*0.013
(0.89-1.09)
1.13±0.023
(1.06-1.19)
1.17±0.043
(0.99-1.39)
1.21*0.022
(1.16-1.26)
Diameter
1.88*0.020
(1.76-2.09)
2.07±0.031
(1.99-2.16)
2.16*0.054
(1.89-2.38)
2.21*0.058
(2.09-2.35)
H/D Ratio
0.526*0.0045
(0.474-0.571)
0.543*0.0089
(0.508-0.557)
0.540*0.0074
(0.523-0.583)
0.548*0.0155
(0.515-0.587)
Whorls
4 3/4*
(4 1/4-5 1/4)
4 7/8+
(4 3/4-5 1/8)
5-
(4 1/2-5 1/8)
5 1/4
(5 1/8-5 3/8)
D/U Ratio
10.88*0.749
(6.30-19.00)
10.96*0.649
(9.15-12.60)
8.29*0.916
(5.91-13.20)
9.37*0.715
(7.90-11.32)
11
18
35
BPBM 138431
Sta. 485
BPBM 142616
Sta. 435
BPBM 146161, -6, -7
Sta. 367
BPBM 144652
Sta. 474
26
0.94*0.015
(0.89-1.03)
1.95*0.023
(1.82-2.05)
0.482*0.0089
(0.436-0.525)
4 5/8-
(4 3/8-4 3/4)
3.30*0.100
(2. 95-3. 93)
1.11*0.017
(0.99-1.23)
2.20*0.020
(2.09-2.35)
0.508*0.0057
(0.476-0.570)
5-
(4 1/2-5 1/4)
4.0910.177
(3.23-6.40)
1.12*0.016
(1.09-1.16)
2.14*0.022
(2.09-2.19)
0.523*0.0085
(0.508-0.547)
5-
(4 7/8-5)
4.83*0.525
(4.20-6.40)
1.14*0.012
(1.03-1.29)
2.17*0.015
(2.02-2.35)
0.525*0.0036
(0.477-0.562)
5-
(4 1/2-5 1/4)
4.84*0.170
(2.82-6.88)
0.8610.0131
(0.82-0.89)
2.02*0. 0551
(1.88-2.11)
0. 424*0. 01031
(0.406-0.444)
45/8-1
(4 3/8-4 7/8)
2. 93*0. 060 1
(2.77-3.04)
1.02*0.032
(0.89-1.19)
2.29*0.043
(2.12-2.52)
0.444*0.0071
(0.420-0.473)
5+
(4 7/8-5 1/4)
2.74*0.053
(2.47-2.92)
1.09*0.013
(0.99-1.23)
2.42*0.016
(2.28-2.58)
0.450*0.0049
(0.412-0.500)
4 3/4+
(4 5/8-5 1/4)
3.06*0.043
(2.61-3.67)
1.15*0.025
(1.09-1.19)
2.53*0.051
(2.45-2.68)
0.455*0.0115
(0.434-0.487)
(4 3/4-5 1/4)
2.93*0.125
(2.62-3.22)
1. Subadult examples
(Station 304), in native forest with a sprinkling of
coffee trees (Station 427) and in pure native forest
(Station 305B). Typical R. atanuiensis was collected in
the coffee plantation (Station 318) and "100 yards
from the base of cliff in forest" on the northeast side of
Mt. Tautautu (Station 435). Apparently hybrid popu-
lations were taken in the coffee plantation (Stations
291A, 303, and 426), native forest (Station 305A), and
"native forest alongside and just west of marae"
(native temple) (Stations 319 and 353). There is no
simple pattern concerning the ecological distribution
of the two species and their hybrids.
Specimens of R. variumbilicata showed little
variation. One adult had a 6th palatal barrier, but
otherwise there was no apertural variation. The
constricted umbilicus with concave columellar margin
(fig. 112b) also was found in the Mangarevan Anceyo-
donta constricta (fig. 82b). Variation in rib spacing and
frequency (table LXXXIV) is minor, while the
differences between the two species are large and
obvious.
Description of soft parts. — Foot and tail about two-thirds shell
diameter in length, all material squashed laterally so that details of
foot and tail shape could not be observed. Sole undivided. Pedal
grooves quite prominent, relatively high on foot. No caudal horn or
middorsal groove. Slime network typical. Head protruding in front of
foot. Ommatophores long, light brown eyespots present. Gonopore
located below and behind right ommatophore.
Body color light yellow-white, without darker markings.
Mantle collar typical, no glandular extension onto pallial roof.
Pallial region extending somewhat more than three-quarters
whorl apically. Lung roof clear, a very few scattered granules located
near kidney. Kidney about 0.75 mm. long, very slender, somewhat
sinuated. Ureter originating below kidney anterior end, reflexing
along and terminating just anterior of rectal kidney anterior end.
Heart more than one-half length of kidney, almost parallel to
hindgut. Principal pulmonary vein typical. Hindgut following
parietal-palatal margin for one-eighth whorl above pallial cavity,
quite slender.
Ovotestis imbedded in first half whorl above stomach reflexion,
composed of four or five bi- or trifurcate long alveoli that occupy
almost entire area of whorl and parallel the plane of coiling rather
than being radiately oriented. Hermaphroditic duct (fig. 64f, GD)
rather wide above, moderately expanded and very long medially,
very abruptly reflexing into talon. Albumen gland (GG) quite small,
slender, short, individual acini not reduced in actual size. Talon (GT)
almost equal in length to albumen gland, proportionately quite large,
with expanded head and narrowed shaft. Prostate (DG) of one row,
doubled only in middle, of large acini opening into narrow duct.
Uterus (UT) typically divided into two sections.
Vas deferens (VD) a continuation of prostate duct, entering
almost apically into penis opposite point where two penial pilasters
unite. Penial retractor (PR) long, slender, originating from dia-
phragm, inserting directly onto penis head. Penis (P) about 1.50-1.95
mm. long, without fleshy head extension, tapering apically, inter-
262
SOLEM: ENDODONTOID LAND SNAILS
TABLE LXXXIV. - RIB VARIATION IN RHYSOCONCHA VARIUMBILICATA,
R. ATANUIENSIS AND HYBRID POPULATIONS
Name
variumbllicata
BPBM 144376-7
Sta. 403
BPBM 138337-8
Sta. 485
All
atanulensis-variumbillcata hybrids
BPBM 137639
Sta. 291A
BPBM 137639
Sta. 291
BPBM 144518. -23
Sta. 426
All
atanuiensis
Number of
Specimens
20
16
33
BPBM 140161
Sta. 367
BPBM 142616-7
Sta. 435
All
20
33
Ribs
60. Oil. 92
(53-67)
62.1±2.12
(56-78)
63.6
(53-82)
79. 9±2. 25
(68-104)
81.5±3.48
(73-94)
85.8±2.13
(75-96)
81.3
(68-104)
88.3±1.26
(85-93)
94.3±2.23
(79-113)
(79-132)
Ribs/mm.
9.84±0.412
(8.63-11.47)
10.36±0.368
(9.28-11.99)
10.38
(8.63-12.18)
11.83±0.324
(10.27-15.05)
11.71*0.377
(10.61-13.18)
12.22±0.309
(10.29-13.17)
11.93
(9.41-15.05)
11.66±0.253
(10.95-12.38)
13.91±0.354
(11.23-17.05)
13.53
Diameter
1.95±0.038
(1.86-2.14)
1.91±0.028
(1.81-2.07)
2.15±0.026
(1.99-2.34)
2.21±0.040
(2.07-2.34)
2.24±0.030
(2.11-2.34)
2.41±0.027
(2.32-2.47)
2.16±0.040
(1.88-2.52)
(10.95-17.05)
nally (fig. 64g) with two narrow, slender, rather closely set pilasters
that merge apically, are slightly higher than wide in the central
section and fade out basally. Atrium (Y) long and slender.
Free oviduct (UV) much longer than prostate. Spermatheca (S)
with elongated and narrow head lying hetween base of albumen
gland and apex of pallia! cavity, very slender shaft following normal
endodontid pattern, inserting on penial side of penioviducal angle.
Vagina absent.
Free muscle system typical. Right ommatophoral retractor
passing through penioviducal angle. Buccal retractors not split,
uniting posteriorly with tail fan just prior to termination of
columellar muscle. Esophagus and buccal mass typical, stomach
occupying slightly more than one whorl, intestinal looping typical,
occupying one-eighth whorl above pallial cavity. Digestive gland
reduced to single narrow strand in region of ovotestis, otherwise
typical. Salivary glands as in Endodonta.
Radula with very small teeth, centrals about 8u long and 6u
wide, laterals o or 6 in number, more than 9 marginals, but no
complete rows obtained on mounts. Jaw lost in preparation.
(Based on BPBM 138337, adult specimen 2.14 mm. in diameter
with 5' 4 whorls, five individuals dissected.)
Rhysoconcha atanuiensis, new species. Figures
110-112.
Diagnosis. — Shell quite small, diameter 1.88-2.67 mm. (mean
2.33 mm.), with 4'<s - 5'< rather tightly coiled whorls. Apex and early
spire flat to weakly elevated, last two whorls descending much more
rapidly, H/D ratio 0.406-0.500 (mean 0.445). Umbilicus broadly open,
U-shaped, whorls regularly decoiling, contained 2.47-3.67 times (mean
2.96) in the diameter. Postnuclear sculpture of narrow, prominent,
rather crowded, slightly protractively sinuated radial ribs, 79-132
(mean 93.8) on the body whorl, whose interstices are 3-4 times their
width. Microsculpture of very fine radial riblets, four to six between
each pair of major ribs, crossed by very fine and crowded spiral
riblets. Sutures impressed, strongly rounded above and on umbilical
margin, almost evenly rounded on outer margin. Aperture ovate,
almost evenly rounded on outer margin, inclined about 15° from
shell axis. Parietal barriers 3, rarely (2 per cent) 4, extending
posteriorly less than one-quarter whorl: upper parietal high and
bladelike, serrated and expanded above on posterior third, with very
gradual anterior descension until just before termination; 2nd
parietal slightly reduced in height posteriorly, expanded and serrated
portion shorter, with rather sharp descension to a raised lamellar
ridge that terminates slightly beyond anterior end of upper parietal;
3rd parietal with posterior elevated portion equal in height to 2nd
but reduced in length, rather sharply descending to an anterior
threadlike portion of varying length that terminates normally almost
one-third of length of 2nd parietal behind anterior end, but may
extend almost opposite anterior end of upper parietal. Columellar
barrier narrow, bladelike, lying almost parallel to plane of coiling,
with sharp anterior descension, almost reaching lip margin. Palatal
barriers 5, rarely 6 (4 per cent), extending posteriorly more than one-
eighth whorl: lower palatal slender, high and bladelike,
expanded and serrated above on posterior half, with abrupt anterior
descension; 2nd and 3rd palatals longer than 1st, expanded and
SYSTEMATIC: REVIEW
263
ab
H
cd
FIG. 112. a-b, Rhysoconcha variumbilicata, new species. Station 403, Mt. Mangaoa, Rapa Island, Austral Islands. Holotype. BPBM 144376;
c-d, R. atanuiensis, new species. Station 367, Atanui Bay, Rapa Island, Austral Islands. Holotype. BPBM 140161. Scale lines equal 1 mm.
Drawings by YK reproduced through the courtesy of Bernice P. Bishop Museum.
serrated above on posterior half, with progressively more gradual
anterior descension; 4th and 5th palatals markedly reduced in height,
low lamellar blades, slightly recessed, with very gradual anterior
descension; 6th palatal, when present, located between 2nd and 3rd.
The wide umbilicus, much more crowded ribbing,
lower spire, presence of 3 parietals, close approach of
the columellar barrier to the lip edge, and much larger
size of the upper 2 palatals combine to immediately
separate specimens of Rhysoconcha atanuiensis from
R. variumbilicata. All other Rapan species are consid-
erably larger, mean diameter at least 2.82 mm., and
usually have only 4 palatal barriers.
Description. — Shell quite small, with 5' 4 rather tightly coiled
whorls. Apex and early spire flat, last two whorls descending
progressively more rapidly, H/D ratio 0.494. Apical whorls I1*, with
sculpture of strongly retractive radial rihlets, interspersed by one or
two microradials and crossed by tiny microspiral riblets. Postnuclear
whorls with low, prominent, rather crowded, slightly protractively
sinuated radial ribs, 98 on the body whorl, whose interstices are 3-4
times their width. Microsculpture of extremely fine radial riblets.
four to six between each pair of major ribs, with a distinctly finer
and more crowded sculpture of spiral riblets. Sutures deep, whorls
strongly rounded above and on umbilical margin, almost evenly
rounded on outer margin. Apex and spire light yellow-white, lower
whorls with broad and irregular, reddish flammulations thaf tend to
coalesce near periphery and on shell base. Umbilicus broadly open,
U-shaped, regularly decoiling, contained 3.12 times in the diameter.
Aperture ovate, evenly rounded on outer margins, inclined less than
15° from shell axis. Parietal barriers 3, extending posteriorly almost
one-quarter whorl: upper parietal high, thin, bladelike, expanded and
serrated above on posterior third, with very gradual anterior
descension until just before termination; 2nd parietal equally high
posteriorly with expanded portion slightly shorter and sharply
descending to a lower bladelike portion that extends anteriorly
slightly beyond end of upper parietal; 3rd parietal with posterior
elevated portion slightly lower and shorter than 2nd parietal, deeply
recessed, with anterior margin 0.36 mm. behind edge of 2nd parietal.
Columellar barrier a thin bladelike lamella, extending quite far
posteriorly (fig. 112c), almost parallel to plane of coiling, stopping
just short of lip margin. Palatal barriers 5, short and high, extending
about one-eighth whorl: lower parietal thin, narrowly expanded and
serrated above on posterior half, with abrupt anterior descension;
264
SOLEM: ENDODONTOID LAND SNAILS
2nd and 3rd palatals equal in height to 1st, slightly longer, expanded
and serrated above on posterior half, with progressively more gradual
anterior descension; 4th palatal markedly reduced in height, but still
low and bladelike, expanded and serrated above, with very gradual
anterior descension, lying below plane of upper parietal; 5th palatal
similar in shape to 4th, more deeply recessed, reduced in height, lying
above plane of upper parietal. Height of holotype 1.22 mm., diameter
2.46 mm.
Holotype. — Austral Islands: Rapa Island, Station
367, hillside on south end of Atanui Bay at 300-400 ft.
elevation. Collected under stones in a coffee plantation
by Donald Anderson on July 12, 1934. BPBM 140161.
Range. — Widely dispersed at low to intermediate
elevations, with higher records on Mt. Mangaoa and
Mt. Perahu, Rapa Island, Austral Islands.
Paratypes. — Same as list of material.
Material. — Rapa Island: Tapui Islet (Station
442) at 20 ft. elevation on dead kukui twigs and leaves
(1 specimen, BPBM 142681); hillside at Pake Bay
(Station 321) (1 specimen, BPBM 137971); Titikaveka
Valley (Station 414) at 500 ft. elevation (1 specimen,
BPBM 140558); above cemetery at Ahurei (Station
504) (1 specimen, BPBM 143658); northwest of Mt.
Tepiahu (Station 330) at 500-600 ft. elevation under
stones in a forest with coffee trees predominating (4
specimens, BPBM 138072-4); hillside on south side of
Atanui Bay (Station 367) at 300-400 ft. elevation
under stones in a coffee plantation (62 specimens,
BPBM 140161-8); hillside above Area (Stations 383,
474) at 250-450 ft. elevation under stones and on dead
leaves (6 specimens, BPBM 140508, BPBM 144652-3);
hillside and valley west of Tavaitahu (Stations 346,
347) at 750 ft. elevation under stones in forest (10
specimens, BPBM 142471, BPBM 142183, BPBM
142502-4); valley northwest of Mt. Tautautu (Station
342) at 600-700 ft. elevation under stones (4 specimens,
BPBM 142406); hillside northeast of Mt. Tautautu,
east Maitua area (Station 435) under stones and on
dead leaves (33 specimens, BPBM 142616-9); hillside
back of Maitua (Station 318) under stones and in
moist wood in a coffee plantation (10 specimens,
BPBM 144084-6); northeast ridge of Mt. Mangaoa
(Stations 485, 526, 527) at 800-1,100 ft. elevation under
stones and on dead leaves (12 specimens, BPBM
138341, BPBM 138343, BPBM 138408, BPBM 143740);
southeast valley of Mt. Orangi hillside (Stations 296,
299) at 550-700 ft. elevation (14 specimens, BPBM
137783, BPBM 138486-7); east ridge of Mt. Perahu
(Stations 453, 512) at 1,500-1,900 ft. elevation (3
specimens, ex BPBM 135483, ex BPBM 135485, BPBM
142905).
Remarks. - The appearance of typical Rhyso-
concha atanuiensis has been outlined above. Popu-
lations from Atanui, Area, and Mt. Orangi do not
deviate from the basic pattern. Others show some
characters typical of R. variumbilicata. One set from
the Maitua area (Station 435, BPBM 142616-9) has
the columellar barrier deeply recessed and the upper
two palatals reduced to traces, but the shape (table
LXXXIII) and ribbing (table LXXXIV) of typical
atanuiensis. In size (tables LXXXI, LXXXII), this
population is intermediate between the two forms. The
single shells from Ahurei and Pake Bay, plus some of
the Tavaitahu and the four Mt. Tepiahu examples
have a very weak 4th parietal located between the 1st
and 2nd. All of the above, plus two of the three Mt.
Perahu shells, and some of the Mangaoa and Maitua
specimens have the columellar barrier deeply recessed.
All of the above have the shape, size, and ribbing of
atanuiensis.
Most R. atanuiensis were taken at 250-700 ft.
elevation, but some individuals were taken on Mt.
Mangaoa at 800-1,100 ft. and Mt. Perahu at 1,500-1,900
ft. elevation. Two individuals had a 6th palatal located
between the 2nd and 3rd palatals. Otherwise barrier
variation included only characters tending toward the
variumbilicata condition.
Description of soft parts. — Foot and much of head region in all
available material had been pulled off during original field
processing, with only tip of tail remaining. Sole undivided, pedal
grooves high on side of foot, tail slightly tapering and rounded
posteriorly.
Body color yellow-white, without darker markings.
Pallial region extending five-eighths to three-quarters whorls
apically. Lung roof clear, no trace of granulations. Kidney very
narrow, about 0.90 mm. long, sinuated, rectal arm about one-third
length of pericardial. Ureter typical. Heart over one-half length of
kidney, nearly parallel to hindgut, very large in proportion to kidney
size. Principal pulmonary vein very inconspicuous. Hindgut typical,
following parietal-palatal margin well above pallial cavity apex.
Ovotestis imbedded in first half to three-quarters whorl above
stomach reflexion, lying parallel to sides of whorl rather than being
radiatelv oriented, nearly filling whorl, composed of four to five bi-
or trifurcate long alveoli. Hermaphroditic duct slender, medially
expanded, sharply reflexed before entering talon shaft, proportion-
ately much longer than usual. Albumen gland very narrow, small,
scarcely longer than talon, acini as large as in normal species. Talon
typical in shape and form, proportionately very large. Prostate
mainly with one row of acini, doubled in middle, opening into slender
duct. Uterus typical.
Vas deferens typical, reflexing at penioviducal angle, entering
apically into penis on opposite side from pilaster union. Penial
retractor arising from diaphragm, inserting directly onto penis head
without fleshy extension, relatively long. Penis about 1.6-1.9 mm.
long, tapering apically, internally with two narrow, rather closely set
pilasters, medially slightly higher than wide, merging at penis apex,
decreasing in prominence near end of broken specimens. Lower part
of penis, spermatheca, free oviduct and all of atrium missing in
available material. Spermatheca with narrow and elongated head
lying between apex of pallial cavity and base of albumen gland,
remaining part of shaft in normal position.
Stomach, esophagus and intestinal coiling as in R. vari-
umbilicata.
Radula with very small teeth, centrals about 8-10/i long, 6ji wide.
Mounted individuals with 6 laterals, 11 marginals with edge turned
under slightly. Jaw lost in processing.
(Based on BPBM 142616, adult specimens 2.11 and 2.17 mm. in
diameter with, respectively, 4%- and 4% whorls. Six examples
dissected at least in part.)
Rhysoconcha atanuiensis-variumbilicata hybrids.
Figures 110, 111.
Material. — Rapa Island: Maitua, in a coffee
plantation (Stations 291A, 303, 426) at 500-600 ft.
SYSTEMATIC REVIEW
265
elevation under stones (81 specimens, BPBM 135796,
BPBM 137639-40, BPBM 144518-23); Maitua, in
native forest (Station 305A) at 700 ft. elevation near
cliff (15 specimens, BPBM 137838-42); Maitua, unlo-
calized area (Station 358) at 550 ft. elevation (9
specimens, BPBM 135701, BPBM 142536); Maitua, in
native forest alongside and just west of marae (native
temple) (Stations 319, 353) at 750 ft. elevation (26
specimens, BPBM 138534, BPBM 140018-20.)
Remarks. — In the Maitua area of Rapa there is a
complex of populations that shows various types of
intergradation between R. atanuiensis and R. vari-
umbilicata. Each of the Maitua populations shows a
relatively stable umbilical form (table LXXXIII), but
populations that apparently are less than 200 ft. apart
can differ widely in umbilical size and ribbing. Ten
stations of the Mangarevan Expedition were located
from the coffee plantation up to the base of the cliff at
Maitua. It is difficult to determine the precise
geographic relationship of the stations, but they are
apparently placed approximately as indicated below.
Stations 291, 303, and 426 are all designated as
specifically within the coffee plantation at about 500-
600 ft. elevation. Eighteen adults from Station 291A
(BPBM 137639) had the D/U ratio varying from 3.23-
6.40 (mean 4.09). A single juvenile shell from Station
303 (BPBM 135796) had the umbilicus within the
same size range. A larger series of shells from Station
426 (BPBM 144518-23) had the D/U ratio varying
from 2.82-6.88 (mean 4.84). Station 427 (BPBM 135525,
135527) is stated as being located about 50 yd. south of
Station 292 which is located 100 yd. above and about
75 ft. higher in elevation than Station 291. Stations
292 and 427 were located in essentially native forest
with a sprinkling of coffee trees. The four adults of
variumbilicata from Station 427 had a D/U ratio from
7.90-11.32 (mean 9.37). Station 305B (BPBM 137849) is
the same as Station 293, which is located above
Station 292 and about 100 yd. below the cliff in native
forest. The five adults of variumbilicata from Station
305B had a D/U ratio of 9.15-12.60 (mean 10.96).
Station 305A (BPBM 137838-42) is located just above
Stations 305B and 293. The two adults from Station
305A have D/U ratios of 4.33 and 6.19. Station 304
(BPBM 137817) is stated to lie on the hillside between
Stations 291 and 293 and the collection was made
under a single pile of stones. The D/U ratio of eight
variumbilicata adults ranges from 5.91-13.20 (mean
8.29). Presumably Station 304 is ecologically equiva-
lent to Station 292; i.e., being located on the ecotonal
area between the coffee plantation and the native
forest. Station 319 (BPBM 138534) is at 750 ft.
elevation, about 20 ft. west of the marae (native
temple) in moist native forest. The two adults have a
D/U ratio of 2.86 and 3.39. Shells from Station 353
(BPBM 140018-20) are from essentially the same
population as the material from Station 319, since the
locality is given as "alongside of Marae which is just
below Mangaoa (a little to the west)." The 11 adult
shells had a D/U ratio of 2.95-3.93 (mean 3.30).
Specimens from Station 358 (BPBM 142536), an
unlocalized place at Maitua (elevation 550 ft.), have a
D/U ratio of 4.20-6.40 (mean 4.83).
As indicated above, R. variumbilicata was collect-
ed at Stations 304, 305B, and 427. The remaining
stations had specimens that were intermediate in
different ways. The specimens from Stations 319 and
353 were more similar to atanuiensis in shape
(mean H/D ratio 0.478) and umbilical width (mean
D/U ratio 3.27), although with the size (mean height
0.94 mm., mean diameter 1.96 mm.) of variumbilicata
and almost precisely intermediate in rib count (mean
76.0) and rib spacing (mean ribs/mm. 12.10). All
checked specimens had 4 parietals, the 2 upper palatals
reduced to threads, but the columellar barrier recessed
in some, reaching the lip edge in others.
Specimens from Stations 291A, 303, 305A, 358, and
426 were similar to atanuiensis in shape (mean H/D
ratio 0.522), intermediate in size (mean diameter 2.16
mm.), umbilical width (mean D/U ratio 4.63), rib
count (mean ribs 82.7), and rib spacing (mean
ribs/mm. 11.96). From Stations 291 and 426, in the
checked examples, there were 12 with 3 parietals and
24 with 4 parietals; 15 had the columellar barrier
reaching the lip edge, while in 21 examples it was
deeply recessed; and all had the 2 upper palatals
reduced to threads.
Providing the more than 40 years since the
Mangarevan Expedition collections have not seen
destruction of these populations, the Maitua area
offers what may be a unique opportunity to study
snail evolution in action. Efforts by Harald Rehder to
collect material in this area were unsuccessful in the
last few years and I am not optimistic concerning their
survival (see p. 100).
Genus Ruatara, new genus
Endodontidae having typical apical and microsculpture, major
radial sculpture normally spaced or rather crowded. Apex and spire
slightly to moderately elevated, sometimes rounded above, body
whorl descending only slightly more rapidly, periphery rounded or
obtusely angulated. Whorls about 5'/2, rather tightly coiled, number
reduced in Ruatara koarana, greatly reduced in Ruatara oparica
oparica. Umbilicus barely perforate to closed in both juveniles and
adults, columellar wall essentially parallel to shell axis. Parietal
barriers usually 2 or 3, rarely more, prominent, greatly shifted in R.
koarana. Columellar barrier twisted onto basal lip (R. koarana)',
prominent and deeply recessed; or slanting partway across colu-
mellar callus. Palatal barriers 0-5, usually 3 or 4, reduced to absent
in R. oparica reductidenta. Hermaphroditic duct highly convoluted.
Penis with near apical insertion of vas deferens and without fleshy
extension to penis head, internally with one very large and
transversely rugose pilaster. Spermatheca and free oviduct uniting
well above atrium, producing a clearly marked vaginal region.
Anatomy otherwise typical of the Endodontidae.
Type species. — Ruatara oparica normalis, new
subspecies.
The convolution of the hermaphroditic duct,
presence of only one rugose pilaster in the penis, clear
266
SOLEM: ENDODONTOID LAND SNAILS
acd
FIG. 113. a-b, Ruatara koarana, new species. Station 357, Mt. Koara, Rapa Island, Austral Islands. Holotype. BPBM 142521; c-d, R.
oparica oparica (Anton). Opana ( = Opara, Rapa) Island. Probably paratype. FMNH 46378 ex W. F. Webb, Gerard Gude. Scale lines equal 1
mm. Figures a-b by YK reproduced through the courtesy of Bernice P. Bishop Museum; c-d (MM).
demarcation of a vaginal region, near apical penial
insertion of the vas, and absence of an umbilical
opening in juvenile shells combine to separate Ruatara
from the other Rapan genera. Anatomically, it is one
of the most clearly differentiated Eastern Polynesian
genera. The first three characters separate it from all
other genera in the family.
Inclusion of Ruatara koarana is based on general
conchological similarities, since no anatomical material
of that species suitable for dissection was available.
Quite possibly it is an aberrant Opanara, but until
dissected, it can be classified here. The great alteration
of the columellar region in R. koarana, resulting in
staggered recession of the parietal barriers (fig. 113b),
is unique among the known Endodontidae, as is the
change in position of the columellar barrier from
parallel to the plane of coiling in juveniles, to deflected
onto the basal lip in adults. While the apertural
barriers are much larger than those found in R.
oparica, the character of the sculpture and general
shell shape are more similar to that species than to
any other Rapan taxon.
Ruatara oparica is widely distributed on Rapa
and has been divided into three subspecies. R. koarana
has been found only at a single station on Mt. Koara.
The two species are readily separable by characters of
the parietal barriers. The following comparison substi-
tutes for a formal key:
Ruatara koarana — parietal barriers strongly and
progressively more deeply recessed within aperture;
Ruatara oparica — parietal barriers with at least
2nd terminating slightly in front of anterior end of
upper parietal.
Ruatara koarana, new species. Figure 113a-b.
Diagnosis. - Shell small, diameter 2.80-3.03 (mean 2.93 mm.),
with 4:)4 - 5V2 rather tightly coiled whorls. Apex and spire slightly and
almost evenly elevated, a trifle rounded above, last whorl descending
a little more rapidly, H/D ratio 0.567-0.670 (mean 0.612). Umbilicus
barely perforate to closed. Postnuclear sculpture of narrow,
prominent, lamellar, protractive radial ribs, 79-81 (mean 80) on the
body whorl, whose interstices are 2-3 times their width. Micro-
sculpture of fine radial riblets, three to six between each pair of
major ribs, crossed by extremely fine and crowded spiral riblets.
SYSTEMATIC REVIEW
267
Sutures impressed, whorls flatly rounded down to obtusely angulated
periphery, with evenly rounded lower palatal and basal margin.
Aperture ovate, slightly flattened laterally above obtusely angulated
periphery, inclined about 20° from shell axis. Parietal barriers 3, high
and bladelike, irregularly situated within aperture: upper very high
and bladelike, weakly expanded and serrated above on posterior half,
rather sharply descending to anterior end; 2nd parietal set back
almost three-sixteenths of a whorl from anterior end of 1st, equally
high and expanded posteriorly, with more gradual anterior descen-
sion to a short and threadlike segment that terminates well behind
anterior end of upper parietal; 3rd parietal recessed almost one-
quarter whorl from anterior end of upper, visible portion equally
high, with very sharp anterior descension, entire barrier strongly
twisted from plane of coiling. Columellar barrier a high bladelike
ridge, lying almost perpendicular to shell axis in juveniles, twisted
downward onto basal lip in adults and almost touching lower
palatal barrier. Palatal barriers 4, very high, extending posteriorly
about one-eighth whorl: lower palatal markedly displaced from
normal position by deflection of columellar, not lying parallel to
plane of other palatals, deeply recessed, with sharp anterior
descension to middle of baso-columellar callus; 2nd palatal slightly
displaced from normal position, more strongly expanded and serrated
above, less deeply recessed, with more gradual anterior descension;
3rd palatal nearly normal in position, slightly lower than 2nd, with
even more gradual anterior descension; 4th palatal peripheral, deeply
recessed, greatly reduced in height, a crescentic or V-shaped ridge
situated slightly above level of upper parietal.
The extreme recession of the lower parietals
coupled with displacement of the columellar and lower
palatal barriers is unique in the Endodontidae. Of the
other Rapan species, it is most likely to be confused
with R. oparica oparica, which has much more
crowded ribbing and the columellar barrier on the
columellar lip. Opanara perahuensis has regularly
spaced parietals, a much different ribbing pattern and
more whorls. Other Rapan species with narrow or
closed umbilici have only 2 parietals.
Description. — Shell small, with 5 rather tightly coiled whorls.
Apex and spire slightly and evenly elevated, last whorl descending a
trifle more rapidly. H/D ratio 0.567. Embryonic whorls 1"2, sculpture
eroded. Postnuclear whorls with narrow, crowded, lamellar, pro-
tractive radial ribs, 81 on the body whorl, whose interstices are 3-
4 times their width. Microsculpture of fine radial riblets, three to
six between each pair of major ribs, crossed by exceedingly fine and
crowded spiral riblets. Sutures shallow, whorls flatly rounded down
to very weakly and obtusely angulated periphery, lower palatal
margin evenly rounded, becoming slightly flattened basally. Color
light yellow horn with irregular, zigzagged, reddish flammulations.
Umbilicus minutely perforate, contained 45 times in the diameter.
Columellar wall with exceedingly thick and extensive callus,
extending well on to basal margin. Aperture ovate, slightly flattened
laterally above periphery, with evenly rounded lower palatal margin,
basal margin somewhat sinuated. Parietal barriers 3, very high and
thin, irregularly situated within aperture: upper parietal extending
slightly more than one-quarter whorl, expanded and serrated above
on posterior visible half, with gradual anterior descension; 2nd
parietal deeply recessed, posteriorly equal in height to upper parietal,
elevated portion twisted diagonally downward from front to rear,
with slightly sharper anterior descension to a threadlike portion that
stops just anterior of upper parietal end; 3rd parietal set back almost
one-quarter whorl, equally high posteriorly, twisted diagonally
downward from plane of coiling, without threadlike anterior portion.
Columellar barrier a moderately elevated bladelike ridge, deflected
downward onto basal margin, deeply recessed within aperture,
reaching slightly past apex of heavy basal columellar callus, with its
anterior end almost touching side of 1st palatal. Palatal barriers 4,
short, very high, displaced from normal position: 1st palatal high and
bladelike, weakly expanded posteriorly, with sharp anterior descen-
sion to middle of callus, less recessed, less deflected from plane of
coiling, with more gradual anterior descension; 3rd palatal equal in
height to 2nd. situated slightly below level of upper parietal, with
more gradual anterior descension; 4th palatal peripheral in position,
greatly reduced in height, an elevated, weakly crescentic ridge,
deeply recessed within aperture and situated above level of upper
parietal. Height of holotype 1.68 mm., diameter 2.96 mm.
Holotype. — Austral Islands: Rapa, Station 357,
Oromange, Mt. Koara at 800 ft. elevation on a hillside
under stones in native forest. Collected by Harold St.
John on July 11, 1934. BPBM 142521.
Range. — Only known from near Oromange, Mt.
Koara at 800 ft. elevation, Rapa Island, Austral
Islands.
Paratypes. — Same as list of material.
Material. — Rapa Island: Mt. Koara (Station 357)
near Oromange at 800 ft. elevation (4 specimens,
BPBM 142521-2).
Remarks. — Only four specimens of this remark-
able shell were found. The single juvenile, 2.10 mm. in
diameter with 3% whorls, has a slightly open umbilicus
and the columellar barrier is perpendicular to the shell
axis. In the adult specimens, the columellar twists
down and occupies a basal position, roughly paralleling
the lower palatal. The extreme development of the
baso-columellar callus and consequent gross dis-
placement of the 2 lower parietals, the columellar and
first 2 palatal barriers are unique. Even in the juvenile
shell, the deep recession of the lower parietals, and the
sideways twisting of the lower palatal barriers is
evident. Unfortunately, it was impossible to dissect
this species and reference of it to Ruatara much be
considered tentative.
The crowding of the radial ribs, mean ribs/ mm. is
8.91, is slightly greater than in the much larger R.
oparica normalis and much, much less than in R. o.
oparica, which is essentially identical in height,
although much more depressed.
Ruatara oparica (Anton, 1839)
Ruatara oparica is the only species of endodontid
previously known from Rapa, and the second most
frequently encountered species collected by the Man-
garevan Expedition. It shows considerable variation in
apertural barriers, ribbing and umbilical opening. As
with most other species for which very large samples
were available, the following analysis is based on only
part of the material. Time did not permit measuring
all specimens. Recognition of three subspecies, R.
oparica oparica, R. o. normalis, and R. oparica
reductidenta, is conservative. Division into four sub-
species is logically defensible, but would not be
consistent with taxonomic treatment elsewhere in this
study.
Barrier variation concerns both actual numbers
and relative prominence. Considering all specimens
studied, the number of parietals varied from 1 - 5, but
only 8 (2 per cent of 402 examples checked) had 1 or 5;
35 (8.7 per cent) had 4; 99 (24.6 per cent) had 2; and
FIG. 114. a-d, Ruatara oparica normalis, new subspecies, a-b, form with 3 parietals, Morongoto, Rapa Island, Austral Islands. BPBM
53246; c, form with 2 parietals. Station 490, Mt. Ruatara, Rapa Island, Austral Islands. Paratype. BPBM 143492; d, form with prominent
barriers. Station 360, Morongoto, Rapa Island, Austral Islands. Paratype. BPBM 144246; e, R. o. reductidenta, new subspecies. Station
291, Maitua, Rapa Island, Austral Islands. Holotype. BPBM 137609. Scale lines equal 1 mm. Drawings by YK reproduced through the
courtesy of Bernice P. Bishop Museum.
268
SYSTEMATIC REVIEW
269
259 (64.7 per cent) had 3 parietals. Specimens from the
northern part of Rapa (Mt. Perahu and Mt. Ruatara)
usually have only 2 parietals, while those from the
southern part of the island generally have 3 parietals
(fig. 115). Using the contingency table comparison, this
difference is highly significant (x2 = 8.69). Visual
inspection of Figure 115 indicates that there is no
difference in parietal barrier frequency distributions
between both oparica oparica and oparica normalis
from the southern part of Rapa and oparica reducti-
denta from the Mt. Tautautu region.
Palatal barrier counts are equally variable, the
number ranging from 0-5, with considerably different
frequencies observed. Specimens from the Mt. Tau-
tautu-Maitua area (reductidenta) normally lack all
palatals. Even though one or two palatal traces are
often present (16 per cent), they are reduced in size to
tubercular nodules and are in no sense truly
comparable to the large 1st and 2nd palatals seen in R.
oparica oparica. Hence Figure 115 tends to mask the
gross differences between the Mt. Tautautu-Maitua
populations and those from other areas by failing to
reflect the size difference in the 1st and 2nd palatals.
Although there seems to be a difference in proportions
between the north Rapan populations and the non-Mt.
Tautautu south Rapan populations in the frequency
of 3 and 4 palatals (fig. 115), the difference does not
reach a significant level (\2 = 2.56). Further study of
the north Rapan material may show that a significant
difference exists. Numerical reduction in the palatals
was, without exception, orderly, the upper being lost
before the 3rd, 3rd before the 2nd, etc.
Rib variation was equally complicated. The type
material, all specimens in old collections, and the few
examples from Station 466 on the south side of Mt.
Tanga at 700-800 ft. elevation agreed in having a large
number of very crowded ribs (tables LXXXI and
LXXXV). Specimens from the Mt. Tautautu-Maitua
area had relatively few, much less crowded ribs, while
the remaining specimens taken by the Mangarevan
Expedition were approximately intermediate in rib
count (table LXXXVI), but tending closer to the Mt.
Tautautu-Maitua type in rib frequency (table
LXXXVII). Specimens taken from Mt. Ruatara
(Station 491) and south Rapa (exclusive of the
reductidenta and oparica populations) were virtually
identical in ribbing and rib frequency, since the means
for all normalis taken by the Mangarevan Expedition
(table LXXXI) and those from Station 491 (table
LXXXVI) are essentially the same. Differences in rib
count and ribs/ mm. between normalis and reducti-
denta are highly significant, with 53 df, "t" = 8.469 for
rib count and "t" = 6.481 for ribs/mm. The differences
between reductidenta and the nominate race are so
large that no test of statistical significance was
necessary.
Umbilical closure is most advanced in R. o.
reductidenta, with only 1 of 93 examples having a
TABLE LXXXV. - FREQUENCY DISTRIBUTION OF RIBS /MM. IN RUATARA OPARICA
Ribs/mm.
5.71-6.70
6.71-7.70
7.71-8.70
8.71-9.70
9.71-10.70
10.71-11.70
11.71 12.70
12.71-13.70
13.71 14.70
14.71
Number
Mean
Range
oparica
oparica
1
7
2
3
2
15
12.96
(10.75-14.83)
oparica
normalis
3
13
20
13
1
1
51
8.12
(6.01 -10.83)
reductidenta
12
16
1
29
6.85
(5.71-8.04)
North Rapa
oparica
South Rapa
oparica
oparica
reductidenta
yu-
80-
6<
i
70-
OJ
f 60-
CO
50-
o
1 40"
1 30-
20-
14
10-
3
o-l
2 3 4
2345
Number of Parietals
12345
ro
o>
cj
90-
80-
70-
60-
50-
40-
30-
20-
10-
0-
157
34 01234
Number of Palatals
FIG. 115. Parietal and palatal barrier number variation in Ruatara oparica.
29
0 1 2
270
SYSTEMATIC REVIEW
TABLE LXXXVI. - RIB VARIATION IN RUATARA OPARICA
271
Form
oparica
Cuming
norm alls
Sta.491
reductidenta
Sta. 291
Number of
Specimens
13
30
25
Rib Count
119.8±3.60
(101-150)
99.8±1.86
(77-121)
78.4±1.64
(66-93)
perforate umbilicus. It is least advanced in R. o.
oparica, with only 5 of 24 having a closed umbilicus.
R. oparica normalis is intermediate, with 72 specimens
having a perforated umbilicus and 82 a closed
umbilicus. When open, the umbilicus still was so
minute that no meaningful measurements were
possible.
The importance of local size variation (table
LXXXVII) cannot be determined from present data.
This was one of the first species measured and
inclusion of some paraneanic individuals in smaller
sets and presence of essentially only gerontic individ-
uals in other sets (Station 490, table LXXXVII)
certainly biased measurements, particularly in respect
to height and diameter. The much greater size of the
specimens from Station 490 almost certainly is the
result of sample bias. On the other hand, the small size
of individuals from Station 399 may have biological
significance. These shells were collected from a ridge
on open ground under dead leaves. The habitat would
be much drier than from a forest with a greater degree
of moisture retention and a local "dwarfing" effect
would be a reasonable expectation. Whether the lower
H/D ratio of Station 399 examples is correlated with
the small size (compare with the H/D ratios of R.
oparica oparica) or reflects a genetically caused
lowering of the spire is unknown. Similarly, I have no
explanation concerning the greater H/D ratio of the
few Mt. Perahu examples.
When the variations discussed above are corre-
lated, a division into three subspecies seems most
reasonable:
Ruatara oparica oparica (Anton, 1839) from Mt.
Tanga is quite small with very numerous and crowded
radial ribs, apertural barriers as in the south Rapan
populations of R. o. normalis;
Ruatara oparica normalis, new subspecies from
north Rapa and most of south Rapa (except Mt.
Tanga, Maitua and Mt. Tautautu) is rather large with
fewer and more widely spaced radial ribs, generally
(73.6 per cent) with 4 palatals and most frequently
with 3 parietals on south Rapa and 2 parietals on
north Rapa.
Ribs/mm.
12.73±0.304
(10.75-14.83)
,22±0.167
(6.01-9.76)
6.93±0.085
(6.33-8.04)
Diameter
2.99±0.052
(2.80-3.39)
3.88±0.055
(3.22-4.44)
3.59±0.046
(3.26-4.08)
Ruatara oparica reductidenta, new subspecies
from Maitua and Mt. Tautautu is insignificantly
smaller than R. oparica normalis and has fewer and
more widely spaced radial ribs, but differs most
significantly in having normally no palatal barriers;
even when 1 or 2 are present, they are reduced to
extremely small tubercular nodules.
Within R. oparica normalis there is the north-
south dichotomy in parietal barrier frequency, but
since the populations agree in all other respects, I
attach no systematic recognition to this variation. The
three subspecies are geographically isolated (fig. 116)
and readily separable on a population basis. Although
the loss of palatal barriers that distinguished R. o.
reductidenta is a more dramatic alteration, there is a
greater amount of change required in altering either of
the other two subspecies into R. oparica oparica.
Ruatara oparica oparica (Anton, 1839). Figures
113c, d; 115; 116.
Helix (Helicodonta) opanica (sic) Anton, 1839, Verzeich. d.
Conchol., p. 39, no. 1443 — "Opana in Amerika" (error).
Helix oparica Anton, Pfeiffer, 1842, Sym. Hist. Helic., 2, p. 92 -
Rapa (= Opara) Island (necessary emendation); Pfeiffer, 1848,
Monog. Helic. viv., 1, p. 186; Deshayes. 1850, Hist. Nat. Moll.
terr. f'luv., 1, p. 191, no. 257, pi. 55, fig. 12 (plate issued in 1841);
Pfeiffer, 1852, Syst. Conchyl. Cab., I, 12, (2), p. 199, pi. 100, figs.
16-20 (plate issued in 1&50); Pfeiffer, 1853, Monog. helic. viv., 3,
p. 144; Pfeiffer, 1868, Ibid., 5, p. 221; Pfeiffer, 1876, Ibid., 7, p.
259.
Helix (Endodonta) oparica (Anton), Tryon, 1887, Man. Conchol.,
(2), 3, p. 67, pi. 12, figs. 37-39 (copied from Syst. Conchyl. Cab.).
Endodonta (Thaumatodon) opanica (sic) (Anton), Pilsbry, 1893,
Man. Conchol.. (2). 9, p. 26.
Diagnosis. — Shell quite small, diameter 2.80-3.39 mm. (mean
2.98 mm.), with 4'/4 - 5'4 normally coiled whorls. Apex and spire
moderately and evenly elevated, very slightly rounded above, last
whorl descending a trifle more rapidly, H/D ratio 0.488-0.597 (mean
0.565). Umbilicus usually minutely perforate, too narrow to measure,
frequently (20.8 per cent) closed. Postnuclear sculpture of narrow,
lamellar, crowded, protractively sinuated radial ribs, 101-154 (mean
122.9) on the body whorl, whose interstices are less than twice their
width. Microsculpture of fine radial riblets, two to three between
each pair of major ribs, crossed by barely visible and extremely
crowded spiral riblets. Sutures impressed, whorls strongly rounded
above and on outer margin, with basal margin slightly flattened and
extended inwardly. Aperture ovate, with strongly rounded margins,
inclined about 15° from shell axis. Parietal barriers variable in
272
SOLEM: ENDODONTOID LAND SNAILS
TABLE LXXXVII. - LOCAL VARIATION IN RUATARA OPARICA
Name
oparica oparica
British Museum
BPBM 143113
Sta. 466
oparica normalis
BPBM 140385, -7
Sta. 399
BPBM 142936
Sta. 455
BPBM 138402, -4
Sta. 527
BPBM 143747, -9
Sta. 526
Mt. Perahu
Sta. 376, 446, 451-2,
509, 512-3
BPBM 144246, -7, -50
Sta. 360
BPBM 143492
Sta. 490
oparica reductidenta
BPBM 137686
Sta. 292
Number of
Specimens
13
10
22
Height
Diameter
13
5
10
14
39
1.68±0.037
(1.49-1.95)
3.00±0.049
(2.81-3.41)
1.71*0.057
(1.52-1.92)
2. 96±0.068
(2.72-3.34)
1.93±0.027
(1.69-2.15)
3.40.c0.036
(3.11-3.74)
2.12±0.056
(1.85-2.32)
3.48+.0.081
(3.25-3.97)
2.18*0.063
(1.92-2.54)
3.51*0.069
(3.15-3.94)
2.19±0.060
(1.99-2.35)
3.68±0.038
(3.58-3.77)
2.41±0.044
(2.19-2.62)
3.77±0.038
(3.58-3.94)
BPBM 137609, 12, -15
Sta. 291
50
2.25±0.062
(1.99-2.81)
2.50±0.024
(2.19-2.88)
2.05±0.048
(1.89-2.35)
2.18±0.025
(1.92-2.72)
3.78±0.060
(3.48-4.30)
4.17±0.034
(3.71-4.87)
3.56±0.072
(3.38-4.01)
3.69±0.027
(3.31-4.24)
H/D Ratio
0.559±0.0080
(0.488-0.590)
0.572±0.0046
(0.553-0.597)
0.563±0.0052
(0.522-0.614)
0.607±0.0099
(0.571-0.660)
0.611±0.0061
(0.579-0.646)
0.596±0.0148
(0.540-0.628)
0.636±0.0108
(0.589-0.690)
0.597±0.0100
(0.545-0.654)
0.599±0.0037
(0.524-0.638)
0.577±0.0074
(0.545-0.607)
0.591±0.0049
(0.528-0.728)
Whorls
4 1/4+
(4 1/2-5)
4 5/8+
(4 1/2-5 1/8)
(4 3/4-5 1/4)
5 3/8
(5 1/8-5 5/8)
5 1/2-
(5-6)
5 3/8+
(5-5 3/4)
5 5/8+
(5 3/8-6)
5 1/2-
(5-6 1/8)
5 5/8+
(5 1/4-6 1/4)
5 1/8+
(5-5 1/2)
5 3/8+
(5-6 1/8)
number, 2 (21.1 per cent), 3 (71.0 per cent), or 4 (7.9 per cent),
extending posteriorly about three-sixteenths of a whorl: upper
parietal high and bladelike, expanded and serrated above on
posterior quarter, with gradual anterior descension until just before
anterior end; 2nd parietal normally with elevated posterior portion
slightly shorter and higher, sharply descending to an anterior
threadlike two-thirds that terminates slightly beyond anterior end of
upper parietal; 3rd parietal, when present, similar in structure to
2nd, usually slightly reduced in height and length of posterior
elevated portion; 4th parietal, when present, a low threadlike trace,
not elevated posteriorly, situated below 3rd parietal. Columellar
barrier a raised threadlike ridge, lying parallel to plane of coiling
posteriorly, slanting slightly downward anteriorly, moderately re-
cessed within aperture. Palatal barriers normally 4 (86.8 per cent),
occasionally 3 (7.9 per cent) or 2 (5.3 per cent), relatively short,
extending about one-eighth whorl: lower basal in position, high and
crescentic, with rather sharp anterior descension, moderately recessed
within aperture; 2nd palatal normally slightly higher, longer, with
more gradual anterior descension; 3rd palatal, when present,
moderately reduced in height, with much more gradual anterior
descension, more deeply recessed within aperture; 4th palatal, when
present, greatly reduced in height, a raised lamellar or threadlike
ridge, very short, deeply recessed within aperture, lying slightly
below level of upper parietal.
The very crowded and numerous radial ribs,
smaller diameter, usually barely perforate umbilicus,
and well-developed palatal barriers combine to sepa-
rate the nominate subspecies from both Ruatara
oparica reductidenta and Ruatara oparica normalis.
The former differs most obviously in having no palatal
barriers or at most one or two small tubercules on the
basal and lower palatal margins, while R. oparica
normalis differs in its larger size, fewer and less
crowded radial ribs, and generally more elevated spire.
The progressively recessed parietals and massive
columellar callus separate Ruatara koarana. All
Orangia and the barely perforate Opanara differ in
their much larger and more prominent palatal barriers.
Description. — Shell slightly larger than average, with 5
relatively tightly coiled whorls. Apex and spire strongly elevated,
broadly rounded above, last whorl descending slightly more rapidly,
H/D ratio 0.577. Embryonic whorls 1%, sculpture eroded except for
faint traces of radial ribbing in sutures. Postnuclear whorls with
prominent, broad, lamellar, slightly protractively sinuated radial ribs,
119 on the body whorl, whose interstices are 2-4 times their width.
Microsculpture of prominent, moderately widely spaced radial riblets
crossed by exceedingly fine and crowded spiral riblets. Sutures
moderately impressed, slightly channeled on portions, whorls almost
evenly rounded on outer margins with somewhat flattened basal
margin. Color light yellowish-horn with very vague, irregular, light
reddish-brown flammulations. Umbilicus barely perforate, contained
more than 30 times in the diameter. Aperture elongately ovate with
evenly rounded outer margin, somewhat flattened basal margin,
inclined about 5° from shell axis. Parietal barriers 3, extending three-
sixteenths of a whorl: upper a bladelike ridge with relatively sharp
anterior descension, only slightly higher and expanded on posterior
third; 2nd lamella with anterior half threadlike, extending further
SYSTEMATIC REVIEW
273
reductidenta
Rapa
Island
FlG. 116. Geographical distribution of Ruatara oparica.
past lip edge than upper, the posterior third high and almost crescent
shaped; lower parietal similar to 2nd, but slightly deflected
downward on posterior portion and not quite as high. Columellar
barrier a prominent, narrow ridge, slanting downward at a 45° angle
across heavy baso-columellar callus. Palatal barriers 4: lower, a
small nodular ridge at baso-columellar margin, slightly protruding
above heavy basal callus; 2nd and 3rd high, prominent, rounded,
crescentic, extending about one-eighth whorl; 3rd more gradually
descending anteriorly; upper palatal very low, ridgelike, slightly
crescent shaped, narrow, much less prominent than others, situated
opposite upper parietal. Height of lectotvpe 1.84 mm., diameter 3.19
mm.
Lectotype. — Austral Islands: Rapa ( = Opara).
Collected by Hugh Cuming. BMNH 1962705/1.
Range. — Slopes of Mt. Tanga, Rapa Island,
Austral Islands.
Paratypes. - BMNH 1962704/2-5.
Material. — Rapa (17 specimens, BMNH
1962704/1-5, BMNH, FMNH 46378 ex Webb, Gude);
south Mt. Tanga (Station 466) at 700-800 ft. elevation
under stones and on dead leaves (25 specimens, BPBM
143113-5).
Remarks. — The Hugh Cuming expedition
through Polynesia is known to have been on Rapa
from May 13, 1828 to May 17, 1828 (St. John, 1940, p.
88). Specimens of Ruatara oparica in the British
Museum (Natural History) from the Cuming collec-
tion and all material from old collections (several
individuals were not listed) agreed with the population
from Station 466 on south Mt. Tanga (table
LXXXVII), with 10 df, for the diameter "t" = 0.4593
and for the H/D ratio "t" = 1.1844. While possibly
material from the Anton collection may still exist in
Europe, although currently unrecognized, I have
selected a lectotype from the Cuming specimens. It
differs from the figured example primarily in having
the columellar barrier more sharply deflected
downward.
It is of passing interest to note that recent studies
have managed to localize many of Cuming's species
quite precisely. Thus Cooke and Kondo (1960, pp. 97,
106) show that Pitys pagodiformis (E. A. Smith, 1892)
( = Helix bilamellata Pfeiffer, 1845, not Sowerby,
1844), Lamellovum globosum (Petit, 1843), and the
assimineid Electrina succinea (Sowerby, 1832) came
from the slopes leading to Mt. Morongoto. In the same
paper (pp. 59-62, 191-192) they placed Antonella
trochlearis trochlearis (Pfeiffer, 1842) on Mt. Tanga
and speculated as to the original sites for various
Strobilus. These could not be positively localized by
Cooke and Kondo as no Cuming material was
available to them. H. B. Baker (1938b, p. 62) suggested
that the helicarionid Microcystis ornatella (Beck,
1837) came from near Area, but later (H. B. Baker,
1940, pp. 175-177) made no attempt to deal with local
variation in the helicarionid Hiona orbis (Beck, 1837).
Pfeiffer's emendation of "opanica" to "oparica" is
accepted here, although strict adherence to nomencla-
tural technicalities (Article 32 (a)) would require a
return to "opanica." At the time of description and
during the middle 1800's, Opana and Opara were
recognized alternative spellings for Rapa Island. Hence
Pfeiffer's change could be considered an invalid
emendation. I prefer the more usual oparica spelling
as applied to many other molluscan species and as
used in the great majority of references cited above.
As discussed elsewhere (p. 492), the syndrome of
size reduction accompanied by sculptural crowding is
commonly encountered on Rapa, with Opanara
areaensis, probably O. megomphala, and Orangia
cookei having exactly analogous cases.
The distinction between Ruatara oparica oparica
and R. o. normalis was not recognized during the
initial survey of material. Hence no soft parts of the
Mt. Tanga specimens were borrowed and the anatomy
of the nominate race has not been studied. Probably
specimens suitable for dissection are present in the
Bishop Museum.
Ruatara oparica normalis, new subspecies. Fig-
ures 64h, i; 114a-d; 115; 116.
Diagnosis. — Shell relatively large, diameter 2.70-4.84 mm.
(mean 3.81 mm.), with 5 - (>'j normally coiled whorls. Apex and spire
moderately and evenly elevated, sometimes rounded above, last
whorl generally descending somewhat more rapidly, H/D ratio 0.524-
0.690 (mean 0.6011. Umbilicus either minutely perforate (contained
more than 30 times in the diameter) or completely closed, about
equal in frequency. Postnuclear sculpture of prominent, narrow,
protractively sinuated, relatively widely spaced to crowded radial
ribs, 77-133 (mean 98.5) on the body whorl, whose interstices are 3-5
times their width. Microsculpture of prominent radial riblets. three
to six between each pair of major ribs, with barely detectable traces
of exceedingly fine spiral ribbing. Sutures impressed, whorls strongly
274
SOLEM: ENDODONTOID LAND SNAILS
rounded above, with almost evenly rounded outer and basal margins,
with gradually curved inward columellar extension. Aperture ovate,
strongly rounded above, evenly rounded on outer margins, inclined
about 15° from shell axis. Parietal barriers normally 2 in the Mount
Perahuan and Mount Ruataran populations, normally 3 in speci-
mens from South Rapa, sometimes (less than 11 per cent) with a
fourth or fifth threadlike trace, extending posteriorly somewhat more
than one-eighth whorl: upper parietal a moderately elevated lamellar
blade, expanded and serrated above on posterior quarter, with either
gradual anterior descension or rather sharp anterior descension to a
raised threadlike ridge; 2nd parietal with posterior quarter elevated,
equal in height to upper, expanded and serrated above, with sharp
descension to threadlike anterior half that terminates at, before, or
slightly beyond end of upper parietal; 3rd parietal, when present,
with same structure as 2nd, sometimes situated below 2nd parietal,
sometimes between 1st and 2nd; 4th or 5th parietals, when present,
low and threadlike traces situated below or between lower barriers.
Columellar barrier a broad and rounded lamellar ridge, either deeply
recessed within aperture and abruptly descending, lying parallel to
plane of coiling, or extending further anteriorly and slanting
diagnoally downward partway across columellar callus. Palatal
barriers variable in size and number, normally with 4 (73.6 per cent),
often with 3 (19.2 per cent), only rarely with 0, 1, 2 or 5 palatals (7.2
per cent), barriers when present small to moderate in size, short
crescentic ridges: lower palatal basal in position, usually the highest,
rarely flattened above, with sharp anterior descension; 2nd slightly
reduced in height, sometimes weakly flattened above, generally with
more gradual anterior descension; 3rd still lower, usually slightly
flattened above, generally with quite gradual anterior descension;
4th, when present, greatly reduced in height, a very short threadlike
trace to weakly elevated ridge, lying distinctly below level of upper
parietal.
Ruatara oparica normalis differs from the sub-
species Ruatara o. reductidenta in almost always
having 3 or 4 distinct palatal barriers; R. o. reducti-
denta generally lacks all palatal barriers, although
often (16 per cent) having 1 or 2 very small palatal
tubercles. R. o. oparica is much smaller and with
much more crowded radial ribbing.
Description. — Shell large, with slightly less than 6'/8 normally
coiled whorls. Apex and spire moderately and evenly elevated, last
whorl descending a little more rapidly. H/D ratio 0.632. Apical
whorls l'/2, sculpture eroded. Postnuclear whorls with narrow,
prominent, protractively sinuated, rather widely spaced radial ribs,
81 on the body whorl, whose interstices are 3-5 times their width.
Microsculpture of fine radial riblets. four to seven between each pair
of major ribs, crossed by exceedingly fine and crowded spiral riblets.
Sutures impressed, whorls strongly rounded above, evenly rounded
on outer margins, with basal margin slightly flattened. Color partly
leached from shell, remaining portions light yellow horn, without
traces of reddish flammulations. Umbilicus minutely perforate.
Aperture ovate, with evenly rounded outer margins, slightly-
flattened basally. inclined about 15° from shell axis. Parietal barriers
2, extending posteriorly three-sixteenths of a whorl: upper parietal
high and bladelike, weakly expanded and serrated above on
posterior third, with gradual anterior descension; 2nd parietal with
posterior portion slightly reduced in length and height, rather
sharply descending to a short threadlike portion that terminates
well before anterior end of upper parietal. Columellar barrier a broad
lamellar ridge, parallel to plane of coiling posteriorly, that slants
downward across columellar callus near recessed anterior end.
Palatal barriers 4, low, short, moderately recessed within aperture;
1st basal in position, flattened, serrated and expanded above, with
sharp anterior descension; 2nd reduced in height and length,
flattened above, with more gradual anterior descension; 3rd higher
than 2nd, sinuated on top. with more gradual anterior descension;
4th greatly reduced in height, deeply recessed, very short, lying
slightly below level of upper parietal. Height of holotype 2.83 mm.,
diameter 4.47 mm.
Holotype. — Austral Islands: Rapa Island, Station
490, northeast slope of Mount Ruatara at 750 ft.
elevation. Collected by Yoshio Kondo on July 26, 1934.
BPBM 143492.
Range. — Mt. Perahu, Mt. Ruatara, Mt. Mitiperu,
Morongoto, Kopenena valley, Maraia and Mt. Man-
gaoa, Rapa Island, Austral Islands at various eleva-
tions.
Paratypes. — Same as list of material.
Material. — Rapa: Kopenena valley (Stations 468,
469) at 200-600 ft. elevation (5 specimens, BPBM
143187-90); Maraia at 500 ft. elevation (Station 399) on
dead leaves (30 specimens, BPBM 140385-7); one-half
way up Mt. Mitiperu (Station 454) under stones and in
dirt (7 specimens, BPBM 142926-9); two-thirds way up
Mt. Mitiperu (Station 455) under stones (18 specimens,
BPBM 142936-9); northeast slope of Mt. Ruatara
(Stations 490, 491, 492) at 750-800 ft. elevation (448
specimens, BPBM 135714-6, BPBM 143492-6, BPBM
143526, BPBM 143550); Morongoto at 800 ft. elevation
(Stations 360, 400) in dead fern fronds and under
stones (39 specimens, BPBM 53246, BPBM 144246-50,
BPBM 144339-40); northeast ridge of Mt. Mangaoa
(Stations 526, 527) at 800-1,100 ft. elevation under
stones and on dead leaves (30 specimens, BPBM
138400, BPBM 138402-4, BPBM 143747-9); south slope
of Mt. Perahu (Station 376) at 900-1,000 ft. elevation
under moss on ground (5 specimens, BPBM 140253,
BPBM 140255); east ridge of Mt. Perahu (Stations
446, 451, 452, 509, 512, 513) at 1,200-1,850 ft. elevation
(21 specimens, BPBM 135442, BPBM 135482, BPBM
135569-72, ex BPBM 135488, BPBM 140254, BPBM
142749, BPBM 142823, BPBM 142831, BPBM 142877,
BPBM 142879).
Remarks. — Ruatara oparica normalis has a
scattered distribution (fig. 116) interrupted on south
Rapa by the populations of R. o. reductidenta in the
Maitua and Mt. Tautautu region. On south Rapa it
was taken at low-to-intermediate elevations, only on
Mt. Mangaoa reaching more than 1,000 ft. elevation.
The Mt. Ruatara samples were taken at lower heights,
but on Mt. Perahu it occurred sparsely at 900-1,850 ft.
elevation.
Much of the general variation has been discussed
above, including the dichotomy in parietal barrier
frequency between north Rapa (Mt. Perahu and Mt.
Ruatara) and south Rapa (fig. 115). Size and shape
variation was moderate (table LXXXVII). The speci-
mens from Maraia (Station 399) were distinctly
smaller than most examples seen, while the sample
from Mt. Ruatara (Station 490) contained very large
shells. The large number collected at Mt. Ruatara (448
specimens) certainly introduced a bias when only the
39 specimens sorted out by the Bishop Museum staff
as gerontic and adult were measured, but the much
larger maximum size indicates that this is a real
difference. Other samples were approximately evenly
incremental in diameter, with a jump of 0.39 mm. from
SYSTEMATIC REVIEW
275
Station 360 (Morongoto) to the large Mt. Ruatara
(Station 490) population. Depressed shells were taken
at Maraia (Station 399) (mean H/D ratio 0.563) while
those from Mt. Perahu were markedly elevated (mean
H/D ratio 0.636). The remaining five samples had
mean H/D ratios of 0.596-0.611. These extremes are
significantly different from their nearest mean.
Comparing Station 399 (mean 0.563) with Station 526
(mean 0.596), with 25 df, "t" = 2.5798; comparing
Station 527 (mean 0.611) with the Mt. Perahu shells
(mean 0.636), with 21 df, "t" = 2.1391. The possible
meaning of these differences has been discussed above.
Rib variation did not depart from a normal
distribution (table LXXXV). Specimens from north
Rapa and south Rapa had virtually identical rib
counts and frequency (respectively, 99.8 and 96.6 ribs,
8.12 and 7.98 ribs/mm.). The minor difference probably
was caused by the greater mean diameter (3.88 mm.)
of the north Rapa Mt. Ruatara population and its
higher percentage of gerontic individuals with crowded
ribbing on the last quarter whorl. Rib counts and rib
frequencies overlapped those of the other two sub-
species (tables LXXXV, LXXXVI), but the differences
in means are obviously significant (table LXXXVI).
Since the selected population data in Table LXXXVII
so closely approximated the means from the sub-
species, SEM's were not calculated for the entire
samples.
The name normalis refers to the generalized
appearance of those shells compared with the probable
derivatives R. oparica oparica and R. oparica reducti-
denta.
Description of soft parts. — Foot and tail partly retracted,
tapering posteriorly, rounded behind. Sole undivided, pedal grooves
typical, no caudal horn or middorsal groove visible. Slime network
inconspicuous.
Body color yellow-white, without darker markings.
Mantle collar (MC) elongated, with thickened edges, no
glandular extension onto pallia] roof.
Pallial region extending apically about five-eighths of a whorl.
Lung roof clear except for thick clusters of white granules on top of
kidney. Kidney about 1.78-2.14 mm. long, narrow anteriorly, with
broadly expanded rectal arm about one-third to one-half of length
depending on degree of contraction. Ureter typical, opening just
beyond termination of rectal kidney arm. Heart about one-third
length of kidney, not parallel to hindgut. Principal pulmonary vein
slender, unbranched. fading out just before hindgut. Hindgut
following palatal-parietal margin just above apex of pallial cavity,
then slanting downwards.
Ovotestis (fig. 64h, G) of many palmately clavate alveoli
imbedded in first whorl above stomach reflexion, more than in
Opanara areaensis. Hermaphroditic duct (GD) slender at first,
markedly expanded and convoluted medially, narrowing abruptly
before reflexing onto talon shaft. Albumen gland (GG) small,
compact, typical. Talon (GT) with expanded head, narrow neck just
before junction with hermaphroditic duct, base expanded. Prostate
( DG) with one or two rows of large acini opening into a narrow tube,
shorter than free oviduct. Uterus (UT) with normal two parts.
Vas deferens (VD) very slender, reflexing at penioviducal angle,
entering penis just below apex of penis at top of pilaster. Penial
retractor (PR) arising from diaphragm, inserting directly onto penis
head just before entrance of vas deferens, no fleshy extension to
penis head. Penis (P) about 3.3 mm. long, gradually tapering
apically, internally with a large, complexly corrugated pilaster (fig.
64i) becoming bifurcated basally, terminating at penis apex. Atrium
(Y) broad, short.
Free oviduct (UV) slightly longer than prostate, tapering to
vagina. Spermatheca (S) with very slender shaft, expanded head
buried in albumen gland. Vagina (V) clearly separable, but short.
Free muscle system typical. Right ommatophoral retractor
passing through penioviducal angle.
Buccal retractors not split, uniting with tail fan just before
termination of columellar muscle. Esophagus typical. Stomach
extending almost one whorl, starting one-eighth whorl above pallial
cavity apex. Intestinal looping typical.
Jaw lost in processing. Radula with large teeth, central 14fi long
and 13,u wide, laterals 4 to 6. with more than 10 marginals.
(Based on BPBM 143492, whole specimens 4.18 mm. in diameter
with 5'/2 whorls and 4.28 mm. with 5Vs+ whorls, additional
fragmentary specimens and BPBM 140385, 3.42 mm. with 5 whorls. )
Ruatara oparica reductidenta, new sub-
species. Figures 64j; 114e; 115; 116.
Diagnosis. — Shell relatively large, diameter 3.29-4.34 mm.
(mean 3.74 mm.), with 5 - 6'/s normally coiled whorls. Apex and spire
moderately and evenly elevated, occasionally slightly rounded above,
last whorl generally descending a little more rapidly, H/D ratio
0.528-0.698 (mean 0.563). Umbilicus completely closed, rarely
narrowly perforate. Postnuclear whorls with narrow, prominent,
often lamellar, protractively sinuated radial ribs, 66-95 (mean 78.4)
on the body whorl, whose interstices are 2-3 times their width.
Microsculpture of fine radial riblets, three to five between each pair
of major ribs, with barely visible traces of spiral microribbing.
Sutures impressed, whorls strongly rounded above, with almost
evenly rounded outer and basal margins. Aperture ovate, strongly
rounded above, inclined about 15° from shell axis. Parietal barriers
variable in number, normally 3 (77.7 per cent) or 4 (11.4 per cent),
sometimes 2 (8.2 per cent) and very rarely (2.7 per cent) only 1 or 5,
generally quite low, extending posteriorly less than three-sixteenths
of a whorl: upper parietal sometimes weakly expanded and serrated
above on posterior quarter, with gradual anterior descension, other
times a raised threadlike ridge for entire length; 2nd parietal usually
raised and expanded above slightly on posterior quarter, with quick
descension to a low threadlike ridge terminating slightly in front of
upper parietal; 3rd parietal normally a low threadlike ridge equal in
length to 2nd parietal; 4th parietal, when present, either a shortened
trace between one of the upper pairs, or a threadlike trace lying
below 3rd parietal. Columellar barrier a deeply twisted, broadly
rounded lamellar ridge, normally slightly twisted downward at
anterior end. Normally the palatal wall bears only a weak callus
that terminates near basal lower palatal margin (84.0 per cent), often
there is a short, low tubercle occupying the position of the 1st
palatal (15.5 per cent) and very rarely (0.5 per cent) there is a weak
trace of a 2nd palatal.
The normal complete absence of palatal barriers is
the primary character separating Ruatara oparica
reductidenta from the nominate subspecies. The latter
form normally has a higher percentage of individuals
with a measurably perforate umbilicus.
Description. — Shell relatively large, with 6'/e normally coiled
whorls. Apex and spire strongly and almost evenly elevated, last
whorl descending a little more rapidly, H/D ratio 0.661. Apical
whorls 1%, sculpture eroded. Postnuclear sculpture of narrow,
prominent, protractively sinuated radial ribs, 92 on the body whorl,
whose interstices are 2-3 times their width. Microsculpture of fine
radial riblets, three to five between each pair of major ribs, with
exceedingly vague traces of spiral ribbing. Sutures deep, whorls
276
SOLEM: ENDODONTOID LAND SNAILS
strongly rounded above, with evenly rounded outer margins, baso-
columellar margin gently extended inward. Color light yellow horn,
without traces of reddish flammulations. Umbilicus completely
closed. Aperture ovate, with evenly rounded outer margins, inclined
about 15° from shell axis. Parietal barriers 3, extending posteriorly
less than three-sixteenths of a whorl, greatly reduced in size; upper
parietal a moderately elevated lamellar blade, very weakly expanded
and serrated above on posterior quarter, with gradual anterior
descension; 2nd parietal almost equally elevated on posterior
quarter, with sharp anterior descension to a low threadlike ridge that
terminates anteriorly in front of upper parietal; 3rd parietal barely
expanded and serrated above on posterior quarter, anterior five-
eighths a low threadlike ridge. Columellar wall with a deeply
recessed, broadly rounded lamellar ridge, whose anterior end twists
slightly downward. Palatal wall without trace of barriers, a
moderately heavy callus extending from columellar-parietal margin
and gradually weakening to union of basal and lower palatal walls.
Height of holotype 2.70 mm., diameter 4.08 mm.
Holotype. — Austral Islands: Rapa Island, Station
291, back of Aurei at Maitua, 500-600 ft. elevation.
Collected under stones by Donald Anderson and C. M.
Cooke, Jr. on July 12, 1934. BPBM 137609.
Range. — Maitua and northwest of Mt. Tautautu
at 450-800 ft. elevation, Rapa Island, Austral Islands.
Paratypes. — Same as list of material
Material. — Rapa: Maitua at lowest coffee patch
(Station 302), 100 yd. below Station 291 at 450 ft.
elevation (1 specimen, BPBM 137807); coffee plan-
tation (Stations 291, 426) in Maitua area at 500-600 ft.
elevation (275 specimens, BPBM 137609-21, BPBM
137641-2, BPBM 137643-5, BPBM 137669-71, BPBM
144524-7); from coffee patch to cliff base, one-quarter
mile (Station 316) east of Station 292 at 500-700 ft.
elevation (6 specimens, BPBM 137948, BPBM 144023-
4); 100 yd. below cliff base, Maitua, about 75 yd.
(Stations 292, 293, 305A, 427, 429) above Station 291 at
700-800 ft. elevation (59 specimens, BPBM 135523-4,
BPBM 137686-91, BPBM 137730, BPBM 137843,
BPBM 143885-8, BPBM 144566-7); Maitua, between
cliff (Station 306) and Station 305 (1 specimen, BPBM
137869); Maitua area (Stations 317, 318) at 700-750 ft.
elevation (18 specimens, BPBM 144041-2, BPBM
144087-9); Maitua area, along marae (Station 353)
below Mangaoa (5 specimens, BPBM 140012-6);
Maitua area (Station 307) at unspecified elevation (1
specimen, BPBM 143917); under one log (Station 358)
in Maitua area at unspecified altitude (29 specimens,
BPBM 135697, BPBM 135700, BPBM 142534-5);
northwest of Mt. Tautautu (Station 342) at 600-700 ft.
elevation (15 specimens, BPBM 142407-12).
Remarks. -- Specimens of Ruatara oparica re-
ductidenta were found in forest, ecotonal (Station 353)
and plantation (Stations 291, 426) areas in the Maitua
region, with one record (Station 342) from the adjacent
Mt. Tautautu. No differences were noted between the
native forest and coffee plantation specimens. While
examples from Station 292 averaged slightly smaller
(table LXXXVII) than those from Station 291 (with
56 df, "t" = 1.7821) and were insignificantly lower ("t"
= 1.1258), this difference probably is the result of
measuring bias. As can be seen from Figure 115, a few
specimens of R. oparica normalis approach the barrier
condition of R. o. reductidenta. These are scattered
through several populations and in both size and
ribbing agree with R. o. normalis.
The name reductidenta refers to the reduced
palatal barriers.
Description of soft parts. — Only fragmentary extracted
specimens were available for dissection. Most parts of the genitalia
were observed and corresponded exactly with Ruatara oparica
normalis. Only the penis is figured (fig. 64j). Varying in length from
2.6-3.4 mm., internally it was identical with that of Ruatara oparica
normalis.
Radula with very large teeth, central 16u long, 13u wide.
Laterals 4 or 5 in number, marginals 10 or 11 with edge turned under.
(Based on BPBM 137609, fragmentary examples.)
Genus Orangia, new genus
Endodontidae having typical apical sculpture, with (sporadica
and maituatensis) or without (cookei) secondary spiral cording,
normal spiral microsculpture greatly reduced, major sculpture of
widely spaced (sporadica) to very crowded (cookei tautautuensis),
protractively sinuated radial ribs. Apex and spire moderately
elevated, last whorl usually not descending much more rapidly,
periphery markedly angulated (sporadica and cookei cookei) or
protruded (maituatensis) to evenly rounded (cookei tautautuensis).
Whorls about 6, reduced in number slightly in cookei tautautuensis
and maituatensis. Umbilicus narrowly open in juveniles, barely
perforate or usually closed in adults (fig. 118). Parietal barriers 2,
upper lamellate for entire length, lower with threadlike anterior
portion terminating opposite or before anterior end of upper.
Columellar barrier reaching lip margin (cookei tautautuensis) to
deeply recessed (cookei cookei, sporadica, and maituatensis).
Palatal barriers normally 4, rarely 5, variable in height. Genitalia
with a fleshy extension of penis head merging with penial retractor,
markedly subapical insertion of the vas deferens, internally with two
pilasters that become high, thin lamellar ridges apically. Penial
retractor originating from diaphragm. Anatomy otherwise typical of
Endodontidae.
Type species. — Orangia cookei cookei, new
species and subspecies.
The generally angulated periphery, normal pres-
ence of a supraperipheral sulcus, large size, strong
color patterns, prominent and protractive radial ribs,
and the fleshy extension of the penis head into the
penial retractor are all characters that Orangia shares
with Australdonta. The differences are many. Orangia
has a secondary microsculpture of spiral cords (or
none); Australdonta spiral grooves (fig. 124). Orangia
has 2 parietals; Australdonta usually 3 or 4, often
more. Orangia has a prominent columellar barrier;
Australdonta, except rarely, lacks a columellar.
Orangia has 4 palatals; most Australdonta have 5,
although A. pseudplanulata, A. raivavaeana, and A.
tubuaiana have 3 or 4 palatals and they are absent in
A. radiella. Orangia has the umbilicus closed or
barely perforate in adults; Australdonta has the
umbilicus rather widely open. The penial pilasters in
Orangia are narrowed and greatly elevated apically
(fig. 121c); in Australdonta the pilasters are grossly
expanded and thickened above (fig. 125b, e), never
elevated into narrow blades. Orangia species average
nearly six whorls; all Australdonta species average
SYSTEMATIC REVIEW
Rapa Island
277
c tautauensis
•jf cookei
Q sporadica
X maituatensis
FIG. 117. Distribution of Orangia.
much less than six whorls and thus show more rapid
increase in whorl width.
Orangia and Australdonta seem to be parallel in
their shared conchological features, although they
probably both were derived from the Mautodontha
series. The penial pilaster pattern of Orangia is seen in
the other Rapan genera and is quite distinct from the
Mautodontha- Australdonta pattern. I consider that
Orangia is a specialized, local derivative of the
Opanara complex endemic to Rapa.
Speciation within the genus is simple and un-
complicated. O. cookei, which I consider is the most
generalized species, lacks the secondary spiral cording,
has a rounded or obtusely angulated periphery, more
crowded ribbing, and occurs as three geographically
isolated subspecies (fig. 117). O. maituatensis, which
has secondary spiral cording above and below the body
whorl periphery, a right-angled periphery, much more
depressed spire, less crowded ribbing (mean ribs/mm.
6.78), and a prominent supraperipheral sulcus is
restricted to the Maitua area. It is much more similar
in appearance to O. cookei cookei than to O. cookei
tautautuensis that lives in the same region. O.
sporadica is less sharply angulated than O. maitua-
tensis, has a very prominent supraperipheral sulcus,
widely spaced radial ribbing (mean ribs/mm. 4.35), a
prominent secondary microsculpture below the body
whorl periphery, and occurred at scattered localities
FIG. 118. Umbilical closure in Orangia cookei cookei. a-b,
juveniles; c, subadult, d, adult. Station 312, Mt. Tepiahu, Rapa
Island, Austral Islands. Scale line equals 1 mm. (MM).
278
SOLEM: ENDODONTOID LAND SNAILS
over large areas of Rapa (fig. 117). It was not taken at
the same localities as O. cookei cookei, O. c.
tautautuensis, or O. maituatensis, but there is a
possibility that O. c. montana inhabits the same
stations on Mt. Perahu. At Station 451, which extends
over 300 ft. vertically and an unknown distance
horizontally, 16 montana and one sporadica were
collected. Stations on Mt. Perahu were much less
rigorously localized than in the Maitua area, so that
the two taxa may be ecologically separated.
Umbilical closure in Orangia is accomplished
differently than in Ruatara. In the latter (fig. 113d),
the umbilicus is essentially minutely perforate from
the apical whorls onward, with the columellar wall
straight or only slightly curved inward until
adulthood, when heavy callus formation apparently
(fig. 114a, c) alters the columellar configuration. In
Orangia the umbilicus is narrowly open during early
growth stages, with a curved inward growth of the
columellar region (fig. 118) providing complete or
nearly complete umbilical closure. The proportions of
closed versus perforate umbilici differ between taxa
open
closed
a>
100-
90
80-
70-
60-
IL)
O
CL>
Q_
8
llll
74
CO
n
17
25
50-
40-
30-
20
10
0
FlG. 119. Relative proportions of closed and barely perforate
umbilici in Orangia.
15
12
(fig. 119). Except in O. maituatensis, more than 60 per
cent of each form have the umbilicus completely
closed. In the latter species, one-fifth have a closed
umbilicus, four-fifths a perforate umbilicus contained
an average of 26.7 times in the diameter.
Size variation is quite minor (table LXXXI), with
Orangia cookei tautautuensis being conspicuously
(14.5 per cent) smaller, O. cookei montana slightly (6
per cent) larger, and the other taxa virtually identical.
Variation in H/D ratios is similarly minor, with the
greater depression of O. maituatensis (8.6 per cent)
attributable to a 5.9 per cent decrease in shell height.
The comparatively great elevation of O. cookei
tautautuensis correlates with the reduction in diameter
(14.5 per cent), which far exceeds the reduction in
height (7.3 per cent).
Sculptural variation is rather large. O. sporadica
is sharply differentiated in both rib count and spacing
(see table LXXXVIII), and is immediately separable
visually by these characters alone (fig. 123f). The other
taxa show substantial overlap in both characters
although displaying mean differences. The character of
the sculpture is the same, but the spacing differs. A
scatter diagram (fig. 120) of ribs plotted against
ribs/ mm. showed that O. sporadica, O. maituatensis,
and O. cookei cookei have the same pattern, while O.
cookei montana and O. cookei tautautuensis are offset,
respectively, to the left and right of the main pattern.
Regression lines were not plotted for the other taxa,
since only for O. cookei were there many observations.
Anatomical variation within Orangia was minor.
O. maituatensis had a much longer penis and longer
free oviduct (see fig. 121) than the other species, with
corresponding slight alterations in penial pilaster
patterns. Only fragmented specimens of O. sporadica
were available and no material adequate for dissection
was seen of O. cookei tautautuensis.
KEY TO THE GENUS Orangia
1. Adult shells with more than 70 ribs; ribs/mm, more than 5.60.
2
Adult shells usually with much less than 70 ribs; ribs/mm,
usually much less than 5.25 Orangia sporadica, new species
2. Body whorl rounded or obtusely angulated, not protruded; no
secondary spiral cording; mean H/D ratio more than 0.500.
3
Body whorl right angled, keel protruded; secondary spiral
cording present; mean H/D ratio less than 0.475.
Orangia maituatensis, new species
3. Columellar barrier extending well in front of callus apex;
periphery obtusely or evenly rounded; rarely a supraperipheral
sulcus present 4
Columellar barrier reaching just to top of callus apex; periphery
usually obtusely angulated; a supraperipheral sulcus normally
present Orangia cookei cookei, new subspecies
4. Mean diameter about 3.50 mm.; mean H/D ratio about 0.550;
ribs very crowded, about 10.00 ribs/mm.; Mt. Tautautu.
Orangia cookei tautautuensis, new subspecies
Mean diameter about 4.25 mm.; mean H/D ratio about 0.515;
ribs much less crowded, about 7.58 ribs/mm.; Mt. Perahu.
Orangia cookei montana, new subspecies
SYSTEMATIC REVIEW
279
.
11.5
10.5
9.5
8.5
7.5
6.5
5.5
4.5
3.5
• c.cookei
Q c.montana
r~| c.tautautuensis
-^ maituatensis
-^ sporadica
D
D
O
O
O
* *
40
50
60
70
90
100
110
120
Ribs
FIG. 120. Correlation of ribs and ribs/mm, in the endodontinine genus Orangia.
Orangia cookei, new species.
Differences between the three morphs grouped
here are constant. No intergradation was observed.
Despite this, the similarities are so many that
subspecific designations have been adopted. The forms
are geographically isolated, with the nominate sub-
species from the Orangi-Tepiahu-Tanga region more
closely resembling the Mt. Perahu Orangia cookei
montana than its neighboring form from Mt. Tau-
tautu, O. c. tautautuensis. Only nine specimens of the
latter from one station were available, and I have
chosen a conservative course in treating it as a
subspecies.
The subspecies are as follows:
O. c. cookei has the columellar barrier reaching
only slightly past the columellar callus apex; the
periphery usually is obtusely angulated and with a
noticeable supraperipheral sulcus; the parietals extend
almost one-quarter whorl and the palatals about one-
eighth whorl; 1st palatal distinctly smaller than 2nd
and 3rd; there are about 7.75 ±0.012 ribs/mm, on the
body whorl.
O. c. montana has the columellar barrier extend-
ing about half way across the columellar callus; the
periphery usually is obtusely rounded and lacks a
supraperipheral sulcus; the parietals extend about one-
quarter whorl and the palatals about one-eighth
whorl; 1st palatal subequal or equal to 2nd palatal;
there are about 7.57 ± 0.20 ribs/mm, on the body
whorl.
O. c. tautautuensis has the columellar barrier
reaching almost to the lip margin; the periphery is
1mm
PR
PP
FIG. 121. Anatomy of Orangia: a-c, Orangia cookei cookei, BPBM 143116. a, pallial region, b, genitalia with most of ovotestis
omitted, c, interior of penis; d-f, Orangia cookei montana, BPBM 135433. d, genitalia with most of ovotestis omitted, e-f, details of penis
interior; g-i, Orangia maituatenais, BPBM 144044, -568. g, genitalia with most of ovotestis omitted, h-i, interior of penis region; j-k,
Orangia sporadica, BPBM 140404. j, exterior of penis, k, interior of penis. Scale lines equal 1 mm.
280
SYSTEMATIC REVIEW
281
2JOT
2.50
230
2.10
1.90
1.71
j^. cookei cookei
Q c. montana
[~~j c. tautautuensis
D
DD
* *
J
I
3.16 3.35 3.55 375 3.95
Diameter in mm.
4.14
4.34
4.54
4.74
FIG. 122. Scatter diagram showing relationship of height to diameter in subspecies of Orangia cookei.
rounded and there is no supraperipheral sulcus; the
parietals extend to or beyond the line of vision and the
palatals about one-quarter whorl; all the palatals are
reduced in height and the 1st is distinctly smaller than
the 2nd; there are about 10.05 ± 0.67 ribs/mm, on the
body whorl.
Size and shape differences are noticeable, but with
quite considerable overlap. Thus, O. c. cookei and O. c.
montana are identical in H/D ratios, but montana is
significantly larger (comparing the diameter of Station
466 adult cookei cookei with Station 509 adult cookei
montana, with 37 df, "t" = 2.5000). A scatter diagram
using all adult specimens of the two subspecies (fig.
122) shows that O. c. montana clusters at the upper
end of the range and O. c. cookei at the middle
portion, although the largest O. cookei cookei is only a
trifle smaller than the largest O. cookei montana.
Since the H/D ratios are identical, the regression lines
would be the same and have not been calculated.
Orangia cookei tautautuensis is obviously smaller and
higher (fig. 122).
The changes involved in deriving montana from
cookei — lengthening of the columellar barriers,
decrease in peripheral angulation, increase in barrier
size and slight size increase — are minor. Considerably
more change is required to alter cookei into tautau-
tuensis — the columellar barrier is greatly lengthened,
both parietal and palatal barriers are lengthened by
50-100 per cent with the latter decreased in height; the
whorl count is lowered, diameter reduced 14.5 per cent,
but the height only 7.3 per cent, resulting in a 8.2 per
cent increase in H/D ratio; rib count increased by 5.7
(6.2 per cent) on the body whorl with the ribs/mm,
increasing from 7.78 to 10.05 (29.2 per cent). The
increase is rib number is not statistically significant,
since with 45 df, "t" = 1.0048, when specimens of O.
cookei cookei from Station 466 are compared with
specimens of O. c. tautautuensis in respect to rib
count. The difference in rib spacing for the same sets is
significant (with 45 df, "t" = 2.038), as are the
differences in diameter and H/D ratios for adults from
Station 478 (c. tautautuensis) and Station 466 (c.
cookei), since with 30 df, "t" = 7.5763 for diameter and
"t" = 3.2091 for H/D ratio.
As discussed below Orangia cookei tautautuensis
is one of several Rapa Island taxa characterized by
diminution in size, crowding of ribs, and changes in
proportions.
Orangia cookei cookei, new species and sub-
species. Figures 118; 121a-c; 122; 123a-b.
Diagnosis. — Shell of average size, diameter 3.36-4.57 mm. (mean
4.00 mm. I. with 5' 4 - 6' 4 normally coiled whorls. Apex flat or weakly
elevated, spire moderately elevated, last whorl descending much
more rapidly in gerontic individuals, normally slightly deflected
below periphery in adults, H/D ratio 0.424-0.585 (mean 0.510).
Umbilicus narrowly open in juveniles, barely perforate or closed in
al
FIG. 123. a-b, Orangia cookei cookei, new species and subspecies, a, Station 466, Mt. Tanga, Rapa Island, Austral Islands. Holotype.
BPBM 143116; 6, Station 325, Mt. Orangi, Rapa Island, Austral Islands. Paratype. BPBM 139938; c, O. cookei montana, new subspecies.
Station 509, Mt. Perahu, Rapa Island, Austral Islands. Holotype. BPBM 135433; d, O. cookei tautautuensis, new subspecies. Station 478,
Rapa Island, Austral Islands. Holotype. BPBM 143300; e, O. maituatensis, new species. Station 308, Maitua, Rapa Island, Austral Islands.
Holotype. BPBM 143940; f. O. sporctdica. new species. Station 340, Mt. Tautautu, Rapa Island, Austral Islands. Holotype. BPBM 144151.
Scale lines equal 1 mm. Figures a, c, e-fb\' YK reproduced through the courtesy of Bemice P. Bishop Museum; b, d (MM).
282
SYSTEMATIC REVIEW
TABLE LXXXVIII. - RIB VARIATION IN ORANGIA
283
Name
sporadlca
maituatensis
cookei cookei
All
Sta. 466
Sta. 534
Sta. 312
cookei montana
cookei tautautuensis
Number of
Specimens
12
110
44
50
Ribs
50.8±2.69
(38-64)
81.1±2.52
(71-89)
92.6
(72-135)
91.3±1.76
(71-135)
92.2*1.39
(72-117)
103.4±3.42
(88-115)
104.8±3.74
(81-120)
98.3±7.97
(88-114)
adults. Postnuclear sculpture of narrow, prominent, strongly protrac-
tively sinuated radial ribs, 72-135 (mean 92.6) on the body whorl,
whose interstices are 2-3 times their width. Microsculpture of fine
radial rihlets, five to nine between each pair of major ribs, crossed by
extremely fine and crowded spiral riblets. Sutures impressed, whorls
moderately rounded above, somewhat flattened to level of weak
supraperipheral sulcus, which is occasionally absent. Periphery
obtusely angulated (rounded in gerontic individuals), base of shell
evenly rounded, with flattened inward extension of columellar
region, a heavy columellar callus present. Aperture ovate, with
obtusely angulated periphery, inclined slightly more than 15° from
shell axis. Parietal barriers 2, extending posteriorly almost one-
quarter whorl: upper high and bladelike, posterior third to half
markedly expanded and serrated above, with very gradual anterior
descension that accelerates during last eighth of length; 2nd parietal
with posterior elevated portion equal in height and superior
expansion, slightly shorter, sharply descending anteriorly to a low
threadlike portion that stops before anterior end of 1st parietal.
Columellar barrier high and crescentic, twisting slightly downward to
top of columellar callus. Palatal barriers 4, very rarely 5, extending
posteriorly about one-eighth whorl: lower basal in position, ex-
panded, serrated, and flattened above on posterior third with very
gradual anterior descension, moderately recessed within aperture;
2nd and 3rd palatals slightly higher posteriorly, with equally gradual
anterior descension, not recessed more deeply within aperture; 4th
palatal supraperipheral, reduced in height, equally expanded above,
with very gradual anterior descension, reaching slightly further
anteriorly.
Both Orangia sporadica and O. maituatensis
have a prominent microsculpture of spiral cording
visible below body whorl periphery. O. sporadica also
differs in having fewer radial ribs on the body whorl
(38-64) and the apertural barriers greatly reduced in
Ribs/mm.
4.35±0.147
(3.71-5.45)
6.79±0.321
(5.81-7.70)
7.78
(6.31-10.80)
7.77±0.119
(6.31-10.80)
7.75±0.086
(6.51-9.21)
8.54±0.205
(7.79-9.20)
7.58±0.201
(6.27-8.36)
10.05±0.672
(8.78-11.06)
Diameter
3.68±0.109
(3.26-4.31)
3.84±0.156
(3.36-4.44)
3.78
(3.13-4.31)
3.74±0.032
(3.13-4.24)
3.79±0.036
(3.13-4.24)
3.86±0.085
(3.52-4.21)
4.40±0.067
(4.08-4.64)
3.41±0.110
(3.19-3.52)
size. O. maituatensis has somewhat more widely
spaced ribbing (71-89 on the body whorl), a more
depressed shape (mean H/D ratio 0.466), and very
strongly developed apertural barriers. The nominate
subspecies differs from O. cookei tautautuensis by its
larger size, lower H/D ratio, deeply recessed colu-
mellar, and angulated periphery. O. cookei montana is
a much less angulated shell with an extremely long
columellar, and much more prominent parietal and
palatal barriers.
Description. — Shell large, with 5V4 normally coiled whorls. Apex
slightly elevated, lower whorls and spire descending more rapidly,
body whorl slightly deflected below periphery, H/D ratio 0.488.
Apical and early postnuclear whorls with sculpture eroded.
Postnuclear whorls with narrow, lamellate, protractively sinuated
radial ribs, 91 on the body whorl, whose interstices are about 3 times
their width. Microsculpture of fine radial riblets, five to nine between
each pair of major ribs, crossed by exceedingly fine and crowded
spiral riblets that are barely visible under 96 x magnification.
Sutures impressed, whorls moderately rounded above, slightly
flattened laterally above distinct supraperipheral sulcus, periphery
obtusely rounded, lower palatal margin evenly rounded, columellar
margin extended inwardly. Color light yellow-white, with almost
regularly spaced, irregularly shaped, zigzagged, reddish
flammulations that tend to decrease in prominence below periphery
of body whorl. Umbilicus completely closed. Aperture compressedly
ovate, a slight supraperipheral indentation, inclined about 20° from
shell axis. Columellar wall with thick white callus. Parietal barriers
2, extending posteriorly one-quarter whorl: upper high and lamellate,
with posterior half strongly expanded and serrated above, with very
gradual descension anteriorly; 2nd with posterior portion equal in
height and expansion, slightly shorter, with sharp anterior descension
284
SOLEM: ENDODONTOID LAND SNAILS
TABLE LXXXIX. - LOCAL VARIATION IN ORANGIA
Name
cookel cookel
BPBM 140068
Sta. 354
BPBM 137968
Sta. 321
BPBM 143116
Sta. 466
BPBM 144792. -5
Sta. 534
BPBM 139938-9
Sta. 325
cookei montana
BPBM 135433
Sta. 509
BPBM 142827-8
Sta. 451
cookel tautautuensis
BPBM 143300-2
Sta. 478
sporadlca
BPBM 144151
Sta. 340
BPBM 140404, -6
Sta. 401
maltuatensis
BPBM 143940
Sta. 308
Number of
Specimens
17
25
19
10
14
12
Height
1.98±0.068
(1.72-2.12)
1.99±0.023
(1.76-2.15)
2. 03±0.032
(1.82-2.52)
2.11±0.046
(1.79-2.58)
2.10±0.048
(1.82-2.42)
2.10±0.060
(1.79-2.48)
2. 27±0.056
(2.02-2.58)
1.89±0.083
(1.59-2.12)
2. 09±0.065
(1.89-2.35)
2.30±0.063
(2.12-2.48)
1.99±0.166
(1.82-2.32)
Diameter
3. 95±0.060
(3.81-4.14)
3.98±0.028
(3.81-4.30)
3.98±0.027
(3.74-4.30)
4.02±0.057
(3.74-4.60)
4.12±0.058
(3.84-4.37)
4. 13±0.064
(3.74-4.60)
4.36±0.070
(4.03-4.67)
3.42±0.109
(3.05-3.77)
3.83±0.057
(3. 64-4. 04)
4. 12±0.064
(3.91-4.30)
4. 25±0.205
(3.84-4.47)
to threadlike portion that stops before end of upper parietal.
Columellar barrier high and crescentic, slightly twisted downward to
upper edge of columellar callus. Palatal barriers 4, extending
posteriorly about one-eighth whorl: lower slightly reduced in height,
expanded and serrated above on posterior half with gradual anterior
descension; 2nd and 3rd palatals higher, equally expanded and
serrated above, with very gradual anterior descension, not recessed
further within aperture; 4th palatal supraperipheral, greatly reduced
in height, expanded and serrated above, with gradual anterior
descension, reaching slightly nearer lip margin. Height of holotype
2.01 mm., diameter 4.11 mm.
Holotype. — Austral Islands: Rapa Island, Station
466, hillside on south side of Mt. Tanga at 700-800 ft.
elevation. Collected under stones by Donald Anderson
on July 23, 1934. BPBM 143116.
Range. — Vicinity of Mt. Tanga, Mt. Tepiahu, and
Mt. Orangi at 300-850 ft. elevation, Rapa Island,
Austral Islands.
Paratypes. — Same as list of material.
Material. -• Rapa Island: Mt. Tanga (Stations
466, 532, 534) at 300-800 ft. elevation under stones
H/D Ratio
0.501±0.0183
(0.444-0.543)
0.501±0.0048
(0.434-0.524)
0.510±0.0062
(0.466-0.585)
0.527±0.0069
(0.457-0.575)
0.505±0.0120
(0.424-0.557)
0.507±0.0075
(0.474-0.564)
0.519±0.0072
(0.485-0.560)
0.552±0.0110
(0.517-0.592)
0.547±0.013
(0.491-0.589)
0.559±0.0086
(0.524-0.580)
0.451±0.0341
(0.411-0.519)
Whorls
5 3/4+
(5 3/4-5 7/8)
6-
(5 1/2-6 1/8)
5 7/8
(5 5/8-6 1/8)
6+
(5 3/4-6 1/4-0
6-
(5 5/8-6 1/4)
5 7/8+
(5 1/2-6 1/4)
(5 3/4-6 1/4)
5 5/8
(5 1/8-6)
6
(5 3/4-6 1/4)
6 1/8+
(6-6 3/8+)
5 3/4+
(5 5/8-6)
(1,091 specimens, BPBM 143116-23, BPBM 143800,
BPBM 144792-8); Pake Bay (Station 321) (39 speci-
mens, BPBM 137968-70); Mt. Tepiahu (Stations 311,
312, 354, 462) from sea level to 850 ft. elevation (140
specimens, BPBM 137924-6, BPBM 139900-1, BPBM
140068-76, BPBM 143053-7); south side of Mt. Orangi
(Station 325) at 850 ft. elevation under stones (15
specimens, BPBM 139938-9).
Remarks. — There was comparatively little size
and shape variation in local populations (table
LXXXIX). The few recorded differences probably
reflect selection from the very large set of this species
in the Bishop Museum. The 1,285 specimens of the
nominate race represented the second largest sample
available for a species. Only for Australdonta degagei
(Garrett) was there a greater number of specimens.
Only part of the Orangia cookei adults were mea-
sured. While a large part of the nearly 1,300 specimens
were juvenile, discussions of the ribbing and size
variations are based on measurements of about 110
specimens, perhaps one-third of the adult specimens.
SYSTEMATIC REVIEW
285
Ribbing variation was minimal, except for Station
312 (table LXXXVIII), where there was a sharp
increase in rib count and degree of crowding. The
differences from Station 534 are statistically sig-
nificant, but since only seven of 67 specimens were
measured (with 55 df, "t" = 2.8497 for rib count and
3.2588 for rib spacing), this easily could be a strongly
biased sample. I doubt there is any biological sig-
nificance to the difference.
Most specimens were taken in the Mt. Tanga-Mt.
Tepiahu area, but 15 specimens were taken on Mt.
Orangi. Variation in the barrier structure is summa-
rized in the diagnosis above.
Description of soft parts. — Foot slightly shorter than shell
diameter, not tapering posteriorly, tail bluntly rounded. Sole
undivided, without corrugations. Pedal grooves and slime network
typical. Head projecting slightly in front of foot. Gonopore located
below and behind right ommatophore.
Body color yellow-white, without darker markings.
Mantle collar (MC) with bluntly rounded, thickened anterior
edge, no distinct lappets, grossly expanded around pneumostome,
distance from edge of collar to pneumostome large, no glandular
extension into mantle cavity. Pneumostome normal, masked by-
thickening of mantle collar. Anus continued by a slight crease
through mantle collar.
Pallial region (fig. 121a) extending apically for one-half to five-
eighths whorls. Lung roof clear in central section, scattered white
granules around and near kidney and ureter. Kidney (K) slender,
about 2.27 mm. long, posteriorly reaching hindgut, tapering an-
teriorly. Ureter (KD) arising opposite apex of kidney, not enlarging
on way to reflexed opening just anterior of rectal kidney arm
termination. Heart (H) slightly more than one-third kidney length,
angled from hindgut. Principal pulmonary vein (HV) simple,
unbranched, fading out near mantle collar. Hindgut (HG) extending
about one-sixteenth whorl above apex of pallial cavity before
deflecting downward on palatal wall, continuing one-eighth whorl
above cavity before reflexing in "S" loops.
Ovotestis (fig. 121b, G) of palmately clavate clumps of alveoli
strung along a single collecting tubule for almost three-quarters
whorl above stomach apex. Hermaphroditic duct (GD) very slender
at anterior end, grossly expanded in middle, sharply reflexed to
junction with talon. Albumen gland (GG) well developed, figured
example poorly preserved with outlines obscured. Talon (GT) very
slender, more elongated than in Endodonta, tip slightly expanded.
Prostate (DG) usually three to four rows of large acini opening into
a slender tube appressed to uterus. Head of prostate and uterus
capped with a small patch of glandular tissue, composed of finer
acini than found in albumen gland. Preservation did not allow
determination of the connections. Uterus (UT) with thin-walled,
normally expanded upper chamber occupying two-thirds of prostate
length, entering usually greatly expanded, thick-walled, lower
chamber that gradually tapers into free oviduct, internally smooth.
Vas deferens (VD) a slender continuation of prostate duct,
reflexed at penioviducal angle, entering laterally on penis between
main part and a branch of one pilaster (fig. 121c). Penial retractor
(PR) short, arising from diaphragm just above apex of pallial cavity,
fusing with a fleshy extension of penial head without sharp
differentiation. Penis (P) long, tapering to atrium and above
entrance of vas deferens, internally sculptured with two large
pilasters, one or both (usually) narrow and greatly elevated on apical
half, broadening and lowering drastically near atrium, larger of two
split with an arm cupping entrance of vas deferens (fig. 121c). Atrium
(Y) very short.
Free oviduct (UV) distinctly shorter than prostate-uterine
portion, tapering gradually, irregularly pustulose internally, differ-
entiating it from lower uterine chamber. Spermatheca (S) with
slender duct appressed to prostatic tube-uterine margin until just
before head expansion, head lying in groove between base of
albumen gland and head of expanded prostate. Vagina (V) very
short, not structurally differentiated.
Free muscle system typical. Right ommatophoral retractor
passing through penioviducal angle.
Buccal mass compact, buccal retractors not split, attaching in
U-shaped fan slightly behind midpoint of buccal mass. Esophagus
slender, arising just behind midpoint of buccal mass, extending above
level of spermathecal head. Stomach occupying slightly less than one
full whorl, typical in form. Intestine with normal S-loop pattern,
abutting on base of kidney. Hindgut only reaching parietal-palatal
margin slightly above apex of pallial cavity, following normal course
forward to anus.
Digestive and salivary glands normal in size and position.
Jaws not successfully mounted.
Radula with 5 laterals and about 13 marginals, central
approximately 8u wide and 13,u long. Marginals with basal plates
much wider than long, ectocone typically fragmented.
(Based on BPBM 139938, whole specimen 4.21 mm. in diameter
with 6'/8 whorls, other whole and partial examples.)
Orangia cookei montana, new subspecies. Fig-
ures 121d-f; 122; 123c.
Diagnosis. — Shell larger than average, diameter 3.72-4.64 mm.
(mean 4.24 mm.), with 5Vi-6lA normally coiled whorls. Apex flat or
barely elevated, lower whorls of spire descending more rapidly, last
whorl slightly deflected below periphery, H/D ratio 0.474-0.564
(mean 0.513). Umbilicus narrowly open in juveniles, barely perforate
or closed in adults. Postnuclear sculpture of narrow, lamellate,
prominent, protractively sinuated radial ribs, 81-120 (mean 104.8) on
the body whorl, whose interstices are 2-3 times their width.
Microsculpture of fine radial riblets, four to eight between each pair
of major ribs, crossed by extremely fine and crowded spiral riblets
that are barely visible under 96 X magnification. Sutures impressed,
whorls strongly rounded above, slightly flattened laterally above
very obtusely rounded periphery, lower palatal margin less
compressed than in the nominate subspecies, umbilical margin
strongly extended inwardly. Aperture ovate, periphery strongly
rounded or at most with a very weak obtuse angulation, inclined
about 20° from shell axis. Parietal barriers 2, extending posteriorly
one-quarter whorl: upper high and bladelike, expanded and serrated
above on posterior half, with very gradual anterior descension that
accelerates in last eighth of length; 2nd parietal with posterior
portion shorter, equally elevated and expanded above, with sharp
descension to threadlike anterior portion that stops slightly short of
anterior end of 1st parietal. Columellar barrier a high crescentic
blade that twists slightly downward across top of heavy columellar
callus, reaching midway to lip margin. Palatal barriers 4, extending
posteriorly a little more than one-eighth whorl; first 3 high bladelike
lamellae, expanded and serrated above on posterior half with
progressively more gradual anterior descension and slightly more
deeply recessed within aperture; 4th palatal reduced in height,
expanded and serrated above, with very gradual anterior descension,
slightly less recessed within aperture.
The longer columellar barrier reaching halfway
across the columellar callus, much more rounded
peripheral and apertural margins, and larger parietals
and palatals combine to separate Orangia cookei
montana from the nominate subspecies. O. c. tautau-
tuensis is a smaller, higher shell with even longer
columellar and the palatal barriers greatly reduced in
size.
Description. — Shell larger than average, with 6'-i normally
coiled whorls. Apex and spire moderately and almost evenly
elevated, slightly rounded above, last whorl descending a little more
286
SOLEM: ENDODONTOID LAND SNAILS
rapidly, H/D ratio 0.564. Apical whorls 1 '«. sculpture typical.
Postnuclear whorls with narrow, high, lamellate, protractively
sinuated radial ribs, 109 on the body whorl, whose interstices are 2 -
3 times their width. Microsculpture of fine radial riblets, four to
eight between each pair of major ribs, crossed by exceedingly fine
and crowded spiral riblets. Suture impressed, whorls strongly
rounded above and on outer margins, with very faint indications of
obtuse angulation at the periphery. lower palatal wall evenly and
rather strongly rounded. Color light yellow-white, with irregular,
reddish flammulations, that become zigzagged and reduced in
prominence on shell base. Umbilicus closed by inward growth of
basal and umbilical lip areas. Aperture ovate, with very obtusely
rounded outer margins, inclined about 20° from shell axis. Apertural
barriers as outlined above in diagnosis. Height of holotype 2.47 mm.,
diameter 4.37 mm.
Holotype. — Austral Islands: Rapa Island, Station
509, east ridge of Mt. Perahu at 1,300-1,550 ft.
elevation. Collected under stones by Yoshio Kondo,
Donald Anderson, and natives on July 28, 1934. BPBM
135433.
Range. - East ridge of Mt. Perahu at 1,200-1,800
ft. elevation, Rapa Island, Austral Islands.
Paratypes. — Same as list of material.
Material. — Rapa: east ridge of Mt. Perahu (Sta-
tions 446, 451, 509, 521) at 1,200-1,800 ft. elevation (40
specimens, BPBM 135433-4, BPBM 135443, BPBM
135904, BPBM 142748, BPBM 142827-30).
Remarks. — One of the 28 measured specimens
had a 5th palatal. Otherwise there was no significant
variation in the apertural barriers. The holotype of
Orangia cookei montana is atypical in being the most
elevated specimen known. Most specimens have the
spire distinctly lower.
Specimens from Station 451 at 1,200-1,500 ft.
elevation were distinctly larger than those from
Station 509 at 1,300-1,500 ft. elevation (table
LXXXIX). With 24 df, "t" = 2.4206 for the diameter.
This is not the same pattern of variation seen in
Opanara bitridentata where material from Stations
451 and 509 is smaller than material from higher
stations. Careful study of variation in the Mt. Perahu
area would be well worthwhile.
Only a single specimen was taken above 1,550 ft.
elevation (Station 521), suggesting that montana is a
form of lower elevations on Mt. Perahu.
Description of soft parts. — Foot and tail almost completely
retracted into pallia! region, rounded behind, not tapering. Sole
undivided. Pedal grooves and slime network typical.
Body color yellow-white, without darker markings.
Mantle collar as in nominate subspecies. Pneumostome in
normal position, mantle lobes absent.
Pallial region extending apically for less than three-quarters
whorl. Lung roof with widely scattered white granules, clumped near
kidney surface. Kidney about 2.34 mm. long, same shape as in
nominate subspecies. Ureter typical. Heart about one-third kidney
length, not lying parallel to hindgut. Principal pulmonary vein
typical.
Ovotestis (tig. 121(1. (',) imbedded in digestive gland, extending
three-quarters whorls above stomach reflexion, composed of pal-
mately-clavate alveoli. Hermaphroditic duct (GD), albumen gland
(GG), and talon (GT) as in nominate subspecies. Prostate (DG) with
one to three rows of acini opening into small tube. Uterus (UT) as in
nominate subspecies.
Vas deferens (VD) typical, opening laterally into penis well
below penis apex, between arms of main pilaster (fig. 121e, f). Penial
retractor (PR) arising from diaphragm, inserting on fleshy head
extension of penis. Penis (P) about 2.11 mm. long, tapering slightly
basally, internally with two pilasters, both rounded basally,
becoming slender elevated flaps apically, larger of two split into two
lobes, smaller of which cups the vas opening (fig. 121f, DP). Atrium
(Y) very short.
Free oviduct (UV) and spermatheca (S) as in nominate
subspecies. Vagina (V) not structurally differentiated due to low
insertion of spermathecal stalk.
Free muscle system and digestive system as in O. cookei cookei.
Jaw not successfully mounted.
Radula with 6 laterals and more than 9 marginals, central about
6u wide and 10u long. Shape of teeth as in Orangia cookei cookei.
(Based on BPBM 13,5433, two whole individuals, 4.11 and 4.18
mm. in diameter, with 6+ and 61.8- whorls and several extracted
specimens.)
Orangia cookei tautautuensis, new sub-
species. Figures 122; 123d.
Diagnosis. — Shell relatively small, diameter 3.03-3.75 mm.
(mean 3.42 mm.), with 5Vs-6 normally coiled whorls. Apex and spire
strongly and evenly elevated, last whorl descending more rapidly,
H/D ratio 0.517-0.592 (mean 0.552). Umbilicus completely closed.
Postnuclear sculpture of narrow, prominent, lamellate, protractively
sinuated radial ribs, 88-114 (mean 98.3) on the body whorl, whose
interstices are about twice their width. Microsculpture of very fine
radial riblets, five to nine between each pair of major ribs, crossed by
exceedingly fine and crowded spiral riblets that are visible only
under 96 X magnification. Sutures impressed, whorls strongly
rounded above, sometimes with a weak supraperipheral sulcus
present, periphery strongly rounded, lower palatal margin flatly
rounded. Aperture ovate, sometimes with sinuated upper palatal
margin, inclined about 15° from shell axis. Parietal barriers 2,
extending posteriorly more than one-quarter whorl, to or slightly
beyond line of vision; upper high and bladelike. expanded and
serrated above on visible posterior half, with very gradual anterior
descension; 2nd with visible posterior portion equally expanded and
serrated above, sharply descending to anterior threadlike portion
which stops opposite anterior end of upper parietal. Columellar
barrier high and crescentic posteriorly, sharply descending to a raised
threadlike ridge twisting slightly downward across columellar callus
and almost reaching lip margin. Palatal barriers 4, reduced in height
compared to other subspecies, extending posteriorly almost one-
quarter whorl: lower palatal partially hidden in front view by strong
development of columellar barrier and callus, weakly elevated
posteriorly, expanded and serrated above, moderately recessed within
aperture; 2nd and 3rd palatals slightly higher posteriorly, recessed
within aperture, with extremely gradual anterior descension; 4th
palatal supraperipheral, reduced in height, equally recessed within
aperture.
The great elongation of the apertural barriers,
smaller size and proportionately greater height of the
shell at once separate Orangia cookei tautautuensis
from the other two subspecies. The easiest character
for identification is the columellar barrier nearly
reaching the lip margin.
Description. — Shell rather small, with 5"s somewhat tightly-
coiled whorls. Apex and spire strongly and evenly elevated, last
whorl descending more rapidly, H/D ratio 0.573. Apical whorls l'/i,
sculpture mostly eroded, with traces of fine radial ribbing remaining
in suture. Postnuclear sculpture of high, prominent, lamellate.
SYSTEMATIC REVIEW
287
protractively sinuated radial ribs, 114 on the body whorl, whose
interstices are about twice their width. Microsculpture of extremely
fine and crowded radial riblets, four to eight between each pair of
major ribs, with barely visible spiral riblets. Sutures impressed,
whorls strongly rounded above, with slightly compressed outer and
basal margins. Color light yellow-white with irregular, somewhat
zigzagged, reddish flammulations that become much less prominent
on shell base. Umbilicus completely closed. Aperture ovate, with
sinuated lower margins, inclined about 15° from shell axis. Apertural
barriers as described above under diagnosis except that upper
parietal broken near anterior end. Height of holotype 2.01 mm.,
diameter 3.52 mm.
Holotype. — Austral Islands: Rapa Island, Station
478, hillside northwest of Mt. Tautautu at 750 ft.
elevation. Collected under stones by Yoshio Kondo on
July 25, 1934. BPBM 143300.
Range. — Hillside northwest of Mt. Tautautu at
750 ft. elevation, Rapa Island, Austral Islands.
Paratypes. — Same as list of material.
Material. — Rapa: hillside northwest (Station 478)
of Mt. Tautautu at 750 ft. elevation (9 specimens,
BPBM 143300-2).
Remarks. — One example of Orangia cookei
tautautuensis had a 5th palatal, but no other barrier
variation was noticed.
It is quite interesting that Station 478 and its very
close neighbor, Station 477, should have produced
densely sculptured, elevated subspecies of both
Orangia cookei and Opanara areaensis. The same
variation is also seen in Opanara megomphala
megomphala, which is the high-spired, more densely
ribbed subspecies. It was found at Station 427, the
coffee plantation at Maitua and Station 477. I have no
information as to what local conditions might corre-
late with this distinctive and parallel variation in three
species.
None of this material was in good enough
condition for successful dissection.
Orangia maituatensis, new species. Figures 121g-
i; 123e.
Diagnosis. — Shell of average size, diameter 3.82-4.44 mm. (mean
4.03 mm.), with 5-6V6 normally coiled whorls. Apex and spire
moderately and almost evenly elevated, occasionally slightly
flattened above, body whorl deflected beneath periphery, H/D ratio
0.411-0.519 (mean 0.466). Umbilicus barely perforate, contained more
than 19 times in the diameter (mean of perforate shells 26.7),
frequently (20 per cent) closed. Postnuclear sculpture of high,
narrow, lamellate, protractively sinuated radial ribs, 71-89 (mean
81.1) on the body whorl, whose interstices are 2-4 times their width.
Microsculpture of very fine radial riblets, four to eight between each
pair of major ribs, crossed by very crowded and fine spiral riblets,
with a secondary sculpture of low rounded spiral cording most
clearly visible on shell base, but also occurring above periphery.
Sutures impressed, whorls flatly rounded down to prominent
supraperipheral sulcus, periphery right or obtusely angulated, weakly-
protruded, lower palatal and basal margins evenly rounded, with
inward extension of baso-columellar wall. Aperture ovate, somewhat
compressed laterally above and below weakly protruded periphery,
inclined about 20° from shell axis. Parietal barriers 2, extending
posteriorly beyond line of vision: upper thin, high, bladelike,
expanded and serrated above on posterior visible half, with
practically no anterior descension until just before termination; 2nd
parietal slightly lower posteriorly, more broadly expanded above,
with sharp anterior descension to threadlike anterior third that ends
opposite termination of upper parietal. Columellar barrier a high
bladelike ridge that sharply descends and twists slightly downwards
reaching just across apex of columellar callus. Palatal barriers 4,
extending posteriorly about three-sixteenths of a whorl, moderately
deeply recessed within aperture: 1st palatal reduced in height, a
bladelike ridge, weakly expanded and serrated above with gradual
anterior descension; 2nd palatal higher than 1st, with more gradual
anterior descension; 3rd palatal moderately reduced in height, higher
than 1st. with more gradual anterior descension and deeper
recession; 4th palatal supraperipheral in position, a raised threadlike
ridge extending nearer to apertural margin.
The much sharper angulation of the periphery,
continuation of secondary spiral cording above the
periphery, much larger and less deeply recessed palatal
barriers, lower spire, and more crowded and numerous
radial ribs differentiate Orangia maituatensis from the
otherwise quite similar O. sporadica. Orangia cookei
differs in lacking any trace of secondary spiral cording,
having a larger and more prominent columellar
barrier, is generally more elevated, and normally has
the umbilicus closed rather than being minutely
perforate.
Description. — Shell large, with 6 normally coiled whorls. Apex
and spire strongly elevated, markedly rounded above, last whorl
descending slightly more rapidly, H/D ratio 0.519. Apical whorls l'/2,
sculpture eroded. Postnuclear whorls with narrow, high, lamellate,
slightly protractively sinuated radial ribs, 82 on the body whorl,
whose interstices are 2-4 times their width. Microsculpture of fine
radial riblets, four to eight between each pair of major ribs, crossed
by extremely fine and crowded spiral riblets, with a secondary
sculpture of low. crowded, rounded spiral cords that are most
prominent on shell base, but are present in reduced prominence
above periphery of body whorl. Sutures impressed, whorls flatly
rounded down to prominent supraperipheral sulcus, periphery
slightly protruded, almost right-angled, with evenly rounded lower
palatal and basal margins. Aperture ovate, flattened laterally with
sinuated margin of periphery, inclined less than 20° from shell axis.
Parietal barriers 2, extending posteriorly to line of vision: upper a
high bladelike ridge, expanded and serrated above on posterior half,
scarcely descending anteriorly until just before termination; 2nd
parietal slightly reduced in height on posterior half, more expanded
above, sharply descending to threadlike portion that terminates
opposite anterior end of upper parietal. Columellar barrier high and
crescentic posteriorly, abruptly descending and twisting slightly-
downward to top of columellar callus. Palatal barriers 4, extending
almost three-sixteenths of a whorl: lower palatal reduced in height,
expanded and serrated above, with gradual anterior descension; 2nd
palatal distinctly higher, slightly more expanded above, a little more
deeply recessed within aperture; 3rd palatal slightly lower than 2nd,
higher than 1st, with very gradual anterior descension; 4th palatal
supraperipheral, greatly reduced in height, only weakly expanded
above, with very gradual anterior descension. Height of holotype 2.31
mm., diameter 4.44 mm.
Holotype. — Austral Islands: Rapa Island, Station
308, foot of cliff behind Maitua at 800 ft. elevation.
Collected on dead leaves by Donald Anderson and C.
Montague Cooke, Jr. on July 4, 1934. BPBM 143940.
Range. — Cliffs near Maitua and Mt. Tautautu at
700-800 ft. elevation, Rapa Island, Austral Islands.
Paratypes. — Same as list of material.
Material. — Rapa Island: foot of cliff behind
Maitua (Stations 308, 317, 429) at 700-800 ft. elevation
288
SOLEM: ENDODONTOID LAND SNAILS
(21 specimens, BPBM 143938-40, BPBM 144043-6,
BPBM 144568); foot of cliff on Mt. Tautautu (Station
477) at 800 ft. elevation (1 specimen, BPBM 144719).
Remarks. — Most of the collected material
consisted of juvenile and/or dead specimens, with only
three adult and five subadult examples. The spiral
microsculpture and peripheral angulation is more
similar to O. sporadica; the ribbing and apertural
barriers are like O. cookei. All specimens were taken in
a limited part of the Maitua area under natural
conditions. Differences from the other species are
covered in the generic discussion and diagnosis above.
Description of soft parts. — Foot slightly shorter than shell
diameter, not tapering posteriorly, tail bluntly rounded. Sole
undivided, not corrugated. Pedal grooves typical. Slime network very
weak. Head partly retracted in all available specimens.
Body color yellow-white, no darker markings.
Mantle collar with thickened edges, but no distinct lobes or
glandular extension into pallial roof. Pneumostome and anus in
normal positions.
Pallial region extending five-eighths whorl apically. Lung roof
clear except for few scattered white granules near kidney surface.
Kidney about 2.10 mm. long, a short rectal arm abutting hindgut,
tapering anteriorly. Ureter starting at apex of kidney, reflexing
basally, opening just anterior of kidney rectal arm termination.
Heart about one-third length of kidney, not parallel to hindgut.
Principal pulmonary vein narrow, fading out near mantle collar.
Hindgut reaching parietal-palatal margin about one-sixteenth whorl
above apex of pallial cavity, running forward to anus without change
in diameter.
Ovotestis (fig. 121g, G) of palmately clavate alveoli imbedded in
first whorl above stomach reflexion, lower parts faintly iridescent,
upper parts with small ova (?). Hermaphroditic duct (GD) large,
grossly expanded after first portion, surface irregularly smooth,
reflexed and narrowed before inserting on talon shaft. Albumen
gland (GG) small, composed of relatively few alveoli. Talon (GT)
with slender shaft, expanded head, leading into prostate and uterus.
Prostate (G) of one to three rows of large acini opening into narrow
tube partly buried in folds of uterus. Uterus (UT) with narrow
thinwalled upper section, lower portion broadly expanded with much
thicker walls.
Vas deferens (VD) continuation of prostate tube, reflexing from
penioviducal angle, inserting subapically on penis. Penial retractor
(PR) originating from diaphragm, inserting on fleshy extension of
penis head, rather long. Penis (P) elongated, about 3.6 mm. long,
tapering basally, internally with two major pilasters. Variously split
and elevated (figs. 121h-i), branches of lower section usually greatly
enlarged. Atrium (Y) short.
Free oviduct (UV) longer than prostate-uterus, tapering initially,
then swollen basally. Spermatheca (S) with expanded head above
apex of pallial cavity, shaft inserting on free oviduct just above
atrium. Vagina (V) very short, not structurally differentiated.
Free muscle system and digestive system typical.
•Jaw not successfully mounted.
Radula with about 6 laterals, marginals missing from mount,
central about H/i wide and ll/i long. Form of teeth as in Orangia
cookei cookci.
(Based on Hl'BM 144043-4. whole specimen 4.01 mm. in
diameter with 5 ',- whorls, several smashed and partly extracted
individuals).
Orangia sporadica, new species.
123f.
Figures 121j-k;
Diagnosis, - Shell of average size, diameter 3.65-4.28 mm. (mean
3.99 mm.), with 5'j, - H't, normally coiled whorls. Apex and spire
moderately and evenly elevated, slightly rounded above, last whorl
descending a little more rapidly, H/D ratio 0.475-0.589 (mean 0.520).
Umbilicus open in juveniles, generally closed, sometimes barely
perforate in adults. Postnuclear sculpture of high, very narrow,
lamellate, protractively sinuated radial ribs, 38-64 (mean 50.8) on the
body whorl, whose interstices are 3-5 times their width. Micro-
sculpture of very fine radial riblets, six to eleven between each pair
of major ribs, crossed by barely visible, extremely crowded spiral
riblets, with a secondary sculpture of low, rounded, rather crowded
spiral cords developed below periphery of body whorl. Sutures
impressed, whorls strongly rounded above right or obtusely an-
gulated periphery, slightly compressed laterally on lower palatal
wall, with inward extended baso-columellar margin. A weak to
moderate supraperipheral sulcus present. Aperture ovate, slightly
compressed laterally below periphery, inclined about 20° from shell
axis. Parietal barriers 2, extending posteriorly beyond line of vision:
upper a very high, bladelike ridge, expanded and serrated above on
posterior visible half, with extremely gradual anterior descension
until just before anterior end; 2nd parietal equally high and
expanded above on visible posterior quarter, sharply descending
anteriorly to low threadlike trace that terminates opposite anterior
end of upper parietal. Columellar barrier a low, deeply recessed
crescentic ridge, that stops posterior to apex of heavy columellar
callus. Palatal barriers low, generally 4, sometimes 5 (13 per cent) or
rarely 6 - 8 (5 per cent), extending posteriorly about three-sixteenths
of a whorl, deeply recessed within aperture: lower palatal basal in
position, little more than an elevated threadlike ridge; 2nd palatal a
high elevated ridge, weakly expanded and serrated above, with
gradual anterior descension; 3rd palatal subperipheral, equal in size
to 1st, slightly more deeply recessed within aperture; 4th palatal
supraperipheral, greatly reduced in height, a low threadlike ridge.
Additional palatals, when present, inserted between various pairs.
The presence of secondary spiral cording below
the periphery, the very widely spaced and few (38-64)
radial ribs, and very long parietal barriers effectively
separate Orangia sporadica from the closely related
O. cookei. O. maituatuensis is very similar in size and
shape, differing most obviously by its much more
numerous (71-89) radial ribs, lower spire (mean H/D
ratio 0.466), angulated periphery, and shorter, much
higher palatal barriers.
Description. — Shell relatively large, with 6'j normally coiled
whorls. Apex and spire strongly and evenly elevated, slightly rounded
above, last whorl descending distinctly more rapidly, H/D ratio
0.582. Apical whorls I'i, sculpture of radial riblets that are
interspersed with two or three finer microradial riblets, crossed by
slightly finer and about equally spaced spiral riblets. Postnuclear
whorls with very narrow, high, flammulate, protractively sinuated
radial ribs, 56 on the body whorl, whose interstices are 4-5 times
their width. Microsculpture of very fine radial riblets, six to eleven
between each pair of major ribs, crossed by exceedingly fine and
crowded spiral riblets. A secondary sculpture of low, rounded, rather
crowded spiral cords present on body whorl l>elow periphery. Sutures
impressed, whorls strongly rounded above, with indication of a weak
supraperipheral sulcus, periphery strongly rounded, lower palatal
margin slightly compressed laterally. Basal-umbilical margin directed
inwards, columellar wall with heavy callus. Umbilicus completely
closed. Color light yellow-white, with irregularly shaped, reddish
flammulations zigzagged both above and below shell periphery.
Aperture ovate, upper palatal margin weakly sinuated, slightly
compressed laterally below periphery, inclined about 20° from shell
axis. Parietal barriers 2, extending posteriorly beyond line of vision:
upper parietal high, thin, bladelike, weakly expanded above for
posterior visible third, with practically no anterior descension until
just before end; 2nd parietal equally high and lamellate for posterior
visible quarter, sharply descending to a low threadlike ridge that
terminates opposite anterior end of upper parietal. Columellar
barrier a high crescentic- ridge posteriorly, descending anteriorly to a
point just behind columellar callus apex. Palatal barriers 4, reduced
SYSTEMATIC REVIEW
289
in height, greatly recessed within aperture, extending posteriorly
about three-sixteenths of a whorl: lower palatal basal in position,
only slightly higher than a threadlike trace; 2nd palatal a raised
threadlike ridge, expanded and serrated above, with very gradual
anterior descension; 3rd palatal equal in height to 1st, subperipheral;
4th palatal reduced in height from 3rd, supraperipheral, only slightly
larger than 1st palatal. Height of holotype 2.34 mm., diameter 4.01
Holotype. — Austral Islands: Rapa Island, Station
340, northwest of Mt. Tautautu at 600-700 ft.
elevation. Collected under stones by C. Montague
Cooke, Jr. on July 9, 1934. BPBM 144151.
Range. — Scattered localities on Rapa Island at
600-1,800 ft. elevation, Austral Islands.
Paratypes. — Same as list of material.
Material. — Rapa Island: northwest of Mt.
Tautautu (Stations 340, 479) at 800 ft. elevation, under
stones and logs (25 specimens, BPBM 143325, BPBM
144151-3); southwest of Morongoto and Morongoto
(Stations 360, 400, 401) at 800 ft. elevation under
stones (16 specimens, BPBM 140404-6, BPBM 144251,
BPBM 144338, BPBM 144341); northeast ridge of Mt.
Mangaoa (Stations 403, 485, 527) at 800-900 ft.
elevation under stones (32 specimens, BPBM 138346-7,
BPBM 138398-9, BPBM 138401, BPBM 144382,
BPBM 144385); east ridge of Mt. Perahu (Stations
451, 452, 513) at 1,200-1,800 ft. elevation on logs (4
specimens, BPBM 135574, BPBM 142832, BPBM
142878); east Maitua, northeast of Mt. Tautautu
(Station 435) under stones (20 specimens, BPBM
142620-5); southwest of Anatauri Bay (Station 333) at
650-750 ft. under stones (2 specimens, BPBM 138545);
slopes of Mt. Koara (Station 357) at 800 ft. in forest
under stones (3 specimens, BPBM 142519-20).
Remarks. — Only 23 of the 102 specimens were
adult or gerontic. More than any other Rapan species
for which a number of specimens were available,
Orangia sporadica was taken only in limited quan-
tities at widely scattered localities (fig. 117). Other
species such as Ruatara oparica, Opanara areaensis,
and Rhysoconcha atanuiensis were as widely dis-
tributed, but each had one or more areas of local
abundance. The name sporadica refers to its scattered
distribution.
The minor variation in diameter and H/D ratio
(table LXXXIX) probably is not significant in view of
the limited numbers available for study. Of 40
measured examples, seven had 5 palatals, one had 6,
and one had 8. Otherwise there was no apertural
barrier variation. The rather high number of specimens
with additional palatals and the great height reduction
of the palatals suggests a variational trend paralleling
that found in Oparana where multiplication of palatal
lamellar traces is common.
Description of soft parts. — Only smashed whole or fragmenta.ry
extracted specimens were available. Drawings were not prepared of
the pallial region or genitalia, except for part of the penial region
(fig. 121j). Only differences from other Orangia are noted below.
Penis (P) about 2.30 mm. long, more compacted than in other
Orangia, pilasters (fig. 121k, PP) shorter, broader, less elevated, and
with shorter lamellar portion, fleshy head of penis less developed
than in O. cookei, penial retractor (PR) slenderer and larger.
Entrance of vas deferens (VD) in same position.
Other aspects of anatomy showed no differences from structures
seen in O. cookei, so far as they could be observed.
(Based on BPBM 140404, two smashed, and several fragmentary
examples.)
Genus Australdonta, new genus
Endodontidae with typical apical sculpture, secondary micro-
sculpture (fig. 124) of spiral grooves (except possibly pharcata),
major radial ribs moderately to widely spaced, crowded only in
pharcata and ectopia. Apex and spire weakly (ectopia, pseudplanu-
lata) to strongly (tapina, yoshii) elevated, last whorl descending
slightly to much more rapidly. Supraperipheral sulcus present in all
but rimatarana, degagei, pharcata, and ectopia; subperipheral
sulcus present in ectopia, tapina, yoshii, magnasulcata, and
tubuaiana. Periphery usually sharply angled or keeled, rounded only
in degagei. Whorls about 5'/2, reduced in pseudplanulata, increased
in raivavaeana. Umbilicus widely open in pharcata and ectopia;
moderately open and slightly to moderately decoiling in other
species. Parietal barriers generally 3 or 4, extending posteriorly three-
sixteenths to more than one-quarter whorl, reduced to 2 in pharcata,
many threadlike traces in radieUa and a single faint trace in ectopia.
Columellar wall without barrier except in raivavaeana and
rarely in pseudplanulata. Palatal barriers 3 to 5, relatively long,
absent in radiella and ectopia. Penial retractor originating from
columellar muscle, inserting on fleshy extension to penis head. Vas
deferens inserting laterally on penis between two broadly rounded
and expanded pilasters that are complexly expanded and split.
Spermathecal shaft inserting on oviducal side of penioviducal angle
so that a very short and morphologically undifferentiated vagina
exists. Jaw of separate elongated plates. Radula typical.
Type species. — Australdonta raivavaeana, new
species.
The unique secondary microsculpture of spiral
grooving (fig. 124) is a fourth sculptural element that
characterizes the genus Australdonta. While secondary
spiral cording has been developed many times. (Cooke-
concha, Endodonta, Taipidon, Planudonta, Anceyo-
donta, Gambiodonta, Thaumatodon, Aaadonta,
Zyzzyxdonta), no other Pacific Island Endodontidae
have the spiral grooving. Under 10-40 X magnification,
usually only the major ribs and spiral grooves are
clearly visible, but under 80-100 X inspection the
complex nature of the sculpture can be recognized.
The sculpture is least developed in A. pseudplanulata,
most developed in the larger species. Australdonta
pharcata appears anomalous (fig. 137a-b) since its
sculpture can be interpreted as either very strong
grooving or development of secondary spiral cording.
The specimens are too worn for resolution of this
uncertainty. Other generic level differences concern
the presence of a fleshy extension to the penis head,
the very broad and complex folding of the penial
pilasters, and the presence of a short, internally
undifferentiated vaginal region caused by the higher
insertion of the spermathecal shaft.
The genus most apt to be confused with Austral-
donta on the basis of general similarities is the Rapa
290
SOLEM: ENDODONTOID LAND SNAILS
FIG. 124. Microsculpture of Australdonta raivavaeana, new species. BPBM 116146, greatly enlarged. (MM).
Island Orangia. The angled periphery, large size,
supraperipheral sulcus, and secondary spiral cording of
the genus give a general appearance very close to that
of Australdonta. Orangia differs in its closed umbil-
icus, only 2 parietals, high penial pilasters, and the
secondary sculpture of spiral cording rather than spiral
grooves. The origin of Orangia is from the Rapan
Opanara, while Australdonta is a local development
from Minidonta.
The smaller, more generalized species of Austral-
donta, A. pseudplanulata and A. rimatarana, differ
from the larger Austral Island Minidonta, M. plan-
ulata, M. anatonuana, and M. haplaenopla, not only
in their peculiar sculpture, but in their much wider
and regularly decoiling umbilici, much more depressed
shape (planulata more nearly intermediate), distinct
angulation to the periphery (only M. anatonuana has
an angled periphery), reduced barrier size, and shorter
parietals. The structural gap between Australdonta
and Minidonta is significant and involves alteration of
several character complexes. Unlike the Minidonta-
Anceyodonta shift on Mangareva, there are no species
known whose generic assignment requires subjective or
arbitrary judgment. Besides the sculptural change,
umbilical widening, and spire depression, shortening
and lowering of apertural barrier size, plus increase in
peripheral angulation are the relatively minor shifts in
shell structure needed for Australdonta to evolve from
stock having the characteristics of extant Austral
Island Minidonta. None of the latter have been
dissected, so anatomical comparisons cannot be made.
Previous collections of Australdonta were made
by Hugh Cuming in 1828 and by Charles De Gage on
Rurutu sometime shortly before 1879 (see Garrett,
1879). Only three species level forms were taken, A.
radiella radiella, A. radiella rurutuensis, and A.
degagei. A. r. rurutuensis was not found by members
of the Mangarevan Expedition despite extensive collec-
tions on Rurutu. Possibly the locality is in error, but
Garrett was so careful in regard to data that I have
accepted his record. All other material was gathered in
1934 during the Mangarevan Expedition.
Within Australdonta there are certain clear
patterns of variation. Size increase results in stronger
peripheral angulation and sulci development. Except
for A. pseudplanulata, the larger species are more
depressed and have a flatter spire (table XC). None of
the above are exceptional changes.
Ribbing character is relatively uniform in most
species. Only A. ectopia and A. pharcata have greatly
reduced major ribs that are very crowded. A. magna-
sulcata has the individual ribs significantly thickened.
A. yoshii has the ribs quite widely spaced and reduced
in number. There is almost equal spacing in the larger
species, A. radiella, and the largest species, A.
raivavaeana and A. tubuaiana, have only slightly
more crowded ribbing. Since rib spacing normally
increases with size, the similarity of rib spacing
numbers, 7.44 in tubuaiana and 6.02-6.35 in radiella
and yoshii, must be viewed in relation to the much
greater size of the first mentioned species. Most species
have 5 to 12 microradials between each pair of major
ribs. The number is reduced to between four and six
only in A. pseudplanulata and A. degagei. Despite the
wide spacing of the major ribs in A. yoshii, there is no
increase in the number of microradials indicating that
col
col
tol
in I
U
ml
O
o|
col
e-l
col
o
rt
in
CO
in
co'
00
in
o
CO
s
u?
CO
CM
in
CO
CO
o
•
in
m
oo
CO
s— ^
T-H
CO
to
CO
o
m
o
o
s
in
in
en
CM'
t-
csf
CM
a
<N
a
CM'
I
co
\
e-
1-
CO
•N.
CO
*
So-
\
m
oo
CO
in
oo
oo
>x
in
oo
1 —
CO
in
CM
CO
in
in
in
oo
co
in
oo
in
in
in
in
i
in
m
5-
to
oo
in
CM
00
\
CO
in
rt
ck
Q
K
o
CO
o
in"
5
CO
CO
CO
o
in"
c-
c-
co
in
to
in
m
o
in
co
in
in
to
in
in
•
o
m
o
o
CM
•<*
o
CO
o
I
CO
CO
o
v—'
c-
£
cu
B
oo
00
in
in
CM'
¥
oo
o
co'
CM
in
CM
a
co'
<N
CO
m
co'
co
•
CO
to
co'
en
m
o
•*"
CO
•*'
en
in
CM
m
o
l-H
in
53-
to
CO
CO
c-
in
<U
X
CM
co
co
<N
CO
CM'
CO
CO
•
CM
o
(N
c-
to
CM
c-
O
CM'
oo
m
CO"
to
JO
'3.
CO
CO
to
m
co" oo'
CM
C~
s
m
to
in
to'
CO
I
c-
to
oo
to
^~. 00
3
i
CO
OS
m
en
sr
CO
o
O C T3
ll|
C O E
Z co uu
to
to
oo
M
3
rt
C
e
n)
nl
I
a
Z
Q-
TD
3
i
ex
rt
n)
E
a
m
ex
n)
T3
c
'S.
2
in
co
3
•O
rt
E
U
(N
CO
00
i
2
3
a
2
c
a
a
radiella
raivavae
tubuaian
pharcata
n)
•a.
o
o
u
291
292
SOLEM: ENDODONTOID LAND SNAILS
only a spacing shift is involved in that species. In both
A. pharcata and A. ectopia the major ribs are small
and quite crowded. In the former, there are only two
to four microradials between each major pair of ribs.
The coarsened ribs of A. magnasulcata have resulted
in no change in spacing or microsculpture.
In most species the spire is comparatively elevated
and slightly rounded above. Only in A. magnasulcata,
A. pseudplanulata, and A. tubuaiana is the apex
flattened and the later whorls descending relatively
rapidly. Both A. pharcata and A. ectopia have weakly
and evenly elevated spires. In general, umbilical size
and contour correlate with spire elevation and shape
(fig. 130). The wide umbilici in the last two species
mentioned above contrast to the very narrow umbilici
of the high-spired A. degagei and A. yoshii. As normal,
the smaller species have less sharply angulated
peripheries and the largest species the greatest pe-
ripheral protrusion. Those species with strongest pe-
ripheral protrusion have the greatest development of
sulci. Prominent supra- and subperipheral sulci are
found in A. tapina, A. yoshii, A. magnasulcata, and A.
tubuaiana, but only a supraperipheral sulcus in A.
raivavaeana, A. radiella, and A. pseudplanulata. A.
ectopia has a rather weak subperipheral sulcus, but is
flattened above the periphery and thus is without a
supraperipheral sulcus.
Whorl count is rather stable, averaging about 5%,
with only A. pseudplanulata (4%) significantly re-
duced and A. raivavaeana (6) enlarged.
Apertural barrier variation involves major
modifications in only a few cases. Normally there are
either 3 or 4 major parietals, with proportions varying
between both populations and species (figs. 126, 134,
135). In A. radiella (fig. 132a-c) the parietals have split
into from four to seventeen traces, usually only
one of which is slightly more elevated. Both the
columellar and palatal walls lack any barriers in that
species. A. ectopia and A. pharcata have, respectively,
1 very reduced and 2 slightly reduced parietals. A weak
columellar barrier is normally found in A. raiva-
vaeana and rarely in A. pseudplanulata. All other
species lack the columellar. Apparently the number of
palatals normally is 5, with a reduction to 4 in A.
pseudplanulata and A. raivavaeana, 3 or 4 in A.
tubuaiana, 3 in A. pharcata, and none in A. radiella
and A. ectopia. There is considerable variation as to
palatal barrier numbers within species, but a general
pattern of reduction with increasing size is quite
obvious.
Only A. raivavaeana and degagei could be
dissected. They agree in having a fleshy extension to
the penis head, moderately subapical insertion of the
vas deferens into the penis, a short vaginal area, and
subequal, rather complexly folded pilasters that aje
larger near the apex (fig. 125). The pallial region (fig.
125c) has no peculiarities and lacks a glandular
extension of the mantle collar onto the pallial roof.
The presence of a short vaginal region and rather high
subequal pilasters effectively separate Australdonta
from any of the Rapan genera. It is not particularly
close in structure to any forms that have been
dissected.
Geographical distribution of Australdonta is
complicated only by the apparent introduction of A.
degagei from its original home on Rurutu to Rima-
tara, where it was fantastically abundant at a single
station (Station 839), and to Mauke in the Cook
Islands. Australdonta radiella is reported from both
Tubuai, where it was widely distributed and abundant,
and Rurutu, based on a record by Garrett (1879). The
latter record was not confirmed during the extensive
collections by the Mangarevan Expedition. On a
northwest to southeast line the islands Rimatara,
Rurutu, Tubuai, and Raivavae extend for about 325
miles angling across the Tropic of Capricorn. The
smallest and lowest island, Rimatara (5 sq. miles, 315
ft. elevation), had only two species, A. rimatarana and
A. degagei, taken in two days of collecting at three
stations. On Rurutu, 5.5 sq. miles and 1,300 ft.
maximum elevation, there were five species, A.
degagei, A. pseudplanulata, A. tapina, A. yoshii, and
A. magnasulcata, taken from 18 station areas over a
nine-day period. Four of the five species, all except A.
yoshii, were taken together (Station 760), while that
species occurred with A. degagei and A. magnasulcata
at Station 748. A. yoshii occurred at only the single
station, while A. magnasulcata was found in only two
areas. The other three species seemed widely dispersed
on Rurutu.
Tubuai Island, 18 sq. miles and 1,300 ft. maximum
elevation, had Australdonta radiella radiella widely
distributed; A. tubuaiana found in limited numbers
near Murivai; and the two known examples of A.
pharcata were taken near Hoopua. There were 289
radiella, 17 tubuaiana, and 2 pharcata collected from
the entire island over three days of collecting.
Raivavae Island, 12 sq. miles and 1,434 ft.
maximum elevation, had only two species, A. raiva-
vaeana and A. ectopia; the former common and
widely distributed, the latter represented by five
specimens at one station. Collections were made on
Raivavae over an 11 -day period so that the relative
paucity of Raivavaean Australdonta probably is not a
collecting artifact.
There is a quite similar and coherent growth
pattern to Australdonta that makes separation of
species from raw measurements somewhat difficult.
Hence A. degagei, A. rimatarana, and A. tapina show
overlap in measurements (table XC), but when height
and diameter (fig. 131) or H/D and D/U ratios (fig.
130) are plotted, there is obvious separation of growth
patterns. In regard to height and diameter, A. degagei
and A. rimatarana are slightly offset, but parallel in
growth; while A. tapina has a different slope to the
regression line. Separation between A. raivavaeana
CR
GG
FIG. 125. Anatomy of Australdonta: a-c, g, Australdonta raivavaeana, BPBM 147515. a, genitalia, b, interior of penial region,
c, pallial region, g, jaw; d-f, Australdonta degagei. d, genitalia, Mauke, Cook Islands, BPBM 95214, e, interior of penis, BPBM
95214, /, genitalia, Rimatara, Austral Islands. BPBM 149163. Scale lines equal 1 mm.
293
294
SOLEM: ENDODONTOID LAND SNAILS
and A. tubuaiana (fig. 136) is less dramatic, but the
qualitative differences mentioned under those species
enable identification. Variation in apertural barriers is
large (fig. 126). Although each species will have a
characteristic mean number, sufficient variation exists
that caution is required in using the key for
identifications of individual specimens.
More than in any other genus of the Endodon-
tidae, Australdonta presents a unitary set of species
with only minor combinations of differences.
KEY TO THE GENUS Australdonta
1. Palatal barriers absent 2
Palatal barriers present 4
2. Many threadlike parietal traces 3
One threadlike parietal trace.
Australdonta ectopia, new species
3. Parietal traces 4-14 (usually 7-11); Tubuai.
Australdonta radiella radiella (Pfeiffer, 1846)
Parietal traces 17; Rurutu.
Australdonta radiella rurutuensis (Garrett, 1879)
4. Mean diameter of adults above 4.30 mm 5
Mean diameter of adults under 4.00 mm 7
5. Parietal barriers 3 or more; D/U ratio about 5.25 6
Parietal barriers 2; D/U ratio about 2.75.
Australdonta pharcata, new species
6. Periphery at aperture weakly rostrate (fig. 133e): Tubuai.
Australdonta tubuaiana, new species
Periphery at aperture obtusely angled (fig. 133b); Raivavae.
Australdonta raivavaeana, new species
7. D/U ratio usually much less than 4.00 8
D/U ratio usually much more than 4.00 9
8. Periphery weakly angled; ribs fine (fig. 127d); spire and apex
almost flat Australdonta pseudplanulata, new species
Periphery of body whorl strongly rostrate; ribs very coarse (fig.
127b); apex flat, spire elevated.
Australdonta magnasulcata, new species
9. Body whorl with strongly angled periphery (fig. 129b, e) 10
Body whorl with weakly angled or rounded periphery (figs.
128b, e) 11
10. Less than 80 widely spaced ribs on body whorl.
Australdonta yoshii, new species
More than 100 rather crowded ribs on body whorl.
Australdonta tapina, new species
11. Mean H/D ratio about 0.450; mean D/U ratio about 4.63.
Australdonta rimatarana, new species
Mean H/D ratio about 0.540; mean D/U ratio about 6.50.
Australdonta degagei (Garrett, 1879)
Australdonta pseudplanulata, new species. Fig-
ure 127d-f.
Diagnosis. — Shell very small, diameter 2.55-2.88 mm. (mean
2.74 mm.), with 4%-47/s rather tightly coiled whorls. Apex and spire
flat or barely elevated, last whorl descending more rapidly, H/D
ratio 0.413-0.430 (mean 0.420). Umbilicus broadly V-shaped, slightly
and regularly decoiling, contained 3.35-3.85 (mean 3.56) times in the
diameter. Apical sculpture typical, microsculpture typical, secondary
spiral grooves very fine. Postnuclear whorls with narrow, prominent,
crowded, slightly protractively sinuated radial ribs, 80-120 on the
body whorl, whose interstices are l'/2-3 times their width. Sutures
deep, whorls strongly rounded above, slightly flattened laterally
above very weakly angled periphery, lower palatal wall evenly
rounded to sharply rounded umbilical margin. Color light yellow
horn without darker markings. Aperture subcircular, slightly
flattened laterally above very weakly angled periphery, inclined less
than 10° from shell axis. Parietal barriers 3, rarely (12.5 per cent) 4,
large, extending slightly over one-quarter whorl: upper high and
bladelike, posterior third to half slightly expanded and serrated
Panetals
Columnar
Palatals
12 3456
68
1234567
1 2
5 6 7
123456
27
1 2 3
FIG. 126. Frequency distribution of apertural barriers in
Australdonta degagei, A. raivavaeana, A. tapina, and A. tubuaiana.
above, with very sharp anterior descension; 2nd with posterior
quarter to third same as in 1st, anterior half threadlike; 3rd with
posterior portion reduced in height, anterior half a weaker threadlike
ridge; 4th, when present, a threadlike ridge, equal in length to 3rd
parietal, moderately thickened and elevated posteriorly. Columellar
barrier usually absent, rarely a deeply recessed crescentic ridge
present in juveniles. Palatal barriers 3 (25 per cent) to 4 (75 per
cent), prominent, extending more than one-eighth whorl: lower basal
in position, slightly recessed, a long curved lamellar ridge with top
edge of posterior portion flat; 2nd longer, higher, with more gradual
anterior descension; 3rd higher, longer, with very gradual anterior
descension, less deeply recessed; 4th, when present, a supraperipher-
al, V-shaped or a raised lamellar ridge, distinctly more deeply
recessed and shorter than 3rd.
The small size, very deep sutures, fine micro-
sculpture, and very weakly angled periphery combine
with the wide umbilicus to separate Australdonta
pseudplanulata from other members of the genus.
Both A. degagei and A. rimatarana are larger, have
narrower umbilici, more elevated spire and distinct
color flammulations.
Description. — Shell very small, with 4% rather tightly coiled
whorls. Apex slightly depressed, spire flat, last part of body whorl
descending quite rapidly, H/D ratio 0.414. Apical whorls 1%,
sculpture partly eroded, in spots widely separated radial ribs with
finer microradials and microspirals clearly visible. Postnuclear whorls
with narrow, prominent, crowded, slightly protractively sinuated
radial ribs, 118 on the body whorl, whose interstices are l'/2-3 times
their width. Microsculpture very fine, of crowded radial riblets,
def
FIG. 127. a-c, Australdonta magnasulcata, new species. Station 760, Mato Naa, Rurutu, Austral Islands. Holotype. BPBM 148291; d-f,
Australdonta pseudplanulata , new species. Station 754, Mato Naa, Rurutu, Austral Islands. Holotype BPBM 148204. Scale lines equal 1 mm.
Microsculpture omitted in all figures, (a-c, SG; d-f, MM).
295
296
SOLEM: ENDODONTOID LAND SNAILS
barely visible spiral microriblets, and weak, irregularly spaced spiral
grooves. Sutures deep, whorls strongly rounded above, flattened
laterally above weakly angled periphery-. Lower palatal wall evenly
rounded to baso-columellar margin, umbilical wall very strongly
rounded. Color light yellow horn, without any darker markings.
Umbilicus widely open, broadly U-shaped, regularly decoiling,
contained 3.35 times in the diameter. Aperture subcircular, flattened
laterally above periphery, inclined about 10° from shell axis. Parietal
barriers 3, large, extending slightly more than one-quarter whorl:
upper a high lamellar blade, posterior third slightly expanded and
serrated above, anterior part broken; 2nd with posterior quarter
elevated to same height as 1st, expanded above, anterior half
threadlike; 3rd parietal with posterior third very reduced in height,
anterior half a very faint threadlike trace. No columellar barrier.
Palatal barriers 4, large, extending about one-eighth whorl: lower
basal in position, a high lamellar ridge, slightly recessed, with gradual
anterior descension; 2nd longer, very slightly higher, with more
gradual anterior descension; 3rd a higher, longer bladelike lamella,
less deeply recessed, with very gradual anterior descension; 4th
supraperipheral, a rather short, low lamellar ridge, deeply recessed
within aperture. Height of holotype 1.19 mm., diameter 2.86 mm.
Holotype. — Austral Islands: Rurutu Island,
Station 754, near cliff of Mato Naa at 200 ft. elevation
under ironwood trash. Collected by C. M. Cooke, Jr.,
on August 25, 1934. BPBM 148204.
Range. — Rurutu Island, Austral Islands.
Paratypes. — Same as list of material.
Material. — Rurutu: vicinity of Mato Naa
(Stations 754, 760) at 5-200 ft. elevation (9 specimens,
BPBM 148204, BPBM 148289); north of Avera
(Station 805), 50-100 ft. inland at 5-30 ft. elevation (3
specimens, BPBM 148840); north of Hauti (Station
786) at 40-75 ft. elevation (3 specimens, BPBM
148630).
Remarks. — Of the six nearly adult shells, four
had the normal complement of 4 palatals, while the
two adult shells from near Hauti had only 3 palatals,
with the lower one absent. One juvenile from Station
760 had 4 parietals and 5 palatals, although the rest of
the set had the normal complement of 3 parietals and
4 palatals.
Australdonta pseudplanulata is by far the small-
est species of the genus and appears to be the most
generalized in structure. Only under very high mag-
nification is the spiral microsculpture visible. Whether
this is a secondary result of rib crowding or representa-
tive of a primitive sculptural state is unknown. The
relatively deep recession of the palatal barriers, deep
sutures, and nearly flat spire are quite different from
the situation observed in the other Australdonta with
typical barriers.
At first glance this species seems to be an analog
of the Raivavae Island Minidonta planulata, hence its
specific name pseudplanulata.
Australdonta rimatarana, new species. Figure
128d-f.
Diagnosis. — Shell much smaller than average, diameter 2.90-
3.22 mm. (mean 3.08 mm.), with 47/s - 5% rather tightly coiled whorls.
Apex and spire slightly elevated, lower whorls descending distinctly
more rapidly, H/D ratio 0.410-0.479 (mean 0.445). Umbilicus
relatively open, broadly U-shaped, last whorl decoiling more rapidly,
contained 4.00-5.87 times (mean 4.63) in the diameter. Apical and
microsculpture typical, secondary spiral grooving prominent.
Postnuclear whorls with thin, prominent, protractively sinuated
radial ribs, 104-127 (mean 115.7) on the body whorl, whose interstices
are 3-4 times their width. Sutures deeply impressed, whorls strongly
rounded above, curving down to very slightly angled periphery, lower
palatal margin evenly rounded, slightly compressed. Umbilical
margin strongly rounded. Aperture ovate, periphery weakly angled,
inclined about 15° from shell axis. Parietal barriers 3, prominent,
extending posteriorly about three-sixteenths of a whorl: upper with
posterior third serrated above, descending slightly, then rapidly at
end of barrier; 2nd parietal with equally high posterior third,
anterior half a high, threadlike ridge; 3rd palatal reduced in height
with slightly longer threadlike portion. Columellar barrier absent.
Palatal barriers 5, rather small, extending about one-eighth whorl:
lower a short recessed ridge with gradual anterior descension; 2nd,
3rd, and 4th higher, longer, with gradual anterior descension, more
deeply recessed, upper edge flat; 5th a V-shaped or weakly lamellar,
deeply recessed ridge, slightly shorter than 4th.
The much smaller palatals, shorter parietals, less
crowded sculpture, and only faintly angled periphery
easily separate A. rimatarana from the larger A.
tapina. A. degagei is similar in size and form, but has
a much narrower umbilicus, higher spire and longer
barriers.
Description. — Shell rather small with 5 normally coiled whorls.
Apex and early spire flat, lower whorls descending progressively more
rapidly, H/D ratio 0.462. Apical whorls with fine, widely spaced
radial ribs, a microsculpture of coequal radials and spirals barely
visible under 96 X magnification. Radials becoming more crowded
near end of apex. Postnuclear whorls with prominent, rounded,
protractively sinuated radial ribs, 127 on the body whorl, whose
interstices are 2-4 times their width. Microsculpture of fine
radial riblets, three to eight between each pair of major ribs,
extremely fine microspirals, and irregularly spaced, prominent spiral
grooves. Sutures deep, whorls strongly rounded, then curving down
to very weakly angled periphery, evenly rounded lower palatal wall,
and strongly rounded umbilical margin. No supra- or subperipheral
sulci. Color light yellow horn, with rather broad, irregular, reddish
flammulations that fade out on shell base. Umbilicus broadly U-
shaped, last whorl decoiling more rapidly, contained 4.46 times in the
diameter. Aperture ovate, periphery very weakly angled, inclined
about 15° from shell axis. Parietal barriers 3, extending about three
sixteenths of a whorl: upper high and lamellate with posterior half
slightly expanded and minutely serrated above, then angling
gradually to sharp anterior descension; 2nd parietal with threadlike
anterior third, posterior third as in upper tooth; 3rd parietal with
proportionately longer threadlike portion and lamellate posterior
reduced in height. No columellar barrier. Palatal barriers 5,
prominent, extending about one-eighth whorl: lower baso-columellar
in position, short, lower than 2nd, rather deeply recessed, with rather
sharp anterior descension; 2nd and 3rd high, deeply thickened and
weakly serrated on top, longer than 1st, with more gradual anterior
descension, a little more deeply recessed, thin lamellar blades; 4th
reduced in height from 3rd, much more gradual anterior descension,
weakly expanded and serrated above; 5th supraperipheral, deeply
recessed, a low, long lamellar ridge. Height of holotype 1.38 mm.,
diameter 3.22 mm.
Holotype. — Austral Islands: Rimatara, Station
837, 400 yd. northeast of Anapoto, at 35 ft. elevation.
Collected by Yoshio Kondo and Donald Anderson on
September 5, 1934. BPBM 149363.
Range. — Anapoto, Rimatara Island, Austral
Islands.
Paratypes. — Same as list of material.
a-f
FlG. 128. a-c, Australdonta degagei (Garrett). Rurutu, Austral Islands. Lectotype. BPBM 1002; d-f, Australdonta rimatararw, new
species. Station 837, Anapoto, Rimatara, Austral Islands. Holotype. BPBM 149363. Microsculpture omitted from all figures except for
microradials in b. Scale lines equal 1 mm. (a-c, MM; d-f, SG).
297
SOLEM: ENDODONTOID LAND SNAILS
Material. — Rimatara: vicinity of Anapoto (Sta-
tions 829, 837) at 20-50 ft. elevation (12 specimens,
BPBM 149363-4, BPBM 149096).
Remarks. — While there is considerable overlap in
basic measurements between A. rimatarana and A.
degagei, the pattern of growth is noticeably different.
When the H/D and D/U ratios are plotted (fig. 130),
there is clear and obvious separation. Plotting of the
height and diameter (fig. 131) shows the relatively
more depressed shape of A. rimatarana. The greater
angulation of the periphery and generally wider
umbilicus of the latter will separate most individuals,
but the similarities are many. Only a few specimens
from the one area of Rimatara were obtained.
Australdonta degagei (Garrett, 1879). Figures
125d-f; 128a-c.
Pitys De Gagei Garrett, 1879, Proc. Acad. Nat. Sci., Philadelphia,
1879, p. 18 — Rurutu, Austral Islands (Charles De Gage!).
Helix (Endodonta) De Gagei (Garrett), Tryon, 1887, Man.
Conchol, (2), 3, p. 65.
Endodonta (Thaumatodon) degagei (Garrett), Pilsbry, 1893, Man.
Conchol., (2), 9, p. 27.
Diagnosis. — Shell larger than average, diameter 2.86-3.52 mm.
(mean 3.23 mm.), with 5Vs • 614 rather tightly coiled whorls. Apex flat
or slightly elevated, later whorls descending progressively more
rapidly, H/D ratio 0.467-0.644 (mean 0.540). Umbilicus quite narrow,
U-shaped, only slightly decoiling, contained 4.86-8.50 times (mean
6.55) in the diameter. Apical and microsculpture typical, spiral
grooving prominent. Postnuclear whorls with low, narrow, protrac-
tively sinuated radial ribs, 83-140 (mean 110.3) on the body whorl,
whose interstices are 4-6 times their width, usually becoming very
crowded and indistinct on last part of body whorl. Sutures
prominently impressed, whorls slightly compressed and evenly
rounded laterally above and below obtusely angled periphery.
Umbilical margin strongly and evenly rounded. Aperture ovate,
slightly compressed laterally above and below barely angled
periphery, inclined about 15° from shell axis. Parietal wall usually
with 3 (75.0 per cent) or 4 (24.3 per cent), rarely 1 or 5 barriers,
extending less than one-quarter whorl: upper high, bladelike, weakly
serrated above posteriorly, with long and gradual anterior descen-
sion; 2nd equally high for posterior third, serrated above, then
descending to a threadlike ridge for anterior half; 3rd markedly
reduced in height for posterior elevated portion, anterior two-thirds
threadlike, occasionally absent; 4th and 5th parietals, when present,
deeply recessed threadlike traces along posterior half of other
parietals. No columellar barrier. Palatal wall usually with 5 (93.6 per
cent), rarely 4 (3.5 per cent), very rarely only 1 or 3 barriers,
extending about one-eighth whorl: 1st at baso-columellar margin,
rounded, a V-shaped ridge only slightly recessed; 2nd, 3rd, and 4th,
higher, progressively longer, more deeply recessed and with more
gradual anterior descension, 4th slightly lower; 5th, when present, a
recessed V-shaped or threadlike ridge above periphery, relatively
short.
The smaller size, only slightly angled periphery,
and usually 5 palatal barriers effectively separate
Australdonta degagei from A. tubuaiana and A.
raivavaeana. A. tapina is larger (mean diameter 3.51
mm.), more depressed (mean H/D ratio 0.461), and
sharply angulated with a protruded periphery and
distinct sub- and supraperipheral sulci. A. yoshii has
much more widely spaced ribbing, and a sharply
angulated, weakly protruded periphery. A. rimatarana
is the most closely related species, but has shorter,
higher barriers, a more depressed form (mean H/D
ratio 0.445), wider umbilicus (mean D/U ratio 4.63),
and fewer whorls (4% - 5%).
Description. — Shell of average size with slightly less than 5%
normally coiled whorls. Apex and early spire flat, later whorls
descending progressively more rapidly, H/D ratio 0.570. Apical
whorls l'/2, sculpture of fine radial ribs interspersed with much finer
radial riblets visible in suture. Postnuclear whorls with prominent,
rounded, somewhat protractively sinuated radial ribs, whose inter-
stices are 3-4 times their width, becoming highly irregular on last half
of body whorl. Microsculpture of very fine crowded radial riblets
crossed by much finer and more crowded spiral riblets, with a
secondary sculpture of irregularly spaced, prominent spiral grooves
developed. Sutures moderately impressed, whorls slightly flattened
laterally below periphery and on basal margin. Periphery of body
whorl very weakly angulated. Color light yellow horn with light,
somewhat irregular, reddish flammulations. Umbilicus quite narrow,
U-shaped, very slightly decoiling, contained 7.14 times in the
diameter. Aperture subovate with evenly rounded margins, inclined
about 20° from shell axis. Parietal barriers 3, extending posteriorly
one-quarter whorl: upper parietal a high bladelike ridge, serrated
above on posterior half, with gradual anterior descension; 2nd
parietal equal in height and serrated posteriorly, but anterior half
low and threadlike; 3rd parietal reduced in prominence posteriorly,
anterior two-thirds low and threadlike. Columellar region without
barrier, but with a moderately heavy callus. Palatal barriers 5, low,
bladelike, extending about one-eighth whorl: lower palatal at baso-
columellar margin, rounded above, V-shaped, reaching almost to lip
edge; 2nd palatal higher, bladelike, very slightly recessed from edge,
sharper anterior descension; 3rd and 4th palatals similar to 2nd,
slightly higher, thinner, more deeply recessed, with more gradual
anterior descension; upper palatal supraperipheral, a low, threadlike,
relatively deeply recessed ridge. Height of lectotype 2.01 mm.,
diameter 3.52 mm.
Lectotype. — Austral Islands: Rurutu. Collected
by Charles de Gage. BPBM 1002, ex Andrew Garrett.
Range. — Rurutu and Rimatara, Austral Islands
and Mauke, Cook Islands.
Paratypes. - BPBM 1002.
Material. — Austral Islands: Rimatara (25 speci-
mens, BPBM 53479); Southwest of Amaru, 20-200 yd.
inland (Station 839) at less than 25 ft. altitude under
stones, coconut husks, and dead leaves (1,552 speci-
mens, BPBM 149163-74X, BPBM 149216).
Rurutu (7 specimens, BPBM 1002): Mato Arei,
southeast of Moerai (Stations 769, 773, 774, 775) at 5-
150 ft. elevation under stones (165 specimens,. BPBM
148420-1, BPBM 148425, BPBM 148478-9, BPBM
148502-9, BPBM 148540, BPBM 148557); Mato Naa,
bluff north of Moerai (Stations 748, 753, 754, 760, 792)
at 5-200 ft. elevation (84 specimens, BPBM 148128,
BPBM 148174, BPBM 148203, ex BPBM 148289,
BPBM 148686); north of Avera (Stations 804, 805) at
5-30 ft. elevation (23 specimens, BPBM 142215, BPBM
148839); north side of bluff north of Hauti (Station
786) at 40-75 ft. elevation on dead leaves (1 specimen,
ex BPBM 148630); north center of Moerai village
(Station 757) at 30 ft. elevation (2 specimens, BPBM
148249).
Cook Islands: Mauke, 300-500 yd. inland from
Taunganui at 40-55 ft. elevation (5 specimens, BPBM
95161, BPBM 95214, BPBM 95273).
SYSTEMATIC REVIEW
TABLE XCI. - LOCAL VARIATION IN AUSTRALDONTA
299
Name
pseudplanulata
Number of
Specimens Height
Diameter
H/D Ratio
Whorls
D/U Ratio
BPBM 148630, BPBM 148840, 5
1.15±0.032
2.74*0.062
0.420i0.0036
4 5/8
3.56+0.112
BPBM 148204, BPBM 148289
(1.06-1.23)
(2.55-2.88)
(0.413-0.430)
(4 1/2-4 7/8)
(3.35-3.85)
rimatarana
BPBM 149363, BPBM 149364, 5
1.37±0.063
3.08±0.055
0.445:0.0155
5 1/8-
4.63i0.322
BPBM 149096
(1.19-1.49)
(2. 91-3.25)
(0.410-0.479)
4 7/8-5 3/8)
(4.00-5.87)
degagei
Sta. 839 1 22
1.89±0.022
3.38:0.020
0.559±0.0058
5 7/8-
6.35±0.166
BPBM 149163-4
(1.72-2.22)
(3.21-3.54)
(0.529-0.644)
(5 1/2-6 1/8)
(5.16-8.50)
Sta. 839 2
BPBM 149164, -71 38
1.67*0.017
3. 15 1 0.021
0.532:0.0044
5 1/2+
6.68±0.120
(1.46-1.92)
(2.88-3.41)
(0.484-0.607)
(5 1/8-6 )
(4.95-8.45)
BPBM 1002 7
1.74*0.066
3.20*0.077
0.541:0.0110
5 3/8 +
6.73±0.367
Paratypes
(1.52-1.99)
(2. 95-3.51)
(0.505-0.583)
(5 1/8-5 7/8)
(5.53-8.10)
Sta. 774 3
BPBM 148502-3 11
1.53±0.024
2.89iO. 028
0.529:0.0112
5 3/8
5.45±0.193
."
(1.39-1.66)
(2. 75-3. OS)
(0.471-0.595)
(5 1/8-5 5/8)
(4.57-6.39)
Mauke 3 4
1.49±0.063
2. 91i0.098
0.50Si0.0046
5 1/4
6.07±0.190
BPBM 95161, -214, -273
(1.39-1.66)
(2.75-3.18)
(0.500-0.521)
(5-5 5/8)
(5.60-6.40)
tapina
Sta. 760 5
1.58±0.064
3.71:0.070
0.425:0.0143
5 1/2+
5.40±0.340
BPBM 148290
(1.46-1.79)
(3.44-3.84)
(0.383-0.466)
(5 1/8-6)
(4.34-6.45)
BPBM 148823, BPBM 148836-8, 21
1.56±0.019
3.46±0.032
0.452i 0.0049
5 3/8-
5.29±0.079
BPBM 148867, BPBM 149045 -6
(1.39-1.72)
(3.21-3.68)
(0.417-0.500)
(5-5 5/8)
(4.82-6.00)
yoshii
BPBM 148130 10
1.62±0.036
3.30±0.075
0.490:0.0066
5 1/4+
6.11±0.180
(1.36-1.72)
(2.91-3.61)
(0.463-0.531)
(5-5 1/2)
(5.20-7.39)
radiella radiella
Cuming material 11
2. 11± 0.053
4.10i0.07P
0.514± 0.0053
5 1/4+
5.01±0.172
SMF 165740-1, FMNH 4G510
(1.84-2.43)
(3.85-4.61)
(0.475-0.535)
(5-5 5/8)
(4.07-5.90)
FMNH 46604, BPBM 106236,
BPBM 167415
Sta. 699 5
2.15±0.082
4.07+0.111
0.529±0.0103
5 1/2
4.48±0.224
BPBM 147706
(1.92-2.32)
(3.74-4.37)
(0.508-0.565)
(5 1/4-5 7/8)
(3.90-5.29)
raivavaeana
Sta. 674 53
2.14±0.029
4.50:0.036
0.476±0.0039
6-
5.44+0.056
BPBM 147515 -16, -25, -29a
(1.82-2.68)
(4.11-5.17)
(0.420-0.540)
(5 1/4-6 1/2)
(4.27-6.50)
Sta. 577 9
BPBM 146567-8
2.19±0.044
(2.02-2.35)
4.4a±0.056
(4.24-4.74)
0.488±0.0070
(0.449-0.515)
6 1/8-
(6-6 1/2)
4.53+0.073
(4.27-4.79)
tubuaiana
BPBM 147677, -705 8
2.02±0.085
4.62±0, 134
0.437iO. 0081
5 1/2+
5.21±0.159
(1.72-2.45)
(4.17-5.10)
(0.410-0.480)
(5 1/8-6)
(4.70-6.17)
1. Gerontic 2. Adults
3. Subadult
Remarks. — Not only is Australdonta degagei one
of very few endodontid species reported from more
than one island, it is the only species known from two
archipelagoes. The Mauke, Cook Islands specimens
were slightly subadult, but compare well in size and
proportions with subadult Rurutu specimens (table
XCI), except in respect to the D/U ratio. With 13 df,
"t" = 4.2680, confirming the visual impression that
their umbilici are slightly narrower. Since the Rurutu
subadult shells had much wider umbilici than the
types or Rimatara examples, this is not a significant
difference.
Individuals of A. degagei were exceedingly abun-
dant at the one station on Rimatara, and taken
sparsely at one locality on Mauke. On Rurutu they
were found at 13 of 17 stations from which endodon-
tids were collected. While no early collections from
Rimatara or Mauke exist, I consider it probable that
the isolated colonies on these islands represent recent
human introductions rather than natural occurrences.
I do not know why this species should have been
subject to accidental human transport, but suspect
that its ecology will prove to be unusual.
300
SOLEM: ENDODONTOID LAND SNAILS
Barrier variation was less extensive than in most
other large Australdonta (fig. 126). One freak gerontic
individual had only 1 parietal and 1 palatal. One
specimen of 140 examined had a fifth parietal trace,
and three specimens had only 3 palatals. Otherwise,
there was simple variation between 4 (3.5 per cent) and
5 (93.6 per cent) palatals, and 3 (75.0 per cent) or 4
(24.3 per cent) parietals.
The availability of the large sample from Rima-
tara, 1,552 specimens, allowed making a number of
comparisons within the sample. Gerontic individuals
with greatly reduced sculpture on the last half of the
body whorl and the barriers reduced in height mostly
had been segregated as BPBM 149163. A few addition-
al gerontic individuals were found in BPBM 149164
and measured with them. Specimens from BPBM
149164 and BPBM 149171 were measured separately
(table XCI). They were adult in form, but lacked the
exaggerated barrier reduction plus sculpture crowding,
and also had less pronounced descension of the body
whorl near the aperture. The difference in whorl count
is obvious, and with 58 df, "t" = 6.9754 for height, "t"
= 7.3726 for diameter, "t" = 3.7333 for H/D ratio, and
"t" = 1.6322 for D/U ratio. The difference in D/U
ratio is not significant, but the height, diameter, and
H/D ratio differences are highly significant. The
meaning of these differences is simple. Once "adult"
size, as measured by full genital development, is
reached and the start of the gerontic shell growth
syndrome commences, size increase continues for
about three-eighths of a whorl. There is sharper
descension of the body whorl, which increases the
height by an average of 13.2 per cent, while the
diameter is increasing only 7.3 per cent. The mean
H/D ratio is raised 5.1 per cent by these growth
changes. At the same time, the apparently in-
significant change in the D/U ratio may result from
the usual slight constriction in size of the apertural
opening during gerontic growth. Rib formation be-
comes highly irregular and crowded, so that rib counts
in nearly all gerontic individuals become impossible.
The type set (BPBM 1002) contained adult and
gerontic material, thus being generally intermediate
between the two series from Station 839 on Rimatara.
In contrast, the measured specimens from Station 774
on Rurutu were distinctly subadult. Measurement of
these specimens was needed for comparison with the
subadult specimens collected by P.H. Buck on Mauke,
Cook Islands in 1929 (BPBM 95167, BPBM 95214,
BPBM 95273). They were essentially identical in
height and diameter, insignificantly different in regard
to H/D ratio ("t" = 1.0974 with 13 df) and D/U ratio
("t" = 1.8768) despite the apparently large difference
in D/U ratio.
The large size differences between the Rurutu
types collected by Garrett (BPBM 1002) and the
subadults taken by the Mangarevan Expedition
('T = 3.4591-4.3992 for height, diameter, and D/U ratio
with 16 df) are simply a factor of age and not
systematically meaningful. Since proportionately few
gerontic individuals were contained in the type set,
differences in the H/D ratios were insignificant
("£" = 0.7253). When the rapid whorl descension of
gerontic growth occurs, the H/D ratio is significantly
shifted within a population, but there is no significant
change between subadult and adult examples of A.
degagei in regard to H/D ratio.
The type specimen has a slightly more rounded
periphery than most other gerontic individuals. Allow-
ance for this should be made in comparing specimens
with the type figures.
Description of soft parts. — Foot and tail slender, rather short,
in preserved material a little less than one-half shell diameter,
sharply truncated anteriorly, very slightly tapering posteriorly. Sole
and pedal grooves typical. No caudal horn or middorsal groove.
Slime network as in A. raivavaeana. Head projecting in front of
foot. Ommatophores short, eyespots inconspicuous. Gonopore in
normal position.
Body color pale yellow-white, without darker markings.
Mantle collar and glandular extension as in A. raivavaeana.
Pneumostome and mantle lobes typical. Anus opening just within
mantle collar at a slight angle, weak groove continuing through
pneumostome.
Pallial region extending nearly three-quarters of a whorl, about
3.6 mm. long. Lung roof with narrow bands of white granules
flanking principal pulmonary vein. Kidney about 1.5 mm. long, a
short rectal lobe adjacent to hindgut, surface weakly dented by loop
of intestine. Ureter typical, opening just above termination of rectal
kidney arm. Heart short, slightly angled from hindgut, about one-
half length of kidney. Principal pulmonary vein simple, fading out
just short of weak glandular extensions of mantle collar. Hindgut
typical.
Ovotestis of palmately clavate alveoli strung along a single tube,
imbedded in digestive gland above stomach apex. Hermaphroditic
duct (GD, fig. 125f) slender at first, greatly expanded where
paralleling stomach, narrowing just before entering carrefour (X).
Albumen gland (GG) typical, poorly preserved. Talon (GT) with
expanded head and long slender shaft, merging with hermaphroditic
duct to form an unclearly differentiated carrefour. Prostate (DG) of
two to three rows of large acini opening into a narrow tube that is
appressed to uterus, but not attached to it in any way. Uterus (UT)
of two sections, lower shorter and much expanded.
Vas deferens (VD) a slender tube, slightly thicker than shaft of
spermatheca. entering penis well below attachment of penial
retractor muscle (fig. 125d). Penial retractor (PR) arising from
columellar retractor and inserting on fleshy extension of penis head.
Penis (P) about 1.3-1.5 mm. long, slightly expanded above, tapering
to junction with vagina. Internally (fig. 125e) with typically modified
two-pilaster pattern. After penis pore, both pilasters greatly enlarged,
one or both splitting, forming a pocket, then tapering down to
atrium. Atrium (Y) rather short, narrow.
Free oviduct (UV) with enlarged head, tapering to a tube several
times diameter of vas deferens. Spermatheca (S) with enlarged head
lying above pallial cavity, between albumen gland and kidney,
inserting into vagina just above its union with atrium. Vagina (V)
very short.
Free muscle system and digestive system as in Australdonta
raivavaeana.
(Based on BPBM 148502, BPBM 149163-4, BPBM 95214,
dissected adults 2.8-3.4 mm., with 5-5'/i> whorls.)
Fragmentary soft parts from one of the Mauke
collections showed no differences from the genitalia of
the Rimatara populations. Penial pilaster pattern
matched, and since preservation was better than in the
a
FlG. 129. a-c, Australdonta tapina, new species. Station 805, Avera, Rurutu, Austral Islands. Holotype. BPBM 148838; d-f, Australdonta
yoshii, new species. Station 748, Mato Naa, Rurutu, Austral Islands. Holotype. BPBM 148130. Scale lines equal 1 mm. Microsculpture omitted
except for indication of spiral grooves in d and e. (SG).
301
302
.675
.625
.575
O
nj
o .525
i
475
425
SOLEM: ENDODONTOID LAND SNAILS
jf degaget
^ nmatarana
tapina
**
*
** * V ** *
***
D
n
n
D
D
n
n
8.4
4.2 4.8 54 6.0 6.6 7.2 7.8
D/U Ratio
FIG. 130. Scatter diagram plotting H/D ratio and D/U ratio for Australdonta degagei, A. rimatarana, and A. tapina.
9.0
Rimatara examples, this dissection was figured (fig.
125e).
Australdonta tapina, new species. Figure 129a-c.
Diagnosis. — Shell of slightly less than average size, diameter
3.19-3.81 mm. (mean 3.51 mm.), with 5-6 rather loosely coiled
whorls. Apex and spire slightly to moderately elevated, lower whorls
descending a trifle more rapidly, H/D ratio 0.383-0.500 (mean 0.445).
Umbilicus narrow, U-shaped, slightly decoiling, the last whorl a little
more rapidly, contained 4.34-6.45 times (mean 5.35) in the diameter.
Apical and microsculpture typical, spiral grooving prominent.
Postnuclear whorls with narrow, prominent, crowded, strongly
protractively sinuated radial ribs, 117-156 (mean 131.8) on the body
whorl, whose interstices are 2-3 times their width. Sutures relatively
shallow, whorls flattened above weak to moderate supraperipheral
sulcus, periphery obtusely angulated, usually with noticeable subpe-
ripheral sulcus, lower palatal wall compressed and gently rounded,
umbilical margin very strongly rounded. Aperture compressedly
ovate, flattened laterally above slightly protruded periphery, gradu-
ally rounded below, inclined about 20° from shell axis. Parietal
barriers 3 (28.6 per cent) or 4 (71.4 per cent), prominent, extending
posteriorly one-quarter whorl: upper high, bladelike, serrated above
on posterior half, rather sharp anterior descension after gradual
slope; 2nd with posterior third equal in height to 1st, anterior third a
high threadlike ridge; 3rd with posterior portion shorter and reduced
in height, threadlike portion longer and lower; 4th, when present, a
threadlike trace half the length of 3rd parietal, lying along posterior
half or at most weakly elevated posteriorly and two-thirds length of
3rd parietal. No columellar barrier. Palatal barriers 5, prominent,
extending about three-sixteenths of a whorl: lower a high ridge with
moderately sharp anterior descension, lower than 2nd or 3rd; next
two palatals higher, longer, slightly more deeply recessed, with more
gradual anterior descension; 4th palatal a long, low flat-topped ridge
with very gradual anterior descension; 5th palatal a deeply recessed,
long, weak to prominent lamellar ridge.
The much more crowded ribs, larger and longer
barriers, and more sharply angulated periphery easily
separate A. tapina from A. yoshii. The smaller A.
rimatarana has much smaller barriers and a less
angulated periphery.
Description. — Shell of average size with 5' i> rather loosely coiled
whorls. Apex flat, postnuclear whorls descending slightly, H/D ratio
0.417. Apical whorls 1%, sculpture partly eroded, traces of fine radial
ribs, two or three microradials in between, and a very fine
microspiral reticulation visible in the sutures. Postnuclear whorls
with narrow, prominent, strongly protractively sinuated radial ribs,
129 on the body whorl, whose interstices are 2-3 times their width.
Microsculpture of fine radial riblets, six to eight between each pair of
major ribs, barely visible spiral riblets, and rather widely and
irregularly spaced spiral grooves. Microsculpture finer than in most
other species of Australdonta. Sutures rather shallow, whorls flatly
rounded to weak supraperipheral sulcus, periphery nearly right
angled, a weak subperipheral sulcus, then evenly rounded lower
palatal wall to very strongly rounded umbilical margin. Color light
yellow-white with widely spaced, irregularly shaped, reddish mark-
ings that fade out below periphery. Umbilicus narrow, U-shaped, last
whorl decoiling a little more rapidly, contained 5.40 times in the
diameter. Aperture compressedly ovate, somewhat flattened above
and below slightly rostrate periphery, inclined about 20° from shell
axis. Parietal barriers 4, extending about one-quarter whorl: upper
SYSTEMATIC REVIEW
303
2.3
2.1
1.9
S 17
1.5
1.3
degagei
nmatarana
tapma
2.5 2.7 2.9 3.1 3.3 3.5 3.7
Diameter in mm.
FIG. 131. Scatter diagram and regression lines for height and diameter in Australdonta degagei, A. nmatarana, and A. tapina.
3.9
high, bladelike, posterior half minutely serrated on top, gradually
sloping to anterior margin; 2nd only slightly reduced in height for
posterior elevated third, anterior third a high threadlike ridge; 3rd
with posterior portion reduced in height and length, threadlike
portion lower and longer; 4th parietal a threadlike ridge, elevated
slightly posteriorly, only two-thirds length of 3rd parietal. No
columellar barrier. Palatal barriers 5, extending three-sixteenths of a
whorl, quite prominent: lower a slightly recessed ridge with fairly
sharp anterior descension, lower than 2nd barrier; 2nd and 3rd
higher, a little more deeply recessed, with much more gradual
anterior descension; 4th equal in height to 1st with very gradual
anterior descension; 5th palatal supraperipheral, a high ridge slightly
lower than 4th palatal, deeply recessed. Height of holotype 1.48 mm.,
diameter 3.56 mm.
Holotype. — Austral Islands: Rurutu, Station 805,
hillside north of Avera, 50-100 ft. inland, at 5-30 ft.
elevation. Collected on a Makatea cliff by Yoshio
Kondo and Donald Anderson on August 31, 1934.
BPBM 148838.
Range. — Lowlands of Rurutu, Austral Islands.
Paratypes. — Same as list of material.
Material. — Rurutu: Vicinity of Avera (Stations
804, 805, 806, 822) at 2-30 ft. (69 specimens, BPBM
148823, BPBM 148836-8, BPBM 148867, BPBM
149045-6); north of cave at Mato Arapia (Station 819)
at 50 ft. elevation (17 specimens, BPBM 149011); bluff
at Mato Naa (Station 760) at 5-15 ft. elevation (19
specimens, BPBM 148290); cliff at Mato Arei (Stations
769, 775) at 5-150 ft. elevation (7 specimens, BPBM
148426, BPBM 148558).
Remarks. — Despite many similarities, Austral-
donta tapina and A. rimatarana appear to be well-
characterized and distinct species. The latter has an
obtusely rounded periphery, deeply impressed sutures,
strong spiral grooving, shorter and smaller apertural
barriers that extend more than one-eighth whorl and
more widely spaced ribbing. In contrast, A. tapina has
an acutely angulated periphery, shallow sutures,
weaker spiral grooving, long lamellar apertural barriers
that extend nearly one-quarter whorl, and very
crowded ribbing. They have very similar patterns of
growth and measurements (figs. 130, 131) with iden-
tification of the species depending on the more
qualitative differences outlined above. The very fine
microsculpture of A. tapina probably is a consequence
of the excessive rib crowding. In all other Austral-
donta, the microsculpture is much more prominent.
304
SOLEM: ENDODONTOID LAND SNAILS
Of 28 nearly adult specimens 20 have 4 parietals
and eight have only 3. As in A. raivavaeana, the
proportion of specimens with 3 parietals suggests that
possibly a simple Mendelian ratio is involved (fig. 126).
In the case of A. tapina, however, the recessive could
be responsible for the absence of the 4th parietal,
which is exactly opposite the situation observed in A.
raivavaeana. All specimens of A. tapina had 5 palatal
barriers.
Australdonta yoshii, new species. Figure 129d-f.
Diagnosis. — Shell smaller than average, diameter 2.90-3.55 mm.
(mean 3.30 mm.), with 5 - 5V& relatively loosely coiled whorls. Apex
flat, postnuclear whorls descending progressively more rapidly, H/D
ratio 0.463-0.531 (mean 0.490). Umbilicus narrow, U-shaped, slightly
decoiling, last whorl a little more rapidly, contained 5.20-7.39 times
(mean 6.11) in the diameter. Apical and microsculpture typical, spiral
grooving prominent. Postnuclear whorls with low but prominent,
narrow, very widely spaced, protractively sinuated radial ribs, 54-72
(mean 65.9) on the body whorl, whose interstices are 4-6 times their
width. Sutures shallow, whorls flatly rounded above weak suprape-
ripheral sulcus, periphery nearly right angled, very slight subperi-
pheral sulcus, compressed lower palatal wall and strongly rounded
umbilical margin. Aperture subovate, flattened laterally above
strongly angled periphery, lower margins compressed, inclined about
15° from shell axis. Parietal barriers 3, occasionally 4 (9.1 per cent),
extending posteriorly slightly more than three-sixteenths of a whorl,
reduced in height: upper an elevated lamella, serrated above on
posterior half, with gradual anterior descension; 2nd reduced in
height, posterior half elevated, anterior third threadlike; 3rd parietal
threadlike for entire length, slightly broadened, but not elevated
posteriorly or with weakly lamellar elevated posterior half; 4th
parietal, when present, a threadlike trace below 3rd parietal.
Columellar barrier absent. Palatal barriers 5, short, low, extending
less than one-eighth whorl: lower a threadlike or crescentic recessed
ridge at baso-columellar margin; 2nd and 3rd elongated, raised
lamellar blades with gradual anterior descension; 4th reduced in
height, more deeply recessed, U-shaped, or a low lamellar ridge; 5th
supraperipheral, a deeply recessed threadlike to V-shaped ridge.
The very widely spaced sculpture, reduced barrier
size, and smaller diameter easily separate Austral-
donta yoshii from A. tapina. The latter has much
finer sculpture (mean ribs 131.8), larger barriers, and is
a little larger (mean diameter 3.51 mm.). The other
species of similar size, A. rimatarana and A. degagei,
are much less sharply angulated and have finer
sculpture.
Description. — Shell of average size, with 5'/2 relatively loosely
coiled whorls. Apex flat, whorls of spire descending progressively
more rapidly, H/D ratio 0.477. Embryonic sculpture partly eroded,
traces of radial ribbing visible in suture. Lower whorls with quite low
and narrow, widely spaced, protractively sinuated radial ribs, 54 on
the body whorl, whose interstices are 5-6 times their width.
Microsculpture of exceedingly fine and numerous radial riblets, even
finer and more crowded spiral riblets, plus rather prominent,
irregularly spaced spiral grooves. Sutures quite shallow, whorls flatly
rounded to weak supraperipheral sulcus. Periphery nearly right
angled, followed by a weak subperipheral sulcus, lower palatal wall
laterally compressed, evenly rounded to strongly rounded umbilical
margin. Color light yellow-white, with prominent somewhat irregu-
lar, zigzagged, reddish flammulations, becoming narrower and more
sharply angled on base of shell, merging near or in umbilicus.
Umbilicus narrow, U-shaped, last whorl decoiling slightly more
rapidly, contained 6.06 times in the diameter. Aperture subovate,
slightly flattened above weakly rostrate periphery, inclined about 15°
from shell axis. Parietal barriers 3, small, extending slightly less than
one-quarter whorl; upper a high lamellar ridge, weakly expanded and
serrated on posterior half, with gradual descension until anterior
edge; 2nd less than half height of 1st on posterior third, anterior half
threadlike; 3rd threadlike for entire length, weakly expanded and
elevated posteriorly. No columellar barrier. Palatal barriers 5, very
low, extending less than one-eighth whorl: lower columellar-basal in
position, a short, moderately recessed lamellar ridge; 2nd and 3rd
raised lamellar ridges, much higher than 1st, with very gradual
anterior descension, moderately recessed, relatively long, with flat
upper edge; 4th a long, low, V-shaped ridge, quite deeply recessed;
5th a barely visible threadlike trace, supraperipheral, about same
length as 4th. Height of holotype 1.71 mm., diameter 3.59 mm.
Holotype. — Austral Islands: Rurutu, Station 748,
foot of cliff, Mato Naa at 250 ft. elevation. Collected
by C.M. Cooke, Jr., and Yoshio Kondo on August 25,
1934. BPBM 148130.
Range. — Known only from the type collection.
Paratypes. — Same as list of material.
Material. — Rurutu: foot of cliff, Mato Naa
(Station 748) at 250 ft. elevation (115 specimens,
BPBM 148130).
Remarks. — Only the one set of this very beautiful
and well-characterized species was found. In general
appearance and apertural barriers it is an obvious
derivation of the A. tapina and A. rimatarana series,
but differs strikingly by its very widely spaced
sculpture, sharply angled periphery, and reduced size
of the apertural barriers. The type is unusual in
having the barriers smaller than in most other
individuals and possessing the smallest number of ribs
observed on an adult specimen. It was selected as
holotype because of its excellent preservation. Only 10
individuals were clearly adult, the remainder being
either partly broken shells or obvious juveniles. Barrier
variation was minimal; one of the cleaned specimens
had a 4th parietal.
Great pleasure is taken in dedicating this species
to Dr. Yoshio Kondo of the Bernice P. Bishop
Museum, without whose friendly aid and assistance
this study never would have been started, much less
completed.
Australdonta magnasulcata, new species. Figure
127a-c.
Diagnosis. — Shell of average size, diameter 3.76 mm., with 5%
rather loosely coiled whorls. Apex flat, whorls of spire descending
progressively more rapidly, H/D ratio 0.377. Umbilicus broadly open,
V-shaped, regularly decoiling, contained 3.36 times in the diameter.
Apical and microsculpture typical. Postnuclear whorls with thick,
very prominent, crowded, protractively sinuated radial ribs. 95 on the
body whorl, whose interstices are about equal to their width. Sutures
impressed, whorls sharply rounded down to prominent supraperipher-
al sulcus. Periphery protruded into corded keel, subperipheral sulcus
prominent, lower palatal wall evenly rounded to very sharply turned
umbilical margin. Aperture ovate, with rostrate periphery, inclined
about 20° from shell axis. Parietal barriers 3 or 4, large, extending
more than one-quarter whorl: upper a high lamellar ridge, posterior
two-thirds minutely serrated above, with sharp anterior descension;
2nd with posterior half equally high, anterior third threadlike; 3rd
with posterior half distinctly lower, anterior third threadlike; 4th,
SYSTEMATIC REVIEW
305
when present, a threadlike ridge only weakly elevated posteriorly.
Columellar barrier absent. Palatal barriers 5, deeply recessed, large,
extending more than one-eighth whorl: lower baso-columellar in
position, a low lamellar ridge with gradual anterior descension; 2nd,
3rd. and 4th much higher, longer, more deeply recessed with very
gradual anterior descension, posterior third with flat upper margin;
5th a high, V-shaped, supra peripheral, deeply recessed ridge, shorter
and much lower than 4th palatal.
The rostrate periphery and very heavy ribbing of
Australdonta magnasulcata immediately separate it
from the other species of the genus. The very low spire
and widely open umbilicus are almost as distinctive.
The ribbing is very similar to that found in Libera
fratercula from the Cook Islands and some of the
Gambiodonta from Mangareva, but the micro-
sculpture of irregular spiral grooves combine with the
number and form of the apertural barriers to place
magnasulcata in Australdonta.
Description. — Shell a little larger than average, with 5% rather
loosely coiled whorls. Apex flat, postnuclear whorls descending
slightly and progressively more rapidly, H/D ratio 0.377. Apical
whorls l'/8, sculpture partly eroded, traces of fine radial and much
finer microradial riblets remaining in suture. Postnuclear whorls with
high, rounded, crowded, protractively sinuated radial ribs, 93 on
the body whorl, whose interstices are about equal to their width.
Ribs narrowing, but remaining distinct within umbilicus. Micro-
sculpture of very fine and crowded radial riblets, usually worn off on
top on major ribs, much finer and more crowded spiral riblets, and
irregularly spaced, rather prominent spiral grooves. Sutures im-
pressed, whorls sharply rounded down to deep supraperipheral
sulcus, periphery protruded into cordlike beak, subperipheral sulcus
weaker than supraperipheral, lower palatal wall flatly and evenly
rounded to very sharply turned umbilical wall. Color light yellow
horn with faint, irregular, rather widely spaced, reddish
flammulations that fade out on base of shell. Umbilicus broadly
open, V-shaped, regularly decoiling, contained 3.36 times in the
diameter. Aperture ovate, with rostrate periphery, inclined about 20°
from shell axis. Parietal barriers 4, extending one-quarter whorl,
large in size: upper a high lamellar ridge, upper edge irregularly
chipped, with gradual anterior descension; 2nd with posterior three-
fourths broken off, anterior edge threadlike; 3rd with posterior half
elevated to about two-thirds height of 1st parietal, anterior third
threadlike; 4th parietal a threadlike ridge, very low anteriorly,
slightly elevated and thickened posteriorly. No columellar barrier.
Palatal barriers 5, relatively large, extending more than one-eighth
whorl, badly broken off above: lower a deeply recessed lamellar ridge
with very gradual anterior descension, relatively low; 2nd much
higher posteriorly, longer, anterior three-fourths broken off; 3rd
equal in length to 2nd, almost entire length broken off above; 4th a
distinctly lower lamellar ridge, deeply recessed, with very gradual
anterior descension; 5th supraperipheral, V-shaped, almost as high as
4th palatal, very deeply recessed within aperture. Height of holotype
1.41 mm., diameter 3.76 mm.
Holotype. — Austral Islands: Rurutu, Station 760,
bluff at Mato Naa, 5-15 ft. elevation, about 20-30 yd.
inland. Collected by Yoshio Kondo and C. M. Cooke,
Jr., on August 26, 1934. BPBM 148291.
Range. — Rurutu Island, Austral Islands.
Paratypex. — Same as list of material.
Material. — Rurutu: bluff at Mato Naa (Station
760) about 20-30 yd. inland at 5-15 ft. elevation (4
specimens, BPBM 148131, BPBM 148291); mouth of
cave at Mato Arapia (Station 819) at 50 ft. elevation (1
specimen, BPBM 149010).
FIG. 132. a-b, Australdonta radiella radiella (Pfeiffer). Tubuai,
Austral Islands. BPBM 106236; c, Australdonta radiella rurutuensis
(Garrett). Rurutu, Austral Islands. Lectotype. BPBM 944. Scale
lines equal 1 mm. Microsculpture omitted in all figures. Drawings by
YK reproduced through the courtesy of Bernice P. Bishop Museum.
306
SOLEM: ENDODONTOID LAND SNAILS
Remarks. — The flattened shape, strongly keeled
periphery, and heavy ribbing recall many of the
Gambier and Cook Island forms rather than the
Austral Island endodontids. Only one adult and four
juveniles of this evidently very rare species were
obtained. The coarsening of the ribbing and markedly
rostrate periphery represent the extreme shell devel-
opment found in Australdonta. While A. yoshii and A.
tapina have slightly rostrate peripheries, the devel-
opment in A. magnasulcata is much greater. All
individuals were dead when collected.
Australdonta radiella radiella (Pfeiffer, 1846).
Figure 132a-b.
Helix radiella Pfeiffer, 1846, Proc. Zool. Soc. London, 1845, p. 125
— Rapa Island (error); Pfeiffer, 1848, Monog. helic. viv., 1, p.
100; Pfeiffer, 1852, Syst. Conchyl. Cab., I, 12, (2), pp. 132-133, pi.
89, figs. 12-15 (plate issued in 1850); Pfeiffer, 1852, Conchol.
Icon., Helix, pi. 112, fig. 643; Pfeiffer, 1853, Monog. Helic. viv., 3,
p. 96; Pfeiffer, 1859, Ibid., 4, p. 90; Pfeiffer, 1876, Ibid., 7, p. 162.
IHelix pardalina Deshayes, 1850, Hist. nat. moll. terr. fluv., 1, pp.
88-89, pi. 83, figs. 3-4 - Ochetaroa ( = Rurutu?); Pfeiffer, 1853,
Monog. helic. viv., 2, p. 96 — listed as a synonym of radiella
Pfeiffer, 1846.
Helicella undulata "Ferussac" Pfeiffer, 1853, Monog. helic. viv., 2,
p. 96 — nude name taken from museum specimens.
Helix (Punctum) radiella Pfeiffer, Tryon, 1887, Man. Conchol., (2),
3, p. 38, pi. 8, fig. 18 (copied from Conchol. Icon.).
Endodonta (Thaumatodon) radiella (Pfeiffer), Pilsbry, 1893, Man.
Conchol., (2), 9, pp. 26-27.
Diagnosis. — Shell large, diameter 3.59-4.61 mm. (mean 4.04
mm.), with 5'/&-5% normally coiled whorls. Apex flat, whorls of spire
descending progressively more rapidly, H/D ratio 0.468-0.565 (mean
0.517). Umbilicus moderately open, U-shaped, slightly decoiling,
contained 3.90-5.90 times (mean 4.93) in the diameter. Apical and
microsculpture typical. Postnuclear whorls with rather sharply
defined, sinuately protractive radial ribs, 67-92 (mean 78.1) on the
body whorl, whose interstices are 3-6 times their width. Sutures
prominent, whorls evenly rounded below suture to somewhat
flattened upper palatal wall, obtusely rounded periphery, evenly
rounded but slightly compressed lower palatal wall and more
strongly rounded basal and umbilical margins. A barely noticeable to
prominent, broad and .shallow supraperipheral sulcus present.
Aperture subovate, slightly to strongly compressed above periphery,
inclined about 15° from shell axis. Parietal wall with 4-14 (usually 7-
11) threadlike barriers, extending posteriorly one-quarter whorl, with
one on the upper third of the wall being a much more prominent
threadlike ridge. No columellar or palatal barriers.
The absence of any palatal or columellar barriers
immediately separates Australdonta radiella radiella
from most Australdonta. A. radiella rurutuensis
differs only in having 17 parietals and may not be
separable when more material is available, while A.
ectopia has a single parietal thread and a widely open
umbilicus. All other species have 2-5 large parietals
and prominent palatals.
Description. - Shell large, with 5V4 normally coiled whorls. Apex
slightly elevated, lower whorls descending more rapidly, H/D ratio
0.514. Apical whorls 1%, sculpture partially eroded in holotype,
paratypes with sculpture of narrow but prominent radial ribs, whose
interstices are 3-5 times their width at beginning, becoming more
crowded lower down with one secondary riblet between each major
pair for first l'/4 whorls, two secondary radial riblets on later portion.
Microspiral sculpture of fine, relatively widely spaced ribs.
Postnuclear whorls with narrow, rounded, protractively sinuated,
moderately widely spaced radial ribs, 74 on the body whorl, whose
interstices are 2-4 times their width. Microsculpture of fine but
relatively prominent radial ribs, crossed by much finer and more
crowded spiral riblets with a secondary sculpture of impressed spiral
lines most clearly seen on portions of body whorl and in umbilicus.
Sutures deep, whorls flatly rounded above, flattened laterally below
obtusely rounded periphery, basal and umbilical margins evenly
rounded. Color faint yellowish-white with narrow zigzag reddish
brown flammulations, continuing onto base of shell. Body whorl
with slight supraperipheral sulcus. Umbilicus narrowly U-shaped,
slightly but regularly decoiling, contained 4.60 times in the diameter.
Aperture subquadrangular, strongly flattened laterally above and
slightly less so below periphery, inclined about 15° from the shell
axis. Lip edge broken. Parietal wall with 8 fine, regularly spaced,
threadlike barriers, extending for almost one-quarter whorl; upper
most prominent and nearly twice as high as remaining. Height of
lectotype 2.34 mm., diameter 4.54 mm.
Lectotype. — Austral Islands: "Opara" (in error).
Collected by Hugh Cuming. BMNH 1962701/1.
Range. — Tubuai, Austral Islands.
Paratypes. — "Opara" or "Opana" ( = Rapa, error)
(10 specimens, BMNH 1962701/2-5, BPBM 106236 ex
Webb, BPBM 167415 ex Fulton, Grateloup, Pfeiffer,
SMF 165740 ex Knobbe, SMF 165741 ex Pfeiffer).
Material. — Austral Islands: Tubuai, trail south of
Murivai (Station 699) at 6-8 ft. elevation in sandy soil
(136 specimens, BPBM 147706); 100-200 yd. west of
Mataura at about 100 yd. inland (Station 696) under
Barringtonia trees (55 specimens, BPBM 147638,
BPBM 147660, BPBM 147968); south of Hoopua
about 200-300 yd. inland (Station 703) at 5 ft.
elevation (81 specimens, BPBM 147724-5); fossils
taken from walls at Taahuaia (Stations 702, 704) (11
specimens, BPBM 147719, BPBM 147741); 75 ft.
inland at Teuo (Station 707) at 3 ft. elevation (6
specimens, BPBM 147760). Rapa (error) (2 specimens,
FMNH 46510 ex Fulton, FMNH 46604 ex Gude,
Stevens).
Remarks. — Originally described as coming from
Rapa, Helix radiella is moderately common in older
collections. The Mangarevan Expedition found it on
Tubuai in subfossil deposits, but obtained no material
from Rapa. Undoubtedly, this is one of the many
locality confusions present in the Cuming collection.
According to St. John (1940, pp. 87-88), Hugh Cuming
collected on Tubuai May 5, 1828 and this may be
taken as the time when the type and paratype
specimens were obtained. Probably all specimens in old
collections labelled "Opara" or "Opana" are type lot
specimens. I have listed as paratypes only those
individuals that could be traced as coming from the
Cuming or Pfeiffer collections.
All of the Mangarevan material was collected
from subfossil deposits and the apertures were clogged
with dirt. Thirty individuals were cleaned in order to
check the parietal barriers. The extremes were 4 and
14, with considerable clustering. Ten individuals had
11 barriers, 5 had 8, and 4 had 10. Twenty-three of the
30 had 8-12, only 2 had more than 12 and 5 had 4-7.
No difference was noted between Cuming and Man-
garevan materials in respect to barrier count.
SYSTEMATIC REVIEW
307
Comparatively few specimens were clearly adult.
Of the 291 Mangarevan Expedition shells, only eight
were adult and measured. The rest were subadult or so
encrusted that no attempt at cleaning or measuring
was made. Comparison of these shells with the Cuming
material, 11 examples, showed minor differences except
in regard to rib count (table XC). With 21df1, "t" =
2.830 for the rib counts, reaching the 5 per cent
probability level that the recent shells have more ribs
than those collected by Cuming. The differences in size
and shape were small enough that no question of
difference arose and "t" was not calculated. Shells
from Station 699 had relatively wide umbilici (table
XCI), and the few adults from Stations 702 and 707
much narrower. Too few specimens are involved for
meaningful statistical analysis.
Of the other names listed in the synonymy, Helix
undulata is a nude name taken from museum
specimens while Helix pardalina may refer to the
Rurutu subspecies. No specimens of pardalina could
be located, but I have chosen to consider it a synonym
of A. r. radiella. The reference of the island name,
Ocheteroa, is obscure. Either Tubuai or Rurutu could
be intended.
Australdonta radiella rurutuensis (Garrett,
1879). Figure 132c.
Patula rurutuensis Garrett, 1879, Proc. Acad. Nat. Sci., Phila-
delphia, 1879, p. 18 - Rurutu, Austral Islands (Charles De
Gage!).
Helix (Endodonta) rurutuensis (Garrett), Tryon, 1887, Man.
Conchol., (2), 3, p. 61.
Endodonta (Thaumatodon) rurutuensis (Garrett), Pilsbry, 1893,
Man. ConchoL, (2), 9, p. 27.
Diagnosis. — The only significant difference from Australdonta
radiella radiella lies in having 17 distinguishable parietals. Shape
and sculpture fall within the limits of variation observed for the
nominate race. The diameter (3.52 mm.) is less than that of nearly
all adult A. radiella radiella, but the shell is clearly subadult and
this difference has no significance.
Description. — Shell subadult, smaller than average of nominate
race, with slightly less than 5'/s normally coiled whorls. Apex flat,
lower whorls of spire descending progressively more rapidly, H/D
ratio 0.506. Apical whorls 1%, sculpture eroded by fungus except for
traces of radial ribs in suture. Postnuclear whorls with prominent, V-
shaped, protractively sinuated radial ribs, 73 on the body whorl,
whose interstices are 3-6 times their width. Microsculpture of fine
and crowded radial ribs, crossed by very much finer and more
crowded spiral riblets. A secondary sculpture of vague, irregularly
spaced, shallow spiral grooves that are more prominent on shell base.
Sutures moderately impressed, evenly rounded below suture, whorls
slightly flattened above and below obtusely rounded periphery, basal
and umbilical margins evenly rounded. Color light yellow horn with
prominent, rather wide, zigzag, reddish flammulations, becoming
narrow and strongly protractive on shell base. Umbilicus moderately
open, U-shaped, slowly and evenly decoiling, contained 4.86 times in
the diameter. Aperture subquadrangular, flattened laterally above
and below obtusely rounded periphery, inclined about 15° from shell
axis. Parietal wall with 17 low, threadlike ridges, extending
posteriorly beyond line of vision, 3rd from top a low, rounded ridge
'Rib counts could be made on a few individuals whose broken
outer lip prevented measurement of the diameter, and one measured
example had the sculpture obscured by fungal growth, hence Ni= 13
and N2= 10 in this calculation.
nearly twice the height of the others. Columellar and palatal walls
without barriers. Height of lectotype 1.81 mm., diameter 3.52 mm.
Lectotype. — Austral Islands: Rurutu. Collected
by Andrew Garrett. BPBM 944.
Range. — Rurutu, Austral Islands.
Material. — The lectotype was the only specimen
located.
Remarks. — The original description mentions
only a single parietal, but without use of a microscope,
the very low and inconspicuous parietal threads easily
could be overlooked. In other respects, the type
description and lectotype agree.
Despite rather extensive collections made on
Rurutu during the Mangarevan Expedition, no addi-
tional material of this species was found. The
possibility exists that rurutuensis was based on an
atypical specimen of A. radiella from Tubuai. In view
of Garrett's extreme care concerning locality data, I
am retaining it as a distinct taxon. If additional
collections of subfossil material on Tubuai extend the
parietal lamellar variational range in A. radiella
radiella to include 17 barriers, then A. r. radiella and
A. r. rurutuensis should be synonymized.
Australdonta raivavaeana, new species. Figures
125a-c, g; 133a-c.
Diagnosis. — Shell very large, diameter 4.08-5.13 mm. (mean 4.50
mm.), with 5W-6'/2 normally coiled whorls. Apex and early spire
flat, rarely slightly depressed, whorls of lower spire descending
progressively more rapidly, H/D ratio 0.420-0.540 (mean 0.479).
Umbilicus narrowly U-shaped, slightly and regularly decoiling,
contained 4.00-5.50 times (mean 5.27) in the diameter. Apical and
microsculpture typical, spiral grooves prominent. Postnuclear whorls
with narrow, relatively high, protractively sinuated radial ribs, 81-148
(mean 109.4) on the body whorl, whose interstices are 2-5 times their
width. Sutures prominent, whorls flattened laterally above weak to
almost absent supraperipheral sulcus, periphery right to obtusely
angled with rounded margin, lower palatal wall evenly and gently
rounded although laterally compressed. Umbilical and basal margins
strongly rounded. Aperture subovate, flattened laterally above
periphery, inclined about 15° from shell axis. Parietal wall usually
with 3 (74.6 per cent) or 4 (22.1 per cent) barriers extending
posteriorly about three-sixteenths of a whorl, rarely (3.3 per cent)
with one to three accessory traces present: upper a high bladelike
ridge with gradual anterior descension on last sixth; 2nd with high
posterior quarter, gradual descension to about midpoint, then
threadlike anterior section; 3rd same as 2nd, only a little reduced in
height; 4th (when present) usually a threadlike trace (occasionally
with posterior eighth weakly elevated), located below and propor-
tionately closer to 3rd parietal. Columellar wall without (23 per cent)
or with a very short, threadlike ridge (77 per cent) extending less
than one-eighth whorl. Palatal wall with 4 short barriers, occasion-
ally (8.1 per cent) 1 or 2 extra present: lower a high ridge, flattened
above, with fairly sharp anterior descension, extending a short
distance back; 2nd and 3rd equal in height, longer, with more
gradual anterior descension; upper supraperipheral, a weak V-shaped
or bladelike ridge slightly shorter than 3rd barrier. Accessory traces
variously distributed between lower three barriers.
A. tubuaiana from Tubuai is nearly identical in
size and umbilical width, but has a much more sharply
angled periphery with slight subperipheral sulcus,
larger and more prominent barriers, and a lower spire
(H/D ratio 0.410-0.480). The only other Australdonta
e
FIG. 133. a-c, Australdonta raiiwaeana. new species. Station 674, Mt. Turivao, Raivavae, Austral Islands. Holotype. BPBM 147529;
d-f, Australdonta tubuaiana. new species. Station 698, Murivai, Tubuai, Austral Islands. Holotype. BPBM 147705. Scale lines equal 1
mm. Microaculpture omitted in all figures. (SG).
308
SYSTEMATIC REVIEW
309
of similar size, A. radiella, lacks any palatal barriers.
All other species are much smaller.
Description. — Shell large, with slightly more than 6 normally
coiled whorls. Apex and early spire flat, later whorls descending
progressively more rapidly, H/D ratio 0.447. Apex and upper spire
with sculpture eroded. Lower whorls with narrow, prominent,
moderately crowded, protractively sinuated radial ribs, 123 on the
body whorl, whose interstices are 3-6 times their width. Micro-
sculpture of fine radial riblets, usually eight to twelve between major
rib pairs and barely visible microspiral riblets. Secondary micro-
sculpture of irregularly spaced spiral grooves more clearly visible
than the very faint and crowded microspiral ribbing. Sutures
prominent, whorls flattened laterally above weak supra peripheral
sulcus, periphery obtusely angulated, lower palatal wall gently and
evenly rounded to strongly rounded basal margin. Color light yellow
horn with prominent, regularly spaced, zigzag, red flammulations,
narrow at periphery, widening and tending to merge in umbilicus.
Umbilicus narrow, U-shaped, slightly and regularly decoiling,
contained 4.79 times in the diameter. Aperture subovate, slightly
flattened laterally above periphery, inclined about 15° from shell
axis. Parietal barriers 3, extending about three-sixteenths of a whorl
posteriorly: upper high and bladelike with sharp anterior descension,
upper edge slightly expanded and minutely serrated on posterior
half; 2nd parietal identical for posterior quarter, gradually descend-
ing with anterior half threadlike; 3rd parietal much lower, less than
posterior one-quarter elevated and serrated, anterior two-thirds low
and threadlike. Columellar barrier absent. Palatal barriers 4, short,
moderately recessed: lower high and bladelike, with rather sharp
anterior descension; 2nd and 3rd equal in height, longer, progressive-
ly more recessed and with more gradual anterior descension; 4th
supraperipheral, a deeply recessed, low, threadlike ridge, slightly
shorter than 3rd barrier. Height of holotype 1.98 mm., diameter 4.40
mm.
Holotype. — Austral Islands: Raivavae Island,
Station 674, south cliff of Mt. Turivao at 650 ft.
elevation. Collected under clumps of Hymenolepis by
Donald Anderson and Elwood Zimmerman on August
13, 1934. BPBM 147529.
Range. — Raivavae Island, Austral Islands.
Para types. — Same as list of material.
Material. — Raivavae Island: south cliff of Mt.
Turivao (Station 674) at 650 ft. elevation (731
specimens, BPBM 147515-29); Ahuoivi Pt. (Station
622) at 5 ft. elevation under dead leaves (3 specimens,
BPBM 142174, BPBM 147097); Anatonu (Stations
633, 636, 652) at 50-150 ft. elevation (89 specimens,
BPBM 147165, BPBM 147195, BPBM 147383, BPBM
147386); pass between Mt. Hiro and Araua (Station
646) at 1,000+ ft. on ground under orange trees (1
specimen, BPBM 147266); pass between Mt. Turivao
and Mt. Muatapu (Station 662) at 550 ft. elevation on
dead pandanus leaves (1 specimen, BPBM 147449);
south cliff of Mt. Taraia (Stations 551, 577, 589) at
850-900 ft. elevation (57 specimens, BPBM 146566-8,
BPBM 146225, BPBM 146587-9).
Remarks. — Australdonta raivavaeana was quite
common in the native vegetation on Mt. Turivao and
was taken in lesser numbers alive on Mt. Taraia at 850
ft. elevation. A few scattered individuals were collected
dead or as fossils in lowland localities. Many of the
specimens from Mt. Taraia had the supraperipheral
sulcus quite strongly developed, but most individuals
Sta.
674
«_>
o>
40-
35-
30-
25'
20-
GO
o
OJ , r
-e 15-
10-
(H
Sta.
674
34 34
PR
FIG. 134. Parietal and columellar lamellae frequency variations
in two populations of Australdonta raivavaeana.
approached the more typical condition found in the
type population. In addition, the mean umbilical width
of the Taraia examples was significantly wider (table
XCI) than the Turivao examples, with 60 df, "t" =
6.4721 for D/U ratio, but only 1.2243 for H/D and
0.0426 for D. These could be considered different
subspecies in view of the two differences cited above,
but I prefer not to add another name to the literature
when the differences are so minor.
Comparatively few individuals, 66 of 882, were
adult. Time did not permit complete analysis of barrier
or rib variation within the material, but some data
were compiled. Rib counts on 24 adult examples were
bimodal, three gerontic individuals having 139, 148,
and 149 ribs, while the rest had 81-123 ribs on the body
whorl.
Barrier variation was somewhat correlated with
age, the very young individuals having only 3 parietals
and four ananeanic shells having 2 parietals. Barrier
variation is summarized in Figure 134. The ratio of
"0" to "1" columellar barriers is close to simple
Mendelian ratio. The ratio of "3" to "4" parietals
would probably be closer if the number of "3" 's was
not heavily weighed by counts of juvenile individuals.
Correlations of barrier numbers are shown in Figure
310
SOLEM: ENDODONTOID LAND SNAILS
35-
30-
§ 25-
E
1 20-
0> 1C^
1
10-
5-
0-
3PR 1C 3PR OC 4PR OC 4PR 1C
FIG. 135. Correlation of parietal and columellar lamellae in
Australdonta raivavaeana.
135. With 3 parietals the ratio of "0" to "1" columellar
is the same as in the total sample, but a dis-
proportionate number of shells with 4 parietals have a
columellar barrier. Analysis within populations showed
considerable differences (fig. 134). While the total
numbers approach the pattern of a Mendelian domi-
nant for the presence of a columellar and only 3
parietals, the actual genetic picture is probably much
more complex. If still extant, the populations on Mt.
Turivao and Mt. Taraia would warrant quantitative
sampling and attempts at cross breeding in view of the
barrier ratio variations.
Description of soft parts. — Foot long, slender, bluntly truncated
anteriorly, length slightly less than shell diameter. Tail bluntly
rounded posteriorly, only slightly tapering. Sole undivided. Pedal
grooves uniting over tail, suprapedal much weaker than pedal. No
caudal horn or middorsal groove present. Slime network most
conspicuous near visceral hump and on sides of tail. Head protruding
markedly in front of foot edge. Ommatophores typical, eyespots
relatively small. Gonopore located in normal position.
Body darkened by preservative. No distinct markings.
Mantle collar not swollen, pneumostomal opening flanked by
two small lappets, a weak nodular anterior left mantle lappet and a
larger, elongated right mantle flap. Latter on elongated ridge, much
larger than left lappet. A modest glandular extension reaches onto
lung roof. Anus (A) opening at slight angle just inside pneumostome,
a weak groove continued through mantle collar.
Pallial region (fig. 125c) extending two-thirds of a whorl
apically, about 5.9 mm. long. Lung roof with moderate to heavy
accumulation of white granules over mantle collar, flanking principal
pulmonary vein, then following sides of kidney and ureter for a short
distance. A few granules along hindgut. Kidney (K) 2.3-2.6 mm. long,
2.2 times length of heart, rectal lobe abutting on hindgut, kidney
base extending above loop of intestine. Ureter (KD) a narrow tube
arising from anterior end of kidney, opening next to hindgut. just
above anterior end of rectal kidney arm. Heart (H) lying at slight
angle to hindgut, slender. Principal pulmonary vein (HV) un-
branched, fading out just before mantle collar. Hindgut (HG) arising
about 2.5 mm. above apex of pallial cavity, only reaching parietal-
palatal margin 1.2 mm. above pallial cavity head, passing forward
normally to anus.
Ovotestis (G, fig. 125a) as in Endodonta fricki, imbedded in
digestive gland above apex of stomach, stopping far short of apex.
Ovotestis of palmately clavate alveoli, lower portion of alveoli
iridescent, upper branches in some examples with partly developed
eggs. Hermaphroditic duct (GD) with early portion convoluted and
rather slender, becoming thick and straight while running along
stomach, narrowing abruptly near end of albumen gland, passing
into carrefour (X) after a curving turn. Albumen gland (GG) typical,
extending from apex of pallial cavity to base of stomach, poorly
preserved in dissected material. Talon (GT) with slightly expanded
head and long, slender shaft. Carrefour (X) not clearly delineated in
dissected specimens. Prostate (DG) rather long, two to three rows of
large acini opening into a narrow tube closely appressed to, but
morphologically separate from, uterus. Uterus (UT) very thin walled
(hidden by prostate in Figure 125a), differentiated into narrower
upper and expanded basal section.
Vas deferens (VD) a slender tube, passing to penioviducal angle,
then narrowing, running free along penis to insert laterally just
below head of penis. Penis pore opening just below point where
pilasters merge (fig. 125b). Penial retractor (PR) arising off
columellar muscle just above union with tail fan, fusing into a fleshy
extension of penis head. Penis (P) about 3.3 mm. long, upper portion
swollen after slender neck above vas deferens insertion, tapering
down to junction with free oviduct. Internally with two narrow
pilasters uniting at apex, grossly expanded with a secondary union
just above penis pore, smooth or complexly folded on surface,
variously tapering down, merging into wall, splitting, or reappearing
in basal portion (fig. 125b). Atrium (Y) narrow, rather long.
Free oviduct (UV) with enlarged head, tapering to a tube only
twice diameter of vas deferens. Spermatheca (S) with enlarged head
lying apicad of pallial cavity, between albumen gland and kidney
apex, slender shaft passing down prostate-uterus and joining free
oviduct just above union of vagina and penis. Vagina (V) very short,
scarcely differentiated from atrium.
Free muscle system simple. Right ommatophoral retractor
passing through penioviducal angle, uniting with right rhinophoral
retractor over half way to union with tail fan. Tentacular retractors
unite laterally with tail fan well below point where buccal retractor
merges.
Buccal mass high, elongated, with distinct posterior protrusion
of the generative sac. Buccal retractors inserting in U-shaped fan
on base of mass, about one-quarter of distance from posterior end.
Esophagus arising just past midpoint, extending to about 2 mm.
above pallial cavity. Stomach extending a full whorl, taking less
than one-quarter whorl to reach parietal-palatal margin. Intestine
coiling of normal pattern, occupying less than one-quarter whorl
above pallial cavity apex.
Digestive glands and salivary glands typical, latter uniting above
esophagus.
Jaw (fig. 125g) of rectangular, slightly overlapping plates, about
12 per half row, that are weakly striate longitudinally.
Radula with formula 7-6-1-6-7. Central with median cusp
extending well in front of basal plate edge, two small ectocones.
Laterals with large mesocone, prominent ectocone, elongately
rectangular basal plate, no entocone. First marginal with shortened
basal plate, entocone developed on side of mesocone. Remaining
marginals involve rapid shift to having entocone and mesocone sub-
equal in size, ectocone (after 2nd marginal) split in two or three
cusps (often four on last), basal plates much broader than long.
(Based on BPBM 147515, dissected whole specimen 4.67 mm. in
diameter with 6Vi whorls.)
SYSTEMATIC REVIEW
311
Australdonta tubuaiana, new species. Figure
133d-f.
Diagnosis. — Shell large, diameter 4.17-5.07 mm. (mean 4.62
mm.), with 5'/6-6 rather loosely coiled whorls. Apex and early spire
flat, later whorls descending progressively more rapidly, H/D ratio
0.410-0.480 (mean 0.437). Umbilicus narrow, U-shaped, regularly and
slightly decoiling. contained 4.70-6.17 times (mean 5.21) in the
diameter. Apical and microsculpture typical. Postnuclear whorls with
low, rounded, protractively sinuated radial ribs, 95-118 (mean 108) on
the body whorl, whose interstices are l'/2-3 times their width. Sutures
shallow, whorls flattened laterally above nearly right-angled pe-
riphery, gently rounded on lower palatal margin. Weak supra- and
subperipheral sulci present. Aperture typical. Parietal barriers
usually 4, rarely 3 or 6, extending posteriorly about one-quarter
whorl: upper high and bladelike, serrated above on posterior two-
thirds with rather sharp anterior descension; 2nd and 3rd much
lower, only slightly elevated posteriorly, anterior two-thirds thread-
like, 3rd lower than 2nd; 4th barrier a low, threadlike ridge slightly
widened, but not elevated, posteriorly. No columellar barrier. Palatal
barriers 3 or 4, elongated, extending slightly more than one-eighth
whorl: lower reduced in height, a little recessed, with gradual
anterior descension; 2nd and 3rd coequal, higher than 1st, progres-
sively a little more recessed, with very gradual anterior descension;
4th palatal, when present, a threadlike or weakly V-shaped, recessed,
supraperipheral ridge.
The large size, very weakly rostrate periphery and
depressed shape are diagnostic of A. tubuaiana.
Australdonta raivavaeana is a more elevated (mean
H/D ratio 0.479) shell with less angulated periphery,
narrower major radial ribs, no subperipheral sulcus,
and shorter, higher apertural barriers. A. radiella
differs most conspicuously in lacking any palatals,
while the other Australdonta are all much smaller.
Description. — Shell large, with 5"'s rather loosely coiled whorls.
Apex and early spire flat, lower whorls descending progressively more
rapidly, H/D ratio 0.439. Apical whorls 1 f/a, sculpture eroded. Post-
nuclear whorls with prominent, rounded, rather wide, protractively
sinuated radial ribs, 98 on the body whorl, whose interstices are less
than twice their width. Microsculpture of five to nine radial riblets
between each major rib pair, a microspiral ribbing barely visible
under 96 x magnification and a secondary microspiral sculpture of
irregularly spaced spiral grooves. Sutures impressed, whorls flattened
laterally above weak supraperipheral sulcus, periphery right angled
with a weak subperipheral sulcus, evenly and gently rounded lower
palatal margin, umbilical margin strongly rounded. Color light
yellow-white with broad reddish flames that coalesce on base of
shell. Umbilicus narrow, U-shaped, slightly and regularly
decoiling, contained 6.17 times in the diameter. Aperture
compressedly ovate, periphery weakly rostrate, inclined about 20°
from shell axis. Parietal barriers 4, extending posteriorly about one-
quarter whorl, a partial accessory trace below 4th: upper parietal
high and bladelike, serrated above posteriorly, with gradual anterior
descension; 2nd and 3rd much lower, elevated posteriorly, with
anterior half threadlike; 4th parietal a threadlike ridge, weakly
broadened posteriorly. Columellar barrier absent. Palatals 4,
elongated low barriers extending about one-eighth whorl: 1st and
2nd palatals broken off above and lip edge fragmented; 3rd a high
ridge with gradual anterior descension, moderately recessed from lip
edge; 4th a recessed, V-shaped ridge, supraperipheral, much lower
than 3rd palatal. Height of holotype 2.47 mm., diameter 4.87 mm.
Holotype. — Austral Islands: Tubuai Island,
Station 698, south of Murivai at 6-8 ft. elevation.
Collected dead in sandy soil along trail by Yoshio
Kondo and Donald Anderson on August 16, 1934.
BPBM 147705.
Range. — Tubuai Island, Austral Islands.
Paratypes. - BPBM 147705, BPBM 147677-8.
Material. — All 17 specimens came from the type
locality.
Remarks. — While undoubtedly closely related to
A. raivavaeana, the differences in peripheral angula-
tion, H/D ratio, length and height of apertural
barriers, and major rib width readily distinguish the
two species. As can be seen in Figure 136, A.
tubuaiana and A. raivavaeana have slightly different
growth patterns, although there is considerable over-
lap.
Since only eight specimens were adult, data on
variation are scanty. Barrier variation is presented in
Figure 126, but the numbers are too small for any
meaningful analysis.
Australdonta pharcata, new species. Figure 137
a-c.
Diagnosis. — Shell very large, adult diameter about 4.60 mm.,
probably with 5'-2 tightly coiled whorls. Apex barely elevated, spire
flatly coiled, last whorl descending rapidly, H/D ratio about 0.430.
Umbilicus broadly V-shaped, regularly decoiling, contained 2.50-2.97
times (mean 2.74) in the diameter. Postnuclear sculpture of narrow,
crowded, strongly protractively sinuated radial ribs, probably about
200-250 ribs on the body whorl, whose interstices are about equal to
their width. Microsculpture occasionally visible as extremely fine
microreticulation, with a secondary sculpture of prominent, rounded
spiral cords (?) that are equal in size to the major radial ribs. Sutures
deep, whorls strongly rounded above and on basal margin, flattened
laterally above and below right-angled periphery, with evenly
rounded basal margin. Aperture subovate, strongly flattened later-
ally above and below protruded periphery, inclined about 20° from
shell axis. Parietal barriers 2, extending posteriorly to line of vision:
upper a very high and slender, bladelike lamella, very weakly
expanded above on posterior visible third, with gradual anterior
descension until shortly before termination; 2nd less than one-third
height of upper, anterior visible half an elevated threadlike trace,
extending anteriorly opposite end of upper parietal. Columellar wall
without barrier. Palatal wall with 3 moderately recessed barriers,
extending posteriorly almost one-quarter whorl: lower basal in
position, narrow and elevated, with gradual anterior descension; 2nd
on middle of lower palatal wall, slightly reduced in height and more
deeply recessed, a V-shaped lamellar ridge with very gradual anterior
descension; 3rd supraperipheral, very deeply recessed, a fine, raised
threadlike trace.
The reduction in number and elongation of both
parietal and palatal barriers, comparatively widely
open umbilicus, reduced radial ribbing, and very strong
secondary spiral sculpture characterize Australdonta
pharcata. The most similar species is the even more
depressed and widely umbilicated A. ectopia from
Raivavae, which has lost its palatal barriers and
retains only a single parietal trace. All other Austral-
donta have much narrower umbilici, more barriers,
higher spires, and more prominent ribbing.
Description. — Shell slightly smaller than average, with 4l/2
normally coiled whorls. Apex slightly protruding, spire flatly coiled,
body whorl descending rather rapidly, H/D ratio 0.430. Apical whorls
I"*, typical sculpture remaining in sutures. Postnuclear sculpture of
low, rounded, crowded, protractively sinuated radial ribs, whose
interstices are about equal to their width. Body whorl too worn for
accurate rib count. Microsculpture occasionally visible as extremely
fine microreticulation, with a secondary sculpture of spiral cords (?)
that are almost equal to the major radial ribs in size. Sutures deep,
whorls strongly rounded above, flattened laterally down to right-
312
SOLEM: ENDODONTOID LAND SNAILS
2.70
2.56
2.43
2.30
E 2.17
2.04
1.91
1.77
tubuaiana
4.21 4.47 4.73 5.00
Diameter in mm.
FIG. 136. Scatter diagram plotting height and diameter for Australdonta raii-avaeana and A. tubuaiana.
5.26
angled periphery, lower palatal margin flattened, basal and colu-
mellar margins progressively more strongly rounded. Ground color
leached from shell, traces of irregularly spaced, narrow to broad,
reddish flammulations remaining above periphery. Umbilicus broadly
V-shaped, regularly and evenly decoiling, contained 2.97 times in the
diameter. Aperture subovate. flattened laterally above and below
right-angled periphery, inclined about 20° from shell axis. Parietal
wall with 2 barriers, extending posteriorly to line of vision: upper
very high and slender, posterior third markedly elevated, with
gradual anterior descension until just before termination; 2nd a
raised threadlike ridge, slightly more elevated on posterior visible
third, terminating opposite end of upper parietal. Columellar wall
without barrier. Palatal barriers 3, deeply recessed, extending
posteriorly almost one-quarter whorl: lower basal in position, a low
lamellar blade with gradual anterior descension; 2nd more deeply
recessed, slightly reduced in height, a V-shaped lamellar blade with
very gradual anterior descension; 3rd slightly supraperipheral, a
threadlike ridge, deeply recessed. Height of holotype 1.51 mm.,
diameter 3.52 mm.
Holotype. — Austral Islands: Tubuai, Station 703,
200-300 yd. inland, south of Hoopua, at 5 ft. elevation
in sandy soil. Collected by Yoshio Kondo and Donald
Anderson on August 18, 1934. BPBM 147726.
Range. — Tubuai, Austral Islands.
Paratype. - BPBM 147726.
Material. - Tubuai: south of Hoopua (Station
703), 200-300 yd. inland at 5 ft. elevation (2 specimens,
BPBM 147726).
Remarks. — The obviously subadult holotype has
patches of the microsculpture preserved. Whether this
sculpture should be interpreted as an intensification of
the spiral grooving seen in other Australdonta, or
actually is very large spiral cording, is uncertain.
While I have described it as the latter, only better
preserved material will enable deciding this problem.
The specific name pharcata refers to the wrinkled
appearance of the shell sculpture.
Although the palatal barriers resemble those of
other Australdonta in shape, they are much longer
and the normal 2nd palatal is absent. Similarly, the
parietals in A. pharcata seem to occupy the position of
the normal 2nd and 3rd parietals, with the upper and
lower lost, those remaining being greatly elongated.
As in A. ectopia, the ribbing is greatly reduced in
prominence and very crowded. Unfortunately, the
shell surface was too worn for accurate rib counts to
be made. In degree of depression and umbilical width,
A. pharcata is intermediate between A. ectopia and
the more typical Australdonta.
Australdonta ectopia, new species. Figure 137d-f.
Diagnosis. — Shell very large, diameter 4.38-4.77 mm. (mean 4.57
with 5'» tightly coiled whorls. Apex and early spire flat or
__abc
FIG. 137. a-c, Auxtraldonta pharcata. new species. Station 703, Hoopua, Tubuai, Austral Islands. Holotype. BPBM 147726; d-f,
Australdonta ectopia, new species. Station 652. Anatonu Village, Raivavae, Austral Islands. Holotype. BPBM 147389. Scale lines equal 1 mm.
(MM).
313
314
SOLEM: ENDODONTOID LAND SNAILS
barely elevated, lower spire descending slightly, last quarter to third
of body whorl descending moderately, H/D ratio 0.331-0.383 (mean
0.357). Umbilicus broadly open, cup-shaped, regularly decoiling,
contained 2.25-2.27 times (mean 2.26) in the diameter. Postnuclear
sculpture of low, rounded, rather inconspicuous, strongly protractive-
ly sinuated radial ribs, whose interstices are about 2-3 times their
width, probably about 200 on body whorl, but all specimens too
worn to obtain an accurate count. Microsculpture not clearly
discernable because of worn surface, except for slight traces of
secondary spiral grooving on an occasional part of shell surface.
Sutures deep, whorls strongly rounded above, flattened laterally
above and below acutely angled periphery, basal margin evenly
rounded to somewhat shouldered umbilical margin. Subperipheral
sulcus relatively distinct, supraperipheral sulcus very weak or absent.
Aperture subquadrangular, flattened laterally above periphery, with
flatly rounded lower palatal and basal margin, inclined about 30°
from shell axis. Parietal wall with single, supramedial, threadlike
trace, extending posteriorly three-sixteenths of a whorl. Columellar
and palatal walls without barriers.
The very wide umbilicus, extremely depressed
shape, single parietal thread, and acutely angulated
periphery at once separate Australdonta ectopia from
the other species of Australdonta. While A. radiella
has lost its columellar and palatal barriers, that
species has many threadlike traces on the parietal
wall. Extralimital species, such as Nesodiscus fabre-
factus and some of the Hawaiian Cookeconcha agree
in having only a single parietal remaining, but these
species show numerous differences in size, shape and
ribbing.
Description. — Shell very large, with slightly less than 5% tightly
coiled whorls. Apex and early spire very slightly sunken beneath
level of antepenultimate whorl, penultimate whorl descending slowly,
last third of body whorl descending moderately rapidly, H/D
ratio 0.331. Embryonic whorls slightly less than I1 2, sculpture near
terminal part of widely spaced, low, strongly angled radial ribs, apex
worn. Postnuclear whorls worn, with occasional patches of low,
rounded, strongly protractively sinuated radial ribs visible. Probably
about 200 ribs present on body whorl. Microsculpture occasionally
detectable through weak spiral grooves, but no trace of primary
sculpture remaining. Sutures deep, whorls strongly rounded above,
flattened laterally down to acutely angled periphery, basal and lower
palatal margin gently rounded, umbilical margin strongly rounded.
Subperipheral sulcus prominent, weak supraperipheral sulcus visible
on lower spire but disappearing on most of body whorl. All traces of
color leached from shell. Umbilicus widely open, cup shaped,
regularly decoiling, contained 2.27 times in the diameter. Aperture
subquadrangular, flattened laterally above acutely angled periphery,
inclined about 30° from shell axis. Parietal wall worn, a short, deeply
recessed trace of the threadlike parietal visible. Columellar and
palatal walls without barriers. Height of holotype 1.58 mm., diameter
4.77 mm.
Holotype. — Austral Islands: Raivavae Island,
Station 652, hillside one-quarter mile east of Anatonu
village at 50-150 ft. elevation. Collected by Yoshio
Kondo and Donald Anderson on August 11, 1934.
BPBM 147389.
Range. — Raivavae, Austral Islands.
Paratypes. — Same as list of material.
Material. -- Raivavae: one-quarter mile east of
Anatonu village (Station 652) at 50-150 ft. elevation (5
specimens, BPBM 147389).
Remarks. - The holotype is unusual in having
nearly all of the parietal barrier worn away, but it is
clearly visible in the three fragmentary examples and
the other complete adult. Only the larger Nesodiscus
have gone further in reduction of the barriers. The
traces of spiral grooving and the presence of Austral-
donta pharcata, which is intermediate in spire height
and umbilical width, permit this species to be classified
as an Australdonta. Adequate material may show
sufficient differences to warrant placing A. ectopia in a
separate genus. It is the Raivavae equivalent of
Nesodiscus in structure, but obviously derived from
Australdonta because of its sculpture and shape.
A. pharcata is quite similar in shape and size, but
differs by its 2 parietals, 3 palatals, higher spire,
narrower umbilicus, and coarser ribbing.
Associated with A. ectopia were A. raivavaeana
(68 specimens), Minidonta anatonuana (29 specimens),
and four specimens each of M. micraconica, M.
sulcata, and M. planulata, making this the single most
productive station on the island.
Genus Taipidon, new genus
Medium- to large-sized Endodontidae, with typical apical
sculpture. Secondary spiral cording absent only in varidentata,
woapoensis. and octolamellata; weak in anceyana and fragila;
strongly developed in other species. Major radial ribbing closely
spaced in petricola, fragila, and caridentata, widely spaced only in
anceyana. Apex and spire usually slightly to moderately elevated,
depressed in fragila, greatly elevated in semimarsupialis. Body whorl
slightly to moderately descending, evenly rounded or laterally
compressed, only in anceyana with compression above and below
periphery. Whorls generally 5'/8-6, rarely reduced in number (fragila)
or greatly increased (semimarsupialis). Umbilicus moder-
ately open, generally V-shaped and relatively wide (woapoensis,
octolamellata, marquesana, and anceyana) or U-shaped and
somewhat narrower (remaining species), except modified to form a
secondary brood pouch in semimarsupialis. Parietal barriers variable
in number: 4 in petricola; 3 in woapoensis, octolamellata, and
man/uesana; 2 in the remaining species; generally without accessory
traces, such present normally only in centadentata. Columellar
barrier absent or reduced in semimarsupialis, woapoensis, and
marquesana, split into many traces in centadentata. Palatals highly
variable in length, form and position; accessory traces present in
petricola, all palatals split and reduced in length in centadentata.
Penis with a submedian pustulose glandular zone and two pilasters
of varying size and relative prominence, in some species split into
elongated beads. Penial retractor inserting on a fleshy extension of
the penis head in all species examined except for petricola, arising
from diaphragm (centadentata, semimarsupialis) or columellar
retractor (petricola), unknown in other species. Genital and pallial
anatomy otherwise typical of Endodontidae. Jaw of separate,
rectangular plates (i-aridentata, fragila) or more elongated plates
with partial fusion (centadentata, semimarsupialis), unknown in
other species. Radular teeth typical of family, number per row
moderately increased in semimarsupialis. greatly increased in
centadentata.
Type species. — Pithys analogica Pease, 1870.
The generic name Taipidon is derived from Taipi
Valley on Nukuhiva, the setting for Herman Melville's
novel "Typee" (a book that first kindled my interest in
the Pacific), combined with "don" for tooth, referring
to the apertural barriers. Unfortunately, none of the
conchologically more generalized species were available
SYSTEMATIC REVIEW
315
for dissection. The anatomy of the type species, Pithys
analogica Pease, 1870, has not been studied.
Less material was available from the Marquesas
than from any other major island group, including
Hawaii. Five species, including all of the more
generalized, are known only from the collections of
Andrew Garrett prior to the 1880's. All the remaining
material was collected by members of the Bishop
Museum "Pacific Entomological Survey" team, which
was active in the Marquesas between 1929 and 1932
(Adamson, 1936, pp. 3-6). Although the collector of
each specimen is not recorded in the Bishop Museum
catalogue, comparing dates of collection with the field
itinerary established that while Adamson explored
niches suitable for endodontids, the other entomolo-
gists focused on different microhabitats. They collect-
ed essentially no endodontids. Thus the apparent
absence of Taipidon from Uahuku, Fatuuku, Tahuata,
Mohotani, and Fatuhiva probably expresses only the
absence of collecting effort. The species described here
undoubtedly represent only part of the fauna that was
still extant in the early 1930's, since collections were
made by non-malacologists. An estimate by Cooke
(1929) that less than half of the Marquesan shells have
been collected probably is conservative.
The similarities of Taipidon are with Mau-
todontha (Garrettoconcha) primarily, but a few fea-
tures are shared with Anceyodonta, while an anatom-
ical advance is present otherwise only in Plan-
udonta, which is an obvious derivative of Taipidon.
Generic recognition is based upon the consistent
development of a pustulose glandular zone in the
penis, the patterns of alteration in the penial pilasters,
frequent development of a fleshy extension to the
penis head, tendency towards having only 2 parietals,
and different combination of conchological characters
than those found in Mautodontha or Anceyodonta.
The genera are at the same stage of morphological
complexity and share certain trends, but represent
series that are different in average pattern and with
morphologic gaps between them.
The rather narrow, regularly decoiling, either U-
or V-shaped umbilicus of Taipidon with somewhat
corresponding low or moderately elevated spire agrees
with the pattern of Mautodontha (Garrettoconcha)
and Mautodontha, S.N., respectively. Similarly, the 4
parietals of T. petricola, with some size reduction in
the 2nd and 3rd, find their near duplication in M.
consobrina, M. saintjohni, and M. maupiensis. T.
petricola agrees with the tendencies in Anceyodonta in
its possession of accessory apertural traces and the
presence of secondary spiral cording. Mautodontha
tends toward very fine and crowded ribbing with
secondary spiral cording appearing only in the Austral
Island M. ceuthma. Anceyodonta has a very narrow
umbilicus, sometimes rapidly decoiling on the last
whorl, has a strong tendency toward development of
sulci and tends to have a verv elevated shell.
Unfortunately, only fragmentary anatomical material
of Mautodontha was available, so that the extent of
anatomical variation remains unknown. The two
equal-sized, low and rounded penial pilasters, lack of a
pustulose zone in the penis, and absence of a fleshy
extension to the penis head contrast with the
structures in Taipidon, where the pilasters are highly
unequal, there is a distinct pustulose zone in the penis,
and there is a fleshy extension to the penis head in all
but T. petricola.
Except for T. petricola, which is by far the
smallest Taipidon (table XCII), the species show a
strong trend toward the presence of only 2 parietals
and lack accessory traces (except the obvious secon-
dary specialization of T. centadentata). This differs
from both Anceyodonta and Mautodontha, although
the latter shows a strong trend toward loss of the
palatal and parietal barriers (M. consimilis, etc.). At
first, T. petricola would seem more similar to
Mautodontha because of its parietal barriers, accessory
traces, relatively high spire, and lack of a fleshy
extension to the penis head. The strong secondary
spiral cording, pustulose zone within the penis, and
very unequal penial pilasters clearly relate it to the
remaining Taipidon. Its presence on Eiao and Hatutu,
the northwestern outliers of the Marquesas, is of
uncertain importance. Its small size and 4 parietal
barriers would seem generalized, but this is the
smallest species in which the penial retractor origi-
nates from the columellar muscle. Since in both the
relatively large T. centadentata and T. semi-
marsupialifi the penial retractor originates from the
diaphragm, this is particularly unusual. No other
aspect of the anatomy shows size reduction associated
characters, such as were found in Rhysoconcha (pp.
255-256), but more detailed study of T. petricola is
needed.
Patterns of variation in Taipidon are relatively
simple, but of uncertain systematic importance. With
the frustratingly limited material available, it seems
best to retain this as a single genus, but somewhat
more broadly defined than the Rapan genera, for
example. Together with T. petricola, the species
described by Garrett and Pease, T. woapoensis, T.
octolamellata, T. maruuesana, T. anceyana, and T.
analogica, form a reasonably unitary series. They are
geographically separated, with only T. anceyana and
T. octolamellata described from the same island
(Hivaoa). No exact locality is known for T. analogica.
The species show minor variations in a few characters
and differ in their combinations, except for T.
petricola, which is significantly smaller, has 4 parietals
and much more crowded ribbing (probably essentially
a function of smaller size). The other species will have
either 3 (woapoensis, octolamellata, marquesana) or 2
(anceyana, analogica) parietals; a relatively wide and
V-shaped (woapoensis, anceyana, marquesana) or
narrower and U-shaped (octolamellata, analogica)
umbilicus; strong (analogica), weak (octolamellata,
p o E
5 a a
3 ex x
Z U3 UJ
2
<
S
col
CM|
U
c|
Z
<
2
§
1/5
CM|
316
COl
rt
01
I
CM
CO
I
CO
c-
O)
Se-
e-
co'
oT
OO
CM'
10
co
co'
If
10
CM
en-
CO
OO
CM
CO
•2
o
jr
S
CO
00
10
CD
00
CD
00
CO
CO
^
c-
co
IO
00
CO
10
10
3?
CO
to
10
10
•rj 10
rt £2
OS ^
O g,
x S5
en
co
10
CM
•*
IO
CO
IO
a ^
CO
CO
•*'
CO
co'
M1
it
10
co'
CO
CNl'
10
CO*
10
co
CD
co'
CO
co'
CM
CD
00
co'
CM
oT"
CD
en
10
a
a:
0~
00
1
CM
10
0?
C"
10
IO
1
0
CO
t-
en
IO
CO
o
CO
CO
CO
ar
o
co"
CO
o
e-
•<*
SYSTEMATIC REVIEW
317
anceyana), or no (marquesana, woapoensis) secondary
spiral cording; an absent or weak (marquesana,
woapoensis), typical (analogica) or prominent (ance-
yana, octolamellata) columellar lamella; with a
slightly (woapoensis, octolamellata, marquesana),
moderately (anceyana), to strongly (analogica) ele-
vated spire, which also is present in petricola. Very
limited material was seen and, except for T. woap-
oensis, these are lowland species that undoubtedly are
extinct. Despite the differences of T. petricola, this is a
unified series of species (table XCII).
Two pairs of species depart significantly from this
basic pattern in one or more character complexes. On
Hivaoa, T. fragila and T. varidentata have extremely
thin and fragile shells, palatal barriers that are very
short plus variable in number and positon, no spiral
cording in T. varidentata and extremely fine secon-
dary cording in T. fragila, and major radial ribbing
that is much finer, but not more crowded than in the
remaining Taipidon. Only partial soft parts were
available of each species and there are no anatomical
peculiarities confined to this pair.
On Nukuhiva, T. centadentata and T. semi-
marsupialis share an anatomical trend unique in the
Endodontidae, but have differing sets of conchological
specializations. Both species have the number of
radular teeth significantly enlarged (13-15 laterals and
10-13 marginals in semimarsupialis; 22-23 laterals and
16-17 marginals in centadentata) compared with the
normal 8-10 laterals. In T. centadentata the teeth are
proportionately narrower than normal, but not greatly
altered in shape. Whether this accompanies a change
of diet or is caused by some other factor is unknown,
but should be investigated. T. centadentata otherwise
agrees well with the analogica series in shape and
sculpture, differing only in its peculiarly altered
apertural barriers. The major parietal barriers are
greatly elongated and there are fifteen to twenty
accessory traces. The columellar and palatal walls
have many very short threadlike traces mounted on a
raised callus. This is quite different from the patterns
of palatal traces found elsewhere in the Endodontidae
(see pp. 62-63). T. semimarsupialis has developed a
secondary brood pouch by gradual narrowing of the
opening. The high spire and greater whorl count (table
XCII) of semimarsupialis are correlatives of brood
pouch formation. The absence of radial sculpture from
the umbilical walls is not surprising, considering the
apparently abrupt alteration to brood pouch structure.
Without collection of additional material, partic-
ularly from the islands unexplored for endodontids, it
will not be possible to assess the systematic impor-
tance of the variations outlined above. Pending the
availability of further material, I prefer to list them as
species groups within Taipidon.
No trends of variation within the genus are clear,
unless the reduction in number of parietals is more
than just correlated with size increase. There is an
interesting pattern of variation in essentially sympat-
ric species. On Nukuhiva, T. centadentata and T.
semimarsupialis are sympatric, and on Hivaoa, T.
fragila and T. varidentata were collected on the same
ridge within 90 ft. elevation of each other.1 Each of
these pail's has one species with the pilaster pattern as
in the typical Taipidon, the other with the penis
shorter and the major pilaster broken up or partly
modified into elongated globular knobs (figs. 138f, h;
139b, f). Such a pattern of change would act to
reinforce isolation between the species, a necessity
when species are sympatric. The penial differences
between these pairs are much greater than between
allopatric species pairs (see pp. 80-81).
Classification of the Taipidon species is as follows:
Group of Taipidon analogica — shell small to
very large; usually with secondary spiral cording;
umbilicus U- or V-shaped; 2-4 parietals; spire
slightly to moderately elevated —
Taipidon petricola petricola, new species and
subspecies
T. petricola decora, new subspecies
T. octolamellata (Garrett, 1887)
T. woapoensis (Garrett, 1887)
T. marquesana (Garrett, 1887)
T. anceyana (Garrett, 1887)
T. analogica (Pease, 1870)
Group of Taipidon centadentata — shell large;
secondary spiral cording present; umbilicus U-
shaped or modified to form a brood pouch; 2
parietals; spire moderately to strongly elevated;
radular teeth increased in number —
T. semimarsupialis, new species
T. centadentata, new species
Group of Taipidon varidentata — shell small and
very thin; ribbing very fine; umbilicus narrow, U-
shaped; palatals short and clustered on lower
palatal wall; spire depressed to weakly elevated —
T. varidentata, new species
T. fragila, new species
While possibly Planudonta could be considered a
species group of Taipidon, the reasons for generic
recognition are discussed below.
KKY TO THK GKNUS Taipidon
1. Umbilicus not modified to form a brood pouch 2
Umbilicus modified to form a brood pouch.
Taipidon semimarsupialis, new species
'T. fragila was found only above 3,900 ft. elevation; T. varidentata
only below 3,860 ft. elevation. The collections of the two species were
made at different times, usually in different years or at least six
months apart. Whether they are altituclinalty separated or not
remains to be determined. Since only one or two examples were
collected each time, probably by different people, the reality of this
separation requires the Scotch verdict "not proved."
318
SOLEM: ENDODONTOID LAND SNAILS
2. Palatal wall with 3 or 4 typical barriers 5
Palatal wall with many traces or short barriers clustered on
lower palatal wall 3
3. Palatal barriers very short, 1-5 in number, located on lower
palatal wall (figs. 145a, c) 4
Palatal barriers numerous short traces on a raised callus (fig.
144a, b) Taipidon centadentata, new species
4. Spire flat or depressed; umbilicus contained about 5.00 times in
diameter; barriers reduced in size.
Taipidon fragila, new species
Spire slightly and evenly elevated; umbilicus contained about
3.25 times in the diameter; barriers larger.
Taipidon varidentata, new species
5. Parietal barriers normally 4; mean diameter less than 3.5 mm.;
accessory palatal traces present 6
Parietal barriers 2 or 3; mean diameter over 3.9 mm.; no
accessory palatal traces 7
6. First palatal trace small; Hatutu Island.
Taipidon petricola petricola, new species and subspecies
First palatal trace large; Eiao Island.
Taipidon petricola decora, new subspecies
7. Columellar barrier very weak or absent 8
Columellar barrier typical to large in size 9
8. Shell larger, ribs more numerous; Uapou Island.
Taipidon woapoensis (Garrett, 1887)
Shell smaller, ribs fewer in number; Nukuhiva Island.
Taipidon marquesana (Garrett, 1887)
9. Spire low, mean H/D ratio less than 0.550 10
Spire elevated, mean H/D ratio about 0.600.
Taipidon analogica (Pease, 1870)
10. Parietal barriers 3; umbilicus U-shaped.
Taipidon octolamellata (Garrett, 1887)
Parietal barriers 2; umbilicus V-shaped.
Taipidon anceyana (Garrett, 1887)
GROUP OF Taipidon analogica (Pease, 1870)
Taipidon petricola petricola, new species and sub-
species. Figures 138a-b; 140a-b.
Diagnosis. — Shell very small, diameter 2.65-3.15 mm. (mean
2.88 mm.), with 5-5% tightly coiled whorls. Apex and spire
moderately elevated, rounded above, last whorl descending a little
more rapidly, H/D ratio 0.512-0.614 (mean 0.575). Umbilicus narrow,
U-shaped, slightly and regularly decoiling, contained 4.40-5.31 times
(mean 4.79) in the diameter. Postnuclear sculpture of narrow,
crowded, lamellate, protractively sinuated radial ribs, 108-124 (mean
117.3) on the body whorl, whose interstices are l'/2-2 times their
width. Microsculpture of very fine radial riblets, three to six between
each pair of major ribs, crossed by barely visible, extremely crowded
spiral riblets, with a secondary microsculpture of prominent spiral
cording over entire shell surface. Sutures deep, whorls strongly
rounded above and on basal margin, with evenly rounded outer
margin. Aperture ovate, with evenly rounded outer margin, inclined
about 10° from shell axis. Parietal barriers 4, extending posteriorly
almost one-quarter whorl, with one threadlike accessory trace; 1st
parietal high and bladelike, expanded and serrated above on
posterior half, with gradual anterior descension; 2nd parietal with
posterior slightly reduced in height, sharply descending to threadlike
anterior two-thirds that terminates slightly in front of upper
parietal; 3rd parietal equal or slightly higher than 1st on expanded
posterior third, with rather gradual anterior descension to threadlike
anterior half; 4th parietal slightly reduced in height from 3rd,
slightly shorter posteriorly, with longer anterior threadlike portion.
Parietal trace inconspicuous, rather short, deeply recessed within
aperture. Columellar barrier a moderately prominent ridge, twisting
slightly downwards from plane of coiling, reaching across top of
Columellar callus. Palatal barriers 4, extending posteriorly almost
three-sixteenths of a whorl, generally with six or seven accessory
traces: lower on basal margin, a high thin lamella, expanded and
serrated above on posterior half, somewhat sinuately twisted
anteriorly, with rather sharp anterior descension, only slightly
recessed within aperture; 2nd and 3rd distinctly higher and longer
than 1st, progressively more deeply recessed and with more gradual
anterior descension, superior expansion and serration more obvious;
4th supraperipheral, greatly reduced in height, scarcely more
prominent than second and third accessory traces. Accessory traces
located between columellar and 1st palatal; 1st and 2nd palatal; 2nd
and 3rd palatals; 3rd and 4th palatals; with two or three above 4th
palatal. Second and third palatal traces much larger than upper or
lower traces.
The presence of 4 major parietals and six or seven
accessory palatal traces combine to separate Taipidon
petricola petricola from the other Marquesan taxa. A
subspecies from nearby Eiao Island, T. petricola
decora, differs in its reduced 2nd parietal, enlarged
first palatal trace and weaker secondary spiral cording.
Description. — Shell of average size, with 55/s relatively loosely
coiled whorls. Apex and spire moderately elevated, rounded above,
last whorl descending more rapidly, H/D ratio 0.579. Embryonic
whorls 1%, sculpture eroded above, visible in umbilicus as relatively
widely spaced radial riblets, crossed by very fine and widely spaced
spiral ribs. Remaining whorls with quite closely set, lamellate,
protractively sinuated radial ribs, 124 on the body whorl, whose
interstices are about twice their width. Microsculpture consisting of
very fine radial riblets, extremely fine spiral riblets, and quite
prominent, rather widely spaced spiral cords. Microsculpture some-
what reduced on upper shell surface. Sutures relatively deep, whorls
rounded above, slightly flattened below periphery. Umbilicus
narrowly U-shaped, regularly decoiling, contained 4.52 times in the
diameter. Color very light yellow-brown with narrow, irregular,
reddish flammulations. Aperture ovate, laterally compressed, inclined
about 15° from shell axis. Parietal barriers 4, extending less than
one-quarter whorl: numbers 1, 3, and 4 high lamellate blades that
are rounded above with minute serrations; 2nd reduced in size to a
lamellate ridge. Columellar barrier a short broad ridge, nearly
reaching apertural margin. Major palatal barriers 4, slightly more
than one-eighth whorl in length: lower 3 moderately high, with
rounded and serrated tops; upper palatal a narrow, V-shaped ridge,
not recessed within aperture. Palatal traces located between
columellar and 1st palatal; 1st and 2nd palatals; 2nd and 3rd
palatals; 3rd and 4th palatals and with three above the upper palatal
barrier. All palatal traces low, short threadlike structures. Height of
holotype 1.81 mm., diameter 3.13 mm.
Holotype. — Marquesas Islands: Hatutu Island,
uplands near the middle of island on east side at 1,080
ft. elevation. Collected from a very dry hillside under
dead wood on September 29, 1929 by members of the
Pacific Entomological Survey. BPBM 95576.
Range. — Hatutu Island, Marquesas.
Paratypes. — Same as list of material.
Material. — Marquesas Islands: Hatutu Island,
uplands near the middle of island on east side at 1,080
ft. elevation (19 specimens, BPBM 95574-6).
Remarks. - The name petricola was chosen to
characterize the small size of the island from which
this form is known. Hatutu is in the northeastern
outliers of the Marquesas and only a few miles from
Eiao on which a very closely related subspecies,
Taipidon petricola decora, is found. This species shows
the most similarities to Anceyodonta and Mau-
todontha of any Marquesan endodontid, but the
genital anatomy clearly relates it to the other
SYSTEMATIC REVIEW
TABLE XCIII. - LOCAL VARIATION IN TAIPIDON
319
Name
eiricola petricola
BPBM 95574-6
peaicola decora
BPBM 95542-3.
BPBM 95524,
BPBM 95526.
BPBM 95553-4
woapoensls
BPBM 3464,
BPBM 8693
marquesana
BPBM 3437
Zurich
anceyana
BPBM 3118
analogica
BPBM 115307
BPBM 115291
semimarsupialis
BPBM 96051-2
centadentata
BPBM 96053,
BPBM 96096,
BPBM 96100-1
varidentata
Number of
Specimens
14
25
BPBM 104635,
BPBM 98793, -63,
BPBM 94799
Ribs Height
1.67*0.068
(1.42-1.82)
1.76*0.040
(1.52-2.05)
1.95i0.038
(1.79-2.09)
56.5±4.50 1.81*0.127
(52.0-61.0) (1.62-2.05)
67.8±2.64 1.81i0.023
(56.0-80.0) (1.72-1.92)
64.7±6.44 2.24*0.077
(52.0-73.0) (2.09-2.32)
2.62*0.285
(2.28-3.48)
3.12*0.184
(2.78-3.41)
2.73±0.044
(2.45-3.11)
1.82*0.116
(1.59-2.05)
Taipidon. According to Adamson (1935, p. 32) it was
collected "under bark," although the data in the
catalogue at the Bishop Museum only mention that
BPBM 95574 (two juveniles) were collected "on
ground" and the "others under dead wood on ground."
Possibly T. petricola lives under loose bark on gently
slanting stilt roots as do some of the Samoan
Charopidae (Solem, unpublished}. If so, this would be
a major change from the ground restricted habitat
shown by most Endodontidae.
Differences from T. petricola decora are covered
in the diagnosis above. The size difference (table
XCIII) may be an artifact of sampling, since the
measured material of T. p. decora contained many
more gerontic individuals than the measured material
of petricola. The barrier differences appear constant
and were used to differentiate the subspecies.
Description of soft parts. — Foot partly retracted in all
specimens; tail rounded behind, not tapering. Sole undivided. Pedal
grooves typical, no caudal horn or middorsal groove. Head retracted
completely.
Body color light yellow-white, no darker markings.
Mantle collar with thickened edges, no glandular extension onto
lung roof. Pneumostome and anus typical.
Pallial region extending five-eighths whorl apically. Lung roof
with fine white granulations edging principal pulmonary vein and
Diameter
H/D Ratio
Whorls
D/U Ratio
2.88*0.069 0.575t0.0147 53/8 4.79*0.131
(2.65-3.15) (0.512-0.614) (5-55/8) (4.40-5.31)
2.96*0.038 0.594.0.0083 51/4 5.18*0.123
(2.75-3.15) (0.542-0.629) (43/4-53/4) (4.21-6.00)
4.27*0.062 0.450*0.0057 53/4 2.96*0.061
(4.01-4.44) (0.435-0.476) (55/8-6) (2.76-3.20)
3.87*0.099 0.466±0.0214 55/8 3.01*0.117
(3.77-4.07) (0.430-0.504) (51/2-53/4) (2.78-3.17)
3.92*0.071
0.462^0.0100
(3.64-4.34)
(0.420-0.527)
5 1/2*
(5 1/8-6)
3.00*0.053
(2.67-3.22)
4.96±0.242 0.453*0.0087
(4.50-5.33) (0.435-0.463)
53/4 2.89*0.055
(5 3/8-6) (2.78-2.96)
4.36*0.302
0.597*0.0230
6 3/8-
(3.97-5.26)
(0.556-0.660) (6-7 1/4)
3.94*0.105
(3.65-4.14)
4.23*0.080
0.738 0.0300
7 1/4*
5.25*0.167
(4.08-4.34)
(0.683-0.787) (67/8-71/2)
(4.92-5.46)
4.72*0.062 0.577*0.0050 6* 4.24*0.050
(4.30-5.56) (0.539-0.633) (51/2-63/8) (3.82-4.77)
3.68*0.118
(3.48-4.01)
0.495±0.019
(0.457-0.540)
5 1/8
(4 7/8-5 1/2)
3.21*0.095
(2.98-3.43)
kidney. Kidney about 1.15 mm. long, rectal arm 0.45 mm. long.
Ureter typical, reflexing and opening next to hindgut, opposite end of
kidney rectal arm. Heart 0.5 mm. long, not parallel to hindgut.
Principal pulmonary vein relatively broad, prominent almost to
mantle collar, unbranched. Hindgut typical.
Ovotestis (fig. 138a, G) typical in structure and clump
orientation, extending about one-half whorl above stomach apex.
Hermaphroditic duct (GD) greatly swollen medially, of normal
length, narrowing and reflexing abruptly before entering carrefour.
Albumen gland (GG) larger than shown in drawing, surface rather
finely textured. Talon (fig. 138b, GT) very long and slender with
small, expanded head. Carrefour (X) elongated and expanded,
receiving hermaphroditic duct laterally (fig. 138b). Prostate (DG)
short, two rows of large, bulbous acini opening into a narrow tube
that becomes vas deferens. Uterus (UT) typically bipartite, expanded
lower chamber extending well below end of prostate, tapering to free
oviduct.
Vas deferens (VD) typical, entering penis 0.6 mm. below head
and to side of main pilaster. Penial retractor (PR) arising from
columellar retractor, inserting directly on head of penis. Penis (P)
about 1.51 mm. long, internally with one very high, thin pilaster with
a second much lower, fading out in central region to a pustulose
area, reappearing basally. Atrium (Y) short, wide.
Free oviduct (UV) about equal in length to prostate, only
tapering slightly. Spermatheca (S) with expanded head next to
albumen gland, shaft inserting on penioviducal angle.
Free muscle and digestive systems typical.
Jaw not successfully mounted.
Radula with centrals about 7-8/x wide and 8m long, tricuspid
mesocone equal in length to basal plate, ectocones very small.
FIG. 138. Anatomy of Taipidon: a-b, T. petricola petricola. East side of Hatutu Id., Marquesas. BPBM 95575. a, genital system, 6,
details of carrefour region; c-d, T. petricola decora. Eiao Id., Marquesas. BPBM 95525, BPBM 95542. c, penis, d, interior of penis; e-f, T.
fragila. Mt. Temetiu, Hivaoa, Marquesas. BPBM 115704. e, genitalia, f, interior of penis; g-h, T. varidentata. Mt. Temetiu, Hivaoa,
Marquesas. BPBM 94799. g, genitalia. h, interior of penis. (See Appendix for explanation of abbreviations.)
320
1mm,
FIG. 139. Anatomy of Taipidon: a-c, T. semimarsupialis, Mt. Ooumu, Nukuhiva, Marquesas. BPBM 96051-2. a, genitalia, b, interior of
penis, c, apical portion of pallial cavity; d-f, T. centadentata. Mt. Ooumu, Nukuhiva, Marquesas. BPBM 96053. BPBM 96096. d, pallial
complex, e, genitalia, f, interior of penis. (See Appendix for explanation of abbreviations.)
321
322
SOLEM: ENDODONTOID LAND SNAILS
ab
h
cd
FIG. 140. a-b, Taipidon petricola petricola, new species and subspecies. Uplands of Hatutu Island, Marquesas. Holotype. BPBM 95576; c-d,
Taipidon petricola decora, new subspecies. Eiao Island at 1,850 ft., Marquesas. Holotype. BPBM 95543. Scale line equals 1 mm. Drawings by
YK reproduced through the courtesy of Bernice P. Bishop Museum.
Laterals about 6, ectocone progressively larger, entocone appearing
on 6th tooth. Transition to marginals between 6th and 9th tooth.
Outer marginals missing in all mounts, those present with square
plates, becoming elongately rectangular, very short cusps with split
endocone much longer than mesocone or ectocone.
(Based on BPBM 95575, several whole and partly extracted
examples.)
Taipidon petricola decora, new subspecies. Fig-
ures 49a-c; 138c-d; 140c-d.
Diagnosis. — Shell much smaller than average, diameter 2.75-
3.51 mm. (mean 3.02 mm.), with 5'/4-57/s normally coiled whorls.
Apex and spire moderately and evenly elevated, sometimes rounded
above, last whorl descending distinctly more rapidly, H/D ratio
0.542-0.629 (mean 0.591). Umbilicus narrowly open, U-shaped,
regularly decoiling, contained 4.65-6.00 times (mean 5.12) in the
diameter. Postnuclear whorls with narrow, prominent, crowded,
protractively sinuated radial ribs, 95-107 (mean 102.2) on the body
whorl, whose interstices are l'/2-2 times their width. Microsculpture
of fine radial riblets, three to six between each pair of major ribs,
crossed by extremely fine and crowded spiral riblets, with weak
secondary spiral cording usually visible on shell base. Sutures
prominent, whorls strongly rounded above and on basal margin, with
evenly rounded outer margin. Aperture ovate, with evenly rounded
outer margin, inclined about 15° from shell axis. Parietal barriers 3
(15 per cent) or 4 (85 per cent), extending posteriorly three-sixteenths
of a whorl, with one (85 per cent) or two (15 per cent) accessory
traces: upper parietal high and slender, weakly expanded and
serrated above on posterior five-eighths, with rather gradual anterior
descension until just before termination; 2nd parietal, when not
reduced to a deeply recessed threadlike trace, a very low bladelike
lamella, weakly elevated and expanded on posterior third, with
anterior threadlike portion that terminates opposite end of upper
parietal; 3rd parietal distinctly higher than 1st, expanded and
serrated above on elevated posterior third, with rather gradual
descension to anterior third that is an elevated threadlike ridge; 4th
parietal intermediate in height between 2nd and 1st, moderately
expanded above on posterior half, with gradual anterior descension.
SYSTEMATIC REVIEW
323
Accessory trace located below 4th parietal, short and very deeply
recessed; often 2nd parietal reduced to a deeply recessed barely
visible threadlike trace. Columellar wall with high, prominent,
bladelike barrier, with relatively sharp anterior descension, twisted
slightly downward midway across columellar callus. Occasionally a
barely visible to weak threadlike trace lies above columellar. Major
palatal barriers 4, extending posteriorly more than one-eighth whorl,
with five to seven accessory traces, the lower almost equal in height
to upper palatal: lower three palatals high and bladelike, flattened
and expanded above posteriorly, with progressively more gradual
anterior descension; 4th palatal supraperipheral, greatly reduced in
height, a moderately recessed, V-shaped ridge. Accessory traces
located between columellar and 1st palatal; 1st and 2nd palatals;
2nd and 3rd palatals; 3rd and 4th palatals, occasionally absent; and
two or three above 4th palatal.
The great reduction of the 2nd parietal and much
larger size of the lower palatal trace are the
systematically important characters separating Taipi-
don petricola decora from the nominate subspecies.
The great development of accessory traces at once
serves to separate both races of T. petricola from other
Marquesan species.
Description. — Shell small, with 5'j normally coiled whorls.
Apex and spire moderately and evenly elevated, last whorl
descending more rapidly. H/D ratio 0.578. Apical whorls 1 ;I/B,
sculpture of fine radial riblets with faint traces of micro-radial
ribbing and distinctly finer and more crowded spiral riblets.
Postnuclear whorls with high, prominent, lamellar, crowded, protrac-
tively sinuated radial ribs, 107 on the body whorl, whose interstices
are about twice their width. Microsculpture of fine radial riblets,
three to five between each pair of major ribs, crossed by barely
visible spiral riblets, with a secondary microsculpture of irregularly
spaced spiral cording on shell base. Sutures impressed, whorls
strongly rounded above and on basal margin, slightly compressed
laterally below periphery. Color light yellow-brown, with prominent,
zigzagged, reddish flammulations that narrow on shell base. Umbil-
icus rather narrow, U-shaped, regularly decoiling, contained 5.29
times in the diameter. Aperture elongately-ovate, slightly compressed
laterally, with evenly rounded outer margin, inclined about 15° from
shell axis. Parietal barriers 4, extending posteriorly about three-
sixteenths of a whorl, with one very faint, deeply recessed threadlike
trace below 4th parietal: form of parietals as in "Diagnosis."
Columellar barrier prominent and bladelike, slightly twisted
downward from plane of coiling, with rather sharp descension
midway across columellar lip. Palatal barriers 4, extending
posteriorly more than one-eighth whorl, with six accessory traces:
lower 3 high and bladelike, moderately expanded and serrated above
posteriorly, with progressively more gradual anterior descension; 4th
slightly supraperipheral, a more deeply recessed, prominent V-shaped
ridge. Lower palatal trace, lying between columellar and 1st palatal,
almost as large as 4th palatal; threadlike traces between 1st and 2nd,
2nd and 3rd, with three above 4th palatal. Height of holotype 1.71
mm., diameter 2.96 mm.
Holotype. — Marquesas: Eiao Island, uplands
toward north end on east side of island at 1,850 ft.
elevation. Collected on September 29, 1929, by mem-
bers of the Pacific Entomological Survey. BPBM
95543.
Range. — Eiao Island, Marquesas Islands.
Paratypes. — Same as list of material.
Material. — Eiao: uplands toward north end, east
side of island at 1,850 ft. elevation (25 specimens,
BPBM 95542-3); same area at 1,650 ft. elevation (9
specimens, BPBM 95524-7) in coconut plantation near
center of island at 1,450 ft. elevation under rotting
stem of miro palm (3 specimens, BPBM 95553-4);
Vaitahu Valley at 600 ft. elevation, under decaying
logs (24 specimens, BMNH 1970. 98, collected May 3,
1970 by John Peake).
Remarks. — The presence of the enlarged palatal
trace is constant in all individuals of Taipidon
petricola decora and immediately separates them from
specimens of the nominate form in which this barrier
is a threadlike trace. The difference in size of the 3rd
parietal is generally equally obvious.
Specimens from the upland areas are noticeably
smaller than those from the coconut plantation (table
XCIII). The former are essentially the same size as
those from Hatutu, but the latter are significantly
larger in respect to diameter (with 15 df, "t" = 4.1553),
but not significantly different in H/D or D/U ratios
('7" = 0.9207 and 1.2471, respectively). The large size
of the coconut plantation shells may reflect an
accident of timing. Adamson (1936, p. 68) recorded
that "... in 1927-1929 a party of Tahitians was
employed to plant coconuts near the middle of the
island ...." The coconut plantation specimens of
Taipidon petricola decora were collected October 1,
1929 under a rotting miro palm stem. Probably they
represented the gerontic remnant of the population in
this very recently disturbed area. This collection does
not necessarily indicate the persistance of the popu-
lation under conditions of cultivation. Exactly when
the plantation was planted and how much was cleared
is not known to me.
Additional specimens were obtained in 1970 by
John Peake during a British Museum (Natural
History )-Bishop Museum expedition to the Marquesas.
These specimens from Vaituhu Valley were studied in
1972 and used to prepare Figure 49 of the anatomy.
The shells themselves were typical Taipidon petricola
decora in barrier structure, and consisted of 23
juveniles and 11 adults. Size variation in adults also
agreed with the variation seen in other sets. Only
means and S.E.M.'s are given with shell height
1.69 ±0.05, diameter 3. 03 ±0.06, H/D ratio
0.560 ±0.010, D/U ratio 4.51 ±0.09, and whorl count
5. 18 ±0.09. Because the specimens were preserved in
expanded condition, rib counts were not attempted,
nor could barrier variation be studied.
Dissection of the more complete Vaituhu speci-
mens revealed (fig. 49a) typical Taipidon anatomy,
and showed one possibly significant difference from
the fragmentary material (BPBM 95525, BPBM
95542) dissected earlier (fig. 138c, d). The vas deferens
(VD) inserts far lower on the penis in the Vaituhu
specimen, but pilaster patterns and location of the
pustulose zone are identical. The penis in the Vaituhu
specimen was about 1.8 mm. long, and those studied
earlier about 1.65 mm. long. In all of the specimens,
the penial retractor inserted directly on the penis
head, and the Vaituhu example showed that it
originated from the columellar muscle, as in T. p.
324
SOLEM: ENDODONTOID LAND SNAILS
petricola. Since the anatomy of the Vaituhu specimen
showed no differences of a significant nature from
other Taipidon, I did not prepare a formal description.
The radular teeth (fig. 52) have been discussed
previously.
Taipidon octolamellata (Garrett, 1887). Figure
141e-f.
Pitys octolamellata Garrett, 1887, Bull. Soc. Malacol. France, 4, p.
18 — Dominique (= Hiva Oa), Marquesas; Pilsbry, 1892, Man.
Conchol., (2), 8, p. 95.
Endodonta (Thaumatodon) octolamellata (Garrett), Pilsbry, 1893,
op. cit., (2), 9, p. 26.
Description. — Shell larger than average, with 5l/4 normally
coiled whorls. Apex and spire slightly and evenly elevated, last whorl
descending a little more rapidly, H/D ratio 0.486. Embryonic whorls
1%, sculpture of very fine and crowded radial ribbing, with indication
of microradials near the end of embryonic growth, crossed by slightly
finer and distinctly more crowded spiral riblets. Postnuclear whorls
with high, prominent, protractively sinuated radial ribs, 70 on the
body whorl, whose interstices are 2-4 times their width. Micro-
sculpture of fine radial riblets, eight to twelve between each pair of
major ribs, crossed by exceedingly fine and crowded spiral riblets
that are barely visible under 96 x magnification. A weak secondary
spiral cording is barely visible on shell base near umbilical margin.
Sutures deep, whorls strongly rounded above and on umbilical
margin, slightly compressed laterally above and below evenly
rounded outer margin. Color light yellow horn, with prominent,
rather widely spaced, reddish flammulations above periphery, that
become narrowed, less distinct, and strongly zigzagged below
periphery to umbilical margin. Umbilicus U-shaped, regularly
decoiling to last whorl, which decoils somewhat more rapidly,
contained 3.58 times in the diameter. Aperture ovate, slightly
flattened laterally above and below rounded periphery, inclined
about 10° from shell axis. Parietal barriers 3, extending posteriorly
about three-sixteenths of a whorl: upper a high bladelike lamella,
weakly expanded and serrated above on posterior five-eighths, with
rather sharp and regular anterior descension; 2nd parietal slightly
reduced in height, equally expanded above on posterior half, with
gradual anterior descension until just before end, which extends
moderately in front of upper parietal termination; 3rd parietal an
elevated threadlike ridge, equal in length to 2nd parietal, with
posterior half slightly more elevated than anterior portion. Colu-
mellar barrier a high bladelike ridge, moderately expanded above,
slightly twisted downward from plane of coiling, with sharp anterior
descension midway across lip edge. Palatal barriers 4, extending
posteriorly about one-eighth whorl: lower high and crescentic,
moderately expanded above, with abrupt anterior descension almost
to lip edge; 2nd and 3rd slightly reduced in height, somewhat
flattened above posteriorly, with more gradual anterior descension;
4th supraperipheral, greatly reduced in height and length, moder-
ately recessed within aperture, with gradual anterior descension.
Height of lectotype 2.17 mm., diameter 4.47 mm.
Lectotype. -- Marquesas Islands. Collected by
Andrew Garrett. BPBM 4362.
Range. — Known only from the original collection
on Hivaoa Island, Marquesas Islands.
Materials. -• Marquesas (1 specimen, BPBM
4362).
Remarks. -- Although Garrett (1887c, p. 18)
reported that "Quelques individus ont ete trouves a
ile Dominique, sous du bois pourri," only the single
specimen was located. No material was found by the
Pacific Entomological Survey team, and T. octolamell-
ata may be an extinct lowland species. Its smaller
umbilicus, trace of spiral cording, and large columellar
barrier suggest relationship to T. analogica and T.
petricola, while its low spire and 3 parietals suggest
affinities with T. woapoensis and T. marquesana.
Taipidon woapoensis (Garrett, 1887). Figure
141a-d.
Pitys woapoensis Garrett, 1887, Bull. Malacol. Soc. France, 4, p.
17 — Woapo ( = Uapou) Island, Marquesas, under decaying
vegetation at 2,000 ft. elevation; Pilsbry, 1892, Man. Conchol.,
(2), 8, p. 95 (name only).
Endodonta (Thaumatodon) woapoensis (Garrett), Pilsbry, 1893,
op. cit., (2), 9, p. 27 (name only).
Diagnosis. — Shell somewhat larger than average, diameter 4.01-
4.77 mm. (mean 4.33 mm.), with 5% - 6'/s rather tightly coiled whorls.
Apex and spire very slightly and evenly elevated, not rounded above,
last whorl descending distinctly more rapidly, H/D ratio 0.435-0.476
(mean 0.451). Umbilicus broadly open, V-shaped, regularly decoiling,
last whorl not decoiling more rapidly, contained 2.76-3.20 times
(mean 2.98) in the diameter. Postnuclear sculpture of low,
prominent, rounded, protractively sinuated radial ribs, 69-92 (mean
85.0) on the body whorl, whose interstices are 3-5 times their width.
Microsculpture of fine, radial riblets, eight to twelve between each
pair of major ribs, crossed by extremely fine and crowded spiral
riblets. No secondary spiral sculpture on shell. Sutures impressed,
whorls strongly rounded above and on basal margin, somewhat
compressed laterally. Aperture ovate, somewhat compressed later-
ally, inclined about 20° from shell axis. Parietal barriers 2 (25 per
cent) or 3 (75 per cent), extending posteriorly about three-sixteenths
of a whorl: upper high and bladelike, weakly expanded above on
posterior half, with very gradual descension over anterior half until
just before termination; 2nd with posterior third slightly higher and
more broadly expanded than upper, descending rather abruptly to
threadlike anterior half that extends slightly beyond edge of upper
parietal; 3rd, when present, equal in height to upper posteriorly or
greatly reduced in height, with anterior threadlike portion weaker
than in 2nd parietal. Columellar barrier absent (38 per cent) or a
very deeply recessed, low, and threadlike trace lying parallel to plane
of coiling (62 per cent). Palatal barriers 3 (12 per cent) or 4 (88 per
cent), moderately high and lamellate, extending posteriorly more
than one-eighth whorl: lower basal in position, moderately elevated,
with gradual anterior descension, slightly recessed within aperture;
2nd slightly higher than 1st or equal in height, a little more deeply
recessed, with more gradual anterior descension; 3rd distinctly more
elongated, slightly lower, with very gradual anterior descension, more
deeply recessed; 4th, when present, supraperipheral, a vague,
threadlike trace that is deeply recessed and usually partly
surrounded bv a thickened callus.
Taipidon woapoensis is most closely related to the
Nukuhiva species T. marquesana. They both agree in
the extreme reduction or loss of the columellar barrier,
by reduction of the upper palatal, and their almost
identical shape and umbilical structure. T. marques-
ana is, on the average, much smaller (mean diameter
3.91), and has fewer (mean 65.0 ribs) and more widely
spaced radial ribs on the body whorl. Other species of
Taipidon are distinguished by their larger columellar
barrier, or presence of marked secondary spiral cording
and possession of a narrower umbilicus.
Description. — Shell relatively large, with 55/8 planulate whorls.
Apex flat, spire weakly elevated, body whorl descending more
rapidly, H/D ratio 0.462. Embryonic whorls 1V8, with very fine radial
riblets crossing lower, quite widely spaced, narrow spiral ribs.
Postnuclear sculpture of relatively closely spaced, narrow, quite
protractively sinuated radial ribs, 91 on the body whorl, whose
c-
FIG. 141. a-d, Taipidon woapoensis (Garrett, 1887). a-b, Woapo ( = Uapou) Island, Marquesas. Lectotype. BPBM 3464; c-d, Uapou,
Marquesas. Possible paratype. BPBM 8693; c-f. Taipidon octolamellata (Garrett, 1887). Dominique ( = Hivaoa) Island, Marquesas. Lectotype.
BPBM 4362. Scale lines equal 1 mm. Drawings by YK reproduced through the courtesy of Bernice P. Bishop Museum.
325
326
SOLEM: ENDODONTOID LAND SNAILS
interstices are 3-5 times their width. Microsculpture of fine radial
riblets, eight to twelve between each pair of major ribs, crossed by
extremely fine and crowded spiral riblets. Sutures relatively deep,
whorls strongly rounded above suture, slightly flattened laterally
with gradually rounded lower margin leading to umbilical shoulder.
Umbilicus broadly V-shaped, regularly decoiling, contained 3.10
times in the diameter, with obtusely shouldered margins. Color very
light yellow-brown, with numerous scattered reddish flammulations
present. Aperture ovate, somewhat flattened laterally, inclined more
than 15° from shell axis. Parietal barriers 3, extending posteriorly
three-sixteenths of a whorl: upper 2 equally high and lamellate
posteriorly, 2nd with anterior half threadlike and extending beyond
end of upper; lower much lower and shorter posteriorly, with long
anterior threadlike portion. Columellar barrier a deeply recessed,
very low, threadlike trace, lying parallel to plane of coiling. Palatal
barriers 4, extending slightly more than one-eighth whorl: lower 3
bladelike, gradually descending anteriorly across the low, thin
apertural callus, moderately recessed; upper a more deeply recessed
threadlike trace. Height of lectotype 1.84 mm., diameter 3.98 mm.
Lectotype. — Marquesas Islands: Uapou ( =
Woapo Island). Collected by Andrew Garrett. BPBM
3464.
Range. — Uapou Island, Marquesas Islands.
Paratype. - BPBM 3464, BPBM 8693.
Material. — Marquesas (3 specimens, BPBM 8693,
FMNH 155824, Uapou (5 specimens, BPBM 3464).
Remarks. — In one of the five syntypes from
Uapou Island (BPBM 3464) both the lower parietal
barrier and the upper palatal trace are missing. Two
other examples have the columellar barrier absent.
Otherwise, the specimens agree completely in barrier
size. While the average differences from Taipidon
marquesana are large, overlap does exist and consid-
erable confusion can result if simple measurements are
used. The ribs in T. marquesana are slightly higher
and more sharply outlined than in T. woapoensis.
Possibly, only subspecific differences are involved, but
until new material is available, I follow Garrett in
considering them to be distinct species.
Taipidon marquesana (Garrett, 1887). Figure
142c-d.
Pitys marquesana Garrett, 1887, Bull. Soc. Malacol. France, 4, pp.
18-19 - Nukuhiva, Marquesas; Pilsbry, 1892. Man. Conchol.. (2),
8, p. 96.
Endodonta (Thaumatodon) marquesana (Garrett), Pilsbry, 1893,
op. cit., (2), 9, p. 26.
Diagnosis. — Shell slightly larger than average, diameter 3.64-
4.34 (mean 3.91 mm.), with 5!£-6 rather tightly coiled whorls.
Apex and spire flat to slightly and evenly elevated, last whorl
descending distinctly more rapidly, H/D ratio 0.420-0.527 (mean
0.463). Umbilicus broadly open, V-shaped, regularly decoiling,
contained 2.67-3.22 times (mean 3.00) in the diameter. Postnuclear
sculpture of narrow, prominent, strongly protractively sinuated
radial ribs, 52-80 (mean 65.0) on the body whorl, whose interstices
are 3-5 times their width. Microsculpture of fine radial riblets, six to
ten between each pair of major ribs, crossed by fine and exceedingly
crowded spiral riblets that are visible only under 96 x magnification.
Sutures impressed, whorls strongly rounded above and on basal
margin, slightly compressed laterally. Aperture ovate, slightly
compressed laterally, inclined about 20° from shell axis. Parietal
barriers 2 (25 per cent) or 3 (75 per cent), extending posteriorly about
three-sixteenths of a whorl: upper parietal high and bladelike,
weakly expanded above on posterior third, with gradual anterior
descension until just before end; 2nd parietal distinctly higher and
more strongly expanded above posteriorly, with rather sharp anterior
descension to anterior threadlike half which extends slightly in front
of upper parietal termination; 3rd parietal, when present, a
threadlike ridge that is slightly higher and expanded on posterior
half. Columellar barrier absent (50 per cent) or a weak, deeply
recessed threadlike trace (50 per cent). Palatal barriers 4, extending
posteriorly one-eighth whorl: lower basal in position, a high lamellar
ridge, slightly recessed within aperture, with rather sharp anterior
descension; 2nd and 3rd distinctly higher, longer, with more gradual
anterior descension; 4th supraperipheral, a low threadlike ridge that
is more deeply recessed and shorter than 3rd parietal.
The smaller size and generally fewer and more
widely spaced major radial ribs are the primary
characters separating Taipidon marquesana, found on
Nukuhiva, from the very similar T. woapoensis, found
on Uapou Island. The absence of secondary spiral
cording and the greatly reduced size of the columellar
barrier in T. marquesana separate it from the other
Marquesan species.
Description. — Shell a little larger than average, with 5% rather
tightly coiled whorls. Embryonic whorls slightly elevated, remaining
whorls of spire planulately coiled, last whorl descending distinctly
more rapidly, H/D ratio 0.465. Embryonic whorls 1''2, badly worn,
with only traces of microradial ribbing remaining. Postnuclear
whorls with widely spaced, protractively sinuated, narrow, lamellate
radial ribs, 52 on the body whorl, whose interstices are 3-4 times their
width. Sutures deep, whorls strongly rounded above, compressed
laterally down to obtusely margined umbilicus. Umbilicus broadly V-
shaped, regularly decoiling, contained 2.78 times in the diameter.
Microsculpture of exceedingly fine radial riblets, eight to twelve
between each pair of major ribs, crossed by barely visible spiral
riblets. Color white with numerous zigzag, reddish-brown
flammulations. Aperture ovate, strongly rounded above and at
umbilical margin, inclined about 15° from shell axis. Parietal barriers
3, extending posteriorly three-sixteenths of a whorl: form of parietals
as above in "Diagnosis." Columellar barrier a low, deeply recessed
thread, lying parallel to plane of coiling. Palatal barriers 4, extending
posteriorly about one-eighth whorl: lower 3 moderately high, slightly
recessed, with gradual anterior descension; 4th supraperipheral, a
weak, deeply recessed, threadlike trace. Height of lectotype 1.74 mm.,
diameter 3.76 mm.
Lectotype. — Marquesas Islands: Nukuhiva.
Collected by Andrew Garrett. BPBM 3437.
Range. — Nukuhiva, Marquesas Islands.
Paratypes. - BPBM 3437.
Material. — Marquesas (9 specimens, Zurich,
FMNH 116986): Nukuhiva (3 specimens, BPBM 3437).
Remarks. — Reported as being taken in rotting
wood from a mountain ravine, this was not found by
members of the Pacific Entomological Survey who
collected extensively on Nukuhiva. It may well be that
Taipidon marquesana was a lowland species that is
now extinct. The only additional specimens located
were in the Mousson collection (Zurich), misidentified
as T. analogica (Pease, 1870).
Differences from the very similar T. woapoensis
are covered in the discussion of that species. Quite
possibly they are only subspecifically separable, but
without additional material I accept Garrett's judg-
ment.
SYSTEMATIC REVIEW
327
ab
cd
FlG. 142. a-b, Taipidon anceyana (Garrett, 1887). Dominique (=Hivaoa), Marquesas. Lectotype. BPBM 3118; c-d, Taipidon marquesana
(Garrett, 1887). Nukuhiva, Marquesas. Lectotype. BPBM 3437. Scale lines equal 1 mm. Drawings by YK reproduced through the courtesy of the
Bernice P. Bishop Museum.
Taipidon anceyana (Garrett, 1887). Figure 142
a-b.
Pitys anceyana Garrett, 1887, Bull. Soc. Malacol. France, 4, pp.
19-20 — Dominique (= Hivaoa), Marquesas; Pilsbry. 1892, Man.
Conchol., (2), 8, p. 96.
Endodonta (Thaumatodon) anceyana (Garrett). Pilsbry, 189.3, op.
cit.. (2), 9, p. 26.
Diagnosis. — Shell very large, diameter 4.50-5.33 mm. (mean 4.96
mm.), with 5%-6 normally coiled whorls. Apex and early spire flat,
lower whorls descending somewhat more rapidly, last whorl
descending distinctly more rapidly, H/D ratio 0.435-0.463 (mean
0.453). Umbilicus widely open, broadly V-shaped, regularly decoiling,
contained 2.78-2.96 times (mean 2.89) in the diameter. Postnuclear
sculpture of prominent, sharply defined, protractively sinuated radial
ribs, 51-73 (mean 61.3) on the body whorl, whose interstices are 3-5
times their width. Microsculpture of very fine radial riblets, eight to
twelve between each pair of major ribs, crossed by exceedingly fine
and crowded spiral riblets that are barely visible under 96 x
magnification. Weak secondary spiral cording is occasionally visible
on shell base. Sutures impressed, whorls strongly rounded above and
on weakly shouldered basal margin, flattened and compressed
laterally above and below obtusely rounded periphery. Aperture
ovate, compressed laterally above and below periphery, inclined
about 15° from shell axis. Parietal barriers 2, extending posteriorly
less than three-sixteenths of a whorl: upper a high lamellar blade,
expanded and serrated above on posterior half, with gradual anterior
descension until terminal quarter of length; 2nd parietal equal in
height to 1st, slightly more expanded posteriorly, with more gradual
anterior descension, terminating beyond end of upper parietal.
Columellar barrier a high bladelike ridge, weakly expanded above,
slanting downwards from plane of coiling, abruptly descending
almost to lip margin. Palatal barriers 4, extending posteriorly one-
eighth whorl: lower basal in position, high and flattened above, with
rather sharp anterior descension to lip edge; 2nd and 3rd equal in
height to 1st, with progressively more gradual anterior descension;
4th supraperipheral, a moderately deeply recessed, V-shaped ridge,
much lower than other palatals.
The very wide umbilicus and presence of a
prominent columellar barrier at once separate Taipi-
don anceyana. The other Marquesan species with a
prominent columellar barrier, T. octolamellata, differs
in its narrower umbilicus, smaller size, and presence of
4 large palatals. Both T. woapoensis and T. marque-
sana differ in having the columellar reduced to a
threadlike trace. T. analogica and T. petricola differ in
their narrow umbilici and much more elevated spires.
328
SOLEM: ENDODONTOID LAND SNAILS
Description. - Shell very large, with 534 loosely coiled whorls.
Apex flat with repaired injury at end of embryonic whorls, lower
whorls descending gradually, last whorl more rapidly, H/D ratio
0.460. Embryonic whorls l'/z with very closely set radial riblets
crossing moderately widely spaced spiral ribs. Postnuclear whorls
with widely spaced, slightly protractively sinuated, lamellar radial
ribs, 69 on the body whorl, whose interstices are 3-4 times their
width. Microsculpture of very fine and closely spaced radial riblets,
eight to twelve between each pair of major ribs, microscopic spiral
riblets, and weak spiral cording on base of shell. Sutures moderately
deep, whorls strongly rounded above, somewhat flattened above and
below periphery, giving an obtuse angulation to the body whorl.
Umbilicus broadly V-shaped, contained 2.92 times in the diameter,
with slightly shouldered margin. Color light yellow-brown with
irregular, reddish flammulations. Aperture circular, slightly flattened
above and below periphery of body whorl, inclined about 15° from
shell axis. Parietal barriers 2, extending posteriorly about one-eighth
whorl: structure as in "Diagnosis." Columellar barrier a high
lamellate ridge, slanted downward from plane of coiling across weak
umbilical callus almost to lip edge. Palatal barriers 4, extending
posteriorly one-eighth whorl: lower 3 short and high: upper a
moderately prominent V-shaped ridge. Height of lectotype 2.30 mm.,
diameter 5.00 mm.
Lectotype. — Marquesas Islands: Dominique ( =
Hivaoa). Collected by Andrew Garrett. BPBM 3118.
Range. — Hivaoa, Marquesas Islands.
Paratypes. - BPBM 3118.
Material. — Marquesas (3 specimens, BPBM
3118).
Remarks. — Only Taipidon marquesana and T.
woapoensis approach the umbilical width of this
species. The large columellar barrier and only 2
parietals separate T. anceyana immediately. Probably
this is another lowland species that has become
extinct.
Taipidon analogica (Pease, 1870). Figure 143a-d.
Pithys analogica Pease, 1870, Jour, de Conchyl., 18, pp. 396-397 —
Marquesas.
Pitys analogica Pease, 1871, Proc. Zool. Soc. London. 1871, p. 454;
Garrett, 1887, Bull. Soc. Malacol. France, 4, p. 14.
Helix (Pithys) analogica (Pease), Pfeiffer, 1876, Monog. helic. viv.,
7, p. 257.
Helix (Endodonta) analogica (Pease), Tryon, 1887. Man. Conchol..
(2), 3, p. 63.
Endodonta (Thaiimatodon) analogica (Pease), Pilsbry, 1893, op.
cit.. (2), 9, p. 26.
Diagnosis. — Shell relatively large, diameter 3.97-5.26 mm.
(mean 4.36 mm.), with 6-7Vi tightly coiled whorls. Apex and spire
moderately elevated, slightly rounded above, body whorl descending
distinctly more rapidly. H/I) ratio 0.556-0.660 (mean 0.597).
Umbilicus relatively narrow, U-shaped, last whorl decoiling slightly
more rapidly, contained 3.65-4.14 times (mean 3.94) in the diameter.
Postnuclear sculpture of high, prominent, strongly protractively
sinuated radial ribs. 80-95 (mean 86.3) on the body whorl, whose
interstices are about twice their width. Microsculpture of fine radial
riblets, six to nine between each pair of major ribs, crossed by
exceedingly fine and crowded spiral riblets. with a secondary
sculpture of prominent, rather widely spaced spiral cords visible over
entire shell surface. Sutures impressed, whorls strongly rounded
above and on basal margin, almost evenly rounded on outer margin.
Aperture ovate, with evenly rounded outer margin, inclined about
15° from shell axis. Parietal barriers 2, extending posteriorly almost
one-quarter whorl: upper high and bladelike, strongly thickened and
serrated above on posterior three-quarters, with gradual anterior
descension until just before termination; 2nd parietal equally high
and expanded above on posterior three-eighths, with gradual anterior
descension to point beyond termination of upper parietal. Columellar
barrier a weak to moderately prominent threadlike trace or ridge,
reaching almost to lip margin or deeply recessed, generally without,
but occasionally with three threadlike accessory traces. Palatal
barriers 4, extending posteriorly more than one-eighth whorl: lower
basal in position, a high prominent lamellar ridge with sharp anterior
descension, or reduced to a threadlike trace that is deeply recessed;
2nd and 3rd high and bladelike, very slightly recessed within
aperture, with progressively more gradual anterior descension than
normal sized 1st palatal; 4th palatal supraperipheral, moderately to
strongly reduced in height, more deeply recessed, with very gradual
anterior descension.
The distinctly elevated spire, presence of promi-
nent secondary spiral cording, and relatively narrow,
U-shaped umbilicus of T. analogica at once separate
this species from the other Marquesan taxa. Of the
other Marquesan species with prominent secondary
spiral cording, T. semimarsupialis has the umbilicus
modified to form a brood chamber; T. centadentata
has the apertural barriers reduced to short traces on
the palatal wall; and the much smaller T. petricola
has a much narrower umbilicus and very crowded
radial ribbing.
Description. — Shell large, with 7'4 relatively tightly coiled
whorls. Spire moderately elevated, rounded above, last whorls
descending sharply, H/D ratio 0.660. Embryonic whorls ls/8, all
sculpture eroded. Remaining whorls with high, thin, protractively
sinuated, rather widely spaced radial ribs, 80 visible on the body
whorl, whose interstices are 2 or 3 times their width. Last third of
body whorl containing gerontic growth with ribbing reduced to
irregular growth lines. Microsculpture mainly eroded, obvious
remnants consisting of very fine radial riblets crossing narrow,
closely spaced spiral cords. Sutures well marked, whorls strongly
rounded above, very slightly flattened laterally. Umbilicus U-shaped,
contained 3.98 times in the diameter, last whorl decoiling more
rapidly, with angulately flattened margins. Color leached from shell
with only faint traces of a few irregular, reddish flammulations.
Aperture ovate, somewhat compressed laterally, inclined about 15°
from the shell axis. Parietal wall with 2 barriers, extending
posteriorly almost one-quarter whorl: upper lamellate for its entire
length, descending gradually for anterior half, expanded and serrated
above posteriorly; lower with anterior threadlike extension for
anterior third. Columellar barriers 2, upper a deeply recessed
threadlike ridge, the lower high and apically expanded, reaching
almost to lip margin. Two minor accessory threads are located near
the umbilical basal margin, one in position of lower palatal. Major
palatal barriers 3, lower 2 high and lamellate, extending about one-
eighth whorl, upper a slightly shorter, low ridge. Height of lectotype
3.50 mm., diameter 5.24 mm.
Lectotype. — Marquesas Islands. BPBM 115307 ex
W. H. Pease (MCZ 17260).
Range. Marquesas Islands (exact locality
unknown).
Material. -- Marquesas (4 specimens, BPBM
115307, ANSP 83209).
Remarks. -• The only material known of this
species is without exact locality data. No specimens
were obtained by Andrew Garrett in his collecting
during the 1880's or by the Bishop Museum Pacific
FIG. 143. a-d, Taipidon analogica (Pease, 1870). 0-6, Marquesas. Lectotype. BPBM 115307; c-d, Marquesas. BPBM 115291; e-f,
Taipidon semimarsupialis, new species. Mt. Ooumu, 4,050 ft.. Nukuhiva, Marquesas. Holotvpe. BPBM 96051. Scale lines equal 1 mm.
Drawings by YK reproduced through the courtesy of Bernice P. Bishop Museum.
329
330
SOLEM: ENDODONTOID LAND SNAILS
Entomological Survey in the 1920's and 1930's. Other
than the types, the only specimens available are ANSP
83209 (part of this set is BPBM 115291 and BPBM
164566), received from C. D. Voy as coming from the
Marquesas Islands. They (table XCIII) are smaller
(diameter 3.95-4.08 mm., mean 4.04 mm.), lower (H/D
ratio 0.550-0.600, mean 0.576), and have slightly
different apertural barriers (fig. 143d) than the types.
The former have 4 palatals, and the upper palatal is
much less reduced in size than is that of the lectotype
(fig. 143a). Certainly, they represent different popu-
lations, quite possibly different taxa. It is quite
possible that T. analogica may yet be discovered at
higher elevations on one of the islands.
In its reduction of the lower palatal in some
specimens and strong development of spiral cording, T.
analogica appears transitional between the more
generalized Taipidon and T. semimarsupialis.
GROUP OF Taipidon centadentata
Taipidon semimarsupialis, new species. Figures
139a-c; 143e-f.
Diagnosis. — Shell large, diameter 4.07-4.34 mm. (mean 4.23
mm.), with 6% - 7'/2 very tightly coiled whorls. Apex and spire dome-
shaped, lower whorls descending quite rapidly, H/D ratio 0.683-0.787
(mean 0.738). Umbilicus broadly open apically, U-shaped, flat-sided,
internally without sculpture, secondarily narrowed on last one and
one-quarter whorls to form a brood pouch, which is contained 4.92-
5.46 times (mean 5.25) in the diameter. Postnuclear sculpture of high,
narrow, rather crowded, slightly protractively sinuated radial ribs,
85-97 (mean 90.3) on the body whorl, whose interstices are 2-3 times
their width. Microsculpture of rather prominent radial riblets, three
to five between each pair of major ribs, crossed by spiral riblets that
are barely visible under 96 X magnification. Secondary micro-
sculpture of low, rather widely spaced spiral cords that fade out near
periphery. Sutures impressed, whorls almost evenly rounded on outer
margin, more sharply rounded on umbilical and columellar margins.
Aperture elongately ovate, with evenly rounded outer margin,
inclined about 10° from shell axis. Parietal barriers 2, extending
posteriorly to line of vision: upper slender and bladelike, weakly
expanded above on visible posterior two-thirds, with gradual anterior
descension; 2nd equal in height to 1st on expanded posterior half,
with rather sharp descension to an elevated threadlike ridge that
extends anteriorly beyond end of upper parietal. Columellar wall
smooth, without any barriers. Palatal barriers 4, extending
posteriorly about one-eighth whorl, upper greatly reduced: lower at
baso-columellar margin, high, slender, and bladelike, with rather
sharp anterior descension to lip edge; 2nd and 3rd progressively
slightly reduced in height, with more gradual anterior descension, 3rd
slightly more deeply recessed within aperture; 4th palatal subpe-
ripheral, a very faint, deeply recessed, threadlike trace.
The secondary narrowing of the umbilicus to form
a brood chamber in Taipidon semimarsupialis imme-
diately distinguishes it from all other Marquesan
species. Juvenile specimens can be recognized by the
absence of radial sculpture on the umbilical whorls
and the extreme elevation of the spire when compared
with other Taipidon.
Description. — Shell large, with 7'/2 very tightly coiled whorls.
Apex barely elevated, whorls of spire descending rapidly, producing a
globosely dome-shaped shell, H/D ratio 0.744. Embryonic whorls 1%,
sculpture of moderately widely spaced radial ribs crossed by
relatively narrow spiral ribs. Remaining whorls with nearly vertical,
lamellate radial ribs, 89 on the body whorl, whose interstices are 2-3
times their width. Microsculpture of very fine radial riblets crossed
by low, regular, secondary spiral cords. Secondary spiral sculpture
strong on base, weaker above periphery. Sutures relatively shallow,
whorls slightly shouldered above, somewhat flattened laterally.
Umbilicus widely opened internally, constricted by inward growth of
last 1V4 whorls to form a modified brood chamber. Remaining
opening nearly circular, contained 5.38 times in the diameter. Inner
walls of umbilicus without sculpture. Color light yellow-brown with
prominent, zigzag reddish flammulations. Aperture compressedly
ovate, nearly parallel to the shell axis, somewhat flattened basally.
Parietal barriers 2, extending to line of vision: both low sharp ridges,
2nd with anterior third a raised threadlike ridge. Columellar wall
without barriers. Palatal barriers 4, extending one-eighth whorl:
lower 3 relatively low and bladelike, slanting gradually across weak
apertural callus; upper palatal subperipheral, a deeply recessed low
threadlike ridge. Height of holotype 3.16 mm., diameter 4.25 mm.
Holotype. — Marquesas Islands: Nukuhiva, ridge
near summit of Mt. Ooumu, at 4,050 ft. elevation.
Collected on November 12, 1929, by members of the
Pacific Entomological Survey team. BPBM 96051.
Range. — Ridge near summit of Mt. Ooumu at
4,050 ft. elevation, Nukuhiva, Marquesas Islands.
Paratypes. - BPBM 96052.
Material. — Nukuhiva, ridge near summit of Mt.
Ooumu at 4,050 ft. elevation (3 specimens, BPBM
96051-2).
Remarks. — Brood chamber formation in Taipi-
don semimarsupialis is quite different from the
pattern seen in Libera or Gambiodonta. As in all
species with brood chambers, the apical part of the
umbilicus is widely open with narrowing a secondary
phenomenon occurring near the aperture. About 1V4
whorls behind the aperture, the entire columellar wall
curves inward, tracing a narrowing circle, until the
restricted external opening is formed. There is no
marked alteration of the columellar wall or baso-
columellar angle. In Gambiodonta the narrowing
occurs over a comparatively short distance and in both
Libera and Gambiodonta there are considerable
modifications in the columellar wall and baso-colum-
ellar angle. Taipidon semimarsupialis also is unusual
in that the entire columellar wall has no trace of
radial ribbing.
Without study of much more material, it will be
impossible to determine the homologies of the apertur-
al barriers. I have interpreted them as 4 palatals, but
it is quite possible that the lower palatal represents a
displaced and enlarged columellar. In this view, the
ribless functioning columellar wall could be inter-
preted as a displaced section of the parietal wall, such
as is found in Planudonta (fig. 146), with the original
columellar wall deflected downward and outward to
accomodate the demands of a dome-shaped coiling
pattern and secondary narrowing of the umbilical
opening. If the above structural alterations occurred,
then what I have called the 1st palatal is really the
columellar. While this is probably correct, the
conservative course has been adopted and the barriers
are referred to as palatals.
SYSTEMATIC REVIEW
331
The name semimarsupialis emphasizes the differ-
ent and seemingly incomplete pattern of brood
chamber formation when compared with Libera or
Gambiodonta. Despite the drastic shape and coiling
changes that accompanied brood chamber formation,
T. semimarsupialis unquestionably is closely related to
T. analogica and T. centadentata.
The multiplication of radular teeth in T. semi-
marsupialis is less pronounced than in T. centaden-
tata, but the presence of about 26 teeth per half row is
almost 50 per cent greater than the norm for
Endodontidae. Otherwise the anatomy is without
unusual features, except for the diaphragm serving as
origin for the penial retractor, a condition shared with
T. centadentata.
Description of soft parts. — Based on fragmentary, extracted
and torn specimens.
Body color yellow-white, no darker markings.
Mantle collar (MC) narrow, not thickened, a faint glandular
extension onto lung roof into which principal pulmonary vein
merges. Pneumostome and anus (A) normal.
Pallial region (fig. 139c) about 12.8 mm. long, very narrow. Lung
roof clear, without granulations. Kidney (K) about 2 mm. long,
tapering anteriorly, rectal arm 0.6 mm. long, posterior end broadly
rounded, thin, with loop of intestine lying under it. Ureter (KD)
typical, opening next to hindgut just above anterior end of rectal
kidney arm. Heart (H) about 1 mm. long, not parallel to hindgut.
Principal pulmonary vein (HV) typical. Hindgut (HG) extending
about one-eighth whorl above apex of pallial cavity.
Ovotestis not available for study. Hermaphroditic duct (fig.
139a, GD) very long and slender apically, moderately expanded in
central and anterior portion, reflexing abruptly before entering
carrefour. Albumen gland (GG) elongated, narrow, with relatively
large acini. Talon (GT) tapered with moderately expanded head,
rather short, carrefour not clearly differentiated in available
material. Prostate (DG) with two rows of rather large, short acini
opening into a narrow tube. Uterus (UT) with upper glandular zone
clearly differentiated, upper tubular section three-quarters length of
prostate, lower quarter the typical expanded chamber with heavily
glandularized walls.
Vas deferens (VD) lightly bound to penioviducal angle, entering
penis about 0.4-0.5 mm. below head, opening between pilasters.
Penial retractor (PR) arising from diaphragm, inserting on head of
penis without a fleshy extension. Penis (P) about 4.9-5.25 mm. long,
only slightly tapering anteriorly, internally (fig. 139b) with two
pilasters, one short and slender, the other high, slender and
complexly folded apically, becoming low and rounded after apical
third, continuing to last quarter where it becomes swollen and
higher. Lower two-thirds of penis with pustulose glandular devel-
opment, somewhat sculptured by transverse rugosities extending
from pilaster. Atrium (Y) short and wide.
Free oviduct (UV) equal in length to prostate-uterus, very
slender and not tapering. Spermatheca (S) with elongately oval head
lying next to albumen gland, shaft slightly swollen basally, entering
on penioviducal angle.
Free muscle system without unusual features except very-
elongated parts.
Jaw about 50,u wide, composed of partly fused, elongately
rectangular plates about 4-5 times as long as wide, only fragments
successfully mounted. Central area fused.
Radula with more than 115 rows, centrals 6-8,u wide, 8,u long,
tricuspid. Laterals 13-15, with 10-13 marginals, no sharp transition.
Shape of teeth differing from T. centadentata only in having the
lateral ectocone smaller.
(Based on BPBM 96051-2, extracted and partly fragmented
specimens. )
Taipidon centadentata, new species. Figures
139d-f; 144.
Diagnosis. — Shell very large, diameter 4.30-5.56 mm. (mean 4.73
mm), with 5'/2 - 6% rather tightly coiled whorls. Apex and spire
moderately and almost evenly elevated, somewhat rounded or
occasionally flattened above, last whorl descending more rapidly,
H/D ratio 0.539-0.633 (mean 0.577). Umbilicus relatively narrow, U-
shaped, slightly and regularly decoiling, contained 3.82-4.77 times
(mean 4.24) in the diameter. Postnuclear sculpture of high,
prominent, crowded, protractively sinuated radial ribs. 83-137 (mean
98.9) on the body whorl, whose interstices are 2-3 times their width.
Microsculpture of fine radial riblets, five to eight between each pair
of major ribs, crossed by barely visible, extremely crowded spiral
riblets, with a secondary spiral cording that is strongest on base of
shell and fades out near periphery. Sutures impressed, whorls
strongly rounded above and on umbilical margin, slightly compressed
laterally. Aperture ovate, slightly compressed laterally below
periphery, inclined about 10° from shell axis. Major parietal barriers
2. extending posteriorly beyond line of vision, with fifteen to twenty
accessory threadlike traces: upper parietal a narrow, relatively low,
bladelike ridge, weakly expanded and serrated above posteriorly,
with rather sharp anterior descension; 2nd slightly reduced in height,
with more gradual anterior descension, terminating beyond end of
upper parietal. Accessory traces located five to eight above upper
parietal, four to six between two major parietals, and six to eight
below 2nd parietal. Columellar and palatal walls with numerous,
very short, threadlike traces located on top of a raised callus that
extends less than one-eighth whorl and is moderately recessed within
aperture. Juvenile specimens with one basal and one subperipheral
palatal trace distinctly elevated (fig. 144a); many adults with
subperipheral trace still distinctly higher than the remaining ones.
The short and numerous threadlike traces on the
palatal wall immediately separate Taipidon centaden-
tata from all other Marquesan species except Plan-
udonta intermedia. That species, also found on
Nukuhiva, has a depressed spire, very widely open
umbilicus, and the threadlike traces extend well into
the aperture. Differences from other Pacific Island
species with reduced apertural barriers are given below
under remarks.
Description. — Shell large, with 6"2 normally coiled whorls. Apex
and spire moderately elevated, rounded, last whorl descending a little
more rapidly, H/D ratio 0.591. Embryonic whorls 1%, sculpture of
very fine, widely spaced radial riblets crossing much finer, rather
closely spaced spiral cords. Postnuclear whorls with high, lamellate,
slightly protractively sinuated radial ribs, 96 on the body whorl,
whose interstices are 2-4 times their width. Many radial ribs with
periostracal extensions. Microsculpture of fine radial riblets and
barely visible spiral riblets crossed by broadly rounded, low, closely
set spiral cords that are stronger in the umbilical and basal regions
than on upper portions of the whorls. Sutures relatively shallow,
whorls broadly rounded above without obvious flattenings. Umbil-
icus narrowly U-shaped, slightly and regularly decoiling, contained
4.08 times in the diameter. Aperture ovate, inclined about 5° from
shell axis. Major parietal barriers 2, extending beyond line of vision,
with seventeen accessory threadlike traces: upper a low, lamellate
ridge, rounded and minutely serrated above; lower a prominent
threadlike ridge. Columellar and palatal walls with a relatively wide,
rather deeply recessed apertural callus, on which are numerous
threadlike ridges. Height of holotype 3.09 mm., diameter 5.23 mm.
Holotype. — Marquesas Islands: Nukuhiva, ridge
of Mt. Ooumu at 3,900 ft. elevation. Collected on dead
leaves and other debris on November 13, 1929, by
332
SOLEM: ENDODONTOID LAND SNAILS
FIG. 144. a-c, Taipidon centadentata, new species. Mt. Ooumu,
3,900 ft., Nukuhiva, Marquesas, a, juvenile paratype. BPBM 96099;
b-c, Holotype. BPBM 96096. Scale lines equal 1 mm. Drawings by
YK reproduced through the courtesy of Bemice P. Bishop Museum.
members of the Pacific Entomological Survey. BPBM
96096.
Range. - Mt. Ooumu, 3,900-4,050 ft. elevation,
Nukuhiva, Marquesas Islands.
Paratypes. — Same as list of material.
Material. — Nukuhiva: ridge of Mt. Ooumu at
3,900 ft. elevation (43 specimens, BPBM 96096-101);
ridge near summit of Mt. Ooumu at 4,050 ft. elevation
(13 specimens, BPBM 96053-6).
Remarks. — At least partial reduction of the
apertural barriers to numerous threadlike ridges has
also taken place in the Marquesan Planudonta
intermedia; the Tubuaian and Rurutuan Australdonta
radiella; the Hawaiian Nesophila; and in the Rapan
Opanara megomphala. In A. radiella and Nesophila
the barriers are restricted to the parietal wall, while in
O. megomphala and P. intermedia they extend on all
walls well past the line of vision. Thus, Taipidon
centadentata differs from both types in having
elongated threadlike barriers on the parietal wall, and
very short and limited ones on the columellar and
palatal walls. These should be considered parallel
developments in unrelated stocks. The form and
sculpture of T. centadentata clearly ally it to the
group of T. analogica, despite its highly modified
apertural barriers.
The name centadentata is appropriate not only
for the many apertural barriers, but also for the large
number of radular teeth. The 22-23 laterals and 16-17
marginals represent the largest count found in the
Endodontidae examined to date. As mentioned above
(p. 317), the penial differences between T. semi-
marsupialis and T. centadentata parallel the differ-
ence between the Hivaoa sympatric pair, T. fragila
and T. varidentata, with one species having the
pilasters partly broken into beads. Presumably this
serves to bolster specific separation.
Description of soft parts. — Foot and tail narrow, quite
elongated, rounded behind, not tapering. Sole undivided, pedal
grooves relatively low on foot, pedal much more prominent than
suprapedal, no caudal horn or middorsal groove present. Slime
network prominent, irregular in shape and relatively small divisions.
Head retracted in all available specimens.
Body color yellow-white, no darker markings.
Mantle collar (MC) without lobes or glandular extension into
pallial cavity. Pneumostome and anus normal.
Pallial region (fig. 139d) with lung roof clear, no granulations.
Kidney (K) about 2.11 mm. long, rectal arm 1.12 mm. long, base
evenly rounded. Ureter (KD) typical, reflexing up rectal kidney arm
and opening next to anterior tip of same, slightly removed from
hindgut. Heart (H) about 1.1 mm. long, slightly angled from hindgut
axis. Principal pulmonary vein (HV) narrow, extending almost to
edge of mantle collar, unbranched. Hindgut (HG) typical.
Ovotestis (fig. 139e, G) with widely spaced clumps of palmately
clavate alveoli, with typical orientation. Hermaphroditic duct (GD)
somewhat irregularly expanded, not coiled, slightly iridescent,
narrowing abruptly before reflexing into carrefour. Albumen gland
(GG) narrow and elongated, extending apically past tip of talon,
with rather large acini. Talon (GT) long, gradually tapering, with
moderately expanded head, carrefour region structure not deter-
SYSTEMATIC REVIEW
333
mined. Prostate (DG) equal in length to uterus, of very slender acini,
two rows, opening into very narrow duct. Uterus (UT) bipartite,
expanded lower chamber not extending past base of prostate.
Vas deferens (VD) a continuation of prostatic duct, entering
penis laterally between weak apical pilasters, about 0.67 mm. below
penis head. Penial retractor (PR) inserting on fleshy head of penis,
origin from diaphragm. Penis (P) about 4.3 mm. long, only slightly
expanded just below vas deferens insertion, internally (fig. 139f) with
two pilasters that are greatly reduced above vas deferens entrance,
becoming partly split into elongated, globular beads in midsection,
more typical basally, with a median pustulose zone in wall of penis.
Atrium (Y) short.
Free oviduct (UV) short, narrow, only slightly tapering.
Spermatheca (S) with oval, very large head, inserting into
penioviducal angle.
Free muscle and digestive systems not studied.
-Jaw about 50u wide, individual plates 4-5 times as long as wide,
central area fused, outer plates partly fused.
Radula with centrals about 6fi long, 4fi wide, more than 100 rows
with 22-23 laterals and 16-17 marginals, the latter with square basal
plates. Laterals with endocone appearing after 20th lateral, ectocone
progressively larger. Outer marginals with variously split cusps.
Ectocone on laterals quite prominent.
(Based on BPBM 96053, one adult 4.64 mm., in diameter, and
BPBM 96096, several fragmentary adults.)
GROUP OF Taipidon varidentata
Taipidon varidentata, new species. Figures 138g-
h; 145c-d.
Diagnosis. — Shell rather small, diameter 3.48-4.01 mm. (mean
3.68 mm. ), with 47/8 - 5172 normally coiled whorls. Apex and spire
slightly and evenly elevated, last whorl descending much more
rapidly, H/D ratio 0.457-0.640 (mean 0.495). Umbilicus widely V-
shaped, regularly decoiling, contained 2.98-3.43 times (mean 3.21) in
the diameter. Postnuclear sculpture of narrow, prominent, crowded,
vertically sinuated radial ribs, 115-179 (mean 147.0) on the body
whorl, whose interstices are 2-4 times their width. Microsculpture of
fine radial riblets, four to six between each pair of major ribs, crossed
by exceedingly fine and crowded spiral riblets. Sutures deep, whorls
strongly rounded above and on basal margin, with evenly rounded
outer margin. Aperture nearly circular, with evenly rounded outer
margin, lying almost parallel to shell axis. Parietal barriers 2.
extending posteriorly less than three-sixteenths of a whorl: upper a
high slender blade, weakly expanded above on posterior two-thirds,
with gradual anterior descension; 2nd reduced in height, more
broadly expanded above on posterior two-thirds, with gradual
anterior descension to point well in front of upper termination.
Columellar wall with 1 (75 per cent I or 2 (25 per cent) prominent
barriers: major columellar located at baso-columellar margin, a high
crescentic blade, somewhat flattened above, with abrupt anterior
descension almost to lip margin; 2nd, when present, reduced in
height and located above major columellar with equally abrupt
anterior descension. Palatal barriers variable in number (3-6) and
height, mainly high crescentic blades, sometimes flattened above,
clustered along lower palatal and basal lip margins, sometimes with
a minute threadlike supraperipheral trace present.
The short crescentic palatal barriers that cluster
near the basal margin immediately separate Taipidon
fragila and T. varidentata from the other Marquesan
species. The former differs in its flat spire, much
narrower umbilicus and extremely fine ribbing.
Description. — Shell of less than average size, with 5'/2 relatively
loosely coiled whorls. Apex and upper spire slightly elevated, body
whorl descending much more rapidly, H/D ratio 0.512. Apical whorls
1%, sculpture eroded outside, internally showing relatively widely
spaced radial riblets crossed by smaller, widely spaced spiral riblets.
Remaining whorls with very narrow, lamellate, closely set, vertically
sinuated, radial ribs, 179 on the body whorl, whose interstices are
about twice their width. Microsculpture of three to seven radial
riblets between each pair of major ribs and barely visible spiral
riblets. Sutures relatively deep, whorls strongly rounded above and
on baso-columellar margin, evenly rounded laterally. Color light,
yellowish-olive-brown with faint, irregular, reddish flammulations
above periphery. Aperture nearly circular, strongly rounded above
and slightly flattened on columellar margin. Parietals barriers 2,
extending about one-quarter whorl: both high and lamellate for
entire length, upper bladelike, lower more expanded and minutely
serrated above. Columellar and palatal walls with 6 barriers: lower 5
very short, high and crescentic, reaching apertural margin; first 3
grouped at columellar and basal margin, abruptly descending
anteriorly; 4th located midway up lower palatal wall, descending
more gradually anteriorly; 5th slightly subperipheral in position, a
more ridgelike and lower barrier; 6th a minute, supraperipheral,
threadlike trace. Height of holotype 2.04 mm., diameter 3.98 mm.
Holotype. — Marquesas Islands: Hivaoa, ridge of
Mt. Temetiu at 3,860 ft. elevation. Collected from dead
leaves on December 27, 1930, by members of the
Pacific Entomological Survey. BPBM 104635.
Range. — Hivaoa Island, Marquesas Islands.
Paratypes. — See list of material.
Material. — Hivaoa: ridge of Mt. Temetiu at 3,860
ft. elevation (1 specimen, BPBM 104635); Matauuna,
north of Mt. Temetiu summit at 3,800 ft. elevation (1
specimen, BPBM); valley of Matauuna at 2,800 ft.
elevation (1 specimen, BPBM 98763); crest to north of
Mt. Temetiu at 2,615 ft. elevation (1 specimen, BPBM
94799).
Remarks. — Only four specimens, each from a
slightly different locality, are known of Taipidon
varidentata. Although similar in size, shape, and
sculpture, they differed widely in the form of the
columellar and palatal barriers. The situation in the
type is described above. The remaining three examples
show: 1) Matauuna at 3,800 ft. elevation: 4 barriers
grouped near columellar and basal margin with 1st
slightly reduced and 3rd greatly reduced in size; plus
another located one-fourth way up palatal wall; 2)
Matauuna Valley at 2,800 ft. elevation: 1 columellar
thread parallel to the plane of coiling; 3 equal-sized
barriers grouped at columellar and basal margin; 3)
crest north of Mt. Temetiu at 2,615 ft. elevation: 4
barriers grouped near columellar and basal margins
with 1st relatively reduced and the 3rd slightly
reduced in size; one located midway up palatal wall;
one subperipheral; and one small trace located above
periphery.
The latter specimen is quite similar in barrier
location to that of the type, but the others varied
considerably. Unfortunately, only single specimens are
known from each locality, and we have no data as to
how characteristic the palatal barrier structures may
be of any single population.
T. varidentata and T. fragila might be altitudinal
replacements, with the former only found below
334
SOLEM: ENDODONTOID LAND SNAILS
I-
ab
cd
H
FIG. 145. a-b, Taipidon fragila, new species. Mt. Temetiu, 3,980 ft., Hivaoa, Marquesas. Holotype. BPBM 98652; c-d, Taipidon uaridentata,
new species. Mt. Temetiu, 3,860 ft., Hivaoa, Marquesas. Holotype. BPBM 104635. Scale lines equal 1 mm. Drawings by YK reproduced through
the courtesy of Bernice P. Bishop Museum.
3,900 ft. elevation and the latter only taken above
3,900 ft. So few records are involved, that this more
probably is an accident of collecting.
Description of soft parts. — A single retracted, only partly
extracted animal was available and yielded data only in respect to
terminal genitalia.
Prostate (fig. 138g, DG) about 2 mm. long, two rows of large
acini opening into a slender tube appressed to margin of clearly
bipartite uterus (UT). Latter typical in structure and internal
texture. Free oviduct (UV) sharply narrowed with finer internal
pustulations than in uterus. Spermatheca (S) with head not
available, shaft inserting directly into penioviducal angle. Vas
deferens (VD) entering penis about 0.4 mm. below apex.
Penis (P) about 2.5 mm. long with a slender fleshy extension to
head, slender apically, gradually enlarging until just before basal
area which is swollen, then constricting sharply to long atrium (Y).
Internally (fig. 138h) penis with two pilasters (PP) that merge
apically, one short and slender, the other very high, slender and
complexly folded, becoming broadly expanded and merging into
pustulose region occupying swollen portion of penis.
Jaw about 45,u wide, composed of broadly rectangular plates,
about 18 in entire jaw. Length of jaw about 240ji.
Radula fragmented in mounting. Central tricuspid, mesocone
much larger than ectocones and only slightly shorter than basal
plate, about 8fi wide and lO/i long. Laterals 7, with progressively
larger ectocone, endocone appearing only on last lateral or first
marginal. Marginals about 13, basal plates becoming square,
mesocone narrowing and shortening, ectocone splitting in two on
outer teeth, endocone remaining slightly shorter than mesocone.
About 82 rows in mounted specimen.
(Based on BPBM 94799, one extracted individual.)
Taipidon fragila, new species.
145a-b.
Figures 138e-f;
Diagnosis. — Shell small, diameter about 3.36 mm., with 4%
normally coiled whorls. Apex and early spire slightly depressed or
SYSTEMATIC REVIEW
335
flat, body whorl descending quite rapidly, H/D ratio 0.439.
Umbilicus very narrow, U-shaped, last whorl decoiling much more
rapidly, contained about 4.96 times in the diameter. Postnuclear
sculpture of very fine, crowded, lamellate, protractively sinuated
radial ribs, 101-133 (mean 122.3) on the body whorl, whose interstices
are 3-4 times their width. Many ribs have long periostracal
extensions. Microsculpture of very fine radial riblets, three to five
between each pair of major ribs, with barely visible traces of
extremely fine secondary spiral riblets. Sutures relatively shallow,
with evenly rounded outer margin, aperture ovate, with evenly
rounded outer margin, inclined about 5° from shell axis. Parietal
barriers 1 (60 per cent), or 2 (40 per cent), extending slightly more
than one-eighth whorl: upper a low lamellate ridge, weakly expanded
and serrated above on posterior three-quarters, with gradual anterior
descension; 2nd, when present, a reduced threadlike ridge, extending
slightly beyond termination of upper parietal. Columellar wall with
single threadlike to elevated ridgelike, very short barrier, with rather
sharp anterior descension almost to lip edge. Palatal wall with one to
three traces clustered on basal and lower palatal margins: traces all
much less than one-eighth whorl in length, very low, variable in
height, usually only one present, but variable in position.
The reduced size and number of apertural bar-
riers, flat or depressed apex and early spire, and much
narrower umbilicus immediately separate Taipidon
fragila from the otherwise very similar T. varidentata.
Other Marquesan species have much larger and more
numerous apertural barriers, thicker shell, and much
stronger radial sculpture.
Description. — Shell small, with 4% loosely coiled whorls. Apex
distinctly depressed below whorls of spire, last whorl descending
rapidly, H/D ratio 0.539. Embryonic whorls l7/s, sculpture eroded
externally, visible inside umbilicus as typical microradial and
microspiral sculpture. Remaining whorls with low, rounded slightly
protractively sinuated radial ribs, 133 on the body whorl, whose
interstices are 2-3 times their width. Microsculpture of relatively
large, widely spaced radial riblets, three to four between each pair of
major ribs, with barely visible microspirals. Sutures relatively
shallow, whorls evenly rounded. Umbilicus narrowly U-shaped,
contained 4.96 times in the diameter, last whorl decoiling more
rapidly. Color greenish-yellow with irregular, reddish flammulations
above periphery. Aperture large, circular, nearly parallel to the shell
axis. Parietal wall with single, almost medial, low barrier extending
slightly more than one-sixteenth of a whorl. Columellar and basal
lips with two small ridgelike barriers and a very faint trace between
them. Height of holotype 1.81 mm., diameter 3.36 mm.
Holotype. — Marquesas Islands: Hivaoa, ridge of
Mt. Temetiu at 3,980 ft. elevation. Collected from dead
leaves on December 12, 1929, by members of the
Pacific Entomological Survey. BPBM 98652.
Range. — Hivaoa Island, Marquesas Islands.
Paratypes. — See list of material.
Material. — Hivaoa: ridge of Mt. Temetiu at 3,980
ft. elevation (2 specimens, BPBM 98652); same area at
4,160 ft. elevation (1 specimen, BPBM 115704);
Tenatinaei, Feani Ridge at 3,905 ft. elevation in dry
moss (7 specimens, BPBM 115693).
Remarks. — The type is the only adult whole
specimen of this very fragile, thin-shelled species. The
remaining adult specimens range from broken to
smashed, including one live collected example whose
shell literally collapsed of its own weight. While rib
counts were made on three specimens, only one adult
example could be measured.
The size and shape of the aperture, sunken apex,
broad body whorl, and fine ribbing immediately
characterize Taipidon fragila and separate it from all
other Marquesan species. At first glance, it seems to be
a variation of T. varidentata from the same localities,
but the relative whorl and umbilical width, different
spire shape and reduced barriers in T. fragila are
constant.
Of greater significance is the difference in penial
structure. The much shorter (1.5 mm.) penis of T.
fragila has the major pilaster broken up into elongated
lumps (fig. 138f), while in T. varidentata the longer
(2.5 mm.) penis has the major pilaster simple in
structure (fig. 138h). Exactly the same pattern of
variation is seen in the Nukuhiva sympatric species, T.
semimarsupialis and T. centadentata (fig. 139b, f), one
having a smaller penis with pustulose pilaster, the
other a larger penis with simple pilaster.
Description of soft parts. — A single extracted specimen
available, partly broken.
Pallial region typical, kidney about 1.38 mm. long, rectal arm
0.79 mm., ureter and heart typical.
Ovotestis of rather tightly compacted clumps of palmately
clavate acini lying transversely to Columellar axis, less interspersed
with digestive gland than in Taipidon centadentata. Hermaphroditic
duct, albumen gland and talon broken off in handling, not
illustrated. Talon as in Planudonta concava (fig. 147c). Prostate (fig.
138e, DG) short, about 1 mm. long, with large acini in one or two
rows. Uterus (UT) bipartite, extending only slightly below end of
prostate. Free oviduct (UV) typical both internally and externally.
Vas deferens (VD) entering penis just below apex to one side of
pilaster (fig. 138f). Penial retractor origin unknown, inserting onto
fleshy head of penis proper. Latter not sharply differentiated
externally. Penis (P) about 1.50 mm. long, swollen apically, tapering
rapidly on lower half, internally (fig. 138f) with a large pilaster
occupying upper two-thirds that is partly divided into elongated
lumps, with a smaller pilaster in lower portion and a reduced
pustulose zone just before basal narrowing. Spermatheca (S)
inserting on penioviducal angle. Atrium (Y) short.
Jaw about 50fi wide, of rectangular, slightly over-lapping plates,
11 in a half jaw, each plate about 3 times as long as wide.
Radula with about 105 rows, central about 8^1 wide, 10-11/i long,
tricuspid, mesocone only slightly larger than ectocones, all cusps
much shorter than basal plate. Laterals about 10/x square, 7 or 8 in
number, transition to marginals in one or two teeth, mainly by
shortening of basal plate. Marginals 9-10, with endocone becoming
larger than mesocone, both longer than basal plate, often by 3rd or
4th mesocones and ectocones weakly splitting, outer marginals with
square basal plate, endocone only slightly larger, mesocone and
ectocone bi- or tricuspid.
(Based on BPBM 115704, an extracted and broken individual.)
Genus Planudonta, new genus
Large Endodontidae with typical apical and microradial sculp-
ture, secondary microsculpture found only in intermedia.
Postnuclear sculpture of high, prominent, rather widely spaced
(ribs/mm. 3.61-6.54), slightly to strongly protractively sinuated radial
ribs, 44 -84 on the body whorl. Apex and early spire slightly
(subplanula) to deeply (concava) sunken below level of penultimate
whorl, last whorl descending rapidly (except in subplanula). Whorls
more than 6 (except matauuna), tightly coiled. Umbilicus broadly V-
shaped to cup-shaped, regularly decoiling, with upper one-quarter to
one-half of each umbilical whorl having drastically altered ribbing
336
SOLEM: ENDODONTOID LAND SNAILS
(fig. 146a). Parietal barriers 2. short to very long, without any traces
(subplanula and concava) or with a few (matauuna} to many
(intermedia) accessory traces. Columellar wall without barriers; with
two small barriers in matauuna; or with numerous traces in
intermedia. Palatal barriers absent in concava; 3 in subplanula and
matauuna; many traces in intermedia. Anatomy only partly known.
Penial retractor arising from columellar muscle, inserting directly
onto fleshy extension of penis head. Vas deferens entering penis well
below head. Penis internally with two pilasters, variously modified,
and a pustulose zone in central region. Jaw with or without partial
fusion of central plates. Radular teeth typical in structure and
number.
Type species. — Planudonta concaua, new species.
In possessing the fleshy extension to the penis
head and the well-developed pustulose glandular zone
in the central portion of the elongated penis, the
species of Planudonta clearly are related to Taipidon.
A fleshy extension to the penis head also is developed
in various Rapan taxa (Opanara, figs. 96, 97, and
Orangia, fig. 121) and the Austral Island Australdonta
(fig. 125), but is absent from other Endodontidae.
Other anatomical features, so far as are known, show
no unusual structure.
Unfortunately, only five specimens are known of
this genus, four from Nukuhiva and a broken shell
from Hivaoa. Differences are so large that description
of four species is necessary. Undoubtedly, adequate
collecting would have revealed additional species.
Planudonta differs from Taipidon in its patterns
of coiling. It might be polyphyletic in origin. In giving
it generic level recognition, I am influenced by the
great extent of the single change and the degree to
which it has altered the basic shell pattern. The
growth pattern of Planudonta is not duplicated
elsewhere in the Endodontidae. Extra-limital flat-
spired species include the Hawaiian Cookeconcha
decussatulus, C. lanaiensis, C. ringens, C. hystricellus,
and C. jugosus; the nominate race of the Society
Island Nesodiscus obolus; and the Palau Island
Aaadonta kinlochi. Except for the Nesodiscus, which
is modified for brooding the eggs in the umbilicus, all
have only moderately open umbilici, with mean D/U
ratios of 2.48 - 3.81 (average 3.13). Those extra-limital
species with distinctly depressed apices — the Ha-
waiian Cookeconcha hystrix and C. stellulus; Rapa
Island Opanara depasoapicata; Mangarevan Anceyo-
donta alternata; and Society Island Mautodontha
aoraiensis — have D/U ratios of between 2.72 and 3.10
(average 2.91). In contrast, the species of Planudonta
have very widely open umbilici with D/U ratios of 1.68
- 2.07 (average 1.85). Taipidon fragila does have the
apex depressed, but is an obvious relative of T.
varidentata.
Not only is the umbilicus very wide, but the
internal sculpture is quite unusual (fig. 146a). For
nearly the upper one-quarter to one-half of each whorl
there is no trace of major or microradial sculpture, but
only irregular growth striae. Normal growth pattern
involves deposition of a smooth callus over the parietal
wall, either after partial resorption of the ribbing or
FIG. 146. Umbilical sculpture and origin in Planudonta: a,
umbilical sculpture in Planudonta concai'a. Holotype. BPBM 96102;
b-e, hypothesized intermediate stages in origin of this sculptural
pattern. (MM).
SYSTEMATIC REVIEW
337
covering the ribbing on the preceding whorl. A sudden
change in growth pattern that involved lowering the
apex and simultaneously widening and making the
umbilicus shallower could move part of the parietal
callus growth outward and downward below the edge
of the preceding whorl (fig. 146b). This would produce
the sculptural alteration found in the umbilicus of
Planudonta. Since the ribbing in the umbilicus would
have no obvious special function, there would not be
selection pressure for extension of the ribbing. While
Planudonta undoubtedly is derived from Taipidon, the
retention of the peculiar umbilical sculpture does not
have any necessary implications as to the time of
origin.
The umbilical alterations and depression of the
spire are linked characters caused by the major change
in coiling pattern. While the probability of such a
major change occurring more than once is low, it must
be considered. At first glance, the changes in apertural
barriers suggest multiple origins. Planudonta concava
has lost all but the parietals, while P. intermedia and
P. matauuna have accessory traces. The latter are
present in Taipidon petricola, much as in P. ma-
tauuna, but the palatal traces in T. centadentata are
very short and those in P. intermedia extend beyond
the line of vision. Only P. subplanula has relatively
"normal" barriers. Actually, a progression from normal
barriers to traces, then reduction and elongation of all
palatal and columellar barriers to traces, and finally a
loss of the palatals and columellar is a logical sequence
of changes. Such a change is seen in the three
Nukuhiva species, P. subplanula, P. intermedia, and P.
concava, which also show a progressive depression of
the spire (almost flat to deep), concomitant increase
in the ribless portion of the umbilical whorls, and
decrease in umbilical depth. It is not possible to relate
the fragmentary Hivaoa species, P. matauuna, to this
series. Under these circumstances, I have no hesitation
in considering these species a monophyletic series.
Other variation is comparatively minor. The ribs
are quite prominent and weakly to strongly protrac-
tive. Spacing (table XCIV) is variable, the change
within P. subplanula being larger than the differences
between the species. Only P. intermedia shows traces
of secondary spiral cording. Diameter at four and five
whorls, measured from the apex to the suture, also
shows more variation within P. subplanula than
between the other species (table XCIV).
As would be expected, the genital differences
between the essentially sympatric P. intermedia (fig.
147b) and P. concava (fig. 147d), both taken within
150 ft. elevation on Mt. Ooumu, are greater than the
differences between P. subplanula (fig. 147g) and P.
intermedia.
Except for the single shell of P. subplanula from
the Tovii region of Nukuhiva at 200 ft. elevation, all
available material was taken at above 3,400 ft.
elevation. Quite probably Andrew Garrett did not
TABLE XCIV. - RIB SPACING AND WHORL DIAMETER IN PLAHUDONTA
Name
subplanula
Holotype
BPBM 98252
intermedia
Holotype
concava
Holotype
matauuana
Ribs Ribs/mm.
34
44
5.85
4.00
69
Holotype
3.79
3.61
4 whorl
diameter
in mm.
1.15
1.41
1.05
1.25
1.48
5 whorl
diameter
in mm.
1.64
2.01
1.51
1.84
2.01
collect much above 2,000 ft. (Taipidon woapoensis}.
His failure to collect this group has no significance. All
records, except for the type or P. subplanula, indicate
collection "under dead leaves." While the latter was
recorded as "collected on ferns or shrubs," I am not
convinced that this is an arboreal species. I suspect
that the entomologist who collected this specimen
picked it up from the ground and put it in a vial with
the large and conspicuous Philonesia ordinaria taken
from ferns and shrubs at the same station (see H. B.
Baker, 1940, p. 153). I am very doubtful that P.
subplanula will be found to leave the ground stratum.
Although forest destruction in the Marquesas has
proceeded to a great extent, it is very possible that
material of Planudonta can still be found at high
elevations in patches of native forest.
KKY TO THK GENUS Planudonta
\. Barriers present on palatal wall 2
Barriers absent from palatal wall; diameter more than 5.25 mm.
Planudonta concava, new species
2. Several accessory traces present on parietal wall 3
No accessory traces present on parietal wall.
Planudonta subplanula, new species
3. Ribbing crowded, ribs/mm. 6.50; many palatal traces extending
beyond line of vision; Nukuhiva.
Planudonta intermedia, new species
Ribbing widely spaced, ribs/mm. 3.60; no accessory palatal
traces; Hivaoa Planudonta matauuna, new species
Planudonta subplanula, new species. Figures
147f-g; 148.
Description. — Shell large, with 6% tightly coiled whorls. Apex
and spire depressed slightly below level of body whorl, last whorl
descending a trifle, H/D ratio 0.346. Apical whorls slightly less than
1'j, sculpture typical on most of surface, slightly worn in spots.
Post nuclear whorls with high, prominent, lamellate, protractively
sinuated radial ribs, 84 on the body whorl, whose interstices are 2-4
times their width. Microsculpture of fine radial riblets. four to six
between each pair of major ribs, with barely visible traces of
microspiral ribbing. Sutures deep, whorls very strongly rounded
above and on moderately shouldered umbilical margin, with evenly
rounded outer margin. Umbilicus broadly V-shaped, regularly
decoiling. contained 1.68 times in the diameter. Walls of umbilicus
slightly flattened internally, ribbing sharply angled and becoming
very slender just before umbilical sutures. Color light yellow horn,
338
SOLEM: ENDODONTOID LAND SNAILS
• DG
CR
PP
DG
PP
FIG. 147. Anatomy of Planudonta: a-b, P. intermedia. Mt. Ooumu, Nukuhiva, Marquesas. BPBM 96057. a, genitalia, b, interior of
penis; c-e, P. concava. Mt. Ooumu, Nukuhiva, Marquesas, c, genitalia, d, interior of penis, e, talon and carrefour; f-g, P. subplanula.
Puokoko. Nukuhiva, Marquesas. BPBM 95936. /, terminal genitalia, g, interior of penis. (See Appendix for explanation of abbreviations.)
with broad, somewhat irregularly spaced, reddish flammulations that
become narrowed and strongly zigzagged near periphery, becoming
broader again on shell base and in umbilicus. Aperture ovate, with
evenly rounded outer margin, inclined about 15° from shell axis.
Parietal barriers 2, extending posteriorly almost one-quarter whorl:
upper a high, thin lamellar ridge, weakly expanded and serrated
above on posterior quarter, with very gradual anterior descension;
2nd parietal distinctly higher posteriorly, expanded and serrated
above on posterior quarter, with rather sharp anterior descension to
threadlike anterior half that terminates slightly beyond end of upper
parietal. Palatal barriers 3, deeply recessed within aperture, low
lamellar ridges: 1st basal in position, a short threadlike trace; 2nd an
elevated, V-shaped ridge, with gradual anterior descension; 3rd
slightly supraperipheral, a low and threadlike trace. Height of
holotype 1.58 mm., diameter 4.57 mm.
Holotype. — Marquesas Islands: Nukuhiva,
Puokoko on Tunoa Ridge at 3,485 ft. elevation.
Collected on ferns or shrubs on November 22, 1929, by
SYSTEMATIC REVIEW
339
members of the Pacific Entomological Survey. BPBM
95936.
Range. — Nukuhiva, Marquesas Islands.
Paratype. - BPBM 98252.
Material. — Nukuhiva: Puokoko on Tunoa Ridge
at 3,485 ft. elevation (1 specimen, BPBM 95936); Tovii
region at 200 ft. elevation (1 specimen, BPBM 98252).
Remarks. — A specimen from the Tovii region of
Nukuhiva (BPBM 98252) is tentatively referred here
despite several differences. It is obviously subadult, has
a greater H/D ratio than the holotype (table XCIV),
much more widely spaced ribbing, lacks the lower
parietal, and has only two small palatals. The whorls
are also more loosely coiled and more strongly rounded
above (table XCV). The similarities are sufficient that
I prefer to consider them conspecific.
The only slightly depressed spire, retention of 3
palatals, and very wide umbilicus separate P. subplan-
ula from the other species of Planudonta.
Unfortunately, the type specimen is not fully
grown. While partial descension of the body whorl has
occurred, there is no indication of change in the
ribbing pattern at the aperture and an estimated
additional quarter whorl of growth could occur before
cessation of growth as a gerontic individual. An adult
size of 5 mm. is quite possible.
Description of soft parts. — Only a fragmentary, very smashed
individual was available. No details of muscular or digestive system
could be determined and only a small part of the terminal genitalia
remained.
Lower part of penis (fig. 147f, P) swollen and twisted, internally
(fig. 147g) with two pilasters, one large and hemispherical, one low
and broad, that continue apically as two low pilasters. Area between
pilasters in swollen area densely papillose. Atrium (Y) long and
slender. Shaft of spermatheca (S) and remnant of free oviduct (UV)
typical.
Jaw of about 20 rather narrow plates on each side, edges free,
middle area partly fused.
Radula with centrals tricuspid, about 6 n wide and 8-10 n long.
More than 100 rows, with about eight laterals and ten marginals.
Latter rectangular, mesocone split with inner cusp distinctly smaller,
ectocone split into two to four cusps of variable length, shorter than
main mesoconal cusp and always narrower, but sometimes as long as
main mesoconal cusp. Laterals without endocone until 6th or 7th,
transition to square marginals occurring in three or four rows.
(Based on BPBM 95936, one fragmentary example.)
Planudonta intermedia, new species. Figures 147
a-b; 149c-d.
Description. - Shell small, with 6'4 tightly coiled whorls. Apex
and early spire distinctly sunken beneath level of penultimate whorl,
last half of body whorl descending rather rapidly below level of
penultimate whorl, H/D ratio 0.413. Embryonic whorls slightly less
than l'/2, sculpture eroded from most of upper surface, with
microradial and microspiral traces visible in sutures, visible in
umbilicus as typical microradial ribbing, with first half whorl
macroscopically smooth. Postnuclear whorls with high, narrow,
slightly protractively sinuated radial ribs, 77 on the body whorl,
whose interstices are 3-5 times their width. Microsculpture of very
fine radial riblets, five to ten between each pair of major ribs, crossed
by exceedingly fine and crowded spiral riblets that are barely visible
under 96 X magnification, with a secondary sculpture of narrow,
rather widely spaced spiral cords. Sutures deep, whorls strongly
shouldered above and on basal margin, markedly compressed
laterally, with evenly rounded outer margin. Color light yellowish-
white, with broad, irregular, strongly zigzagged, reddish
flammulations. Umbilicus broadly open, V-shaped, regularly decoil-
ing, contained 1.93 times in the diameter, with flattened walls on
which the upper third of each volution lacks any formed sculpture.
Aperture compressedly ovate, strongly shouldered above and on
basal margin, inclined less than 10° from shell axis. Parietal barriers
2, extending posteriorly beyond line of vision, with eleven deeply
recessed threadlike traces: upper parietal relatively low, strongly
expanded and serrated above on posterior visible three-quarters, with
rather gradual anterior descension; 2nd parietal slightly reduced in
height, equally expanded and serrated above posteriorly, with more
gradual anterior descension; 2nd parietal slightly reduced in height,
equally expanded and serrated above posteriorly, with more gradual
anterior descension to a threadlike anterior that extends slightly
beyond end of upper parietal. Accessory traces located three above
upper parietal; four between 1st and 2nd parietal; and six below 2nd
parietal. Columellar and palatal walls with numerous, extremely fine
threadlike ridges, that extend posteriorly beyond line of vision: one
columellar and two palatal traces are slightly more elevated than the
remaining, but still are threadlike in character. Height of holotype
1.61 mm., diameter 3.75 mm.
Holotype. — Marquesas Islands: Nukuhiva, near
summit of Mt. Ooumu at 4,050 ft. elevation. Collected
among dead leaves and wet humus on November 12,
1929, by members of the Pacific Entomological Survey.
BPBM 96057.
Range. — Nukuhiva, Marquesas Islands.
Material. — Only the holotype is known.
Remarks. — The apertural barriers recall that of
Taipidon centadentata, except that in Planudonta
intermedia the palatal riblets extend posteriorly
beyond the line of vision while in T. centadentata they
are less than one-sixteenth of a whorl in length. The
upper columellar and two of the mid-palatal traces are
distinctly more elevated than the others. Descension of
the body whorl is substantial and there is partial
gerontic ribbing pattern just behind the aperture. The
specimen probably is fully adult, but gerontic growth
could have continued for a small fraction of a whorl.
Planudonta matauuna agrees in having the ac-
cessory parietal traces, but their number and length
are greatly increased in P. intermedia. Its name is
derived from the growth pattern and umbilical form,
which lie between the patterns of P. subplanula and P.
concava. The penis is unusual only in the very large
size of the pilasters.
Description of soft parts. — External features and partial pallial
complex without unusual structures.
Apical genitalia not available for study.
Prostate (fig. 147a, DG) shorter and with larger acini than in P.
concava. Uterus (UT) bipartite, lower portion extending below vas
deferens origin.
Vas deferens (VD) typical, entering penis laterally between
major pilasters, about 0.43 mm. below penis head. Penial retractor
(PR) arising from columellar muscle, inserting onto fleshy extension
of penis head. Penis (P) about 4.6 mm. long, slightly tapering, with a
short, fleshy extension, internally (fig. 147b) with two nearly circular
pilasters (PP) that unite at penis apex. One fades out into a series of
340
SOLEM: ENDODONTOID LAND SNAILS
ab
cd
FIG. 148. Planudonta subplanula, new species: a-b, Puokoko, 3,485 ft., Nukuhiva, Marquesas. Holotype. BPBM 95936; c-d, Tovii,
Nukuhiva, Marquesas. Paratype. BPBM 98252. Scale lines equal 1 mm. Drawings by YK reproduced through the courtesy of Bernice P.
Bishop Museum.
transverse rugae after upper fifth, other continues to atrium. Atrium
(Y) incomplete in only available example.
Free oviduct (UV) not clearly distinguished externally from
uterus, internally with much finer pustulations. Spermatheca (S)
with head missing, shaft inserting directly into penioviducal angle.
Free muscle system and digestive system incomplete and not
studied.
Jaw and radula not successfully mounted.
(Based on BPBM 96057, one partly extracted specimen.)
Planudonta concava, new species.
149a-b.
Figures 147c-e;
Description. — Shell very large, with 6% tightly coiled whorls.
Apex and spire deeply and evenly sunken beneath level of first half
of body whorl, last half of body whorl descending moderately until
below level of penultimate at aperture. H/D ratio 0.364. Apical
whorls 1%, typical microsculpture visible in sutures, surface worn.
Postnuclear sculpture of high, prominent, lamellar, strongly protrac-
tively sinuated radial ribs, 69 on the body whorl, whose interstices
are 3-5 times their width. Microsculpture of fine radial riblets, six to
ten between each pair of major ribs, crossed by barely visible
microspirals. Sutures deep, whorls strongly rounded above and
shouldered below on basal margin, somewhat compressed laterally,
with evenly rounded outer margin. Color light yellow-white, with
broad, irregularly spaced, reddish flammulations that become
strongly zigzagged near periphery and fade out on shell base.
Umbilicus very broadly open, quite shallow, regularly decoiling,
contained 1.74 times in the diameter, with upper one-quarter to one-
half of each umbilical whorl lacking major sculpture. Aperture ovate,
shouldered above on basal margin, inclined about 20° from shell axis.
Parietal barriers 2, extending posteriorly less than three-sixteenths of
a whorl: upper a moderately elevated, V-shaped ridge, not expanded
above posteriorly, with rather sharp anterior descension; 2nd parietal
a threadlike trace, equal in length to upper parietal, very weakly
expanded above on posterior third. A very thick, slightly elevated
callus near point where columellar wall dips around umbilical margin
gives impression of being an additional parietal. Palatal and
columellar walls without barriers. Height of holotype 2.10 mm.,
diameter 5.79 mm.
Holotype. — Marquesas Islands: Nukuhiva, ridge
of Mt. Ooumu at 3,900 ft. elevation. Collected on the
ground under dead leaves on November 13, 1929 by
members of the Pacific Entomological Survey. BPBM
96102.
SYSTEMATIC REVIEW
341
a
ab
cde
FIG. 149. a-b, Planudonta concava, new species. Mt. Ooumu, 3,900 ft., Nukuhiva, Marquesas. Holotype. BPBM 96102; c-d, Planudonta
intermedia, new species. Mt. Ooumu, 4,050 ft., Nukuhiva, Marquesas. Holotype. BPBM 96057; e, Planudonta matauuna, new species.
Matauuna, 3,800 ft., Hivaoa, Marquesas. Holotype. BPBM 98789. Scale lines equal 1 mm. Drawings by YK reproduced through the courtesy of
Bernice P. Bishop Museum.
Range. — Nukuhiva, Marquesas Islands.
Material. — Only the holotype is known.
Remarks. — The very depressed apex and
complete absence of any palatal or columellar barriers
separate Planudonta concava from the other plan-
orbiform Marquesan endodontids. The comparatively
large size of P. concava may simply be a function of its
being an adult shell while the types of P. subplanula
and P. intermedia may be subadult. The very broad
and shallow umbilicus with even depression of the
apex and spire differ markedly from the almost flat
apex and rather deep umbilicus of P. subplanula. The
latter retains palatal barriers and has a much
narrower zone of riblessness on the umbilical whorls.
The only known specimen of P. concava is
gerontic with typical breakdown in ribbing pattern
just behind the aperture. It is conceivable that existing
palatal barriers were resorbed during this gerontic
growth (see, for example, Minidonta simulata, fig.
70d), but the absence of any parietal reduction and
342
SOLEM: ENDODONTOID LAND SNAILS
any lip callus or irregularities makes me doubt the
possibility of secondary reduction. Descent of the body
whorl has proceeded far enough that the columellar
wall lies inside the umbilical margin of the pen-
ultimate whorl at the aperture. Extensive callus
formation has been required to fill in this angle and
this growth gives the impression of forming a barrier at
the parietal-columellar angle (fig. 149a, b). I am
uncertain as to whether a 3rd parietal exists in young
shells and has been covered by callus formation, or
whether this trace barrier is an artifact of deposition
unique to this specimen.
Description of soft parts. — Only a partial extracted specimen
was available. External features as in all examined Endodontidae.
Mantle collar thick, without separate lobes, a slender glandular
extension onto lung roof. Pneumostome and anus typical.
Pallial region about 6.8 mm. long. Lung roof clear, without
granulations. Kidney about 3.03 mm. long, rectal lobe 1.32 mm. and
appressed to hindgut. Ureter typical, reflexed posteriorly alongside
rectal kidney arm, opening just anterior to rectal kidney arm
termination. Heart about 1.5 mm. long, slightly angled to plane of
hindgut. Principal pulmonary vein large, running to mantle gland
extension.
Ovotestis and hermaphroditic duct not available for study.
Albumen gland (fig. 147c, GG) very slender, only partly shown in
drawing, much longer than talon. Talon (fig. 147e, GT) with short
thick shaft, not tapering, entering top of slightly more swollen
carrefour. Prostate (DG) flattened, two or three rows of acini
attached to a narrow tube. Uterus (UT) typically bipartite, lower
chamber extending well below level of vas deferens origin.
Vas deferens (VD) loosely bound to penioviducal angle, entering
penis laterally between major pilasters, about 0.72 mm. below head.
Penial retractor (PR) apparently arising from columellar muscle,
inserting directly onto fleshy extension of penis head. Penis (P)
about 6.05 mm. long, very slender and tapering gradually, with a
firm, slender, fleshy extension well above entrance of vas deferens.
Internally (fig. 147d, PP) with two very slender, elevated pilasters
above, which merge into a papillose central portion, but reappear as
formed, semicircular pilasters just before atrium. Atrium (Y) very
long and slender.
Free oviduct (UV) internally much more finely papillose than
uterine section, externally not clearly differentiated. Spermatheca
(S) with oblong head lying next to albumen gland, slender shaft
inserting into penioviducal angle. Vagina absent.
Free muscle system not studied.
Jaw about 60ft wide, composed of separated plates that are one-
third as wide as long in small fragment mounted. Central area not
differentiated.
Radula with centrals about lOfi long and Sfi wide, 10-11 laterals
and more than 7 marginals. Tooth structure as in Planudonta
subplanula.
(Based on BPBM 96102, one partial specimen.)
Planudonta matauuna, new species. Figure 149e.
Description. — Shell small, with 5'4 tightly coiled whorls. Apex
and spire moderately and evenly depressed below level of pen-
ultimate whorl, last half of body whorl descending moderately
rapidly to point below level of penultimate whorl at aperture, H/D
ratio 0.449. Apical whorls 1'i. traces of typical sculpture visible in
sutures of umbilicus, eroded from apex of shell. Postnuclear
sculpture of high, prominent, rather widely spaced, slightly protrac-
tively sinuated radial ribs, 44 on the body whorl, whose interstices
are 4-6 times their width. Microsculpture of fine radial riblets, nine
to twelve between each pair of major ribs, crossed by barely visible
spiral riblets. Sutures deep, whorls strongly rounded above and on
shouldered umbilical margin, compressed laterally, with evenly
rounded outer margin. Color light yellow-white, with narrow,
irregular, reddish flammulations that become strongly zigzagged on
side of shell base. Umbilicus broadly open, cup-shaped, regularly
decoiling, contained 2.07 times in the diameter, upper third of each
whorl without typical ribbing. Aperture subovate, strongly
compressed laterally, shouldered above and on umbilical margin,
inclined about 10° from shell axis. Parietal wall with 2 major
barriers, extending posteriorly somewhat more than one-eighth
whorl, with four accessory traces: upper parietal a moderately
elevated lamellar ridge, weakly expanded above on posterior half,
with rather gradual anterior descension; 2nd parietal a low elevated
threadlike ridge, not obviously expanded or elevated posteriorly.
Accessory traces located near parietal-palatal margin, between 1st
and 2nd parietal, with two below 2nd parietal, all short, deeply
recessed and threadlike. Columellar wall with two short, in-
conspicuous threadlike traces that reach only to top of columellar
callus. Remnant of palatal wall with three subperipheral, widely
spaced, threadlike traces. Height of holotype 1.74 mm., diameter 3.88
Holotype. — Marquesas Islands: Hivaoa, Ma-
tauuna, north of Mt. Temetiu's summit at 3,800 ft.
elevation. Collected among dead leaves on March 3,
1930 by members of the Pacific Entomological Survey.
BPBM 98789.
Range. — Hivaoa, Marquesas Islands.
Material. — Only the holotype is known.
Remarks. — The holotype of Planudonta ma-
tauuna is a dead specimen with the umbilical region
and part of the body whorl badly broken. The very
widely spaced ribbing (ribs/mm. 3.61) and what seems
to be a quite distinct pattern of apertural barriers
required description of this specimen as a species. The
palatal traces (not shown in the type figure) are much
shorter and differently placed than the enlarged traces
seen in P. intermedia (fig. 149c), although the larger
parietals of both species are almost identical.
Compared with the other Planudonta, P. matauuna
has a much deeper, cup-shaped umbilicus and very
widely spaced radial ribbing. P. concava, the only
species with similarly spaced ribbing, is much, much
larger and has a very shallow, V-shaped umbilicus.
Although the type has a subadult lip growth, actual
adult size probably differs only slightly, since consid-
erable descension of the body whorl has occurred and,
judging from the other Planudonta, probably less than
one-eighth whorl of growth would be terminal.
Genus Rikitea, new genus (Solem & Cooke)
Rather small, widely umbilicated Endodontidae in which the
apertural barriers are reduced to 1 extremely large parietal.
Columellar and palatal barriers absent. Ribbing prominent, micro-
sculpture unknown. Elevation of apex and whorl count unknown,
body whorl descending rapidly. Sutures deep, whorls evenly rounded.
Type species. — Rikitea insolens, new species.
At first glance, Rikitea insolens would seem to be
a relative of Nesodiscus obolus, distinguished primarily
by the heavy ribbing and enlarged parietal.
Comparison of whorl contours, ribbing type, size
2
C0|
V1
o
U
CM!
to
D
o
CO
H
Q
O
CQ
EH
H
K
3
PM
H
§
M
EH
M
I
O
g
O
X
w
I
5
n)
co ^j, oo TJ,
CO CO CD IO
||1
111
z <5r «
(U
2
S.
o*
(-^ TJ* O>
o o o
10
•
CO
o
CM*
fll
2
n)
.3
e
Planudonta
subplanu]
intermed
concava
matauuai
Rikitea
insole ns
co
10
oo
•
•*
si
SS
w O
2m
0
IO
10
oo'
S
CM
•
IO
a,
§
CM
CD
I
>
o
s
C5
J
i
§
co
CM
co~
CD
65"
o
§
c-
c-
o
<N
1
CM"
i
CM'
CM'
1
CO
CO
•
O
o
•
IO
O5
cS
c-
Jy-
^^
£
i— H
•
f-H
O
3
0
05
O5
O5
CM*
•
CM
CM*
i— 1
-*
1-1
co"
00
0?
—
^
co
10
\
i
CO
J
oo
c-
>
co
•>
rt
1
^
IO
CD
CO
C^1
CD
^^
4<
OO
CM
oo
CO
00
••i
IT-
^)
t~
*^s
-f
f^
CO
CO
CD
c-
c-
r-
CO
C-
•*
CO
CM
co
10
o
CD
10
IO
•
o
•
0
O
1
o
1
O
o
i
O5
CD
IO
c-
•*
oo
CO
co
co
•<#
co
CO
^f
'I1
•
o
•
O
o
o
O
N-^
O
o
u^
MI
t—l
c-
N
O5
o
•*
IO
CO
•*
•*
IO
0
o
o
O
O
o
C?
00
?
CO
10
53
•
•
CO
c-
co
CD
to
1
1
i
1
s
3
CO
o
CM
CD
cS
(M
OO
•
•
•
10
iS
CD'
LO
55-
I— I
o"
IO
CD
5
CD
CD'
o
•
10
•
IO
IO
CO
e-
CO*
§
•
CM
1
C-
co
CM
CM
G>
CM
•
<N
o
•
1
s
P
CD
03
OO
o
co
10
10
c-
CM'
9
•
•
CM
CM*
JJ
i>
o'
T— (
£:
CO*
CO
IO
o
•
CM
d
•
•
<N
•
co
co
O
o
CM
o
0
<N
Q
^H tlj
Q
Q
>-
>
2 »— ^
> 5
DP ID
^ Q
§B
> Q
O
O
S
s
a
a
c-
00
3
343
344
SOLEM: ENDODONTOID LAND SNAILS
(table XCV), parietal barrier structure, and pattern of
whorl coiling leaves no choice but to consider them
unrelated. In Nesodiscus obolus the whorls are
distinctly flattened and the periphery angulated, the
sutures much shallower; the ribbing reduced to
strongly protractively sinuated microradials; the adult
size is about 4.75 mm.; the parietal barrier an elevated
threadlike ridge that is distinctly supraperipheral; and
the whorls are very tightly coiled. Rikitea insolens has
the whorls evenly rounded and the sutures deep; the
ribbing is very prominent and only slightly protrac-
tively sinuated; the adult size is less than 3 mm.; the
parietal barrier a greatly elevated lamellar blade that
is medial; and the whorls, by extrapolation from the
remaining part, much more loosely coiled.
Considerable reluctance was felt in describing a
genus from a single partial individual, but the
differences are so striking that nomenclatural recogni-
tion has been given. The single huge parietal barrier
finds its parallel only in Discocharopa (see Part II).
In the absence of the apical whorls and with the worn
condition preventing study of the microsculpture,
determining the exact relationship that Rikitea bears
to other genera is not possible. The general form of the
sculpture agrees with Taipidon, but the pattern of
coiling almost certainly is different. Anceyodonta,
Minidonta, and Gambiodonta differ in nearly every
character of shape and umbilicus, but the form of the
parietal barrier and the ribbing could, without
difficulty, be derived from the Minidonta -Anceyodonta
type. The complete absence of accessory traces,
columellar and palatal barriers in Rikitea is not
significant, since the loss of these has occurred several
times in different lineages. Probably Rikitea is a quite
isolated derivative from Minidonta, but more complete
material will be needed to determine its affinities.
Rikitea insolens, new species (Cooke & Solem).
Figure 150.
Description. — Shell smaller than average, apex and early
whorls missing so that whorl count is unknown. Descension of last
whorl accelerating rapidly, spire probably flat or only slightly
elevated, H/D ratio probably about 0.421. Microsculpture worn off
entire surface, apical sculpture unknown. Body whorl with 48 very
prominent, high, slightly protractively sinuated radial ribs whose
interstices are about twice their width (too widely spaced in fig.
150a). Sutures deep, whorls strongly rounded above, with evenly
rounded outer margin and slight shouldering of umbilical margin.
Aperture nearly circular, inclined about 15° from shell axis. Parietal
wall with single, very high, medially placed barrier, extending
posteriorly beyond line of vision, with gradual anterior descension on
visible anterior quarter until just before termination, when descen-
sion becomes abrupt. Barrier worn on surface, but remnants of
strong superior expansion and probable serration remain. Height of
specimen with apex and most of spire missing 1.22 mm., diameter
2.90 mm.
Holotype. — Gambier Islands: Mangareva, Station
187, Mangareva Islet, north part of Rikitea. Collected
by Yoshio Kondo on June 27, 1934. BPBM 141663.
Range. — Mangareva Islet, Mangareva, Gambier
Islands.
Material. — Only the holotype is known.
Remarks. — Associated with the single example of
Rikitea insolens were one specimen each of Minidonta
simulata, Anceyodonta subconica, A. ganhutuensis,
and Gambiodonta mangarevana; two specimens of
Anceyodonta andersoni; six each of A. difficilis and
A. hamyana; nine of A. obesa; and 15 of A.
sexlamellata. Comparatively little material was
obtained from this station and further collecting
probably would yield additional specimens of Rikitea.
Differences from Nesodiscus obolus have been
given above under the discussion of the generic
affinities. The only other species that might be
confused are some of the Hawaiian taxa with reduced
apertural barriers, such as Cookeconcha decussatulus,
C. lanaiensis, and C. jugosus. All are much larger,
with narrower umbilici, different whorl contours, and
marked secondary spiral cording.
I-
-\
FIG. 150. a-b, Rikitea insolens, new species. Station 187,
Mangareva Islet, Mangareva, Gambier Islands. Holotype. BPBM
141663. a, side; 6, base of shell. Scale line equals 1 mm. Drawings by
YK reproduced through the courtesy of Bernice P. Bishop Museum.
SYSTEMATIC REVIEW
345
Rikitea insolens is quite unlike any species of
similar size and the name insolens refers to its unusual
structure. Although much smaller in size, I suspect
that Rikitea represents the Mangarevan equivalent of
the Nesodiscus level of organization.
Genus Nesodiscus Thiele, 1931
Hand. Syst. Weichtierkunde, 1, (2), p. 571.
Endodontidae with the major apical sculpture consisting of large
and broadly rounded radial ribs, apical microsculpture typical.
Postnuclear whorls with very fine and crowded ribs in most species,
larger ribs present in magnificus, restricted to upper spire in taneae.
All sculpture greatly reduced in cretaceus and fabrefactus. Apex
often markedly protruding, except in fabrefactus and magnificus,
spire rarely flat (form obolus), usually moderately elevated and
convex, strongly elevated in form celsus and strongly elevated with
concave sides in fabrefactus. Mean H/D ratio much less than 0.500
in all but celsus and fabrefactus. Body whorl with angled to strongly
keeled periphery, rarely rounded in obolus. Whorls 6-8, lower counts
in the smaller species. Umbilicus very broadly open, U-shaped
in magnificus, cup-shaped in most species, mean D/U ratio 1.90-2.15
except narrower in huaheinensis, taneae and magnificus. Size large
to very large. Parietal wall generally with 1 low barrier extending
posteriorly beyond line of vision, absent in typical fabrefactus, a 2nd
deeply recessed parietal in taneae and huaheinensis, rarely in obolus.
Columellar wall without barriers. Palatal barriers very deeply
recessed, variable in number: normally 4 in taneae and huaheinensis;
1 in cretaceus and fictus; 0-3 in obolus', absent in fabrefactus and
magnificus. Soft parts not examined except in fictus and penial
complex of fabrefactus. Pallial organs and apical viscera typical of
family, except for effects of narrowing whorl diameter and
lengthening of organs. Penial retractor originating partly from
diaphragm, partly from columellar muscle, inserting directly on penis
head. Vas deferens entering penis laterally between united pilasters.
Penis short, expanded supramedially or slender, depending on degree
of pilaster expansion and folding, internally with two equal pilasters
united above at penis head. Prostate shorter than free oviduct,
vagina not differentiated. Radula and jaw typical.
Type species. — Helix fabrefactus Pease, 1864, by
monotypy.
Originally it was proposed as monotypic for the
only known species of the Endodontidae that totally
lacks apertural barriers. The only extended use of the
generic name has been the reference of Endodonta
acuticarinata Thiele, 1928, to Nesodiscus by Use
Rensch (1937, p. 586, fig. 8). This species is a
paryphantid (Solem, 1959b, pp. 155-156) and totally
unrelated to the Society Island genus.
Nesodiscus undoubtedly is a derivative from the
same stock that produced Mautodontha boraborensis.
The structural trends which differentiate that species
from the generalized Mautodontha — increased size
and whorl count, deeper recession of the palatal
barriers and increased length of the parietals, reduced
sculpture, wider umbilicus, and depressed form — all
are greatly intensified in Nesodiscus. There is a large
and distinct gap between Nesodiscus and Mau-
todontha boraborensis. The latter retains 4 parietals,
the apical sculpture is fine and not coarsened, the
ribbing less crowded and more distinct, the periphery
is obtusely angled, and the palatal barriers remain
quite short. In the most generalized Nesodiscus, the
apex is protruded and with coarse radial ribs (fig. 31b),
there are only 2 parietals (with the lower very deeply
recessed), the radial ribbing is reduced (taneae) or
extremely fine and crowded (obolus), the periphery is
sharply angulated or keeled, and the much more
deeply recessed palatals are very short. While Mau-
todontha boraborensis reaches the size, whorl count,
and apparently has the same umbilical mucus closure
(see p. 156) found in the Borabora Island Nesodiscus,
the great majority of its features agree more with
Mautodontha. It has been classified in that genus.
Minidonta and Anceyodonta from Mangareva are the
only other situation in which there are species so
nearly transitional between genera in the Endodon-
tidae.
:
FlG. 151. Umbilical mucus cover in Nesodiscus taneae.
Borabora, Society Islands. FMNH 116516. Left, closed; right, opened
with eggs removed. (MM).
Within Nesodiscus, increased size correlates with
loss of the lower parietal and most to all of the
palatals, continued sculptural reduction (except mag-
nificus), flattening of the whorls and increased
peripheral and umbilical keeling. In the Boraboran
species, N. taneae, N. cretaceus, and N. magnificus,
the eggs are brooded in the umbilicus and sealed in by
a mucus membrane (fig. 151). Garrett (1884, p. 42)
reported that this membrane was frequent in the
Borabora specimens of N. taneae, but had not been
observed in Maupiti specimens. None of the Huahine,
Tahaa, or Raiatean specimens examined during this
study showed unmistakable traces of the mucus seal.
This may be restricted to Boraboran species.
Except for the large populations of Nesodiscus
fictus collected during the Mangarevan Expedition, all
available material of Nesodiscus consisted of small sets
in museums that dated from Garrett and Pease, large
sets of incredibly mixed species and genera in the
Pease collection at the Museum of Comparative
Zoology, plus a few dead shells taken by the
Mangarevan Expedition. Garrett collected these spe-
cies by the hundreds. Available specimens represent a
small fraction of those collected by Garrett. They had
been sorted to varietal name, exchanged one or more
times, and hence would be biased strongly for extremes
in size and shape. The variation recorded for individual
sets (table XCVI) has no necessary relevance to the
actual population parameters. The extent and types of
bias in the sets of N. fictus from Stations 1081 and
1085, as sorted by the Bishop Museum staff in the
mid-1930's, is outlined below. I presume that the bias
03
^3
O
CO
H
P
O
CQ
H
O
H
EH
>
I-H
O
o
l-H
5
X
c—
00
CO
CM
00
CD
1
(N*
C- 1 CO
CO (N -^
O CO O
CM"
CO
•*
O
00
co
CO
CO
o
CM*
OS
CO
rH
CM*
I
p
O* CM* O*
CM
o
CM
o*
<M
O
rt
D
-H +f
m co
-H
C-
-H
CO
-H
CO
CD in
•^
1^-
CM* CM*
CM
CM*
CM
0?
^
00
^
0?
43
"*°^^
+ co
co
i-H
1
t—t
CM
'^'^
*^L CO
CO
00
^AJ
CO
""^^
m
TY? l i
i
CO
^^
1
t~H
i
|™
•"••p CD
^
00
CM
IO
•^
^>
tO -s*.
•^s
^x*
1C
^^
^^
CO
CO
CO
rH
rH
s
e
e
in
S-
co
f~*.
CD
in
^,
f— X
t-H
CM
m
t
CO
m
^
CO
in
•2
m
o
CM ' ^f
Tjl O <^>
o
c-
CM
00
s
o
O5
CO
1
o
CO
00
,_!
0
CO
CO
e£
o ^ o
CO
0
co
o
CO
o
•*
Q
o ° o
O
o
o
o
o
o
0
X
-H % -H
in co
CO O
CM
CO
O
•^ ^
•^
•^
in
o o*
O
0
o
CD
CO
^ ^
,-,
00
CD
m
^
OS
CO
8
0
E
in
o ' co
TJ< ^ in
rH °° 0
in*
CO
(N
in
rH
in
CO
CO
rH
•^
1
CO
I
o
•*'
CO
I-H
.2
o ^ o
•*
o
•*
O
•*
o
•cf
Q
CO C-
-H
in
-H
co
c-
CO rH
OO
CD
CM
in* in*
•*'
*
**
^,
^^
CM
-
c?
/-^
O5
O5
OS
CM
CM
CM*
(M*
CM*
(N*
CM*
«
rH ' CM
1
<N
1
O5
i
o
1
§
rH r* O
OO
CO
I-l
0
t-
00
O
o
c-
o
§
X
O w O
rH
o
rH
O
rH
o
H
-H -H
-H
-H
-H
CO
O5
CM
e-
^ rH
O
cn
rH
CM* (N*
CM*
rH
CM*
o c
1 1
C— ^1
j— |
C-
CD
m
11
•-
1
05
00
C-"
1
CO CD
CO
00 CD CO
O
CO CO O
CM
OO
CM CM 00
OS
c-
c-
m in r-
c-
CD
rH
2 fH
co
rH
CO
2
2
^
<l)
E 8
•° oa oa ~r
o oa m <
03
O,
oa
§
CO
CQ
<* S
oa
2 3
CM
CO
in
o
•H
O
00
CD
+ I
CO OO
c-
m
00 00
rH 00
o <*\
o g,
-H
O
CO
CO
oo
0
o
o
o
o*
in
o
OS
in
co
co
co
CD
CD
in ^x
m
<=>
0
IT-
CO
O*
o
in*
co
c-
a
CM
05 '
m 2
-H
CO
CO
CM
CD
I I
CD CO
^v
in
m
CM
CO
CM
CN
in
CM
OJ ^
.52
.c oa
n) d.
a oa
m
co
co
o
-H
CM
OS
O>
CO
o
-H
e-
CO
CD
o* s
4H
in
CM
CO*
CO
us
^
c-
CO
2
<o
C E
S m
oa
a.
CO
•*
CO
0
tu
"2
E °9
Sm
tb
OS
o
o <*'
Is
05
O
-
-v,
CO
CD
-^
CO
, — *
c-
co
IP
CT>
N
CO
CO
<*
o*
o
o"
0*
t-
00
co1
OO
o
c-
CO
CO
05
i
o
1
c~*
rH
co
o
rH
OO
0
°^
O
CO
o
^.
O
CO
•
o
o"
O
o
o
o
O*
0
+1
•H
-H
-H
c-
CO
T-H
OS
0
O
CO
O
CO
T^
^
^
88
9
CO
00
00
05
m
in
c-
CM"
rH*
<N*
CO*
CM"
Is
CO ^
O5 '
§s
CM <N
Is
o" i-1'
O rH'
o* rl
o* si
o* ^
-H
-H
-H V
s
9
0
rH
rH
IT-
CM
m
csf
rH
CM*
CM*
CM*
o
co
oa
a.
-
u
>-l
o
346
CM
CD
00
1
IO
10
IO
o
o
IO I
••* 10
rH CO
O CO
O O
CO
CO
IO
co i
00 rH
CO O
IO
03
CO I
O CD
IO
00
CM
35
CM
O3
CM
10
O
10 I
O3 O3
CM CD
O CO
O O
CO
c-
CD I
rH t-
rH CD
O CD'
-H '
03
CO
s
03
o
CO
10
c-
co
10
CD C-
O CO
O CO
O O
CM^
CO
c-
CO rH
o o
CO
co
co
C-
co
co'
(N i
^1 CD
O rH
C3 CO*
-H ^— '
CO
CO
co"
co
10
I
•*"
00
CO
CM
1O
10
CO
o
s
oo
^
10
c-
CM
IO
o
O I
C- IO
o oo
O CO
o o
CO
co
CO
c-
O3
c-
O3
co
o
CO
O3
CO
03
C-
rH
03"
C0°
i-H
rH
CM*
rH
rH I
co i co
1
O3
1
co
CO ^
CM IO CO
O
~-f
CO
rH
^
O CO
O CO O
c-
O
CO
O
C-
O rH
O rH O
rH
o
rH
O
rH
-H ' —
-H — ' 4H
-H
-H
83
rH
O O3
03 CO
• •
rH rH
O3
O3
rH
8
rH
0?
C?
0?
C-
CO
1
^s.
rH
So
\
•* 10
00 CO ,-_
c-
^P
C-
CO
1
CO
rH °°
10 rH
co
rH
co
CO
c-
CO CO
CD CD
**^
rH
C^
"**.
c-
C-
CD
CO
CD
^
t~*.
IO
in
^^
0?
O
O3
^
0
IO
•*
IO
IO
CD
o
o"
o
CD
0
IO 1
O 1 IT-
1
CO
1
O3
1
^i* CD
CO CO O
c-
O3
rH
T-H ^
rH rH rH
co
rH
CD
CM
c-
O CO
O
O
^f
o" o
O O O
o
O
Q
O
o
-H *— '
-H
10
IO CO
^
CO
3 ^
rH
CM
^
TT T^
IO
IO
0*
0 0
O
o
c?
^~*
IO
rT
O
^x
0
CO
CM
O3
rH
10
c-
C-'
C-
co'
oo'
1-H 1
CO +1 O
I
O
I
CD
1
IO O
Tj* CO O
O
CO
CM
rH
O CO
O O rH
CO
rH
rH
rH
C-
O CD
O C- O
CD
O
C-
O
c~
-H — ' -H
HH
-H
CM
CO 00
10
0
rH CM
^
• •
c- c-
c-
O3~
oT
C?
^^
^^
IO
10
O3
•*
CD
co"
co'
co"
•*'
^t1'
(N i CO
i
CO
I
O5
1
O CM
rH O3 O
s
CO
rH
O
CO
rH
CD
CO
o CM"
0 CO 0
CO
O
co
O
CO
-H ^^
-H — ' -H
-H
-H
IO
O3 O
co
CO
o
rH 10
co
rH
•
co
co' co'
CO
Tf'
rH
•* CO
10
10
rH
rH
H
0
O3
c- 52
C- 10
I S
03
03
O
O3
c^ *"
IO
CM
CO °
CO
CM
•-"-1 3
i-H
rH
1^1 • *^
oa " J2
z i
CQ
2
CQ
CL CO ^
Q-
0.
CO t«
P ca
CQ
CQ
co
10
10
IO
03
O
CO
IO
CO
CD'
CO I
CD CO
O CO
o 10
•H •— '
CO
o
co'
s
co'
C- "
CO rH
O O
O CO
IO
T3
I
•u
a
Ji
0)
03
CQ
0.
CQ
347
348
SOLEM: ENDODONTOID LAND SNAILS
FIG. 152. Shape variation in Nesodiscus taneae. Material from the W.H. Pease collection, BPBM 170951. (MM).
present in the labelled sets of obolus, acetabulum, and
celsus are at least as large and roughly equivalent.
Since I had comparatively little new material and
only a fraction of the specimens studied by Garrett, I
have deferred to Garrett's judgment in recognizing
specific limits. In certain cases — taneae and huahei-
nensis; cretaceus and fictus; fabrefactus and piceus;
and the forms of obolus — reliance on the mixed
material in the Pease collection would have led to
erroneous conclusions.
Variation within the species is quite large (fig. 152)
and the difficulties of seeing and counting apertural
barriers make use of the key and identification of
juveniles or oddly shaped specimens difficult. To some
extent, the species are separable through use of
measurements taken at three whorls, four whorls, and
five whorls (table XCVII). The distance was measured
from the suture line opposite the first apical whorl
ending to the suture marking the end of the particular
whorl (fig. 153) with the whorls lying parallel to the
ocular micrometer. This character obviously separates
such confusing forms as N. fictus and N. cretaceus,
and can resolve the possibly puzzling individuals of the
piceus-fictus pair. On the average, N. obolus is smaller
SYSTEMATIC REVIEW
349
TABLE XCVII. - EARLY WHORL SIZE IN NESODISCUS
Diameter At
Number of
Specimens
taneae
BPBM 3359
BPBM 152388
huaheinensis
BPBM 2232
obolus form obolus
BPBM 3786
form acetabulum
BPBM 3446
form celsus
BPBM 3484
ere la ecus
ANSP 47832
BPBM 2230
fictus
BPBM 4956
fabrefactus
form pice us
BPBM 4994
magnificus
HOLOTYPE
1.09*0.018
(1.06-1.16)
1.16±0.026
(1.06-1.23)
1.2310.066
(1.16-1.29)
1.23,0.051
(1.06-1.39)
1.02±0.038
(0.93-1.19)
1.03*0.017
(0.96-1.06)
1.06*0.012
(1.03-1.09)
1.13i0.027
(1.09-1.18)
0.94J0.013
(0.89-0.96)
1.33i0.021
(1.23-1.39)
1.11*0.025
(1.03-1.16)
1.74
4W
1.58*0.020
(1.52-1.66)
1.68*0.048
(1.49-1.82)
1.67(0.083
(1.59-1.76)
1.76*0.071
(1.59-1.95)
5W
2. 17i0.041
(2.09-2.35)
2.32i0.069
(2.05-2.52)
2.28i0.099
(2.19-2.38)
2.41i0.097
(2.12-2.72)
1.49 10.036 2.13,0.056
(1.42-1.66) (2.02-2.38)
1.4Si0.026 1.96*0.055
(1.36-1.52) (1.79-2.12)
1.46i0.020 2.03*0.029
(1.39-1.52) (1.92-2.09)
1.55*0.027 2.10i0.030
(1.51-1.60) (2.04-2.14)
1.30*0.016 1.73*0.019
(1.26-1.32) (1.69-1.79)
1.76*0.038 2.35,0.072
(1.59-1.85) (2.05i2.55)
1.44*0.032 1.87*0.044
(1.32-1.52) (1.72-1.99)
than N. taneae or N. huaheinensis in respect to the
early whorl size, but there is some overlap. More than
in any other genus of the Endodontidae, certain
identification requires the availability of series.
Anatomical data were available for only two of the
most specialized species, N. fictus and N. fabre-
factus. Binney (1885, p. 89, pi. 2, fig. L; reprinted by
Pilsbry, 1893-1895, p. 25, pi. 9, fig. 22) figured a few
radular teeth of Nesodiscus huaheinensis, but these
showed no unusual features. There were six laterals
and 12 marginals. Only fragmentary material of N.
fabrefactus was seen, but there was excellent material
of N. fictus. That species has a mean whorl count
7%+) exceeded only by Kleokyphus hypsus (8) and
Libera incognata (8+). Two other species, Libera
jacquinoti and L. streptaxon have about 7% whorls,
and the Fijian Priceconcha tuvuthaensis has about 7%
whorls. All other species are significantly lower in
whorl count. The great whorl count increase combines
with the very widely open umbilicus to greatly reduce
individual whorl cross-sectional area when compared
to a species of similar size with fewer whorls and a
narrower umbilicus. Hence, there is less space available
and many organs are both narrowed and elongated.
The prostatic acini, for example, normally are three or
four times as long as they are wide; in N. fictus they
are almost square. The pericardial arm of the kidney
(fig. 154b) is greatly narrowed compared with the
ureter. The albumen gland is proportionately very
FIG. 153. Method of early whorl measurement in Nesodiscus.
long and several times the length of the talon-
carrefour, and the buccal mass is more cyclindrical
than usual with more posterior buccal retractor
insertions.
These are just a few of the elongations and
changes, specializations resulting from whorl in-
crement. Differences found in the Nesodiscus with
lower whorl counts, such as N. taneae, should be
viewed with the realization that most obvious changes
in N. fictus are the result of adaptation to whorl
volume factors.
Systematically important features indicate no
particular specialization. There are two essentially
equal-size penial pilasters, the penial retractor inserts
directly on the penis head, the short vaginal area is
not structurally differentiated, and the vas deferens
enters the penis laterally. Despite the volume changes,
the ovotestis orientation is typical. Thus Nesodiscus is
at the same level of anatomical complexity as
Mautodontha, Minidonta, and Endodonta. Apparent-
ly, there is character displacement between N. fictus
and N. fabrefactus, since they differ markedly in
penial length and the extent of pilaster swelling in the
penial mid-region. This was observed in specimens
collected at the same station.
Within Nesodiscus there is a relatively clear
pattern of increasing specialization and obvious
complementarity of species. N. taneae and N. huahei-
nensis are nearest to Mautodontha, retaining 4
palatals and a relatively narrow umbilicus. IV. taneae
has more rounded whorls and retains traces of major
radial ribbing, thus being a little less specialized than
N. huaheinensis. The two are very similar and
obviously closely related. N. obolus shows more
specialization, with very fine and crowded sculpture,
widening of the umbilicus, loss of the lower parietal
and all palatals, plus increased peripheral angulation,
but still retaining slightly rounded whorls. In their
increasing umbilical angulation, reduction of sculptur-
al prominence, flattening of the whorls, and protrusion
of the peripheral keel, both N. cretaceus and N. fictus
show specializations over the first three species, but
their retention of a single rather large and only
moderately recessed palatal barrier is unexpected since
HV
MG
PR
PR
VD
VD
FIG. 154. Anatomy of
Nesodiscus fictus. Station
1081 (BPBM 139790) and
Station 1085 (BPBM
152284, Tahaa, Society
Islands, a, anterior end of
pallia! cavity; b, posterior
end of pallial cavity; c,
genitalia; d, slightly sub-
adult penis; e, exterior
and interior of fully adult
penis.
350
SYSTEMATIC REVIEW
351
the more generalized species cited above have the
palatals deeply recessed and reduced in size. The
differences between cretaceus and fictus are more in
degree than in kind (see the "Diagnosis" for each
species), except for apex size, and they seem to
represent a second complementary pair. N. fabrefactus,
with its change in whorl and spire contour, greater
sculptural reduction, prominent umbilical keel,
complete loss of apertural barriers (except in form
piceus), and great size is the most specialized species.
Derivation from the same ancestral stock that
produced N. fictus is extremely likely.
A somewhat linear progression is evident, with
obolus forming a lateral branch from a taneae-
huaheinensis type ancestor; cretaceus and fictus
evolving in a different branch from the same stock and
reaching a more complex level of organization; while
fabrefactus evolved from close to the fictus-cretaceus
level of separation. Nesodiscus magnificus would seem
to be a separate line of specialization, since it retains a
rounded umbilical margin, major radial sculpture
(probably), a narrower umbilicus, and changes in
whorl contour that are attributable to the extreme
peripheral keel protrusion rather than to compression
and flattening. Reduction of the apertural barriers to a
single parietal in N. magnificus could be merely a
parallel development and does not suggest any direct
affinity to the cretaceus-fictus-fabrefactus series.
The above information and suggested pattern of
derivation corresponds well with distributional data. If
Tahaa-Raiatea is viewed as the center of origin for
Nesodiscus, then the presence of the most generalized
species, taneae and huaheinensis, on the "periphery"
of Huahine to the east, Borabora and Maupiti north
and west is a typical dispersal pattern. The relative
proximity of Tahaa and Borabora, which lie nearer the
distributional center, ties in with the very similar N.
cretaceus and N. fictus found on these islands. The
most specialized species, N. fabrefactus, lives on both
Raiatea and Tahaa.
More than is usual for the Endodontidae, species
of Nesodiscus inhabit two islands. N. taneae is found
on both Borabora and Maupiti; N. obolus on Raiatea
and Huahine; N. fabrefactus on Raiatea and Tahaa.
N, fictus and N. cretaceus are distinct, but dissection
of the latter might demonstrate a very close relation-
ship. Only N. huaheinensis and N. magnificus are
unquestionably limited to a single island.
The exclusive nature of the Nesodiscus and
Libera distributions may be more than coincidence.
Both have evolved efficient ways of brooding eggs,
Libera by a secondarily narrowed brood chamber and
Nesodiscus by use of a mucus seal over a widely open
umbilicus (at least in the Borabora species). Whether
an accident of dispersal or competitive factors have
kept them isolated is unknown.
KEY TO THE GENUS Nesodiscus
1. Aperture with at least one barrier 2
No apertural barriers Nesodiscus fabrefactus (Pease, 1864)
2. Adult or 7 whorl diameter less than 8 mm 3
Adult or 7 whorl diameter more than 10 mm.
Nesodiscus magnificus, new species
3. Aperture with 2 parietals, lower deeply recessed; 3 or more
palatals 4
Aperture with 1 parietal; only rarely more than 1 palatal 5
4. Wide radial ribs visible on upper spire (fig. 155d); Maupiti or
Borabora Nesodiscus taneae (Garrett, 1872)
No major radial ribs (fig. 155a); Huahine.
Nesodiscus huaheinensis (Pfeiffer, 1853)
5. Single palatal only moderately recessed (fig. 159e); shell surface
macroscopically smooth 6
Usually no palatals, if present, very deeply recessed; shell
surface with crowded, fine ribs.
Nesodiscus obolus (Gould, 1846)
6. Sides of spire convex 7
Sides of spire concave.
Nesodiscus fabrefactus. form piceus (Garrett, 1884)
7. Mean diameter about 5.6 mm.; mean whorl count about 6'/2;
Borabora Nesodiscus cretaceus (Garrett, 1884)
Mean diameter about 6.5 mm.; mean whorl count about 7%;
Tahaa Nesodiscus fictus (Pease, 1864)
Nesodiscus taneae (Garrett, 1872). Figures 151;
152; 155d-f.
Pitys taneae Garrett, 1872, Proc. Calif. Acad. Sci., 4, p. 204 -
Maupiti, Society Islands, found on the ground in damp forests;
Garrett, 1873, Proc. Acad. Nat. Sci., Philadelphia, 1873, p. 234,
pi. 3. fig. 65.
Patula janeae Schmeltz, 1874, Cat. Mus. Godeffroy, 5, p. 93 -
typographical error for taneae Garrett; Pfeiffer, 1876, Monog.
helic. viv., 7, p. 481.
Helix taneae (Garrett), Pfeiffer, 1876, Monog. helic. viv., 7, p. 482.
Endodonta taneae (Garrett), 1884. Jour. Acad. Nat. Sci., Phila-
delphia, 9, ( 1 ), p. 42 — Borabora and Maupiti, Society Islands.
Helix boraborenxis "Pease", Garrett, 1884, foe. cit., p. 42 — a nude
name in the synonymy of taneae Garrett.
Helix (Endodonta) taneae (Garrett), Tryon, 1887, Man. Conchol.,
(2), 3, p. 62, pi. 11, figs. 95-97.
Endodonta garrettii Ancey, 1889, Le Naturaliste, (2), 11, (53), p.
118 - Borabora (?), Society Islands; Pilsbry, 1892, Man.
Conchol., (2), 8, p. 95 - name only.
Endodonta (Endodonta) garrettii Ancey, Pilsbry, 1893, op. cit.,
(2), 9, p. 25.
Endodonta (Endodonta) taneae (Garrett), Pilsbry, 1893, foe. cit..
p. 26.
Diagnosis. — Shell variable in size, normally relatively small,
diameter 3.86-5.82 mm. (mean 4.89 mm.), with 4% - 8Vs normally to
very tightly coiled whorls. Apex and spire normally are moderately
and almost evenly elevated, slightly rounded above, occasionally
flattened or strongly elevated, last whorl usually descending slightly
more rapidly, sometimes drastically deflected, H/D ratio 0.327-0.535
(mean 0.428). Umbilicus broadly open, rather narrow for genus,
varying from U-shaped to V-shaped in outline, regularly decoiling,
contained 1.92-2.97 times (mean 2.58) in the diameter, sides of whorls
distinctly flattened to strongly rounded. Postnuclear sculpture of
low. rather widely spaced, slightly protractively sinuated radial ribs,
becoming reduced on lower spire and absent from all of body whorl.
Microsculpture of fine radial riblets, eight to twelve between each
pair of major ribs near termination of latter on lower spire, crossed
by exceedingly fine and crowded spiral riblets that are barely visible
under 96 x magnification. Sutures shallow, whorls compressed to
flattened laterally above periphery, which varies from having a
protruded keel to being obtusely angulated, generally sharply
angulated or keeled, compressed laterally below periphery with
352
SOLEM: ENDODONTOID LAND SNAILS
strongly rounded basal margin, umbilical margin sharply rounded to
prominently angulated, generally the former. Aperture subquad-
rangular to subcircular, depending upon whorl contours, inclined
about 25 - 30° from shell axis. Parietal barriers 2, extending
posteriorly beyond line of vision: upper moderately elevated and
bladelike, somewhat expanded and more strongly elevated on visible
posterior third, with anterior two-thirds evenly elevated until just
before edge of parietal callus; 2nd normally recessed almost to limit
of vision, equally high posteriorly, in gerontic specimens visible only
by partial destruction of palatal wall. Columellar wall without
barriers. Palatal barriers normally 4, occasionally upper missing or
additional subperipheral barrier present, recessed almost one-quarter
whorl behind lip and extending posteriorly a little less than three-
sixteenths of a whorl: lower basal in position, moderately elevated,
with gradual anterior descension; 2nd and 3rd evenly spaced on
lower palatal wall, distinctly higher than 1st, with progressively more
gradual anterior descension and further anterior prolongation; 4th,
when present, supraperipheral. midway between periphery and
parietal-palatal margin, slightly lower than 2nd, with much more
gradual anterior descension and longer anterior extension.
The presence of at least a few major radial ribs on
the upper spire, more prominent microradial sculpture,
and generally greater convexity to the upper palatal
walls combine to separate Nesodiscus taneae from the
otherwise extremely similar N. huaheinensis. Neso-
discus obolus differs in its total lack of widely spaced
major radial sculpture, generally much wider umbil-
icus, presence of only a single parietal barrier, and in
having at most 3 very deeply recessed palatals.
Description (taneae). — Shell smaller than average, with slightly
less than 6Vfe normally coiled whorls. Apex markedly protruded, early
whorls of spire flat, lower whorls descending regularly, last whorl
slightly more rapidly, H/D ratio 0.451. Apical whorls 14, sculpture
partially eroded, but traces of low, broadly rounded radial ribs
remaining. Postnuclear whorls with low, broadly rounded, somewhat
irregularly spaced, protractively sinuated radial ribs, becoming
reduced to absent on body whorl. Microsculpture of fine radial
riblets crossed by much finer and more crowded spiral riblets.
Sutures shallow, whorls flat above the acutely angled periphery,
evenly rounded below to slight shouldering at baso-umbilical margin.
Color light yellow horn with darkish, irregular flammulations.
Umbilicus widely open, U-shaped, regularly decoiling, contained 2.74
times in the diameter, whorls strongly rounded inside. Aperture
subquadrangular, flattened laterally above periphery and on basal
margin, inclined about 25° from shell axis. Parietal barriers 2: upper
a threadlike ridge for first quarter whorl, suddenly becoming higher
and weakly expanded above for posterior fifth of length; lower
parietal very deeply recessed, slightly lower elevated portion opposite
posterior part of upper parietal, barely visible from aperture.
Columellar wall without barriers. Palatal barriers 4, deeply recessed:
1st palatal at baso-columellar margin, a deeply recessed crescentic
ridge barely visible from aperture; 2nd and 3rd palatals high lamellar
ridges, short, extending one-sixteenth of a whorl, posterior end
clearly visible from aperture, with gradual anterior descension; 4th
palatal supraperipheral, a high lamellar ridge, very deeply recessed,
although extending slightly further anteriorly than 1st palatal.
Height of lectotype 2.27 mm., diameter 5.04 mm.
Lectotype. — Society Islands: Maupiti. Collected
by Andrew Garrett. ANSP 47846.
Description (garrettih. — Shell small, with &'s rather tightly
coiled whorls. Apex and spire slightly and evenly elevated, last
whorl not descending more rapidly, H/D ratio 0.397. Apical
sculpture eroded. Postnuclear whorls with sculpture of low, rather
crowded, fine, almost vertical radial ribs on spire, becoming worn off
on most of shell. Traces of microsculpture as fine radials crossed by
extremely fine spirals on part of spire and in umbilicus. Most of
surface worn. Sutures shallow, whorls flatlv and evenlv rounded
above obtusely angulated periphery, compressed laterally and almost
flat down to strongly rounded basal margin. Umbilicus broadly open,
cup-shaped, regularly decoiling, contained 2.29 times in the diameter,
margin distinctly shouldered, whorls slightly flattened inside. Color
light yellow brown, mid-spire with bright, sharply defined, narrow to
broad, dark reddish markings, mostly absent from body whorl.
Aperture subcircular, compressed laterally above and flattened below
periphery, inclined about 20° from shell axis. Parietal barriers 2,
lower deeply recessed: upper an elevated bladelike ridge, extending
posteriorly beyond line of vision, elevated and weakly expanded on
visible posterior quarter, with sharp anterior descension; 2nd recessed
almost one-quarter whorl, elevated portion higher than upper,
extending posteriorly beyond line of vision. Columellar wall without
barriers. Palatal barriers 5, recessed three-sixteenths of a whorl,
extending less than one-eighth whorl: lower basal in position,
slender, low; 2nd, 4th, and 5th with progressively more gradual
anterior descension, rather low, 5th supraperipheral; 3rd lower,
shorter, lying close to the 4th palatal. Height of holotype 1.68 mm.,
diameter 4.23 mm.
Holotype. — Society Islands. Probably Borabora.
Institut Royal des Sciences Naturelles de Belgique,
Brussels, ex Dautzenberg, Ancey.
Range. — Maupiti and Borabora Islands, Society
Islands.
Paratypes - ANSP 290111, BPBM 3359.
Material. — Society Islands: Maupiti (27 speci-
mens, BPBM 3359, ANSP 47846, ANSP 290111,
FMNH 46406, FMNH 90608, FMNH 91904, FMNH
117055). Borabora (58 specimens, BPBM 2762, BPBM
3178, BPBM 3792, BPBM 115340, BPBM 167406,
FMNH 46609, FMNH 47803, FMNH 90619, FMNH
91853): south slope Pahio-Temanu ridge (Stations
1091, 1092, 1093) at 600-800 ft. elevation (50 specimens,
BPBM 152342, BPBM 152366-7, BPBM 152386-90).
Locality unknown (111 specimens, BPBM 170946,
BPBM 170951, BPBM 170954, FMNH 46260, FMNH
91116).
Remarks. — Variation within Nesodiscus taneae is
the largest known for any species of Endodontidae.
The few specimens seen from Maupiti are relatively
uniform in size and shape, but those found on
Borabora vary amazingly (fig. 152). It is quite possible
that detailed study of local populations would have
revealed a complex of species confused under this
name, but Garrett believed that they represented one
variable form. The only recent field collections, from
the Pahio-Temanu cliff region on Borabora (Stations
1091, 1092, 1093), yielded dead shells of three different
types. The material collected by Garrett long since has
been split into small lots and dissipated among many
collections. It is impossible to use these fragmentary
sets to determine relationships of the varieties outlined
below. Transitional examples were seen, but the
probability of sub-specific differentiation remains for
investigation.
On Maupiti Island, the type locality, the shells are
acutely keeled and relatively flattened above (al-
though less so than in N. huaheinensis). Below the
periphery the shell angles sharply toward the umbi-
licus which has an obtusely rounded or only slightly
keeled margin, and the shells are comparatively
FIG. 155. a-c, Nesodiscus huaheinensis (Pfeiffer, 1853). No locality. BPBM 170947; d-f, Nesodiscus taneae (Garrett, 1872). Maupiti,
Society Islands. Lectotype. ANSP 47846. Scale lines equal 1 mm. (SH).
353
354
SOLEM: ENDODONTOID LAND SNAILS
uniform in size (table XCVI). All observed specimens
have at least traces of the major radial ribs on the
spire (fig. 155d).
On Borabora, it is possible to recognize the normal
Maupiti form with the same size range and sculpture
(table XCVI), but with the shell often slightly more
elevated (BPBM 2762, BPBM 115340, BPBM 170951).
There are also three additional more or less dis-
tinguishable forms. Form A is larger (mean diameter
5.44 mm.), with less sharply angled peripheral margin
and more rounded lower body whorl. Occasionally a
shell will be seen in which the whorls are much
narrower, more tightly coiled, and with the spire
slightly more elevated. Form B is smaller (diameter
4.27 mm.), more elevated (mean H/D ratio 0.508), and
has sinuated nodular swellings on the later whorls,
which probably are remnants of ribbing. Sometimes
the sculpture is present only on part of the shell. In
field collections, mixed sets occur (part of BPBM
152367). Form C is an apparently rare variant in which
the periphery is only slightly angled or evenly
rounded. This latter form was described as Endodonta
garrettii Ancey, 1889. A new description of the
holotype is given above. The great majority of
Mangarevan Expedition shells were form A, but
material transitional to B was also present. Mixed sets
of 2V. taneae and 2V. huaheinensis originating from the
Pease collection in the Museum of Comparative
Zoology contained many variations (fig. 152).
Garrett (1884, p. 42) mentioned that the umbilical
brood chamber cover (fig. 151) was extremely common
on Boraboran shells, although not found in his
Maupiti examples. One specimen had the brood
chamber cover intact, and upon opening was found to
have two eggs inside.
Nesodiscus huaheinensis (Pfeiffer, 1853). Figure
155a-c.
Helix huaheinensis Pfeiffer, 1853, Zeits. Malak., 10, pp. 55-56 -
Huahine, Society Islands; Pfeiffer, 1853, Monog. helic. viv., 3, p.
640; Pfeiffer, 1868, op. cit., 5, p. 222; Pfeiffer, 1876, op. cit.. 7, p.
260.
Endodonta huaheinensis (Pfeiffer), Pease, 1871, Proc. Zool. Soc.
London, 1871, p. 474; Garrett, 1884, Jour. Acad. Nat. Sci.,
Philadelphia, 9, (1), pp. 37-38, pi. 2, figs. 26, a, b, c.
Patula huaheinensis (Pfeiffer), Schmeltz, 1874, Cat. Mus.
Godeffroy, 5, p. 93; Binney, 1885, Ann. N. Y. Acad. Sci., 3, p. 89,
pi. 2. fig. L (radula).
Helix aranea "Behn" Pfeiffer, 1876, Monog. helic. viv., 7, p. 260 —
A manuscript name quoted in the synonymy of huaheinensis.
Helix (Endodonta) huaheinensis Pfeiffer, Tryon, 1887, Man.
Conchol., (2), 3, p. 61, pi. 11, figs. 92-94.
Endodonta (Endodonta) huaheinensis (Pfeiffer), Pilsbry, 1893, op.
cit., (2). 9, pp. 25, 26. pi. 9. fig. 22 (radula).
Diagnosis. — Shell smaller than average, diameter 4.90-5.82 mm.
(mean 5.17 mm.), with 5% - 6'< normally coiled whorls. Apex usually
slightly protruding above level of moderately and almost evenly
elevated spire, last whorl descending only slightly more rapidly, H/D
ratio 0.372-0.448 (mean 0.424). Umbilicus widely open, relatively
narrow for genus, U-shaped to V-shaped, regularly decoiling,
contained 2.27-2.82 times (mean 2.51) in the diameter, internal
whorls normally strongly rounded. Postnuclear whorls without major
ribbing, occasionally irregular growth striae. Microsculpture of very
wide and crowded radial riblets, crossed by barely visible and
extremely crowded spiral riblets. Sutures shallow, whorls flatly
rounded down to normally acutely angled periphery, lower palatal
margin laterally compressed, with strongly rounded basal and
umbilical margin that may be obtusely angulated. Aperture
subquadrangular, flattened above, strongly compressed laterally
below acutely to right-angled periphery, inclined about 25 - 30° from
shell axis. Parietal barriers 2, extending posteriorly beyond line of
vision: upper high and bladelike, weakly expanded and serrated
above on posterior visible third, anterior two-thirds evenly elevated
until just before anterior end; 2nd parietal recessed almost one-
quarter whorl, slightly reduced in height posteriorly, frequently not
visible from aperture without breaking palatal wall. Columellar wall
without barriers. Palatal barriers normally 4, barely visible from
aperture, recessed almost one-quarter whorl: lower basal in position,
moderately elevated, often recessed beyond line of vision; 2nd and
3rd on lower palatal wall, slightly more elevated, extending
posteriorly less than three-sixteenths of a whorl, with progressively
more gradual anterior descension; 4th supraperipheral, midway
between periphery and parietal-palatal margin, extending further
anteriorly and more elongated than 2nd palatal.
The total absence of major radial ribbing, much
less distinct microsculpture, and generally flatter
whorls separate Nesodiscus huaheinensis from its
close relative, 2V. taneae. All other species of Neso-
discus are immediately separable in having a reduced
number of apertural barriers.
Type. — Unknown. No specimens that could be
connected with Pfeiffer were seen. Until localized
material with soft parts are available, I prefer to
withhold neotype selection.
Range. — Huahine, Society Islands. Abundant in
all the large valleys (Garrett, 1884, p. 37).
Material. — Society Islands (81 specimens, BPBM
170941, BPBM 170947, BPBM 170952, BPBM 170966,
FMNH 8293, FMNH 62594): Huahine (77 specimens,
BPBM 2232, BPBM 87512, BPBM 115344, BPBM
165096, FMNH 46354, FMNH 90616, FMNH 91845,
FMNH 91872, FMNH 91145, FMNH 117046, Cardiff);
about 100 yd. inland (Station 1008) at 6 ft. elevation,
Tiva, Huahine Iti (1 specimen, BPBM 151564).
Remarks. — The dimensions of Nesodiscus
huaheinensis and 2V. taneae overlap completely and
there is no significant difference in the means (table
XCV). In 2V. huaheinensis the spire whorls are more
flattened, and there is never any widely spaced radial
sculpture. Garrett, who collected many specimens of
both species, considered taneae and huaheinensis
distinct species, although he made no direct
comparisons.
The only specimen collected in this century
(BPBM 151564) is from 100 yd. inland at Tiva,
Huahine Iti. Unfortunately, it is a dead juvenile.
Nesodiscus obolus (Gould, 1846). Figures 156a-f;
157; 158a-c.
Helix (Pitys) obolus Gould, 1846, Proc. Boston Soc. Nat. Hist., 2,
p. 175 - Tahiti, Society Islands (error); Pfeiffer, 1848, Monog.
a
Fic. 156. a-c, Nesodiscus obolus form obolus (Gould, 1846). Raiatea, Society Islands. BPBM 3786, Garrett; d-f, Nesodiscus obolus
form acetabulum (Pease, 1861). Tahiti, Society Islands (error). Lectotype. ANSP 47844. Scale lines equal 1 mm. (SH).
355
356
3.9
3.3
2.6
1.7
1.3
SOLEM: ENDODONTOID LAND SNAILS
obolus
acetabulum
celsus
D
D
D
D
O
D
D
00 O
1
4.6
5.2
5.9
6.5
diameter
FIG. 157. Scatter diagram of height and diameter in Nesodiscus obolus.
helic. viv., 1, p. 187; Gould, 1852, U.S. Explor. Exped., Wilkes,
12, pp. 53-54; Pfeiffer, 1853, Monog. helic. viv., 3, p. 145; Pfeiffer,
1859, op. cit., 4, p. 156; Gould, 1860, U.S. Explor. Exped., Wilkes,
Atlas of Shells, pL 4, figs. 50, a, b, c; Gould, 1862, Otia Conch., p.
22; Pfeiffer, 1868, Monog. helic., viv., 5, p. 222; Pfeiffer, 1876, op.
cit., 7, p. 261; Johnson, 1964, Bull. U.S. Nat. Mus., 239, p. 117.
Pitys obolus (Gould), H. and A. Adams, 1858, Genera Recent
Mollusca, 2, p. 113.
Endodonta obolus (Gould), von Martens, 1860, Die Heliceen, 2nd
ed., p. 90; Garrett, 1884, Jour. Acad. Nat. Sci., Philadelphia, 9,
(1), pp. 39-41 — Raiatea and Huahine, Society Islands. Corrects
locality of obolus to Raiatea and of acetabulum to Huahine.
Helix acetabulum Pease, 1861, Proc. Zool. Soc. London, 1861, pp.
242-243 - Tahiti, Society Islands (error); Pfeiffer, 1868, Monog.
helic. viv., 5, p. 222; Pfeiffer, 1876, op. cit., 7, p. 260.
Pithys ? celsa Pease, 1870, Jour, de Conchyl., 18, p. 396 - Raiatea,
Society Islands.
Endodonta celsa (Pease), 1871, Proc. Zool. Soc. London, 1871, pp.
455, 474.
Endodonta acetabulum (Pease), 1871, Proc. Zool. Soc. London,
1871, p. 474.
Patula barffi "Garrett" Schmeltz, 1874, Cat. Mus. Godeffroy, 5, p.
93 — A nude name for acetabulum.
Patula intermixta "Mousson" Schmeltz, 1874, foe. cit., p. 93 - A
nude name for celsa.
Helix celsa (Pease), Pfeiffer, 1876, Monog. helic. viv., 7, p. 260.
Helix (Endodonta) obolus (Gould), Tryon, 1887, Man. Conchol.,
(2), 3, p. 61, pi. 11, figs. 77-79 - The synonym barffi is misspelled
"bariffi".
Endodonta (Endodonta) obolus (Gould), Pilsbry, 1893, op. cit., (2),
9, p. 25, pi. 4, fig. 39.
Diagnosis. — Shell smaller than average, diameter 4.31-6.28 mm.
(mean 5.08 mm.), with 5'/a-7% tightly coiled whorls. Shape and spire
elevation quite variable, apex flat or barely protruding (obolus),
moderately and almost evenly elevated with slight additional
protrusion of apex (acetabulum}, or strongly elevated and rounded
above (celsus), last whorl not descending more rapidly to descending
slightly more rapidly, H/D ratio 0.273-0.647 (mean 0.432). Umbilicus
broadly open, cup-shaped to U-shaped, regularly decoiling, contained
1.75-2.69 times (mean 2.09) in the diameter, rarely with any
angulation to basal-umbilical margin. Postnuclear whorls with
sculpture of extremely fine and crowded radial ribs, too numerous to
count, whose interstices are usually equal to their width, becoming
interrupted on body whorl by irregular growth wrinkles. Micro-
sculpture visible under 96 X magnification as exceedingly fine lattice
of approximately coequal radial and spiral riblets. Sutures impressed,
whorls flatly to moderately strongly rounded down to obtusely
rounded to sharply keeled periphery, lower palatal margin rounded
to compressedly flattened, basal margin strongly rounded. Aperture
subcircular to quadrangular, inclined about 25 - 40° from shell axis.
Parietal wall with one supraperipheral, raised and threadlike barrier,
extending posteriorly for about one-half whorl; rarely a single very
weak and deeply recessed lower parietal can be seen in the extreme
posterior of the aperture. Many specimens opened for one-quarter
whorl showed no trace of 2nd parietal. Columellar wall without
barriers. Palatal wall normally without barriers, occasionally with
one or two short and weak, deeply recessed threadlike traces visible
approximately one-quarter whorl behind aperture.
The absence of any prominent and widely spaced
major radial ribbing, presence of only a single parietal,
and usually no palatal barriers serve to distinguish
SYSTEMATIC REVIEW
357
Nesodiscus obolus from either N. taneae or N.
huaheinensis. The three species show overlap in
respect to any individual measurement, but by
reference to more than one measurement, presence or
absence of sculpture on the spire, and the apertural
barriers, any specimen is immediately identifiable as
belonging to one of the three species.
Description (obolus). — Shell smaller than average, with slightly
more than 5:1/s tightly coiled whorls. Apex slightly protruded above
level of first postnuclear whorl, entire spire sunken beneath level of
body whorl, H/D ratio 0.273. Apical whorls l5/8, sculpture completely
eroded by fungus action. Postnuclear sculpture of low, very irregular,
somewhat protracted radial ribs with occasional traces of stronger
growth lines. Microsculpture mainly eroded with traces of very fine
and crowded radial riblets crossed by much finer and more crowded
spiral riblets. Sutures deeply impressed, whorls strongly shouldered
above, flattened to slightly concave above acutely angled periphery,
slightly concave below periphery to evenly rounded basal-umbilical
margin. Color light yellow horn, with regularly spaced, rather
prominent, somewhat sinuated, reddish flammulations. Umbilicus
saucer-shaped, regularly decoiling, contained 1.85 times in the
diameter. Aperture subquadrate, flattened above and on lateral
margin, evenly rounded below, inclined about 20° from shell axis.
Parietal wall with single supramedial. V-shaped barrier, extending
posteriorly beyond line of vision. Palatal barriers 3, deeply recessed
within aperture: lower palatal recessed almost one-quarter whorl,
high and bladelike, extending beyond line of vision; 2nd palatal
subperipheral, not as deeply recessed, anterior portion low and
threadlike, extending beyond line of vision; upper palatal midway
between periphery and parietal margin, equally recessed as 2nd
palatal, anterior portion low and threadlike, extending beyond line of
vision. Height of lectotype 1.38 mm., diameter 5.06 mm.
Lectotype of obolus. — Society Islands: Tahiti
(error). Redpath Museum, McGill University number
12953.
Description (acetabulum). — Shell of average size, with slightly
more than 6 tightly coiled whorls. Apex slightly elevated, whorls of
spire descending gradually and evenly, H/D ratio 0.385. Apical
whorls 1%, sculpture of low, broadly rounded radial ribs. Remaining
whorls with irregular growth wrinkles and a microsculpture of barely-
visible radial and spiral riblets. Sutures shallow, whorls flatly
rounded above periphery, somewhat flattened laterally and on
umbilical margin. Color very light yellow-white with frequent
prominent, reddish flammulations extending into the umbilicus.
Umbilicus broadly open, U-shaped, regularly decoiling, contained
2.00 times in the diameter, with the whorls strongly rounded inside.
Aperture subquadrangular, with acutely rounded periphery, obtusely
rounded basal margin, inclined slightly more than 30° from shell
axis. Parietal wall with single, low, bladelike barrier, extending
posteriorly beyond line of vision. No columellar or palatal barriers
visible. Height of lectotype 1.97 mm., diameter 5.04 mm.
Lectotype of acetabulum. — Tahiti (error), Society
Islands. ANSP 47844.
Description (celsus). — Shell of average size, with 7'^ tightly
coiled whorls. Apex and spire moderately and almost evenly
elevated, very slightly rounded above, last whorl not descending
more rapidly, H/D ratio 0.492. Apical whorls !'••>, sculpture
completely eroded. Postnuclear whorls with surface badly pitted and
scarred, sculpture visible occasionally as very fine and crowded
radial riblets, made quite irregular by growth striae. Microsculpture
visible in spots as a microlattice of extremely fine and crowded
riblets. Sutures impressed, whorls moderately rounded above,
compressed laterally, with a marked supraperipheral sulcus visible
above obtusely angled periphery, with almost evenly rounded and
only slightly compressed lower palatal wall. Baso-umbilical margin
weakly and obtusely angulated, walls of umbilicus evenly and
strongly rounded. Color very light yellow horn, with irregular,
FIG. 158. a-c, Nesodiscus obolus form celsus (Pease, 1870).
Raiatea, Society Islands. Lectotype. BPBM 3484 ex Garrett. Scale
line equals 1 mm. (MM).
358
SOLEM: ENDODONTOID LAND SNAILS
reddish flammulations that become very irregular and fade out on
body whorl. Umbilicus broadly open, cup-shaped, later whorls
decoiling less rapidly than earlier, contained 2.17 times in the
diameter. Aperture subquadrangular, markedly flattened laterally
above periphery, inclined about 35° from shell axis. Parietal wall
with single supraperipheral raised barrier, extending posteriorly
beyond line of vision, posterior visible quarter slightly more elevated,
with relatively sharp anterior descension. Columellar wall without
barriers. No palatal barriers visible from aperture. Height of
lectotype 3.03 mm., diameter 6.15 mm.
Lectotype of celsus — Raiatea, Society Islands.
BPBM 3484, ex Andrew Garrett.
Range. — Huahine and Raiatea, Society Islands.
Widely dispersed over both islands (Garrett, 1884, p.
39).
Paratypes. - ANSP 290105 (acetabulum); BPBM
3484 (celsus).
Material. — Form obolus. Raiatea (6 specimens,
BPBM 3786, Redpath Museum). Huahine (21 speci-
mens, BPBM 165097, Cardiff). No locality (33 speci-
mens, BPBM 170932, BPBM 170937, BPBM 170940,
BPBM 170953).
Form acetabulum. — Raiatea (6 specimens, BPBM
3785). Huahine (17 specimens, BPBM 3446, BPBM
115341-2, Cardiff). No locality (68 specimens, BPBM
170896, BPBM 170933-4, BPBM 170940, BPBM
170943, ANSP 47844, ANSP 290105, FMNH 46274,
FMNH 46247, FMNH 46395, FMNH 91889, FMNH
91762, FMNH 117052).
Form celsus. — Raiatea (10 specimens, BPBM
3484, BPBM 165098). No locality (8 specimens, BPBM
170939, BPBM 170973, BPBM 171012).
Remarks. — All available material consisted of
small museum sets dating from the collections of
Garrett prior to the mid-1880's. These had been
segregated into the varieties obolus, acetabulum, and
celsus. None were accompanied by exact locality data.
Garrett (1884, pp. 39-41) reviewed the previous
descriptions, corrected mistakes in type locality cita-
tions by Pease, and then stated (p. 40) "Having ...
collected hundreds of specimens, both on Raiatea and
Huahine, I do not hesitate, after a careful study of the
numerous examples, to add both acetabulum and
celsus to the synonymy of obolus."
The differences between the three forms (tables
XCV, XCVI, XCVII) are mainly in the spire elevation
and placement of the peripheral angulation or keel. In
form obolus (fig. 156b) the spire is flat or barely
elevated and the peripheral angulation is situated on
the upper quarter of the body whorl; in form
acetabulum (fig. 156e) the spire is slightly to moder-
ately elevated and the peripheral angulation is at or
slightly above the body whorl midpoint; while in form
celsus (fig. 158b) the apex and spire are almost evenly
and quite prominently elevated, with the peripheral
angulation at or even slightly below the body whorl
midpoint. Proportionate umbilical width is not materi-
ally altered by this change in spire height, but the
umbilical depth is very shallow in obolus and
progressively greater in acetabulum and celsus. The
greater spire elevation of the two latter is reflected in
their increased H/D ratio and in the partial separation
of celsus in a height-diameter scatter diagram (fig.
157). The greater overlap of obolus and acetabulum
simply reflects the minor alteration in H/D ratio
caused by a flattened instead of a slightly elevated
spire. Possibly subspecific separation would be dis-
covered through study of local populations.
Compared with both N. taneae and N. huahei-
nensis, the parietal barrier in N. obolus is both lower
and longer, extending more than one-half whorl in all
individuals opened. One example had a short 2nd
parietal that would not be visible from the unbroken
aperture, but eight others did not. The actual
frequency of 2 parietals in this species is unknown.
Similarly, about 20 per cent of those specimens opened
or subadult showed 1 or 2 low palatal barriers recessed
about one-quarter whorl. Checking for their presence
or absence required breaking off almost one-quarter of
the body whorl and destruction of more than a few
specimens was not considered justified.
Garrett stated that the Huahine specimens were
less variable than those from Raiatea. Too little
museum material retained island designations to
enable verification of this observation.
Some specimens of acetabulum or celsus could be
confused with N. huaheinensis. The latter has only
microradial ribbing, while obolus shows reticulated
microribbing between the very crowded major ribs.
Doubtful specimens can be separated by checking the
number and position of palatal barriers.
In order to stabilize the nomenclature, I have
selected lectotypes for all three varieties. Because of
the known mixing of sets in the Pease collection (now
at the Museum of Comparative Zoology) one lectotype
was chosen from a set in the Garrett collection at the
Bernice P. Bishop Museum and another from the
Academy of Natural Sciences, Philadelphia collection.
The chosen specimens match the original descriptions.
Since Garrett collected both type sets for Pease, his
material can be considered to represent Pease's
original concept. Lots of Pease material in the
Museum of Comparative Zoology are often obvious
mixtures of several species from different islands.
Selection of lectotypes from these mixtures thus would
represent pure guesswork.
Nesodiscus cretaceus (Garrett, 1884). Figure
159a-c.
Pitys ficta "Pease" Schmeltz, 1877 (not Pease, 1864). Cat. Mus.
Godeffroy, 6, p. 81 — Borabora. Society Islands (name only).
Endodonta cretacea Garrett, 1884, Jour. Acad. Nat. Sci.. Phila-
delphia, 9, (1), p. 41, pi. 2, figs. 27, a, b — Borabora, Society
Islands at 6(X) ft. elevation.
Hi'lix (Endodonta) cretacea Garrett. Tryon. 1887, Man. Conchol.,
(2). 3. pp. 66-67. pi. 11, figs. 98-100.
Endodonta (Endodonta} cretacea Garrett, Pilsbry, 1893, op. cit..
(2), 9, p. 25.
a
FIG. 159. a-c, Nesodiscus cretaceus (Garrett, 1884). Society Islands. Lectotype. ANSP 47832; d-f, Nesodiscus fabrefactus var. piceus
(Garrett, 1884). Raiatea, Society Islands. Lectotype. BPBM 4994. Scale lines equal 1 mm. (a-c, MM; d-f, SH).
359
360
SOLEM: ENDODONTOID LAND SNAILS
Diagnosis. — Shell somewhat smaller than average, diameter
5.06-6.41 mm. (mean 5.62 mm.), with 6H-7& tightly coiled whorls.
Apex slightly protruding above moderately and evenly elevated spire,
last whorl not descending more rapidly, H/D ratio 0.335-0.429 (mean
0.377). Umbilicus widely open, V-shaped, regularly decoiling, contain-
ed 1.95-2.09 times (mean 2.03) in the diameter, interior walls almost
completely flattened. Postnuclear whorls with very low, irregular,
crowded and indistinct radial riblets, accentuated on body whorl
near aperture by intrusion of growth striae. No microsculpture
visible on any specimen examined. Sutures reduced to a thin line,
whorls flat down to peripheral keel or with a weak to prominent
supraperipheral sulcus, periphery protruded into an acutely angled
keel, lower palatal wall flatly rounded down to right or obtusely
angled basal margin, columellar wall flat or at most flatly rounded.
Aperture quadrangular, flattened above periphery and on columellar
margin, lower palatal margin faintly rounded, inclined about 30 - 40°
from shell axis. Parietal wall with single, supramedial barrier,
extending posteriorly beyond line of vision, posterior visible third
greatly elevated, but not expanded above, anterior visible half a
raised threadlike ridge with gradual anterior descension. Columellar
wall without barriers. Lower palatal wall with a single, submedial,
rather deeply recessed bladelike barrier, extending posteriorly beyond
line of vision, with gradual anterior descension.
The Borabora Island Nesodiscus cretaceus differs
from the Raiatean N. fictus in its larger apex, much
lower whorl count, smaller size, and reduced barrier
size. N. fabrefactus is much larger, with very sharply
angulated baso-columellar margin and generally lacks
all apertural barriers.
Description. — Shell smaller than average, with a little more
than 6'/2 tightly coiled whorls. Apex and spire slightly elevated, sides _
of spire flat, H/D ratio 0.335. Apical whorls IVs, sculpture eroded.
Remaining whorls with growth wrinkles and a microsculpture of fine
radial ribs crossed by even finer and more crowded spiral riblets.
Sutures very shallow, whorls flat above the acutely angled periphery,
only slightly rounded down to right-angled basal margin, which then
slants evenly into the umbilicus. Color very light yellow-white with a
few narrow, reddish flammulations. Umbilicus broadly open, U-
shaped, regularly decoiling, contained 1.99 times in the diameter,
with whorls only slightly rounded inside. Aperture quadrangular with
parietal margin slightly shorter than palatal, inclined about 30° from
shell axis. Parietal wall with single barrier, high and threadlike for
first three-sixteenths of a whorl, becoming a narrow, low, bladelike
structure posteriorly and passing beyond line of vision from aperture.
No columellar barrier. Palatal wall with single, low, bladelike barrier,
extending from one-sixteenth of a whorl behind the aperture to
beyond the line of vision, located almost midway between periphery
and basal margin. Height of lectotype 1.91 mm., diameter 5.69 mm.
Lectotype. — Society Islands: Borabora at 600 ft.
elevation. Collected by Andrew Garrett. ANSP 47832.
Range. — Borabora, Society Islands. One area at
600 ft. elevation (Garrett, 1884, p. 41).
Paratypes. - ANSP 290093, BPBM 2230.
Material. — Society Islands (4 specimens, ANSP
47382, ANSP 290093): Borabora (3 specimens, BPBM
2230, Brussels).
Remarks. — Only the smaller size, larger apex, and
lower whorl count really serve to separate Nesodiscus
cretaceus from Borabora and N. fictus from Tahaa.
The apertural barriers are very similar and there are
no significant differences in shape and sculpture. The
"dentate" variety of N. fabrefactus, form piceus', is
recognized by the concave sides to the spire and very
sharp angulation at the baso-columellar margin.
N. cretaceus was cited by Garrett (1884, p. 41) as
being common at a restricted locality. Only seven
specimens were located in museum collections and no
new material was obtained by the Mangarevan
Expedition.
Nesodiscus fictus (Pease, 1864). Figures 154;
160d-f.
Helix ficta Pease, 1864, Proc. Zool. Soc. London, 1864, p. 669 - no
locality; Pfeiffer, 1868, Monog. helic. viv., 5, p. 223; Pfeiffer,
1876, op. cit., 7, p. 260.
Endodonta ficta (Pease), Pease, 1871, Proc. Zool. Soc. London,
1871, pp. 455, 474 - Raiatea, Society Islands; Garrett, 1884,
Jour. Acad. Nat. Sci., Philadelphia, 9, (1), p. 38, pi. 2, figs. 25, a,
b — Tahaa, Society Islands.
Patula ficta (Pease), Schmeltz, 1874, Cat. Mus. Godeffroy, 5, p.
207 — Raiatea, Society Islands.
Helix (Endodonta) ficta Pease, Tryon, 1887, Man. Conchol., (2), 3,
p. 62, pi. 12, figs. 5-7.
Endodonta (Endodonta) ficta (Pease), Pilsbry, 1893, op. cit., (2), 9,
p. 25.
Diagnosis. — Shell relatively large, diameter 5.62-7.32 mm.
(mean 6.47 mm.), with 7'/fe-8% very tightly coiled whorls. Apex
normally moderately and almost evenly elevated, slightly rounded
above, occasionally only slightly elevated, body whorl not descending
more rapidly, H/D ratio 0.337-0.531 (mean 0.428). Umbilicus widely
open, cup-shaped, regularly decoiling, contained 1.84-2.23 times
(mean 1.97) in the diameter, inner whorls moderately rounded.
Postnuclear sculpture of extremely fine and crowded radial ribs,
becoming irregular on body whorl because of growth striae.
Microsculpture occasionally visible under 96 X magnification as a
lattice of coequal radial and spiral riblets. Sutures shallow, whorls
flatly rounded down to prominent supraperipheral sulcus, periphery
slightly to moderately protruded into an acutely angled keel, lower
palatal margin almost flat down to strongly rounded, almost right-
angled basal margin, with columellar wall slightly but distinctly
rounded. Aperture subquadrangular, flatly rounded on all margins,
inclined about 30 - 40° from shell axis. Parietal wall with single,
supramedial, relatively low, bladelike barrier, extending posteriorly
beyond line of vision, entire visible length with approximately equal
height. Columellar wall without barriers. Palatal wall almost always
with a low, extremely deeply recessed, submedial, threadlike barrier
that extends posteriorly beyond line of vision. Many adult specimens
have the palatal barrier recessed beyond the line of vision from the
aperture, but a very few specimens seem to have lost this barrier.
The convex spire outline, distinguishable radial
sculpture, normal presence of a lower palatal, distinct
rounding to the umbilical wall and higher whorl count
combine to distinguish Nesodiscus fictus from N.
fabrefactus, which is also found on Tahaa Island. The
differences from Nesodiscus cretaceus, except for the
whorl count, larger apex, and smaller size of the latter,
are primarily in degree. N. fictus has a less strongly
angled umbilical margin and much more prominent
apertural barriers than are found in N. cretaceus.
Description. — Shell larger than average, with 7'4 tightly coiled
whorls. Apex slightly protruding, whorls of spire descending
gradually, sides of spire distinctly convex, H/D ratio 0.467. Nuclear
whorls 1V8, sculpture eroded. Remaining whorls with narrow, very
crowded, irregular radial riblets interrupted by irregular growth
wrinkles. Occasional traces of faint microspiral ribbing can be
detected. Sutures shallow, whorls flat above the slight supraperipher-
al sulcus; periphery rounded, slightly protruding; subperipheral and
columellar margins flatly rounded. Color mainly leached from shell,
slight traces of reddish flammulations remaining. Umbilicus widely
open, broadly U-shaped, contained 1.98 times in the diameter, whorls
flatly rounded inside with slight indentation of sutures. Aperture
;
FIG. 160. a-c, Nesodiscus fabrefactus (Pease, 1864). Raiatea, Society Islands. BPBM 2229. d-f, Nesodiscus f ictus Pease, 1864).
East ridge Mt. Purauti, Tahaa, Society Islands at 1,100-1,400 ft. elevation. Scale lines equal 1 mm. (SH).
361
362
SOLEM: ENDODONTOID LAND SNAILS
subquadrangular, lower palatal wall only slightly longer than
parietal, inclined about 25° from shell axis. Parietal wall with single,
slightly supramedial, threadlike raised barrier, extending posteriorly
beyond line of vision. Columellar wall without barriers. Lower
palatal wall with a single, submedial barrier, deeply recessed and
barely visible from aperture, extending posteriorly beyond line of
vision. Height of lectotype 2.86 mm., diameter 6.12 mm.
Lectotype. — Pacific Islands ( = Raiatea). USNM
24213, ex W. H. Pease "from type."
Range. — Tahaa, Society Islands.
Material. - Tahaa (5 specimens, BPBM 4956,
FMNH 91834): valley southeast of Mt. Purauti
(Station 1085) at 800 ft. elevation (265 specimens,
BPBM 152284-92); east ridge of Mt. Purauti (Station
1081) at 1,200-1,400 ft. elevation (719 specimens,
BPBM 139790-800, BPBM 145081-2, BPBM 152254).
No locality (52 specimens, BPBM 166000, BPBM
170935, BPBM 170942, BPBM 170949, BPBM 170964,
BPBM 170972, FMNH 46356, FMNH 46386, FMNH
117048, USNM 24213).
Remarks. — In the original paper describing Helix,
ficta and Helix fabrefacta, Pease stated that speci-
mens were sent both to the Cumingian collection and
the Smithsonian Institution. No specimens of this
species were located in the Cuming collection now at
the British Museum (Natural History). Only one
example was found in the United States National
Museum that dated from this period. Although
labelled as "Discus fabrefactus Pease," this can still be
considered as the type of Helix ficta Pease. Carpenter
transmitted Pease's manuscript for publication. The
original shell label is in Carpenter's handwriting. In a
footnote to Pease's description Carpenter had stated
that he thought that fabrefacta and ficta were
identical. Thus, the identification of this specimen as
fabrefactus is easily explained as being a personal
judgment of Carpenter. I have no hesitation in
considering this specimen a lectotype rather than a
neotype.
The extreme predominance of N. fictus at these
two stations does suggest that some form of zonation,
geographical or altitudinal, may exist between the two
species. Without much more data and collecting
efforts, no conclusions are possible.
As mentioned in the diagnosis, N. fictus and N.
cretaceus have much in common, with the latter being
smaller, having fewer whorls and less conspicuous
barriers. They are obviously complementary species.
This was the only species of Nesodiscus for which
abundant material that was accurately localized could
be studied. Data from three samples are included in
Table XCVI. The large size, abundant material (265
specimens from Station 1085 and 719 from Station
1081), and small pill boxes used in the Bishop Museum
mollusk collection combined to produce minor biases.
Thus the specimens in BPBM 139790 represented the
11 largest individuals selected from 719, and the 25
from BPBM 139791 represented a very small portion
of the 428 individuals catalogued as "normal adults."
The 37 shells from BPBM 152284-5-7 included 18 of 96
"normal adults" and seven (BPBM 152287) previously
selected by the BPBM staff for their relatively low
spire. Hence the slightly reduced height and H/D ratio
of the Station 1085 sample is biased by the inclusion of
low-spired individuals. Similarly, the greater height
and diameter of BPBM 139790 shells is caused by
conscious selection for large size. It is significant that
the H/D ratios and D/U ratios are virtually identical
for the Station 1081 samples, and that the diameters
for the Station 1081 and Station 1085 "normal adults"
are essentially identical.
At Station 1081, 450 (71.5 per cent) of 630 live
collected or recently dead specimens were adult, 180
(28.5 per cent) were juvenile; at Station 1085, 107 (59.2
per cent) of 181 were adult, 74 (40.8 per cent) juvenile.
Time permitted only a partial use of this material in
studying variation. Allowing for the obvious biases
documented above, there are no differences between
the two populations revealed by the measurements
utilized.
Description of soft parts. — Foot and tail slightly more than
one-half shell diameter in length, not narrower in proportion. Sole
undivided, truncated anteriorly, bluntly rounded posteriorly. Pedal
grooves typical, equal in prominence, no caudal horn or middorsal
groove present. Slime network of irregularly rectangular units, quite
prominent in tail region. Head projecting in front of foot
termination. Ommatophores typical, eyespot small. Gonopore in
typical position.
Body color yellow-white, without darker markings.
Mantle collar thin, a large glandular extension (MG) onto
pallial roof (fig. 154a). Pneumostome and anal opening typical, no
mantle lobes developed.
Pallial region (fig. 154a, b) extending slightly more than one
whorl apically, stretched out length about 13.1 mm. Lung roof clear,
without granulations. Kidney (fig. 154b, K) about 2.7 mm. long,
rectal arm equal to half total length, pericardial arm very slender
and much less than width of ureter in section opposite heart. Base of
kidney squarely rounded, lying above loop of intestine. Ureter (KD)
arising at apex of kidney, reflexing at angle of rectal and pericardial
arms, opening anterior of rectal kidney arm termination, next to
hindgut. Heart (H) lying parallel to hindgut, about 1.38 mm. long.
Principal pulmonary vein (HV) unbranched, extending into glandu-
lar extension of mantle collar.
Ovotestis (fig. 154c, G) of palmately clavate alveoli, generally
less developed than in figured example, lying at a slant to the shell
axis, extending three-quarters of a whorl above stomach reflexion.
Hermaphroditic duct (GD) very long and slender, reflexing near base
of albumen gland before entering carrefour. Albumen gland (GG)
long and slender, of small acini. Talon (GT) long and slender, much
shorter than albumen gland, fingerlike. Carrefour not differentiated.
Prostate (DG) scarcely longer than wide, two rows of acini, duct
barely visible. Uterus (UT) very slender, typically bipartite, external
differentiation very indistinct.
Vas deferens (VD) greatly enlarged from prostate duct, loosely
bound to penioviducal angle, entering penis laterally about 0.33 mm.
below penis head, usually between pilaster junction. Penial retractor
(PR) arising from columellar muscle with partial attachment to
diaphragm, inserting directly on head of penis. Penis (P) about 2.2-
2.4 mm. long, moderately to strongly swollen medially, internally
(fig. 154d, e) with two pilasters that unite apically above vas
deferens insertion, complexly expanded and/or folded in medial
expanded area, tapering down into atrium. Atrium (Y) short.
SYSTEMATIC REVIEW
363
Free oviduct (UV) much longer than prostate, slightly enlarged
above spermathecal insertion. Spermatheca (S) with head next to
base of albumen gland, shaft inserting just above penioviducal angle.
Vagina (V) not structurally differentiated.
Free muscle system very elongated, but typical in structure and
points of fusion.
Buccal mass slender, elongated, generative sac quite small.
Buccal retractors split, inserting only slightly in front of posterior
buccal mass margin. Esophagus slender and elongated, entering
stomach just above pallial cavity origin. Stomach extending just
over one whorl apically, reflexing normally to intestine which follows
typical coiling pattern compressed in approximately one-eighth whorl
between pallial cavity apex and full expansion of stomach. Hindgut
at parietal-palatal margin a little less than one-eighth whorl above
pallial cavity apex, without change in diameter from apical portion
to anus.
Digestive gland extending over 3'/2 whorls above termination of
ovotestis, very slender and elongated. Salivary glands very narrow,
lying along esophagus, not united above or touching.
(Based on BPBM 152284, BPBM 139790, five adults, 6.3-6.8 mm.
in diameter, with 7W-7V4 whorls.)
Nesodiscus fabrefactus (Pease, 1864). Figure
160a-c.
Helix fabrefactus Pease, 1864, Proc. Zool. Soc. London, 1864, p.
669 - no locality; Pfeiffer, 1868, Monog. helic. viv., 5, p. 190;
Pfeiffer, 1869, Novit. Conchol., 3, pp. 505-506, pi. 108, figs. 28-31;
Pfeiffer, 1876, Monog. helic. viv., 7, p. 210.
Endodonta fabrefacta (Pease), 1871, Proc. Zool. Soc. London,
1871, p. 474 - Raiatea, Society Islands; Garrett, 1884, Jour.
Acad. Nat. Sci., Philadelphia, 9, (1), pp. 38-39 - Tahaa and
Raiatea, Society Islands.
Patula conicava "Mousson" Schmeltz, 1874, Cat. Mus. Godeffroy,
4, p. 72 — A nude name; Pfeiffer, 1876, Monog. helic. viv., 7, p.
480 — name only.
Helix (Goniodiscus) fabrefactus Pease, Tryon, 1887, Man.
Conchol., (2), 3, p. 45, pi. 5, figs. 81-82.
Endodonta (Endodonta} fabrefacta (Pease), Pilsbry. 1893, op. cit.,
(2), 9, p. 25, pi. 5, figs. 52-53.
Nesodiscus fabrefactus (Pease), Thiele, 1931, Hand. Syst.
Weichtierk., 1, (2), p. 571, fig. 656; Zilch, 1959, Hand. Palazool.,
(6), 2, (2), p. 212, fig. 747.
Diagnosis. — Shell very large, diameter 5.56-8.50 mm. (mean 7.13
mm.), with 6'/4-8 tightly coiled whorls. Apex and early spire
moderately to strongly elevated, sides of spire usually distinctly
concave, occasionally flat, body whorl not descending to descending
moderately more rapidly, H/D ratio 0.404-0.602 (mean 0.493).
Umbilicus broadly open, regularly decoiling, last portion flaring
slightly, producing a convex outline, contained 1.70-2.17 times (mean
1.92) in the diameter, with inner margins flat to very gently rounded.
Surface essentially smooth, except for vague, irregular radial growth
wrinkles, plus exceedingly fine microreticulated secondary sculpture
under 96 X magnification. Sutures an indented line, whorls flatly
rounded down to moderately prominent supraperipheral sulcus,
periphery an acutely angled and protruded keel, lower palatal wall
flat to gently rounded, baso-umbilical margin right-angled, colu-
mellar wall almost completely flat. Aperture subquadrangular,
inclined 30-40° from shell axis, more than 45° from shell axis in
gerontic individuals. Apertural walls without any trace of barriers in
nominate race. Variety piceus differs in having a parietal and a
palatal barrier, located as in N. fictus.
Nesodiscus fabrefactus, in its typical form, is
readily recognizable by its total absence of apertural
barriers, concave outline to the spire, and extremely
sharp angulation at the baso-columellar margin.
Variety piceus, in which a long parietal and deeply
recessed palatal are present, differs from N. fictus by
its concave spire outline and sharp baso-columellar
margin. N. cretaceus from Borabora differs in its spire
outline, prominent barriers, and much less sharply
angled baso-columellar margin.
Description. — Shell large, with slightly more than 7 tightly
coiled whorls. Apex and spire strongly elevated, rounded above,
slightly convex on lower portion, H/D ratio 0.495. Apical whorls 1%,
sculpture eroded. Remaining whorls with irregular growth wrinkles
and very fine radial microriblets. Sutures very shallow, whorls flat
above supraperipheral sulcus; periphery and umbilical margins
strongly angulated, the former slightly protruding. Whorls flatly
rounded on lower palatal and umbilical margins. Color leached from
shell. Umbilicus broadly open, U-shaped, regularly decoiling,
contained 1.98 times in the diameter, whorls flattened inside, sutures
only slightly indented. Aperture subquadrangular, upper palatal
margin sinuated, inclined about 30° from the shell axis. No apertural
barriers. Height of neotype 3.59 mm., diameter 7.25 mm.
Neotype. — Society Islands: Raiatea. USNM
42427, ex W. H. Pease.
Range. — Confined to four large valleys on
Raiatea and one on the east coast of Tahaa, Society
Islands (Garrett, 1884, p. 38).
Paratypes. - USNM 42427.
Material. — Society Islands: Raiatea (47 speci-
mens, BPBM 2229, BPBM 115345, BPBM 165099,
FMNH 90612, FMNH 90634, FMNH 91859, USNM
42427). Tahaa: valley southeast of Mt. Purauti
(Station 1085) at 800 ft. elevation (3 specimens, BPBM
9574, BPBM 152293); east ridge of Mt. Purauti
(Station 1081) at 1,200-1,400 ft. elevation (7 specimens,
BPBM 139801-2). No locality (18 specimens, BPBM
170970-1, FMNH 46404, FMNH 91107).
Remarks. — Whether the form discussed below as
variety piceus is a geographic race or simply an
individual variation is unknown. Juvenile examples of
fabrefactus did not show any traces of apertural
barriers and I am inclined to consider it a subspecific
taxon. There is a great size difference in whorl width
between fabrefactus and piceus (table XCVII). Un-
fortunately, its geographic status cannot be deter-
mined.
Nearly all individuals examined had concave spire
outlines, only a few were flat, and none showed the
typical convexity seen in all other Nesodiscus. In
lacking all apertural barriers, Nesodiscus fabrefactus is
unique among the Endodontidae. While N. magnificus
and several Hawaiian Cookeconcha have only a single
parietal, W. cretaceus, N. fictus, and N. obolus have a
single parietal plus one or more additional barriers.
The slight keeling or sharp angulation of the baso-
columellar margin is equally distinctive.
No specimen dating from Pease's original descrip-
tion could be located in either the British Museum
(Natural History) or in the Smithsonian Institution,
places where Pease is believed to have donated the
types. It must be assumed that original material, if
extant, cannot be identified as such. I have chosen a
neotype from specimens received by the Smithsonian
364
SOLEM: ENDODONTOID LAND SNAILS
Institution from W. Harper Pease prior to January,
1885. Since they had the locality Raiatea, the
specimens evidently were sent after 1871, when Pease
corrected his error in locality. They may have come
from the original set, or else from material sub-
sequently collected by Andrew Garrett. In either case,
they represent the original concept of this species.
Unfortunately, the only soft parts available were
mixed with examples of N. fictus, which over-
whelmingly predominated at the stations involved.
Apparently, the typical pattern of character dis-
placement is present, with the presumed fictus having
a swollen, shorter (2.2-2.4 mm. long) penis with
enlarged pilasters, and the putative fabrefactus a
slender, longer (3.1-3.3 mm.) penis with little or no
pilaster enlargement.
Description of soft parts. — Only fragmentary extracted
individuals were available. Apparently, BPBM 139801 contained a
mixture of fictus and fabrefactus soft parts, since two penial types
were present. One conformed to the fictus type, the other was longer.
3.1-3.3 mm., more slender, with only a very weak expansion of the
pilaster about one-third of way from head. No other features of the
fragments differed from the structures in fictus. In view of the
uncertain identity of these soft parts, no figures have been prepared.
Nesodiscus fabrefactus var. piceus (Garrett, 1884).
Figure 159d-f.
Endodonta fabrefacta var. picea Garrett, 1884. Jour. Acad. Nat.
Sci., Philadelphia, 9, (1), p. 39 — west side of Raiatea, Society
Islands.
Endodonta (Endodonta} fabrefacta var. picea Garrett, Pilsbry,
1893, Man. Conchol., (2), 9, p. 25 - name only.
Diagnosis. — Shell of average size, diameter 5.82-6.21 mm. ( mean
6.06 mm.), with 6'/8-7'/4 tightly coiled whorls. Apex and spire as in the
typical form, last whorl not descending, H/D ratio 0.428-0.553 (mean
0.505). Umbilicus as in typical form, contained 1.94-2.07 times (mean
1.99) in the diameter. Sculpture, whorl contour, peripheral keel, and
aperture as in typical form. Parietal wall with single, threadlike,
almost medial barrier, slightly elevated posteriorly. Lower palatal
wall with deeply recessed, single ridgelike barrier, extending
posteriorly beyond line of vision, more elevated than parietal.
In all features of shape, sculpture, and whorl
contour, form piceus is identical with the nominate
variety. The possession of a relatively low and
inconspicuous parietal, plus a distinct palatal, both
occupying the same position as in Nesodiscus cre-
taceus and N. fictus, combine to separate piceus from
the nominate form of Nesodiscus fabrefactus.
Description. — Shell of average size, with 7'<d tightly coiled
whorls. Apex and spire moderately and evenly elevated, sides of spire
distinctly concave, body whorl not descending more rapidly, H/D
ratio 0.543. Embryonic whorls and early spire with surface sculpture
completely eroded. Lower spire macroscopically smooth, part of body
whorl with irregular growth lines and traces of microradial ribbing.
Sutures not indented, whorls flat down to relatively prominent
supraperipheral sulcus. Periphery distinctly protruded into an
acutely angled keel, lower palatal margin strongly compressed
laterally, flatly rounded down to keeled baso-columellar margin,
with columellar wall flatly rounded. Color light yellow-white, with
irregular and widely scattered reddish flammulations below pe-
riphery of body whorl and in umbilicus. Umbilicus broadly open,
regularly decoiling, last two whorls somewhat flaring outward,
contained 2.07 times in the diameter. Aperture quadrangular,
inclined about 30° from shell axis. Parietal wall with single, medial,
threadlike barrier, extending posteriorly beyond line of vision,
becoming weakly elevated on visible posterior quarter. Columellar
wall without barriers. Lower palatal wall with single, deeply recessed,
bladelike barrier, extending posteriorly beyond line of
vision and much higher than parietal. Height of lectotype 3.39 mm.,
diameter 6.21 mm.
Lectotype. — Society Islands: Raiatea. West side of
island. Collected by Andrew Garrett. BPBM 4994.
Range. — West side of Raiatea, Society Islands.
Material. — Raiatea (6 specimens, BPBM 4994,
BPBM 9573).
Remarks. — The possession of a distinct parietal
and one palatal separates Nesodiscus fabrefactus form
piceus from the typical variety. The actually smaller
size of the former (mean diameter of piceus is 6.06
mm., of fabrefactus 7.46 mm.) is confirmed by the
essentially identical whorl count (table XCV) and
much wider early whorls (table XCVII) in the
nominate race. I suspect that piceus probably is a
valid subspecies, but without new collections its status
as a variety should be maintained. Form piceus
probably is nearer the ancestral species and fabre-
factus is a derived taxon. The probability of a dwarfed
fabrefactus regaining apertural barriers that are
identical in shape and position to those found in N.
cretaceus and N. fictus seems quite small. It is much
more probable that with increasing size the reduced
barriers still present in piceus were lost by fabrefactus.
Nesodiscus magnificus, new species. Figure 161a-c.
Diagnosis. — The very large size, 11 mm. in diameter with 7
whorls, relatively narrow and flat-sided umbilicus, D/U ratio 2.87,
strongly protruded keel, and convex spire, H/D ratio 0.454, combine
with the single supramedial parietal barrier and complete absence of
columellar or palatal barriers to separate Nesodiscus magnificus
from other Society Island species. The only species that even
approaches it in size, Nesodiscus fabrefactus, has the sides of the
spire concave, the umbilicus much wider (D/U ratio less than 2.25),
and the baso-columellar margin keeled or very strongly angled.
Description. — Shell very large, with 7'^ normally coiled whorls.
Apex and spire strongly elevated, rounded above, body whorl not
descending more rapidly, H/D ratio 0.454. Apical whorls and early
spire with sculpture completely eroded. Lower spire badly worn,
showing occasional traces of low, rounded, indistinct radial ribs,
whose interstices are about twice their width. No trace of
microsculpture visible on shell surface. Sutures consisting of an
impressed line slightly below outer edge of keel, whorls concave down
to strongly protruded threadlike keel, supra- and subperipheral sulci
prominent, lower palatal wall flatly rounded down to very strongly
rounded baso-columellar margin, with columellar wall strongly
flattened. All color leached from shell. Umbilicus broadly open, U-
shaped, slightly decoiling, last whorl decoiling a little more rapidly,
contained 2.97 times in the diameter, inside whorls strongly
flattened, sutures indented. Aperture subquadrangular, inclined
about 40° from shell axis. Parietal wall with single, supramedial,
bladelike barrier, extending posteriorly beyond line of vision,
posterior visible quarter slightly more elevated, anterior portion a
raised lamellar ridge until shortly before anterior termination. No
columellar or palatal barriers. Height of holotype 5.10 mm., diameter
11.19 mm.
SYSTEMATIC REVIEW
365
a
FIG. 161. a-c, Nesodiscus magnificus, new species. Station 1091,
south slope of Pahio-Temanu ridge, Borabora, Society Islands at 800
ft. elevation. Holotype. BPBM 152341. Scale line equals 1 mm. (SH).
Holotype. — Society Islands: Borabora, Station
1091, south slope of Pahio-Temanu ridge, at 800 ft.
elevation. Collected by Gessler and St. John on a ledge
over rock overhang, on October 13, 1934. BPBM
152341.
Range. — Borabora, Society Islands.
Material. — Only the holotype is known.
Remarks. — Only the Hawaiian Nesophila tiara
(Mighels, 1845) and the Mangareva Island Gambio-
donta grandis exceed the size of Nesodiscus mag-
nificus. An occasional specimen of Endodonta fricki
(Pfeiffer, 1858) will reach 10 mm. in diameter, but
otherwise only Libera /acquinoti from an unknown
locality and possibly Nesodiscus fabrefactus reach 9
mm. in diameter (see Garrett, 1884, p. 38).
Nesodiscus magnificus shows several differences
from the common Nesodiscus pattern. The keel is
much sharper and more strongly protruded, producing
an actual concavity on the upper palatal wall; the
umbilicus is narrower, typically U-shaped and with the
whorls much more strongly flattened internally than
in the other more narrowly umbilicated species;
sculptural remnants approach the N. taneae pattern
rather than those very fine and crowded ribs seen in
the other taxa; the baso-columellar margin is strongly
rounded, but not keeled or angled; and the apex is not
distinctly protruded above the spire.
Unfortunately, only the one dead, quite worn
individual collected in leaf litter is known.
Genus Nesophila Pilsbry, 1893
Man. Conchol.. (2). 9, p. 27.
Medium-sized to very large Endodontidae with moderately to
greatly reduced sculpture. Apex and spire slightly to moderately
elevated, last whorl descending a little more rapidly. Umbilicus
widely open, regularly decoiling, with distinctly angulated margin
and flattening of the inner whorls. Periphery of body whorl rounded
to obtusely angulated, usually compressed laterally above and below.
Parietal wall with many threadlike lamellar traces that extend
posteriorly beyond line of vision. Columellar and palatal walls
without barriers. Pallial region typical. Genitalia with short, ovoid
talon, a very short vagina, and simple uterus. Penial retractor
attached partially to diaphragm, partially to columellar muscle apex.
Penis long, nearly uniform in diameter, with two large pilasters
connected above and below, forming an elongately oval, "donut"-
shaped stimulatory pad. Jaw of completely fused plates centrally,
traces of sutures visible at outer edge. Radular teeth typical in form,
except outer marginals tending to square basal plates, large in size.
Type species. — Helix tiara Mighels, 1845 (original
designation).
Described as a section of Endodonta to be used for
all Polynesian species in which the columellar and
palatal barriers were lost, Nesophila is restricted here
to a small complex from Kauai. The species share a
widely open umbilicus with margined shoulder,
rounded or obtusely angulated periphery, complete
loss of palatal and columellar barriers, with the
parietals split into a number of threadlike traces.
Many species of Cookeconcha have lost the columellar
366
SOLEM: ENDODONTOID LAND SNAILS
and palatal barriers, but retain 1 or 2 large to
threadlike parietals. Derivation of Nesophila from a
generalized Cookeconcha-type ancestor requires, essen-
tially, only increase in size, reduction in sculpture,
intensification of contour trends, and splitting of the
parietals.
Somewhat similar modifications of apertural bar-
riers are seen in other parts of the Pacific. Austral-
donta radiella from Rurutu and Tubuai, Austral
Islands, has lost the columellar and palatals, with the
parietals split into 7-17 threadlike traces, only one of
which is enlarged. The Rapan Opanara megomphala
has less drastically split parietals, but the palatal and
columellar wall covered with threadlike traces. The
Marquesan Taipidon centadentata and Planudonta
intermedia still retain a few elevated parietals and
palatals, but have most of the palatals split into
threads. Examination of anatomical and other shell
features indicates that the barrier similarities are
convergent, since each form shows clear relationships
to local species.
The morphologic gaps between Endodonta, Cook-
econcha, and Nesophila are much larger than the gaps
between species within the genera.
Nesophila tiara (Mighels, 1845). Figure 165c-g.
Helix tiara Mighels, 1845, Proc. Bost. Soc. Nat. Hist., 2, p. 19 -
Kauai; Pfeiffer, 1848. Mon. helic. viv., 1, p. 85; Pfeiffer, 1850,
Zeit. Malak., 6, pp. 70-71; Pfeiffer, 1853, Mon. helic. viv., 3, pp.
98-99; Pfeiffer, 1853, Syst. Conchyl. Cab., (1), 12, (3), p. 293, pi.
125, fig. 9-11 (plate issued in 1853); Reeve, 1854, Conchol. Icon.,
Helix, pi. 109, fig. 611; Pfeiffer, 1859, Mon. helic. viv., 4, p. 93;
Pfeiffer, 1868, Mon. helic. viv., 5, p. 156; Pease, 1871, Proc. Zool.
Soc., London, 1871, p. 475; Pfeiffer, 1876, Mon. helic. viv.. 7, p.
163; Tryon, 1887, Man. Conchol., (2), 3, p. 38, pi. 8, figs. 25-27;
Johnson, 1949, Occ. Pap. Moll., 1, (14), p. 229, pi. 27, fig. 23.
Endodonta tiara (Mighels), von Martens, 1860, Die Heliceen, ed. 2,
p. 90; Pilsbry, 1893, Man. Conchol., (2), 9, p. 27.
Patula (Stepsanoda) (sic) tiara (Mighels), Clessin, 1881, Nomen.
Helic. viv., p. 94.
Champa tiara (Mighels), Ancey, 1889, Bull. Soc. Malacol. France,
6, p. 175; Baldwin, 1893, Catalogue Land and Fresh Water
Shells, p. 15.
Endodonta (Nesophila) tiara (Mighels), Sykes, 1900, Fauna
Hawaiiensis, Moll., 2, (4), p. 291.
Diagnosis. — Shell very large, diameter 10.72-12.55 mm. (mean
11.29 mm.), with SVi-SVs normally coiled whorls. Apex and spire
slightly and almost evenly elevated, body whorl descending slightly
more rapidly, H/D ratio 0.500-0.630 (mean 0.560). Umbilicus widely
open, V-shaped, regularly decoiling, margin distinctly angled with
inner whorls flattened, contained 2.91-3.28 times (mean 3.14) in the
diameter. Apical whorls smooth, without trace of sculpture under
96 X magnification. Postnuclear whorls basically with irregular
growth wrinkles, which obscure an apparent pattern of very low and
inconspicuous radial ribs on most of spire, becoming completely
dominated by growth wrinkles on body whorl. No microsculpture
visible. Sutures impressed, whorls compressed laterally above and
below rounded periphery, umbilical margin angulated, columellar
wall distinctly flattened. Aperture subcircular, compressed laterally
above and below rounded periphery, inclined about 25 - 30° from
shell axis. Parietal barriers 7-11, usually 9, approximately equal-sized
threadlike traces extending posteriorly beyond line of vision.
Columellar and palatal walls without barriers.
Range. — Kauai, Hawaiian Islands.
Lectotype. — Kauai, Hawaiian Islands. MCZ
176994.
Material. — Hawaiian Islands (2 specimens,
FMNH 7678, FMNH 91893): Kauai (2 specimens,
FMNH 46399); upper Kaapoko, Hanalei at 1,300 ft.
elevation (2 specimens, BPBM 93905); south branch,
north fork, Wailua River, Wailua (3 specimens, BPBM
81310).
Remarks. — The very large size of Nesophila tiara
serves to separate it from the other described species,
which range from 4-7 mm. in diameter with essentially
identical whorl counts. Study of the abundant tiara
material in the Bernice P. Bishop Museum may lead
to recognition of several subspecies on Kauai.
The anatomy of N. tiara basically is the same as
that of Endodonta fricki. The position of the ovotestis
lying perpendicular (fig. 165d) to the plane of coiling,
rather than at an angle (fig. 163c) to the plane of
coiling as in most Endodontidae, probably is a simple
correlative of the very large size with low whorl count
reached by Nesophila tiara. The greater development
of the penial pilasters with stronger lateral extensions
of the free edges probably is a result of a similar cause.
Possibly the smaller, shorter talon of N. tiara may
have more systematic significance.
Description of soft parts. — Foot and tail long and slender,
length about equal to shell diameter, very slightly tapering
posteriorly, bluntly rounded behind. Sole undivided. Pedal grooves
deep, rather high on side of foot, no caudal horn or middorsal groove
present. Slime network prominent, proportionately very fine. Head
projecting in front of truncated foot. Ommatophores long, with large
eyespots. Gonopore directly behind right rhinophore, a very narrow
vertical slit.
Body color yellowish-white, without darker markings.
Mantle collar (MC) thick, without any glandular extension onto
pallial roof. Pneumostome (LP) masked by thickened edges of
mantle collar, no mantle lobes as such developed. Anus (A) opening
above pneumostome in angle of mantle collar.
Pallial region (fig. 165c) extending about three-quarters of a
whorl apically, nearly 13 mm. long. Lung roof clear, without
granulations. Kidney (K) elongately triangular, about 5-6 mm. long,
with very short portion reaching hindgut. Ureter (KD) on inner
margin of kidney, opening at point where kidney touches hindgut.
Heart (H) about half length of kidney, lying parallel to hindgut.
Principal pulmonary vein (HV) rather wide, without obvious
branching, reaching to edge of mantle collar. Hindgut (HG) not
tapered, following parietal-palatal margin only to apex of pallial
cavity, then curving outwards across albumen gland.
Ovotestis (fig. 165d, e, G) of many palmately clavate clumps of
alveoli strung in overlapping clusters along a single collecting tubule,
stopping well short of soft parts apex. Individual clusters at right
angle to plane of coiling. Hermaphroditic duct (GD) very slender at
first, moderately expanded medially, narrowing considerably just
before reflexing slightly to enter carrefour. Albumen gland (GG)
small, lying above head of prostate and uterus. Talon (fig. 165f) with
ovoid head and short shaft before entering carrefour (X), lying
partially at inner margin of albumen gland, partially buried in
albumen gland. Carrefour short and inconspicuous. Prostate (DG)
with several rows of large acini opening into a narrow tube, upper
section partially wrapped around uterus. Uterus (UT) bipartite,
slender upper section partially enfolded by prostatic acini, lower
expanded chamber very thinwalled, tapering gradually to free
oviduct well below end of prostate.
SYSTEMATIC REVIEW
367
Vas deferens (VD) slender, lightly bound to penioviducal angle,
entering penis a little more than 1 mm. below penial apex, below free
edge of one pilaster. Penial retractor (PR) arising from diaphragm at
apex of pallial cavity opposite base of spermathecal head, inserting
directly onto penis head. Some fibers from point of origin also run to
columellar muscle. Penis (P) slightly tapered apically, mostly with
equal diameter until sharp constriction just before atrium, 8.2-10.0
mm. long, internally (fig. 165g) with two large pilasters, united
apically and basally, both with their outer edges free and elongated,
inner margins usually crenulated. Atrium (Y) short and rather wide.
Free oviduct (UV) much shorter than prostate, but much longer
than shown in Figure 165d. Ratio of prostate length to postprostatic-
free oviduct length about 5:4.5. Spermatheca (S) with head outside
and below albumen gland above apex of pallial cavity, shaft
inserting onto free oviduct above penis junction. Vagina (V) short,
but distinctly recognizable as a morphologic unit.
Free muscle system typical, but massive, particularly the tail
fan. Right ommatophoral retractor passing through penioviducal
angle, uniting with right rhinophoral retractor about three-eighths of
way to columellar margin. Tentacular retractors unite laterally on
each side of tail fan about halfway from head to apex of columellar
muscle. Columellar muscle extending one-eighth whorl above tip of
albumen gland.
Buccal mass as in E. fricki. Buccal retractors split, uniting just
posterior to buccal mass, joining columellar muscle at its apex.
Stomach starting less than 1 mm. above apex of pallial cavity,
extending one whorl apically. Intestinal coiling as in E. fricki.
Hindgut typical, except for slight extension above apex of pallial
cavity.
Digestive glands as in E. fricki. Salivary glands typical, uniting
weakly above esophagus.
Jaw about 0.7 mm. long, of completely fused plates, except at
outer margins where traces of sutures can be detected. Concentric
striations very prominent.
Radula with central about 14ft long, 9-10/i wide, with 8 laterals
and more than 8 marginals. Outer marginals with basal plates more
nearly square than usual.
(Based on BPBM 81310, four whole and several fragmentary
examples.)
Nesophila baldwini (Ancey, 1889)
Charopa baldwini Ancey, 1889, Bull. Soc. Malacol. France, 6, p.
176 - Sandwich Islands; Baldwin, 1893, Catalogue Land and
Fresh Water Shells, p. 15.
Endodonta baldwini (Ancey), Pilsbry, 1893, Man. Conchol., (2), 9,
p. 26.
Endodonta (Nesophila) baldwini (Ancey), Sykes, 1900, Fauna
Hawaiiensis, Moll., 2, (4), p. 289 — Hawaiian Islands.
Range. — Probably Kauai, Hawaiian Islands.
Material. — None.
Remarks. — The type specimen, about 4 mm. in
diameter with 4% whorls, was obtained by Ancey from
John H. Thomson and possibly originated with A. A.
Gould. The description is that of a small Nesophila
and there is little doubt that it belongs to this group.
Nesophila distans (Pease, 1866)
Helix distans Pease, 1866, Amer. Jour. Conchol., 2, (4), p. 290 -
Sandwich Islands; Pfeiffer, 1876, Mon. helic. viv., 7, p. 262;
Tryon, 1887, Man. Conchol., (2), 3, p. 60.
Patula (Endodonta) distans (Pease), Clessin. 1881, Nomen. helic.
viv., p. 95.
Pitys distans (Pease), Ancey, 1889, Bull. Soc. Malacol. France, 6,
p. 185; Baldwin, 1893, Catalogue Land and Fresh Water Shells,
p. 16.
Endodonta distans (Pease), Pilsbry, 1893, Man. Conchol., (2), 9, p.
27.
Endodonta (Nesophila) distans (Pease), Sykes, 1900, Fauna
Hawaiiensis, Moll., 2, (4), p. 290 - Kauai.
Range. — Kauai, Hawaiian Islands.
Material. — None.
Remarks. — About 7 mm. in diameter, with 4-5
whorls, this undoubted species of Nesophila is inter-
mediate in size between the smaller baldwini and large
tiara.
Nesophila capillata (Pease, 1866)
Helix capillata Pease, 1866, Amer. Jour. Conchol., 2, p. 292 -
Sandwich Islands; Pfeiffer, 1876, Mon helic. viv., 7, p. 197.
Pitys capillata (Pease), Pease, 1871, Proc. Zool. Soc. London, 1871,
p. 474 — Kauai.
Patula (Gonyodiscus) capillata (Pease), Clessin, 1881, Nomen.
Helic. viv., p. 92.
Charopa capillata (Pease), Ancey, 1889, Bull. Soc. Malacol.
France, 6, p. 175; Baldwin, 1893, Catalogue Land and Fresh
Water Shells, p. 15 — Kilauea and Kealia, Kauai.
Endodonta (Nesophila) capillata (Pease), Sykes, 1900, Fauna
Hawaiiensis, Moll., 2, (4), p. 289.
Nesophila capillata (Pease), Cockerel!, 1925, Nautilus, 38, (3), p.
82 — head of Anahola Valley, near waterfall, Kauai, Hawaiian
Islands.
Diagnosis. — Shell large, diameter 4.24-4.75 mm. (mean 4.46
mm.), with 45/s-5 normally coiled whorls. Apex and most of spire
slightly and evenly depressed below level of penultimate whorl, body
whorl descending rapidly, distinctly below level of penultimate
whorl, H/D ratio 0.488-0.517 (mean 0.500). Umbilicus widely open, V-
shaped, regularly decoiling, contained 2.34-2.63 times (mean 2.51) in
the diameter, with sides distinctly flattened. Postnuclear sculpture of
widely spaced, low, narrow, protractively sinuated radial ribs, 39-44
(mean 41.0) on the body whorl, whose interstices are 5-9 times their
width. Microsculpture of very fine, rather widely spaced radial
riblets, six to ten between each pair of major ribs, with barely visible
traces of extremely crowded spiral riblets. Secondary spiral sculpture
of about 10 narrow spiral cords that "notch" both major and micro-
radials and are located from upper shoulder to umbilical margin, but
not on shell base or near suture. Sutures deep, whorls strongly
rounded above, shouldered on umbilical margin, with laterally
compressed and evenly rounded outer margin. Aperture subcircular,
compressed laterally, inclined about 10° from shell axis. Parietal wall
usually with eleven or twelve threadlike traces that extend
posteriorly beyond the line of vision, occasionally with only eight
traces. Columellar and palatal walls without barriers.
The smaller size, distinct radial ribbing, and
peculiar secondary spiral cording at once separate
Nesophila capillata from the much larger N. tiara
with its greatly reduced radial ribbing and lack of
secondary spiral cording. While the Oahu Cooke-
concha hystrix has almost identical sculpture, the
palatal barriers and 2 large parietals distinguish that
species.
Description. — Shell large, with 5 normally coiled whorls. Apex
and spire slightly and regularly depressed below level of penultimate
whorl, body whorl descending rapidly, H/D ratio 0.517. Apical whorls
1'4, macroscopically smooth above, umbilical side showing smooth
first part, then very fine radial ribbing. Postnuclear whorls with low,
narrow, widely spaced, sharply outlined, protractively sinuated radial
ribs, 44 on the body whorl, whose interstices are 5-9 times their
width. Microsculpture of fine radial riblets, six to ten between each
pair of major ribs, with barely visible traces of extremely crowded
spiral riblets under 96 x magnification. Secondary microsculpture of
368
SOLEM: ENDODONTOID LAND SNAILS
11 widely spaced, narrow, spiral cords that "notch" both major and
microradials, present from top of whorl shoulder down to umbilical
margin, but absent from umbilicus and suture areas. Sutures deep,
whorls strongly rounded above, slightly shouldered on umbilical
margin, evenly rounded on laterally compressed outer margin, sides
of umbilicus flattened. Color light yellow horn, with broad, irregular,
zigzagged, reddish flammulations that fade out on shell base.
Umbilicus broadly open, V-shaped, regularly decoiling, contained
2.47 times in the diameter, with whorl sides distinctly flattened.
Aperture subcircular, compressed laterally, strongly rounded above
and below, inclined about 10° from shell axis. Parietal wall with
twelve threadlike traces that extend posteriorly beyond line of vision,
spacing irregular, those on lower part closer together than those on
upper. No columellar or palatal barriers. Height of lectotype 2.45
mm., diameter 4.75 mm.
Lectotype. — Sandwich Islands ( = Hawaiian Is-
lands). ANSP 1975a, ex A. D. Brown, W. H. Pease.
Range. — Kauai, Hawaiian Islands.
Paratype. - ANSP 1975.
Material. — Hawaiian Islands (8 specimens,
BMNH, ANSP 1972, ANSP 1975, FMNH 155932).
Remarks. — The much larger Nesophila tiara
lacks the secondary spiral cording, has the main radial
sculpture reduced, and the microsculpture absent. Its
umbilical walls are less clearly flattened and the
parietal traces usually number nine, instead of the
eleven to twelve recorded in N. capillata.
Cookeconcha hystrix (Pfeiffer, 1846) from Mt.
Konahuanui, Oahu, has exactly the same type of
sculpture as in N. capillata, except that the major
radials are more elevated and less widely spaced.
Numerous shape and barrier changes distinguish the
two species, but the essentially exact correspondence
in sculpture emphasizes the unitary nature of the
Hawaiian endodontid radiation.
Genus Kondoconcha, new genus
Endodontidae with typical apical and microsculpture, major
radial ribs prominent on mid-spire, greatly reduced on lower spire
and absent from body whorl and shell base. Whorls about 6%, rather
tightly coiled. Apex and spire moderately and evenly elevated, body
whorl often strongly deflected below periphery, which is nearly right
angled with a weak supraperipheral sulcus. Umbilicus narrowly open,
U-shaped, barely decoiling. Parietal barriers 2, each with at least one
accessory ridge on each side, plus several short accessory traces on
parietal wall. Columellar barrier very large, parallel to plane of
coiling, with a lower accessory trace. Palatal barriers 5, with many
accessory traces. Anatomy unknown.
Type species. — Kondoconcha othnius, new spe-
cies.
In general appearance, Kondoconcha could be
confused with the more narrowly umbilicated Neso-
discus, such as N. taneae and N. huaheinensis, or the
Hawaiian Endodonta binaria (Pfeiffer, 1856). Its
numerous apertural barriers and typical micro-
sculpture distinguish it from the Nesodiscus, while the
many accessory traces, completely different barrier
form, and umbilical shape effectively separate it from
any species of Endodonta. The presence of only 2
parietals and the angulated periphery suggest that
Kondoconcha might be related to Orangia. The
normally sculptured genus Orangia also differs sig-
nificantly in its unusual form of umbilical closure and
complete absence of accessory traces. Orangia species
also have (except rarely) only 4 palatals. Of the Rapan
species, only Opanara bitridentata and O. dupli-
cidentata have accessory traces. Both differ in details
of barrier structure, have normal sculpture, and either
wider (duplicidentata) or differently shaped (bitriden-
tata) umbilici. Kondoconcha shares the size, 2 parietal
barriers, shape and peripheral angulation of Orangia,
has the accessory traces found in a few Opanara, but
differs from all Rapan species in its marked sculptural
reduction and presence of lateral accessory barriers on
both the upper and lower side of each parietal (fig.
108c, d).
I consider that the similarities to Orangia are the
result of parallel evolution, since both, almost cer-
tainly, were derived from an Opanara-type ancestral
stock. The totally different sculpture and umbilical
structure of Orangia (fig. 123a, b) when compared
with Kondoconcha (fig. 162a, c) is striking. Combined
with the difference in apertural barriers, generic
recognition is required.
Although three sets of partly extracted soft parts
were borrowed for study, no satisfactory data on
anatomy was obtainable. Three whole specimens had
dried out at a previous time, while the fragmentary
examples were squashed flat. A single penis, minus
retractor and an unknown portion of its lower shaft,
was separated from one fragment. It seemed to have
the two high and narrow pilasters, but could not be
figured and its conditon was too poor for formal
description. What could be seen was fully consistent
with the hypothesized derivation from Opanara, but
the evidence is very meager.
So much of this study was possible only because
of the labors by Yoshio Kondo that dedication of this
very striking genus to him is a small token of
appreciation.
Kondoconcha othnius, new species. Figures 108
c-d; 162.
Diagnosis. — Shell large, diameter 3.81-4.24 mm. (mean 4.06
mm.), with 6%-63/4 rather tightly coiled whorls. Apex and spire
moderately and evenly elevated, sometimes slightly flattened above,
last whorl barely to strongly deflected below periphery, H/D ratio
0.548-0.601 (mean 0.567). Umbilicus narrow, U-shaped, scarcely
decoiling. contained 5.00 - 6.40 times (mean 5.55) in the diameter.
Postnuclear sculpture of broad, prominent, low, protractive radial
ribs that become greatly reduced in prominence on the lower spire
and are absent from body whorl. Base of shell smooth and shiny,
without traces of radial sculpture. Microsculpture of exceedingly fine
and crowded radial riblets crossed by even finer and more crowded
spiral riblets. No secondary microsculpture. Sutures shallow, whorls
strongly rounded above to weak supraperipheral sulcus, periphery
nearly right angled, weakly protruded, lower palatal margin strongly
and evenly rounded to sharply rounded baso-columellar margin.
Aperture ovate, flattened laterally above protruded periphery,
inclined about 20° from shell axis. Parietal barriers 2, extending
posteriorly more than one-quarter whorl, each with lateral accessory
ridges, plus three to five (usually three) short accessory traces on the
SYSTEMATIC REVIEW
369
a
abc
FIG. 162. a-c, Kondoconcha othnius, new species. Station 346,
Mt. Tavaitahu, Rapa Island, Austral Islands. Holotype. BPBM
142462. Scale line equals 1 mm. Drawings by YK reproduced through
the courtesy of Bernice P. Bishop Museum.
parietal wall; upper parietal very high and slender, expanded and
serrated above on posterior five-eighths, with gradual anterior
descension, and a low ridgelike, expanded and serrated accessory
lamella on each side of main blade (fig. 108c-d); 2nd parietal slightly
lower than 1st, more strongly expanded and serrated above on
posterior half, with sharp descension to a strongly elevated
threadlike ridge that terminates opposite anterior end of upper
parietal, with weak threadlike accessory denticles on upper and lower
basal edges of barrier. Accessory traces short, threadlike, deeply
recessed within aperture, one situated above upper parietal, one
between 1st and 2nd parietal, and one below 2nd parietal. Additional
parietal traces occasionally developed above 1st and below 2nd
parietal. Columellar barrier very high and bladelike, broadly
expanded and serrated above posteriorly, lying parallel to plane of
coiling, with extremely abrupt anterior descension nearly to edge of
lip margin; a deeply recessed, threadlike, expanded accessory trace
situated just above baso-columellar margin. Palatal barriers 5,
extending posteriorly nearly three-sixteenths of a whorl, with eight
to ten accessory traces, 4th palatal greatly reduced in size, first 3
very large; 1st palatal high, bladelike, expanded, serrated, and
flattened above, with gradual anterior descension; 2nd palatal equal
in height to 1st, expanded and serrated portion shorter, with more
gradual anterior descension; 3rd palatal slightly higher than 2nd,
expanded and serrated portion further reduced in length, with more
gradual anterior descension; 4th palatal a raised threadlike ridge,
only weakly expanded and serrated above, subperipheral, situated
slightly below level of upper parietal; 5th palatal larger than 4th,
supraperipheral, a raised lamellar ridge, weakly expanded and
serrated above, less recessed within aperture. Palatal traces variously
located, normally one below 1st palatal, two above 5th palatal, and
one or two between each pair of palatals.
The essentially complete loss of ribbing on the
shell base, great reductions of radial ribbing on the
lower whorls, and development of accessory traces on
the sides of the parietal barriers are a combination of
characters unique among the Endodontidae. The only
species with which Kondoconcha othnius can be
confused are Endodonta binaria (Pfeiffer, 1856) from
Kauai, Hawaiian Islands, which differs in the form and
length of the apertural barriers, and possibly some of
the Orangia, which differ in having a closed umbilicus
and normal radial sculpture.
Description. — Shell rather large, with 6:I4 relatively tightly
coiled whorls. Apex and spire strongly and evenly elevated, very
slightly rounded above, last whorl deflected below periphery, H/D
ratio 0.601. Embryonic whorls with sculpture eroded. Whorls 2%-5
with low. indistinct, broad radial ribs, that after 5th whorl become
indistinguishable except for occasional irregularities on periphery.
Base of shell smooth and shiny, without trace of microsculpture.
Microsculpture of extremely fine radial and even finer and more
crowded spiral riblets. Sutures shallow, whorls rounded down to
prominent supraperipheral sulcus. Periphery almost right angled,
slightly protruded, lower palatal and basal margin strongly and
evenly rounded. Color light greenish-horn, with broad, irregular,
reddish flammulations that fade out on last part of body whorl and
are greatly reduced on shell base. Umbilicus very narrow, scarcely
decoiling, last whorl with irregular outline, contained 6.40 times in
the diameter. Aperture ovate, slightly flattened laterally above
protruded periphery, inclined about 20° from shell axis. Parietal
barriers 2, extending posteriorly more than one-quarter whorl, with
three short, recessed accessory traces on the parietal wall and two
accessory ridges on the sides of both major parietals: upper parietal
high and bladelike. slender, expanded and serrated above on
posterior five-eighths, with gradual anterior descension until just
before anterior end, and two accessory ridges, one on upper and one
on lower side of main blade base; 2nd parietal with posterior
elevated portion reduced in height, more strongly expanded and
370
SOLEM: ENDODONTOID LAND SNAILS
serrated above, with sharp anterior descension to an elevated
ridgelike anterior termination, weak threadlike accessory traces on
each side of main lamellar blade base. Columellar barrier very high,
broadly expanded and serrated above, lying parallel to plane of
coiling, abruptly descending almost to edge of columellar lip, a single
deeply recessed raised threadlike ridge at columellar basal margin as
an accessory trace. Palatal barriers 5, with eight accessory traces
present: lower palatal high, bladelike, expanded, serrated and
flattened above, with gradual posterior and anterior descension; 2nd
and 3rd palatals with expanded elevated portions reduced in length,
more gradual anterior descension; 4th palatal a raised threadlike
ridge, subperipheral, with exceedingly gradual anterior descension;
5th palatal supraperipheral, much higher than 4th, but lower than
3rd, with gradual anterior descension, an elevated lamellar blade.
Palatal traces deeply recessed, located one below 1st palatal, one
between each pair of major palatals and three above the 5th palatal.
Height of holotype 2.54 mm., diameter 4.21 mm.
Holotype. — Austral Islands: Rapa Island. Station
346, hillside west of Mt. Tevaitahu at 750 ft. elevation.
Collected under stones in forest by Donald Anderson
on July 9, 1934. BPBM 142462.
Range. — Mt. Tevaitahu and Morongoto, Rapa
Island, Austral Islands.
Paratypes. — Same as list of material.
Material. — Rapa Island: hillside west of Mt.
Tevaitahu (Station 346) at 750 ft. elevation (31
specimens, BPBM 142462-7); hillside (Station 360) at
Morongoto (2 specimens, BPBM 144245).
Remarks. — Juvenile specimens of less than four
whorls had the prominent radial ribbing present on the
shell base. Subadult and adult examples had the base
essentially devoid of sculpture, quite smooth and
shining. Only six of the 31 specimens from Station 346
were adult and both of the Morongoto specimens were
juvenile.
The columellar barrier is larger than the palatal,
accessory ridges are present on the sides of the major
parietals, there is great reduction of the radial
sculpture, and a complete absence of radial sculpture
on the shell base. These features combine to make
Kondoconcha othnius the most distinctive species of
Endodontidae found on Rapa Island. Comparisons
with Orangia and Opanara are given above under the
generic discussions. The barrier structure is the same
seen in other Rapan genera, except for the large
number of accessory traces and the addition of these
laterally on the parietals.
The Hawaiian Endodonta binaria (Pfeiffer, 1856)
is strikingly similar in general appearance, having the
same shape and identical sculptural reduction on the
upper surface. Although obviously more depressed and
with a wider umbilicus than K. othnius (tables
LXXXI, XCVIII), the convergent nature of the
similarities in shape and sculpture is clearly revealed
by the widely different form of the barriers and
subperipheral sculpture. K. othnius has barriers identi-
cal to those seen in the Rapan taxa, essentially simple
in form and roundly expanded and serrated above; E.
binaria has the bifurcately expanded parietals and
palatals typical of Endodonta (fig. 167g). Kondo-
TABLE XCVIII. - LOCAL VARIATION IK ENDODONTA
Number of
Specimens Height
ekahanuiensls
Ekahanui, Waianae
FMNH 154483
H/D Ratio
D/U Ratio
2 1.4710.008 2.77*0.041 0.531±0.0410 43/4 3.48*0.160
(1.46-1.48) (2.73-2.81) (0.520-0.542) (3.32-3.64)
Aperture
FMNH 46567
concentrata
FMNH 46613.
FMNH 73192,
FMNH 90627
lamlnata
FMNH 46455
FMNH 117042
lamellosa
Oahu. FMNH 73199,
FMNH 91143,
FMNH 91839.
FMNH 154481
Mt. Konahuanui, Oahu,
FMNH 46275.
FMNH 116901
kamehameha
FMNH 73198.
FMNH 90629
marsuplalis
FMNH 116902
frlckl
Makalea, Waianae
FMNH 53042,
FMNH 111526
Miscellaneous exact
localities
2 1.92*0.083 4.26*0.149 0.452*0.0035 57/8* 3.46*0.110
(1.84-2.01) (411-4.41) (0.4480.455) (53/4-61/8) (3.35-3.57)
7 2-.38*0.051 5.06*0.086 0.471*0.0039 51/4- 4.90*0.147
(2.17-2.60) (4.70-5.43) (0.458-0.487) (5-51/2) (4.43-5.50)
6 2.55t0.043 6.22*0.069 0.411*0.0088 63/8 3.50*0.103
(2.472.70) (6.056.55) (0.377-0.436) (61/4-61/2) (3.12-3.84)
15 2.83*0.053 6.44*0.299 0.439*0.0051 6» 4.18*0.134
(2.503.09) (5.867.24) (0.402-0.472) (53/8-61/2) (3.18-5.10)
4 2.89*0.081 6.61*0.275 0.439*0.0062 57/8. 4.21*0.329
(2.703.09) (6.057.37) (0.4200.446) (53/8-65/8) (3.614.84)
4 3.13*0.043 6.91*0.194 0.453*0.0120 61/8- 3.42*0.106
(3.03-3.22) (6.387.30) (0.432-0.485) (57/8-63/8) (3.23-3.69)
2 3.45*0.231 7.20*0.186 0.480*0.0050 63/8 5.11*0.517
(3.22-3.68) (6.64-7.76) (0.475-0.435) (6 1/4-6 1/2) (4.59-5.62)
22 3.66*0.082 8.99*0.108 0.407*0.0056 61/2 3.60*0.049
(2.964.61) (8.03-9.67) (0:357-0.476) (6-7) (3.17-4.10)
14 a.55i0.070 8.99*0.166" 0.396*0.0080 61/2* 3.72*0.071
(3.09-3.82) (8.22-10.1) (0.329-0.437) (61/8-67/8) (3.32-4.17)
1 4*0-1
1 4.3-4-6
1 5*0-1-2
1 4*1-2
1 4*1-2-3
1. Summarized from Cooke (1928).
SYSTEMATIC REVIEW
371
concha othnius has essentially no subperipheral sculp-
ture on the body whorl; E. binaria has prominent
radial sculpture and very strong secondary spiral
cording. While neither has been dissected, the differ-
ences between Endodonta fricki and the Rapan genera
are marked and I have no doubt that the similarities
are convergent.
Genus Endodonta Albers, 1850
Die Heliceen, ed. 1, p. 89.
Endodontidae with typical apical sculpture, secondarily reduced
in concentrata, marsupialis, fricki, and lamellosa. Postnuclear
whorls rarely with wide, prominent radial ribs (ekahanuiensis),
reduced on body whorl (binaria) or lower spire (laminata), or (most
frequently) shell surface macroscopically smooth. Apex and spire
weakly (kamehameha) to moderately elevated, H/D ratio relatively
low, above 0.500 only in ekahanuiensis. Body whorl flattened above
and below a threadlike keel or knife-edge periphery (concentrata,
kamehameha, fricki). Whorls 57/8-6'/2, reduced only in concentrata
(5'4-) and ekahanuiensis (4%). Umbilicus widely open, U-shaped, last
whorl barely (concentrata, kamehameha), regularly (laminata), or
more rapidly decoiling, modified into brood pouch only in marsu-
pialis. Size slightly smaller than average (ekahanuiensis) to very
large (fricki). Parietal barriers 2, relatively long, generally weakly to
strongly bifid above, simple only in laminata and kamehameha.
Columellar barrier rather large, reaching lip margin (concentrata,
marsupialis) or midway across callus, lying parallel to plane of
coiling or slightly slanted downwards (marsupialis, ekahanuiensis).
Palatal barriers 4 or 5 (lamellosa. marsupialis), bifid only in binaria.
usually with one or two accessory traces (absent in kamehameha
and sometimes concentrata), generally four in laminata. Pallial
region typical endodontid, with short rectal kidney arm. Hermaphro-
ditic duct uncoiled. Talon with small, globular head and tapered
shaft. Uterus bipartite. Vas deferens entering penis subapically.
Latter of variable length, internally with two longitudinal pilasters
of varying size that combine or fade out near atrium. Spermathecal
shaft joining free oviduct at or just above rather elongated atrium.
Penial retractor originating from columellar muscle above buccal
retractor origin, inserting directly onto head of generally rather long
penis. Jaw of partly fused, very narrow lamellar plates, which are
individually wider than in Cookeconcha, but are still too indistinct
for accurate counting. Radula typical in structure.
Type species. — Helix lamellosa Ferussac, 1824 (by
subsequent designation of von Martens, 1860, p. 90).
The carinated periphery, marked tendency toward
reduction of shell sculpture, generally bifid upper
parietal barrier, and U-shaped, rather flat-sided umbil-
icus are distinctive shell features of Endodonta. Of the
other Hawaiian genera, Nesophila is distinguished by
its large size, absence of any columellar or palatal
barriers, and splitting of the parietals into seven to
eleven threadlike traces; Cookeconcha by its generally
rounded or laterally compressed periphery (except
stellulus], retention of marked radial ribbing, and
marked tendency toward loss of palatal and columellar
barriers. That Endodonta is a derivative of Cook-
econcha-type ancestors is made reasonably certain by
the presence of bifid upper parietals in the C.
henshawi complex and a general tendency for loss of
the apical sculpture in Cookeconcha. These character-
istics are not seen in other Pacific Island Endodon-
tidae and I have no doubt that Cookeconcha,
Nesophila, and Endodonta form a monophyletic
group.
Similarities between Endodonta and extralimital
genera are gross and recognizable as parallel or
convergent in nature. The Society Islands genus
Nesodiscus has a similar tendency toward loss of
sculpture, but the widely open umbilicus is cup-
shaped, regularly decoiling, and occasionally serves as
a brood chamber through secretion of a mucus
membrane across the opening. The character of the
keeling is quite different in Nesodiscus; the parietal
barriers are not bifid; and the palatal barriers are
much different in shape and very deeply recessed.
Nesodiscus is a derivative of Mautodontha, with M.
boraborensis relatively intermediate in structure. The
Rapan Kondoconcha othnius is strikingly similar to
Endodonta binaria in form, barrier count, and
sculpture, but even casual inspection of the apertural
barriers in the two species shows very different
structure and shape.
The treatment below is not intended as a formal
revision of Endodonta. It is based only on material in
the Field Museum of Natural History collection and
attempts to provide an indication of variational
patterns within this material. Previously recorded
knowledge was not sufficient to allow an assessment of
how Endodonta was related to Polynesian genera.
Hence this brief survey was necessary in order to place
Endodonta within the family. Slightly more than 2,100
sets of Endodonta, containing at least 25,000 speci-
mens, are preserved in the Bernice P. Bishop Museum.
Particularly in regard to the forms from the Waianae
Mountains, there is a bewildering amount of variation,
both intra- and supraspecific, that offers a magnificent
opportunity for the study of microevolution. An
accurate guess as to the actual number of species in
Endodonta is impossible. On the basis of Cooke's
sorting, about 78 species and an additional 55
geographic races have been segregated (table II).
Eventual recognition of at least 100 species-level taxa
will be necessary.
A full diagnosis for each species is given where
material was available. No examples of E. apiculata
Ancey, 1889 and E. rugata (Pease, 1866) were seen.
Literature references to these species are included for
completeness. Under each species, some comparative
remarks are made, primarily concerned with advanced
versus primitive characters. Since only a small fraction
of existing (or recently extinct) species are covered
below, no formal comparisons or keys have been
constructed. To avoid giving an erroneous impression
of size and sculpture range in Endodonta, description
of a single new species, E. ekahanuiensis, is included.
Three species, E. lamellosa, E. fricki, and E.
marsupialis, have been dissected. Differences of sys-
tematic importance are few, primarily concerning penis
length, pilaster size and shape, plus the point of vas
deferens insertion. The penial, oviducal, and vas
deferens ceilings cited by Cooke (1928, pp. 22, 23, 26)
are artifacts caused by withdrawal of the animal into
MC
TV
MG
FlG. 163. Anatomy of Endodonta fricki. Waianae Mts., Oahu, Hawaii. BPBM 128063: a, Head and foot from left side, rhinophores fully
retracted; b, detail of mantle collar in undissected specimen; c, apex of visceral mass showing relationship of ovotestis (G), digestive gland (Z),
and intestine (I); d, relative position of organs at apex of pallia! cavity, systems slightly separated; e, pallia! region flattened and pinned out.
(See Appendix for explanation of abbreviations.)
372
FlG. 164. Anatomy of Endodonta fricki. Waianae Mts., Oahu, Hawaii. BPBM 128063: a, genital system dissected out and uncoiled; b, detail
of apical genitalia; c, interior of penis showing pilasters (PP) and opening of vas deferens (DP); d, organization of prostate-uterus; e, buccal
mass and esophagus from right side; f, ventral view of stomach and loops of intestine prior to hindgut. (See Appendix for explanation of
abbreviations.)
373
GG
FlG. 165. Anatomy of: a-b, Endadonta lamellosa (Ferussac). Koolau Mts., Oahu. BPBM 16556. a, genitalia, b, interior of penis; c-g,
Nesophila tiara (Mighels). Wailua, Kauai. BPBM 81310. c, pallial region, d, genitalia, e, structure of ovotestis clump, /, form of talon and
juncture with carrefour, g, interior of penis; h-i, Cookeconchajugosus (Mighels). Wailua, Kauai. BPBM 81197. h, genitalia; i, interior of penis; j-
k, Cookeconcha hystricellus (Pfeiffer). Popowela, Waianae Mts., Oahu. BPBM 35421. j, genitalia, k, interior of penis. Scale lines equal 1 mm.
374
SYSTEMATIC REVIEW
375
the shell. E. lamellosa has a short penis, 4.4-6.1 mm.
long, with the vas deferens inserting well below the
apex and the pilasters are thick and very large
apically; E. marsupialis has a very large penis, 12-15
mm. long, with the vas deferens entering far (3.5 mm.)
below the penis head; and E. fricki has a penis 9-10
mm. long, with the vas deferens inserting almost
directly below the penis head and the pilasters much
smaller and lower than in E. lamellosa (fig. 165a-b).
Dissections of specimens from different populations in
the Waianae Mountains might reveal a situation
similar to that found in the Arizona-New Mexico
Sonorella, where penial size is correlated with dryness
of habitat. The many populations of E. fricki were
ideally suited for undertaking such an investigation.
Endodonta ekahanuiensis, new species. Figure
166a-c.
Diagnosis. — Shell Very small, diameter 2.73-2.81 mm. (mean
2.77 mm.), with 4'4 normally coiled whorls. Apex and spire
moderately strongly elevated, rounded above, last whorl not
descending more rapidly. H/D ratio 0.520-0.542 (mean 0.531).
Umbilicus widely open, U-shaped, early whorls not decoiling, last
whorl decoiling more rapidly, contained 3.32-3.64 times (mean 3.48)
in the diameter. Apical whorl with prominent radial ribs and typical
microribbing. Postnuclear whorls with broad, rounded, protractively
sinuated radial ribs. 37-45 (mean 41) on the body whorl, whose
interstices are less than twice their width. Microsculpture of fine
radial riblets, three to five between each pair of major ribs, crossed
by much finer and more crowded spiral riblets, with a secondary
sculpture of broad, low spiral cords present below periphery. Sutures
shallow, whorls flatly rounded down to supraperipheral sulcus. Keel
threadlike, protruded, lower palatal margin evenly rounded, basal
margin more strongly rounded to obtusely rounded umbilical margin.
Walls of umbilicus flatly rounded, retaining sculpture to apex.
Aperture flatly rounded above and below protruded threadlike
periphery, inclined about 15° from shell axis. Parietal barriers 2,
extending posteriorly one-quarter whorl: upper high and slender.
with sharp anterior descension, becoming twisted upward posteriorly
with a broadly expanded bifid lateral portion on posterior two-thirds,
separation of main and bifid sections very indistinct to appearing
deflected downwards: 2nd slightly lower posteriorly, broadly ex-
panded above, with gradual descension to broadly threadlike anterior
third that terminates slightly in front of upper parietal. Columellar
barrier a high lamellar blade, broadly expanded and serrated above
posteriorly, slightly twisted downwards from plane of coiling, with
gradual anterior descension midway across columellar callus. Palatal
barriers 4, extending posteriorly slightly more than one-eighth whorl,
slightly recessed, with one supraperipheral accessory trace just below
4th palatal: lower 3 high and bladelike, with progressively more
gradual anterior descension and with 1st and 3rd slightly smaller
than 2nd. all broadly expanded above: 4th supraperipheral, longer,
lower, less deeply recessed, with very gradual anterior descension.
Palatal trace very deeply recessed, about half height of 4th palatal.
The very small size, retention of strong radial
ribbing on the body whorl, very high spire, and broadly
expanded palatal barriers separate Endodonta ekaha-
nuiensis from the other described species. In having
secondary spiral sculpture on the shell base, it
resembles the Kauai Island E. binaria and E.
laminata, both of which are much, much larger (mean
diameters 4.26 and 6.22 mm., respectively), lack major
ribs on the body whorl, and have two to six palatal
traces. The protruded keel at once separates E.
ekahanuiensis from all described Cookeconcha.
FIG. 166. a-c, Endodonta ekahanuiensis, new species. Holotype.
FMNH 154483. Station W410C-6, Waianae Mts., Oahu, Hawaiian
Islands. Scale line equals 1 mm. (MM).
376
SOLEM: ENDODONTOID LAND SNAILS
Description. - Shell very small, with slightly less than 4*4
normally coiled whorls. Apex and spire moderately elevated, rounded
above, last whorl not descending more rapidly, H/D ratio 0.520.
Apical whorls l'/2, sculpture partly eroded, visible in sutures as
prominent, rather widely spaced radial ribs, broadly rounded, with
one or two microradials in between and vague traces of microspiral
ribbing. Postnuclear whorls with major and microribbing as in
diagnosis, body whorl with 37 major ribs. Secondary spiral cording
starting distinctly below periphery and stopping well before umbilical
margin. Sutures shallow, whorls flatly rounded down to prominent
supraperipheral sulcus. Keel threadlike, protruded, lower palatal wall
evenly rounded down to obtusely rounded umbilical margin. Ground
color leached from shell, lower spire, and body whorl with irregularly
broad, dark reddish f lammulations that become narrow and
zigzagged on shell base. Umbilicus widely open. U-shaped, barely
decoiling until last whorl, which decoils much more rapidly,
contained 3.64 times in the diameter. Aperture subquadrangular,
flatly rounded above and below rostrate periphery, inclined about
15° from shell axis. Apertural barriers as described in "Diagnosis"
above. Height of holotype 1.46 mm., diameter 2.81 mm.
Holotype. - Loc. 3 (= W410C-6), north branch,
south Ekahanui Gulch, Waianae Mountains, Oahu,
Hawaiian Islands. FMNH 154483.
Range. — Known only from the type collection.
Paratype. - FMNH 154605.
Material. — Hawaiian Islands: Oahu, Waianae
Mountains, north branch, south Ekahanui Gulch (2
specimens, FMNH 154483, FMNH 154605). Additional
type lot material is BPBM 125254.
Remarks. — I had not intended to describe any
Hawaiian taxa in this study, but naming of this species
was necessary in order to avoid overemphasizing the
differences between Cookeconcha and Endodonta.
Without E. ekahanuiensis, Endodonta would have
appeared as being separated in both size (compare
tables LXXIV and XCVIII) and ribbing character;
with E. ekahanuiensis included, the differences are
bridged and recognition of Endodonta as a specialized
offshoot from Cookeconcha-type ancestors becomes
much easier.
The extent of this species' range on Oahu is
unknown. A map showing the exact position of the
type locality is given by Welch (1938, p. 105, map 13).
Endodonta binaria (Pfeiffer, 1856)
Helix binaria Pfeiffer, 1856, Proc. Zool. Soc. London, 1856, p. 33 -
Sandwich Islands; Pfeiffer, 1859. Mon. helic. viv., 4. p. 156;
Pfeiffer, 1868, Mon. helic. viv., 5, p. 222; Pfeiffer, 1876, Mon.
helic. viv., 7, p. 260; Tryon, 1887, Man. Conchol., (2), 3, p. 61, pi.
11, figs. 87, 88.
Endodonta binaria (Pfeiffer), Pease, 1871, Proc. Zool. Soc.
London, 1871, p. 474 - Kauai; Ancey, 1889, Bull. Soc. Malacol.
France, 6, p. 189; Pilsbry, 1893, Man. Conchol., (2), 9, p. 25.
Patula (Endodonta) binaria (Pfeiffer), Clessin, 1881, Nomen. Helic.
viv.. p. 95.
Helix (Endodonta) binaria Pfeiffer, Baldwin, 1893, Catalogue
Land and Fresh Water Shells, p. 16 - Kauai.
Endodonta (Nesophila) binaria (Pfeiffer), Sykes, 1900, Fauna
Hawaiiensis, Moll.. 2. (4), p. 289.
Diagnosis. - Shell small, diameter 4.11-4.41 mm. (mean 4.26
mm.), with 53/4-6Mi normally coiled whorls. Apex and spire moderately
and almost evenly elevated, somewhat rounded above, last whorl not
descending more rapidly, H/D ratio 0.448-0.459 (mean 0.452).
Umbilicus widely open, U-shaped, last whorl decoiling much more
rapidly, contained 3.35-3.57 times (mean 3.46) in the diameter. Apical
sculpture of major radials and fine microradials and spirals.
Postnuclear whorls with thick, prominent radial ribs at first,
becoming broadly rounded and somewhat indistinct after first
postnuclear whorl, fading into irregular ridges well before start of
body whorl, but retained on shell base and in umbilicus as relatively
prominent ribs. Microsculpture of fine radial riblets, crossed by spiral
riblets that are less than half the size of the radials and much more
crowded. Secondary sculpture of several low, rounded spiral cords
developed on shell base, but absent from above periphery. Sutures
very shallow, whorls flatly rounded down to shallow supraperipheral
sulcus. Strongly protruded threadlike keel followed by evenly
rounded, compressed lower palatal margin that curves slightly more
rapidly to right-angled umbilical shoulder. Walls of umbilicus
distinctly flattened. Aperture subquadrangular, flattened laterally
above and below rostrate periphery, inclined about 25° from shell
axis. Parietal barriers 2, extending posteriorly to line of vision: upper
very slender and sharply descending anteriorly, twisted upward and
outward posteriorly with a broadly expanded lateral bifid section
posteriorly; 2nd equal in size and shape to 1st posteriorly, anterior
three-eighths a threadlike trace reaching to margin of upper parietal.
Columellar barrier high and bladelike, expanded and serrated
above posteriorly, parallel to plane of coiling, extending midway
across columellar callus. Palatal barriers 4, extending posteriorly to
line of vision, first 3 sub-, 4th supraperipheral, with two accessory
traces: all palatals bifid posteriorly, 3rd and 4th lower than first 2.
with gradual anterior descension, moderately recessed within
aperture. Accessory traces high, threadlike ridges, both between 3rd
and 4th palatals, one sub- and the other supraperipheral. Upper
parietal and upper palatal nearly touching on elevated portions.
Range. — Kauai, Hawaiian Islands.
Material. — Hawaiian Islands (2 specimens,
FMNH 46567 ex Webb, Geret).
Remarks. — Pfeiffer's original description over-
looked the palatal barriers, hence Sykes (1900, p. 289)
referred E. binaria to Nesophila. The smaller size and
presence of two accessory palatal traces are the main
features separating E. binaria from the description of
E. apiculata. Study of the abundant Kauai material in
the Bernice P. Bishop Museum will be required to
determine their relationships.
In retaining rather widely spaced, low, and
rounded major radial ribs on the shell spire and base,
E. binaria departs from the pattern found in most
Endodonta. The sculpture is very similar to that
found in Kondoconcha othnius from Rapa, but the
similarities are convergent. The extreme broadening
and flattening of the barriers in E. binaria also is
unusual. Many taxa have bifid parietals, but E.
binaria is the only species known to date with bifid
palatals.
Endodonta apiculata Ancey, 1889
Endodonta apiculata Ancey, 1889, Bull. Soc. Malacol. France, 6,
pp. 188-189 - Kauai, Hawaiian Islands; Pilsbry, 1892, Man.
Conchol., (2), 8, p. 95; Pilsbry, 1893, op. cit., (2), 9, p. 25; Sykes,
1900, Fauna Hawaiiensis, Moll., 2, (4), p. 287.
Helix (Endodonta) apiculata (Ancey). Baldwin, 1893, Catalogue
Land and Fresh Water Shells, p. 16.
Range. — Kauai, Hawaiian Islands.
Material. — No specimens examined.
SYSTEMATIC REVIEW
377
Remarks. — The retention of some radial sculp-
ture on the spire and presence of spiral sculpture on
the shell base relate this to E. binaria, also described
from Kauai. Endodonta apiculata differs in being
distinctly larger (diameter 6 mm.), having more whorls
(6'/2) and lacking (?) any accessory traces on the
palatal wall.
Endodonta rugata (Pease, 1866)
Helix rugata Pease, 1866. Amer. Jour. Conchol., 2, p. 291 -
Sandwich Islands; Pfeiffer, 1876, Mon. helic. viv., 7, p. 256;
Tryon, 1887, Man. Conchol., (2), 3, p. 67.
Endodonta rugata (Pease), Pease, 1871, Proc. Zool. Soc. London.
1871, p. 474 - Maui, Hawaiian Islands; Ancey. 1889, Bull. Soc.
Malac. France, 6, p. 187; Pilsbry, 1893, Man. Conchol., (2), 9, p.
25.
Patula (Endodonta) rugata (Pease), Clessin, 1881. Nomen. helic.
viv., p. 96.
Helix (Endodonta) rugata Pease, Baldwin. 1893, Catalogue Land
and Fresh Water Shells, p. 16.
Endodonta (Thaumatodon) rugata (Pease), Sykes, 1900, Fauna
Hawaiiensis, Moll., 2, (4), p. 289.
Range. — Maui, Hawaiian Islands.
Material. — None.
Remarks. — The carinated body whorl, wide
umbilicus, large size (5 mm. diameter), and presence of
secondary spiral sculpture suggest that E. rugata is a
relative of E. binaria and E. apiculata.
Endodonta laminata (Pease, 1866)
Helix laminata Pease, 1866, Amer. Jour. Conchol., 2. p. 292 -
Sandwich Islands; Pfeiffer, 1876, Mon. helic. viv., 7, p. 255.
Endodonta laminata (Pease), Pease, 1871, Proc. Zool. Soc.
London, 1871, p. 474 - Kauai, Hawaiian Islands; Ancey, 1889,
Bull. Soc. Malacol. France, 6, p. 188; Pilsbry, 1893, Man.
Conchol., (2), 9, p. 25; Sykes, 1900, Fauna Hawaiiensis, Moll., 2,
(4), p. 287 — Kahiliwi to Haena, Kauai, Hawaiian Islands;
Cockerell, 1925, Nautilus. 38, (3), p. 83 - Haena Caves, Kauai.
Patula (Endodonta) laminata (Pease), Clessin, 1881, Nomen. helic.
viv., p. 96.
Helix (Endodonta) laminata Pease, Baldwin, 1893, Catalogue
Land and Fresh Water Shells, p. 16 — Kalihawai to Haena,
Kauai.
Diagnosis. — Shell slightly larger than average, diameter 6.05-
6.55 mm. (mean 6.22 mm.), with 6'4-6'/2 normally coiled whorls. Apex
and spire moderately and evenly elevated, rarely slightly rounded
above, last whorl not decoiling more rapidly, H/D ratio 0.377-0.436
(mean 0.411). Umbilicus widely open, U-shaped, regularly decoiling,
contained 3.12-3.84 times (mean 3.50) in the diameter. Apical
sculpture of low, rather broad, widely spaced radial ribs with typical
microsculpture between, continuing onto first postnuclear whorls,
fading into indistinct irregularity by antepenultimate whorl, absent
from lower spire and body whorl which retains irregular traces of
very fine microradial and slightly finer microspiral ribbing. Secon-
dary sculpture of broad, low spiral cords present between subpe-
ripheral sulcus and umbilical shoulder. Sutures shallow, whorls flatly
rounded down to shallow supraperipheral sulcus. Threadlike keel
strongly protruded, followed by very shallow subperipheral sulcus,
lower palatal wall flattened, basal margin evenly rounded to
obtusely angled umbilical margin. Walls of umbilicus flatly rounded.
Aperture subquadrangular, flattened laterally above and below
strongly protruded periphery, inclined about 35° from shell axis.
Parietal barriers 2, extending posteriorly less than one-quarter whorl:
upper very high and thin with sharp anterior descension, twisted
outward posteriorly but neither bifid nor strongly expanded; 2nd
distinctly low ;r posteriorly, anterior third threadlike, terminating
opposite end of upper parietal. Columellar barrier high and bladelike,
weakly expanded above, with gradual anterior descension, extending
midway across columellar callus, lying parallel to plane of coiling.
Palatal barriers 4, lower extending less than one-eighth whorl
posteriorly, with three to six accessory traces: lower 3 high and
crescentic, progressively reduced in height, moderately recessed, with
sharp anterior descension; 4th supraperipheral, much longer, with
more gradual anterior descension, less deeply recessed within
aperture. Traces normally between columellar and 1st palatal; 1st
and 2nd; with two between 3rd and 4th. Additional traces may be
between 2nd and 3rd, above 4th palatal.
Range. — Kahiliwi to Haena, Kauai, Hawaiian
Islands.
Material. — Hawaiian Islands: Kauai (6 speci-
mens, FMNH 46455, FMNH 117042).
Remarks. - Ancey (1904, p. 66, pi. 5, figs. 13, 14)
reported an unknown species of Cookeconcha from
Palihoukapapa, Hamakua slope of Mauna Kea, at
4,000 ft. elevation, Hawaii as Endodonta laminata.
Probably it is a new species.
The widely open, V-shaped umbilicus with
roundly shouldered margin, low spire, presence of
weak, reduced major radials on the upper spire, and
irregularly spaced spiral sculpture on the shell base
serve both to identify E. laminata and relate it to the
other Kauai taxa.
The upper parietal barrier is weakly bifid, and the
upper palatal has its tip turned outward toward the
periphery. All other barriers are simple crescents.
Accessory palatal traces normally are between the
columellar and 1st palatal; between 1st and 2nd
palatals; above 3rd and below periphery; below 4th
and above periphery. Additional traces are sometimes
present between 2nd and 3rd palatal or above 4th
palatal.
There is a weak supraperipheral sulcus.
Endodonta kamehameha Pilsbry & Vanatta,
1906. Figure 167c-d.
Endodonta kamehameha Pilsbry & Vanatta, 1906, Proc. Acad.
Nat. Sci., Philadelphia, 57, pp. 784-785, pi. 43, figs. 3, 4 - Wailau
Pali, Mapulehu, Molokai, Hawaiian Islands.
Diagnosis. — Shell large, diameter 6.38-7.30 mm. (mean 6.91
mm.), with 5%-6% normally coiled whorls. Apex and spire very
slightly and evenly elevated, last whorl decoiling slightly more
rapidly, H/D ratio 0.432-0.485 (mean 0.453). Umbilicus open, U-
shaped, slightly and regularly decoiling, contained 3.23-3.69 times
(mean 3.42) in the diameter. Apical sculpture unknown, postnuclear
whorls macroscopically smooth, with only irregular growth striae
visible under high magnification. Sutures very shallow, whorls flat
down to shallow supraperipheral sulcus. Knife-edge keel sharply
protruded, whorls flatly rounded down to obtusely angled umbilical
margin. Walls of umbilicus flatly rounded. Aperture subquadrangu-
lar, flattened above and below protruded knife-edge periphery,
inclined about 20° from shell axis. Parietal barriers 2, extending
posteriorly three-sixteenths of a whorl: upper a high, thin blade,
weakly expanded above on posterior half, descending abruptly to
anterior third that is a low ridge; 2nd a broad, low, rounded ridge
posteriorly, anterior half to five-eighths threadlike, terminating
opposite end of upper parietal. Columellar barrier low and bladelike,
weakly elevated above, lying parallel to plane of coiling, with
gradual anterior descension to middle of columellar callus. Palatal
378
SOLEM: ENDODONTOID LAND SNAILS
barriers normally 4, supraperipheral often absent, rest relatively low
and short, extending posteriorly about one-eighth whorl: lower 3
subperipheral, moderately recessed, low ridges not or weakly
expanded above, 1st slightly smaller than 2nd and 3rd; 4th
supraperipheral, when present, a very low ridge to threadlike trace,
longer than lower palatals and not so deeply recessed.
Range. — Molokai, Hawaiian Islands.
Material. — Hawaiian Islands: Molokai, Wailau (3
specimens, FMNH 73198), Kamalo (1 specimen,
FMNH 90629).
Remarks. — The widely open, narrowly U-shaped,
regularly decoiling umbilicus, colorless shell, and great
size reduction of all apertural barriers, with the upper
parietal being a simple lamella rather than bifid, easily
separate Endodonta kamehameha from the other
described species.
There is no major radial sculpture, a barely
perceptible supraperipheral sulcus and the umbilical
walls are flat sided, but the umbilical margin is less
sharply angled than in the Oahu species.
All other described Endodonta have the upper
parietal bifid. I suspect its simplicity in E. kameha-
meha is correlated with the secondary size reduction of
all apertural barriers. One specimen had the upper
palatal absent.
Endodonta concentrata Pilsbry & Vanatta,
1906. Figure 167e-f.
Endodonta concentrata Pilsbry & Vanatta, 1906, Proc. Acad. Nat.
Sci., Philadelphia, 57, p. 785, pi. 43, figs. 5, 6 - Lanai, Hawaiian
Islands.
Diagnosis. — Shell rather small, diameter 4.70-5.43 mm. (mean
5.06 mm.), with 5-5'/2 normally coiled whorls. Apex and spire
moderately and evenly elevated, slightly rounded above, last whorl
descending a little more rapidly, H/D ratio 0.458-0.487 (mean 0.471).
Umbilicus rather narrow, U-shaped, early whorls barely decoiling,
penultimate whorl narrowing slightly, body whorl decoiling a little
more rapidly, contained 4.43-5.50 times (mean 4.90) in the diameter.
Apical whorls and postnuclear whorls [microscopically smooth, lower
spire with irregular growth wrinkles and occasional vague indications
of a microreticulation visible under 96 X magnification. Sutures not
indented, whorls flat down to protruded knife-edge keel, compressed
and flatly rounded to basal margin, then more sharply rounded to
obtusely angled umbilical margin. Sides of umbilicus flattened.
Aperture subquadrangular, flattened laterally above and below
acutely angled periphery, inclined almost 45° from shell axis.
Parietal barriers 2, extending posteriorly one-quarter whorl: upper
very high and thin anteriorly with sharp descension, becoming
broadly bifid and serrated above posteriorly; 2nd slightly lower,
broadly expanded but not bifid posteriorly and gradually descending
from middle to anterior end, which is even with termination of upper
parietal. Columellar barrier high, broadly expanded and serrated
above posteriorly, lying parallel to plane of coiling, sharply
descending anteriorly to lip margin. Palatal barriers 4, extending
three-sixteenths of a whorl posteriorly, with or without a single large
recessed accessory subperipheral trace located above 3rd palatal:
lower 3 coequal in height, broadly expanded above, subperipheral.
with progressively more gradual anterior descension and deeper
recession; 4th supraperipheral. lower, longer, with very gradual
anterior descension. moderately expanded above. Palatal trace, when
present, about one-third height and length of major barriers, only
weakly expanded above.
Range. — Lanai, Hawaiian Islands.
Material. — Hawaiian Islands: Lanai (3 specimens,
FMNH 73192, FMNH 90627), Lanaikale (4 specimens,
FMNH 46613).
Remarks. — As in Endodonta marsupialis, the
comparatively high spire and narrow umbilicus of E.
concentrata are correlated and related to formation of
a "brood chamber." In E. concentrata, however, there
is little or no indication of actual umbilical narrowing
and no trace of the sinus extension that characterizes
E. marsupialis. The umbilical narrowing in E. con-
centrata has been achieved by a tightening of coiling
and thus a cessation of widening from the third whorl.
In form, the umbilicus is a perfect U-shaped, with
sharply rounded margins.
The low mean whorl count, more than a half
whorl less than in any other Endodonta, and small
size combine with the above two characters to identify
this species.
The apertural barriers are typical, with the upper
parietal distinctly bifid, but the remaining barriers
simple. The accessory palatal trace, which may be
present or absent, is always between the 3rd palatal
and the periphery.
There is no trace of major radial postnuclear
sculpture and no supraperipheral sulcus.
Endodonta lamellosa (Ferussac, 1824). Figure
165a-b.
Helix (Helicodonta) lamellosa Ferussac, 1821, Tab. Syst. Animales
Moll.. Part 2, p. 34 - Islands of South Seas (nomen nudum);
Ferussac, in Quoy & Gaimard, 1824, Voy. "Uranie"... Freycinet,
Zool., p. 469; Ferussac, 1832, Hist. Nat. Moll. terr. fluv., 3, pi.
51a, fig. 3.
Helix lamellosa Ferussac, Pfeiffer. 1848. Mon. helic. viv., 1. pp.
184-185 (partly I - Wahoo (= Oahu. Hawaiian Islands);
Deshayes, 1851, Hist. Nat. Moll. terr. fluv., 1, p. 369 (French not
Latin description) — Sandwich Islands; Pfeiffer, 1853, Mon.
helic. viv., 3, p. 142 (partly); Reeve, 1854, Conchol., Icon., Helix,
pi. Ill, fig. 630 - Sandwich Islands; Pfeiffer, 1859, Mon. Helic.
viv., 4, p. 154; Pfeiffer, 1868, Mon. helic. viv., 5, p. 219; Pease,
1871. Jour, de Conchyl., 19. p. 96 (partly) - Oahu, Hawaiian
Islands; Pfeiffer. 1876. Mon. helic. viv.. 7, p. 255.
Endodonta lamellosa (Ferussac). Albers, 1850, Die Heliceen, p. 89;
Morch, 1865, Jour, de Conchyl., 13, pp. 395-396; Pease, 1871,
Proc. Zool. Soc., London. 1871, p. 474 - Oahu (partly); Ancey,
1889, Bull. Soc. Malacol. France, 6, p. 186 (partly); Sykes, 1900,
Fauna Hawaiiensis, Moll., 2, (4), p. 287 — Konahuanui, Oahu
(partly); Cooke. 1928. Bull. B. P. Bishop Museum, 47, pp. 14-21,
figs. 3. 4. 5 (anatomy).
Pitys lamellosa H. & A. Adams, 18.58, Genera Recent Moll., 2, p.
113 and 3, p. 71, fig. 5.
Patula (Endodonta) lamellosa Clessin, 1881. Nomen. helic. viv., p.
96 (partly).
Helix (Endodonta) lamellosa Ferussac. Baldwin, 1893, Catalogue
Land and Fresh Water Shells, p. 16 - Waianae Mts. (error) and
Konahuanui. Oahu. Hawaiian Islands.
Diagnosis. — Shell distinctly larger than average, diameter 5.86-
7.37 mm. (mean 6.61 mm.), with 5:1/8-6V8 normally coiled whorls. Apex
and spire moderately and evenly elevated, last whorl not descending
more rapidly. H/D ratio 0.402-0.472 (mean 0.439). Umbilicus rather
narrow, U-shaped, barely decoiling at first, slightly narrowed at
penultimate whorl, last whorl decoiling rather rapidly, contained
3.18-5.10 times (mean 4.21) in the diameter. Apical and postnuclear
SYSTEMATIC REVIEW
379
FIG. 167. a-b, Endodonta marsupialis Pilsbry & Vanatta. Oahu, Hawaiian Islands. Holotype. ANSP 58190; c-d, Endodonta kamehameha
Pilsbry & Vanatta. Wailau Pali, Mapulehu, Molokai. Hawaiian Islands. Holotype. ANSP 90140; e-f, Endodonta concentrate! Pilsbry & Vanatta.
Lanai, Hawaiian Islands. Holotype. ANSP 89241; g-h, Endodonta fricki (Pfeiffer). "Kauai" (error for Waianae Mts., Oahu), Hawaiian Islands.
ANSP. Copied from Pilsbry and Vanatta (1906, pi. 43) with permission of the Academy of Natural Sciences, Philadelphia. Relabelled for this
whorls macroscopically smooth, rarely with faint traces of micro-
reticulations, often with faint and irregular growth lines. Sutures
shallow, whorls flatly rounded down to moderate supraperipheral
sulcus. Keel threadlike, strongly protruded, a shallower subperipheral
sulcus, lower palatal wall compressed, evenly rounded down to right
angled umbilical margin. Walls of umbilicus flat to slightly concave,
last two whorls with a distinct keel. Aperture subquadrangular,
flattened above, evenly rounded below strongly protruded threadlike
keel, inclined about 35° from shell axis. Parietal barriers 2. extending
posteriorly about three-sixteenths of a whorl: upper with sharp
anterior descension, high and thin, twisted upwards and much
elevated posteriorly with a broadly expanded and serrated bifid
lateral extension on posterior half; 2nd with posterior third elevated,
about two-thirds height of upper, moderately expanded above,
anterior half threadlike, recessed or terminating opposite end of
upper parietal. Columellar barrier high and bladelike, moderately
expanded above posteriorly, with gradual anterior descension
midway across callus, lying parallel to plane of coiling. Palatal
barriers 5, extending posteriorly one-eighth whorl, almost always
with two accessory traces: lower palatal high, weakly expanded
380
SOLEM: ENDODONTOID LAND SNAILS
above, only slightly recessed, with gradual anterior descension; 2nd,
3rd, and 4th progressively reduced in height, more deeply recessed,
with more gradual anterior descension; 5th supraperipheral, equal in
height to 4th posteriorly, much longer, with very gradual anterior
descension, less deeply recessed within aperture. Accessory traces,
small, crescentic, rather deeply recessed, situated between 4th and
5th palatals, one sub-, the other supraperipheral.
Range. — Mt. Konahuanui and Mt. Puu Ka-
huauli, Koolau Mts., Oahu, Hawaiian Islands.
Material. -- Hawaiian Islands: Oahu (15 speci-
mens, FMNH 73199, FMNH 91143, FMNH 91839,
FMNH 154481), Mt. Konahuanui (4 specimens,
FMNH 46275).
Remarks. — The identification of Helix lamellosa
Ferussac, 1824 by Cooke (1928, pp. 14 -19) is
an elegant example of historical and biological in-
vestigation. The somewhat more detailed synonymy
given above was possible only because of Cooke's
efforts.
A more open umbilicus that markedly decoils on
the last whorl, lower whorl count, smaller size, and
distinctly lower spire easily separate E. lamellosa from
the other Koolau species, E. marsupialis. E. fricki
from the Waianae Range is much larger (mean
diameter 8.99 mm.), with a lower spire, more widely
open umbilicus, has only 4 major palatal barriers, and
averages one-half whorl more than E. lamellosa (table
XCVIII).
As in all the large Oahu species, E. lamellosa has
no postnuclear major radial sculpture, the sides of the
U-shaped umbilicus are flat and the umbilical margin
sharply angled. The marked umbilical decoiling of the
last whorl is shared with E. fricki (fig. 167h), but is not
duplicated by any other Hawaiian species that has
been named. There is no supraperipheral sulcus.
The upper parietal barrier is bifid, but the others
are neither expanded nor twisted. Cooke (1928, p. 17)
summarized barrier variation in 97 specimens from Mt.
Konahuanui. One example had a 2nd columellar. All
specimens had 5 major palatals, 4 subperipheral ( =
basal in Cooke's terminology), and 1 supraperipheral
(erroneously referred to as "upper parietal" by Cooke,
an obvious lapsus calami). All specimens had the
supraperipheral accessory trace present and 75.8 per
cent (72 of 95) had the subperipheral accessory trace
present. The parietals extend less than three-six-
teenths of a whorl, the palatals less than one-eighth
whorl.
My dissections agree with those of Cooke (loc.
cit.). The penis is much shorter than in either E. fricki
or E. marsupialis, although variable in length. Cooke
(1928, p. 19) measured three penes as 4.4, 5.3, and 6.1
mm. long, a normal range of variation within the
family. My examples were 4.5-5.6 mm. long. No
complete specimens were available to me and the
attached anatomical description is based upon frag-
mentary examples.
Obvious differences from E. fricki involve the
prostate with its much greater number of acini and the
smaller penis with proportionately much larger pilas-
ters.
Description of soft parts. — Foot and tail as in E. fricki,
relatively short. Sole undivided. Pedal grooves typical, no caudal
horn or middorsal groove. Slime network inconspicuous. Head
projecting slightly in front of foot. Ommatophores with black
eyespot. Gonopore as in E. fricki.
Body color yellow-white, without darker markings.
Mantle collar and glandular extension as in E. fricki.
Pallial region with anterior portion as in E. fricki, no specimens
with basal portions seen. Lung roof clear, no granulations. Hindgut
typical.
Ovotestis and hermaphroditic duct not seen. Albumen gland (fig.
165a) very small compared to prostate. Talon not seen. Prostate
(DG) of several rows large acini opening into a small tube appressed
to surface of uterus, individual acini and rows much more numerous
than in E. fricki. Uterus (UT) bipartite, better preserved specimens
with faint indications of accessory glandular patches seen in
Thaumatodon, extending below base of prostate.
Vas deferens (VD) typical, recurved at penioviducal angle,
entering penis laterally, about 0.67-1.0 mm. below apex, underneath
edge of one pilaster. Penial retractor (PR) arising from columellar
muscle just above origin of buccal retractor, inserting onto
unexpanded head of penis. Penis (P) tapered anteriorly, rather
broadly expanded just below apex, about 4.5-5.6 mm. long, very
narrow at junction with atrium. Penis internally with two large,
rather high and broad pilasters that unite apically (fig. 165b), taper
abruptly in midsection down to atrium, one becoming weakly split in
midsection, the other with a. thick, lateral upward extension. Atrium
(Y) up to 1 mm. long, much longer than in most Polynesian genera.
Free oviduct (UV) elongated, simple, equal in length to uterus.
Spermatheca (S) with head appressed to base of albumen gland,
shaft inserting just on oviducal side of penioviducal angle. Vagina
(V) very short, almost absent in some examples.
Free muscle system as in E. fricki.
Anterior parts of digestive system as in E. fricki.
Jaw of narrow, partly fused, indistinct lamellar plates.
Radula with more than 88 rows, central tooth about 13,u square,
6 laterals with 12-14 marginals.
(Based on BPBM 16556, seven fragmentary examples.)
Endodonta marsupialis Pilsbry & Vanatta,
1906. Figure 167a-b.
Helix lamellosa Pfeiffer. 1845 (not Ferussac, 1824), Zeit. Malak., 2,
p. 85; Pfeiffer, 1848, Mon. helic. viv., 1. pp. 184-185 (partly);
Deshayes, 1851. Hist. Nat. Moll. terr. fluv., 1, p. 369 (Latin
description) — Sandwich Islands; Pfeiffer, 1852, Syst. Conchyl.
Cab., Helix. 1. 12, (2), pp. 197-198, pi. 100, figs. 6-9 - Oahu
(plate published in 1850); von Martens, 1860, Die Heliceen, p. 90;
Tryon, 1887, Man. Conchol., (2),3, p. 67, pi. 12, figs. 32-34.
Patula (Endodonta) lamellosa Clessin, 1881 (not Ferussac, 1824),
Nomen. Helic. viv., p. 96 — Oahu (partly).
Endodonta lamellosa Ancey, 1889 (not Ferussac, 1824), Bull. Soc.
Malacol. France. 6. p. 186 - Oahu (partly); Pilsbry, 1893, Man.
Conchol., (2), 9, p. 25; Sykes, 1900, Fauna Hawaiiensis, Moll., 2,
(4), p. 287 (partly).
Endodonta marsupialis Pilsbry & Vanatta, 1906, Proc. Acad. Nat.
Sci., Philadelphia, 57, p. 784, pi. 43, figs. 1, 2 - Oahu, Hawaiian
Islands; Cooke. 1928. Bull. B. P. Bishop Museum, 47, pp. 21-24,
fig. 6 (anatomy) — west slope of Mt. Tantalus, above Pauoa
Vallev, Oahu. Hawaiian Islands.
SYSTEMATIC REVIEW
381
Diagnosis. — Shell large, diameter 6.64-7.76 mm. (mean 7.20
mm.), with 6'4 - 6'/2+ rather tightly coiled whorls. Apex and spire
markedly elevated, rounded above, last whorl not descending more
rapidly, H/D ratio 0.475-0.485 (mean 0.480). Umbilicus secondarily
narrowed to form brood chamber, early whorls U-shaped, not
decoiling, narrowed by a combination of tighter coiling and inward
columellar-umbilical margin extension during last two whorls,
contained 4.59-5.62 times (mean 5.11) in the diameter. Apical and
postnuclear whorls macroscopically smooth, rarely with a faint trace
of microribbing and often with irregular growth wrinkles. Sutures
weakly indented, whorls flatly rounded down to shallow suprape-
ripheral sulcus. Threadlike keel strongly protruded, lower palatal
margin flat or gently rounded after very shallow subperipheral
sulcus, baso-umbilical margin acutely angled with distinct keel.
Walls of umbilicus flattened. Aperture subquadrangular, flattened
above, weakly rounded below protruded threadlike keel, inclined
about 35° from shell axis. Parietal barriers 2, extending posteriorly
slightly less than one-quarter whorl: upper quite high and very
slender with rather sharp anterior descension, main arm not
expanded, twisting upward posteriorly with a broad, moderately
expanded lateral bifid portion posteriorly; 2nd distinctly lower,
moderately expanded and serrated posteriorly, with gradual descen-
sion to anterior threadlike third that terminates opposite end of
upper parietal. Columellar barrier high and bladelike, weakly
expanded above posteriorly, slightly twisted downwards from plane
of coiling, with gradual anterior descension almost to lip edge.
Palatal barriers 5, extending posteriorly a little more than one-eighth
whorl, with (59.3 per cent) or without (40.7 per cent) a suprape-
ripheral trace, only rarely (2.3 per cent) with a subperipheral trace:
first 3 palatals high, bladelike, moderately recessed, coequal in
height, with progressively more gradual anterior descension; 4th
subperipheral, reduced in height and length, identical to 3rd in
shape; 5th supraperipheral, posterior expanded portion equal in
height to 3rd, with very gradual anterior descension to threadlike
portion, much less recessed anteriorly.
Range. — Known only from Mount Tantalus,
directly above Pauoa Valley, Koolau Mountains,
Oahu, Hawaiian Islands.
Material. — Hawaiian Islands: Oahu, Mount
Tantalus, above Pauoa Valley (2 specimens, FMNH
116902).
Remarks. — The relatively high spire, narrow
umbilicus with the last two whorls developing a basal
sinus that narrows the umbilicus, and large size easily
separate E. marsupialis from E. lamellosa.
Major radial sculpture is absent and there is only
a weak supraperipheral sulcus. As usual, the upper
parietal is bifid, but the other barriers are simple. Of
the 86 specimens examined by Cooke (1928, p. 22), 59.3
per cent had one supraperipheral trace and 40.7 per
cent lacked a supraperipheral trace. Only 2 of 86
examples (2.3 per cent) had a subperipheral trace. As
in E. lamellosa, all individuals had 5 major palatals.
Umbilical narrowing to form a brood chamber is
accomplished differently than in Libera, Gambio-
donta, or Pseudolibera (see pp. 28, 384, 431, respective-
ly). Two whorls before the aperture, the baso-
columellar margin starts to grow inward, forming a
distinct sinus (fig. 167a). The upper parietal margin
does not follow the inwardly extended sinus of the
preceeding whorl (as it does in Libera), giving an
"overlapping" effect to last whorl growth. The extent
of this narrowing is comparatively minor, since the
early whorls do not decoil nearly to the extent seen in
Libera or Gambiodonta.
Cooke (1928, pp. 22-23) indicated that E. marsu-
pialis was characterized by having the oviduct and
penis "distinctly twisted or kinked" and "folded two or
three times." These differences are artifacts produced
through partial contraction of the animal into the
shell and should be given no systematic weight. Size
differences in the albumen gland and spermatheca
may be seasonal. There is an important difference in
penial length. Three dissected individuals of E.
marsupialis had penes 12.0, 14.0, and 15.0 mm. long.
The insertion of the vas deferens into the penis was
proportionately lower down than in either E. lamel-
losa or E. fricki. No material was dissected during this
study.
Endodonta fricki (Pfeiffer, 1858). Figures 163;
164; 167g-h.
Helve fricki Pfeiffer, 1858, Proc. Zool. Soc., London, 1858, pp. 21-
22 - Sandwich Islands; Pfeiffer, 1859, Malak. Blatt., 6, p. 11 -
Sandwich Islands; Pfeiffer, 1868, Mon helic. viv., 5, p. 219;
Pfeiffer, 1876, Mon. helic. viv., 7, p. 255; Tryon, 1887, Man.
Conchol., (2), 3, p. 67, pi. 12, figs. 35, 36.
Helix lamellosa Pease, 1871 (not Ferussac, 1824), Jour, de
Conchyl., 19, p. 96 (partly) — Oahu, Hawaiian Islands.
Endodonta lamellosa Pease, 1871 (not Ferussac, 1824), Proc. Zool.
Soc., London, 1871, p. 474 - Oahu (partly); Pilsbry, 1893, Man.
Conchol., (2), 9, p. 25. pi. 4, figs. 40 and 41; Sykes, 1900, Fauna
Hawaiiensis, Moll., 2, (4), p. 287 (partly) — Waianae Mts., Oahu;
Pilsbry & Vanatta. 1905, Proc. Acad. Nat. Sci., Philadelphia, 57,
pp. 783-784, pi. 43. figs. 7, 8 (partly).
Endodonta fricki (Pfeiffer), Ancey, 1889, Bull. Soc. Malacol.
France, 6, pp. 186-187; Pilsbry, 1893, Man. Conchol., (2), 9, p. 25;
Cooke, 1928, Bull. B. P. Bishop Museum, 47, pp. 24-27, fig. 7
(anatomy).
Helix (Endodonta) fricki Pfeiffer, Baldwin, 1893, Catalogue Land
and Fresh Water Shells, p. 16.
Diagnosis. — Shell very large, diameter 8.03-10.1 mm. (mean 8.99
mm.), with 6-7 rather loosely coiled whorls. Apex almost flat, spire
slightly elevated, last whorl not descending more rapidly, H/D ratio
0.329-0.476 (mean 0.407). Umbilicus rather widely open, U-shaped,
last whorl or whorl and a half decoiling rapidly, contained 3.17-4.17
times (mean 3.66) in the diameter. Apex smooth, postnuclear whorls
without visible microsculpture, growth wrinkles relatively regularly
spaced. Sutures not indented, whorls flat down to shallow
supraperiphera! sulcus. Knife-edge keel moderately protruded, lower
palatal and basal margins evenly and flatly rounded to almost right-
angled umbilical margin, which may be slightly keeled. Walls of
umbilicus flat. Aperture subquadrangular, flattened above and below
slightly protruded knife-edge periphery, inclined about 40° from shell
axis. Parietal barriers 2, extending posteriorly three-sixteenths of a
whorl: upper a high slender blade with gradual descension from the
middle, posteriorly twisted upwards with a short, broadly expanded
lateral bifid portion on posterior third; 2nd distinctly lower, anterior
third threadlike, posterior portion often distinctly bifid, but never as
strongly as 1st parietal. Columellar barrier a high lamella, lying
parallel to plane of coiling, with gradual anterior descension midway
across columellar callus. Palatal barriers 4, extending posteriorly
slightly more than one-eighth whorl, usually with two, but
sometimes with one or three accessory traces: lower 3 subperipheral,
high, moderately to deeply recessed, with progressively more gradual
anterior descension, 1st lower than 2nd and 3rd; 4th supraperipheral,
posterior elevated portion hooked outward, with very gradual
anterior descension, much longer and less deeply recessed. Palatal
382
SOLEM: ENDODONTOID LAND SNAILS
traces normally between 3rd and 4th, a larger subperipheral and a
smaller supraperipheral, occasionally with a second subperipheral
trace present.
Description. — Shell very large, with 63/i normally coiled whorls.
Apex and spire moderately elevated, rounded above, last three-
quarters of body whorl deflected slightly below periphery, H/D ratio
0.443. Apical whorls l'/2, sculpture eroded. Remaining whorls with
low, irregular, protractively sinuated growth wrinkles, without major
ribbing or microsculpture. Sutures very shallow, whorls flat with a
slight supraperipheral sulcus, somewhat flattened on base of whorl.
Periphery acutely keeled, very slightly protruding into a carina,
becoming more rounded near aperture. Color light yellow-white with
irregular reddish-brown flecks and small maculations. Umbilicus U-
shaped, barely decoiling, contained 3.48 times in the diameter, whorls
flattened internally with moderately indented sutures, outer margin
of umbilicus somewhat shouldered. Aperture subquadrangular, flat
above periphery, somewhat flattened directly below with strongly
rounded basal margin, inclined about 30° from shell axis. Parietal
barriers 2: upper slightly more than one-eighth whorl, narrow,
strongly elevated, with sharp anterior descension, becoming broadly
expanded and sinuately twisted upward posteriorly with a lateral
lower bifid extension on posterior third; lower parietal moderately
recessed within aperture, simple and crescentic, slightly lower than
the upper and only weakly expanded above. Columellar barrier
located at basal margin, a high, V-shaped ridge with gradual anterior
descension, slanting across heavy columellar callus almost to lip
edge. Palatal barriers 4, with two accessory traces: lower 3 palatals
moderately elevated, short, crescentic, progressively further recessed
within aperture, gradually decreasing in size with 3rd flattened
above; 4th palatal elongated, only moderately recessed, with narrow,
high, V-shaped anterior portion, posterior half becoming twisted
laterally toward the periphery at a 90° angle, extending more than
one-eighth whorl. Accessory traces located between 3rd and 4th
palatals, lower subperipheral, a very short, low ridgelike knob
situated just below peripheral margin and deeply recessed within
aperture; upper palatal trace even lower, with more gradual anterior
descension, equally recessed, situated just above periphery. Colu-
mellar wall and most of outer palatal wall with a heavy callus
gradually decreasing in prominence. Height of lectotype 3.33 mm.,
diameter 7.52 mm.
Lectotype. - Hawaiian Islands. BMNH 1962716/1,
ex Hugh Cuming collection.
Range. — Widely distributed in Waianae Mts.,
Oahu, Hawaiian Islands.
Paratype. - BMNH 1962716/2.
Material. — Hawaiian Islands (4 specimens,
BMNH 1962716/2, FMNH 81972): Oahu (2 specimens,
FMNH 154482), Kawaiiloa Valley (6 specimens,
FMNH 53041); Makalea (24 specimens, FMNH 53042,
FMNH 111526); Puu Paua (1 specimen, FMNH
90621); Nanakuli Valley (2 specimens, BPBM 127996);
Lualualei, Halona, below Pohakea Pass (5 specimens,
BPBM 128063).
Remarks. - The very large size, relatively low
spire, outward extension of the upper palatal, and
presence of only 4 major palatals are diagnostic. The
outward deflection of the upper palatal is shared with
E. laminata and not found in any other described
species.
Major radial sculpture is absent from the
postnuclear whorls and there is only a weak suprape-
ripheral sulcus. Umbilical decoiling is marked on the
last whorl, with the earlier whorls flatsided and barely
decoiling to perfectly U-shaped. The umbilical margin
is sharply angled. Cooke (1928, p. 25) demonstrated
significant interpopulational differences in umbilical
width (and probably rate of decoiling). The close
similarity of umbilical width in measured material
used for this study (table XCVIII) should not mislead
future workers.
The apertural barriers differ from the other Oahu
species in having only 4 major palatals, with the top of
the upper deflected outwards. The upper parietal is
markedly bifid and often the lower weakly bifid.
Number and position of palatal traces seems to be
variable. In 40 specimens I examined, 35 had two
traces, one just above and the other just below the
periphery; three had only the single supraperipheral
trace; and two had a third trace present below the
periphery in addition to the normal two. In colonies
studied by Cooke (loc. cit.), the percentage with two
subperipheral traces ranged from 18-41 per cent.
Material dissected by Cooke (1928, pp. 25-26) from
Lualualei, Halona, below Pohakea Pass, Waianae
Mountains (BPBM 128063) also was used in this
study. Since only partial specimens of E. lamellosa
were available, detailed studies were made of E. fricki
(figs. 163, 164) to fix the name Endodontidae.
Differences from E. lamellosa are discussed under that
species.
Differences between the three dissected species of
Endodonta have been discussed above. Of general
interest was the presence of three eggs fastened inside
the umbilicus of one dissected example. Flatly ovoid,
the eggs were 0.79-0.82 mm. in length, 0.59-0.64 mm. in
greater diameter, and 0.49-0.54 mm. in lesser diameter.
Apparently, they were cemented in by a mucoid
secretion (turned white and flaky in the preservative).
All were partially coated with grains of red dirt. None
of the eggs contained a formed shell, although in one
embryo the foot could be distinguished.
Description of soft parts. — Foot long and slender (fig. 163a), not
tapering posteriorly, bluntly rounded behind, truncated anteriorly
with head projecting slightly in front of foot. Pedal grooves rather
low on foot, suprapedal much weaker than pedal, both grooves
uniting over tail. Sole undivided longitudinally, smooth, without
transverse corrugations. Tail without middorsal groove, caudal foss
or caudal horn, bell-shaped in cross-section. Slime network very
finely textured, rectangular, more prominent on tail than head
region. Ommatophores very long. Gonopore a short slit located below
right ommatophore, above and slightly behind right rhinophore.
Color in preservative very light yellow-white, no darker
markings. Tip of ommatophores black, muscular portion brownish.
Mantle collar (MC, fig. 163b) short, thick, with bluntly rounded
anterior edge. Pneumostome in parietal-palatal angle, masked by
thickened edges of mantle collar, but without development of
distinct lobes. Anus and pneumostome share common opening. Anus
(A) opening just inside mantle collar with a distinct groove
continuing through mantle collar in pneumostomal opening. Mantle
glands (MG) extending very far onto lung roof. Entire area of mantle
collar and mantle glands strongly indented by apertural lamellae in
preserved material.
Pallial cavity (fig. 163e) extending apically for about one whorl,
very narrow. Lung roof clear, without any traces of color patches or
speckling. Kidney (K) slightly more than one-quarter length of
SYSTEMATIC REVIEW
383
pallia! cavity, slender, with its base abutting on loop of intestine and
reaching up to hindgut on upper margin. Ureter ( KD) sigmurethrous,
incomplete, opening at anterior edge of rectal kidney arm, without
any groove to pneumostomal area. Heart (H) fairly large, angled in
relation to hindgut, less than half length of kidney. Principal
pulmonary vein (HV) long, unbranched until nearly reaching mantle
glands, which are liberally supplied with venation.
Ovotestis (G, figs. 163c; 164a) composed of palmately clavate
alveoli in numerous clumps strung along single collecting tubule,
imbedded in digestive gland (Z) above intestine-stomach apical
margin, but stopping far short of soft part apex (fig. 163c).
Hermaphroditic duct (GD) exceedingly slender and thin in region of
ovotestis, becoming a slim muscular tube just below stomach apex.
Near lower margin of stomach, hermaphroditic duct enlarges greatly,
runs past base of stomach to middle of albumen gland (GG), narrows
abruptly, then reflexes inward to albumen gland, joining shaft of
talon (GT). Albumen gland finely textured, elongated, lying above
pallial cavity, with head of spermatheca pressed into outer side.
Talon (fig. 164b) with slender duct and moderately expanded,
tapering head, opening directly into prostate-uterus. Just before
joining talon, last part of hermaphroditic duct weakly iridescent.
Prostate (DG) rather short, composed of comparatively few large
acini entering a separate very slender tube partly masked by walls of
uterus (fig. 164d), with shaft of spermatheca (S) lying along upper
prostate-uterus margin for lower two-thirds of length, crossing during
apical third to top of prostate with head of spermatheca starting its
expansion at upper end. Top of prostate large, partly enfolding
uterine section, base of prostate narrow, partly enfolded in lower
uterine chambers. Uterus (UT) bipartite: upper section (UTi, fig.
164a) a very thin tube occupying more than half the length; lower
chamber (UT2> rather broadly expanded, weakly pustulose intern-
ally, opening into free oviduct (UV).
Vas deferens (VD) continuing from tube of prostate, equal in
width to spermathecal shaft, lightly bound to penioviducal angle and
rather firmly anchored to penis (P). No differentiated epiphallus. Vas
deferens entering (DP, fig. 164a, c) laterally, slightly below apex of
penis (P), just to one side of a large pilaster (PP). Penis very long,
extending well into visceral hump, cylindrical, with thin smooth
muscular walls. Internally (fig. 164c) with two sets of longitudinal
pilasters (PP), smoothly muscular and split apically, uniting where
penial retractor (PR) inserts, becoming single about one-quarter of
way down, running parallel to near base where they unite. Edges of
pilasters free and slightly extended upward. Below junction of
pilasters is a weak constriction of the wall, followed by entrance to
atrium (Y). Latter a distinctly separate, but short tube. Walls of
penis and atrium with very weak glandular pustulations.
Free oviduct (UV), very long, thin-walled, much broader than
vas deferens apically, tapering basally. Spermatheca (S) long, stalk a
thin tube, lying along free oviduct and prostate, expanded head lying
above pallial cavity, imbedded in albumen gland and head of
prostate. Vagina (V) scarcely separable from atrium. Walls of free
oviduct, spermatheca and vagina with a few longitudinal pilasters.
Buccal mass (fig. 164e) elongated, not elevated posteriorly, with
very small generative sac. Buccal retractor attaching in U-shaped
fan slightly behind midpoint of buccal mass, not split. Esophagus (E)
entering buccal mass at midpoint of upper surface, a slender but
solid tube with longitudinal pilasters, extending past apex of pallial
cavity along inner margin. Just past apex of pallial cavity (fig. 164f),
esophagus expands rather rapidly to form stomach (IZ). For first
section above pallial cavity, hindgut follows parietal-palatal margin
with stomach occupying parietal wall. A slender strip of digestive
gland separates stomach and hindgut. Latter angles gradually
outward onto palatal wall. About one-quarter whorl past pallial
cavity, stomach reaches parietal-palatal margin, thus occupying
entire parietal and palatal walls, intestine, digestive gland and
hermaphroditic duct being restricted to basal-umbilical walls. Total
apical extension of stomach one whorl. About one-eighth whorl from
apex of stomach, it narrows slightly, then tapers and loops
downward to a sharply constricted stomach-intestine junction (fig.
164f). Stomach walls very thin, junction point and recurved section
thicker. First part of intestine (I) following basal-columellar margin
forward to base of kidney, then looping upward along outer margin
to just below hindgut (HG), turning apically and downward to just
above initial intestinal part, then looping upward just below parietal-
palatal margin and running forward as hindgut. Latter soon reaching
parietal-palatal margin and continuing forward to anus (A).
Salivary glands (OG, fig. 164e) white, flanking esophagus and
touching but not united above. Ducts (OGD) of salivary gland
straight, passing into buccal mass at sides of esophagus.
Digestive gland extending from apex of soft parts to pallial
cavity, much darker in color than ovotestis, consisting of narrow
fingerlike lobes in region of stomach and intestinal looping.
Free muscle system simple and elongated. Right ommatophoral
retractor passing between penioviducal angle. Right rhinophoral
retractor passing outside penioviducal angle, uniting with
ommatophoral retractor about one-quarter whorl into visceral hump.
Left ommatophoral and rhinophoral retractors uniting in same area.
Both tentacular retractors merge laterally with tail fan about
midway from tip of insertion of tail fan on foot to apex of columellar
retractor. Buccal retractors split well behind buccal mass, inserting
in U-shaped fan (fig. 164e) less than one-quarter of distance from
posterior margin of buccal mass; very slender posteriorly and
merging with columellar retractor just above apex of pallial cavity.
Tail fan fragmented into many strands radiating to sides of foot and
base of visceral hump. Penial retractor (PR, fig. 164a) long, stout,
merging with columellar retractor slightly above point of origin for
buccal retractor. Apex of columellar retractor situated about one-
half whorl above apex of pallial cavity.
Jaw of very fine, narrow, partly fused lamellar plates.
Radula only mounted in fragments. Central tooth about llju
wide and 13fi long, usually with 6 laterals and 18-19 marginals.
(Based on BPBM 128063, five adult individuals.)
Genus Pseudolibera, new genus
Large Endodontidae in which the umbilicus is modified to form
a brood chamber by inward growth of the last l'/2 whorls. Apical
sculpture consisting of prominent, rather narrow radial ribs,
interspersed with finer riblets. Postnuclear sculpture of prominent,
rounded, somewhat protractively sinuated radial ribs, too worn for
counting in the only adult specimen, that are reduced on shell base.
Strong secondary spiral cording visible on base of adult shell. Whorls
about 5'/2, spire moderately and almost evenly elevated, slightly
rounded above. Periphery strongly protruded into a rather sharp
keel. Parietal wall with single, medially placed, high, bladelike
barrier, extending for more than one-half whorl posteriorly,
apparently with gradual anterior descension. No columellar or
palatal barriers present. Anatomy unknown.
Type species. — Pseudolibera lillianae, new spe-
cies.
Formation of an umbilical brood chamber
produced similarities to both Libera and Gambia-
donta. Pseudolibera's method of brood chamber
closure is more like that of Libera, but the general
shape and protruded keel resemble Gambiodonta. The
latter has many more apertural barriers, a more
dome-shaped appearance and apical sculpture of
quite heavy radial ribs. Libera has more apertural
barriers than Pseudolibera (but fewer than Gambio-
donta), lacks a protruded keel, and has very similar
apical sculpture. In having only a single parietal
barrier of great length, Pseudolibera recalls the
Society Islands Nesodiscus. The genus has a broadly
open umbilicus in which eggs are deposited and
sometimes sealed in by a mucus membrane (fig. 151).
384
SOLEM: ENDODONTOID LAND SNAILS
The characters of apical sculpture, single parietal
barrier, very narrow keel, and gradual umbilical
closure effectively separate Pseudolibera lillianae from
both Gambiodonta and Libera. As its name suggests,
the resemblance is closer to Libera than to Gambio-
donta.
Only two specimens were available, a large and
badly worn adult that Cooke (1934, pp. 5-6) listed as
"Libera sp.," and a very small juvenile specimen that
Aubert de la Rue and Soyer (1958, p. 365) identified as
Endodonta obolus. Apical and early post-apical sculp-
ture is well preserved on the juvenile, while the adult
gives evidence of the pattern used in umbilical closure.
Despite this limited material, Pseudolibera is
obviously generically distinct.
Umbilical closure is achieved essentially as in
Libera. After the umbilicus reaches maximum diam-
eter, growth stabilizes for about one whorl, then a
gradual inward growth of the lower whorl edge
commences. One whorl before cessation of growth, the
rate of inward movement of the columellar-basal
margin accelerates for slightly more than one-half
whorl, stabilizing there for the last one-quarter whorl
of basal-columellar margin growth. The leading edge of
the columellar wall occupies the last portion of the
final whorl of growth.
The presence of two endemic genera, Pseudolibera
and Kleokyphus, on Makatea is quite surprising.
Pseudolibera lillianae, new species (Cooke &
Solem). Figure 168a-b.
Libera sp., Cooke, 1934, Occ. Pap. B. P. Bishop Mus., 10, (11), pp.
5-6 _ Makatea. Tuamotu Islands.
Endodonta obolus Aubert de la Riie and Soyer, 1958 (not Gould,
1846), Bull, Mus. Nat. d'hist. nat., (2), 30, (4) pp. 356-357 -
Makatea, Tuamotu Islands.
Diagnosis. — Shell large, diameter 6.42 mm., with 51X2 normally
coiled whorls. Apex and spire moderately and almost evenly
elevated, slightly rounded above, last whorl not descending more
rapidly, H/D ratio 0.487. Umbilicus constricted to form a brood
chamber by growth of last V-'i whorls. Apical sculpture not clearly
differentiated from post-apical. Postnuclear whorls with prominent,
rounded, rather closely spaced, strongly protractively sinuated radial
ribs, whose interstices are less than twice their width. Radial
sculpture greatly reduced on shell base. Microsculpture a lattice of
very fine radial riblets crossed by slightly finer and more crowded
spiral riblets, with strong secondary spiral cording developed
particularly on base of shell. Sutures shallow, whorls somewhat
flattened laterally above strongly protruded, very narrow keel, with
distinct sub- and suprasutural sulci. Shell base flatly rounded.
Aperture subquadrangular, periphery strongly rostrate, inclined
about 20° from shell axis. Parietal wall with a single medially placed
barrier, extending more than one-half whorl posteriorly, relatively
thin and not expanded above, with gradual anterior descension. No
columellar or palatal barriers present.
The presence of only a single parietal and the
absence of palatal and columellar barriers at once
separates Pseudolibera lillianae from any species of
Gambiodonta or Libera, the other Polynesian genera
with an umbilical brood chamber. Nesodiscus from the
Society Islands is similar in the structure of the
parietal barrier, but differs most obviously in the
character of its ribbing and the widely open umbilicus.
Description. — Shell large, with 5'/2 normally coiled whorls. Apex
and spire moderately and evenly elevated, slightly rounded above,
last whorl not descending, H/D ratio 0.487. Embryonic whorls 1%,
sculpture mainly eroded, but traces of very large, broadly rounded
radial ribs remain in sutures. Postnuclear whorls with remnants of
protractive, broadly rounded radial ribs whose interstices are about
equal to their width, with faint traces of close set spiral cords about
one-half the diameter of the radial ribs. Base of shell with co-equal
radial and spiral cords. Sutures shallow, whorls flattened above with
slight supra peripheral sulcus. Periphery of body whorl an irregularly
protruded knife-edge carina with a slight sulcus above and below.
Base of shell gently rounded. Umbilicus constricted into brood
chamber by the gradual protrusion of the basal lip of the last whorl
and a half. Umbilical opening ovate, 1.32 mm. by 1.09 mm. in size.
All color leached from shell. Aperture subquadrangular with rostrate
outer margin. Parietal wall with single, long, very high bladelike
barrier, extending beyond line of vision despite a three-sixteenths of
a whorl break in outer lip of aperture. Columellar wall with heavy
white callus. Remains of palatal wall without barriers. Height of
holotype 3.13 mm., diameter 6.42 mm.
Holotype. — Tuamotu Islands: Makatea, 1 mile
inland at 250 ft. elevation. Collected on a hillside
around roots of a plant by Mrs. G. P. Wilder on
October 24, 1932. BPBM 115805.
a
FIG. 168. a-b, Pseudolibera lillianae, new species. Makatea,
Tuamotu Islands. Holotype. BPBM 115805. a, side view; b, basal
view. Scale line equals 1 mm. Drawings by YK reproduced through
the courtesy of Bernice P. Bishop Museum.
SYSTEMATIC REVIEW
385
Range. — Makatea, Tuamotu Islands.
Paratype. — Paris.
Material. — Makatea, 1 mile inland at 750 ft.
elevation (1 specimen, BPBM 115805); Makatea (1
specimen, Paris Museum).
Remarks. — The single juvenile paratype shows
details of the apical and early postnuclear sculpture in
the shell umbilicus. Although too badly broken for
measuring, it reveals that the parietal barrier extends
posteriorly for over one-half whorl. The adult speci-
men shows that, as in Gambiodonta grandis, the
major radial ribs are greatly reduced on the shell base.
The specific name lillianae is in honor of its
collector, the late Mrs. G. P. Wilder. It was the
intention of Dr. Cooke to use this name and I have
accepted it here.
Genus Libera Garrett, 1881
( = Garrettia Cossman, 1910 not Paetel, 1873 and Garrettina
Thiele, 1931)
Jour. Acad. Nat. Sci., Philadelphia, 9, (1), p. 33.
Medium to very large-sized Endodontidae in which the
umbilicus is secondarily narrowed to form a brood chamber by
gradual inward growth during the last two whorls of growth. Apical
sculpture typical, not enlarged. Postnuclear whorls with normal
(bursatella, cookeana, micrasoma. recedens, gregaria), very widely
spaced (umbihcata, retunsa, streptaxon), reduced (dubiosa. spuria.
tumuloides), coarsened (incognata, jacquinoti, fratercula, subcai'er-
nula) or no (heynemanni, garrettiana) major radial sculpture.
Secondary spiral cording present in those with normal (except
cookeana) or widely spaced major radial ribbing, absent in those
with coarsened sculpture, intensified in the spuria-dubiosa-garret-
tiana complex. Apex and spire markedly elevated (flattened in
streptaxon, recedens, gregaria), often rounded above. Body whorl
normally with weakly to strongly protruded keel, rounded in
retunsa, only angulated in micrasoma, cookeana, and some
bursatella. Supraperipheral and subperipheral sulci prominence
correlated with degree of peripheral protrusion. Whorls 6% - 8, rather
tightly coiled, lower counts in smaller species. Parietal barriers
normally 2 (only 1 in retunsa and tumuloides), extending posteriorly
to line of vision or beyond, shorter in bursatella, cookeana, retunsa;
normally equal only in umbilicata and micrasoma; all other species
with lower reduced, either having a threadlike anterior extension or
deeply recessed. Columellar barrier normally absent in micrasoma,
bursatella, incognata, fratercula fratercula, and tumuloides; present
or absent in retunsa and fratercula rarotongensis; medium-sized to
large and usually deeply recessed in remaining species. Palatal
barriers normally 3, frequently (bursatella, micrasoma, incognata,
subcavernula, fratercula rarotongensis) reduced to 2, absent in
retunsa, normally 1 in tumuloides, the typical endodontid number of
4 in jacquinoti, fratercula fratercula, dubiosa, spuria, garrettiana.
Pallial region elongated, sometimes with kidney laterally compressed.
Genitalia typical. Penis short to long, internally with two moderately
to greatly elevated pilasters of varying prominence and folding. Vas
deferens entering penis slightly to moderately below penial apex.
Penial retractor originating on diaphragm, inserting directly onto
penis head. Spermathecal shaft inserting directly onto penioviducal
angle. Jaw and radula typical in dissected species.
Type species. — Pitys cavernula Garrett, 1872 ( =
Helix subcavernula Tryon, 1887) by subsequent desig-
nation of Pilsbry (1893-1895, p. 23).
Considerable confusion and uncertainty has exis-
ted concerning both the proper generic name and the
identity of species described during the middle 19th
century. Garrettia Cossman, 1900, and Garrettina
Thiele, 1931, were proposed as replacement names for
Libera Garrett, 1881, under the mistaken impression
that Libera was preoccupied by a vaguely proposed
suprageneric grouping of De Haan (see Pilsbry, 1893-
1895, p. 23 for a discussion of this problem). Libera
Garrett, 1881 is available.
The confusion over specific names is traceable to
several factors. Helix bursatella Gould, 1846, was a
mixture of several species and has not been restricted
previously. It has been interpreted differently by every
author. Pfeiffer's names heynemanni and coarctata
were misidentified by Garrett (1884). Pfeiffer himself
seemed totally confused by bursatella, coarctata,
jacquinoti, cavernula (of Hombron and Jacquinot, not
Garrett), and turricula. Every paper he published
during the 1850's listed a different combination of
synonyms. Ponsonby (1910) did an excellent job in
sorting out literature references, but he did not know
that Garrett's concepts of bursatella, heynemanni, and
coarctata were different from Pfeiffer's, and included
them under their nomenclatural citations. For any
interested historian, Ponsonby's list of mid-19th cen-
tury references is exhaustive. Most of these are catalog
or checklist citations that had occasional varieties
designated only by letters and not by valid nomencla-
tural units. I felt no qualms in omitting them from the
present monograph. Many of these references are
unrecognizable in view of the numerous species
delineated below, are based on secondary literature
citations, and have no scientific importance. Refer-
ences cited below are restricted to original descriptions,
figures in monographs, and reports upon new field
collections.
In order to stabilize the nomenclature, I have
selected lectotypes or neotypes for the old names.
Unfortunately, it usually was necessary to work with
vaguely localized sets from old collections. We still
have no exact localities for L. streptaxon, L. heyne-
manni, L. jacquinoti, L. spuria, and L. incognata. For
L. bursatella I have selected a neotype from recently
collected, well-localized materials. It is intended to fix
and stabilize the nomenclature and thus allow work on
field collections unencumbered by nomenclatural
quibbling.
Available material of Libera came from five
distinct periods of collecting. Each produced its own
set of biases. The initial collecting was during
exploratory voyages and resulted in the description of
L. bursatella (Gould, 1846) (which was rediscovered by
the Mangarevan Expedition), L. jacquinoti (Pfeiffer,
1850), L. streptaxon (Reeve, 1852), L. heynemanni
(Pfeiffer, 1862), and L. incognata, new species. None of
the last four have been collected subsequently.
Possibly L. dubiosa Ancey, 1889, and L. spuria Ancey,
1889, date from the same period. Material probably
originating from the U. S. Exploring Expedition (MCZ
386
SOLEM: ENDODONTOID LAND SNAILS
216751) contained L. micrasoma, new species and L.
garrettiana, new species. Both the latter were obtained
subsequently, but the other species are represented in
museum collections only by scattered individuals. The
probable extent of specimen disappearance can be
judged by the fact that although "over 300 individ-
uals" of Libera tumuloides Garrett, 1872, were collect-
ed in 1869, only 72 of these could be located in the
1960's. To what extent the few examples seen of L.
jacquinoti, L. heynemanni, L. streptaxon, and L.
incognata represent size-biased selections is unknown.
Most material dated from the activities of Garrett
between 1860 and 1884. Libera retunsa (Pease, 1864),
L. fratercula (Pease, 1867), L. tumuloides (Garrett,
1872), L. subcavernula (Tryon, 1887), L. recedens
Garrett, 1884, L. gregaria Garrett, 1884, and L.
garrettiana, are new species that were first taken
during this period. Only L. fratercula has been
collected subsequently. Material from both Garrett
and Pease has been distributed widely, traded and
retraded by collectors, with distinct bias resulting. In
Tables CIII and CVI there is clear indication that
Garrett retained large specimens in his collection and
that the Australian Museum, Sydney, eventually
received very small to subadult examples of his species
(see L. subcavernula, L. tumuloides, L. dubiosa, L.
garrettiana). All measurements of material from these
early periods can be used only with caution in view of
this factor. Such size bias in older museum collections
is common (Solem, 1966b, p. 16).
The other important collection was made by the
Mangarevan Expedition from the B. P. Bishop Mu-
seum in 1934. Besides rediscovering Libera bursatella,
they found L. micrasoma, L. umbilicata, L. cookeana,
and L. bursatella orofenensis, all previously unde-
scribed taxa. A detailed analysis of this material and
its bias is presented below.
Extensive material of Libera fratercula, which
occupies a narrow zone near the sea shore on the
various Cook Islands, was collected by Dr. and Mrs.
Peter Buck in 1929 and 1930, then again by Mr. Laurie
Price in 1964 and 1965.
Only single specimens come from other sources.
The limited overlap of species obtained during
different collecting periods suggests that even by 1860
significant portions of the Society Islands land snail
fauna were extinct and that the process accelerated
oetween 1860 and the mid-1930's. No attempt at
collecting on the upper levels of Moorean and Tahitian
mountains has been made recently. From data avail-
able on Rarotonga, I suspect that additional species
may be collected at high altitudes, but that material
taken during the Mangarevan Expedition in 1934
mostly will be extinct.
The documented extent of size and shape bias in
the Garrett material makes use of comparative
measurements somewhat hazardous. Hence statistical
comparisons have been kept to a minimum.
Secondary narrowing of the umbilicus to form a
brood chamber is shared with the genera Gambiodonta
and Pseudolibera. The same phenomenon occurs in
Endodonta marsupialis and Taipidon semi-
marsupialis. Some other species of Endodonta, the
Rapan Kondoconcha othnius, and the Tongan Thau-
matodon euaensis show partial development of this
character. A full discussion of this phenomenon is
given on pp. 27-30. Libera and Gambiodonta are
separated by numerous characters. Gambiodonta (figs.
22a, d, 185) has the apical sculpture consisting of
coarse, broadly rounded ribs; Libera (figs. 31a, 169)
has the typical very fine apical sculpture. Gambio-
donta narrows the umbilicus during about one-quarter
to one-third whorl of growth, subsequent growth for
the remainder of the full whorl serving only to
maintain the relative position of the baso-columellar
margin to the center axis; Libera narrows the
umbilicus gradually over about two whorls of growth,
the pattern altering only in depressed species such as
L. gregaria, L. recedens, and L. streptaxon, where
partial detachment of the parietal wall initiates
closure. Gambiodonta has many accessory apertural
traces, generally 4-5 parietals, and normally 4 palatals;
Libera has no accessory apertural traces (except rarely
in L. micrasoma and L. incognata), generally only 2
parietals and only 2-3 palatals (except the dubiosa
group which has 4). Pseudolibera and Libera show
much greater similarities in sculpture and pattern of
umbilical closure, but Pseudolibera has only a single
very large and long parietal extending posteriorly for
one-half whorl; there are no columellar or palatal
barriers; the periphery is protruded into a very sharp
keel, and the whorl count of 5V> is very low for a large
(diameter 6.42 mm.) shell. While Libera retunsa and
L. tumuloides have only 1 parietal, the average pattern
of Libera is very different from that of Pseudolibera.
The gap between Libera and Pseudolibera in struc-
tural patterns is at least equal to the gap between
Mautodontha and Kleokyphus.
Derivation of the Society Islands Libera from the
Garrettoconcha group of Mautodontha would present
fewest problems. While Mautodontha (Garretto-
concha) parvidens from Huahine, Moorea, and Tahiti
normally has only 2 parietals and thus agrees with the
barriers of Libera, the forms of M. consobrina from
Huahine and M. saintjohni from Borabora provide
better examples of shell shapes that can precede the
formation of an umbilical brood chamber. None of the
above species are suggested in any sense as ancestral to
Libera itself, but they do indicate the pattern of
change needed for Mautodontha to make the shift —
loss of the 1st and 4th parietals; increase in spire
elevation, whorl count and size; retention and/or
widening of the umbilical opening into a U-shaped
instead of a V-shaped pattern; then, much as in
Endodonta, flattening of the umbilical walls and
gradual narrowing of the umbilical opening during the
last portion of shell growth. The smaller species of
SYSTEMATIC REVIEW
387
Libera, such as L. umbilicata and L. micrasoma, have
the parietals of equal length as in most Mautodontha,
and have relatively slight umbilical narrowing,
probably a function of their small size. They both
show specializations in teeth and sculpture. There are
no indications of secondary size reduction and thus
probably they are the closest to the ancestral species
in size and umbilical characters. The other small
species, Libera retunsa, is quite specialized in barrier
reduction, sculpture, extreme deflection of the body
whorl, and is generalized only in respect to the
comparatively minor umbilical narrowing and the
rounded body whorl.
Additional evidence for the derivation of Society
Islands Libera from Mautodontha (Garrettoconcha)
comes from the pattern of sculpture. The high mean
rib counts of those Libera with generalized sculpture
(107-178, micrasoma, bursatella, dubiosa, recedens,
gregaria) agree well with the pattern in the more
generalized Mautodontha (123-153, consobrina, saint-
johni, punctiperforata, parvidens, daedalea) and
greatly exceeds the average counts in other genera
from Eastern Polynesia.
There is sufficient variation within the Society
Islands Libera to suggest that the genus may be
polyphyletic in the sense of having been derived from
two related species groups of Mautodontha. The series
of species Libera dubiosa, L. spuria, and L. garret-
tiana differ radically in character of sculpture and
general appearance from the most typical series. There
is no qualitative difference in umbilical formation and
I have no hesitation in classifying them in the same
genus. So little anatomical material of both Libera
and Mautodontha was available for study, that it is
impossible to suggest exact phylogenies in view of the
confusing shell valuations.
Derivation of the three Cook Islands species, L.
fratercula and its two derivatives, L. subcavernula and
L. tumuloides, could have been from a Cook Islands
stock of Mautodontha for which we have no record, or
could be a secondary dispersal from the Society
Islands. None of the recently extant Cook Islands
Mautodontha show characters tending toward the
brood-chamber pattern. Without study of anatomical
structures in many more Mautodontha and Libera it
will be impossible to eliminate the possibility that
Libera is of polyphyletic origin from different groups
of Mautodontha. Habitat destruction in both the Cook
and Society Islands has proceeded to such an extent
that collection of needed material is very unlikely.
Shell characters are insufficient to allow resolution of
this problem. While Libera may be a grade of
structure that is composed of several parallel lines of
evolution, the separate lines would be very close
phyletically. Inclusion of the derived species within
one genus requires no hesitation.
Within Libera there are no obvious unitary trends
of variation. Instead there are diverse patterns of
FIG. 169. Apical sculpture of Libera bursatella bursatella
(Gould). (MM).
change that show few correlations. The normal
endodontid sculpture of fine radial ribs with three to
eight microradials between each pair of major ribs is
present in most species. The same microradial spacing
holds for species with broadened radial ribs (fratercula,
subcavernula, and to a lesser extent in the very large
jacquinoti). The situation in L. incognata is unknown
because no unworn material was available. Dramatic
increase in rib spacing is seen in L. umbilicata, L.
retunsa, and L. streptaxon, with only L. retunsa
having the microradial spacing increased. In L.
umbilicata and L. streptaxon the number of micro-
radials rises to about 30 and from 12 to 20,
respectively. Reduction and loss of major ribbing has
happened at least twice. In the Cook Islands, there is
some reduction in L. subcavernula followed by loss of
major ribbing in L. tumuloides. In the Society Islands,
there is a graded series in three closely related species,
L. dubiosa having normal sculpture, loss on the body
whorl and lower spire in L. spuria, followed by
complete loss of major radial ribbing in L. garrettiana.
Possibly the much larger and macroscopically smooth
L. heynemanni is part of the same series. Secondary
spiral cording is absent from those species with
broadened major radial ribs and varies from weak or
only on shell base (recedens, gregaria, micrasoma) to
very prominent (streptaxon, retunsa, dubiosa, spuria,
garrettiana). Spacing frequency of the secondary spiral
cording is least in garrettiana (fig. 177c) and greatest
in L. retunsa (fig. 178d).
The above variation in ribbing character is only
partly reflected in the rib spacing variation (table
XCIX). Both increased spacing and broadening of the
ribs can alter the ribs/mm, drastically. Those with
secondarily widely spaced sculpture, umbilicata, re-
388
SOLEM: ENDODONTOID LAND SNAILS
TABLE XCIX. - RIBS AND RIB SPACING IN LIBERA
Name
micrasoma
b_. bursatella
b. orofenerms
cookeana
giegaria
recede OS
dubiosa
umbilicata
fratercula
Mangaia
Mauke
Atiu
Ribs
107. 212.49
(103-117)
119.0*2.76
(98-161)
171. 816. 21
(158-185)
91. 4*2. 06
(85-95)
177.8±4.51
(155-198)
178.2*7.12
(152-198)
125.2±4.68
(111-138)
29. 3±1.77
(26-32)
51.2±2. 15
(43-55)
46.4± 1.31
(36-55)
49.8±1.31
(43-55)
55.0*1.58
(47-67)
83.5±1.22
(74-112)
78.9*2.18
(66-93)
80.0*1.81
(66-93)
83. 0±2.84
(66-105)
Ribs/mm.
7.64*0.150
(7.30-8.39)
7.14±0.175
(6.12-8.95)
10.44*0.585
(8.68-12.02)
3.72*0.051
(3.52-3.84)
8.16i0.201
(7.28-8.98)
9.57±0.425
(8.17-10.53)
7.43±0.486
(5.64-8.51)
2.50*0.127
(2.26-2.69)
3.94*0.252
(2.97-4.43)
2.44*0.078
(1.81-2.91)
2.18*0.042
(2.00-2.34)
1.94*0.136
(1.66-2.47)
4.86*0.068
(3.81-6.13)
4.53*0.158
(3.65-5.60)
5.01*0.100
(4.23-5.77)
4.22*0.135
(3.31-5.44)
tunsa, and streptaxon have between 2.4 and 4.0
ribs/mm., while those with broadened ribs, incognata,
fratercula, and jacquinoti, range between 1.9 and 5.0
ribs/mm. This range undoubtedly is extended on the
lower side by the size correlated rib spacing increment
in jacquinoti, but is a duplicated spacing effect for the
other species. Only in L. recedens, as a secondary
result of extreme body whorl deflection, and L.
bursatella orofenensis, as a result of sharp increase in
rib number, is there a large ribs/mm, average (9.6 -
10.4).
Most species have a typically domed spire, but in
L. streptaxon (fig. 179a) and, to a lesser extent, both L.
recedens and L. gregaria (fig. 175a, e), the spire is flat
or only weakly elevated. In these species the umbilical
closing is altered. Closure is not as gradual and
involves partial detachment of the parietal wall
followed by strong deflection of the body whorl in L.
recedens (fig. 170) and L. streptaxon. This change
allows maintainence of an adequate internal cavity for
egg deposition and the increased deflection permits
adequate closure. While effective in the end result, I
suspect this was a secondary development within
Libera correlated with spire depression, since use of a
thin parietal wall plate provides minimal strength to
the umbilical closure.
Whorl contours depend upon the degree of
peripheral keel protrusion. Only L. retunsa has the
periphery rounded and only L. bursatella, L. cook-
eana, and L. micrasoma have weak peripheral an-
gulation. The remaining taxa have slight to extremely
strong peripheral protrusion. As would be expected,
this is roughly correlated with size increase, the larger
species having greater protrusion of the keel. In all
species with prominent keel development, it is a
threadlike rounded protrusion, not sharply narrowed
and angled as in Pseudolibera, and there are promi-
nent supraperipheral and subperipheral sulci.
While mean whorl count ranges from 6% - 8 + ,
there is no single correlation with size. Two large
species, L. incognata and L. jacquinoti, do have high
whorl counts, but L. cookeana is of equal size and has
a lower count. A comparatively small species, L.
streptaxon, has a high count. Of the smallest Libera,
only L. retunsa has a low whorl count, while the
others reach the median range for the genus.
Barrier variation is equally uncorrelated with size
(table C). In L. bursatella, L. cookeana, and L.
retunsa the parietals are only one-quarter whorl long,
in the remaining species they extend essentially to or
slightly beyond the line of vision. Normal reduction to
only one parietal is found in L. retunsa, the second
smallest species, and L. tumuloides, which is larger
than average but does not reach the upper quartile of
size range. Both of these also are the only species with
normal reduction to less than 2 palatals. In contrast,
the largest species, L. cookeana, L. incognata, and L.
jacquinoti, retain essentially a full complement of
apertural barriers. This is quite different from the
pattern in Nesodiscus, where barrier reduction and
increased size are directly correlated. Columellar
barrier size ranges from very large in L. recedens and
L. gregaria (fig. 175a, e); reduced or absent in L.
retunsa and L. fratercula rarotongensis; to always
absent in L. micrasoma, L. bursatella, and L.
fratercula fratercula. When present, the columellar
barrier normally is deeply recessed.
Variation in anatomy was concentrated in the
pallial region and penial complex. In L. bursatella (fig.
171d) there is significant lateral compression of the
kidney resulting in a "pocket" arrangement at the
posterior margin. In other examined species, the pallial
region followed normal endodontid pattern. Within the
penial complex, the origin of the penial retractor from
the diaphragm was unexpected and the generally only
slightly subapical insertion of the vas deferens into the
penis was slightly unusual. Penial variation concerned
primarily length and pilaster pattern. On Mt. Aorai,
where L. bursatella, L. micrasoma, and L. cookeana
were partly sympatric — L. micrasoma has two equal-
sized, low pilasters; L. bursatella, subequal pilasters,
one of which is higher and rather complexly folded;
and L. cookeana has very unequal pilasters, one of
which is very high and simple (fig. 172a-b), with the
other greatly reduced to absent in the upper half. Size
relationships of the penes are: L. micrasoma, 3.9-4.1
mm. long; L. bursatella 4.3-4.5 mm. long; and L.
SYSTEMATIC REVIEW
389
cookeana, 5.9 mm. long. There is thus both penial size
and pilaster differences between the three sympatric
species on Mt. Aorai. The other species dissected, L.
bursatella orofenensis and both races of L. fratercula,
had penial pilaster patterns that essentially agreed
with those of L. bursatella bursatella, having slight
inequality in pilaster height and the higher one
modestly folded.
The anatomical features of Libera are relatively
conservative. Absence of a fleshy extension to the
penis head and high insertion of the vas deferens agree
with the more generalized taxa. The penioviducal
angle insertion of the spermatheca, moderately ele-
vated pilasters, and very long talon differentiate
Libera from both Nesodiscus and Endodonta. The
complexly folded or elevated penis in Libera ap-
proaches that of Australdonta, but is more similar to
the type seen in Opanara.
While certain species are obviously more closely
related to each other than to the remaining, no clear
hierarchy can be recognized. Libera dubiosa, L. spuria,
and L. garrettiana form one series; L. recedens and L.
gregaria are closely related; L. tumuloides and L.
subcavernula are derived from L. fratercula; L.
bursatella, L. micrasoma, and L. cookeana probably
are closely related. The other species seem relatively
isolated in position, and none of the groups listed
above are obviously related. Either the dubiosa or
bursatella series could be near the ancestral type for
Libera.
Distributional data on Libera are comparatively
sparse and quite unsatisfactory in comparison with
other genera. For five species known only from
material taken prior to Garrett's collections of 1860-
1863, L. streptaxon, L. incognata, L. jacquinoti, L.
spuria, and L. heynemanni, even the island of origin is
unknown or uncertain. For species collected by
Garrett, either between 1860 and 1863 or from 1870 to
1883, there are general island quadrant references that
indicate geographical isolation. From impressions
gained by comparing Partula data in Crampton (1916)
with Garrett's Partula data, I suspect that all his
collections were from relatively low elevations. None
of the Libera species he described or first collected
during this period were obtained by the Mangarevan
Expedition in 1934. On Tahiti, L. retunsa was found
"on the south side" and L. garrettiana (reported by
Garrett, 1884, p. 35 as L. heynemanni) "in several
valleys on the northwest part." On Moorea, L. dubiosa
(recorded by Garrett, 1884, p. 34 as L. coarctata) was
"diffused throughout several valleys on the north and
east side of Moorea," L. gregaria "in two valleys on
the southwest part," and L. recedens was found on the
"lower part of one valley on the west side." While L.
FIG. 170. Body whorl deflection and form of umbilical closure in Libera recedens. FMNH 156777. Scale line equals 1 mm. (SO).
390
SOLEM: ENDODONTOID LAND SNAILS
recedens was stated to be low in a valley and thus can
be presumed extinct, it is possible that populations of
the others are extant. Only L. recedens and L.
gregaria of the above species could be considered very
closely related and possibly subspecies. The
morphologic gap between the two is so large that I
have accepted Garrett's specific separation. L. dubiosa
from Moorea and L. garrettiana from Tahiti are
members of a monophyletic assemblage, but have a
much greater morphologic gap than in the prior case. I
have no hesitation in considering them distinct species.
All Libera collected during the Mangarevan
Expedition were taken above 4,000 ft. elevation. These
involved two partial transects, one by botanists on Mt.
Orofena, the other by malacological assistants and an
entomologist on Mt. Aorai. On Mt. Orofena, Libera
bursatella orofenensis and L. umbilicata, both pre-
viously undescribed taxa, were taken at the same place
(Station 949). Since the latter was found only at that
station, the wider occurrence of L. b. orofenensis does
not alter their sympatry. On Mt. Aorai, L. bursatella
bursatella, L. micrasoma, and L. cookeana were found
at Station 865, and two of the three species at Stations
863, 864, and 866. In each case, L. b. bursatella was
overwhelmingly predominant in numbers, and L.
cookeana was most sparsely represented. The penial
differences at these stations are discussed above.
Both sympatric and allopatric distribution pat-
terns are present in the Society Islands Libera.
Unfortunately, it is probably too late for field
investigations of these patterns.
In the Cook Islands, one species, Libera frater-
cula, is widely distributed near the seashore and there
were two inland derivatives of this species, L. subca-
vernula and L. tumuloides, on Rarotonga. The latter
was restricted to "a small area of about one-half an
acre, and nearly two miles inland," while the former
was "Found plentifully in the mountain ravines."
Neither was collected during 1964 or 1965. Quite
probably they are extinct.
With two exceptions, the ecological occurrence of
Libera is characteristic of the family. Garrett's
references to habitat are repetitious for "on the ground
in forests," "beneath rotten wood," "beneath loose
stones and decaying wood," "congregating in immense
numbers on the under side of loose stones," and
"beneath decaying vegetation." They are restricted to
the ground stratum in heavy forest, generally under
stones or rotting wood. Libera fratercula is found in
coastal forests on several of the Cook Islands and
apparently has become adapted to life in the
comparatively exposed and dry zone of coral boulders
that extends from just above the storm high tide mark
to a little more than 150 yd. inland. They are found
under the coral boulders, but this habitat is relatively
open and thus subject to periodic drying. Hence there
is considerable phenotypic variation even over 200 yd.
intervals within a continuously distributed colony.
This is quite different from the situation seen in wet
forest litter endodontids, where variation between
populations was either at the subspecific level or
virtually absent because of habitat stability.
Libera bursatella bursatella was found to be
abundant "in the axils of ie'ie" (Freycinetia arborea)
at Station 863 on Mt. Aorai. The only other non-
terrestrial records for endodontids are of some Cooke-
concha found in moss on tree trunks, while Price-
concha tuvuthaensis Solem (1973d) was taken on tree
trunks in Lau. Thus the semiarboreal occurrence of
Libera is quite unusual.
Since Libera fratercula occupies a zone with
superabundance of lime, the exceptionally thick shell
and unique method of the young exiting from the
brood chamber (see pp. 418-419 and Solem, 1970)
could evolve quite easily. For other species at inland
and elevated localities where volcanic rocks are far
more prevalent than coralline, lime is much less
abundant and the more conservative pattern of thin
shell and the young exiting through the baso-
columellar margin at the narrowed umbilical opening
is followed.
Inevitably there were a few specimens and
references that were not referable to named taxa, yet
were not present in sufficient quantity for naming.
These are listed as Libera sp. after the species
discussion. Garrett's material from Aitutaki undoubt-
edly was distinct, but all these specimens were
destroyed during World War II. A very unusual form
is represented by a single specimen (RSM 1961.61.40)
from Moorea. The shell is subadult, 5.43 mm. in
diameter, 2.63 mm. high, with 6% whorls. There are 2
parietals, lower with anterior two-thirds threadlike, a
large columellar and 4 palatals, with the 1st greatly
reduced in size. It is obviously related to the dubiosa-
spuria -garrettiana series, but differs in the strongly
protruded cordlike periphery, low spire (H/D ratio
0.484), and relatively strong radial ribbing. The
peripheral protrusion starts after 4'/s whorls near a
repaired break in the shell and may be a simple
abnormality. Possibly this shell should be referred to
L. dubiosa.
KEY TO THE GENUS Libera
1. Prominent major radial sculpture present on body whorl or at
least penultimate whorl 5
No major radial sculpture on body whorl, or penultimate whorl.
2
2. Parietal barriers 2; Society Islands 3
Parietal barrier 1; Rarotonga.
Libera tumuloides (Garrett, 1872)
3. Surface with prominent microribbing and secondary spiral
sculpture 4
Surface macroscopically smooth.
Libera heynemanni (Pfeiffer. 1862)
4. Major radial ribs present on upper spire. *
Libera spuria Ancey, 1889
No major radial ribs present Libera garrettiana, new species
5. Normally 2 or more parietals; 2 - 4 palatals; body whorl
angulated or keeled 6
SYSTEMATIC REVIEW
391
Normally 1 parietal; no palatals; body whorl evenly rounded. parietal high and bladelike, more expanded and elevated on posterior
Libera retunsa (Pease, 1864) third, with gradual anterior descension; 2nd equally high on posterior
6. Major radial sculpture narrow, not broadened; generally three-eighths, anterior half moderately raised, bladelike, with gradual
secondary- spiral cording prominent 11 anterior descension that terminates slightly in front of upper parietal
Major radial ribs broadened and much thicker; no secondary end. Columellar wall flat or weakly convex, with a moderately
spiral cording 7 developed callus, no barriers. Palatal barriers 2, both subperipheral,
7. Major ribs persisting over entire body whorl 8 extending posteriorly more than one-eighth whorl, not so deeply
Major ribs becoming very irregular on body whorl and part of recessed as in most Libera: lower basal in position, a weakly elevated
penultimate whorl Libera subcavernula (Tryon, 1887) threadlike ridge with gradual anterior descension; 2nd slightly higher
8. Mean ribs on body whorl less than 60 9 posteriorly, longer, with more gradual anterior descension.
Mean ribs on body whorl more than 75 10
9. Mean H/D ratio about 0.650; spire rounded above; keel weakly Libera micrasoma has 2 parietals of equal length
protruded; normally 2 palatals; mean diameter about 7.30 that extend posteriorly to the line of vision and is
x,mm--"r;- : •" "•" ...Wteni incogna/a, new species much smaller (table Q than the sympatric Libera
Mean H/D ratio about 0.540; spire not stronglv rounded above; , . „ , . „ T .... ,. •... /~v r
keel strongly protruded; normally 4 palatals; mean diameter bursatella bursatella. L. umblhcata from Mt. Orofena
about 8.50 mm Libera jacquinoti (Pfeiffer, 1850) agrees in the parietal barriers, but is even smaller, with
10. Mean diameter about 6.60 mm.; only 2 palatals. 3 palatals, has comparatively weak and very widely
Libera fratercula rarotongensis, new subspecies spaced radial ribs (mean rib count 29.3). The other
Mean diameter about 5.60 mm.; normally 4 palatals. species of equal size, L. retunsa, has very strong
Libera fratercula fratercula (Pease, 1867) , „
11. Fewer than 70 ribs on body whorl 18 secondary spiral cording, a strongly deflected body
More than 80 ribs on body whorl 12 whorl, and a deeply recessed lower parietal.
12. Palatals normally 2 or 3 13 Description. - Shell very small, with 7 tightly coiled whorls.
Palatals normally 4 Libera dubiosa Ancey, 1889 Apex and early spire almost flat, lower whorls descending sharply,
13. Mean rib counts about 170 - 180 16 H/D ratio 0.633. Apical whorls 1>4, sculpture of widely spaced major
Mean rib counts less than 130 14 radial ribs with two or three minor riblets between and crossed by
14. Adult size less than 6.25 mm.; no columellar; 2 palatals 15 cioseiy spaced, very fine spiral riblets. Postnuclear whorls with high,
Adult size more than 7.00 mm.; 1 columellar; 3 palatals. prominent, roundly lamellate, protractively sinuated radial ribs, 117
Libera cookeana, new species On the body whorl, whose interstices are 2-3 times their width.
15. Parietals equal in length Libera micrasoma, new species Microsculpture of low, rounded radial riblets, five to eight between
Lower parietal deeply recessed. each pair of major ribs, that completely overshadow very closely
Libera bursatella bursatella (Gould, 1846) spaced and extremely fine spiral riblets. Sutures deep, whorls
16. Prominent columellar barrier present 17 strongly rounded above, compressed laterally down to faint and
No columellar barrier. obtuse angulation, evenly and gently rounded on base to sulcus.
Libera bursatella orofenensis, new subspecies Umbilicus modified into a brood chamber by the broad and gradual
17. Body whorl strongly deflected beneath penultimate whorl. constriction of the last two whorls, opening relatively wide, nearly
Libera recedens Garrett, 1884 circular, contained 3.78 times in the diameter. Color yellow horn,
Body whorl not strongly deflected. with broad, reddish flammulations that become zigzagged on shell
Libera gregaria Garrett, 1884 base. Aperture subquadrangular, rounded above and below the
18. Adult diameter less than 4 mm.; spire strongly elevated. obtusely angled periphery, inclined about 20° from shell axis.
Libera umbilicata, new species Parietal barriers 2, extending posteriorly to line of vision: upper
Adult diameter more than 5 mm.; spire flat or depressed. lamellate for its entire length, higher on posterior third; lower with
Libera streptaxon (Reeve, 1852) threadlike anterior half becoming equally elevated posteriorly,
extending slightly beyond end of upper parietal. Columellar wall flat
Libera micrasoma, new species. Figures 171f-h; with a heavy white callus- barriers absent. Palatal wall with 2
, ,70 moderately deeply recessed, short ridgelike barriers that extend more
than one-eighth whorl: upper longer and with more gradual anterior
descension than lower, both subperipheral. Height of holotype 2.81
Diagnosis. — Shell very small, diameter 4.12-4.71 mm. (mean mm., diameter 4 44 mm
4.46 mm.), with 6Vi - 7'/z normally coiled whorls. Apex slightly
protruding or less frequently flat, whorls of spire descending Holotype. - Society Islands: Tahiti, Station 865,
progressively more rapidlv, bodv whorl not or onlv slightly deflected, , ., . . ., , _ „,,„ „ „„,, , , . -~, ,, , ,
,A .• n=cAOC, TT u-i- Mt. Aorai trail at 5,600-6,300 ft. elevation. Collected by
H/D ratio 0.550-0.686 (mean 0.612). Umbilicus secondarily narrowed ' '
to form brood chamber by only moderate inward growth of baso- E- Zimmerman, Y. Kondo, and D. Anderson on
columellar margin, opening circular, contained 2.96-4.80 times (mean September 15, 1934. BPBM 145287.
3.66) in the diameter. Postnuclear sculpture of relatively narrow, «„, . , f,nr. ,. o/~vr> iv j.-
Range. — Mt. Aorai, 5,600-6,300 ft. elevation,
high and prominent, protractively sinuated radial ribs, 103-117 (mean
107.2) on the body whorl, whose interstices are 2-4 times their width. Tahiti, Society Islands.
Microsculpture of fine radial riblets, five to eight between each pair Paratvpes — Same as list of material
of major ribs, crossed by exceedingly fine and crowded spiral riblets
that are visible only under 96 X magnification. Base of shell with Material. — Tahiti: Mt. Aorai trail (Station 865)
traces of very few and indistinct spiral cords, absent from upper a£ 5,600-6,300 ft. elevation (13 specimens, BPBM
surface. Sutures deep, whorls strongly rounded above, flattened 145287-8); valley west of Aorai trail (Station 866) at
laterally down to very weakly angled periphery, lower palatal and ., - . . .„ r>r>nn/c i ..mm
6,000 ft. elevation (6 specimens, BPBM 145293).
basal margins gently and evenly rounded down to marked sulcus
above acutely angled baso-columellar margin, columellar wall flat or Remarks. — At first glance Libera micrasoma
slightly concave inside umbilicus. Aperture ovate, compressed geems tQ be Qnly & smM form of L bursatMa
laterally above and below very weakly and obtusely angled ,71 i • /• , i
• , . ,. , , , ,' , .; bursatella, but the greater length and equal size or the
periphery, inclined about 20 from shell axis. Parietal barriers
normally 2. occasionally with a 3rd (6,3 per cent) or with two small parietal barriers, much smaller size, and stronger
traces (6.3 per cent), extending posteriorly to line of vision: upper sculpture separate the two sympatric species. The
01
co|
,
CO
i
0)1
col
ml
ct,
O
•H|
O
CO)
i
CN
<N CN
(Ml
CO)
t
(N
o
-u
id
o
CO
CO
rH
CO
CO
0
o
•*'
co'
10
IO
CO
CO
o
CO
en
CO
CO
o
H
H
CN
CO
co'
co'
.2
,2
ar
f^
53*
w
bo
BO
CD
IO
rH
en
o
U
co"
•#
•*"
co'
1
g
00
co"
CO
10'
CN
CD'
Cp^
OO
s s?
•*
•
CO
C7i
0
oo1
CO
w
PQ
O
M
3
I
h
O
W
rJ
0
tf
PS
<u
J-l
0)
£
•H
0)
to
.Q
•H
Pi
u-i en
o c
rH
t-
CO
c-
00
rH
r-
rH
C-
§
60"
CN
rH
t>
CO
I-H
OO
oo"
CO
OO
f
I
CO
c-
CN1
CO
rH
C-
CN
rH
t-
00
^H"
0?
CO
co
CO
e-
rH
L—
LO
C-
"^
^v.
"^
00
~^:
l-H
00
rH
rH
CD
CD
CD
CO
CO
00
CO
CO
LO
CN
LO
LO
CD
CN
CO
LO
CO
LO
CO
-t
T
4
00
^
-f
OO
^
^
CN
OO
^
CO
oo"
OO
-1
00
-f
CM
00
CM
00
CO
CO
c-
rH
w
rH
rH
CO
•^
CO
LC
e*
•^
IO
rH
CO
rH
IO
CO
CD
CD
c-
t-
t-
t>
CD
CD
C-
CO
c*
co
OO
B-
CO
t-
CO
CO
OO
CD
CD
CO
co"
CO
CD
f~^
c*
LC
C-
C-
LO
c-
CN
CO
C-
01
CD
t-
cn
CO
f
o
CD
co
CO
c-
CO
LO
t-
CD
i-H
CO
OO
c-
rH
CO
c-
c-
1— 1
CD
CO
en
CD
00
rH
rH
C-
(N
00
O
O
O
o
o"
0*
0*
o
O'
o
o
O
o
0
O
o"
o
o
o
1
1
1
1
Q
<N
CN
L—
c~
41
1C
c
CO
LO
£*,
^p
Tj"
l-H
CO
IO
en
OO
CO
LO
CO
rH
LC
CO
CO
CD
CN
LC
0
LO
o
LC
CN
CO
CD
LO
CO
CO
c-
i
i— i
10
ira
IO
o'
O
Q
o
o
C
O
o
o
o
o
O1
o
0
o
0
0
o
o
C3
rH
CD"
c~
of
en
co"
CN
00
O5
co"
LC
en
en
ar
LO
Tf
co"
CO
o
IO
en"
CO
o
c-
s
X
rH
l-H
c-
CD
LC
LO
LO
*cf
LO
LC
LO
LO
CD
CD
LO
LO
CO
LO
tra
CO
CO
co
O
0
CD
O
0
0*
c>
o
O
O
O'
o
0*
0*
o
o
o
O
o
e-
CO*
00
£r
LO
c-
rH
CO
co"
CN
tr-
c—
CD
CD
CO
CO
LC
en
LO
s
CN
LC
t-
co
CD
V
CD
CD"
CO
00*
c-
c-
00
en
CO
LO
1— 1
OO
CO
CO
t^
c-
I-H
c-
1
i
i
1
1
<N
^i
rH
00
e-
CO
T-Jl
CO
rH
CO
CD
CO
CO
0
IO
*^
CO
en
OO
rH
CO
t"
rH
es!
CO
00
rH
LC
CO
CO
CN
CN
00
•*
OO
CN
l-H
^jT
"•t
^'
c~*
CO*
LO*
^u
^t1'
^j,'
CO
CO
LO*
LC*
CO*
C-*
^
in*
IO
CO*
CD"
of
£^
o'
of
co'
CN'
55"
uX
co"
CN"
0*
*£•'
CO
o"
en"
*
rH
**
CO
rH
CO
L—
CO
•^
00
00
[-
co
0
LO
CO
M-
CO
IO
CN
IO
•*'
LO
LO
c-
CO
LO'
LO*
*
*
CO
•*
CO
CD
t-"
00
IO
CD
CO*
CO*
§
CO
CO
o"
CO
g
0?
if
CN"
01
en"
o
c^
rH
co"
LO
^
0?
o?
f
oo"
1— 1
0~
0
m"
co'
co'
co'
•*'
co"
CO
CO
co'
co'
CN
CO*
CO*
uo
LO'
U5
^f
co'
LO
IO
i
1
1
rH
rH
LO
CO
CD
rH
t-
CN
CO
C71
LC
^Jl
en
cn
CO
CO
c-
LO
Tf
CO
e-
10
t-
CO
LC
CN
(N
CN
LC
eft
en
C-
o
in
CM'
<N
CN
co"
CN"
<N*
CN
CN
CN
CN
<N
CN
CN
co'
co'
CN
CO
co'
CO
ot
o'
sr
55"
C^
co'
LO"
&
eK
C-
rH
o
o
CO
rH
CN
CO
C*
LO
f-
(N
CD
t-
LO
c-
CO
CO
CO
CN
CO*
co"
*
co'
CO
CO
CM'
N
CN
<N
CO*
•
m
•*'
*
CN
*
CO
•*'
C-
LT?
So
QO
CO*
m
o ^
i-H
rH
CO
en
85
CO
cT
u?
rH H
rH
I
CO
o
CO
i-H
CO
rH
00
LO
LO
I-H
LO
LO
rH
CN
LO
rH
rH
rH
00
i
SH 1-J
CN
CO
CO
LO
LC
CO
LC
LC
1
CO
H
LO
LO
CO
c-
co
1
c-
i-H
rH
LO
o
CO
Q 2
g5
H
I— I
85
rH
00
rH
rH
rH
t~* ">
i r^
CO
to
^1
^1
CO
CO
CO
of
o"
06'
X
oo'
C^"
of
W &
z u
co"
CN"
^
co'
-^'
o
\a
o"
§1
CQ
c-
o
rH
pi
rH
en
C-"
c~-
CO
IT-
CN
< ^
0 1
s
s
$'
<
?
s
i-H
00
co'
00
Sg
o
-*
CO
CO
•3
•z,
3
C
a
CD
C
2
-S
£
C1
^^
s
1 1
^j
CJ
t«
't-l
rt
oe
22 -
t, c
3 -S
>— ' aj
0)
S «
a .2
>^
CD
O
C
<
M
3
O £
o
^
X!
XI
SI &C
ui
^
a
u,
J
§
^
0)
f
r3
bilicata
? §
Crt «TJ 2
w 0>
§ ^ P.
(Reeve)
nemann
£ a
^ 1
£ 8
•a
§
3
cr
M
JJ ca
S3 -3
<S H
?r1
nl 3
arotonge
icavernu
E' " Si
****i b 1 i/}
«
c
c9
•r^
t«
>S
M
j_i
g
392
SYSTEMATIC REVIEW
393
apical whorls are of the same size as L. b. orofenensis
(table CI), and thus significantly smaller than those of
L. b. bursatella. Apparently penial sizes and pilaster
patterns differ.
L. micrasoma is quite generalized in structure and
sculpture, with the relatively open umbilicus correlat-
ing with the smaller size. The relatively small palatals
and loss of the 3rd correspond well with the features of
L. bursatella.
Sixteen of 19 examples (84.2 per cent) were adult.
While the diameters of the two populations sampled
did not overlap (table CII), those from Station 865
were adult to gerontic, and those from Station 866
were barely adult. The statistically significant differ-
ence (for diameters, "7" = 4.031) is based on age
differential in this case.
Description of soft parts. — Foot and tail squashed in only
whole example.
Body color yellow-white, without darker markings.
Mantle collar thin and rather narrow, a prominent glandular
extension onto pallial roof.
Pallial region extending one-and-one-quarter whorls apically.
Lung roof clear, without granulations. Kidney about 2.6 mm. long,
rectal arm about 1.2 mm. long, kidney much less compacted than in
L. bursatella. Ureter typical. Heart about 1 mm. long, slightly angled
from hindgut. Principal pulmonary vein unbranched, extending to
edge of pallial mantle collar extension. Hindgut extending one-eighth
whorl above pallial cavity apex, not angling downward from margin.
Ovotestis not examined because of disintegration in apical
viscera. Hermaphroditic duct (fig. 171f, g, GD) very long and
slender, anterior half slightly swollen, then tapering down to union
with carrefour after a sharply angled turn. Albumen gland (GG) very
flat and narrow, elongated, only one or two acinal layers thick.
Talon (GT) long, with slender shaft and gradually swollen head that
is grossly expanded at tip. Carrefour (X) moderately expanded,
receiving hermaphroditic duct laterally, expanding to enter prostate-
uterus. Prostate (DG) of two or three rows of acini that are about
one-third as wide as they are long, opening into a narrow tube.
Uterus (UT) bipartite, lower chamber two-thirds length of upper
with much thicker and more glandularized walls.
Vas deferens (VD) typical, entering penis about 0.5 mm. below
apex. Penial retractor (PR) originating from diaphragm, inserting
directly on head of penis. Penis (fig. 171h, P) about 3.9-4.1 mm.
long, quite slender, very slightly tapering apically, internally with
two pilasters (PP). both higher than wide, tending to weakly split or
be very slender apically. generally fading out near atrium. Atrium
(Y) short, not so wide as in other dissected Libera.
Free oviduct distinctly longer than prostate, tapering gradually
until at midpoint no wider than vas deferens, no further narrowing.
Spermatheca with typical head, shaft inserting directly on peni-
oviducal angle.
Free muscle system without unusual features.
(Based on BPBM 145287, one whole adult 4.08 mm. in diameter,
with 65/8 whorls and 107 ribs on the body whorl, plus several
extracted fragmentary specimens.)
Libera bursatella (Gould, 1846)
Abundant material of this species was obtained by
the Mangarevan Expedition on both Mt. Aorai and
Mt. Orofena above 4,000 ft. elevation. On Mt. Aorai it
was associated with L. cookeana and L. micrasoma;
on Mt. Orofena with L. umbilicata. L. bursatella was
overwhelmingly dominant, with 417 specimens to only
29 of the other three. L. umbilicata is recognizable by
its minute size (mean diameter 3.71 mm.), few ribs (26-
32) and in having the parietals of equal length. L.
micrasoma has the 2 parietals of equal length, much
more prominent sculpture, and generally is 0.5 mm.
less in diameter at similar whorl counts (table CI). L.
cookeana is much larger (mean diameter 7.60 mm.),
with more widely spaced radial ribs (ribs/mm. 3.72),
and has a third palatal trace. In contrast, L. bursatella
has the 2nd parietal deeply recessed, possesses rather
low sculpture that is more closely spaced, 6.12-12.02
ribs/mm., and is of intermediate size (adult diameter
4.64-5.88 mm.) (table C). Only the Moorean L.
recedens and L. gregaria appear similar in sculpture,
but these species have a large columellar and 3 palatal
barriers, while L. bursatella lacks the columellar and
normally has only 2 palatals.
Differences between the Mt. Aorai and Mt.
Orofena populations are confined to ribbing, with the
former having 98-161 (mean 119.0) ribs on the body
whorl and a spacing of 6.12-8.95 (mean 7.14) ribs/mm,
and the latter 158-185 (mean 171.8) ribs on the body
whorl with a spacing of 8.68-12.02 (mean 10.44)
ribs/mm., and also early whorl diameter (table CI ). In
the Mt. Aorai shells there are generally three to six
microradial riblets between each major pair; in the Mt.
Orofena shells two to four microradials (fig. 174c, d).
The disparity in quantities collected, 40 from Mt.
Orofena and 378 from Mt. Aorai, is sufficient to make
the small mean size difference (0.22) probably an
artifact of sampling rather than having any biological
significance. The slight mean difference in H/D ratio
(0.023) is equally insignificant, particularly when
compared with the large differences between popu-
lations of the Mt. Aorai bursatella (table CII).
Unlike the situation in the Mangarevan Anceyo-
donta obesa (p. 203), where rib counts remain constant
despite significant size changes, or in the Rapan
Opanara areaensis, Orangia cookei, Rhysoconcha,
and Ruatara oparica, where changes in both size and
TABLE CI. - EARLY WHORL DIAMETER IN LIBERA
Name
microsoma
bursatella otofenensis
bursatella bursatella
Number of
Specimens
Examined
gregaria
3WD 4WD 5WD
1.23i0.013 1.62*0.013 2.03*0.022
(1.19-1.26) (1.59-1.66) (1.92-2.06)
1.21i0.022 1.61*0.031 2.04*0.033
(1.13-1.29) (1.49-1.72) (1.92-2.15)
1.41i0.041 1.88*0.052 2.31*0.065
(1.32-1.52) (1.76-2.02) (2.19-2.58)
1.42*0.013 1.96*0.018 2.59*0.035
(1.39-1.46) (1.92-2.02) (2.48-2.72)
1.14*0.011 1.56*0.014 2.07*0.017
(1.12-1.18) (1.51-1.61) (2.01-2.11)
1.22*0.015 1.70*0.024 2.36*0.024
(1.18-1.28) (1.64-1.81) (2.30-2.47)
394
SOLEM: ENDODONTOID LAND SNAILS
rib count are correlated, Libera bursatella shows a
change in rib count and spacing that is independent of
size and shape. This is recognized as a subspecific
difference, with the nominate race, L. bursatella
bursatella, restricted to Mt. Aorai, and a new race, L.
b. orofenensis, found on Mt. Orofena. No intermediate
examples were seen. Since localized collections of each
form were taken from single transects on each
mountain, the possibility of clinal variation remains to
be investigated. I would not be at all surprised to find
that sampling of spatially intermediate areas would
provide morphologically intermediate populations.
This is suggested by the rib counts and rib spacing
found in the unlocalized BMNH set (table CII), which
contained specimens with 117, 117, 135, and 161 ribs. It
has been classified as typical bursatella on the basis of
rib spacing (ribs/mm. 6.63, 6.78, 7.55, and 8.91,
respectively). The specimens are large (mean diameter
5.64 mm.) and this is the only material that came close
to spanning the gap in rib counts between the
Mangarevan Expedition L. b. bursatella (98-137) and
L. b. orofenensis (158-185).
Libera bursatella bursatella (Gould, 1846).
ures 171a-e; 174a-c.
Fig-
Helix bursatella Gould, 1846, Proc. Boston Soc. Nat. Hist., 2, p.
175 — Tahiti and Eimeo (= Moorea), Society Islands (partly);
Gould, 1852, U. S. Explor. Exped. Wilkes, 12, pp. 51-53 - "2,000-
5,000 ft. elevation," Tahiti and Eimeo (partly); Gould, 1860,
Atlas of Shells, U. S. Explor. Exped., Wilkes, pi. 4, figs. 52f, g, h,
i — not other cited figures except possibly k, 1, m (juvenile).
Libera bursatella (Gould), Ponsonby, 1910, Proc. Malacol. Soc.
London, 9, (1), pp. 39-40 (partly).
Diagnosis. — Shell slightly smaller than average, diameter 4.64-
5.88 mm. (mean 5.39 mm.), with 6-8 normally coiled whorls. Apex
usually slightly elevated, occasionally flat, whorls of spire descending
progressively more rapidly, body whorl usually descending slightly
more rapidly, H/D ratio 0.482-0.694 (mean 0.576). Umbilicus
secondarily narrowed to form brood chamber by gradual inward
growth of baso-columellar margin, which becomes acutely angled at
adulthood, opening generally circular to siibcircular, at adult size
contained 3.38-6.16 times (mean 4.57) in the diameter. Postnuclear
whorls with prominent, crowded, strongly protractively sinuated
radial ribs, 98-161 (mean 119.0) on the body whorl, whose interstices
are 1-3 times their width. Microsculpture of fine radial riblets, three
to six between each pair of major ribs, with exceedingly fine and
crowded spiral riblets, visible only under 96 X magnification.
Secondary sculpture of low and broadly rounded, quite crowded
spiral cords that are most prominent on shell base and generally
absent near periphery. Sutures impressed, whorls flatly rounded
down to periphery, which varies from obtusely rounded to obtusely
angulated or even slightly protruded (rarely), lower palatal margin
evenly rounded, basal margin generally flatly rounded to a weak to
prominent sulcus just before a sharply angled baso-columellar
margin. Aperture ovate, flatly rounded above and below variable
periphery, columellar walls strongly sinuated, inclined about 25°
from shell axis. Parietal barriers 2, extending posteriorly slightly less
than one-quarter whorl: upper moderately elevated, bladelike,
slightly expanded and serrated above on posterior third, with very
gradual anterior descension; 2nd equal in height to upper posteriorly,
deeply recessed, with gradual anterior descension, only one-half
length of upper parietal. Columellar wall with broad callus, more
strongly rounded and convex posteriorly, but without a barrier.
Palatal barriers normally 2, sometimes only 1 (5.1 per cent) or absent
(5.1 per cent), subperipheral. extending posteriorly about one-eighth
whorl, deeply recessed: lower smaller and shorter than upper,
elevated and bladelike, with gradual anterior descension; 2nd slightly
higher, longer, with more gradual anterior descension, more clearly
expanded above.
The nominate race of Libera bursatella differs
from the subspecies orofenensis primarily in its more
widely spaced radial ribbing, with L. bursatella
bursatella averaging about 119 ribs and L. bursatella
orofenensis about 172 ribs. Specimens of L. cookeana
are quite similar in general effect, but are immediately
separable by their much larger size (mean diameter
7.60 mm.), possession of a supraperipheral palatal
trace, and much more widely spaced radial ribbing. L.
micrasoma has the parietal barriers of equal length
and is much smaller (mean diameter 4.46 mm.). The
two Moorean species with relatively regular and
normal ribbing, L. recedens and L. gregaria, differ
immediately in having a prominent columellar barrier,
very fine radial ribbing (mean rib count about 178),
and a prominent 3rd palatal.
Description. — Shell of less than average size, with slightly more
than 7 moderately tightly coiled whorls. Apex and early spire
flattened, lower whorls descending progressively more rapidly, last
whorl only slightly deflected, H/D ratio 0.602. Embryonic whorls 1%,
sculpture partially eroded, remnants consisting of fairly small,
broadly rounded radial ribs with one or two riblets between.
Remaining whorls with moderately low and broadly V-shaped,
protractively sinuated radial ribs, 98 on the body whorl, whose
interstices are 1-3 times their width. Microsculpture (fig. 174c) of
numerous fine radial riblets, very fine spiral riblets, and low
secondary spiral cords that become more prominent on shell base.
Sutures shallow, whorls slightly rounded above weak supraperipheral
sulcus, periphery obtusely angulated, more strongly rounded below
periphery, somewhat flattened with a slight sulcus at umbilical
margin. Umbilicus secondarily constricted by inward growth of baso-
columellar margin, opening nearly circular, contained 4.50 times in
the diameter. Color yellowish-white with zigzag flammulations on
spire and body whorl, becoming weaker below periphery. Aperture
subquadrangular, with flat columellar margin and gently rounded
palatal margins, inclined about 25° from shell axis. Parietal barriers
2, extending about one-quarter whorl: upper lamellate for entire
length, higher posteriorly; lower recessed and only half length of
upper, slightly more elevated at posterior end. Columellar wall with
slight callus, but no barriers. Palatal wall with 2 deeply recessed,
short, low, lamellate ridges, situated below periphery. Height of
neotype 3.07 mm., diameter 5.10 mm.
Neotype. - Society Islands: Tahiti, Station 863,
Mt. Aorai trail at 4,700-5,500 ft. elevation. Collected by
E. Zimmerman, Y. Kondo, and D. Anderson on
September 14, 1934. BPBM 142059.
Range. — Slopes of Mt. Aorai from 4,700 ft.
probably to summit, Tahiti, Society Islands.
Material. — Tahiti (6 specimens, BMNH
84.11.20.3-8): Aorai trail (Station 863) at 4,700-5,500 ft.
elevation (169 specimens, BPBM 142058-70, BPBM
145911); Aorai trail (Station 864) at 5,500-5,600 ft.
elevation (35 specimens, BPBM 145219-24); Aorai trail
(Station 865) at 5,600-6,300 ft. elevation (62 specimens,
BPBM 145280-6, BPBM 145290-2, BPBM 145926);
valley west of Aorai trail (Station 866) at 6,000 ft.
elevation (90 specimens, BPBM 145293-300); Aorai
SYSTEMATIC REVIEW
395
TABLE CII. - LOCAL VARIATION IN MANGAREVAH EXPEDITION LIBERA
Number of
Specimens
bursatella burtatella
BMNH84.11.20.3-8
BPBM 142059 (adult)
Sta. 863 (4700-5500')
BPBM 142058-9,
BPBM 142066-7 (gerontic)
Sta. 863 (4700-5500')
BPBM 145219 (adult)
Sta. 864(5500-5600')
BPBM 145290 (light color phase)
Sta. 865 (5600-63001)
BPBM 145280-1 (adults)
Sta. 865(5600-6300')
BPBM 145392 (gerontic)
Sta. 866 (6000')
bursatella orofenensis
24
11
16
BPBM 145587
Sta. 946 (5500-57001)
BPBM 145811, -6-8
Sta. 949 (4500')
mlcrasoma
BPBM 145287-8
Sta. 865 (5600-6300')
BPBM 145393
Sta. 866 (6000')
umbillcata
BPBM 145820
Sta. 949(4500')
cookeana
Sta. 863-65 (4700-6300')
5
6
10
6
Height
3.01±0.096
(2.81-3.27)
2. 98±0.034
(2.61-3.27)
3.24±0.099
(2.88-3.86)
3.26±0.103
(3.03-3.62)
2. 97±0.091
(2.76-3.36)
2.76±0.061
(2.56-3.22)
2.71±0.089
(2.43-3.03)
2.50±0.108
(2.29-2.75)
4.01*0.161
(3.53-4.51)
Diameter
5.64±0.056
(5.49-5.75)
5.43*0.030
(5.10-5.69)
5. 60±0.074
(4.97-5.88)
H/D Ratio
5.11±0.068
(4.93-5.26)
5.37±0.091
(5.00-5.59)
4. 57±0.033
(4.47-4.74)
4. 34±0.045
(4.14-4.41)
3.71*0.031
(3.66-3.79)
7.60±0.146
(7.19-8.17)
0.639±0.0023
0.624±0.0181
(0.570-0.686)
Whorls
0.533±0.0125 61/2-
(0.512-0.568) (61/4-61/2)
0.548*0.0063 61/2
(0.494-0.602) (61/4-65/8)
0.578*0.0172 63/4+
(0. 500-0. 678) (6 1/4-7 5/8)
2.97*0.043
(2.89-3.16)
5.49*0.056
(5.39-5.72)
0.541*0.0093
(0.518-0.585)
6 1/4+
(6-6 1/2)
2.83*0.093
(2.63-2.96)
5.53*0.075
(5.33-5.79)
0.505*0.0091
(0.482-0.536)
6 1/8+
(6-61/2)
3.19*0.071
(2.75-3.53)
5.10*0.080
(4.64-5.75)
0.624*0.0090
(0.557-0.694)
7 3/8-
(6 5/8-8)
3.37*0.089
(3.01-3.66)
5.42*0.030
(5.29-5.49)
0.622*0.0147
(0.561-0.666}
7 1/2-
(7 1/8-8)
7 1/8-
(0.588-0.688) (63/4-73/4)
0.553*0.0147 65/8
(0.512-0.600) (63/8-7)
0.605*0.0120 67/8
(0.550-0.681) (61/2-71/2)
6 1/2+
(6 1/4-7)
0.673*0.0250 67/8+
(0.625-0.736) (61/2-71/2)
0.528*0.0208 71/4-
(0.467-0. 600) (6 3/4-7 1/2)
D/U Ratio
6.18*0.210
(5.80-6.77)
4.69*0.086
(3.65-5.60)
4.83*0.088
(3.62-5.87)
4.89*0.153
(4.56-5.53)
4.46*0.332
(3.68-5.60)
4.07*0.133
(3.38-5.00)
4.11*0.144
(3.56-4.67)
3.74*0.136
(3.30-4.00)
4.72*0.297
(3.30-5.33)
3.62*0.176
(2. 96-4. 80)
3.73*0.166
(3.42-4.47)
3.16*0.125
(2.94-3.41)
3.92*0.339
(3.03-5.00)
trail (Stations 869, 870) at 5,000 ft. elevation (10
specimens, BPBM 145490, BPBM 145532-5); Aorai
trail (Station 867) at 4,700-6,300 ft. elevation (11
specimens, BPBM 145694-700); Mt. Aorai at 2,235 (?)
m. (=7,360 ft.) elevation1. (1 specimen, FMNH 41007
collected by John N. Dixon on June 19, 1946).
Remarks. — The name Helix bursatella Gould,
1846, has been interpreted differently by each sub-
sequent writer. The story of how the Wilkes shells
became mixed is well known (see Johnson, 1964, pp.
10-11). Gould's description and figures represent
several species. The Wilkes' collections were made
between 2,000 and 5,000 ft. elevation (Gould, 1852, p.
53). Material studied by Garrett (1884) and other
authors presumably came from the same or lower
zones. Several specimens in museum collections
(USNM 5452, USNM 20913-20919, MCZ 169066, MCZ
216751) are labelled as Helix bursatella and are
presumed to be part of the Wilkes material. None of
the specimens exactly match the type figures. The sets
contain a mixture of at least four species, mostly
represented by worn, partially fungus-eaten examples.
Under these circumstances it was thought best to
1 Since the elevation of Mt. Aorai is given as 7,321 ft.. I doubt the
accuracy of this elevation.
select a neotype that matches Gould's figures of the
typical form and at the same time fix a precise type
locality. Gould (1860, pi. 4, figs. 52, a-m) figured, under
the name Helix bursatella, specimens of the form
discussed here (figs, f-i, and probably k-m), L.
streptaxon (figs, b-e) and L. incognata (fig. 52, a).
Figures 52, f-i, which Gould stated in the plate ex-
planations to be the "typical form," compare exactly
with some of the material collected on Mt. Aorai.
Gould's figured shell shows 94 ribs on the body whorl.
This is so near the range shown by Mt. Aorai shells
that I have no hesitation in designating Gould's figures
f-i as representing bursatella, and in selecting a
neotype (BPBM 142059 from Station 863, Mt. Aorai
trail between 4,700 and 5,500 ft. elevation) to match
these figures.
The possibility exists that two species are
confused under this name. Dissection of material from
Station 866 (the whole specimens had a much sharper
peripheral angulation than in the type), produced a
penis length of 4.3-4.5 mm. Dissection of specimens
from Station 863 (BPBM 142059) showed three whole
specimens that agreed with the type in peripheral
angulation had penial lengths of 5.0-6.7 mm.; two of
three fragmentary extracted specimens had penial
VD
PP
PP
GG
HG
FIG. 171. Anatomy of Libera; a-e, Libera bursatella bursatella. Station 866, Mt. Aorai, Tahiti, Society Islands. BPBM 145394. a,
genitalia, b, interior of penis, c, interior of penis, d, apical portion of pallial region, e, anterior portion of pallial region; f-h, Libera micrasoma.
Station 865, Mt. Aorai, Tahiti, Society Islands. BPBM 145287. /, genitalia without penial region, g, detail of carrefour region, h, interior of
penis. Scale lines equal 1 mm.
396
SYSTEMATIC REVIEW
397
lengths of 5.1 and 7.0 mm.; and a third fragmentary
example had a penis length of only 3.4 mm. (fig. 171c).
No basic pilaster differences were noted.
Review of synoptic shell material indicated a
partial dimorphism, with one form having an obtusely
angulated periphery, the other being much more
sharply angulated and occasionally acutely angulated
at the periphery. Measurements of shells from the
Mangarevan Expedition also produced discordant data.
Specimens from Station 865 (BPBM 145392) that had
been sorted out as "gerontic" at the Bishop Museum
and "adult" examples from Station 865 (BPBM
145280-1) were proportionately much higher and with
larger whorl counts (table CII) than the "light color
phase" adults from Station 865 (BPBM 145290) or
material from Stations 863 and 864. Since pill box
capacity is limited and there were many specimens
from the stations involved — Station 863 (169
specimens), Station 864 (35 specimens), Station 865 (62
specimens), and Station 866 (90 specimens) — these
differences may partly reflect size bias introduced
during sorting activities in the middle 1930's. I did not
have enough material on loan or sufficient unextracted
soft parts to see whether the penial and peripheral
variations are correlated. Possibly there is sufficient
material in the Bishop Museum to determine whether
variation or sibling species are involved, but this will
have to be investigated by others. Tentatively, I am
treating the Mt. Aorai populations as one species. A
similar dimorphism appears to be present in the Mt.
Orofena populations (see below).
Some confusion of very young Libera b. bursatella
and Mautodontha aoraiensis existed, since at least one
specimen of the latter was located in a set (BPBM
142065) of "ananeanic" Libera bursatella. The two
species are readily distinguished by the smaller nuclear
whorls, narrower umbilicus, more ovate whorl contour,
absence of palatal dentition, and absence of secondary
spiral cording in the Mautodontha. The juvenile
Libera have the body whorl laterally compressed,
there is at least one palatal trace and the 2 parietals
are more widely spaced and proportionately much
lower.
Description of soft parts. — Foot truncated anteriorly, slightly
tapering to tail, which is bluntly rounded behind. Sole undivided.
Pedal grooves relatively low on foot, pedal much more prominent
than suprapedal. Slime network prominent on sides of body and
above tail. Head projecting in front of foot. Ommatophores partly
retracted in all material, typical in eyespot size and color. Gonopore
located just above foot margin, behind right rhinophore and just
below right ommatophore.
Body color yellow-white, without darker markings.
Mantle collar (MC( very narrow, a prominent glandular
extension onto mantle roof (fig. 171e). Pneumostomal opening
narrow, without any mantle lobes or laps. Anus (A) with typical
slanted opening just inside pneumostome.
Pallial region (fig. 171d, e) extending V/i - l'/2 whorls apically.
Lung roof clear, without granulations. Kidney (K) about 3.6 mm.
long, rectal arm about 2.04 mm. long, laterally compressed with a
slight turnover producing a narrow pocket in which the ureter opens.
Ureter (KD) starting at apex of kidney, reflexed along rectal arm of
kidney, opening next to hindgut just inside kidney foldover. Heart
(H) about 1.45 mm. long, lying parallel to hindgut. Principal
pulmonary vein (HV) slender, fusing with heavy glandular extension
of mantle collar. Hindgut (HG) typical, extending slightly less than
one-quarter whorl above apex of pallial cavity before deflecting into
intestinal loops.
Ovotestis of palmately clavate alveoli, occupying one-half whorl
above stomach apex, buried in albumen gland and angled as in
Endodonta (fig. 163c). Hermaphroditic duct (fig. 171a, GD) very
long, slender apically, medially swollen, continuing to about 0.67
mm. before junction with carrefour (X) where it narrows and
becomes transparent. Albumen gland (GG) long and slender, broader
basally. Talon (GT) elongated and slender with gradually bulbous
head, carrefour (X) only slightly swollen, hidden by acini of albumen
gland. Prostate (DG) with two or three rows of short acini opening
into a narrow duct that continues past end of prostate as vas
deferens. Uterus (UT) bipartite, upper half slenderer and with less
glandular walls than in lower half, which extends beyond end of
prostate.
Vas deferens (VD) lightly bound to penioviducal angle, passing
up along penis, entering penis laterally about 0.2 mm. below apex
between pilasters. Penial retractor (PR) arising from diaphragm at
apex of pallial cavity, inserting directly onto head of penis. Penis (P)
about 4.3-4.5 mm. long, slightly tapered at apex, irregularly swollen
medially and near base, internally with two pilasters, high and
complexly folded (fig. 171b, PP), one larger than other, not extending
into atrium. Atrium (Y) short and rather wide.
Free oviduct (UV) much longer than prostate, very slender, no
larger in diameter than vas deferens. Spermatheca (S) with ovately
expanded head lying above pallial cavity along surface of albumen
gland, slender shaft narrower than vas deferens and free oviduct,
inserting directly onto penioviducal angle. Vagina absent.
Free muscle system very elongated, but without structural
peculiarities. Right ommatophoral retractor passing through pen-
ioviducal angle, uniting with right rhinophoral retractor just
posteriorly of buccal mass. Tentacular retractors unite with tail fan
slightly more than one-third of way to apex of columellar muscle.
Buccal mass elongatelv oval, with very slender generative sac.
Buccal retractors not split, inserting on posterior margin of buccal
mass, joining tail fan laterally about 5 mm. below columellar muscle
apex. Stomach extending from one-quarter whorl above apex of
pallial cavity for 1'i whorls, early expansion occupying one-eighth
whorl. Intestinal looping typical, occupying one-quarter whorl.
Digestive glands extending four whorls above ovotestis to
nuclear whorls in preserved adults. Salivary glands lying lateral to
esophagus, weakly joined posteriorly above.
(Based on BPBM 145394, whole individual 5.26 mm. in diameter
with 7%+ whorls and several extracted examples.)
Libera bursatella orofenensis, new subspecies.
Figure 174d-f.
Diagnosis. — Shell smaller than average, diameter 4.71-5.56 mm.
(mean 5.17 mm.), with 6%-7'4 normally coiled whorls. Apex barely
protruding or rarely flat, whorls of spire descending progressively
more rapidly, last whorl not descending more rapidly, H/D ratio
0.512-0.688 (mean 0.599). Umbilicus secondarily narrowed to form
brood chamber by regular and gradual inward extension of baso-
columellar margin, opening in adult circular to subcircular, contain-
ed 3.30-5.33 times (mean 4.15) in the diameter. Postnuclear whorls
with prominent, crowded, somewhat finer than in nominate
subspecies, strongly protractively sinuated radial ribs, 158-185 (mean
171.8) on the body whorl, whose interstices are 1-2 times their width.
Microsculpture of rather prominent radial riblets, two to four
between each pair of major ribs, crossed by exceedingly fine and
crowded spiral riblets that are barely visible under 96 X mag-
nification. Secondary sculpture of low and broadly rounded, quite
398
SOLEM: ENDODONTOID LAND SNAILS
crowded spiral cords, that are most prominent on shell base. Sutures
impressed, whorls flatly rounded down to obtusely rounded or
angulated periphery, lower palatal and basal margins flatly rounded
down to acutely angled and strongly protruded baso-columellar
margin, with a distinct sulcus outside the angulation. Aperture
subovate, flatly rounded above and below obtusely rounded or
angulated periphery, inclined about 25° from shell axis. Parietal
barriers 2, extending posteriorly slightly less than one-quarter whorl,
sometimes (6.3 per cent) with lower one absent: upper low and
bladelike, very weakly expanded above on posterior third, with very
gradual anterior descension; 2nd equal in height to upper posteriorly,
deeply recessed, equal to about half the length of upper. Columellar
wall flatly rounded and convex internally, without barriers. Palatal
wall normally with 2 barriers, frequently (25 per cent) with only 1
present, occasionally with a 3rd palatal (6.3 per cent) or with all
palatals absent (6.3 per cent): both palatals subperipheral, low and
bladelike, very weakly expanded above, with gradual anterior
descension, moderately deeply recessed within aperture.
The more numerous radial ribs (158-185) of Libera
bursatella orofenensis immediately separate it from
Libera bursatella bursatella with only 98-161 major
radial ribs. The Moorean species, L. recedens and L.
gregaria, have similar ribbing counts, but both have a
prominent columellar barrier. The very small Libera
umbilicata from Mt. Orofena has the parietals of equal
length and less than 35 major ribs, whose interstices
are 6-9 times their width.
Description. — Shell of less than average size, with 7'/4 normally
coiled whorls. Apex and early spire somewhat flattened, lower whorls
descending progressively more rapidly, H/D ratio 0.608. Embryonic
whorls 1%, sculpture of larger radials with two fine riblets between
each pair, and extremely close-set and very faint microspirals.
Postnuclear whorls with prominent, narrow, relatively crowded,
strongly protractively sinuated radial ribs, 158 on the body whorl,
whose interstices are less than twice their width. Microsculpture of
relatively prominent radial riblets, two to four between each pair of
major ribs, with barely visible and extremely crowded microspirals.
Secondary microsculpture of low, broadly rounded spiral cords that
are most prominent on shell base. Sutures impressed, whorls evenly
and gently rounded down to obtusely angled periphery, with lower
palatal and basal margin gently and evenly rounded to inwardly
protruded and sharply angled baso-columellar margin. Color light
yellow horn, with prominent, broad, somewhat irregular, reddish
flammulations. Umbilicus typically narrowed to form brood cham-
ber, opening circular, contained 3.95 times in the diameter. Aperture
subovate, gently rounded above and below obtusely angled pe-
riphery, inclined about 25° from shell axis. Parietal barriers 2,
extending posteriorly almost one-quarter whorl: upper moderately
elevated, very slender, weakly expanded on posterior third, with
gradual anterior descension; 2nd equal in height posteriorly to upper,
slightly more than half length of upper, deeply recessed within
aperture. Columellar wall convex internally with a moderate callus,
without barriers. Palatal barriers 2, rather deeply recessed, extending
posteriorly about one-eighth whorl: both elevated and bladelike with
gradual anterior descension. Height of holotype 3.14 mm., diameter
5.17 mm.
Holotype. — Society Islands: Tahiti, Station 945,
south ridge of Mt. Orofena at 5,700-6,600 ft. elevation.
Collected by Harold St. John and Raymond Fosberg
on September 25, 1934. BPBM 145574.
Range. — Upper Papenoo Valley and Mt. Orofena
at 4,000-6,000 ft. elevation, Tahiti, Society Islands.
Paratypes. — Same as list of material.
Material. — Tahiti: east end of south ridge, Mt.
Orofena (Stations 949, 956) at 4,500 ft. elevation (19
specimens, BPBM 145653, BPBM 145811-9); south
ridge of Mt. Orofena (Stations 944-6) at 5,000-6,600 ft.
elevation (17 specimens, BPBM 142351-2, BPBM
145574-5, BPBM 145587-90); Papenoo Valley (Station
952) at 4,000 ft. elevation (1 specimen, BPBM 145625);
ridge of Papenoo Valley (Station 954) at 5,200-5,500 ft.
elevation (3 specimens, BPBM 145844-6).
Remarks. — The figured paratype of Libera
bursatella orofenensis is exceptionally elevated and
has the periphery less angulated than usual. It does
illustrate the sculptural difference from the nominate
race very well. Mean size and shape differences (table
C) from L. b. bursatella are insignificant, particularly
when the large interpopulational variation (table CII)
is noted. Only in regard to early whorl diameter is
there a distinct difference (table CI), with the
nominate race being larger.
Only 40 orofenensis (16 adult) were collected,
compared with 384 bursatella (74 adult). The shift in
quantity and percentage of adults results from
collecting bias. The Mangarevan Expedition botanists,
H. St. John and R. Fosberg, who made the collections
of L. b. orofenensis, could be expected to collect fewer
juveniles and a smaller total quantity than would the
malacological assistants, Anderson and Kondo, who
collected L. b. bursatella. Hence the 40 per cent adult
ratio in orofenensis probably is considerably inflated
by collecting bias and the 19.3 per cent ratio in L. b.
bursatella would be more accurate.
Differences between the two populations with
several adults, (table CII), Stations 946 and 949, are
marked and statistically significant. With 9 df, "t" =
2.1520 for height, 2.260 for diameter, and 3.8075 for
H/D ratio. The differences are the same order of
magnitude as those found between the nominate race
populations discussed above. The differences probably
are not age connected. The specimens with lower
whorl count have a distinctly narrower umbilicus and
hence are nearer to full adulthood, while the speci-
mens with higher whorl count have a wider umbilicus
and were less adult in their growth characters. The
smaller diameter of the latter is caused by their
greater height and change in coiling pattern.
The only sympatric species, L. umbilicata, is
immediately separable by its very widely spaced radial
sculpture, much smaller size (mean diameter 3.71
mm.), and in having the 2 parietal barriers equal in
length. The Moorean Libera recedens and L. gregaria
have very similar sculpture, but are much larger, more
depressed, have a prominent columellar barrier and 3
palatals.
Description of soft parts. — Only broken extracted specimens
were available for study. Preservation was poor and no illustrations
were prepared. The penis was short, 2.5-3.3 mm. long in three
examples, but had the same pilaster pattern seen in the nominate
subspecies. Whether the size difference is a factor of age or
systematically important is uncertain.
(Based on BPBM 145584, four partial examples.)
GT
GG
VD
FIG. 172. Anatomy of Libera: a-b, Libem cookeana. Station 865, Mt. Aorai, Tahiti, Society Islands. BPBM 145289. a, interior of
penis, b, lateral view of raised pilaster; c-g, Libera fratercula rarotongensis. Station 6, 2 miles east of Avarua, Rarotonga, Cook Islands.
FMNH 144556. c, /, genitalia (angle of ovotestis incorrect ), d, interior of penis, e, pallia! region, g, egg. Scale lines equal 1 mm.
399
400
SOLEM: ENDODONTOID LAND SNAILS
Libera cookeana, new species. Figures 172a, b;
173a, b.
Diagnosis. — Shell very large, diameter 7.19-8.17 mm. (mean 7.60
mm.), with 6%-7'/2 normally coiled whorls. Apex and early spire
slightly elevated, whorls of lower spire descending progressively more
rapidly, body whorl distinctly deflected below periphery of pen-
ultimate whorl, H/D ratio 0.467-0.577 (mean 0.528). Umbilicus
secondarily narrowed to form brood chamber by gradual inward
expansion of sharply angled baso-columellar margin, opening in
adult subcircular, contained 3.03-5.00 times (mean 3.92) in the
diameter. Postnuclear whorls with rather low, prominent, strongly
protractively sinuated radial ribs, 85-95 (mean 91.4) on the body
whorl, whose interstices are 2-3 times their width. Occasional traces
of typical microradial ribbing remaining, but all specimens with
sculpture worn and only slight traces of any sculpture below
periphery of body whorl. Sutures deep, whorls rather strongly
rounded down to very obtusely angulated periphery, lower palatal
and basal margins more gently and evenly rounded down to distinct
sulcus before baso-columellar angulation. Aperture subovate, more
strongly rounded above than below periphery, inclined about 30 - 35°
from shell axis. Parietal barriers 2, extending posteriorly almost one-
quarter whorl: upper rather sharply elevated and weakly expanded
on posterior quarter, moderately abrupt descension to raised ridge-
like anterior two-thirds; lower with posterior portion equal in height
and length to upper, anterior segment absent or retained (one of six
specimens) as a vague threadlike trace. Columellar wall with a low,
deeply recessed, very broad and rounded barrier, visible only by
extreme tilting of aperture. Palatal barriers 3, moderately deeply
recessed, extending posteriorly less than one-eighth whorl: lower 2
subperipheral, quite elevated, thin and slender, only weakly
expanded above, upper less flattened above and with more gradual
anterior descension; 3rd supraperipheral, a short, low inconspicuous
threadlike trace.
The much larger adult size without any increase
in whorl count, more widely spaced radial ribbing,
distinct columellar barrier, and presence of a 3rd
palatal immediately separate Libera cookeana from
the sympatric L. bursatella bursatella. The only other
Society Islands species of similar size, L. incognata,
differs in its greatly reduced ribbing (43-55 major ribs),
proportionately higher spire (mean H/D ratio 0.650),
and generally higher whorl count.
Description. — Shell very large, with 7'/2 normally coiled whorls.
Apex slightly protruding, lower whorls of spire descending progres-
sively more rapidly, body whorl deflected below level of penultimate
whorl periphery, H/D ratio 0.577. Apical sculpture and sculpture on
early spire completely eroded, sculpture visible in umbilicus as
typical radial ribbing. Postnuclear whorls with prominent, broadly
rounded, rather widely spaced radial ribs, 91 on the body whorl,
whose interstices are 2-4 times their width. Surface worn, but
microsculpture occasionally visible as five to eight relatively large
riblets between each pair of major ribs, with very occasional traces of
secondary spiral cording. Surface too worn to detect status of any
spiral microsculpture. All traces of color leached from shell.
Umbilicus secondarily narrowed to form brood chamber by inward
growth of baso-columellar margin, last whorl at aperture showing
evidence of parietal wall detachment, opening subcircular except for
detachment area, contained 3.87 times in the diameter. Aperture
subovate, gently rounded above and below obtusely angled pe-
riphery, inclined about 30° from shell axis. Parietal barriers 2,
extending posteriorly almost one-quarter whorl: upper high and
bladelike, distinctly more highly elevated on posterior quarter,
anterior half a low, raised lamellar ridge; 2nd parietal deeply
recessed, equal in height and with same shape as elevated posterior
portion of upper parietal, about half the length of upper parietal.
Columellar wall with single low and broadly rounded lamellar trace,
visible clearly only by extreme tilting of aperture. Palatal barriers 3.
deeply recessed within aperture, extending posteriorly more than
one-eighth whorl: lower 2 subperipheral, high and bladelike, 2nd
slightly higher, flattened on top, with progressively more gradual
anterior descension; 3rd a weak, supraperipheral, short, very deeply
recessed threadlike trace. Height of holotype 4.38 mm., diameter 7.68
mm.
Holotype. — Society Islands: Tahiti, Station 865,
Mt. Aorai, near top of trail at 5,600-6,300 ft. elevation.
Collected by E. Zimmerman, Y. Kondo, and D.
Anderson on September 15, 1934. BPBM 145289.
Range. - Mt. Aorai at 4,700-6,300 ft. elevation,
Tahiti, Society Islands.
Paratypes. — Same as list of material.
Material. — Tahiti: near top of Mt. Aorai trail
(Station 865) at 5,600-6,300 ft. elevation (3 specimens,
BPBM 145289, BPBM 145924-5); Mt. Aorai (Station
863) at 4,700-5,500 ft. elevation (1 specimen, BPBM
145912); Mt. Aorai (Station 864) at 5,500-5,600 ft.
elevation (2 specimens, BPBM 145922).
Remarks. — Scattered individuals of this species
were taken at stations where Libera bursatella
bursatella was common to abundant. At first glance,
L. cookeana would be taken for a gerontic specimen of
that species. The gap between the largest L. bursatella
(diameter 5.88 mm.) and the smallest L. cookeana
(diameter 7.19 mm.) is substantial. In addition, L.
cookeana has a distinct columellar barrier, a 3rd
palatal, with less frequent and much more widely
spaced radial ribs (ribs/mm. 3.52-3.84 in cookeana;
6.12-8.95 in bursatella). The early whorl diameter in L.
cookeana (table CI) is identical at three whorls, but
diverges rapidly at five whorls and beyond. Juvenile
specimens of the two species might be difficult to
separate except by rib counts and spacing. No
juveniles of L. cookeana were available, but a few
juvenile L. bursatella had a 3rd palatal present so that
this character cannot be relied upon for separation.
Species with occasional huge gerontic individuals,
such as Minidonta simulata (fig. 70d), have the larger
shells with greatly reduced apertural barriers; hence,
the presence of a columellar and one additional palatal
in these specimens, compared with L. bursatella,
greatly lowers the possibility that they are gerontic
shells. In addition, the penial pilaster of L. cookeana
(fig. 172a, b) is quite different from that found in L.
bursatella (fig. 171b, c), its grossly unequal pilasters
contrasting strongly with the subequal pilasters in the
latter.
Description of soft parts. — Foot and tail typical, slightly
tapering and bluntly rounded posteriorly. Sole undivided. Pedal
grooves prominent, rather high on foot. Head and ommatophores
typical. Gonopore in normal position.
Body color yellow-white, without darker markings.
Mantle collar thicker than in L. bursatella, without glandular
extension onto pallial roof.
Pallial region about 14 mm. long. Lung roof clear, without
granulations. Kidney with very vague outline, poorly preserved.
Ureter typical. Heart very small, proportionately. Principal pul-
monary vein a narrow tube fading out shortly before mantle collar.
Hindgut typical.
Fir. 173. a-b, Ulu-ra cookeana, new spec.es. Station 865, Mt. Aorai. 5,600-6,300 ft. elevation, Tahiti, Society Islands. Holotyp* BPBM
145289; c-e, Libera m,'™™, new species. Station 865, Mt. Aorai, 5,flOO-6.300 ft. elevation, Tahiti Society Islands. Holotype
Scale lines equal 1 mm. Figure rf shows microradial ribbing on part of last two whorls. Figures a-b by YK reproduced through
Bernice P. Bishop Museum; c-e (MM).
401
402
SOLEM: ENDODONTOID LAND SNAILS
Ovotestis could not be located in apical liver mass. Hermaphro-
ditic duct as in L. bursatella. Albumen gland, talon, and carrefour
not differentiated from simple S-loop connecting head of prostate-
uterus to hermaphroditic duct. Prostate proportionately of very
small acini, opening into narrow tube. Uterus bipartite, proportion-
ately larger than prostate, normal in size.
Vas deferens entering penis about 0.25 mm. below apex, lightly
attached to penioviducal angle. Penial retractor arising from
diaphragm, inserting directly on head of penis. Penis (fig. 172a, P)
about 5.9 mm. long, tapering apically, sharply constricted at base,
evenly expanded medially. Internally with a single high pilaster
extending from atrium to apex, lower and broadly rounded on basal
quarter, with a second much lower and more broadly rounded
pilaster on lower half of penis. Atrium short, relatively broad.
Free oviduct equal in length to prostate, same diameter as vas
deferens. Spermatheca with very small oval head, shaft much
slenderer than free oviduct, inserting directly onto penioviducal
angle.
Free muscle system as in Libera bursatella.
Buccal mass slender and elongated, with small generative sac.
(Based on BPBM 145289, two fragmentary examples.)
Libera gregaria Garrett, 1884. Figure 175a-c.
Libera gregaria Garrett, 1884, Jour. Acad. Nat. Sci., Philadelphia,
9, (1), p. 36, pi. 2, figs. 6, a, b — southwest part of Moorea,
Society Islands; Ponsonby, 1910, Proc. Malacol. Soc. London, 9,
(1), p. 42.
Helix (Libera} gregaria (Garrett), Tryon, 1887, Man. Conchol,
(2), 3, p. 72, pi. 13, figs. 83-84.
Endodonta (Libera) gregaria (Garrett), Pilsbry, 1893, op. cit., (2),
9, p. 24.
Diagnosis. — Shell quite large, diameter 6.27-7.26 mm. (mean
6.72 mm.), with 634-7'/2 normally coiled whorls. Apex and early spire
flat or barely elevated, whorls of spire descending slightly more
rapidly, body whorl usually deflected slightly below periphery of
penultimate whorl, rarely deflected markedly, H/D ratio 0.437-0.577
(mean 0.498). Umbilicus secondarily narrowed to form brood
chamber by gradual inward growth of baso-columellar margin during
last whorl and one-half, near aperture closure speeded by partial
detachment of parietal wall, opening highly irregular in shape and
size. Postnuclear sculpture of narrow, broadly V-shaped, protractive-
ly sinuated, rather crowded radial ribs, 155-198 (mean 177.8) on the
body whorl, whose interstices are 2-4 times their width. Micro-
sculpture of fine radial riblets, four to six between each pair of major
ribs, crossed by exceedingly fine and crowded spiral riblets,
occasionally with traces of narrow, rather widely spaced secondary
spiral cording. Sutures shallow, whorls flatly rounded down to
distinct supraperipheral sulcus, periphery weakly protruded into a
threadlike keel, lower palatal wall with a distinct subperipheral
sulcus, evenly and more strongly rounded down to very prominent
sulcus before baso-columellar margin. Columellar wall deeply
concave and U-shaped due to extreme umbilical narrowing. Aperture
subquadrangular, more strongly rounded below than above
protruded periphery, inclined about 25° from shell axis. Parietal
barriers 2, rarely (2 per cent) a 3rd present, extending posteriorly to
line of vision: upper parietal slightly more elevated and expanded
above on posterior third, with very gradual anterior descension; 2nd
parietal equal in height posteriorly, anterior half threadlike,
extending slightly beyond end of upper parietal. Columellar wall
deeply concave, surmounted by prominent, crescentic, broad barrier,
that twists distinctly upward from plane of coiling during its descent
across top of Columellar callus. Palatal barriers 3, rarely 2,
moderately deeply recessed, extending posteriorly about one-eighth
whorl: lower basal in position, high and slender, flattened above on
posterior half, with rather gradual anterior descension; 2nd palatal
usually slightly reduced in height, more flattened above, with more
gradual anterior descension, situated midway between lower palatal
and periphery; 3rd palatal, when present, supraperipheral, greatly
reduced in height, a raised threadlike trace more deeply situated
within aperture.
The large size, threadlike anterior termination of
the 2nd parietal and generally only slight deflection of
the body whorl combine to separate Libera gregaria
from the otherwise extremely similar L. recedens, in
which the periphery is normally markedly deflected,
there is no threadlike anterior half to the 2nd parietal,
and the mean diameter is more than a millimeter less
(5.69 mm.). Juvenile examples can be separated on the
basis of five whorl diameter, which is 2.1 mm. or less in
L. recedens and generally 2.3 mm. or more in L.
gregaria.
Description. — Shell large, with slightly more than 7'/2 relatively
loosely coiled whorls. Apex and early spire flat, later whorls
descending moderately, body whorl slightly deflected, depressed-
helicoidal in form, H/D ratio 0.524. Apical whorls and upper, spire
with sculpture eroded. Lower spire and body whorl with fine,
protractivelv sinuated radial ribs, about 170 on the body whorl,
whose interstices are about twice their width. Microsculpture eroded.
Sutures shallow, whorls flatly rounded above acutely angulated
periphery, evenly rounded on basal margin. Color mainly leached
from shell with traces of reddish maculations remaining. Umbilicus
strongly constricted to form brood chamber by growth of last whorl
and a half. Partial parietal wall detachment produced a thin plate
that covered much of the umbilicus and sealed several embryos
inside the brood chamber. Aperture subcrescentic, flattened laterally
above protruded periphery, inclined about 20° from shell axis.
Parietal barriers 2, extending slightly more than one-quarter whorl:
upper high and lamellate, elevated on posterior third, with very
gradual anterior descension; lower parietal equally high posteriorly
but with anterior half low and threadlike. Columellar wall with
heavy callus surmounted by a high, broadly rounded barrier, with
gradual anterior descension, extending up onto shell lobe that
constricts umbilicus. Palatal barriers 3, moderately recessed, about
one-eighth whorl long: lower 2 subperipheral, high, crescentic,
bladelike, with gradual anterior descension; 3rd palatal V-shaped,
shorter, supraperipheral, threadlike. Height of lectotype 3.59 mm.,
diameter 6.86 mm.
Lectotype. — Society Islands: southwest part of
Moorea. Collected by Andrew Garrett. ANSP 47825.
Range. — Two valleys on southwest part of
Moorea, Society Islands (Garrett, 1884, p. 36).
Paratypes. - BPBM 4881, ANSP 290106.
Material. — Moorea (74 specimens, BPBM 4881,
BPBM 167412, FMNH 156776, RSM 1961.61.56).
Unlocalized and Society Islands (27 specimens, BPBM
8597-8, BPBM 87517, FMNH 46359, ANSP 47825,
ANSP 290106).
Remarks. — Typical adults of Libera recedens and
L. gregaria are readily separable by the smaller size
(table C) and much greater whorl deflection of the
former. Juveniles and specimens of L. gregaria with
abnormally large body whorl deflection can be sepa-
rated by the distinct differences in early whorl
diameter (table CI). Although Garrett's figures suggest
that L. recedens is much more sharply keeled, this is
not a reliable character for separation. The differences
cited above should be relied on for identification.
Available material was not dimorphic in any
character measured, so that there is no evidence of
SYSTEMATIC REVIEW
403
f
a-b,e-f
FIG. 174. a-c, Libera bursatella bursatella (Gould). Station 863, Mt. Aorai, 4,700-5,500 ft. elevation, Tahiti, Society Islands. Neotype of
Helix bursatella Gould, 1846. BPBM 142059; d-f, Libera bursatella orofenensis, new subspecies. Station 946, Mt. Orofena, 5,500-5,700 ft.
elevation, Tahiti, Society Islands. Paratype. BPBM 145587. Scale line equals 1 mm. Figures c and d have microsculpture omitted from major ribs
and do not show microspiral ribbing. Drawings by YK reproduced through the courtesy of Bernice P. Bishop Museum.
differences between populations in the two valleys.
Unfortunately, Garrett did not name the valleys or
indicate associated species. They were found "congre-
gating in immense numbers on the underside of loose
stones." (Garrett, 1884, p. 36). The large size of
specimens from Garrett's collection (table CIII, BPBM
4881) probably reflects collection bias, Garrett having
retained large specimens for his own collection.
Comments on the unusual form of umbilical
closure are given below under L. recedens.
Libera recedens Garrett, 1884.
d-f.
Figures 170; 175
Libera recedens Garrett, 1884, Jour. Acad. Nat. Sci., Philadelphia,
9, (1), p. 36, pi. 2, fig. 7 — one valley on west side of Moorea,
Society Islands; Ponsonby, 1910, Proc. Malacol. Soc. London, 9,
(1), p. 42.
Helix (Libera) recedens (Garrett), Tryon, 1887, Man. Conchol.,
(2), 3, p. 72, pi. 13, fig. 85.
Endodonta (Libera) recedens (Garrett), Pilsbry, 1893, op. cit., (2),
9, pp. 23-24, pi. 9, fig. 34 (radula).
Diagnosis. — Shell of average size, diameter 5.36-6.67 mm. (mean
5.66 mm.), with 6%-7l/2 normally coiled whorls. Apex usually slightly
404
SOLEM: ENDODONTOID LAND SNAILS
FIG. 175. a-c, Libera gregaria Garrett. Moorea, Society Islands. Paratype. BPBM 4881; d-f, Libera recedens Garrett. Moorea, Society
Islands. Paratype. BPBM 2682. Scale lines equal 1 mm. Microsculpture on major ribs and microspirals omitted in c and d. Drawings by YK
reproduced through the courtesy of Bernice P. Bishop Museum.
elevated, lower whorls of spire descending progressively more rapidly,
body whorl deflected drastically below periphery of penultimate
whorl, H/D ratio 0.464-0.627 (mean 0.553). Umbilicus gradually
narrowed at first by inward growth of baso-columellar margin,
drastically narrowed on last whorl of growth by combination of
parietal wall detachment and continued inward growth of baso-
columellar margin, opening in adult very narrow and irregular so
that measurements could not be made in a meaningful fashion.
Postnuclear whorls with narrow, low, broadly V-shaped, protractive-
ly sinuated radial ribs, 152-198 (mean 178.2) on the body whorl,
whose interstices are 3-5 times their width. Microsculpture a lattice
of very fine radial riblets, five to eight between each pair of major
ribs, crossed by distinctly finer and more crowded spiral riblets. A
secondary sculpture of fine, rather widely and irregularly spaced
spiral cords is visible on various portions of better preserved
specimens. Sutures shallow, whorls flatly rounded down to promi-
nent supraperipheral sulcus, periphery a broadly rounded and
protruded keel, subperipheral sulcus stronger than supraperipheral.
lower palatal and basal margins evenly and rather strongly rounded
down to very prominent sulcus just before knife-edge baso-
columellar margin. The extreme body whorl deflection and resultant
parietal wall detachment has combined with the strong inward
growth of the baso-columellar margin to produce a characteristic
deep concavity on the columellar wall at the aperture which is not
duplicated by other Libera (fig. 170). Aperture subquadrangular.
more strongly rounded below than above, periphery markedly
protruded, inclined about 20° from shell axis. Parietal barriers 2,
extending posteriorly to line of vision: upper high and bladelike,
slightly more elevated on posterior visible third, with very gradual
anterior descension until just before termination; 2nd parietal about
one-half length of upper parietal, recessed to midpoint of upper,
equally high and expanded above posteriorly, with rather sharp
SYSTEMATIC REVIEW
405
descension, very rarely (2 of 95) with an anterior threadlike extension
to point opposite end of upper parietal. Columellar wall distorted by
pattern of growth, surmounted by a very broad and prominent,
crescentic barrier that twists slightly upward from plane of coiling
during its descent across middle of columellar callus. Palatal barriers
3, rarely with supraperipheral greatly reduced or absent, extending
posteriorly about three-sixteenths of a whorl, deeply recessed within
aperture: lower basal in position, high and slender, flattened above
on posterior half with rather sharp anterior descension; 2nd midway
between 1st palatal and periphery, slightly reduced in height, a little
longer, with more gradual anterior descension; 3rd supraperipheral,
located nearer periphery than parietal-palatal margin, greatly
reduced in height, a ridgelike barrier with very gradual anterior
descension, usually slightly shorter than 2nd palatal.
Adult specimens of Libera recedens can be
separated from its close relatives, L. gregaria, by its
smaller size, abrupt deflection of the body whorl below
the periphery of the penultimate, absence of a
threadlike anterior half to the 2nd parietal, and
generally greater H/D ratio. Of the Tahitian species,
only L. bursatella has similar appearing and spaced
sculpture. It differs most obviously in its complete
absence of a columellar barrier.
Description. — Shell of average size, with slightly more than 7'/8
normally coiled whorls. Apex and spire slightly elevated, weakly
rounded above, last two-thirds of body whorl descending rapidly and
strongly deflected below periphery, parietal wall partly detached,
H/D ratio 0.494. Apical whorls lu>, sculpture mostly eroded.
Postnuclear whorls with low, broadly rounded, protractively sinuated
radial ribs, about 165 on the body whorl, whose interstices are 2-4
times their width. Microsculpture of fine radial riblets, five to eight
between each pair of major ribs, crossed by much finer and more
crowded spiral riblets and a few irregularly spaced spiral cords that
are most prominent on shell base. Sutures shallow, whorls flatly
rounded above protruding periphery with prominent supraperipheral
and subperipheral sulci. Color light yellow horn with narrow,
crowded, zigzag, reddish f lammulations. Umbilicus partially
constricted by accelerating inward growth of baso-columellar margin
over last whorl and a half, parietal wall detached and nearly closing
umbilical opening. Aperture subcrescentic, with protruding pe-
riphery, inclined about 30° from shell axis. Parietal barriers 2,
extending posteriorly to line of vision: upper low and bladelike,
becoming higher on posterior third; lower posteriorly equal in height
but recessed to midpoint of upper, with sharper anterior descension.
Columellar barrier high, broadly twisted up onto shell lobe, with
gradual anterior descension. Palatal barriers 3, recessed, extending
about three-sixteenths of a whorl: 2 lower subperipheral, thin,
bladelike ridges with gradual anterior descension, flattened and
expanded above on posterior two-thirds, with gradual anterior
descension; upper a low, threadlike ridge situated one-third of way
between periphery and upper palatal margin, shorter and more
deeply recessed. Height of lectotype 2.94 mm., diameter 5.94 mm.
Lectotype. — Society Islands: west side of Moorea.
Collected by Andrew Garrett. ANSP 47827.
Range. — Lower part of one valley on west side of
Moorea, Society Islands (Garrett, 1884, p. 36).
Paratypes. - ANSP 290107, BPBM 2682.
Material. — Moorea (55 specimens, BPBM 2682,
BPBM 167413, FMNH 46425, FMNH 156777, AMS,
Edinburgh). Society Islands (5 specimens, ANSP
47827, ANSP 290107, FMNH 117054). No locality (1
specimen, Edinburgh).
Remarks. — The lectotype has the umbilical-
parietal shield broken. It is almost certainly the
specimen figured in Garrett (1884, pi. 2, fig. 7), and is
more sharply angulated than most specimens.
L. recedens and L. gregaria are obviously closely
related, differences in the body whorl deflection
causing the size and shape changes (table C). Specific
separation, rather than subspecific, is indicated be-
cause of the marked early whorl size difference (table
CI) and lack of intermediate specimens. Rib counts of
the two species are identical, 178.2 for recedens and
177.8 for gregaria, the significant difference in rib
spacing, 9.57 in recedens and 8.16 in gregaria, being an
artifact of reduced diameter in the former caused by
greater whorl deflection.
Comparing mean dimensions of the two species
(tables C, CI), L. recedens is 6.3 per cent smaller at
three whorls; 8.4 per cent at four whorls; 12.1 per cent
at five whorls; 15.8 per cent at adult size; but only 6.8
per cent less in adult height — reflecting the greater
body whorl deflection. The increase of 9.9 per cent in
mean H/D ratio for L. recedens is caused by the
greater body whorl deflection and more than
compensates for the slightly lower H/D ratio to be
expected in a smaller shell.
Pilsbry (1893-1895, p. 23, pi. 9, fig. 34) illustrated
eight radular teeth of L. recedens and reported a
formula of 15-1-15. He did not differentiate between
lateral and marginal teeth in the count, but did in his
discussion. The figures show no differences from those
of other Libera examined during this study that can
not be interpreted as caused by differences in optical
equipment.
Both L. gregaria and L. recedens have unusual
umbilical closures that result in irregular narrowing of
the openings, making meaningful measurements of the
openings impossible. In both species the normal
pattern of a slightly slanted columellar wall (fig. 184c,
f) extending anteriorly of the lower palatal lip margin
has been altered (fig. 175b, f). The columellar lip and a
detached portion of the parietal wall are reflected
inward almost perpendicular to the shell axis and
progressively cover the umbilical opening (fig. 170)
with a very thin plate. Many museum specimens have
the plate partly broken, but whether this was an
accident during years in the collections or resulted
from the activities of emerging young is unknown.
Specimens with intact closures, such FMNH 46359,
have young retained inside the umbilicus. This altered
form of umbilical closure, which occurs during the last
whorl to whorl-and-a-quarter of growth, is an obvious
adaptation to the low spire height in these two species.
While other Libera, which have proportionately much
higher spires, can take two whorls to gradually narrow
the umbilicus and still preserve an adequate brood
chamber, in L. gregaria and L. recedens the low spire
results in a shallow chamber that would be very small
if two whorls of narrowing were utilized. Hence the
comparatively sudden and directly inward growth of
the columellar wall and parietal callus maintains an
adequate volume size to the brood chamber.
406
SOLEM: ENDODONTOID LAND SNAILS
,>ff' VlUifiMMt^/iHWT'
"•* • "v' Jfc^iimMin'W" ' f ~*«9
FlG. 176. Libera dubiosa Ancey: a-c, typical example. Moorea, Society Islands. BPBM 2235; d-f, gerontic individual. Moorea, Society
Islands. BPBM 4916. Scale lines equal 1 mm. Microsculpture in d worn off, only major ribs and secondary spiral cording visible. Drawings by
YK reproduced through the courtesy of Bernice P. Bishop Museum.
Libera dubiosa Ancey, 1889. Figure 176a-f.
Libera coarctata Garrett, 1884 (not Pfeiffer, 1850), Jour. Acad.
Nat. Sci., Philadelphia, 9, (1), pp. 34-35, pi. 2, fig. 10 - valleys
on north and east sides of Moorea, Society Islands.
Libera heynemanni var. dubiosa Ancey, 1889, Le Naturaliste, (2),
11, (59), pp. 190-191 - locality unknown.
Diagnosis. — Shell slightly smaller then average, diameter 4.84-
5.88 mm. (mean 5.35 mm.), with 6'/2-8 rather tightly coiled whorls.
Apex and spire markedly elevated, rounded above, occasionally apex
distinctly flattened, body whorl usually descending slightly below
periphery of penultimate whorl, occasionally descending moderately,
H/D ratio 0.525-0.697 (mean 0.587). Umbilicus secondarily narrowed
to form brood chamber by gradual inward growth of baso-columellar
margin over a little more than the last two whorls, resulting opening
circular or subcircular, contained 3.85-7.00 times (mean 5.38) in the
diameter. Postnuclear sculpture of low, narrow, somewhat crowded,
protractively sinuated radial ribs, 111-138 (mean 125.2) on the body
whorl, whose interstices are 3-6 times their width. Microsculpture of
fine radial riblets, five to eight between each pair of major ribs,
crossed by exceedingly fine and crowded spiral riblets that are barely
visible under 96 X magnification. Secondary microsculpture of
narrow, rather sharply defined and relatively widely spaced spiral
cords, that become broader and much more crowded on shell base.
Major radial sculpture usually reduced on shell base. Sutures
shallow, whorls flatly rounded down to moderately protruded
threadlike periphery, supraperipheral sulcus generally weak to
absent, subperipheral sulcus relatively prominent, lower palatal wall
SYSTEMATIC REVIEW
407
strongly rounded down to basal margin which is flattened to distinct
sulcus before baso-columellar margin. Aperture subovate, strongly
flattened laterally above weakly protruded periphery, inclined about
30° from shell axis. Parietal barriers 2, extending posteriorly to line
of vision: upper parietal very high and slender on posterior third,
gradually descending to anterior third which is a ridgelike lamellar
blade; 2nd parietal with posterior portion equal in height to elevated
posterior of upper parietal, descending to parietal wall at approxi-
mate midpoint of upper parietal, either with (33 per cent) or without
(67 per cent) a threadlike anterior extension to point slightly in front
of upper parietal termination. Columellar wall with prominent, high,
broad, crescentic barrier that twists slightly upward from plane of
coiling as it gradually descends across top of columellar callus.
Palatal barriers 4, deeply recessed, extending posteriorly slightly
more than one-eighth whorl: lower basal in position, flattened above
on posterior third, with gradual anterior descension, often visible
from apertural view only with difficulties; 2nd and 3rd slightly
higher, longer, more flattened above, with progressively more gradual
anterior descension, both subperipheral; 4th supraperipheral, located
nearer periphery than parietal-palatal margin, greatly reduced in
height, an elevated ridgelike barrier with very gradual anterior
descension.
Both Libera garrettiana and L. spuria are closely
related to L. dubiosa. L. garrettiana, from the
northwest part of Tahiti, differs in its complete lack of
major radial sculpture, smaller size, and lower whorl
count. L. spuria is intermediate in sculpture, usually
retaining major radial ribbing on the first three or four
postnuclear whorls, but the major sculpture is absent
from the lower spire and body whorl. The secondary
spiral cording is very fine and crowded compared with
L. dubiosa.
Types. — Ancey's material was not located. As in
the case of L. spuria, I have chosen not to select a
lectotype.
Range. — Valleys on north and west sides of
Moorea, Society Islands (Garrett, 1884, p. 35).
Material. — Moorea (57 specimens, BPBM 2235,
BPBM 4916, FMNH 156778, AMS, Zurich, RSM
1961.61.42). No locality (5 specimens, BPBM 8675,
BPBM 10001, BPBM 170911, BPBM 170915, FMNH
46389).
Remarks. — Union of the shells that Garrett
misidentified as "coarctata" with Ancey's Libera
dubiosa from an unknown locality is based upon the
distinctive sculpture, 4 palatal barriers and 5 mm.
diameter mentioned by Ancey in his description. This
combination of characters is found only in the
material reported on by Garrett. It is not even partly
duplicated by another species of Libera.
Normal specimens (fig. 176a-c) can readily be
recognized as being closely related to garrettiana, but
gerontic shells with reduced barriers and worn
sculpture (fig. 176d-f) are more difficult to identify.
Possibly L. dubiosa and L. spuria are only subspe-
cifically separable, but the difference in whorl count
and mean size is large enough that I am ranking them
as species. Material from the various sources located
(table CIII) probably all originated from Garrett.
Except for the smaller size of the AMS set, there is no
significant variation in size or shape.
The similarities of L. dubiosa, L. spuria, and L.
garrettiana are obviously many, but their degree of
relationship is uncertain. They show a progressive
reduction in radial sculpture and intensification of
spiral sculpture that is correlated with size reduction.
The heavily sculptured L. dubiosa is much larger than
those with reduced radial sculpture. Probably there is
no direct phylogentic relationship between the three,
but they were derived from a common stock. Certainly
they retain the most generalized barrier structure in
the genus.
Libera spuria Ancey, 1889. Figure 177a-b.
Libera heynemanni var. Spuria Ancey, 1889, Le Naturaliste, (2),
11, (59), p. 190 -Tahiti.
Diagnosis. — Shell small, diameter 4.18-5.49 mm. (mean 4.83
mm.), with 5%-6'/2 rather tightly coiled whorls. Apex and spire
strongly elevated, usually rounded to slightly flattened above, body
whorl normally not descending more rapidly, occasionally slightly
deflected, H/D ratio 0.500-0.697 (mean 0.595). Umbilicus slightly
narrowed secondarily to form a brood chamber by very gradual
inward growth of baso-columellar margin, resulting opening normally
circular, contained 4.00-7.80 times (mean 5.34) in the diameter.
Postnuclear whorls with narrow, low, inconspicuous and relatively
crowded radial ribs on upper spire that are absent from lower spire
and body whorl. Microsculpture normally of very fine radial riblets,
crossed by slightly finer and more crowded spiral riblets, with a
secondary sculpture of low and quite crowded spiral cords that may,
particularly on shell base, become more prominent than radial
riblets. Sutures shallow, whorls flatly rounded down to weak or
moderately prominent supraperipheral sulcus, periphery weakly
protruded into a threadlike keel, normally without, sometimes with a
subperipheral sulcus. Lower palatal wall evenly and more strongly
rounded down to prominent sulcus and sharply protruded baso-
columellar margin, columellar wall flattened internally. Aperture
subquadrangular, more strongly rounded below than above slightly
protruded periphery, inclined about 20° from shell axis. Parietal
barriers 2, extending posteriorly to line of vision: upper high and
slender, weakly expanded above on posterior half, with gradual
anterior descension; 2nd normally recessed to midpoint of 1st,
equally high or slightly higher on posterior section, with rather sharp
anterior descension, in juvenile and some adult individuals with a
threadlike anterior extension to point opposite end of upper parietal.
Columellar wall with single, high, crescentic, deeply recessed, slightly
supramedial barrier, with gradual anterior descension almost to top
of columellar callus, barely visible from normal apertural view.
Palatal barriers variable in number, normally (87.1 per cent) 4,
occasionally (9.7 per cent) with 1st absent, rarely (3.2 per cent) with
both 1st and 4th absent, deeply recessed, extending posteriorly more
than one-eighth whorl: lower normally basal in position, slightly to
greatly reduced in height from 2nd and 3rd, sometimes absent, with
rather gradual anterior descension; 2nd and 3rd subperipheral, quite
high and prominent, weakly expanded and flattened above on
posterior half, with progressively more gradual anterior descension,
although descending more sharply than 1st; 4th, when present, a low
and deeply recessed, threadlike to weakly lamellar supraperipheral
trace.
Differences between Libera spuria and L. garret-
tiana are few, consisting primarily in spuria having
major radial ribs present on the upper spire and
generally rather indistinct secondary spiral cording. L.
garrettiana has no trace of major radial ribbing on the
shell and the secondary spiral cording normally is
quite prominent. L. dubiosa from Moorea is slightly
larger and has the major radial ribs extending on to
408
SOLEM: ENDODONTOID LAND SNAILS
Fl<;. 177. a-b, Libera spuria Ancey. No locality. BPBM 9708; c-e, Libera garrettiana, new species. Tahiti, Society Islands. Holotype.
BPBM ±2:i4. Scale lines equal 1 mm. Microsculpture only suggested in c. Drawings by YK reproduced through the courtesy of Bernice P. Bishop
Museum.
both the lower spire and body whorl. The much larger
L. heynemanni lacks all trace of major radial ribbing.
Types. -- No material in the Bernice P. Bishop
Museum, National Museum of Wales (Cardiff), and
Institut Royal des Sciences Naturelles de Belgique
(Brussels), the logical repositories for Ancey types, was
labelled as this species. His types are so widely
dispersed, however, that, in the absence of localized
material, I have chosen not to select a neotype.
Range. — Probably Tahiti, but possibly Moorea,
Society Islands.
Material. - Tahiti (30 specimens, FMNH 46417,
FMNH 90622, FMNH 117051, Zurich, RSM). No
locality (70 specimens, BPBM 9708, BPBM 189939,
FMNH 7662, FMNH 73893, FMNH 156775, RSM
1961.61.44).
Remarks. — Ancey (loc. cit.) inferred that Libera
spuria and L. dubiosa were from the same collection,
but the latter is a Moorean species, while Ancey cited
Tahiti as the habitat for L. spuria. Only new
collections will settle the problem of locality. They are
very similar in appearance, but the size and probable
locality difference combined to suggest specific separa-
tion.
None of the Bishop Museum material had exact
locality and apparently this was not a species collected
TABLE CIII. - LOCAL VARIATION IN SOCIETY ISLAND LIBERA
Number of
specimens
Height
Diameter
H/D Ratio
Whorls
D/U Ratio
recedens
3.07±0.063
(2.61-3.27)
5.55±0.030
(5.42-5.69)
0.553±0.0123
(0.476-0.602)
7+
(6 5/8-7 1/4)
BPBM 2682, 10
BPBM 167413
ANSP 47827. 4
ANSP 290107
3.02i0.062
(2.94-3.20)
5.62i0.125
(5.42-5.95)
0.539±0.0210
(0.494-0.590)
7 1/8
(7-7 1/4)
RSM 1961.61.48 33
3.14±0.036
(2.81±3.59)
5.65i0.056
(5.10-6.73)
0.557±0.0057
(0.500-0.627)
7+
(6 1/8-7 1/2)
gregaria
RSM 1961.61.56 46
3.30±0.042
(2.75-3.99)
6.67i0.032
(6.27-7.12)
0.494±0.0052
(0.437-0.577)
7 1/8-
(6 5/8-7 3/4)
BPBM 4881 5
3.58±0.073
(3.46-3.86)
7.01±0.104
(6.73-7.25)
0.512±0.0121
(0.482-0.546)
7 3/8-
(7 1/8-7 1/2)
BPBM 167412 13
3.43±0.058
(3.14-3.73)
6.79±0.055
(6.41-7.06)
0.505i0.0067
(0.466-0.540)
7 1/4
(6 3/4-7 1/2)
retunsa
BPBM 2233, 9
BPBM 167410,
BPBM 170906,
BPBM 170913
2.84±0.071
(2.48-3.14)
4.35i0.077
(3.92-4.64)
0.654±0.0190
(0.567-0.758)
6 3/8+
(6-7)
4.17±0.203
(3.38-5.00)
streptaxon
Paris A 5
3.32±0.114
(2.88-3.46)
6.24±0.129
(5.95-6.67)
0.554±0.0103
(0.520-0.582)
8-
(7 3/4-8)
7.13±0.264
(6.54-8.06)
Paris B 6
3.28±0.070
(3.07-3.53)
6.20*0.064
(5.95-6.41)
0.529±0.0118
(0.500-0.575)
7 3/4-
(7 1/2-8)
6.44±0.249
(5.53-7.38)
heynemanni
BPBM 170907-8 6
3.44±0.142
(2.94-3.86)
6.30±0.238
(5.23-6.67)
0.547±0.0094
(0.522-0.578)
6 3/4-
(6 1/4-7)
4. 64+.0.261
(4.00-5.72)
incognata
BPBM 167407,
BPBM 175610
BPBM 43. 4. 5. 187-8 5
4. 66±0.434
(3.92-5.42)
5.05±0.086
(4.71-5.16)
7.04±0.087
(6.86-7.12)
7.48±0.076
(7.32-7.71)
0.66U0.0548
(0.571-0.761)
0.675±0.0130
(0.631-0.705)
8 1/8+
(7 5/8-8 7/8)
8+
(7 1/2-8 1/2)
5.99±1.057
(3.89-7.27)
5. 55±0.483
(3.80-6. 58)
dubiosa
BPBM 2235 4
3.09±0.129
(2.88-3.46)
5.25±0.056
(5.10-5.36)
0.589±0.0245
(0.561-0.662)
7 1/8+
(7-7 5/8)
No Measurement
BPBM 4916 6
3.15*0.171
(2.75-3.79)
5.39±0.075
(5.23-5.62)
0.583±0.0245
(0.525-0.682)
7 1/8-
(65/8-7 7/8)
No Measurement
AMS (subadult) 5
2. 70±0.045
(2.58-2.81)
5.00±0.072
(4.87-5.23)
0.538±0.0067
(0.525-0.563)
6 3/4
(6 1/2-7)
4.48±0.313
(3.85-5.65)
Zurich 15
3.21±0.070
(2.78-3.74)
5.45±0.040
(5.10-5.70)
0.588±0.0096
(0.540-0.657)
7 1/4-
(7-7 1/2)
5.68i0.225
(4.58-7.00)
RSM 1961.61.42 14
3.41±0.045
(3.20-3.66)
5.59±0.048
(5.36-5.88)
0.611±0.0075
(0.570-0.655)
7 1/4+
(6 7/8-7 5/8)
5. 79±0.176
(4.55-7.00)
spuria
BPBM 9708, 7
BPBM 189939
2.68±0.092
(2.22-2.94)
4.56±0.092
(4.18-4.84)
0.590±0.0230
(0.500-0.672)
6 1/8
(5 3/4-6 3/8)
4. 94±0.329
(4.00-6.09)
Zurich 6
2.77*0.062
(2.48-2.91)
4. 64±0.063
(4.54-4.93)
0.597±0.0114
(0.547-0.627)
6 1/4
(6-6 1/2)
5.72*0.147
(5.27-6.20)
RSM 1961.61.44 60
2. 92±0.035
(2.42-3.46)
4. 89i0.031
(4.44-5.49)
0.596±0.0056
(0.513-0.697)
6 5/8+
(6 1/8-71/2)
S-. 35±0.107
(4.00-7.80)
garrettlana
BPBM 2234 7
2.82±0.066
(2.55-3.07)
5.04±0.084
(4.71-5.29)
0.55910.0087
(0.534-0.603)
6 5/8-
(6 3/8-7)
5.27±0.147
(4.71-5.79)
AMS C50, 7
AMS C28644
2. 66±0.087
(2.35-2.91)
4.79±0.065
(4.57-5.07)
0.555±0.0140
(0.503-0.607)
6 3/8
(6-6 3/4)
4.75±0.246
(3.81-5.68)
409
410
SOLEM: ENDODONTOID LAND SNAILS
by Garrett. Thus the small size of the BPBM sets
(table CIII) indicates nothing of significance except
trading bias by collectors. The origin of the large set
from the Fulton collection (RSM 1961.61.44) could not
be established.
Libera garrettiana, new species. Figure 177c-e.
Libera heynemanni Garrett, 1884 (not Pfeiffer, 1862), Jour. Acad.
Nat. Sci., Philadelphia, 9, (1), p. 35, pi. 2, fig. 9 - several valleys
on northwest part of Tahiti, Society Islands.
Helix (Libera) heynemanni Tryon, 1887 (not Pfeiffer, 1862), Man.
Conchol., (2), 3, pi. 13, fig. 82. Copied from Garrett (1884, pi. 2,
fig. 9).
Diagnosis. — Shell small, diameter 4.51-5.29 mm. (mean 4.85
mm.), with 55/e-7 normally coiled whorls. Apex and spire rather
strongly elevated, distinctly rounded above, last whorl only rarely-
descending more rapidly, H/D ratio 0.503-0.607 (mean 0.559).
Umbilicus secondarily narrowed to form brood chamber by gradual
inward growth of baso-columellar margin over last two whorls,
resulting opening circular, contained 3.81-5.57 times (mean 4.91) in
the diameter. Postnuclear whorls without major radial ribbing,
having a velvety appearance under low (20x) magnification.
Microsculpture consisting of very fine and crowded radial riblets
with much finer and extremely crowded spiral riblets that are visible
only under 96 X magnification, normally with a secondary sculpture
of rather prominent spiral cords that are exaggerated in Figure 177c.
Sutures reduced to an impressed line, whorls flat or very gently
rounded down to shallow supraperipheral sulcus, periphery right or
acutely angled, very weakly protruded, lower palatal and basal
margins gently and evenly rounded down to prominent sulcus before
knife-edge sharp baso-columellar margin, walls of columella flat
internally. Aperture subquadrangular, slightly more strongly rounded
below than above weakly protruded periphery, inclined about 25°
from shell axis. Parietal barriers 2, extending posteriorly to line of
vision: upper high and bladelike, expanded and distinctly elevated
on posterior three-eighths, with very gradual anterior descension;
2nd recessed to point slightly in front of midpoint of upper parietal,
equally elevated and expanded above posteriorly, with rather sharp
anterior descension. Columellar wall with high, prominent, broadly
rounded crescentic barrier, with gradual anterior descension almost
to top of columellar callus, deeply recessed within aperture. Palatal
barriers normally 4, rarely (4.6 per cent) with upper absent, deeply
recessed, extending posteriorly slightly less than one-eighth whorl:
lower basal in position, much lower than 2nd and 3rd, flattened
above on posterior third, with gradual anterior descension; 2nd and
3rd elevated and bladelike, flattened above on posterior half to five-
eighths, weakly expanded above, with progressively more gradual
anterior descension, deeply recessed within aperture; 4th supraperi-
pheral, greatly reduced in height, a threadlike to low, ridgelike
lamellar trace, with very gradual anterior descension.
Libera garrettiana is distinguished by its complete
absence of major radial ribbing and the general
predominance of secondary spiral cording. L. spuria is
extremely similar, but generally is slightly more
elevated and has major radial ribbing retained on the
upper spire. In general, specimens of L. spuria have
the whorls more strongly rounded and there is a
greater tendency toward size reduction and loss of the
1st palatal. The other species without major radial
sculpture, L. heynemanni, differs in its much larger
size (mean diameter 6.52 mm.) and the apparent total
absence of any sculpture.
Description. — Shell of average size, with 6% relatively loosely
coiled whorls. Apex and spire markedly elevated, rounded above, last
whorl not descending more rapidly. H/D ratio 0.538. Sutures very
shallow, whorls of apex and spire flattened above. Body whorl with
slightly protruding, acutely angulated keel, lower palatal wall more
strongly rounded. Embryonic whorls 1%, sculpture of extremely fine
radial ribs, whose interstices are about l'/2 times their width, with
very fine crowded spirals. Post apical whorls with radial sculpture of
exceedingly fine, closely spaced radial riblets, crossing much larger
and more prominent rounded spiral cords (fig. 177c). Color light
yellow horn, with prominent, reddish flammulations that become
zigzagged below periphery. Umbilicus constricted by expansion of
last two whorls and sharp inward protrusion of basal lip. Opening
nearly circular, contained 4.87 times in the diameter. Aperture
subquadrangular with rounded basal margin, inclined about 25° from
shell axis. Parietal wall with 2 barriers that extend posteriorly more
than one-quarter whorl: upper high and lamellate for entire length,
slightly expanded and minutely serrated above; lower deeply
recessed, extending about one-eighth whorl, equal in height to upper.
Columellar barrier a high, broadly rounded ridge, moderately deeply
recessed within aperture, descending gradually to top of columellar
callus. Columellar margin of lip extending sharply anteriorly. Palatal
barriers 4. deeply recessed: lower 3 high and bladelike. extending
about one-eighth whorl with gradual anterior descension, lowest one
smaller than upper 2; upper palatal a low, thin supraperipheral
lamellar ridge. Height of holotype 2.74 mm., diameter 5.10 mm.
Holotype. — Society Islands: northwest part of
Tahiti, Society Islands. Collected by Andrew Garrett.
BPBM 2234.
Range. — Valleys on northwest part of Tahiti,
Society Islands (Garrett, 1884, p. 35).
Paratypes. — Same as list of material.
Material. - Tahiti (62 specimens, BPBM 2234,
BPBM 87514, BPBM 170905, FMNH 156774, Zurich,
AMS C50, AMS C28644, RSM 1961.61.43). No locality
(51 specimens, BPBM 9709, BPBM 8603, BPBM
170904, BPBM 170909-10, BPBM 170912, BPBM
170914).
Remarks. — Garrett's confusion of this species
with L. heynemanni is readily understandable, partic-
ularly in view of the poor descriptions and illustrations
available to Garrett. The original measurements of
heynemanni cite a diameter of 5l/2 mm., which is above
the maximum recorded size for this species and within
the range of what I am calling heynemanni. That
species has no secondary spiral cording and normally
lacks the 4th palatal.
Probably the true size of L. garrettiana is between
that cited for the BPBM 2234 examples (biased to
large size) and those in the AMS (biased for small size)
(table CIII). Unfortunately, no exact locality is known
for this species.
Great pleasure is taken in naming this species
after Andrew Garrett, pioneer collector and student of
Pacific land mollusks.
Libera umbilicata, new species. Figure 178a-c.
Diagnosis. — Shell smallest in genus, diameter 3.66-3.79 mm.
(mean 3.71 mm.), with 6'/2-7'/2 normally coiled whorls. Apex and spire
strongly and almost evenly elevated, slightly rounded above, whorls
of lower spire descending progressively more rapidly, body whorl at
most only slightly deflected below periphery, H/D ratio 0.625-0.736
(mean 0.673). Umbilicus slightly narrowed to form brood chamber by
very gradual inward growth of baso-columellar margin, remaining
widely open, circular in outline, contained 2.94-3.41 times (mean
3.16) in the diameter. Postnuclear sculpture of prominent, very
SYSTEMATIC REVIEW
411
FlG. 178. a-c, Libera umbilicata, new species. Station 949, Mt. Orofena, 4,500 ft. elevation, Tahiti, Society Islands. Holotype. BPBM 145820;
d-f, Libera retunsa (Pease). Tahiti, Society Islands. Lectotype. BPBM 170913. Scale lines equal 1 mm. Microspiral sculpture not shown in c and
d, all microsculpture omitted from major ribs. Drawings by YK reproduced through the courtesy of Bernice P. Bishop Museum.
broadly V-shaped, widely spaced, strongly protractively sinuated
radial ribs, 26-32 (mean 29.3) on the body whorl, whose interstices
are 7-10 times their width. Microsculpture a lattice of very fine
radial riblets, approximately 30 between each pair of major ribs,
crossed by slightly finer and more crowded spiral riblets. Lower spire
and base of shell with indistinct, broadly rounded, irregularly spaced
secondary spiral cords. Sutures shallow, whorls rather flatly rounded
down to weak supraperipheral sulcus, periphery' a weak threadlike
keel with distinct subperipheral sulcus present, lower palatal and
basal margin gently and almost evenly rounded down to approxi-
mately right-angled baso-columellar margin, with columellar wall
flattened. Aperture subquadrangular, more strongly rounded above
than below the threadlike keeled periphery, inclined about 20° from
shell axis. Parietal barriers 2, extending posteriorly beyond line of
vision: upper high and slender, weakly expanded above on posterior
visible half with very gradual anterior descension; 2nd parietal
equally high and expanded above on visible posterior half,
descending rather rapidly to anterior third which is much lower, but
gradually and more evenly descending than upper parietal to point
behind or in front of upper's termination. Columellar wall with a
large, crescentic, quite broad, deeply recessed barrier, reaching to top
of thin columellar callus. Palatal barriers 3, moderately deeply
recessed, all subperipheral in position: lower very near baso-
columellar margin, much less elevated than parietal, flattened above,
with relatively sharp anterior descension; 2nd and 3rd progressively
reduced in height, more elongated, and with much more gradual
anterior descension.
Libera umbilicata is characterized by its ex-
tremely small size, very widely spaced radial ribs,
SOLEM: ENDODONTOID LAND SNAILS
threadlike keel, relatively wide umbilicus, and the
?xtremely long parietal barriers. The most similar
species. L. retunsa, differs in its total lack of palatal
barriers, absence of a keeL much stronger secondary
spiral sculpture, and possession of 43-54 major radial
ribs on the last whorl. All other Libera with reduced
major radial sculpture are at least 1 mm. larger in
Dean adult size.
Description. — Shell very small, with ~i rather tightly coiled
•rhorls. Apex and spire strongly elevated. sHshttv rounded above, last
arhori not descending more rapidly. H D ratio '.V736. Apical whork
1 4. sculpture completely eroded, viable in umbibcus as traces of
major radials with one to two microriblecs between. Postnuclear
aiwris with very widely spaced, broadly V-shaped, protractively
•inuated radial ribs. 30 on the body whorl whose interstices are •>-£•
times their width. Mkrosculpture of exceedingly fine radial riblets.
ibout -fc) between each pair of major ribs, crossed by slightly finer
ind more crowded spiral riblets. with vague secondary spiral cording
tisibie on body whorl above periphery' and base of shell ifig. :~~-
Ground color tight yellow bom. with extremely broad, reddish
Tammulations that almost coalesce above periphery, become
ripMgppd and fade out on shell base. Umbilicus broadly L -shaped.
>niy slightly secondarily narrowed to form brood chamber by inward
growth of baso-cohimellar margin, opening circular, contained i-5
imes in the diameter. Aperture subquadrangular. more strongly
•ounded above than below threadlike peripheral keel inclined about
TO' from shell axis. Parietal barriers 2. extending posteriorly beyond
ine of vision: upper very high and thin. posterior visible half slightly
ftevated and more expanded, with very gradual anterior descensk>n:
2nd parietal equally high on visible posterior half, rather abruptly
iescending to a raised threadlike anterior third that terminates
slightly behind end of upper parietal ColumeUar wall with a weak
rallus. surmounted by a very broad, high and crescenric barrier that
reaches barely to top of coIumeUar callus. Palatal barriers 3.
ubperipheral moderately deeply recessed, extending posteriorly
ihnost three-sixteenths of a whorl: lower very near baso-columellar
margin, slightly higher, shorter and with more abrupt anterior
iescension than 2nd and -3rd. which are progressively longer, lower
ind with more gradual anterior descension. Height of holotype 1.75
urn diameter 1~1 mm.
Holotype. — Society Islands: Tahiti. Station £49.
?ast side, south ridge of Mt. Orofena at 4.500 ft.
?levation. Collected by Harold St. John on September
JO. 19*4. BPBM 145820.
Range. — Mt. Orofena at 4.500 ft. elevation.
Tahiti. Society Islands.
Parafrpes. — Same as list of material.
Material. — Tahiti: east side, south ridge of Mt.
Orofena (Station 949). at 4.500 ft. elevation i4
specimens. BPBM 145820).
Remarks. — The only species of similar size.
Libera retunsa. also has widely spaced radial ribs, but
differs in the sharp descension of the body whorl,
rounded periphery, loss of apertural barriers, and the
much greater development of spiral cording ifig. 178d-
?». In retaining a columellar barrier and 3rd palatal L.
imbilicata is rather generalized, but the very widely
•paced sculpture, stronger keel and very high spire are
specialized conditions. Possibly the specimens were
slightly subadult and the umbilicus could become
narrower, but I suspect that only slightly greater
inward growth would be probable. The relatively high
whorl count l7-> suggests adult size and all specimens
showed at least a slight area of adult growth.
Libera retunsa (Pease. 1864). Figure 178d-f.
Hftix retunsa Pease. 1-*M. Proc. Zool Soc. London. 18*4. p. 670 -
no locality: Pfeiffer. 1868. Monog. hetic. viv.. 5. p. 220: Pfeiffer.
1876. op. «/.. 7. p. 256.
ftf»s retunsa ( Pease i. Pease. 1871. Proc. Zool Soc. London. 1871.
p. 475 — Tahiti Society Islands.
Libera retunsa I Pease I. Garrett. 1884. Jour. Acad. Sat. Sci..
Philadelphia. 9. tl>. p. 35. pi i fig. 8 - south side of Tahiti.
Society Islands: Ponsonby. 1910. Proc. Malacol Soc. London. 9.
I II. p. 41.
Heax < Liberal retuma H Pease). Tryon. 1887. Man. ConchoL. (2>. 3.
p. 71. pi 13. fig. >1.
Endodonta > Liberal retunsa i Pease*. Pit-try . 1*0- Man. ConchoL.
• 2 1. 9. p. 24.
Diagnosis. — Shell very small diameter 3.86-4.64 mm. I mean
4.30 mm. I. with -5~s-7 normally coiled whorls. Apex and early spire
slightly and evenly elevated, lower whorls descending much more
rapidly, body whorl deflected significantly below level of penultimate
whorl periphery. H D ratio 0.567-0.758 (mean 0.644). Umbilicus
secondarily narrowed to form brood chamber by gradual inward
growth of baso-columellar margin on last two whorls, opening
roughly ovate, slight indication of parietal callus detachment,
opening contained 3.28-5.00 times (mean 4.08> in the diameter.
Postnuclear sculpture of low. narrow, widely spaced, strongly
protractively sinuated radial ribs, 43->5 imean 51.2) on the body
whorl whose interstices are 4-7 times their width. Microseulpture of
prominent radial riblets. five to ten between each pair of major ribs,
crossed by exceedingly fine and crowded spiral riblets that are barely
visible under 96x magnification, with a secondary sculpture of
relatively narrow, quite prominent, widely spaced spiral cords that
are present over most of shell surface. Sutures impressed, whorts
strongly rounded down to very obtusely rounded or weakly
angulated periphery, lower palatal margin more strongly and evenly
rounded than in most Libera. baso-cohimellar margin protruded,
cohimellar wall flattened. Aperture ovate, strongly rounded above
and slightly less strongly rounded below obtusely rounded periphery,
inclined about 30~ from shell axis. Parietal wall with a single low
blade, extending posteriorly slightly more than one-quarter whorl
normally a tin ie supra medial in position, occasionally (1 of 11 > with
a short and deeply recessed lower 2nd parietal Columellar wall with
or without a single very deeply recessed, broadly rounded, submedial
lamellar swelling, viable only by extreme tilting of aperture when
present. Palatal wall normally without barriers, often (2 of 11 1 with
two very short and low. deeply recessed, threadlike, subperipheral
traces present.
The two species of similar size, Libera umbilicata
and L. micrasoma. both have two very large parietals
of equal length, prominent palatal barriers, and differ
considerably in sculpture character. L. micrasoma has
normal endodontid ribbing with more than one
hundred rather closely spaced ribs on the body whorl.
L. umbilicata has even more widely spaced major
radial ribbing, but differs in its greatly reduced
secondary spiral cording and in having about 30 very
fine microradials between each pair of major ribs. L.
streptajcon has very similar sculpture, but is imme-
diately separable by its much larger size, more
depressed shape, and presence of 2 prominent parietals
and 3 palatal barriers.
Description. — Shell small with 6H relatively tightly coiled
whorls. Apex and early spire somewhat flattened, later whorls
descending quite rapidly, body whorl strongly deflected. H D ratio
0 S5J Embryonic whorls l"-4. sculpture of equally spaced radial
SYSTEMATIC REVIEW
413
riblets. overshadowing smaller, much more closely spaced spiral
cords. Remaining whorls with low. protractively sinuated lamellar
radial ribs with hairlike periostracal projections, widely spaced.
whose interstices are 6-9 times their width. Almost equally prominent
is a sculpture of widely spaced spiral cords, particularly prominent
on shell base. Microsculpture (fig. 178d) of low. crowded lamellar
radial riblets. five to ten between each pair of major ribs, plus very
fine and crowded spiral riblets. Sutures relatively deep, whorls
strongly rounded above and down to faint trace of peripheral
angulation. evenly rounded down to sulcus before baso-columellar
margin. Umbilicus narrowed to form a brood chamber by inward
growth of parietal-palatal margin, slight detachment of parietal
callus, ovate, contained 4.78 times in the diameter. Color light horn,
with broad, widely spaced, reddish flammulations becoming sinuated
below periphery. Aperture ovate, flattened columellar margin,
inclined about 30° from shell axis. Parietal wall with 1 moderately
low barrier, extending slightly more than three-sixteenths of a whorl.
Columellar wall with thin callus and moderately prominent, broadly
rounded, deeply recessed barrier. Palatal wall without barriers.
Height of lectotype 2.94 mm., diameter 4.38 mm.
Lectotype. — Society Islands: Tahiti. Collected by
Andrew Garrett. BPBM 170913.
Range. — South side of Tahiti, Society Islands
(Garrett, 1884, p. 35).
Paratypes. - BPBM 2233. BPBM 170913.
Material. - Tahiti (10 specimens, BPBM 2233,
BPBM 167410, BPBM 170913, FMNH 46266). No
locality (1 specimen, BPBM 170906).
Remarks. — Two of the 11 specimens retained
very small and deeply recessed palatal barriers. The
remaining nine examples had no palatals. Although
reported as common on the south side of Tahiti
(Garrett, 1884, p. 35), no material has been collected in
this century and very few specimens were located in
museums. The complete absence of any peripheral
angulation or keeling, extreme deflection of the body
whorl and general absence of palatal barriers effective-
ly separate this species from the other Libera. While
the effect of the sculpture in L. retunsa is the same as
in L. streptaxon, the components are quite different.
Only the Cook Island L. tumuloides goes further in
reduction of apertural barriers.
Libera streptaxon (Reeve, 1852). Figure 179a-c.
Helix bursatella Gould, 1846. Proc. Boston Soc. Nat, Hist., 2, p.
175 - Tahiti and Moorea (parti; Gould, 1852. U. S. Explor.
Exped.. Wilkes, 12. pp. 51-53 (part); Gould, 1860. Atlas of Shells,
U. S. Explor. Exped.. Wilkes. pi. 4. figs. 52b. c. d. e.
Helix coarctata Pfeiffer. 1850 (Jan-June) (not Montagu, 1803. or
Deshayes, 1840). Proc. Zool. Soc. London. 1849. pp. 128-129 -
Tahiti. Society Islands; Pfeiffer. 1850 (April). Zeits. Malak.. 6. p.
74.
Helix streptaxon Reeve. 1852. Conchol. Icon.. Helix, pi. 112. fig.
641 — Tahiti. Society Islands.
Helix turricula Hombron and Jacquinot. 1852 (not Lowe. 1833).
Voy. PoL Sud. Astrolabe et Zelee. pi. 6. figs. 21-24 - Tahiti.
Society Islands: Rousseau. 1854. loc. cit.. 5. pp. 19-20.
Helix caivrnula Pfeiffer. 1853 (not Hombron and Jacquinot. 1852
or Lowe. 1833). Syst. Conchy 1. Cab.. I. 12. (31. pp. 297-298. pi.
125 (issued in 1852). figs. 29-31.
Helix (Libera} coarctata Pfeiffer (not Montagu or Deshayes).
Tryon. 1887. Man. Conchol.. (2l. 3. p. 71. pi. 13. figs. 78-80.
Libera streptaxon (Reeve). Ponsonby. 1910. Proc. Malacol. Soc.
London, 9. (1). pp. 41-42.
Diagnosis. — Shell larger than average, diameter 5.23-6.67 mm.
(mean 6.06 mm.), with 6V8 very tightly coiled whorls. Apex at most
barely protruding, upper spire flat, last two whorls descending
rapidly, body whorl drastically deflected beneath periphery of
penultimate whorL H/D ratio 0.434-0.616 (mean 0.542). Umbilicus
secondarily narrowed to form brood chamber by drastic inward
growth of baso-columellar margin, opening very narrow and
irregular, closure involving partial detachment of parietal wall,
umbilical opening contained 3.75-8.06 times (mean 6.45) in the
diameter. Postnuclear sculpture of prominent, broadly V-shaped,
widely spaced, protractively sinuated radial ribs, 36-55 (mean 46.4)
on the body whorl, whose interstices are 4-6 times their width, and
which become greatly reduced on shell base. Microsculpture of fine
radial riblets. twelve to twenty between each pair of major ribs, with
exceedingly fine and crowded spiral riblets. visible only under 96 x
magnification. Secondary sculpture of prominent, relatively crowded
spiral cords over entire shell surface. Sutures shallow, whorls evenly
rounded down to shallow supraperipheral sulcus, periphery protruded
into a broad threadlike keel that is acutely angled in juvenile
specimens, becoming right-angled with adulthood. Lower palatal
margin flatly rounded after su bperipheral sulcus. basal margin gently
and evenly rounded down to distinct sulcus before protruded baso-
columellar margin. Aperture subquadrangular, more strongly
rounded below than above protruded periphery, inclined about 35°
from shell axis. Parietal barriers 2, extending posteriorly to line of
vision: upper high and thin, markedly elevated and weakly expanded
above on posterior visible quarter, descending quickly to anterior
visible two-thirds that descends very gradually; 2nd parietal deeply
recessed, slightly shorter and higher than upper posteriorly, with
rather abrupt anterior descension to a short threadlike portion that
terminates about one-third to one-half length of upper parietal
within aperture in adults, extending to or beyond end of upper
parietal in juveniles. Columellar wall with broadly rounded,
relatively prominent, deeply recessed barrier reaching just to top of
columellar callus, rarely (4 per cent) absent. Palatal barriers 3.
moderately to deeply recessed, extending posteriorly about three-
sixteenths of a whorl: lower basal in position, elevated and bladelike.
flattened above on posterior third, with gradual anterior descension;
2nd palatal distinctly more elevated, flattened above on posterior
five-eighths, with more abrupt anterior descension. longer than 1st,
situated midway between 1st palatal and periphery: 3rd palatal
supraperipheral. deeply recessed, reduced in height, short, crescentic.
bladelike with very gradual anterior descension.
Libera recedens is the only other species having
the same abrupt body whorl descension. It differs from
L. streptaxon in its very numerous radial ribs (mean
178), distinctly more elevated spire and less prominent
peripheral sulci. Libera retunsa is much smaller, lacks
the lower parietal and usually all palatal barriers,
although it is very similar in sculpture.
Description. — Shell slightly larger than average, with 7 tightly
coiled whorls. Apex and early spire slightly depressed, main part of
spire flat, later whorls descending much more rapidly, body whorl
strongly deflected below periphery of penultimate. H/D ratio 0.434.
Embryonic whorls I1 4, sculpture of narrow and rounded radial
riblets. approximately equally spaced, crossed by very low and
crowded spiral riblets. Some ribs on the embryonic whorls appear
slightly larger than others, but there is no regular sequence.
Remaining whorls with very widely spaced. V-shaped, sinuately
protractive radial ribs, 46 on the body whorl, becoming reduced on
shell base, crossing rounded, equally spaced spiral cords that are
most strongly developed on shell base. Microsculpture of fine radial
riblets. 10-20 between each pair of major ribs and barely visible,
extremely crow-ded spiral riblets. Sutures moderately shallow, whorls
strongly rounded on upper spire, somewhat protruded, acuie keel,
evenly rounded below. Umbilicus with irregularly ovate opening,
constricted by inward growth of body whorl baso-columellar margin,
contained 3.75 times in the diameter. Part of closure effected by
detachment of lower parietal wall. Color yellowish-white wi:h many
414
SOLEM: ENDODONTOID LAND SNAILS
FIG. 179. a-c, Libera streptaxon (Reeve). Tahiti, Society Islands. Neotype of Helix streptaxon (Reeve, 1852). BPBM 167411; d-f, Libera
jacquinoti (Pfeiffer). Tahiti (?), Society Islands. BPBM 167409. Scale lines equal 1 mm. Microsculpture in c and d with spirals omitted. Drawings
by YK reproduced through the courtesy of Bernice P. Bishop Museum.
reddish tessellations. Aperture subquadrangular, inclined about 25°
from shell axis. Parietal wall with 2 barriers, extending posteriorly to
line of vision: upper lamellate for entire length, distinctly higher on
posterior quarter; lower with anterior half low and threadlike,
terminating opposite end of upper parietal. Columellar barrier high,
V-shaped, with gradual descension to top of columellar callus.
Palatal wall with 3 barriers, moderately recessed, extending
posteriorly three-sixteenths of a whorl: lower 2 high and bladelike,
with gradual anterior descension, subperipheral; upper much lower,
supraperipheral, with more gradual anterior descension. Height of
neotype 2.55 mm., diameter 5.88 mm.
Neotype. - Society Islands: Tahiti. BPBM 167411.
Range. — Probably Tahiti, Society Islands.
Material. - Tahiti (22 specimens, BPBM 167411,
FMNH 117009, SMF 165418, Paris); Moorea (1
specimen, BMNH 1908.7.2.41). "Marquesas" (1 speci-
men, FMNH 155933). No locality (2 specimens,
BMNH).
Remarks. — Since no type material could be
located in the British Museum (Natural History), I
have selected the illustrated specimen as neotype. The
general appearance is sufficiently similar to that of L.
retunsa that type selection seems required. Although
the neotype is not fully adult, its sculpture is well
preserved and shows clear differences from possibly
related species.
SYSTEMATIC REVIEW
415
FlG. 180. Umbilicus of Libera streptaxon showing exit hole from
brood chamber. FMNH 117009. (SH).
Umbilical closure is a modification of the pattern
seen in L. gregaria and L. recedens. It undoubtedly is
related to the depressed spire of L. streptaxon. For the
first whorl of closure, detachment of the parietal wall
is primarily responsible, but for the last whorl (or
fraction thereof) there is the normal slight intrusion of
the baso-columellar margin. In several specimens there
was clear evidence of the juvenile having eaten its way
out of the umbilical opening, leaving a distinct "notch"
in the columellar wall (fig. 180).
At first glance, the sculpture seems to be very
similar to that found in L. retunsa, but they are quite
different. In L. streptaxon there are 12 to 20
microradials (fig. 179c) between each pair of major ribs
and the very prominent secondary spiral cording
extends over the entire surface; in L. retunsa there are
only 5 to 10 (fig. 178d) much more widely spaced
microradials between each pair of major ribs and the
secondary spiral cording is much finer in character.
The effect is the same, but it has been arrived at
independently.
Apparently, L. streptaxon was not uncommon at
the time of its original description, but only scattered
specimens could be located at this time. None were
accompanied by exact locality data and the citations
of "Tahiti" and "Moorea" in early references provide
no data of significance. Garret t (1884, p. 34) had not
seen this shell and placed the references as synonyms
of what I call Libera dubiosa. These species are quite
different in appearance, although the original figures
could be misinterpreted. The habitat and exact
relationships of L. streptaxon are unknown.
Libera heynemanni (Pfeiffer, 1862). Figure 181
c-f.
Helix heynemanni Pfeiffer. 1862. Malak. Blatt.. 9. pp. 151-152 -
Tahiti. Society Islands; Pfeiffer. 18(i8. Monog. helic. viv., 5. p.
219; Pfeiffer. 1876. op. <•/'/.. 7. p. 255.
Pitys heynemanni (Pfeiffer). Pease. 1871. Proc. Zool. Soc. London.
1871, p. 475.
Pntula heinemanni (sic) (Pfeiffer). Schmeltz, 1874. Cat. Mus.
Godeffroy. 5. p. 93.
Libera heynemanni (Pfeiffer). Ancey. 1889. Le Naturaliste. (2), 11.
(59). pp. 190-191 (partly); Ponsonby, 1910. Proc. Malacol. Soc.
London. 9, (1). pp. 42-43.
Helix (Libera) heynemanni Pfeiffer, Tryon, 1887, Man. Conchol.,
(2). 3. p. 72 — description only, figure of garret liana.
Endodonta (Libera) heynemanni (Pfeiffer). Pilsbry. 1893, op. cit..
(2). 9. p. 24.
Diagnosis. - Shell large, diameter 5.23-8.43 mm. (mean 6.52
mm.), with 6'/i-8% normally coiled whorls. Apex and spire markedly
elevated, slightly to strongly rounded above, last whorl not to
strongly deflected beneath periphery of body whorl. H/D ratio 0.484-
0.578 (mean 0.538). Umbilicus narrowed to form brood chamber by
gradual inward growth of baso-columellar margin for last two
whorls, opening subcircular. contained 4.00-6.78 times (mean 5.05) in
the diameter. Postnuclear whorls macroscopically smooth, under
moderate to high magnification only low and very irregular growth
wrinkles visible. Sutures shallow, whorls flatly rounded down to
weak supraperipheral sulcus. periphery a very slightly protruded
threadlike keel, right-angled, lower palatal margin much more
strongly rounded than upper palatal down to sulcus before baso-
columellar margin. Walls of columella flat. Aperture subovate,
flattened laterally above protruded periphery, inclined about 30°
from shell axis. Parietal barriers 2, occasionally (1 of 15) with a
3rd, extending posteriorly to line of vision; upper high and bladelike,
expanded and more highly elevated on posterior third, with gradual
anterior descension; 2nd deeply recessed, equal in height or slightly
higher than posterior portion of upper, with rather sharp anterior
descension to parietal wall at approximately midpoint of upper
parietal, with or without a threadlike anterior extension to point
near termination of upper parietal: 3rd. when present, a lower
version of 2nd parietal. Columellar wall with a medial, very deeply
recessed, broadly rounded crescentic barrier that is not visible from
direct front view of aperture. Palatal barriers normally 3. occasion-
ally (2 of 15) a 4th one present, moderately recessed, extending
posteriorly about three-sixteenths of a whorl: lower two basal in
position, high and slender, flattened above on posterior half, with
progressively more gradual anterior descension. subperipheral; 3rd
supraperipheral. greatly reduced in height, short, deeply recessed,
elevated, and ridgelike; 4th, when present, subperipheral, with
relative positions of 1st and 2nd palatals shifted.
The complete absence of major radial sculpture
and secondary spiral cording combine with the very
large size to immediately identify this species. L.
incognata is similar in size and barriers, but has very
strong and prominent major radial ribbing above the
periphery. L. garrettiana, the only other species that
lacks major radial ribbing, has quite fine but promi-
nent secondary spiral cording and is much smaller in
size.
Type. — No potential type material was located.
Range. — Unknown, probably Tahiti, Society
Islands.
Material. - Tahiti (15 specimens, BPBM 170907-
8, Paris, Zurich, Brussels, Edinburgh).
Remarks. — None of the limited material seen
could be traced back to a possible association with
Pfeiffer. What I am interpreting as this species is a
comparatively large shell without any prominent
sculpture, and retaining well-developed apertural bar-
riers. Garrett (1884, p. 35) identified a much smaller
species which has prominent spiral cording and 4
palatals (see above as L. garrettiana) as heynemanni,
but the original description comes much closer to the
shells listed above. Since no localized or syntypic
material is known, I prefer not to select a type
specimen at this time.
FIG. 181. a-b, Libera incognata, new species. Tahiti (?), Society Islands. Holotype. BPBM 167407; c-f, Libera heynemanni (Pfeiffer).
c-d, gerontic shell. Society Islands. BPBM 170907; e-f, younger specimen. Tahiti, Society Islands. BPBM 170908. Scale lines equal 1 mm.
Drawings by YK reproduced through the courtesy of Bernice P. Bishop Museum.
416
SYSTEMATIC REVIEW
417
Libera incognata, new species. Figure 181 a-b.
Helix bursatella Gould, 1846, Proc. Boston Soc. Nat. Hist., 2, p.
175 - partly; Gould, 1852, U. S. Explor. Exped. Wilkes, 12, pp.
51-53 - partly; Gould, 1860, Atlas of Shells, U. S. Explor.
Exped. Wilkes, pi. 4, figs. 52, a; ?Pfeiffer, 1853, Syst. Conchyl.
Cab., I, 12, (3), p. 296, pi. 125, figs. 23-25 - probably (plate
issued in 1852).
Helix bursatella Reeve, 1852 (not Gould, 1846), Conchol. Icon.,
Helix, pi. Ill, fig. 635 - Tahiti, Society Islands.
Helix (Libera) bursatella Tryon, 1887 (not Gould, 1846), Man.
Conchol., (2), 3, p. 71, pi. 13, fig. 86 (copy of Conchol. Icon., pi.
Ill, fig. 635).
Diagnosis. — Shell very large, diameter 6.80-7.97 mm. (mean 7.30
mm.), with 7'/2-87/8 rather tightly coiled whorls. Apex and spire
markedly elevated, distinctly flattened and rounded above, last part
of body whorl descending slightly more rapidly in gerontic
individuals, H/D ratio 0.571-0.761 (mean 0.650). Umbilicus secondar-
ily narrowed to form brood chamber by inward growth of very
sharply edged baso-columellar margin, remaining opening subcircu-
lar, contained 3.80-7.27 times (mean 5.62) in the diameter.
Postnuclear whorls with prominent, broadly rounded, strongly
protractive, rather closely spaced radial ribs, 43-55 (mean 49.8) on
the body whorl, that become greatly reduced and irregular during
gerontic growth and are absent from base of shell. Microsculpture
reduced to very fine radial riblets, often interrupted by growth
wrinkles and irregularities on major ribs, surface of all material too
worn for detection of microspiral sculpture. No indication of
secondary spiral cording. Sutures shallow, whorls flatly rounded
down to weak supraperipheral sulcus, periphery broadly threadlike,
very weakly protruded, approximately right angled, lower palatal
wall flatly rounded down to weak sulcus before the extremely sharp
edged baso-columellar margin. Walls of columella flat and internally
with very thick callus. Aperture subquadrangular, more strongly
rounded below than above periphery, inclined about 25° from shell
axis. Parietal barriers 2, extending posteriorly to line of vision, rarely
with a weak accessory trace: upper parietal high and bladelike,
slightly higher and weakly expanded above on posterior third, with
rather sharp anterior descension just before termination; 2nd parietal
equally high and elevated on posterior third, descending moderately
to raised threadlike anterior half that may terminate in back of, at,
or beyond end of upper parietal. Columellar wall without (76.5 per
cent) or with (23.5 per cent) a low, broadly rounded and deeply
recessed lamellar ridge. Palatal wall normally (64.7 per cent) with
two deeply recessed, short, subperipheral barriers that extend about
one-eighth whorl posteriorly, frequently (23.5 per cent) with two
additional barriers, one sub- and the other supraperipheral, and often
(11.8 per cent) with only the additional supraperipheral: all palatals
slender and elevated, flattened above posteriorly, with relatively
gradual anterior descension.
Libera incognata is characterized by its domed
shape, very heavy radial sculpture above the periphery,
absence of major sculpture below the periphery,
absence of secondary spiral cording, and extremely
large size. Libera subcauernula from Rarotonga is
superficially similar, but has the sculpture greatly
reduced on the lower spire and, in specimens of similar
size, average l'/2 whorls less.
Description. — Shell very large, with 87/s tightly coiled whorls.
Apex and spire strongly elevated, rounded above, last one-eighth of
body whorl descending slightly. H/D ratio 0.761. Whorls somewhat
flattened laterally with only marginally indented sutures. Embryonic
whorls and early spire with sculpture eroded except for faint traces
of larger and smaller radial ribbing in the sutures. Postnuclear
whorls with low, broadly rounded, protractively sinuated radial ribs
that become greatly reduced on last part of body whorl. On upper
whorls ribs spaced 3-6 times their width. Microsculpture generally
eroded with only traces of exceedingly fine radial riblets remaining.
Base of shell with only irregular growth wrinkles. Body whorl
bluntly keeled, supra- and subperipheral sulci weak, flattened above,
rounded below. Color yellow-white, with numerous, broad, wine-red
flammulations. Umbilicus contracted to form brood chamber by
broad expansion of entire last whorl, baso-columellar margin sharp-
edged, opening ovate, contained 7.27 times in the diameter. Aperture
subquadrangular, flattened laterally, sinuately rounded below,
inclined about 40° from shell axis. Parietal wall with 2 moderately
high barriers, extending posteriorly to line of vision: upper broken
posteriorly, worn anteriorly; lower deeply recessed within the
aperture, half length of upper, moderately elevated. Columellar wall
with high white callus, no trace of a barrier. Palatal wall with 2
deeply recessed and moderately elevated, bladelike barriers, each
about one-eighth whorl in length. Height of holotype 5.43 mm.,
diameter 7.13 mm.
Holotype. - Society Islands: Tahiti. BPBM 167407
ex Fulton collection.
Range. — Unknown, but probably Tahiti, Society
Islands.
Paratypes. — Same as list of material.
Material. - Tahiti (9 specimens, BPBM 167407,
FMNH 117003, FMNH 156773, Zurich, Brussels). No
locality (8 specimens, BPBM 175610, SMF 165411,
BMNH 43.4.5.187-8).
Remarks. — Although apparently well known in
collections formed prior to 1860, this species does not
seem to have been collected by Garrett and has not
been taken subsequently. Presumably it lived on either
Tahiti or Moorea, but no data are available concerning
its habitat. No credence can be placed on the "Tahiti"
label in old collections, since this probably was copied
from the early references.
The apertural barriers, except for the columellar,
are like those of L. bursatella, and the sculpture of L.
incognata can be derived rather easily from that of L.
bursatella. I suspect that the former was (or is) a
Tahitian species. Possibly the variation in palatal
barriers is caused by age, since the larger individuals
had only 2 and the smaller, younger shells had 3 or 4
palatals. The very broad and irregular radial ribs are
quite different in appearance from those of L.
jacquinoti or the Cook Islands species, although the
rib spacing is very similar to the former.
Libera jacquinoti (Pfeiffer, 1850). Figure 179d-f.
Helix jacquinoti Pfeiffer. 1850 (Jan. -June), Proc. Zool. Soc.
London. 1849, p. 128 - Tahiti and Marquesas; Pfeiffer, 1850
(Apr.), Zeits. Malak., 6, pp. 73-74; Reeve, 1852, Conchol. Icon.,
Helix, pi. Ill, fig. 631; Pfeiffer, 1853, Syst. Conchyl. Cab., I, 12,
(3), pp. 296-297, pi. 125, figs. 26-28 (a different shell from the
type, plate issued in 1852).
Helix cavernula Hombron & Jacquinot, 1852, Voy. Pol. Sud,
Astrolabe et Zelee, Atlas, pi. 6 figs. 33-36 - Tahiti, Society
Islands; Rousseau, 1854, loc. cit., 5, pp. 17-18.
Helix (Libera) cavernula Hombron & Jacquinot, Tryon, 1887,
Man. Conchol., (2), 7, pp. 69-70, pi. 13, figs. 75-77 (copied from
Hombron & Jacquinot, loc. cit.}.
Helix (Libera) jacquinoti Pfeiffer, Tryon, 1887. loc. cit., p. 71 -
description only, figures are of excavata.
Libera jacquinoti (Pfeiffer), Ponsonby, 1910, Proc. Malacol. Soc.
London, 9, (1), p. 39.
Diagnosis. — Shell extremely large, diameter 7.45-9.28 mm.
(mean 8.46 mm.), with 67/s-9 normally coiled whorls. Apex and spire
418
SOLEM: ENDODONTOID LAND SNAILS
strongly and almost evenly elevated, at most very slightly rounded
above, body whorl sometimes deflected slightly beneath periphery of
penultimate whorl, H/D ratio 0.446-0.617 (mean 0.539). Umbilicus
secondarily narrowed to form brood chamber by gradual inward
growth of last whorl and one-quarter, resulting opening subcircular.
variable in size, contained 3.78-8.93 times (mean 6.49) in the
diameter. Postnuclear whorls with prominent, broad but sharply
defined, strongly protractively sinuated radial ribs that generally
become moderately to greatly reduced on body whorl, an estimated
47-67 (mean 55.0) on adult specimens, whose interstices are 2-3 times
their width. Microsculpture of very fine radial riblets, more than 10
between each pair of major ribs, crossed by extremely fine and
crowded spiral riblets. Sutures very shallow, whorls flatly rounded
down to broad and shallow supraperipheral sulcus, periphery quite
strongly protruded into a sharp threadlike keel, generally with an
even shallower subperipheral sulcus, lower palatal and basal margins
gently and evenly rounded down to weak sulcus just before very
sharp edged baso-columellar margin. Aper'ure subovate. more
strongly rounded below than above markedly protruded periphery,
inclined about 40° from shell axis. Parietal barriers 2, extending
posteriorly to or slightly beyond line of vision: upper very high and
slender, slightly more elevated above on posterior visible third, with
very gradual anterior descension until just before termination; 2nd
parietal equally high on posterior third, with rather sharp anterior
descension to point opposite midpoint of upper parietal, with or
without a threadlike anterior extension reaching slightly beyond
termination of upper parietal. Columellar wall with a broadly
rounded, relatively low, very deeply recessed crescentic barrier, with
very gradual anterior descension and slightly slanting upwards across
top of columellar callus. Palatal barriers normally 4, rarely (3.8 per
cent) with upper absent, deeply recessed, extending posteriorly about
three-sixteenths of a whorl: lower basal in position, generally slightly
reduced in height, with relatively sharp anterior descension; 2nd and
3rd subperipheral, slightly to moderately higher than 1st, flattened
above on posterior half, with progressively more gradual anterior
descension; 4th supraperipheral. situated midway between periphery
and parietal-palatal margin, low and threadlike to moderately
elevated, bladelike, with very gradual anterior descension.
The extremely large size, prominent radial ribbing
above the periphery, retention of 4 palatal barriers,
and relatively straight-sided spire combine to separate
Libera jacquinoti from all other known species. L.
incognata appears at first glance to have similar
sculpture, but is a much more elevated and smaller
shell with the ribbing much coarser and the individual
ribs more broadly rounded. L. fratercula is at once
separated in having the radial ribbing retain its
prominence below the body whorl periphery.
Description. — Shell very large, with 8 moderately tightly coiled
whorls. Apex and spire strongly and almost evenly elevated, sides
only slightly convex, H/D ratio 0.545. Apical whorls 1%, sculpture
mostly eroded with traces of broadly rounded, low radial ribs visible
in the suture. Postnuclear whorls with moderately widely spaced,
broad, slightly protractively sinuated radial ribs, 62 on the body
whorl, whose interstices are I1 4-3 times their width, and which are
slightly to moderately expanded on crossing periphery. Micro-
sculpture of extremely fine and crowded radial riblets crossed by
barely visible spiral riblets. Major ribs finely denticulate periphery,
moderately to strongly reduced in prominence on base of shell.
Sutures very shallow, whorls flatly rounded above with prominent
supraperipheral sulcus. Periphery protruded into acutely angulated
keel with only slightly less prominent subperipheral sulcus and flatly
rounded basal margin. Color faint yellowish-white, with irregular,
zigzag, reddish flammulations above, absent from base of shell.
Umbilicus small, strongly constricted by diagonal inward growth of
last whorls, opening nearly circular, contained 6.70 times in the
diameter. Aperture subquadrangular with peripheral keel and flatly-
rounded basal margin, inclined about 20° from shell axis. Parietal
barriers 2. extending posteriorly about one-quarter whorl: upper a
narrow lamellate ridge gradually becoming quite high posteriorly,
with very slow descension over anterior two-thirds, moderately rapid
descension at anterior edge; 2nd parietal less than two-thirds length
of upper, deeply recessed, equally high and narrow posteriorly, with
sharp anterior descension. Columellar wall with heavy white opaque
callus and prominent, ridgelike, deeply recessed columellar barrier
visible only at an extreme angle. Palatal barriers 4, extending slightly
more than one-eighth whorl: lower palatal a small, lamellate ridge
near basal margin; 2nd much higher, bladelike posteriorly, with very
gradual anterior descension; 3rd intermediate in length, between 1st
and 2nd; 4th a narrow, V-shaped, supraperipheral ridge situated just
above supraperipheral sulcus. All palatals moderately to deeply
recessed within aperture. Height of lectotype 4.78 mm., diameter 8.76
mm.
Lectotype. - "Society Islands." BMNH 1962707/1
ex Hugh Cuming.
Range. — Unknown, but most probably Tahiti or
Moorea, Society Islands.
Paratypes. - BMNH 1965707/2-3.
Material. • "Society Islands" (3 specimens,
BMNH 1965707/1-3). "Tahiti" (17 specimens, BPBM
167409, FMNH 46349, Paris, AMS). "Tubuai" (3
specimens, FMNH 156769, AMS C28645). "Marquesas"
(1 specimen, BPBM 189941). Unknown (5 specimens,
FMNH 117316, AMS).
Remarks. — None of the specimens were accom-
panied by meaningful locality data and the range of
Libera jacquinoti remains unknown. Its superficial
appearance is very much like the Cook Islands L.
fratercula and L. subcavernula, but the great reduc-
tion in ribbing below the body whorl periphery,
narrower and more sharply defined radial ribs, and
great size (tables C, CVI) are more similar to the
Society Islands species. This is by far the largest
species of Libera. Eventual discovery that it is from a
locality other than the Cook or Society Islands would
not surprise me.
Gambiodonta grandis from Mangareva is similar
in general appearance, but the totally different form of
umbilical closure and greatly increased number of
apertural barriers found in the latter immediately
differentiate the two species. G. grandis also is much
larger at the same whorl count.
Libera fratercula (Pease, 1867)
More material was available for this species than
for any other endodontid studied. Besides the 2,899
individuals cited below, 865 vaguely localized shells in
older collections were quickly inspected for peculiar-
ities, but not assigned to subspecific units or
measured. Additional thousands of specimens are
present in the mixed Pease material at the Museum of
Comparative Zoology.
A detailed discussion of population size and
structure in the Rarotonga shells is presented else-
where (Solem, 1969a), together with a fuller analysis of
variational trends.
SYSTEMATIC REVIEW
419
,
Although Garrett (1881, p. 392) reported this
species from Aitutaki, I saw no material from that
island. Material from Mauke, Atiu, Mangaia, and the
satellite islands of Rarotonga agreed rather closely in
respect to size, shape, and sculpture (tables CIV, CV).
Those from Rarotonga are significantly larger (table
CIV), generally have fewer palatal barriers, and often
a prominent columellar. With some hesitation, this
difference is recognized as subspecific, the Rarotonga
populations being described as a new subspecies,
Libera fratercula rarotongensis.
Apparently, Libera fratercula is unique within the
family as to its habitat. It lives at low elevations very
near the shore and persists under obviously disturbed
ecological conditions. It has been collected a few feet
above the tide mark among coral boulders. In this
habitat on Rarotonga it reaches a mean population
density of 39.87 ±3.49/ft.-, with an estimated total
population in one polony of 43,000,000 ± 3,770,000. In
this relatively exposed habitat, it is subject to
fluctuating moisture conditions and shows consid-
erable local variation (Solem, 1969a). There are no
inland records for L. fratercula. Accidental transport
by waves during severe storms may account for its
wide distribution in the Cook Islands.
Probably because of its habitat among coral
boulders, with an essentially unlimited supply of
calcium, L. fratercula has adopted its peculiar mode of
releasing young from the brood pouch. Full details are
given in Solem (1969a), but here it can be summarized
briefly. During narrowing of the brood chamber, the
animal gradually vacates the upper spire whorls, filling
in behind itself with calcium. The upper spire becomes
solid calcium while the eggs are in the brood chamber.
After the young hatch, they chew their way into the
sides of the umbilicus and eventually create an apical
or subapical hole through which they exit. What
percentage of the adults die before this process is
completed remains unknown. Of the semi-quantitative
samples (Stations R-l through R-10) taken on Rar-
otonga, 44.5 per cent of live collected adults had
hatched young in their brood chambers. An additional
27 specimens (4.3 per cent of 623 adults), which were
collected alive, had the apex missing and the brood
chamber considerably "chewed." It is possible that
some of the damage occurred in the preservative or
during handling, but most of the specimens represent-
ed post-reproductive material that had survived exiting
of the young.
Both of the inland Rarotonga species, Libera
subcavernula and L. tumuloides, are obvious deriva-
tives of L. fratercula. Distinguishing features are
mentioned under the diagnoses of these species. Of the
other Libera, only L. jacquinoti and L. incognata
might be confused. The former is much larger, has
more widely spaced ribbing which is greatly reduced
below the body whorl periphery and has 3 or 4
palatals. L. incognata agrees more closely in barriers,
but has fewer and broader major ribs (mean 49.8) and
is larger in size.
Libera fratercula fratercula (Pease, 1867). Fig-
ure 182e-f.
Helix nculptiliK Pease. 1864 (not Bland. 1858), Proc. Zool. Soc.
London. 1864. pp. 669-670 - Mangier (error for Mangaia, Cook
Islands); Pfeiffer, 1868, Monog. helic. viv.. 5. p. 217.
Hell\ fratercula Pease. 1867, Amer. Jour. Conchol., 3, (1), p. 104 -
new name for sculptiliK Pease, 1864, not Bland, 1858; Pfeiffer,
1876, Monog. helic. viv., 7, p. 253 — Gambier Islands (error,
possibly based on a Gambiodonta) .
Libera fratercula (Pease). Garrett. 1881. Jour. Acad. Nat. Sd.,
Philadelphia. 8, (4). p. 392 - Aitutaki and Atiu. Cook Islands;
Ponsonby. 1910. Proc. Malacol. Soc. London. 9. (1). pp. 38-39.
Diagnosis. — Shell of average size, diameter 4.84-6.54 mm.
(mean 5.60 mm.), with 5\*>-l\ rather tightly coiled whorls. Apex and
spire strongly elevated, normally rounded or slightly flattened above,
last whorl rarely descending more rapidly. H/D ratio 0.475-0.696
(mean 0.570). Umbilicus strongly narrowed to form brood chamber
by gradual inward growth of baso-columellar margin over last two
whorls, opening circular or irregularly subcircular. contained 5.20-
13.0 times (mean 7.40) in the diameter. Postnuclear whorls with very
large, broadly rounded, strongly protractively sinuated radial ribs,
65-112 (mean 81.5) on the body whorl, whose interstices are about
equal to their width. Microsculpture of extremely fine radial riblets,
five to eight between each pair of major ribs, crossed by slightly finer
and more crowded spiral riblets. both generally worn off peripheral
portion of major ribs. Sutures shallow, whorls strongly rounded
down to very deep supraperipheral sulcus, periphery a markedly
protruded threadlike keel with a deep subperipheral sulcus, lower
palatal and basal margins rather strongly and evenly rounded down
to baso-columellar margin which is marked by only a weak sulcus.
Aperture subovate. strongly rounded above and below markedly
protruded periphery, inclined about 35° from shell axis. Parietal
barriers 2. extending posteriorly to line of vision; upper slightly more
elevated and weakly expanded above on posterior third, with very
slight anterior descension until just before termination, when barrier
descends abruptly; 2nd parietal normally recessed two-thirds to one-
half the length of upper, equally high and expanded on posterior
elevated part with rather abrupt descension to point just behind or
in front of midpoint of upper parietal, sometimes with a weak
anterior threadlike extension that rarely reaches end of upper
parietal. Columellar wall slightly convex inside aperture, with a
heavy callus, but no noticeable columellar barrier from apertural
view, occasionally a vague central elevation visible by extreme tilting
of aperture. Palatal barriers normally 4. rarely (5 per cent) with
supraperipheral trace absent, deeply recessed, extending posteriorly
more than one-eighth whorl: lower basal in position, ridgelike,
partly to completely hidden in apertural view by strong columellar
callus, with very gradual anterior descension to point just behind top
of baso-columellar callus margin; 2nd moderately elevated, weakly
expanded above on posterior third, with very gradual anterior
descension. much higher than 1st; 3rd midway in height between 1st
and 2nd, subperipheral, with even more gradual anterior descension;
4th, when present, supraperipheral, a low to moderately elevated and
deeply recessed threadlike trace.
Libera fratercula fratercula differs on the average
in size and spire elevation from L. fratercula raroton-
gensis, but is systematically differentiated by retaining
3 subperipheral palatal barriers, and in having no
conspicuous columellar barrier. The other Cook Is-
lands species differ in their reduced major radial
ribbing and less pronounced peripheral protrusion,
while the very large L. jacquinoti also differs in its
greatly reduced radial ribbing.
CO
c-
<N
o £
I ~
00
•v.
CO
o
oo
CD
o as
*w ^f
Q
•«v.
IO
o
co"
in
1O
o
cr
to"
3l
CO
1C
C-
CM
IO
;D
CM
IO,'
CD
CD'
i
fir
U
1
O
CD
.-H
c-
EH
<
E
a
1C
IO
*
K
K
S
CM
«
CD
rt £
gPE
2^
c~ :s
pq
M 5?
ST
5"
6?
^ 4i
CO
O3
•^t
rH
£ 'o
CO
H ^ '
co'
?'
CD
s s
CO
CO
c
EH S in
<£ oo
H'^^ CM
QJ , ,
CO
CM'
CM'
T-I
co"
w >
•3 "
K n IH
c
I-H
CM
of
CO
ca 3
^ CM'
CO
co"
•*"
1-1 T~l
CO
C—
O
CO
t*fc
^ S
1
(T-
CD
1—1
^
M CTJ
T-H
iO
LC
CD"
in
£ C
J>"
E
O '
C CO
CO i
CO r
CD rH
CO fH
o
CM T3
H
^
i-l CN
i-l CD
0 CO
rH CO
W
i-q
A
S
-H •—'
i-l
0
O CO
CO
0* CO*
CD
CO
O CO
<N
<N
Z (2
• •
m
•
T-H
T-H
vM
T-H OJ
T-l 03
00 i
<n -CO
S T-H CO
O
00
00
c-
o
CM i-H
(N I
. CM
i-l C-
-H -^
CO
CO
. CD
<M CO
-H ^^
O
CO
OO
.2
<
I
n)
00
c
o
420
TABLE CV. - LOCAL VARIATION IN LIBERA FRATERCULA
Name
Number of
Specimens
Examined Height
Diameter
H/D Ratio
Whorls
D/U Ratio
fratercula fratercula
Atiu
BPBM 94950 15
2. 86±0.053
(2.55-3.20)
5.21±0.037
(4.90-5.42)
0.549*0.0088
(0.494-0.620)
6 1/8-
(5 1/2-6 1/2)
7.15*0.245
(5.71-8.77)
Mauke
BPBM 95162 20
3.00±0.032
(2.81-3.20)
5.49±0.037
(5.16-5.75)
0.547*0.0036
(0.524-0.578)
6 1/8*
(6-6 1/2)
Mangaia
BPBM 97492-3 15
2. 92±0.068
(2.55-3.40)
5.36i0.076
(4.84-5.88)
0.544*0.0067
(0.512-0.598)
6 1/8+
(5 7/8-6 1/2)
BPBM 97477 23
3.27±0.056
(2.81-3.66)
5.62i0.043
(5.23-5.95)
0.580i0.0069
(0.529-0.647)
6 5/8+
(6 1/4-7)
7.36*0.159
(6.14-9.45)
BPBM 97436-7 16
3.57±0.097
(3.07-4.44)
5.99i0.060
(5.56-6.54)
0.594*0.0115
(0.527-0.680)
7 1/2-
(6 1/4-7 3/4)
7.83*0.255
(6.07-9.78)
BPBM 97556 17
3.58*0.052
(3.07-3.99)
5.93^0.055
(5.62-6.34)
0.604*0.0068
(0.534-0.651)
7-
(6 1/2-7 1/8)
" Mangier"
BMNH 1965705/1-5 5
Satellite islands
of Raratonga
FMNH 152745 90
Sta. R-18
2.85±0.161
(2.48-3.20)
3.50±0.034
(2.91-4.46)
5.49±0.239
(4.77-6.08)
5.71*0.034
(5.05-6.47)
0.518*0.0112
(0.475-0.539)
0.607*0.0076
(0.541-0.674)
6 +
(5 1/2-6 1/2)
6 5/8+
(4 3/8-7 1/4)
6.93*0.452
(6.08-8.28)
FMNH 153784 19
Sta. R-19
3.60±0.067
(2.91-4.08)
5.74+0.097
(4.79-6.53)
0.614±0.0089
(0.514-0.687)
6 3/4-
(5 1/2-7 1/4)
FMNH 152742 106
Sta. R-17
3.80±0.022
(3.36-4.53)
6.17±0.021
(5.69-6.99)
0.617*0.0025
(0.559-0.690)
7-
(6 1/2-7 5/8)
fratercula rarotongensis
4.08i0.102
(3.66-4.97)
6.41±0.109
(6.08-7.65)
0.635±0.0091
(0.582-0.683)
7-
(6 1/2-7 1/2)
7.04*0.291
(4.26-9.36)
BPBM 167428 (pre-1890) 14
BPBM 95356-7 (1929) 21
3.96±0.064
(3.53-4.64)
6.34±0.038
(6.01-6.60)
0.623*0.0090
(0.571-0.725)
7-
(6 3/8-7 1/2)
7.44*0.300
(6.12-8.91)
BPBM 95363, -5, -8 14
(1929)
4. 20±0.096
(3.59-4.77)
6.49±0.097
(6.01-7.19)
0.647*0.0104
(0.573-0.717)
7 1/4-
(6 5/8-7 3/4)
7.51i0.222
(6.12-9.00)
FMNH 144514 -5 40
Sta. 1, 1964)
3.89±0.063
(3.13-5.00)
5.54±0.038
(5.07-6.05)
0.702*0.0093
(0.583-0.844)
6 7/8-
(6-7 3/8)
6.93±0.231
(5.09-13.38)
FMNH 144556. -8 35
Sta. 6. 1964
4.72*0.077
(3.88-5.39)
6.92±0.055
(6.25-7.57)
0.682±0.0088
(0.593-0.788)
7 3/4-
(6 7/8-8 3/8)
7.97*0.148
(6.67-10.40)
FMNH 144557 170
Sta. 6. 1964
FMNH
Sta. R-l - R-10 367
4.58±0.037
(3.49-5.72)
4.24*0.017
(3.23-6.18)
6.75*0.023
(5.92-7.50)
6.62±0.001
(5.43-8.15)
0.678*0.0041
(0.540-0.821)
0.641*0.0025
(0.519-0.813)
7 5/8+
(6 1/2-8 1/2)
7 1/2-
(6-8 3/4)
7.69*0.071
(5.11-9.82)
421
a-c,e
d,f
f
FIG. 182. a-d, Libera fratercula rarotongensis, new subspecies. Tupapa, Rarotonga, Cook Islands. Holotype. BPBM 95386; e-f, Libera
fratercula fratercula (Pease). South of Oneroa, Mangaia, Cook Islands. BPBM 97503. Scale lines equal 1 mm. (SH).
4-22
SYSTEMATIC REVIEW
423
Description. — Shell of average size, with 6M> moderately tightly
coiled whorls. Apex and spire strongly elevated, rounded above, last
whorl not descending more rapidly, H/D ratio 0.539. Embryonic
whorls 1"2, sculpture of moderately prominent, rounded radial ribs,
eroded on upper portion. Postnuclear whorls with prominent,
broadly rounded, protractively sinuated radial ribs, about 84 on the
body whorl, whose interstices are almost the same as their width,
and which become more broadly rounded on crossing periphery.
Microsculpture occasionally visible as very fine radial riblets crossed
by much finer and more crowded spiral riblets. Major ribs
denticulate periphery of body whorl upon crossing, becoming slightly
narrower and less prominent on shell base. Sutures shallow, whorls
flatly rounded above with deep supraperipheral sulcus. Periphery a
protruded, acutely rounded keel with slight subperipheral sulcus.
base of shell flatly rounded. Umbilicus minute, strongly constricted
by inward growth of last whorl, contained 8.28 times in the diameter.
Color light yellowish-white, with faint, irregular, reddish maculations
on upper spire. Aperture subquadrangular with beaklike carina and
gently rounded basal margin. Parietal barriers 2, extending
posteriorly one-quarter whorl: upper narrow, bladelike, sharply
descending anteriorly, weakly expanded and with very fine serrations
on posterior half; lower parietal less than two-thirds length of upper,
deeply recessed within aperture, higher posteriorly with much more
gradual anterior descension. Columellar wall with heavy opaque
white callus extending slightly onto basal margin. Palatal barriers 4,
deeply recessed, extending about one-eighth whorl: lower basal in
position, partially hidden by anterior extension of callus, a very low
lamellar ridge; 2nd high, bladelike, flattened above posteriorly, with
gradual anterior descension; 3rd of same length and appearance as
2nd, but slightly lower in height; upper a low, rounded, V-shaped
ridge, situated just above supraperipheral sulcus. Height of lectotype
3.21 mm., diameter 5.95 mm.
Lectotype. — Cook Islands: Mangier ( = Mangaia).
BMNH 1962705/1 ex Hugh Cuming, W. H. Pease.
Range. — Mauke, Aitutaki, Atiu, Mangaia and
satellite islets of Rarotonga, Cook Islands.
Paratypes. - BMNH 1962705/2-5, BPBM 1399.
Material. — Mangaia (8 specimens, BPBM 97600,
BPBM 97560, FMNH 117047): south of Oneroa, 200
yd. inland at 50 ft. elevation (162 specimens, BPBM
97477-83, collected December 22, 1929 by P. H. Buck);
south of Oneroa, 200 yd. inland at 50 ft. elevation (213
specimens, BPBM 97490-8, BPBM 97503-4 collected
December 16, 1929 by P. H. Buck); north of Oneroa,
200 yd. inland at 50 ft. elevation (115 specimens,
BPBM 97435-40 collected December 16, 1929 by P. H.
Buck); northwest coast, 200-850 yd. inland at 50-150 ft.
elevation (2 specimens, BPBM 97430 collected by P. H.
Buck on December 14, 1929); north of Orongo, 200 yd.
inland at 20 ft. elevation (77 specimens, BPBM 96555-8
collected February 3, 1930 by Peter H. and Margaret
Buck); Orongo, 150 yd. inland at 50 ft. elevation (153
specimens, BPBM 97618-23 collected February 10,
1930 by P. H. Buck); Orongo, 400 yd. inland at 50 ft.
elevation (22 specimens, BPBM 97625-6).
Mauke (7 specimens, BPBM 95272, AMS C18487):
Taunganui, 300-600 yd. inland at 50-70 ft. elevation
(163 specimens, BPBM 95162-3, BPBM 95211-3,
BPBM 95285, BPBM 95596 collected September 9 to
November 25, 1929); Utu, 100 yd. inland at 50 ft.
elevation (58 specimens, BPBM 95229-31 collected
September 15, 1929 by P. H. Buck).
Atiu (3 specimens, BPBM 87406): Taunganui
track, one-half mile inland at 30-70 ft. elevation (197
specimens, BPBM 94950-4, BPBM 94958-9 collected
August 15, 1929 by P. H. Buck); Torapaka, one-
quarter to one-half mile inland at 30-70 ft. elevation
(43 specimens, BPBM 94973-4, BPBM 94979, BPBM
94995-7, BPBM 95016-7 collected August 23, 1929 by
P. H. Buck); Matai track, one-quarter mile inland at
30 ft. elevation (2 specimens, BPBM 95116 collected
September 1, 1929 by P. H. Buck); Mokoero, one-half
mile inland at 30 ft. elevation (134 specimens, BPBM
95123, BPBM 95135-40).
Satellite islands of Rarotonga: Oneroa, Station R-
19 (29 specimens, FMNH 153784); Motutapu, Stations
R-17 - R-18 (307 specimens, FMNH 152742-5).
Inadequate data or "Mangier" (50 specimens,
BMNH 1962705/1-5, DMW 8840, FMNH 46616,
FMNH 73868, FMNH 90614, FMNH 90631, FMNH
91760).
Remarks. — The remnant of the type set
preserved in the British Museum (BMNH 1965705/1-
5) contains slightly subadult examples. These were
obtained by Pease from a Dr. Dean (Garrett, 1881, p.
392). Although Garrett collected many specimens from
Atiu, Aitutaki, Mauke, and Mangaia, no museum
material from this period retained sufficient geographi-
cal data to warrant restudy. Garrett (Zoc. cit.) stated
that the Rarotonga examples (here described as L. f.
rarotongensis) were larger and with a more elevated
spire; the Mangaia specimens a "uniform luteous horn
color"; and the Atiu examples smaller, darker and
frequently variegated with reddish brown. Partial
analysis of the material collected by the Bucks on
Atiu, Mangaia, and Mauke in 1929-1930 showed mean
size differences between the islands (table CIV) and
moderate to considerable variation between popu-
lations (table CV). The Atiu populations are smaller,
but there is no significant difference between the
Mauke and Mangaia populations. In general, the
reported color differences were confirmed, but no
statistical analysis of color variation was attempted.
Specimens from the low coral islets of Motutapu
and Oneroa off the coast of Rarotonga (Stations R-17,
R-18, R-19) had the barrier number (4 palatals) and
were closer to the size range (table CIV) of the
nominate race. They are classified with this subspecies,
rather than with the Rarotongan race.
A scatter diagram of ribs and ribs/mm, (fig. 183)
shows the essential similarity of the various popu-
lations, with only a slight offset distinguishing the
smaller Atiu and larger Rarotonga shells.
Specimens from both Mauke (BPBM 95162) and
Mangaia (BPBM 7492) were dissected and found to
agree with the structures of L. f. rarotongensis in
everything except penial length. The penes were 2.5-2.8
mm. long in the Mauke and Mangaia examples,
compared with 3.3-3.5 mm., in the Rarotonga shells.
in
<
i-
0
*
T-
5 * **S£
in
o
T-
i and Atiu.
0 k « <
cc < 2 ^ cc
UJ
I
5
cc
u- *
0
0
1
1
< * <
£ <
CO
in
0)
c
J
^
• o *
1
o« • o <
1
o
B
0
fc
< *
05 CO
CO
"o
^<J ^ ^
••
tn
cc
^O
5
<<<
in
1
.^_
00
.=
0 *
S
< *
6
o • « ^ «o o*
1
• 0 «<^
0
-g
CO
< <1<S *
00
1
CO
o
'I
• << o *
1
• < • o <
I
3 * < <,*
in
t^
1
• 0
1
< *
1
0*
O
i
o *
• 0
• o o *
1 i ! 1 I i L__I
in
CD
in q in o in p in
co cd in m ^ ^ w
424
SYSTEMATIC REVIEW
425
The internal pilaster structure was identical in the
several populations.
Libera fratercula rarotongensis, new sub-
species. Figures 172c-g; 182a-d.
Pitys fratercula Pease, 1871, Proc. Zool. Soc. London, 1871, p. 475
— Rarotonga. Cook Islands.
Helix (Libera} fratercula (Pease), Tryon, 1887, Man. Conchol., (2).
3, p. 70, pi. 13, figs. 64-66.
Endodonta {Libera} sculptilis Pease (not Bland). Pilsbry, 1893, op.
cit., (2), 9, p. 24 - corrected on p. 339 (1895) to fratercula.
Diagnosis. — Shell large, diameter 5.43-8.15 mm. (mean 6.59
mm.), with 6-8% rather tightly coiled whorls. Apex and spire strongly
elevated, slightly rounded above, last whorl rarely descending more
rapidly. H/D ratio 0.519-0.844 (mean 0.656). Umbilicus secondarily
narrowed to form brood chamber by gradual inward growth of last
two whorls, resulting opening usually quite narrow, circular or
subcircular in outline, contained 4.26-13.4 times (mean 7.55) in the
diameter. Postnuclear whorls with prominent, broadly rounded,
strongly protractively sinuated radial ribs, 66-105 (mean 83.0) on the
body whorl, whose interstices are about equal to their width.
Microsculpture of fine radial riblets, five to eight between each pair
of major ribs, crossed by exceedingly fine and crowded spiral riblets.
Sutures shallow, whorls strongly rounded down to deep and narrow
supraperipheral sulcus. periphery strongly protruded into a thread-
like keel with shallower subperipheral sulcus. lower palatal wall
strongly rounded down to flattened basal margin with very weak
sulcus just before knife-edge baso-columellar margin, columellar wall
inside umbilicus flattened. Aperture subovate, strongly rounded
above and below markedly protruded periphery, inclined about 35°
from shell axis. Parietal barriers 2, extending posteriorly to line of
vision: upper moderately elevated, slightly higher above on posterior
third with very gradual anterior descension until just before
termination; 2nd parietal recessed two-thirds to three-quarters length
of upper, markedly reduced in height, very weakly expanded above
posteriorly, with rather sharp anterior descension, occasionally in
juveniles with a threadlike anterior trace reaching almost to end of
upper parietal. Columellar wall slightly convex inside aperture,
heavily callused. either with or without a low to moderately
prominent, very deeply recessed barrier that is barely visible by
extreme tilting of aperture. Palatal barriers 2, very deeply recessed,
extending posteriorly about one-eighth whorl, subperipheral; lower
occupying position of 2nd palatal in nominate subspecies, a raised
ridgelike barrier with very gradual anterior descension: 2nd occupy-
ing position of 3rd palatal in nominate subs|>ecies, equal to. slightly
larger than, or slightly smaller than 1st palatal, usually with more
gradual anterior descension.
Libera fratercula rarotongensis is immediately
separable from the nominate race in lacking the 1st
and 4th palatals. Usually it has a columellar barrier.
Size differences are considerable, although overlap
exists. Libera subcavernula has the sculpture greatly
reduced on the spire and absent on the lower whorls,
while the periphery is much less strongly protruded.
Libera tumuloides differs in having no major radial
sculpture and retaining only 1 parietal and 1 palatal
barrier in adult specimens.
Description. — Shell relatively large, with 7'/s moderately tightly
coiled whorls. Apex and spire strongly elevated, slightly rounded
above, last whorl not descending more rapidly, H/D ratio 0.626.
Embryonic whorls l'/2, sculpture partially eroded with remnants of
fine radial ribs persisting near suture. Postnuclear whorls with
broadly rounded, prominent, protractively sinuated radial ribs, about
90 on the body whorl, whose interstices are equal to or slightly
narrower than their width. Microsculpture of fine radial riblets
crossed by exceedingly fine and crowded spiral riblets continuing
onto and on top of the major radial ribs. Major ribs finely
denticulating peripheral keel on crossing, somewhat reduced in
prominence on shell base. Sutures shallow, with denticulated edge,
whorls strongly rounded above with deep, concave sulcus above
periphery, weaker sulcus below. Body whorl with protruded
denticulated carina. Umbilicus strongly constricted by expansion of
last whorl-and-one-half, opening narrow, somewhat irregular in
shape, contained 8.25 times in the diameter. Color a light yellow-
white, with a few brownish tessellations on the upper spire, fading
out after 5th whorl. Aperture subquadrangular with protruded
beaklike carina, with evenly rounded basal margin, inclined about
35° from shell axis. Parietal barriers 2, extending posteriorly to line
of vision: upper moderate in size, becoming slightly higher on
posterior half; lower deeply recessed, becoming lamellate posteriorly,
about half length of upper. Columellar wall with heavy thick white
callus, a deeply recessed, low columellar barrier barely visible within
aperture, gradually descending behind columellar callus. Palatal
barriers 2, extending slightly less than one-eighth whorl, moderately
elevated with gradual anterior descension, both subperipheral in
position and very deeply recessed. Height of holotype 4.05 mm.,
diameter 6.47 mm.
Holotype. — Cook Islands: Rarotonga, 200 yd.
inland from Tupapa at 10 ft. elevation. Collected by
Margaret Buck on October 4, 1929. BPBM 95368.
Range. — Rarotonga, Cook Islands, but not the
small satellite islands of Oneroa and Motutapu.
Paratypes. — Same as list of material.
Material. — Rarotonga (46 specimens, BPBM
167428, FMNH 90630): 200 yd. inland at 10 ft.
elevation, Tupapa (178 specimens, BPBM 95356-68
collected by Margaret Buck on October 4, 1929); 1.6-
2.8 miles east (Stations R-l through R-10, R-14, R-15)
of Avarua (930 specimens, FMNH 152743-4, FMNH
153372-4, FMNH 153376-9, FMNH 153393, FMNH
153418, FMNH 153421 collected by Laurie Price in
November 1965); Avarua (Stations 1, 6) and Avatiu
Harbour area (247 specimens, FMNH 144514-5,
FMNH 144556-8 collected by Laurie Price in October
to November, 1964). Cook Islands (13 specimens,
FMNH 91073, FMNH 91842).
Remarks. — A particularly large colony of Libera
fratercula rarotongensis is found 1.6-2.8 miles east of
Avarua on both sides of the main road. Except for
scattered houses, where the coral boulders and part of
the undergrowth have been cleared away, the colony is
continuous. It starts just inside the vegetation above
the storm high-tide mark and continues through the
coral boulder zone, fading out about 150 yd. inland,
congruent with the end of the boulders. The vegeta-
tion consists of typical lowland scrub, coconut palms,
and a few large trees. Samples of all living individuals
within a 15-in. -square quadrat were taken at 200 yd.
intervals. The mean density of living individuals was
39.87 ±3. 49 per sq. ft. The total population of the
colony, just between the main road and the high tide
mark, is estimated at about 43,000,000 living snails.
Full discussion of variation in this colony is given in
Solem (1969a). Summary measurements are given in
Table CV. The 1964 locality, Station 6, is from part of
this same colony.
426
SOLEM: ENDODONTOID LAND SNAILS
For comparison, data on material from pre-1890
collecting (BPBM 167428) and two segregates from the
1929 collecting (BPBM 95356-7 and BPBM 95363, -5,
-8) are presented in Table CV. It is obvious that there
are no significant differences between the populations
from different time intervals. There is, however, a
significant difference between material from the 1964
collection at Station 1 (FMNH 144514-5) and the
remaining samples discussed above. The Avatiu Har-
bour examples are much smaller and slightly higher,
reaching the diameter and whorl count, but not the
height or H/D ratio, range of the nominate subspecies.
This area is much less heavily vegetated, and hence
drier, than the other major sampling area. The
dwarfing of these specimens is not exceptional under
the drier conditions.
That there is a genetic base to the differences
between the nominate race and rarotongensis is
suggested by the barrier counts in juveniles, where
young rarotongensis have only 2 palatals and young
fratercula fratercula have 3 palatals below the
periphery. Whether the larger size of the rarotongensis
shells merely represents more favorable moisture and
nutrient conditions on Rarotonga compared with the
offshore atolls and other Cook Islands, or is the result
of more complex factors is unknown.
There were no unusual anatomical features in the
material dissected.
Description of soft parts. — Foot and tail slender, length about
equal to shell diameter, tapering slightly then rounded posteriorly,
truncated anteriorly with head projecting slightly in front of foot.
Pedal grooves relatively low on sides of foot, suprapedal slightly
weaker than pedal, both uniting across tail. No caudal horn, caudal
foss or middorsal groove. Slime network weakly rectangular, rather
inconspicuous.
Body color in preservative light yellow-white, eyespot small and
black, rest of ommatophore with dense black speckles.
Mantle collar (MC) of average width, thin, with slight
protrusion of mantle glands onto roof. Pneumostome masked by
thickened edges of mantle collar but without distinct lobes. Anus and
pneumostome sharing common opening, relative positions as in
Endodonta fricki.
Pallial cavity (fig. 172e) extending apically for about three-
quarters whorl. Lung roof clear, without any white or black
specklings. Kidney (K) narrow, less than one-third length of pa Ilia I
cavity, abutting on loop of intestine, a significant portion reaching
hindgut. Ureter (KD) short and conspicuous, following curve of
kidney and reflexing to anterior edge of rectal kidney arm, then
opening directly onto pallial cavity. No secondary ureter present.
Hindgut (HG) paralleling parietal-palatal angle to anus, not
enlarged. Heart (H) rather large, slightly less than half length of
kidney. Principal pulmonary vein (HV) conspicuous, running along
periphery of shell from anterior end of kidney, reaching the very
slight protrusion of mantle gland onto lung roof, no conspicuous
secondary venation.
Ovotestis (G) imbedded in digestive gland just above stomach-
intestine reflexion, consisting of numerous clumps of palmately
clavate alveoli, slightly iridescent basally, strung along single
collecting tubule. Ovotestis stopping well short of digestive gland
apex (fig. 172f). Hermaphroditic duct (GD) a slim, opaque, slightly
iridescent tube running along basal margin of whorl past base of
stomach, narrowing abruptly at base of albumen gland (GG). then
running into latter to join buried stalk of talon (GT). Albumen gland
white, of loose, fine-textured acinar tissue, squeezed between loops of
intestine with head of spermatheca (S) lying on outer surface. Talon
a blind duct with expanded head tapering to a slender tube,
expanded to form carrefour just before union with hermaphroditic
duct. Prostate (DG) composed of three rows of large acini opening
into a slender tube partly obscured by uterine tube. Uterus (UT) a
very thin-walled circular tube above, past midpoint of prostate
uterus broadening into a large chamber (fig. 172f), tapering to start
of free oviduct (UV). Vas deferens (VD) a continuation of tube from
prostate, passing down to penioviducal angle where it then passes up
alongside penis, but not bound to it, before entering just below apical
insertion of penial retractor (PR). Latter very long and rather thick,
arising from diaphragm at level of spermathecal head and inserting
on head of penis (P). Latter a thin-walled muscular tube extending
about 3.5 mm. long, moderately swollen medially, tapering gradually
to both ends, internally (fig. 172d) with two longitudinal, high,
glandular pilasters, one with a secondary broad extension medially.
Pilasters uniting in atrium (Y), which is quite short.
Free oviduct (UV) about one-and-one-half times as long as
prostate-uterus, slightly swollen apically, tapering to a slender tube
scarcely wider than duct of spermatheca. Spermatheca (S) with very
slender duct lightly bound to free oviduct and margin of prostate-
uterus to midpoint of latter, then passing up surface of prostate and
starting to expand just before base of albumen gland. Head of
spermatheca pressed against albumen gland surface, bulbously
expanded, shaft inserting directly onto penioviducal angle, being
tightly bound to free oviduct for last 2 mm.
Gross appearance of digestive system differing from Endodonta
only in having the esophagus larger in diameter (probably an artifact
in preservation), and less striking constrictions at the stomach-
intestine junction. Digestive gland extending to apex of soft parts,
occupying full whorl and a half above apex of ovotestis, but stopping
several whorls short of apex in gerontic individuals (see p. 95).
Free muscle system simple. Right ommatophoral retractor
passing through penioviducal angle, uniting with right rhinophoral
retractor two-thirds of way to tentacular union with tail fan.
Columellar muscle broad and elongated, extending up to midlevel of
stomach. Buccal retractor not split, joining columellar retractor at
its tip.
Penis enervated from right cerebral ganglion. Main nerve to base
of penis, with second largest branch to vas deferens in penioviducal
angle, secondary branches to free oviduct and atrium.
Jaw of narrow plates, about four times as long as wide, with
slight trace of medial fusing.
Radula with central about 13|ii long, 8/i wide, laterals 6 to 7,
endocone becoming prominent at point of transition where ectocone
starts splitting. By outer of 10 to 13 marginals, endocone and
mesocone subequal, ectocone split into three or four smaller cusps,
basal plates broadly rectangular.
(Based on BPBM 95356 and FMNH 114556, 10 adult specimens.)
Libera subcavernula (Tryon, 1887). Figure 184
a-c.
Pitys cavernula Garrett, 1872 (not Helix cavemula Hombron &
Jacquinot, 1852, which is a synonym of Libera jacquinoti
Pfeiffer), Amer. Jour. Conchol., 7, (4), pp. 226-227, pi. 19, fig. 16
— in mountain ravines of Rarotonga, Cook Islands; Pfeiffer,
1876, Monog. helic. viv., 7, p. 568.
Libera cavernula (Garrett), Garrett, 1881 (not Hombron and
Jacquinot, 1852) Jour. Acad. Nat. Sci., Philadelphia, 8, (4), p.
392.
Helix (Libera) subcavernula Tryon, 1887, Man. Conchol., (2), 3, p.
70, pi. 13, figs. 67-69 — new name for cavernula Garrett, 1872,
not Hombron and Jacquinot, 1852.
Endodonta (Libera) subcavernula (Tryon), Pilsbry, 1893, op. cit.,
(2), 9, pp. 23, 24, pi. 5, figs. 45-48.
Libera subcavernula (Tryon), Ponsonby, 1910, Proc. Malacol. Soc.
London, 9, (1), p. 38.
f
FIG. 184. a-c, Libera subcavernula (Tryon). Rarotonga, Cook Islands. BPBM 2240; d-f, Libera tumuloides (Garrett).
Rarotonga, Cook Islands. BPBM 2239. Scale lines equal 1 mm. (MM).
427
428
SOLEM: ENDODONTOID LAND SNAILS
Diagnosis. — Shell large, diameter 5.29-7.63 mm. (mean 6.29
mm.), with 51/2-7'<i+ normally coiled whorls. Apex and spire strongly
elevated, rounded above, last whorl not descending more rapidly.
H/D ratio 0.548-0.711 (mean 0.618). Umbilicus secondarily narrowed
to form brood chamber by gradual inward protrusion of baso-
columellar margin for last two whorls, resulting opening circular or
subcircular, contained 3.58-8.09 times (mean 5.68) in the diameter.
Postnuclear sculpture of relatively low, rounded, protractively
sinuated radial ribs, whose interstices are about twice their width.
and which become reduced to irregularity on body whorl and are
absent from base of shell in adults. Microsculpture of fine, rather
widely spaced radial riblets, three to five between each pair of major
ribs, crossed by exceedingly fine and crowded spiral riblets that are
visible only under 96 X magnification. Sutures shallow, whorls evenly
rounded down to relatively shallow supraperipheral sulcus. periphery
a moderately protruded threadlike keel with weak supraperipheral
sulcus, lower palatal and basal margins rather strongly and evenly
rounded down to very slight sulcus before sharply angled baso-
columellar margin. Aperture subquadrangular. more strongly
rounded above than below protruded periphery, inclined about 25°
from shell axis. Parietal barriers 2, rarely (2.3 per cent) with lower
absent, extending posteriorly to line of vision: upper high and blade-
like, distinctly more elevated and expanded above on posterior third,
with very gradual descension until just before anterior termination;
2nd recessed to about midpoint of upper, lower but more broadly
expanded above posteriorly with rather sharp anterior descension to
normal termination, often with a weak, threadlike anterior
extension to point opposite end of upper parietal. Columellar wall
with a low to moderately elevated, broadly rounded, very deeply
recessed barrier that merges into top of columellar callus. Palatal
barriers 2, rarely (4.7 per cent) with a 3rd present, moderately deeply
recessed, extending posteriorly about three-sixteenths of a whorl:
lower at lower palatal-basal margin, flattened and weakly expanded
above on posterior third, with gradual anterior descension; 2nd
slightly less elevated, flattened above on posterior half, with slightly
sharper anterior descension; 3rd, when present, a low lamellar blade,
very short, situated between columellar and 1st palatal.
Libera subcavernula differs from Libera frater-
cula rarotongensis primarily in degree rather than in
kind. The latter has the regular sculpture much
stronger and more regularly spaced, the peripheral keel
is much more strongly protruded, the sulci are deeper,
and apparently is restricted to lowland habitats near
the ocean. L. subcavernula was an inland species with
much less prominent radial ribbing and smaller
peripheral keel. L. tumuloides has lost the radial
ribbing, generally has only a single palatal barrier and
always has only a single parietal.
Description. — Shell large, with slightly less than 6'/2 normally
coiled whorls. Apex and spire strongly elevated, form dome shaped,
last whorl not deflected, H/D ratio 0.607. Apical whorls 1%,
sculpture of fine, moderately widely spaced radial riblets, whose
interstices are 3-5 times their width, with a microreticulated
sculpture of radial and spiral riblets. Postnuclear whorls with low,
rounded, rather widely spaced radial ribs, whose interstices are 2-3
times their width, and which denticulate the sutures, becoming
obsolete on last half of body whorl. Microsculpture of fine radial
riblets crossed by much finer and more crowded spiral riblets.
Sutures margined by a protruding threadlike keel, denticulated by
radial ribs on early whorls. Whorls flatly rounded above threadlike
keel, with a distinct supraperipheral groove, evenly rounded on
elongated basal margin. Color yellowish-horn with numerous,
somewhat irregular, reddish flammulations that fade out near
umbilicus. Umbilical region strongly constricted by growth of last
whorl-and-one-half. opening almost circular, contained 4.86 times in
the diameter. Aperture subcrescentic with protruding peripheral keel
and evenly rounded margins, inclined about 20° from shell axis.
Parietal barriers 2. extending more than one-quarter whorl: upper
parietal with anterior half a low, raised lamellar ridge becoming high
and bladelike on posterior half; lower parietal similar posteriorly but
with anterior half low and threadlike. Columellar wall with a heavy
callus, surmounted by a deeply recessed, broad, lamellar barrier.
Palatal wall with two subperipheral barriers, deeply recessed,
extending three-sixteenths of a whorl: lower palatal high and
bladelike, with gradual anterior descension; upper palatal lower with
more gradual anterior descension and slightly more deeply recessed.
Height of lectotype 4.05 mm., diameter 6.67 mm.
Lectotype. — Cook Islands: Rarotonga. Collected
by Andrew Garrett. ANSP 47813.
Range. — Mountain ravines of Rarotonga, Cook
Islands (Garrett, 1881, p. 392).
Paratypes. - BPBM 2240, ANSP 290112.
Material. — Cook Islands (21 specimens, BPBM
189937, FMNH 90609, FMNH 91884, FMNH 99849):
Rarotonga (52 specimens, BPBM 2240, BPBM 167429,
FMNH 73892, ANSP 47813-4, AMS, AMS C18488,
ANSP 290112, USNM 77110, USNM 98745, USNM
203454).
Remarks. -- Although Garrett (1881, p. 392)
implied that this species was widely dispersed and
"Found plentifully in the mountain ravines," no
specimens were collected in 1964 and 1965. Apparently
it was an inland replacement of Libera fratercula
rarotongensis. L. subcavernula almost certainly was
derived by reduction of the keel and ribbing. No
intermediate examples were seen. The lectotype is a
rather flat and heavily sculptured specimen, but is the
best preserved example in the type set.
Many small samples in older museum collections
(table CVI) were seen. Variation was only in size,
reflecting retention of large specimens by Garrett
(BPBM 2240) and the presence of small individuals in
the Hedley (AMS) and Fulton (RSM) collections.
There is no indication of variation between popu-
lations as in Thaumatodon multilamellata.
Libera tumuloides (Garrett, 1872). Figure 184d-f.
Pitys tumuloides Garrett, 1872, Amer. Jour. Conchol., 7, (4), pp.
225-226, pi. 19, fig. 15 — high up in a mountain ravine on
Rarotonga, Cook Islands.
Endodonta tumuloides (Garrett), Binney, 1875, Proc. Acad. Nat.
Sci., Philadelphia, 1875, p. 248, pi. 21, fig. 6 (radula).
Helix tumuloides (Garrett), Pfeiffer, 1876, Monog. helic. viv., 7, p.
567.
Libera tumuloides (Garrett), Garrett, 1881, Jour. Acad. Nat. Sci.,
Philadelphia, 8, (4), p. 393; Ponsonby, 1910, Proc. Malacol. Soc.
London, 9, (1), pp. 40-41.
Helix (Libera) tumuloides (Garrett), Tryon, 1887, Man. Conchol.,
(2), 3, p. 70, pi. 13, figs. 70-71.
Endodonta (Libera) tumuloides (Garrett), Pilsbry, 1893, op. cit.,
(2), 9, pp. 23-24, pi. 9, fig. 26 (radula).
Diagnosis. — Shell large, diameter 6.18-7.17 mm. (mean 6.51
mm.), with 6'/8-7''2 normally coiled whorls. Apex and spire rather
strongly elevated, broadly rounded above, last whorl normally
slightly to moderately deflected below periphery of penultimate
whorl, H/D ratio 0.553-0.812 (mean 0.671). Umbilicus secondarily
narrowed to form brood chamber by gradual inward growth of baso-
columellar margin over last two whorls, inward growth accelerating
in later stages, resulting opening somewhat irregular, contained 3.62-
M
EH
g
<
;
§
I
I
3
S
I
•
H
5
cn"
CD
o
oo
rH
CO
8
c-
•£
CD'
oo"
c-
C-'
CD*
co
3
CO
in
i
c-
m
CD
1
00
in
1
CM
CO
o
5
1
m i
Cn rH
CO
c-
CO
in
m
CM
o
CO
OO
CM cn
^.^
c
^
o
CO
o
•^
0
in
o
^f1'
O ^"
Q
-H
^-^
-H
x_x
-U
*^*
-ft
^^-
HH
**^s
-ft •— '
in
Tj*
in
cn
C-
m
CD
cn
oo
CD
in"
in
in"
in"
m'
in
^
co"
oo"
M
r- <
4
CM"
oo
CO
-t
m
CM
•51
i
CM
f v
rH
£
rH
CO
CD
O
1
X
CD
CD
CD
CD
CO
CO
CO
c-
CD
c-
CD
CD
CD
iH
in
m
CO
~
C-"
oo"
So"
i-t
co"
LO
c-
00
CD
rH
cn
CD
CD
CD
CO
c-
CO
O
O
O
o
o
0
CD
i
1
CD
1
O
1
00
1
CO 1
-—
C-
pi
CM
CO
CD
cn
o
o
CD
^ cn
c2
o
o
O
CD
rH
O
s
TH
O
S
tH
O
CD
in
CM
O
tr-
iO
o m
Q
o
O
O
o
O
o
O
o
O
c
o o
-H
-H
-H
-H
-H
-H — '
X
3
O
TH
cn
TH
CM
O
CO
CM
CD
CD
CD
CD
CD
CD
O
0
o"
0
o"
O
c?
S"
oo
0"
00
So"
m
o*
oo
CD"
o
CD'
CD'
CD"
IT-'
CD'
c-'
S
CO
CM
<N
cn
CM
cn
O
CO
i
m
CD
rH
1
CD
CO
TH
iH
CO 1
CD C-
U
rH
CD
rH
rH
t-
<N
in
tH
O
0 CD
O
in
O
in
O
m
O
m
O
CD
0 CO
nj
-H
^^
-H
*— ••
-H
v_*
•^^
-^
•*~s
HH s —
S
CO
cn
in
o
CD
rH
CM
5
CO
cn
in
CD"
CD
CD'
co"
CD'
g-
5T
TH
_.
^
^.
CM
CO
cn
in
CO
•
CO
"*"
•*'
^'
^r
•*"
4_(
i
CO
1
i
cn
i
CD 1
J2
CO
CO
CM
C-
TH
CD
••*
co
co
cn
cn CD
_bp
o
m
rH
O
rH
rH
CO
rH
in
tH CO
U
o
CO
O
CO
O
CO
0
co
O
co
0 CO
-H
-H
-H
-H
-H
O
O
iH
cn
CM
in
c-
C-
OO
cn
cn
CO
co'
co
co"
co"
co"
TC
0
0
m
m
CO
iH
CO
3!
00
c
00
co"
CM
CD
CO
IH
CM
in"
i
CD
tH
rH
CO
rH
CD'
1
CO
CM
c
m
CO
to
1
•*
E-
c
co
O
2L-
G
2!.
o
CO
CO
00
CO
cn
05
O
<N
•*'
•*'
in
m
cT
co"
5~
??
1
^*<
TH
+
*^
tH
^*.
"^.
rH
co
CO
C-
1
CO
CO
C-
CM
c-
r
i
c-
E-
(N
rH
iH
m
rH
CO
CO
CD
CO
6?
TH
00
in"
co
c-
co"
t-
c-
CO
E-
c
1
(N
O
o"
1
c
c-
rH
o'
1
o
co
CD
o
1
CO
0
O
CD
O
O
CO
c
o
G
0
G
G
G
c
0
IT-
CO
CM
O
C-
CD
OO
CD
C-
CD
CD
o"
O
c"
o'
CD"
CO
in
co"
IT-
cT
T-t
CO
CO
c
co"
1
rH
O
in
o
CD"
i
tH
cn
G
CD'
1
TH
TH
00
o
C-"
1
00
o
4!
CO
CO
o
4t
CO
G
CD
CO
0
-H
c-
CD
CO
CD"
co"
CD"
CD'
O
tH
r-
cn
!TJ
e-
c-
rH
in"
i
CO
m
CO
c-
o
•*'
in
CM
00
CO
G
1
in
<N
TH
1
0
c
-H
(N
co
0
-H
CM
in
S
o
4t
CO
s
O
4t
m
s
c- i
CO CO
cn tr-
oo °°
To c-
•=- 7
c-
t-
m
6?
oo
CO*
(N i
O CO
co cn
G co"
co
o
CM CO
C- I
. co
in m
4t ' —
6?
00
CM i
CM m
CD C-
cn
co
(N 00
'rH' C-
c- >T-
c-
00
in
c- in
(N Tjl
in
co
00
in i
rH CM
CM OO
O C-
•H ^
in
co
cn"
00 <»
m
c-
; in
1 00
O 1
^t o
iH G
G m
CM I
in CM
IH CM
G m
' G
1
1
G G
in
CO
in
G 0
HH •*-
in
CO
in
S
05
in i
o cn
rH CO
o" oo"
in
C- 1
co cn
CO C-
CO i
00 CD
rH 00
m
CM 1
CD 00
rH in
O CO
O CO
0 Tj<
4H *•— '
S
-ft ^"^
c-
-H **~*
m
o
S
S
co
m
m
8.
in
oo
•
. CM
. 00
c-
cn tH
oo
CD
(N
rH
TH
CO iH
rH rH O
m cn
rH O
.CM
O5 T*i
Set
n)
|
rH
*
TH
£
CO
c-
00
c-
OO O ^t
C- O5 CM ,.
•^i CM OJ
.C J=
CO 0
f- O5
^< CM
CO C-
(N CD
CM tH
•g
C- O5
CD 00
TH rH
i
Ml
w
rH
O,
CO
Z
OH
in
0. OH ^ 2
U O
1 1
O. OH
co co
OH OH
's
22 (A
ca m 5
O. OH ™
VI
--H
t-t
0)
0
<
c2
<
<^
<tj <tj CO
M M
<3 <!
m co
cr
CQ CO <
OH
1
3
u
429
430
SOLEM: ENDODONTOID LAND SNAILS
6.93 times (mean 5.08) in the diameter. Early postnuclear whorls
with narrow, strongly protractive major radial ribs, that are absent
from last few whorls and very reduced and irregular on early spire.
Microsculpture of fine radial riblets, broader and more widely spaced
below than on upper spire, crossed by extremely fine and crowded
spiral riblets that are barely visible under 96 X magnification.
Sutures very shallow, whorls flatly rounded down to prominent
supraperipheral sulcus, periphery a narrow, rather sharply protruded
threadlike keel with weaker subperipheral sulcus, lower palatal and
basal margin evenly and rather broadly rounded down to distinct
sulcus before protruded baso-columellar margin. Aperture subquad-
rangular, rounded above and below strongly protruded periphery,
inclined about 30° from shell axis. Parietal wall with single barrier,
extending posteriorly to or beyond line of vision, high and slightly
more expanded above on visible posterior quarter, with gradual
anterior descension to midpoint, anterior half a raised threadlike
ridge. Columellar wall normally (71.8 per cent) without, often (28.2
per cent) with a low and broadly rounded, very deeply recessed
barrier, visible only by extreme tilting of aperture. Palatal wall
normally with a single subperipheral, medially located, moderately
deeply recessed barrier, extending posteriorly three-sixteenths of a
whorl, occasionally (5.2 per cent) with a second, slightly lower,
barrier: major barrier high and slender, flattened above on posterior
half, with gradual anterior descension; 2nd, when present, located
nearer columellar margin, slightly reduced in height.
The complete loss of major radial ribbing on the
lower spire and body whorl combine with presence of
only 1 parietal and 1 palatal to immediately separate
Libera tumuloides from the other Rarotongan species.
Society Islands species with reduced radial sculpture,
such as L. heynemanni and L. garrettiana, differ
immediately in the greater number of apertural
barriers.
Description. — Shell relatively large, with slightly less than 7Vi
tightly coiled whorls. Apex strongly elevated, whorls descending
rapidly, form dome shaped, body whorl slightly deflected, H/D ratio
0.686. Apical whorls l'/2, sculpture eroded except for traces of radial
ribbing in the sutures. Postnuclear whorls with low, rounded, rather
widely spaced radial ribs that weakly denticulate the suture on the
upper whorls, becoming obsolete on the lower spire and body whorl.
Microsculpture of very fine radial riblets, crossed by much finer and
more crowded spiral riblets. Sutures shallow, margined by protruded
threadlike keel. Whorls flatly rounded above periphery and partly
flattened on basal margins. Color light yellow horn, with broad,
irregular, light- to dark-toned, reddish flammulations. Umbilicus
strongly constricted to form brood chamber by last whorl-and-a-half,
opening subcircular, contained 5.10 times in the diameter. Aperture
subquadrangular with flattened upper palatal margin and elongated,
gently rounded basal margin, inclined about 25° from shell axis.
Parietal wall with single long barrier, low and threadlike anteriorly,
becoming high and bladelike posteriorly, running beyond line of
vision. Columella with a heavy, white callus on which a broad,
deeply recessed radial swelling occurs. Lower palatal lip with a
single, medial, deeply recessed, bladelike barrier, extending slightly
more than one-eighth whorl, recessed almost one-eighth whorl within
aperture. Height of lectotype 4.57 mm., diameter 6.67 mm.
Lectotype. — Cook Islands: Rarotonga, high up in
a mountain ravine. Collected by Andrew Garrett.
ANSP 47815.
Range. — A small area of about one-half acre
located nearly 2 miles inland, Rarotonga, Cook Islands
(Garrett, 1881, p. 393).
Paratypes. - BPBM 2239, ANSP 290098.
Material. — Cook Islands (11 specimens, USNM
77940, USNM 98742, FMNH 91146, FMNH 91841):
Rarotonga (61 specimens, BPBM 2239, BPBM 167427,
FMNH 73891, FMNH 117279, ANSP 47815, ANSP
290098, AMS, Zurich, USNM 77037, USNM 203452).
Remarks. — Of an original "over 300 specimens,"
only 72 were located in museum collections. There was
little variation in size and shape (table CVI). The
highly restricted range of "one-half an acre" would be
difficult to find even if a valley name had been
furnished. Probably at least 3,400 acres of Rarotonga
would lie "nearly two miles inland" by foot (or more).
Providing the species is not extinct, much more
thorough collecting will be required than was possible
in 1964 and 1965 to locate the colony. Since no
material of L. subcavernula was found, I suspect both
may be extinct.
L. tumuloides has lost the major radial ribbing
and retains only 1 parietal and 1 palatal barrier. It
shows intensification of the trends seen in L. subcaver-
nula when compared with L. fratercula, and probably
was directly derived from this stock.
I could not locate the radular material figured by
Binney (1875) and Pilsbry (1893-1895). Their drawings
show no peculiarities that would separate them from
species studied during preparation of this report.
Libera sp.
Helix excavata Hombron & Jacquinot, 1841 (not Bean, 1830), Ann.
Sci. Nat., Zool., (2), 16, p. 64 — Tahiti; Hombron and Jacquinot,
1852, Voy. Pol. Sud, Astrolabe et Zelee, Atlas, pi. 6, figs. 9-12 -
Tahiti, Society Islands; Rousseau, 1854, op. cit., 5, pp. 17-18;
Ponsonby, 1910, Proc. Malacol. Soc. London, 9, (1), p. 43.
Helix (Libera) jacquinoti Tryon, 1887 (not Pfeiffer, 1850), Man.
Conchol., (2), 3, pi. 13, figs. 72-74.
Range. — Unknown.
Material. - "Tahiti" (3 specimens, BPBM 167408,
ex Fulton). No locality (10 specimens, BPBM 8599,
BPBM 8690 ex Garrett, FMNH 117007).
Remarks. — Ponsonby (loc. cit.) and Cooke
(manuscript notes) considered that Helix excavata of
Hombron and Jacquinot was a variety of Libera
heynemanni. I disagree, since the type figures clearly
show radial ribbing on the upper shell surface (but
absent below periphery) while heynemanni lacks all
ribbing. The figures show a very tiny umbilicus and 2
strong parietal barriers, the lower deeply recessed, but
no palatals. Lack of the latter in the illustration has
no significance, since they are absent in the other
Libera on the same plate. Rousseau's (loc. cit.)
description was based only on the figures and is
worthless in determining its identity. The specimens
cited above, ranging from 5.30 - 6.15 mm. in diameter,
agree fairly well with the figures, although slightly
smaller than the 7 mm. size cited by Rousseau. They
are slightly larger and higher than most L. dubiosa,
but may be only extreme variants of that species.
Until localized material agreeing with the type
figures is rediscovered, there is no reason to rename
the pre-occupied Helix excavata Hombron & Jac-
SYSTEMATIC REVIEW
431
quinot. I prefer to leave it as a dubious species.
Ponsonby (1910, p. 43) indicated that the type
specimens are not in the Paris Museum and I could
not locate any specimens during my visits to that
institution.
Libera sp.
Helix bursatella var. alpha, Gould, 1846, Proc. Boston Soc. Nat.
Hist., 2. p. 175 — Tahiti and Eimeo (Moorea). Society Islands:
Pfeiffer, 1848, Monog. helic. viv., 1, p. 185; Gould, 1852, U. S.
Explor. Exped., Wilkes, 12, p. 52.
Material. — Location unknown (2 specimens,
BPBM 189935).
Remarks. — The large, nearly smooth shell closely
matches Gould's description of variety alpha. It
appears to be a large form or close relative of
heynemanni, but without new material from a precise
locality, no nomenclatural recognition is warranted.
The largest shell is 8.17 mm. in diameter with 8'/2
whorls, H/D ratio 0<640.
Libera sp.
Libera n. sp.. Garrett, 1881. Jour. Acad. Nat. Sci.. Philadelphia, 8,
(4), p. 393 — lowland forest at Aitutaki, Cook Islands.
Remarks. — Garrett (loc. cit.) reported that five
shells of this, "the smallest species in the genus," were
deposited in the Museum Godeffroy, Hamburg. These
collections were destroyed during World War II. No
collecting has been done on Aitutaki since Garrett's
time.
Genus Gambiodonta, new genus
Extremely large Endodontidae in which the umbilicus is
modified to form a brood chamber by inward growth of the last
whorl. Apical sculpture consisting of very broad and rounded major
ribs interspersed with finer riblets. Postnuclear sculpture of narrow
to broadly rounded, strongly protractive radial ribs that denticulate
the slight to very strong peripheral keel and may be reduced or
absent on base of shell. Strong secondary spiral cording usually
present. Whorl count generally more than 6 (except in G. mirabilis),
spire strongly elevated, dome shaped above. Parietal barriers extend-
ing more than one-quarter whorl, 2-5 major barriers (usually 4-5)
and five to eight accessory traces (except in G. grandis). One
columellar barrier usually with a single accessory trace. Major
palatal barriers 4, lower almost reduced to size of accessory traces
(not differentiated in G. mirabilis and G. grandis), with three to
twelve accessory traces. Anatomy unknown.
Type species. — Gambiodonta pilsbryi pilsbryi,
new species.
Both Libera and Pseudolibera, the other two
Polynesian genera with an umbilical brood chamber,
have a greatly reduced number of apertural barriers,
different apical sculpture (fig. 22a-c), and quite
different postnuclear sculpture. Formation of an
umbilical brood chamber has produced many sim-
ilarities in form and general appearance, but the
patterns of sculpture, apertural barriers and rate of
umbilical closure are completely different in Libera,
Pseudolibera, and Gambiodonta.
The apertural barriers in Gambiodonta are essen-
tially identical to those of Anceyodonta, differing only
in minor details such as having the lower palatal much
more reduced in size (accentuating a trend present in
many Anceyodonta) and an increased number of
accessory traces (probably reflecting the greater area
of the parietal and palatal walls, hence more room for
accessory traces). The reduction of elevated parietals
to 2 or 3 (G. mirabilis and G. agakauitaiana) reflects
secondary shell modifications and small size, respec-
tively, while the development of 5 relatively low
parietals in G. pilsbryi correlates with depressed shape
and strongly protruded keel of that species. Placement
of the accessory traces, with two or three above the
upper palatal and parietal barriers, with one or two
between each pair of major barriers, follows the exact
pattern seen in those Anceyodonta with accessory
traces present.
Sculptural similarities of Anceyodonta and Gam-
biodonta are marked. The secondary spiral cording
present in many Anceyodonta is very strongly devel-
oped in most Gambiodonta, being absent only in the
highly modified G. mirabilis and G. grandis. Three
Gambiodonta, G. mirabilis, G. mangarevana, and G.
agakauitaiana, have the same narrow ribbing found in
Anceyodonta', the other three species, G. pilsbryi, G.
tumida, and G. grandis, have developed quite broadly
rounded ribs. Most species have a basically identical
color pattern, except for G. mirabilis. It is noteworthy
that the larger species have modified ribbing, the
smaller typical endodontid ribs. Gambiodonta differs
most obviously in sculpture by its very large major
apical ribs (fig. 22a-c).
Comparisons of form are negated by the vastly
different umbilical structures. In Anceyodonta the
umbilicus generally is minute or constricted internally
with the last whorl decoiling to form a wider opening
(A. labiosa, A. subconica, A. soror, and A. difficilis)
and only in A. andersoni and A. alternata (fig. 82c, f)
is the umbilicus broadly open internally. In Gambio-
donta the juvenile umbilicus is very broadly open (fig.
189d) with a sharp marginal angulation developed
after about 3'/2-5'/2 whorls. In G. pilsbryi aukenensis,
for example, within slightly more than one-half whorl
after this, the angulation has become a weak keel.
Very suddenly, an extremely sharp inward projection
of this keel starts from the baso-columellar margin
(fig. 185). The inward growth continues for about one-
quarter to one-third whorl, and at the end, the
columellar wall has been grossly elongated, slanted
downward and inward, obscuring approximately one-
third of the umbilical width. Inward growth stabilizes
at this point, with the subsequent half whorl of
umbilical margin growth irregularly maintaining the
same distance from the columellar margin of the
preceeding whorl. This is particularly obvious in
Figures 186b; 187b, e; and 188b. When this inward
growth of the baso-columellar margin stabilizes, the
basal wall remains roughly parallel to the plane of
coiling, while the inner columellar wall slants diag-
onally toward the shell axis (from top to bottom). The
432
SOLEM: ENDODONTOID LAND SNAILS
FIG. 185. Form of umbilical closure in Gambiodonta pilsbryi
aukenensis. Aukena, Mangareva, Gambier Islands. BPBM 138711.
(MM).
inclination of the aperture is such that a distinct
"leading edge" of columellar wall growth is visible in
each bottom view. In all intact adult specimens
examined, this "leading edge" stops either at or just
short of the point at which the sudden inward
projection of the baso-columellar margin started.
Hence closure of the umbilical brood chamber in
Gambiodonta is completed within one whorl of
growth. Effective narrowing of the umbilicus takes less
than one-third whorl, and, with only very minor
deviations, growth ceases one whorl after umbilical
closure begins. The same pattern is repeated in the
other species of Gambiodonta, the starting point of
inward whorl growth varying from the 4th to 7th
whorl, depending on the whorl count of the individual
adult shell.
All Gambiodonta collected by the Mangarevan
Expedition were taken from cave deposits, washed
loose from road-cut and open-ground deposits, or
taken from semi-consolidated sand deposits. As a
result, the umbilici and apertures of all specimens were
tightly clogged with dirt and/or small pebbles. Time
did not permit more than a partial sampling of
specimens for cleaning, since removal of sufficient
apertural debris to establish the number of elevated
parietals and cleaning enough of the umbilicus to
check for apical encroachment by the embryos took up
to 20 min. per specimen. Where material permitted, at
least five specimens of each form (in addition to those
previously cleaned by the Bishop Museum staff) were
cleaned sufficiently to check parietal elevation and
establish palatal trace counts. Since only a small
percentage of the available material was checked for
the trace counts, these figures in Table CVII cannot
be considered statistical, but only reflect the observed
range of variation. More specimens were checked for
parietal elevation than trace counts, and no variation
in number was observed.
Specimens which had the umbilicus completely
cleaned showed no indication of apical encroachment
and embryos were found only in two specimens of
Gambiodonta tumida.
Variational trends within the genus are
comparatively simple. As mentioned above, three
species — G. grandis, G. mirabilis, and G. tumida —
have the radial ribs greatly widened, rounded, and
markedly reduced or absent on the shell base, while
the other three retain the typical ribbing seen in
Anceyodonta. The characteristic secondary spiral
cording is very well developed in all species but G.
mirabilis and G. grandis. Peripheral keel protrusion is
weakest in G. mangarevana, only slightly more
strongly developed in G. tumida, very strongly devel-
oped in G. pilsbryi aukenensis and G. grandis, with G.
mirabilis having two additional keels developed. There
is thus no correlation between changes in ribbing,
secondary sculpture, and the development of the
peripheral keel. The size range (table CVII) is strongly
skewed by the presence of G. grandis. From the
smallest, G. agakauitaiana, to the second largest, G.
tumida, there is a percentage size increase of 8.5-20.9
per cent from species to species and a total increase in
mean diameter of only 65.7 per cent from the smallest
to largest. The difference in mean diameter between G.
tumida and G. grandis is 98.4 per cent. The gigantic
size of G. grandis is only partly accounted for by an
increase in whorl count (from a mean of 6%+ to 73/s),
with the rest of the difference resulting from whorl
enlargement. First whorl diameter is 0.64-0.69 mm. in
G. pilsbryi and G. agakauitaiana; 0.76-0.82 in G.
mirabilis and G. tumida; and 1.05-1.15 mm. in G.
grandis.
Distribution patterns are relatively simple. Man-
gareva Islet has four species — G. mangarevana, G.
pilsbryi pilsbryi, G. tumida, and G. mirabilis; Aukena
Islet has three species — G. pilsbryi aukenensis, G.
grandis, and G. mirabilis; and Agakauitai has two
species — G. agakauitaiana and G. grandis. Two
species, G. grandis and G. mirabilis, were collected on
two islets without subspecific differentiation, while G.
pilsbryi is represented by different subspecies on two
islets. No Gambiodonta were collected on Akamaru or
any of the smaller islets. Indeed, all known material of
the genus was collected by the B. P. Bishop Museum
Mangarevan Expedition between May 23 and June 11,
1934 except for a single shell (BMNH 1886.6.9.919)
without exact locality data received by the British
Museum (Natural History) from J. L. Lambert. The
lip is badly broken and the shell is 4.78 mm. in
diameter, H/D ratio 0.836, with 7% whorls. The
sculpture is very much like that of G. pilsbryi, but the
shell is much more elevated than any other Gambio-
donta examined. It very probably represents an
unnamed species, but is not described since it is
without adequate locality data.
The derivation of Gambiodonta from the same
stock that produced Anceyodonta would be logical,
CO
4
oo
CO
to
I
«?
CO
U --H
I
o
Q
O
M
pq
o
M
a
o
43
o
I
Q
^
co
1
to
CO
CO
CO
10
tr-
co
c-
i
oo
.
CO
to
in
o
oo
10
oo
^
1O
to
I
to
I
CO
To-
to
o
of
U3
10
CO
^
1O
IO
to
to
oo
to
IO
1
IO
oo
-^
CO
1O
(N
1O
10
CO
+
00
00
IO
tr-
to
•
o
o
c-
(N
c-
02
o
10
IO
o
M
ffi
fc
o
<«
s
10
o
CO
CO"
c-
en
<N
oo
"*'
CO
IO*
CD
•*'
10
•*"
oo
CO
CO
o
10
vo"
00
10'
oo
o>
o
CD
(N
1-1
CQ
<
EH
DO
X
CO
CO
CM
I
o
to
<N"
IO
CO
o
CO*
rH
CD
(N
OO
<N
00
oo
c-
o
to
oo
CO
&
CO
C-
•*'
o
CO
CO
•**
CO
(M
c-
10
(N
10
c-
IO
CO
O3
CO
oo
CO
CO
CD
CO
1O
o
to
IO
CO
CO
IT-
CD
IO
EO C
_ u a
3 CX X
Z co w
CO
CO
02
c-
co
CO
OS
IO
1M
Z
JD
"Sn
5
in
s
•&
•3
M
•H
"g
a
2
6
S
S:
433
434
SOLEM: ENDODONTOID LAND SNAILS
except for the vast difference in umbilical contour
between the Minidonta simulata group and the
juvenile Gambiodonta. I think it more probable that
Gambiodonta diverged after the Anceyodonta evolu-
tionary level had been obtained. A series of mutations
from such a start as could be represented by the A.
andersoni and A. alternata pair (fig. 82c-f) provides a
clear indication of how the transition could have
occurred. While the smallest Gambiodonta, G.
agakauitaiana, barely falls within the size range of
Anceyodonta, its strongly developed peripheral keel,
secondarily reduced number of elevated parietals, and
quite high spire suggest that this is a comparatively
specialized species, rather than being near a general-
ized ancestral state. Although the type of G. mangare-
vana presents the most generalized appearance found
in known Gambiodonta, even this species seems too far
removed from the pattern of Anceyodonta to be
considered a linking or intermediate form. The gap
between Anceyodonta and Gambiodonta is fully
equivalent to the gap seen between Mautodontha and
Libera.
No phylogenetic ordering of species within Gam-
biodonta seems possible, except to note that G.
mirabilis and G. grandis are highly specialized, while
the others show combinations of generalized and
specialized features. More information could be ex-
pected after stratigraphically oriented collections have
been made on the Mangareva islets. On Mangareva
Islet, for example, material from Stations 142 and 277,
which are within a few hundred feet of each other at
most, differ markedly in species abundance:
Station
142
277
7
26
23
28
62
1
Species
G. mirabilis
G. p. pilsbryi
G. tumida
The collections were made at different times and by
different people - Station 142 on June 3, 1934, by C.
M. Cooke and Yoshio Kondo; Station 277 on June 26,
1934, by Donald Anderson — so that the possibility of
personal bias in collection must be considered. Since
similar discordant numbers were found in Anceyodonta,
where the small size range would negate any sampling
bias under field conditions, I have no doubt that the
differences between thanatocoenoeses are real. The
Mangarevan Expedition collectors were primarily
interested in live material, and sampling of the fossil
deposits was not done with any idea of studying time
distribution of the material. While Cooke (1935, p. 42)
concluded that "These fossil beds are not of any
considerable age but represent lowland fauna that
probably existed after the arrival of the Polynesians,"
the different species content between stations and
obviously great difference in preservation seen among
available material, combine to suggest that quan-
titative stratigraphic sampling of the Aukena, Man-
gareva, and Akamaru beds might provide sequential
data. Obviously, fossils are present in sufficient
quantity to allow use of radiometric dating methods,
so that possible changes in species abundance and,
potentially, information concerning their time of
appearance might be gained. Unfortunately, the extent
and depth of these beds are unknown, so that
preliminary exploration would be required before the
advisability of intensive study could be determined.
These are the only known major Polynesian deposits
of endodontid shells. In view of the great amount of
minor evolution that took place on Mangareva, further
study of these is greatly needed.
KEY TO THE GENUS Gambiodonta
1. Body whorl with periphery keeled or protruded, but no other
keels present 2
Body whorl with three prominent keels (fig. 188c).
Gambiodonta mirabilis, new species
2. Diameter at 6 whorls less than 7.00 mm.; many parietal traces.
3
Diameter at 6 whorls more than 9.50 mm.; few parietal traces.
Gambiodonta grandis, new species
3. Major radial ribbing prominent on base of shell 4
Major radial ribbing absent from base of shell (fig. 188a).
Gambiodonta tumida, new species
4. More than 60 ribs on body whorl; adult diameter more than
4.25mm 5
Less than 60 ribs on body whorl; adult diameter less than 4.15
mm Gambiodonta agakauitaiana, new species
5. Major parietal barriers 5, weakly elevated posteriorly; spire
relatively low, mean H/D ratio less than 0.600 6
Major parietal barriers 4, strongly elevated posteriorly; spire
strongly elevated, mean H/D ratio more than 0.650.
Gambiodonta mangarevana, new species
6. Periphery strongly protruded (fig. 187a); mean ribs on body
whorl about 90; Mangareva Islet.
Gambiodonta pilsbryi pilsbryi, new species
Periphery less strongly protruded (fig. 187d); mean ribs on body
whorl about 78; Aukena Islet.
Gambiodonta pilsbryi aukenensis, new subspecies
Gambiodonta agakauitaiana, new species (Solem &
Cooke). Figures 22c-e; 186a-b.
Diagnosis. — Shell very small, diameter 3.91-4.05 mm. (mean
3.73 mm.), with 6-6% tightly coiled whorls. Apex and spire markedly
elevated, slightly rounded above, last whorl only slightly deflected
below periphery, H/D ratio 0.633-0.716 (mean 0.675). Umbilical
opening irregularly ovate, modified internally to form brood
chamber. Postnuclear sculpture of high, broad, sharply delineated,
strongly protractively sinuated radial ribs, 45-57 (mean 52.0) on the
body whorl, whose interstices are less than twice their width.
Microsculpture typical, five to eight microradials between each pair
of major ribs, spiral cording most strongly developed on base of shell.
Sutures shallow, whorls sloping directly to edge of deeply and
sharply outlined supraperipheral sulcus, periphery sharply and
narrowly protruded into a threadlike keel. Aperture compressedly
ovate, strongly marked internally both by protrusion of peripheral
keel and upper edge of supraperipheral sulcus, inclined about 30°
from shell axis. Major parietal barriers 3, extending well beyond line
of vision, with five to eight accessory traces: in undamaged specimen,
major parietals threadlike to beyond line of vision, when apertural
edge is broken, 3rd parietal can be seen to elevate one-quarter whorl
behind aperture; upper 2 becoming weakly elevated somewhat
posterior of this point. Accessory traces in normal position.
Columellar barrier a high lamellar blade, parallel to plane of coiling,
reaching almost to lip edge, with gradual anterior descension. Major
palatal barriers 4, extending nearly one-quarter whorl, with five or
six accessory traces: lower palatal very greatly reduced in height,
SYSTEMATIC REVIEW
435
ab
barely larger than neighboring accessory trace; 2nd and 3rd palatals
high, bladelike, deeply recessed, with very gradual anterior descen-
sion; 4th palatal supraperipheral in position, reduced in height, a V-
shaped ridge. Palatal traces in normal position.
The very small size, deep supraperipheral sulcus,
strong but narrow peripheral keel, and presence of
only 3 major parietal barriers that are very deeply
recessed within the aperture combine to separate
Gambiodonta agakauitaiana from other species of the
genus. The only species that approaches this in size,
Gambiodonta mangarevana, has only a faint in-
dication of a supraperipheral sulcus, much finer and
more crowded ribbing, and only faint indication of a
protruded peripheral keel.
Description. — Shell very small, with 6 tightly coiled whorls.
Spire dome shaped, rounded above, last whorl slightly deflected,
H/D ratio 0.706. Embryonic whorls 1!4, with very heavy protractive
radial ribs. Postnuclear whorls with high, wide, protractively
sinuated radial ribs, 54 on the body whorl, whose interstices are less
than twice their width. Microsculpture of exceedingly fine radial
riblets. much finer and more crowded spiral riblets, and a secondary
sculpture of close-set spiral cords. Spiral ribbing strongest on base
but also prominent in supraperipheral sulcus, weaker above. Sutures
shallow, whorls strongly rounded above deep, prominent suprape-
ripheral sulcus. Radial ribbing weaker in sulcus, becoming more
prominent in crossing the somewhat protruded threadlike carination,
but little reduced on base of shell. Umbilicus ovately open,
constricted below, enlarged interiorly to form brood chamber.
Aperture roughly ovate with sinuate upper margin, somewhat
flattened below, inclined about 30° from shell axis. Parietal wall with
12 barriers, the next to lowest becoming high and lamellate
posteriorly, others threadlike to past the line of vision. Columellar
barrier a high lamellate ridge, lying parallel to plane of coiling.
Major palatal barriers 4, with numerous accessory traces: 1st palatal
reduced in size, a short threadlike ridge; other 3 long, relatively low,
the upper located just above periphery of body whorl. Height of
holotype 2.76 mm., diameter 3.92 mm.
Holotype. — Gambier Islands: Mangareva, Station
195, Agakauitai Islet, northwest side. Collected on
sandy soil by Donald Anderson on June 8, 1934.
BPBM 138903.
Range. — Agakauitai Islet, Mangareva, Gambier
Islands.
Paratypes. — Same as list of material.
Material. — Mangareva: Agakauitai (Station 195)
on northwest side (17 specimens, BPBM 138903).
Remarks. - The six adult specimens showed
comparatively little variation in size, shape or apertur-
al barriers. Gambiodonta agakauitaiana is remarkable
for the reduced size of the palatal barriers and the
very deep recession of the lamellate parietals. The
reduction to 3 parietals probably is correlated with the
very small size.
All specimens were taken at the single station,
where G. grandis was twice as numerous.
FIG. 186. a-b, Gambiodonta agakauitaiana, new species. Station
195, Agakauitai Islet, Mangareva, Gambier Islands. Holotype.
BPBM 138903; c. Gambiodonta mangarevana, new species. Station
189, Mangareva Islet, Mangareva, Gambier Islands. Holotype.
BPBM 141695. Scale lines equal 1 mm. Drawings by YK reproduced
through the courtesy of Bernice P. Bishop Museum.
436
SOLEM: ENDODONTOID LAND SNAILS
Gambiodonta pilsbryi pilsbryi, new species and
subspecies (Cooke & Solem). Figure 187a-c.
Diagnosis. - Shell of average size, diameter 4.58-5.29 mm. (mean
4.89 mm.), with 6'/6-7'/6 normally coiled whorls. Apex and spire
moderately elevated, weakly flattened above, last whorl slightly
deflected below periphery, H/D ratio 0.514-0.652 (mean 0.582).
Umbilical opening irregularly oval, internally modified to form brood
chamber. Postnuclear sculpture of narrow, prominent, strongly
protractively sinuated, rather crowded radial ribs, 74-99 (mean 89.6)
on the body whorl, whose interstices are 2-3 times their width.
Microsculpture of fine radial and finer spiral microriblets, four to
seven between each pair of major ribs, with a secondary sculpture of
prominent spiral cording, especially noticeable on base of shell.
Sutures shallow, whorls strongly rounded to prominent suprape-
ripheral sulcus, periphery protruded into a threadlike keel. Aperture
flatly ovate, internally showing protrusion of periphery, inclined
about 25° from shell axis. Parietal barriers 5, extending posteriorly
beyond line of vision, with seven to eight accessory traces: major
parietals threadlike for first quarter whorl, weakly and almost evenly
expanded posteriorly at edge of vision. Accessory traces very slender,
anteriorly indistinguishable from major barriers. Columellar wall
with single, high, bladelike barrier, parallel to plane of coiling,
reaching anterior margin, usually with one or two very small
accessory traces. Palatal barriers 4, deeply recessed, extending about
three-sixteenths of a whorl, with six to eight accessory traces: lower
palatal a greatly reduced ridge; 2nd and 3rd high lamellar blades,
with gradual anterior descension; 4th palatal supraperipheral,
reduced in height, a V-shaped ridge lying opposite expanded portion
of upper parietal. Palatal traces as in G. pilsbryi aukenensis.
The average size, relatively flattened shell, 5
major parietals, protruding carina, and fine ribs are
diagnostic and prevent confusion of G. pilsbryi with
any other Gambiodonta. The large G. mirabilis has
the three keels, while the smaller G. mangareuana has
only 4 parietals and is much, much higher. The
subspecies G. pilsbryi aukenensis is characterized by a
more prominent sulcus, the carina extended into a
knife-edge keel and in having slightly fewer and more
widely spaced radial ribs on the body whorl.
Description. — Shell of average size, with 6Vs rather loosely
coiled whorls. Spire elevated, depressedly dome shaped in outline,
last whorl deflected below periphery, H/D ratio 0.575. Embryonic
whorls lss, eroded, only remnants of heavy radial ribbing left.
Postnuclear whorls with moderately wide, protractively sinuated
radial ribs, 95 on the body whorl, whose interstices are usually 2-3
times their width. Microsculpture of extremely fine radial riblets and
finer spiral riblets, with very strong secondary spiral cording
developed on the shell base. Sutures very shallow, whorls rounded
above shallow supraperipheral sulcus, a protruded threadlike carina
which is beaded where radial ribs cross. Umbilicus with narrow oval
opening, expanded into brood chamber internally. Umbilical margin
sharp with an expanded inner portion. Color mainly leached from
shell, with regularly spaced, retractive, reddish flammulations
remaining. Aperture subtriangular with evenly rounded margins.
Parietal wall with 13 threadlike barriers anteriorly, 5 of which
become slightly and almost equally elevated posteriorly. Columellar
barrier a very high lamellar ridge, parallel to the plane of coiling,
with small recessed accessory denticles. Major palatal barriers 4,
with eight accessory traces: lower palatal a very short low thread;
palatals 2 and 3 relatively low lamellar ridges; upper palatal a thin,
high, V-shaped ridge slanted upward to point toward the upper
expanded parietal. Height of holotype 3.01 mm., diameter 5.23 mm.
Holotype. — Gambier Islands: Mangareva, Station
277, Mangareva Islet, vicinity of Ganhutu. Collected
on open ground by Donald Anderson on June 26, 1934.
BPBM 138979.
Range. — Mangareva Islet, Mangareva, Gambier
Islands.
Paratypes. — Same as list of material.
Material. — Mangareva: Mangareva Islet (Sta-
tions 142, 277) vicinity of Ganhutu (88 specimens,
BPBM 138948-50, BPBM 138979-80).
Remarks. — The ribbing of Gambiodonta pilsbryi
is intermediate in size between that of G. tumida and
G. mangarevana. It is easily separated from both on
the basis of its flatter spire, more rostrate periphery,
and 5 parietal barriers. The type is unusual in that the
Columellar barrier ends at, and not near, the apertural
edge.
At Station 277, Cooke and Kondo found only 1
specimen of G. tumida, 28 of G. mirabilis, and 62 of
G. pilsbryi pilsbryi; but at Station 142, Donald
Anderson collected 23 G. tumida, 7 G. mirabilis, and
26 G. pilsbryi pilsbryi. The two stations could not be
distinguished on a large scale map, yet obviously are
separated by at least 100-200 ft. in relation to the
shore line and by an unknown distance parallel to the
shore. Hence the difference in species abundance at the
two stations almost certainly represents differential
accumulation in the two deposits.
Great pleasure is taken in naming this species
after the late H. A. Pilsbry, dean of American
malacologists, and the foremost student of non-marine
mollusks.
Gambiodonta pilsbryi aukenensis, new subspecies
(Cooke & Solem). Figures 185; 187d-f.
Diagnosis. — Shell of average size, diameter 4.64-5.36 mm.
(mean 5.07 mm.), with 6-6% normally coiled whorls. Apex and spire
moderately elevated, slightly flattened above, last part of body whorl
only slightly deflected below periphery, H/D ratio 0.519-0.605 (mean
0.559). Umbilical opening irregularly oval, modified internally to
form brood chamber. Postnuclear sculpture of narrow, prominent,
strongly protractively sinuated radial ribs, 69-85 (mean 77.5) on the
body whorl, whose interstices are usually slightly more than twice
their width. Microsculpture typical, secondary spiral cording
strongest on shell base. Sutures shallow, whorls strongly rounded
above prominent supraperipheral sulcus, periphery of body whorl
strongly protruded into a threadlike keel. Aperture compressedly
ovate, strongly marked internally by peripheral protrusion, inclined
about 25° from shell axis. Parietal barriers 5, extending well beyond
line of vision, with five to eight accessory traces: 5 major barriers low
and threadlike for anterior one-quarter whorl, subequally and only
moderately elevated posteriorly, with 4th and 5th slightly lower than
upper three. Accessory traces very slender, scarcely distinguishable
anteriorly from terminal portions of major barriers. Columellar
barrier a high lamellar blade, with gradual anterior descension to
edge of columellar callus, lying parallel to plane of coiling, with at
most one deeply recessed columellar trace. Major palatal barriers 4,
deeply recessed, extending about three-sixteenths of a whorl, with six
to eight very inconspicuous accessory traces: lower palatal greatly
reduced in height, barely distinguishable from accessory trace: 2nd
and 3rd high and bladelike, with gradual anterior descension; 4th
supraperipheral in position, reduced in height, a V-shaped ridge lying
opposite upper parietal. Accessory palatal traces in normal position.
ab
cd
FIG. 187. a-c, Gambiodonta pilsbryi pilsbryi, new species. Station 277. Mangareva Islet, Mangareva, Gambier Islands. Holotype. BPBM
138979; d-f, Gambiodonta pilsbryi aukenensis, new subspecies. Station 88, Aukena Islet, Mangareva, Gambier Islands. Holotype. BPBM 138711.
Sculpture as shown in fig. f is normal, in fig. c with characteristic surface erosion on rib tops, both figures with microspirals and microradials
omitted. Scale lines equal 1 mm. Drawings by YK reproduced through the courtesy of Bernice P. Bishop Museum.
437
438
SOLEM: ENDODONTOID LAND SNAILS
Gambiodonta pilsbryi aukenensis differs from the
nominate subspecies found on Mangareva Islet in
several features: the peripheral keel is much more
strongly protruded, the ribbing on the body whorl is
more widely spaced and, on the average, fewer in
number; the diameter is very slightly greater (caused
by the greater protrusion of the peripheral keel) and
the H/D ratio is slightly lower (caused by the same
factor).
Description. — Shell of average size, with 6'/s normally coiled
whorls. Apex and spire moderately elevated, slightly flattened above,
last whorl not deflected below periphery, H/D ratio 0.519. Apical
whorls I'/a, sculpture partly eroded, with traces of broadly rounded
radial ribs remaining. Postnuclear sculpture of narrow, prominent,
strongly protractively sinuated radial ribs, 70 on the body whorl,
whose interstices are slightly more than twice their width.
Microsculpture of fine radial riblets, five to eight between each pair
of major ribs, crossed by barely visible and extremely crowded spiral
riblets, with a secondary sculpture of low rounded spiral cords,
becoming stronger on base of shell. Sutures shallow, whorls strongly
rounded above prominent supraperipheral sulcus, periphery strongly
protruded into a threadlike keel. Color mainly leached from shell,
with traces of irregular, broad, reddish flammulations remaining.
Umbilicus modified to form a brood chamber, closed by inward
growth of last whorl and a half, remaining opening irregularly ovate.
Aperture compressedly ovate, strongly marked internally by pe-
ripheral protrusion, inclined about 25° from shell axis. Parietal
barriers 5, extending posteriorly beyond line of vision, with four
accessory traces: major parietals threadlike for anterior quarter
whorl, weakly elevated and expanded posteriorly. Columellar barrier
a high bladelike ridge, parallel to plane of coiling, gradually
descending to edge of columellar callus, with a single deeply recessed
accessory trace. Major palatal barriers 4, deeply recessed, extending
posteriorly about three-sixteenths of a whorl, with six accessory
traces: lower palatal greatly reduced in height, scarcely larger than
neighboring accessory traces; 2nd and 3rd palatals high and
bladelike, with gradual anterior descension; 4th palatal supraperi-
pheral in position, reduced in height, a V-shaped ridge, lying opposite
upper parietal. Five palatal traces low and inconspicuous, trace
located between 2nd and 3rd palatals almost equal to them in height
and much larger than 1st palatal. Height of holotype 2.74 mm.,
diameter 5.36 mm.
Holotype. — Gambier Islands: Mangareva, Aukena
Islet, Station 88, near the gap. Collected along the
trail by Donald Anderson and C. M. Cooke, Jr., on
May 28, 1934. BPBM 138711.
Range. — Aukena Islet, Mangareva, Gambier
Islands.
Paratypes. — Same as list of material.
Material. -• Mangareva: Aukena Islet (Stations
82, 88, 102, 103) in the vicinity of the gap (79
specimens, BPBM 138686, BPBM 138711-2, BPBM
138760, BPBM 138801).
Remarks. -• While the heights of G. pilsbryi
pilsbryi and G. p. aukenensis are essentially identical
(table CVIII) the differences in diameter (with 53 df,
"t" = 4.6707) and H/D ratio ("t" = 3.0188) are highly
significant. The greater protrusion of the peripheral
keel noticeably increased the diameter and thus
lowered the H/D ratio in shells of the same height.
Specimens of G. pilsbryi aukenensis were taken in
quantity only at Station 88, where 96 examples were
found together with 197 Gambiodonta grandis and
two examples of G. mirabilis. The difference in
sculpture size is such that no confusion of juveniles is
possible. Single specimens of G. p. aukenensis were
found among the limited Gambiodonta material taken
at Stations 82, 102, and 103.
Gambiodonta mangarevana, new species (Solem &
Cooke). Figure 186c.
Diagnosis. — Shell small, diameter 4.38-4.58 mm. (mean 4.51
mm.), with 6% normally coiled whorls. Apex and spire strongly
elevated, somewhat rounded above, last whorl deflected strongly
below periphery, H/D ratio 0.657-0.715 (mean 0.686). Umbilical
opening irregularly oval, modified internally to form brood chamber.
Postnuclear whorls with high, narrow, prominent, strongly protrac-
tively sinuated radial ribs, 67-77 (mean 70.7) on the body whorl,
whose interstices are about twice their width. Microsculpture of fine
radial riblets, crossed by finer and much more crowded spiral riblets,
with prominent secondary spiral cording visible on base of shell and
near sutures. Sutures shallow, whorls strongly rounded above very
shallow supraperipheral sulcus, periphery slightly protruded into a
weak threadlike keel. Aperture ovate, without internal indication
of peripheral protrusion, inclined about 25° from shell axis. Parie-
tal barriers 4, extending posteriorly beyond line of vision, with six
or seven accessory traces: major parietals low and threadlike for
anterior quarter whorl, becoming strongly elevated and bulbously
expanded posteriorly, 3rd and 4th with elevated portion extending
further anteriorly. Normally traces located above 1st parietal, two
between 1st and 2nd, one between 2nd and 3rd, and one between 3rd
and 4th. Columellar barrier a high lamellar blade, parallel to plane
of coiling, with gradual anterior descension. A single columellar trace
located just above baso-columellar margin. Palatal barriers 4,
extending nearly one-quarter whorl, with five to seven accessory
traces: lower palatal greatly reduced in height, scarcely larger than
accessory traces; 2nd and 3rd palatals very high, bladelike, with
gradual anterior descension; 4th palatal supraperipheral, reduced in
height, a large V-shaped ridge lying opposite upper parietal.
Generally three palatal traces above 4th palatal, one between 3rd
and 4th, two between 2nd and 3rd, and one between 1st and 2nd.
The small size, quite narrow and regularly spaced
radial ribs, plus presence of basal radial ribs imme-
diately separate Gambiodonta mangarevana from its
larger relative, G. tumida. The higher dome-shaped
spire, presence of spiral cording above the periphery, 4
(instead of 5) major parietals, and relatively prominent
supraperipheral sulcus distinguish it from G. pilsbryi.
G. agakauitaiana is smaller, higher, with a much
deeper sulcus, and has only 3 major parietals.
Description. — Shell small, with 6% normally coiled whorls.
Apex and spire strongly elevated, apical portion somewhat flattened,
last part of body whorl strongly deflected below periphery, H/D
ratio 0.715. Embryonic whorls ls/e, with strong, broadly rounded
radial ribs, whose interstices are narrower than their width.
Remaining whorls with regularly spaced, relatively narrow, protrac-
tively sinuated radial ribs, 77 on the body whorl, whose inter-
stices are 2-3 times their width. Ribbing only slightly reduced on
base of shell. Microsculpture of numerous, fine, radial riblets, crossed
by much finer and more crowded spiral riblets, with a secondary
sculpture of low but regular rounded spiral cords. Spiral sculpture
most prominent on base of shell and in supraperipheral sulcus.
Sutures shallow, whorls strongly rounded above with very shallow
supraperipheral sulcus. Color mainly eroded from shell with a few
irregular, reddish-yellow flammulations remaining. Periphery of body
whorl with a very low rounded keel. Aperture subtriangular with
rounded margins. Parietal wall with 4 major barriers and seven
accessory traces, all extending beyond line of vision. Major barriers
SYSTEMATIC REVIEW
439
ab
t-
cd
FIG. 188. a-b, Gambiodon/a tumida, new species. Station 142, Mangareva Islet, Mangareva, Gambier Islands. Holotype. BPBM 138978; c-d,
Gambiodonta mirabilis, new species. Station 277, Mangareva Islet, Mangareva, Gambier Islands. Holotype. BPBM 138981. Scale lines equal 1
mm. Drawings by YK reproduced through the courtesy of Bernice P. Bishop Museum.
identical in structure to those of G. tumida. Columellar barrier a
high lamellate ridge, parallel to the plane of coiling, reaching the
apertural margin, with a small accessory trace below. Major palatal
barriers 4, with seven accessory denticles. Lower palatal reduced to a
small ridge; numbers 2 and 3 high and lamellate, broadly rounded
above; number 4 a deeply recessed, V-shaped ridge lying opposite the
upper parietal. Height of holotype 3.27 mm., diameter 4.57 mm.
Holotype. — Gambier Islands: Mangareva, Station
189, Mangareva Islet, north end of Rikitea. Collected
on open ground by Yoshio Kondo and C. M. Cooke,
Jr., on June 8, 1934. BPBM 141695.
Range. — Mangareva Islet, Mangareva, Gambier
Islands.
Paratypes. — Same as list of material.
Material. — Mangareva: Mangareva Islet (Sta-
tions 155, 182, 189) vicinity of Rikitea (5 specimens,
BPBM 9632, BPBM 139005, BPBM 141669, BPBM
141695).
Remarks. — Only two adults and four juveniles
were taken of this species. At first glance it appears to
be a miniature form of Gambiodonta tumida, but the
character of the ribbing is quite different in the two
species (figs. 188a; 186c). The holotype is subcarinate
on the body whorl, but the other adults and the
juveniles are almost as strongly rostrate as in G.
pilsbryi pilsbryi. The height of the major parietal
barriers is intermediate between that of G. mirabilis
and the much lower G. pilsbryi.
440
SOLEM: ENDODONTOID LAND SNAILS
Only scattered individuals were collected, three
specimens from Station 155, one from Station 187, and
two from Station 189. No other Gambiodonta were
collected at these stations, which are well removed
geographically from the area where other Mangareva
Islet Gambiodonta were obtained.
Gambiodonta mirabilis, new species (Cooke &
Solem). Figures 22a-b; 188c-d.
Diagnosis. — Shell larger than average, diameter 5.03-5.75 mm.
(mean 5.54 mm.), with 5-5% normally coiled whorls. Apex and early
spire flat or slightly depressed below level of antepenultimate whorl,
later whorls descending sharply, H/D ratio 0.552-0.694 (mean 0.612).
Umbilical opening irregularly ovate, modified internally to form
brood chamber. Postnuclear whorls with prominent, narrow, rather
widely spaced, strongly protractively sinuated radial ribs, 38-56
(mean 45.5) on the body whorl, whose interstices are 3-4 times their
width, and which denticulate the supraperipheral keel, are reduced in
height before denticulating peripheral keel, and are reduced to
irregularity and very small size on the base of shell. Microsculpture
of fine radial riblets crossed by much finer and more crowded spiral
riblets, combined with irregular growth wrinkles. No secondary spiral
cording. Sutures very shallow, whorls flattened or slightly concave in
areas between three prominent keels: supraperipheral most
protruded, slightly above midpoint between periphery and suture;
peripheral keel strongly but narrowly protruded, also denticulated by
crossing of major radial ribs; subperipheral keel located little less
than halfway between periphery and edge of umbilical opening,
much lower and more threadlike than preceeding two keels. Aperture
pentagonal, strongly marked internally by protrusion of keels,
inclined about 25° from shell axis. Major parietal barriers 2,
extending posteriorly beyond line of vision, usually with six to eight
accessory traces: upper parietal situated on top of subperipheral keel,
low and threadlike for anterior three-sixteenths of a whorl, very
strongly elevated and expanded above posteriorly to beyond line of
vision; 2nd parietal similar in height, posterior portion slightly
shorter and more recessed than 1st; parietal traces located normally
three above upper parietal, two between the major parietals and one
to three below major parietals. The 3rd parietal found in other
species only a threadlike trace in G. mirabilis. Columellar barrier a
high bladelike ridge, expanded and serrated above, parallel to plane
of coiling, with one lower accessory denticle. Major palatal barriers
3, moderately recessed, extending posteriorly almost one-quarter
whorl, with seven to twelve accessory traces; lower palatal of other
Gambiodonta absent; "2nd" palatal high and bladelike with
gradually curved anterior descension; "3rd" palatal higher with lower
gradual anterior descension, more prominently flattened and ex-
panded on top; "4th" palatal reduced in height, supraperipheral in
position, a highly elevated V-shaped ridge. Palatal traces very
inconspicuous, normal in position.
The triple keels of Gambiodonta mirabilis are
unique in the Endodontidae and immediately separate
this species from all Polynesian taxa. In having only 2
elevated parietals, a flat or depressed apex and less
than six whorls, G. mirabilis is clearly separated from
the other Gambiodonta.
Description. — Shell of slightly larger than average size with 5%
whorls. Spire flat above, rapidly descending from third whorl on,
H/D ratio 0.588. Embryonic whorls l'/2, sculpture of quite wide,
irregularly rounded radial ribs, a few fine radial riblets visible
between. Remaining whorls with widely spaced, relatively prominent,
protractively sinuated radial ribs, 41 on the body whorl, whose
interstices are about three or four times their width and that
denticulate the upper two keels upon crossing them. Microsculpture
of fine radial riblets, crossed by finer spiral riblets, no secondary
cording. Sculpture prominent above keels, reduced in central sulcus
and greatly reduced to absent on the base. Sutures very shallow,
whorls flattened above, concave between keels. All whorls with a
very high ridgelike supraperipheral keel, strongly beaded by radial
ribs crossing; a slightly less prominent and less beaded subperipheral
keel with the area between flattened; and a much lower threadlike
basal keel with the whorls flattened both above and below it.
Umbilicus with small ovate opening greatly expanded inside to form
brood chamber. Color mainly absent from shell although some
sinuate, reddish-brown flammulations remain. Aperture pentagonal,
interiorly strongly marked by keel protrusion, inclined about 20°
from shell axis. Parietal wall with 2 major barriers and four
accessory traces: uppermost 2 parietals with threadlike traces
extending beyond line of vision; major 2 parietals threadlike for
anterior half, becoming quite high and lamellate after first three-
sixteenths whorl, 1st parietal arising from thread of subperipheral
keel; two lower parietal traces slightly elevated posteriorly. Colu-
mellar barrier a high lamellate ridge, parallel to plane of coiling,
reaching apertural margin with accessory denticle below. Major
palatal barriers 3, with twelve accessory traces: lower 2 palatals
relatively high and lamellate, gradually descending to apertural edge;
3rd palatal a V-shaped ridge lying opposite the upper major parietal,
somewhat recessed within aperture. Height of holotype 3.27 mm.,
diameter 5.50 mm.
Holotype. — Gambier Islands: Mangareva, Station
277, vicinity of Ganhutu, Mangareva Islet. Collected
on open ground by Donald Anderson on June 26, 1934.
BPBM 138981.
Range. — Aukena and Mangareva Islets, Man-
gareva, Gambier Islands.
Paratypes. — Same as list of material.
Material. — Mangareva: Mangareva Islet (Sta-
tions 142, 277) vicinity of Ganhutu (35 specimens,
BPBM 138951-2, BPBM 138981); Mangareva Islet
(Station 197) northeast of Vaituatai Bay (2 specimens,
BPBM 139018); Aukena Islet (Stations 82, 88) vicinity
of the gap (4 specimens, BPBM 138687, BPBM
138708).
Remarks. — The few specimens from Vaituatai
Bay on Mangareva and near the gap on Aukena Islet
do not differ in any significant respects from the
Ganhutu types. Once seen, the shape of the whorls of
Gambiodonta mirabilis is unforgettable. No other
Pacific Island endodontid can be confused with it.
Apparently, the great alterations in whorl
contours produced by the addition of two keels had
marked effects on the apertural barriers. The 2 major
parietals are elevated at least twice the height found in
other Gambiodonta, while the parietal trace occupying
the position of the 3rd parietal shows a very slight
posterior elevation and unquestionably is homologous
with the lower parietal in other Gambiodonta. No
posterior elevation was detected in either of the upper
parietal traces. The basal portion of the palatal wall is
obviously modified in contour and the lower palatal
barrier of other Gambiodonta cannot be detected in G.
mirabilis. The 3 major palatals present correspond
exactly in position to the 2nd, 3rd, and 4th palatals of
other species.
The startling appearance of G. mirabilis is not
indicative of any great phylogenetic distance, since the
barrier changes seem to be results of the two keel
SYSTEMATIC REVIEW
441
addition and could be thus a relatively minor genetic
shift.
Only four specimens were found on Aukena
(Stations 82, 88) and two from Vaituatai Bay,
Mangareva Islet (Station 197). At the latter locality
nine G. tumida were collected. At Station 277, G.
mirabilis was second in number to G. pilsbryi
pilsbryi, but at Station 142 was represented by much
fewer individuals than either G. tumida or G. pilsbryi
pilsbryi.
Gambiodonta tumida, new species (Cooke & Solem).
Figure 188a-b.
Diagnosis. — Shell relatively large, diameter 5.88-6.41 mm.
(mean 6.18 mm.), with 6-6% tightly coiled whorls. Apex and spire
very strongly elevated, broadly rounded above, last portion of body
whorl deflected slightly below periphery, H/D ratio 0.604-0.758
(mean 0.702). Umbilicus irregular in outline, internally modified to
form brood chamber. Postnuclear sculpture of prominent, low,
broadly rounded, strongly protractively sinuated radial ribs, 53-66
(mean 60.6) on the body whorl, whose interstices are much less than
twice their width, and which are absent from base of shell.
Microsculpture occasionally visible as low, broadly rounded radial
riblets, four to six between each pair of major ribs, with exceedingly
fine spiral ribbing barely visible under 96 x magnification. Strong
secondary spiral cording primarily visible on base of shell and above
shallow supraperipheral sulcus. Sutures shallow, whorls strongly
rounded above the broad and shallow supraperipheral sulcus,
periphery slightly protruded into a threadlike keel. Aperture
subovate, peripheral protrusion weakly reflected internally, inclined
about 25° from shell axis. Parietal barriers 4, extending well beyond
line of vision, with six to eight threadlike accessory traces: major 4
parietals with anterior one-quarter whorl low and threadlike,
becoming suddenly elevated almost beyond line of vision, elevated
portions high and bladelike. weakly expanded above, lower with
elevated portion longer and reaching further anteriorly than upper
parietals; one or two parietal traces located between each pair of
major barriers with two or three above upper parietal and
occasionally one below 4th parietal. Columellar barrier a high
bladelike ridge, parallel to plane of coiling, with gradual anterior
descension, a single accessory trace just above baso-columellar
margin. Palatal barriers 4, extending three-sixteenths of a whorl,
rather deeply recessed, with four to six accessory traces: lower
palatal greatly reduced in height, a little larger than accessory traces,
only slightly recessed; 2nd and 3rd palatal barriers high lamellar
blades, with very gradual anterior descension; 4th palatal suprape-
ripheral in position, a high V-shaped ridge with very gradual anterior
descension, posterior portion lying opposite elevated 1st parietal.
Accessory traces normally located between 1st and 2nd, 2nd and 3rd,
3rd and 4th, with two above 4th palatal.
The comparatively large size, very high spire, wide
ribs, 4 parietals, and weak supraperipheral sulcus
separate Gambiodonta tumida from the other species.
G. pilsbryi has 5 weakly elevated parietals and a
sharply protruded periphery, while G. mangarevana
and G. agakauitaiana are more than 1 mm. smaller
and differ in many details of sculpture and barrier
characteristics.
Description. — Shell quite large, dome shaped, with 6!4 tightly
coiled whorls. Apex and spire greatly elevated, rounded above, last
whorl strongly deflected below periphery, H/D ratio 0.717. Embry-
onic whorls l'/2, partially eroded, with some traces of the heavy
radial ribs remaining. Postnuclear whorls with low, broad, somewhat
vague, strongly protractively sinuated radial ribs, about 62 on the
body whorl, vhich are absent from the shell base. Microsculpture of
low, broad, rounded radial riblets, extremely fine spiral riblets and a
secondary sculpture of high and prominent spiral cords, which are
most developed on shell base. Sutures shallow, whorls strongly
rounded above broad and shallow supraperipheral sulcus. Periphery
of body whorl with a slightly protruded threadlike carination, with
the ribs continuing over and forming slight knobs on the keel.
Umbilicus with a relatively narrow, oval opening, broadly expanded
internally to form a brood chamber. Color partially eroded from
shell, with large, irregular, reddish-yellow flammulations remaining.
Aperture triangular, somewhat rounded above and below periphery,
no internal evidence of peripheral keel. Parietal wall with 4 major
barriers, extending well beyond line of vision, and six accessory
traces: major parietals posteriorly elevated, 3rd and 4th with
posterior elevation longer and extending further anteriorly. Ac-
cessory traces very narrow and low; anteriorly not separable from
major barriers. Columellar barrier a broad lamellate ridge, crossing
umbilical callus and reaching apertural margin. Junction of
columellar and basal lips marked by broad groove, dipping down to
the ridged umbilical margin. A small, recessed barrier (columellar) is
located slightly above the middle of groove. Palatal barriers 4, deeply
recessed, extending three-sixteenths of a whorl: lower a much
reduced threadlike ridge. Middle 2 moderately high, elongate; upper
a narrow V-shaped ridge situated opposite the upper expanded
parietal. Palatal traces 5, low and inconspicuous, between 2nd and
3rd, 3rd and 4th palatals, with three above 4th palatal. Height of
holotype 4.31 mm., diameter 6.02 mm.
Holotype. — Mangareva: Station 142, Mangareva
Islet, vicinity of Ganhutu. Collected on open ground
by Donald Anderson on June 26, 1934. BPBM 138978.
Range. — Mangareva Islet, Mangareva, Gambier
Islands.
Paratypes. — Same as list of material.
Material. — Mangareva: Mangareva Islet (Sta-
tions 142, 277) vicinity of Ganhutu (24 specimens,
BPBM 9706, BPBM 138947-8, BPBM 138978, ex
BPBM 138979); Mangareva Islet (Station 197)
northeast of Vaituitai Bay (9 specimens, BPBM
139016-7).
Remarks. — Only adult specimens of G. tumida
were found. Gambiodonta pilsbryi was collected in
quantity at Stations 142 and 277, but all young
specimens were referable to the latter. There is no
problem in separating the two species (table CVII),
since in G. pilsbryi the radial ribs are very narrow and
regularly spaced while in G. tumida they are low and
very broadly rounded. The absence of young G. tumida
is puzzling, as is the difference in abundance (one
specimen at Station 277 and 23 at Station 142).
Gambiodonta tumida seems to be most closely related
to G. mangarevana from the Rikitea area, which
differs in its much smaller size (mean diameter 4.51
mm.) and its narrow and regular ribbing.
Gambiodonta grandis, new species (Cooke & Solem).
Figure 189a-e.
Diagnosis. — Shell extremely large, diameter 10.9-13.4 mm.
(mean 12.26 mm.), with 6'/<-8 relatively tightly coiled whorls. Apex
and spire very strongly and almost evenly elevated, slightly rounded
above, last whorl not descending more rapidly, H/D ratio 0.509-0.721
(mean 0.591). Umbilical opening very narrow, irregularly ovate,
modified internally to form brood chamber. Postnuclear sculpture of
wide, very prominent, rounded, somewhat irregular radial ribs. 46-65
(mean 56.7) on the body whorl, whose interstices are less than twice
442
SOLEM: ENDODONTOID LAND SNAILS
FIG. 189. Gambiodonta grandis, new species: a-b, Station 88, Aukena Islet, Mangareva, Gambier Islands. Holotype. BPBM 138709; c,
paratype from Station 88, showing length and form of parietal lamellae. BPBM 138709; d-e, juvenile paratype from Station 88 showing form of
young shell. BPBM 138710. Scale lines equal 1 mm. Fig. c greatly enlarged. Drawings by YK reproduced through the courtesy of Bernice P.
Bishop Museum.
their width, and which are absent from base of shell. Radial and
spiral microsculpture typical, no secondary cording developed.
Sutures shallow, whorls strongly rounded down to supraperipheral
sulcus, periphery protruded into a strong threadlike keel. Aperture
ovate, strongly marked internally by peripheral protrusion, inclined
about 25° from shell axis. Major parietal barriers 4, extending
posteriorly beyond line of vision, occasionally with one accessory
trace: upper parietal a raised threadlike ridge for entire length; 2nd,
3rd, and 4th parietals have anterior portions raised threadlike ridges,
becoming strongly elevated and slightly expanded above posteriorly
(fig. 189c). Columellar barrier high and bladelike, parallel to plane of
coiling, with gradual anterior descension to edge of columellar callus,
plus one very deeply recessed accessory denticle. Major palatal
barriers 3, deeply recessed, extending about one-eighth whorl, with
two to four very inconspicuous accessory traces: normal lower
palatal often not detectable as such, at largest smaller than upper
SYSTEMATIC REVIEW
TABLE CVIII. - LOCAL VARIATION IN GAMBIODONTA
443
Name
agakaultalana
BPBM 138903
Number of
Specimens
Height
2.70±0.050
(2.52-2.85)
Diameter
4.01±0.021
(3.94-4.07)
H/D Ratio
0.675±0.0139
(0.633-0.716)
Whorls
6 1/8+
(6-6 3/8)
ptlsbryl pllsbryl
BPBM 138979, -48, -50
37
2.83±0.026
(2.35-3.14)
4.86±0.026
(4.51-5.29)
0.582+.0.0046
(0.514-0.652)
6 3/4-
(6 1/8-7 1/8)
pllsbryl aukenensls
BPBM 138711
18
2.81±0.027
(2.61-3.01)
5.04±0.008
(4.64-5.40)
0.559±0.0052
(0.519-0.605)
6 3/8-
(6-6 5/8)
mangarevana
BPBM 141695, BPBM 139005
'
3.07±0.196
(2.88-3.27)
4.48±0.098
(4.38-4.58)
0.686±0.0290
(0.657-0.715)
6 5/8
mirablUs
BPBM 138981, -51, -52
18
3.37±0.059
(3.07-3.86)
5.50±0.047
(5.03-5.75)
0.612±0.0085
(0.552-0.694)
5 3/8-
(5-5 7/8)
tumida
BPBM 138947, -78
16
4.31±0.073
(3.59-4.71)
6.14±0.054
(5.88-6.60)
0.702±0.0103
(0.604-0.758)
6 1/2-
(6-6 3/4)
grandls
BPBM 138709
73
7.36±0.069
(5.90-8.70)
12.30±0.067
(10.90-13.40)
0.597±0.0052
(0.511-0.721)
7 3/8+
(6 1/2-8)
BPBM 138904
6.24±0.152
(5.60-6.80)
11.65±0.198
(11.00-12.50)
0.535±0.0057
(0.509-0.558)
6 5/8+
(6 1/4-7 1/8)
traces; "2nd" and "3rd" palatals high lamellar blades, weakly
expanded above, with less gradual anterior descension; "4th"
supraperipheral, reduced in height, a V-shaped lamellar ridge.
Palatal traces usually one between each pair of major palatal
barriers, trace between 3rd and 4th palatal sometimes equal in size to
3rd palatal.
The very great size, many whorls, wide radial ribs,
very deeply recessed palatal barriers, and almost total
absence of accessory traces separate Gambiodonta
grandis from the other species of the genus. Two
extralimital species of similar size might be confused
with it: Pseudolibera lillianae from Makatea has only
a single parietal and no palatal barriers, while
Nesodiscus magnificus from Borabora has a broadly
open umbilicus, no radial sculpture, and only a single
parietal.
Description. — Shell very large, with 8 tightly coiled whorls.
Apex and spire very strongly and almost evenly elevated, slightly
rounded above, last whorl deflected slightly below periphery, H/D
ratio 0.721. Embryonic whorls I1 2, with very wide, prominent radial
ribs, microsculpture eroded. Postnuclear whorls with heavy, rounded,
protractively sinuated radial ribs, about 85 on the body whorl, whose
interstices are slightly wider than their width, and which are absent
from shell base. Microsculpture of irregular growth lines between
major ribs, continued as irregular wrinkles on base of shell. No
secondary spiral cording. Sutures shallow, whorls slanting down to
prominent supraperipheral sulcus, periphery strongly protruded into
threadlike keel. No color pattern present. Umbilical opening
irregularly ovate, expanded internally to form brood chamber.
Aperture compressedly ovate, strongly marked internally by peri-
pheral protrusion, inclined about 25° from shell axis. Major parietal
barriers 4, extending posteriorly beyond line of vision, with one short
anterior accessory trace: upper parietal threadlike for entire length;
2nd and 3rd threadlike for first quarter whorl, becoming strongly
elevated posteriorly and slightly expanded above (as in fig. 189c); 4th
with posterior elevated portion slightly lower and shorter than in
3rd. Accessory trace located above upper parietal at anterior end,
very short. Columellar barrier a high, bladelike ridge with gradual
anterior descension, lying parallel to plane of coiling, twisted slightly
upward at apertural margin. Major palatal barriers 3, extending
about one-eighth whorl, very deeply recessed, with three very
inconspicuous accessory traces: lower palatal of normal Gambio-
donta absent; "2nd" and "3rd" moderately elevated barriers with
gradual anterior descension; "4th" supraperipheral, reduced in
height. One palatal trace below lower palatal, one between each pair
of palatals. Height of holotype 8.5 mm., diameter 11.8 mm.
Holotype. — Gambier Islands: Mangareva, Station
88, Aukena Islet along trail near gap. Collected on
open ground by D. Anderson and C. M. Cooke, Jr., on
May 28, 1934. BPBM 138709.
Range. — Aukena and Agakauitai Islets, Man-
gareva, Gambier Islands.
444
SOLEM: ENDODONTOID LAND SNAILS
Paratypes. — Same as list of material.
Material. — Mangareva: Aukena Islet (Stations
82, 88, 102, 103) in vicinity of gap (227 specimens,
BPBM 138685, BPBM 138709-10, BPBM 138758-9);
Agakauitai Islet (Station 195) on northwest side (32
specimens, BPBM 138800, BPBM 138904).
Remarks. — This magnificent species was quite
common on Aukena Islet at the gap. Specimens were
lying in the open and many had been partially crushed
or abraded by rain and the feet of passing natives.
The specimens from Agakauitai were mainly
subadult, but the few adult shells fall within the range
of variation of the type set although averaging smaller
in size and lower in H/D ratio (table CVIII). With 79
df, "t" equals 3.0668 for diameter and 3.9362 for H/D
ratio, indicating highly significant differences. They
are indistinguishable in sculpture and dentition. The
figured type is the highest specimen examined, but is
in magnificent condition. Although atypical, it can
best represent this species. More than in most
Gambiodonta, the lower palatal is reduced to the
identical size of neighboring traces, and the palatal
traces between the 2nd and 4th palatals often become
greatly enlarged, occasionally equalling in size and
shape the major barriers themselves. Time did not
permit cleaning of most apertures and a study of
palatal barrier variation in G. grandis would be an
interesting minor project.
The general appearance of G. grandis is most
similar to Libera jacquinoti, which differs very
obviously in barriers and size (fig. 179d-f).
Genus Thaumatodon Pilsbry, 1893
Man. Conchol., (2), 9, p. 26.
Endodontidae with typical apical sculpture and microsculpture,
secondary spiral cording developed only in decemplicata and
corrugata. Postnuclear sculpture of narrow to very wide (hys-
tricelloides, vai'auensis, euaensis) radial ribs, with a pronounced
tendency toward great reduction of ribbing on body whorl
(hystricelloides, euaensis) or over entire spire (subdaedalea, corru-
gata). Apex and spire flat or slightly elevated (laddi, corrugata.
spirrhymatum, decemplicata) to markedly elevated (hystricelloides.
subdaedalea, cai-auensis, euaensis). body whorl descending slightly
to moderately, mean H/D ratio 0.494-0.535 (except 0.600-0.670 in
hystricelloides, cai'auensis, euaensis). Body whorl usually rounded
or laterally compressed, bikeeled in spirrhymatum. Whorls 5-51/2,
except laddi (4+1 and multilamellata (6*4). Umbilicus rather widely-
open, slightly narrowed (hystricelloides). or secondarily narrowed
(euaensis). Major parietals 3 or 4, with straight or twisted
(hystricelloides), small (subdaedalea) to large (hystricelloides)
serrated beads above, or crystalline barbs (multilamellata). Several
accessory traces present except in multilamellata and decemplicata.
Columellar barriers 1 or 2, parallel to or slanting downwards from
plane of coiling. Palatal barriers 3 to 6, normally 4, (except 5 in
multilamellata and decemplicata', 3 in vavauensis), regularly beaded
above (hooks in multilamellata), accessory traces present only in
spirrhymatum, hystricelloides. rai'auensis, and euaensis. Pallial
region typically endodontid. except for greater development of rectal
kidney arm. Hermaphroditic duct convoluted for quarter to half of
length, except in spirrhymatum. Talon a short, untapered to tapered
nub on carrefour. Uterus with clear division into four zones. Vas
deferens entering epiphallus through a valve. Epiphallus about one-
quarter to one-half length of penis, internally with two pilasters that
continue into penis, variously splitting. Penial retractor originating
on diaphragm, inserting directly onto penis-epiphallus junction.
Spermatheca inserting on penial side of penioviducal angle.
Type species. — Pitys multilamellata Garrett, 1872
(original designation).
Originally described as a subgenus of Endodonta,
by inertia Thaumatodon has been applied, usually in a
subgeneric sense, to any non-carinated endodontid
with apertural barriers from Polynesia, Micronesia, or
Hawaii that was not referred to Endodonta, Neso-
discus, Nesophila, or Libera. Its type species has not
been dissected. For the reasons outlined below under
the discussion of Thaumatodon multilamellata, I have
no hesitation in using this generic name for what
seems to be an anatomically compact and highly
distinctive group of species from the southwestern
fringes of Polynesia.
Both anatomical and conchological structures ally
Thaumatodon to the Palau Island Aaadonta, while
the Lau Archipelago monotypic genera Zyzzyxdonta
and Priceconcha are obvious derivatives, most
probably from the subdaedalea group of Thaumato-
don. In ornamentation of the apertural barriers and
structures of the terminal male genitalia, so far as is
known, these genera are highly specialized in
comparison with the remaining Endodontidae. The
major anatomical differences are development of an
epiphallic zone, with valvular entrance of the vas
deferens, found only in Aaadonta, Priceconcha, and
Thaumatodon, compared with the apical or subapical
direct entrance of the vas deferens into the penis found
in all other Endodontidae. This is the largest
morphologic change in the genitalia found in the
subfamily. I consider these three genera, plus Zyzzyx-
donta, to be the most advanced Pacific Island
Endodontidae. The insertion of the spermathecal shaft
on the penis has occurred elsewhere as a secondary
modification (Rhysoconcha), but is almost as unique
an event.
While obviously more closely interrelated than
related to other genera, Aaadonta and Thaumatodon
show numerous differences. Thaumatodon has typical
endodontid apical sculpture; Aaadonta has only the
spiral sculpture. Thaumatodon has the shell periphery
laterally compressed or compressed above and below a
rounded periphery except in T. spirrhymatum; Aaa-
donta, a periphery with protruded threadlike keel
(except A. pelewana). Thaumatodon has major radial
sculpture on at least part of the shell, with only T.
subdaedalea and T. corrugata showing marked reduc-
tion; Aaadonta has all major ribbing lost, with only
microradials remaining. Thaumatodon has a widely
open umbilicus (secondarily narrowed in T. euaensis)',
Aaadonta, a much narrower umbilicus (secondarily
widened in A. angaurana and A. kinlochi). Thaumato-
don has the spire slightly to moderately elevated (only
in T. euaensis does the height of spire approach half
CM
T'
CO
u
0|
-*
rH
I
CO
o
Q
bd
>H
S]
g
<
£
I
co'
CO
Co'
CO
CO
CO
CM'
&
CO
co°
CO
co'
CO
co"
10
CM
O
O
EH
s
O
o
W
K
X
H
O
w
pa
EH
Q
E
u
E
a)
s
CO
0>
CM
CO
CO
c-
CO
CD
CO
oa
CO
O
O
CO
CO
"^
•^
10
lO
CO
•^
lO
^
O
o
o*
o
CD
o
o
o
vo"
co"
co'
^
CD"
oS"
co"
co"
CO
CO
CO
rH
CD
o
rH
t-H
lO
IO
CO
CD
CD
lO
lO
lO
o
0
o
O
o
o
o
CD
IT-
CO
s
3
CO
o
IO
o
CO
CO
<N
^r
CO
CO
CO
ro
CN
1
1
I
IO
o
CO
i-H
CO
CO
CO
Oi
no
Oi
CM*
CN
CM*
CM*
CM*
CM"
(N
rH
£?
^f
co"
o^
^r
^f
r—
io"
CO
CO
CO
c—
lO
CN
OT
rH
CO
CM
CO
CM
CM"
CO*
"
CM*
o
CM"
rH
CO
Oi
rH
rH
CM*
rH
oo
rH
Oi
IO
rH
CO
CM
rH
i
1
1
<rt«
0>
10
CO
O
CO
CO
"*.
.
CO
10
10
*
0>
^
g-
CM"
^0
oT
sj-
S"
cS'
CO
*
"*
CO
CD
CO
10
rH
rH
CM
CO
K-
Q
1
UJ
0?
CM*
ff^
^_^
CO
^
u
f~^
1
3
10"
CN
i
10
CO
CM-
CO"
CO
o
t-
co
CO
io"
t-
Q
UJ
u
Q
21.
Q
u
Q
Q
OS,
UJ
O
rH
CM
1
O
CO
rH
o
rH
c-
10
s
S
Ol
rH
CO
CO
co
o
c~
rH
IO
00
c-
rH
1-1
"*
CN
rH
nj
cd
nj
1)
r- 1
ra
"O
Oj
4>
o
Q
_M
^
E
5
|
U
o
c
UJ
3
G
1>
rt
oo
*3
6
S
I)
T3
M
fTj
euae
T3
o
0
1
CO
CO
CO
o
z
445
446
SOLEM: ENDODONTOID LAND SNAILS
the body whorl width); Aaadonta has the spire
markedly elevated, except for the secondarily altered
A. kinlochi and A. fuscozonata depressa. Thaumato-
don generally has 4 major parietals, with a tendency
toward reduction or loss of the 2nd, and (usually)
accessory traces; Aaadonta has 3 parietals, reduced to
2 in A. irregularis, and rarely has accessory traces.
Thaumatodon, in the retracted specimens dissected,
has a much greater development of the rectal kidney
arm than does Aaadonta. Thaumatodon has a some-
what shorter epiphallus than Aaadonta, and Thau-
matodon has the talon very short and blunt-tipped,
while in Aaadonta it is long and tapering. In
Thaumatodon the atrium is distinctly shorter than in
Aaadonta.
Despite the recitation of differences, mostly
concerning normally variable characters, the devel-
opment of the beading on the apertural barriers and
division of the penis into an epiphallus and penis,
structures unique to the Pacific Island Endodontidae,
indicate a monophyletic origin for Aaadonta and
Thaumatodon.
Within Thaumatodon, patterns of variation are
correlated with geography in a classical radiating
pattern. The distribution (fig. 190) of individual species
is limited: one in the Ellice Islands living on Vaitupu
and Nukufetau (decemplicata); one on Rarotonga in
the Cook Islands (multilamellata); one on Upolu,
Western Samoa (hystricelloides); two in Tonga — T.
euaensis on Eua Island and T. vavauensis on Vavau;
and four in the Lau Archipelago of Fiji — T.
subdaedalea on Mango, Vanua Mblavu, and
Kimbombo Islands, T. corrugata on Mango Island, T.
spirrhymatum on Thithia, and T. laddi on Wangava.
The species at the northern and eastern limits of
distribution (decemplicata and multilamellata) are, in
most respects, the least specialized. Both species retain
major radial ribs of typical shape and size over the
entire body whorl, but are slightly unusual in that the
ribs are quite crowded with 12.44 and 10.90 ribs/mm.,
respectively. They both have 4 parietals, 5 palatals,
and lack accessory traces. The spire height is only one-
fifth to one-quarter the body whorl width, while the
umbilicus is widely open with typical decoiling
patterns. T. decemplicata is specialized only in
developing weak secondary spiral cording; T. multila-
mellata shows the dramatic change of developing
hooked denticles or pointed barbs (fig. 192d-e) on the
palatal barriers. Otherwise, both species are very
similar in appearance to the less specialized Mau-
todontha (Garrettoconcha), such as M. consobrina or
M. maupiensis.
Species from the middle part of the range, Tonga
and Samoa, are modified in several aspects that form a
unitary pattern, but each species shows a few
individual peculiarities. They agree in having quite
elevated spires and correspondingly large H/D ratios
(table CIX) with major ribbing that is very wide and
prominent on the spire and early part of the body
whorl. Only in T. vavauensis does the ribbing continue
at full size to the apertural edge, while in T.
hystricelloides it is partly reduced and in T. euaensis it
is greatly reduced on the last part of the body whorl.
Parietal barriers number 4 in T. hystricelloides, with
two accessory traces and peculiarly (fig. 194d) twisted
superior beading; the 2nd parietal is greatly reduced or
absent in T. euaensis with many accessory traces and
simple, rather prominent beading; and there are only 3
major parietals in T. vavauensis (2nd of other species
reduced to a threadlike trace), with up to four
accessory traces and simple beading. Palatal barriers
either number 4, with either a few (euaensis) or many
(hystricelloides) accessory traces, or vary from 3 to 4
with usually two accessory traces (vavauensis). The
umbilicus is about as widely open in vavauensis as in
the more generalized species, but fairly narrow in T.
hystricelloides, and secondarily greatly narrowed in T.
euaensis. Despite the twisted beading of hystricelloides
and the wide umbilicus of vavauensis, the common
pattern of spire elevation, unusual ribbing and pro-
liferation of accessory apertural traces provides a
marked contrast to the structures seen in the other
species.
The four species from the Lau Archipelago of Fiji,
T. laddi, T. spirrhymatum, T. corrugata, and T.
subdaedalea, are more specialized and have a different
pattern of specialization than those previously dis-
cussed. The spire is relatively low, with the umbilicus
wider and the H/D ratio lessened (table CIX); the
major sculpture is very fine and crowded (laddi),
enlarged and crowded (spirrhymatum), or very widely
spaced on the spire and drastically reduced on the
body whorl (corrugata and subdaedalea); the colu-
mellar barrier is slanted downward from the plane of
coiling (corrugata and subdaedalea), parallel to the
plane of coiling (spirrhymatum), or parallel to the
plane of coiling with the 1st palatal moved to the
baso-columellar margin (laddi). In general appearance,
they are closer to decemplicata and multilamellata,
but the presence of numerous parietal traces and
distinct sculptural modifications readily separate the
two patterns of modification. T. laddi is much more
similar to T. decemplicata than the other three, has 4
parietals as does decemplicata, but in shape and
umbilical width is more allied to subdaedalea and
corrugata. Since Wangava Island, the only known
locality for laddi, is in a quite different part of the Lau
Archipelago from the localities for corrugata and
subdaedalea, I am not surprised at the differences.
Collecting efforts in the Lau Archipelago and the
Ha'apai Group of Tonga, in particular, might yield
additional species of Thaumatodon. The Bishop Mu-
seum collections made in the Lau Archipelago in the
middle of 1938 apparently were during drought
conditions and many islands were not visited. No
material has been taken in the Ha'apai Group of
Tonga since a few specimens found by Graeffe in the
middle 1800's.
447
448
SOLEM: ENDODONTOID LAND SNAILS
Presently known specimens thus offer a clear
pattern of the most generalized species in the outer
areas of distribution (Ellice Islands and Rarotonga)
and a rather closely allied, strikingly modified complex
in a middle zone (Samoa and Tonga). A very
differently modified complex that produced two gener-
ically distinct derivatives (Zyzzyxdonta and Price-
concha) are found in a narrow "core" region (Lau
Archipelago). While it is extremely doubtful that
Thaumatodon originated in the Lau Archipelago, I
consider it probable that Lau represents the last
remaining segment of the central primitive Thaumato-
don range. The major islands of Fiji and possibly the
Bismarck-New Guinea area represent regions in which
Thaumatodon or Thaumatodon-derivative groups have
been replaced by Charopidae or helicarionid taxa. The
Ellice and Cook Islands represent the furthest and
probably latest expansion of Thaumatodon, with
Tonga and Samoa containing a unitary, more ad-
vanced stock than the outer fringe areas. Present data
are insufficient to determine whether the Lau Archi-
pelago Thaumatodon are either more or less advanced
or more or less specialized than the Samoa-Tonga
species. The probable directional movements of coloni-
zation are shown in Figure 190.
Anatomical variation between the four dissected
species, T. hystricelloides, T. euaensis, T. spirrhyma-
tum, and fragments of T. decemplicata was minor,
concerning primarily the proportionate lengths of the
penis and epiphallus. In T. euaensis, the epiphallus is
about half the penis length; in the other three species
it is only one-quarter to one-third. T. decemplicata, T.
spirrhymatum, and T. hystricelloides agree in pilaster
pattern, T. euaensis has one pilaster grossly enlarged
to form a stimulatory pad.
KEY TO THE GENUS Thaumatodon
1. Body whorl not keeled 2
Body whorl with a very strong peripheral and prominent
supraperipheral keel; Lau Archipelago, Fiji.
Thaumatodon spirrhymatum Solem, 1973
2. H/D ratio of adults usually much more than 0.575, spire
markedly elevated; ribs heavy and wide 3
H/D ratio of adults usually substantially less than 0.575, spire
flat or barely emergent; ribs fine and numerous, very widely
spaced, or greatly reduced on part of last whorl 5
3. Mean diameter less than 3.0 mm.; ribs greatly reduced or absent
on most of body whorl; Tonga 4
Mean diameter more than 3.55 mm.; ribs normally present on
entire body whorl; Samoa.
Thaumatodon hystricelloides (Mousson, 1865)
4. Mean D/U ratio about 10.0; Eua Island.
Thaumatodon euaensis, new species
Mean D/U ratio about 4.00; Vavau Island.
Thaumatodon vavauensis, new species
5. Mean D/U ratio more than 3.70, umbilical margin not
shouldered (fig. 193c); major ribs distinct but numerous (85-
160); Ellice and Cook Islands 6
Mean D/U ratio less than 3.45. umbilical margins weakly to
strongly shouldered (fig. 193f); major ribs very numerous or
reduced to irregularity; Lau Archipelago, Fiji 7
6. Mean diameter about 2.65 mm.; whorls 47/8-5'/2; beading on
apertural barriers restricted to posterior portion, never any
hooked denticles on teeth; Ellice Islands.
Thaumatodon decemplicata (Mousson, 1873)
Mean diameter about 3.40 mm.; whorls 6Vi-6%; apertural
barriers almost always with macroscopic spines or hooked
denticles over entire length (fig. 192d-e); Rarotonga, Cook
Islands Thaumatodon multilamellata (Garrett, 1872)
7. Adult with more than 4'/2 whorls; major parietal barriers 3;
sculpture greatly reduced and irregular; mean diameter more
than 2.8mm 8
Adult with less than 4'/z whorls; major parietal barriers 4,
although 2nd greatly reduced in prominence; ribbing fine, but
regular, 180 - 210 ribs on body whorl; mean diameter about
2.15 mm Thaumatodon laddi, new species
8. Body whorl with prominent spiral cording (fig. 196e).
Thaumatodon corrugata, new species
Body whorl without prominent spiral cording.
Thaumatodon subdaedalea (Mousson, 1870)
GROUP OF Thaumatodon decemplicata
Thaumatodon multilamellata (Garrett, 1872).
Figure 192a-e.
Pitys multilamellata Garrett, 1872, Amer. Jour. Conchol., 7, (4), p.
320, pi. 19, fig. 25 - Rarotonga, Cook Islands; Garrett, 1881,
Jour. Acad. Nat. Sci., Philadelphia. 8, (4), p. 389.
Patula multilamellata (Garrett), Schmeltz, 1874, Cat. Mus.
Godeffroy, 5, p. 94.
Helix (Pitys) multilamellata (Garrett), Pfeiffer, 1876, Monog. helic.
viv., 7, p. 569.
Helix (Endodonta) multilamellata (Garrett), Tryon, 1887, Man.
Conchol., (2), 3, pp. 63-64, pi. 12, figs. 14-16.
Endodonta (Thaumatodon) multilamellata (Garrett), Pilsbry,
1893, op. cit., (2), 9, p. 26, pi. 4, figs. 35-38.
Diagnosis. — Shell larger than average, diameter 3.09-3.75 mm.
(mean 3.39 mm.), with 6'/i-6% quite tightly coiled whorls. Apex flat,
spire slightly and evenly elevated, last whorl descending slightly
more rapidly, H/D ratio 0.496-0.562 (mean 0.533). Umbilicus U-
shaped. regularly decoiling, contained 3.48-4.54 times (mean 3.99) in
the diameter. Sculpture of fine, moderately closely spaced, almost
vertical radial ribs, 98-160 (mean 122.0) on the body whorl, whose
interstices are 2-3 times their width. Microsculpture of fine radial
riblets, three to five between each pair of major ribs, crossed by
extremely fine and crowded spiral riblets. Sutures impressed, whorls
strongly rounded above, compressed laterally, with evenly rounded
basal margin. Aperture sub-ovate, compressed laterally, inclined less
than 5° from shell axis. Parietal barriers 4, extending posteriorly less
than one-quarter whorl, sometimes (11 per cent) with an accessory
threadlike trace between 2nd and 3rd parietals: upper parietal
moderately high, expanded above with unusually sharp, rather
widely spaced crystalline barbs, with gradual descension over
anterior third; 2nd, 3rd and 4th parietals slightly reduced in height,
moderately expanded above on posterior three-quarters, with gradual
anterior descension. Columellar barriers 2, rarely 1, lying parallel
or barely slanted down from plane of coiling; upper, when present,
narrow, weakly expanded above with sharp anterior descension
midway across columellar callus; lower slightly higher, thicker,
moderately expanded above, with more gradual anterior descension
midway across callus. Palatal barriers 5 (67 per cent) or 6 (33 per
cent), extending posteriorly to line of vision, moderately recessed
within aperture, equal in height, with gradual anterior descension,
relatively low, surmounted either by recurved hooked structures (fig.
192d) or sharp barbs (fig. 192e).
In size and general appearance, Thaumatodon
multilamellata is quite similar to Mautodontha con-
sobrina from the Society Islands. The latter, however,
has a fatter body whorl, much larger umbilicus and
smaller, shorter, palatal barriers. The development of
1 mm
GT
GG
DG
FIG. 191. Anatomy of Thaumatodon: a-c, Thaumatodon hystricelloides. Upolu, Samoa. FMNH 153423. a, genitalia, b, detail of uterine
structure, c, penial complex; d-f, Thaumatodon decemplicata. Vaitupu, Ellice Islands. BPBM 189680. d, terminal genitalia, e, interior of
penis, /, insertion of penial retractor. Scale lines equal 1 mm.
449
450
SOLEM: ENDODONTOID LAND SNAILS
FIG. 192. a-e, Thaumatodon multilamellata (Garrett). Rarotonga, Cook Islands; a-b, paratype. BPBM 2316; e, FMNH 46268. Scale line
equals 1 mm. d-e greatly enlarged (a-d, SG; e, MM).
distinct high hooks on the palatals is unique to T.
multilamellata, and immediately separates it from all
other endodontids. The much larger and much more
elevated Tongan and Samoan species have heavy
beading on the barriers, many accessory traces, and
fewer, coarser ribs. T. decemplicata is nearly identical
in shape and sculpture, but is much smaller and has
shorter barriers with prominent beading on the
parietals. All other Thaumatodon have only 4 major
palatals.
Description. — Shell relatively large, with 6% tightly coiled
whorls. Apex and early whorls of spire flatly coiled, last 3 whorls
descending moderately rapidly, H/D ratio 0.496. Apical whorls l'/2,
sculpture mostly eroded with only traces of radial ribbing persisting
in the sutures. Postnuclear whorls with prominent, V-shaped,
vertically sinuated radial ribs, 124 on the body whorl, whose
interstices are about twice their width. Microsculpture of relatively
strong radial riblets, three to five between each pair of major ribs,
with barely visible traces of very fine and crowded spiral riblets.
Sutures deep, whorls strongly rounded above, somewhat compressed
laterally with evenly rounded outer margin. Color light yellow horn
with broad, regularly spaced reddish flammulations that become
narrow on shell base. Umbilicus narrowly U-shaped, slightly and
regularly decoiling, contained 4.11 times in the diameter. Apical
sculpture of very fine, crowded radial riblets clearly visible in
umbilicus. Aperture sub-ovate, compressed laterally, with evenly
rounded outer margin, inclined less than 5° from shell axis. Parietal
barriers, 4, extending almost one-quarter whorl: 1st parietal high,
narrow, bladelike, with moderately sharp anterior descension; 2nd,
3rd, and 4th parietals differing primarily in more gradual anterior
SYSTEMATIC REVIEW
451
descension and extending slightly further anteriorly. Columellar
barriers 2, moderately recessed within aperture: upper columellar
thin, bladelike, with gradual anterior descension; lower columellar
higher, thickened basally with sharp anterior descension. Palatal
barriers 5, high, bladelike, extending posteriorly three-sixteenths of a
whorl, with four to six crystalline hooks on upper edge which point
toward the aperture; palatals gradually less recessed within aperture
from bottom to top, equal in size and prominence. Height of
lectotype 1.81 mm., diameter 3.75 mm.
Lectotype. — Cook Islands: Rarotonga. Collected
by Andrew Garrett. ANSP 47792.
Range. — Rarotonga, Cook Islands.
Paratypes. - BPBM 2316, ANSP 290108.
Material. — Cook Islands: Rarotonga (18 speci-
mens, AMS, Zurich, SMF 158296, FMNH 46268,
BPBM 2316, ANSP 47792, ANSP 290108).
Remarks. — While most species of endodontids
have the apertural barriers expanded above and
minutely serrated with crystalline extensions (fig. 37a-
c), Thaumatodon multilamellata is the only known
species which has developed actual hooks that point
toward the aperture or high pointed barbs. Somewhat
similar hooks are also known in the totally unrelated
Strobilopsidae from the holarctic region (see Pilsbry,
1931, pi. 11, fig. 7 of Enteroplax boholensis) and New
Zealand taxa (Solem, 1970b, pi. 60).
T. multilamellata was reported by Garrett (1881,
p. 389) as "Not uncommon, and obtained in two
separate valleys on Rarotonga." During two trips to
Rarotonga in 1964 and 1965, Mr. Laurie Price was
unable to locate any of the Endodontidae described or
reported by Garrett, except for the supralittoral
Libera fratercula. T. multilamellata probably is ex-
tinct.
Available material, 18 specimens, suggested that
there was subspecific differentiation between the two
sampled colonies. Two specimens (FMNH 46268) had
only 1 columellar barrier and quite minute, nearly
vertical barbs on the palatal barriers (fig. 192e). All
other specimens had the large hooks (fig. 192d), and 2
columellar barriers found in the type. Sometimes (11
per cent) an accessory parietal lamellar trace was
present between the 2nd and 3rd parietals, and 33 per
cent of the specimens had a 6th palatal.
In the absence of any anatomical evidence,
association of this species with the other Thaumato-
don is based upon a set of three specimens (Zurich),
one of which has the barriers beaded instead of being
"hooked." Possibly, only a single genetic mutation is
involved in the transition from "beaded" to "hooked."
Thaumatodon decemplicata (Mousson, 1873).
Figures 191d-f; 193a-c.
Pithys decemplicata Mousson, 1873, Jour, de Conchyl., 21, p. 105
— Nukufetau and Vaitupu, Ellice Islands.
Helix (Pithys) decemplicata (Mousson), Pfeiffer, 1876, Monog.
helic. viv., 7, p. 259.
Helix (Endodonta) decemplicata (Mousson), Tryon, 1887, Man.
Conchol., (2), 3, p. 63.
Endodonta (Thaumatodon) decemplicata (Mousson), Pilsbry,
1893, op. cit., (2), 9, p. 26.
Diagnosis. — Shell smaller than average, diameter 2.44-2.76 mm.
(mean 2.64 mm.), with 47/s-5'/2 relatively tightly coiled whorls. Apex
and spire slightly elevated, rounded above, last whorl descending
much more rapidly, H/D ratio 0.513-0.562 (mean 0.533). Umbilicus
V-shaped, of average width, regularly decoiling, contained 3.61-4.35
times (mean 3.92) in the diameter. Sculpture of closely set,
protractively sinuated radial ribs, 85-110 (mean 94.1) on the body
whorl, whose interstices are about twice their width. Microsculpture
of fine radial riblets, three to five between each pair of major ribs,
crossed by extremely fine and crowded spiral riblets, with a
secondary spiral sculpture of narrow, rather widely spaced spiral
cords. Sutures impressed, whorls strongly rounded above, slightly
compressed laterally, with evenly rounded basal margin. Aperture
subcircular, compressed laterally, inclined about 5° from shell axis.
Parietal barriers 4, extending posteriorly less than one-quarter whorl:
upper a high, thin blade, expanded above posteriorly, two or three,
weak, widely spaced beads on posterior half, with gradual descension
over anterior third; 2nd parietal slightly lower, with two larger beads
on posterior three-eighths, anterior half a raised threadlike ridge
terminating beyond edge of upper parietal; 3rd parietal slightly
higher than 2nd, identical in shape, beading slightly larger and with
anterior portion more elevated; 4th parietal greatly reduced in height
posteriorly, with two or three very indistinct beads, anterior
threadlike portion terminating slightly behind edge of 3rd parietal.
Columellar barrier a low lamella, slightly twisted downwards from
plane of coiling, with rather sharp descension almost to lip edge.
Palatal barriers 5, extending posteriorly less than three-sixteenths of
a whorl: lower moderately elevated, with three weak beads on
posterior half, with sharp anterior descension to lip edge; 2nd slightly
reduced in height, 3rd equal in height to 1st, 4th slightly lower than
2nd, all with same beading and with progressively more gradual
anterior descension; 5th palatal supraperipheral, greatly reduced in
height and length, beading reduced to three narrow, only weakly
bulbous irregularities, moderately recessed within aperture.
Thaumatodon decemplicata is characterized by its
small size, narrow ribbing, restriction of the simple
beading to the posterior portion of the barriers, single
columellar and 5 palatals. The much larger T.
multilamellata (mean diameter 3.39 mm.) has
"hooked" projections on the entire length of the
palatal barriers and more whorls (6'/4-63/4), but is
essentially identical in shape and ribbing. The Tongan
and Samoan species are much higher with very strong
ribbing, although similar in size, while the subdae-
dalea complex has reduced sculpture and only 3 or 4
palatals.
Description. — Shell of less than average size, with a little more
than 5'/6 tightly coiled whorls. Apex flat, whorls of spire descending
gradually, H/D ratio 0.497. Embryonic whorls 1%, sculpture of fine
crowded radial riblets, crossed by finer slightly more widely spaced
spiral riblets. Postnuclear whorls with prominent, rounded, crowded,
somewhat protractively sinuated radial ribs, 93 on the body whorl,
whose interstices are usually less than twice their width. Micro-
sculpture of prominent, rather widely spaced radial riblets, crossed
by extremely fine and crowded spiral riblets with a secondary
sculpture of strong, widely spaced spiral cording. Sutures moderately
deep, whorls strongly rounded above, slightly compressed laterally
with evenly rounded outer and basal margins. Umbilicus V-shaped,
regularly decoiling, contained 3.66 times in the diameter. Color light
reddish yellow-orange with narrow, zigzag, radial reddish markings,
more prominent on body whorl, very faint above. Aperture ovate,
with evenly rounded margins, inclined about 5° from shell axis.
Parietal barriers 4, extending slightly less than one-quarter whorl:
a
FIG. 193. a-c, Thaumatodon decemplicata (Mousson). Nukufetau, Ellice Islands. Paratype. FMNH 116990; d-f, Thaumatodon laddi, new
species. Station 27, Wangava Island, Lau Archipelago, Fiji. Holotype. BPBM 166966. Scale lines equal 1 mm. (MM).
452
SYSTEMATIC REVIEW
453
1st and 3rd moderately high with two strong posterior beads, 1st
descending rather sharply and 3rd more gradually; 2nd and 4th
reduced in prominence with anterior half threadlike, weakly
expanded and beaded posteriorly. Columella with single, ridgelike
barrier located near basal margin and slanting slightly downwards.
Palatal barriers 5: lower 4 extending three-sixteenths of a whorl,
moderately elevated, approximately co-equal and reaching lip
margin, each with 2 beads above; upper palatal reduced in
prominence, low, ridgelike, slightly supraperipheral in position. Basal
and palatal lips with moderately heavy translucent callus. Height of
lectotype 1.32 mm., diameter 2.65 mm.
Lectotype. — Ellice Islands: Nukufetau. Collected
by Dr. E. Graeffe. Zurich 502969.
Range. — Ellice Islands: Nukufetau and Vaitupu
Island.
Paratypes. - Nukufetau (Zurich 502969, FMNH
116990); Vaitupu (Zurich 502970, FMNH 116987).
Material. — Ellice Islands (5 specimens, FMNH
117004): Vaitupu (11 specimens, BPBM 189680);
Nukufetau (19 specimens, BPBM 189673, FMNH
118394).
Remarks. — This species is known only from the
original collections of Mousson on Nukufetau and
Vaitupu, four specimens collected in rotting wood on
Vaitupu by L. Isaacs in May, 1941 (BPBM 189680),
and seven specimens collected by Isaacs on Nukufetau
during the same period (BPBM 189673). Material from
Vaitupu and Nukufetau do not differ significantly
(table CX), nor do specimens from Graeffe 's collecting
in the 1860's and Isaacs' material taken in 1941. With
9-10 df, "t" was only 0.54-1.11 for all parameters.
Beading on the parietal barriers is restricted to the
posterior portion, although present over the entire
length on the lower palatals. Compared with T.
multilamellata and T. hystricelloides, the barriers are
much shorter and smaller.
The similarity in sculpture, shape, and form to T.
multilamellata is quite marked, the major differences
being in shell size, and the length and sculpture of the
apertural barriers. The very small T. laddi from
Wangava, Fiji, has a more open umbilicus with slight
shouldering and very fine, crowded radial sculpture.
Description of soft parts. - Only the anterior parts of one
animal were available. Terminal genitalia (fig. 191e, f) as follows:
Vas deferens (VD) slender to penioviducal angle, thickened to point
about three-quarters of way up penis where it enters a weakly
expanded epiphallus (E). Latter not demarcated from penis proper
(P), but probably functionally set off by insertion of penial retractor
(PR, fig. 191d). Penis about 0.5 mm. long, expanded above, strongly
tapered for anterior third to junction with spermatheca and atrium.
Penis internally (fig. 191e) with two pilasters (PP), one greatly
enlarged, both continuing to epiphallic head apically. the smaller
fading out on lower portion of penis wall. Opening from vas deferens
to epiphallus of same type found in Aaadonta (fig. 199d).
Spermathecal stalk (S) same diameter as vas deferens. entering penis
base just above junction of latter with atrium. Free oviduct (UV)
almost equal in diameter to penis, narrowing abruptly just before
joining penis to form atrium (Y). Length of latter not observed.
Radula lost in processing.
(Based on BPBM 189680.)
GROUP OF Thaumatodon hystricelloides
Thaumatodon hystricelloides (Mousson, 1865).
Figures 191a-c; 194d-e; 197d-f; 208e.
Patula (Endodonta) hystricelloides Mousson, 1865, Jour, de
Conchyl., 13, pp. 169-170, 431, pi. 14, fig. 6 - Upolu, Samoa;
Mousson, 1869, op. cit., 17, pp. 331-332.
Helix hystricelloides (Mousson), Pfeiffer, 1868, Monog. helic. viv.,
5, p. 221.
Pifys hystricelloides (Mousson), Pease, 1871, Proc. Zool. Soc.
London, 1871, p. 474; Garrett, 1887, Proc. Acad. Nat. Sci.
Philadelphia, 1887, p. 1:50.
Helix (Endodonta) hystricelloides (Mousson), Tryon, 1887, Man.
Conchol., (2), 3, p. 65, pi. 12, fig. 30.
Endodonta (Thaumatodon) hystricelloides (Mousson), Pilsbry,
1893, op. cit., (2), 9, p. 27.
Partula (sic) hystricelloides Mousson, Fischer- Piette, 1950, Jour.
de Conchyl., 90, (2), p. 66 — location of figured specimens.
Diagnosis. — Shell large, diameter 3.42-4.11 mm. (mean 3.70
mm.), with 5'4-534 moderately tightly coiled whorls. Apex somewhat
flattened, spire strongly elevated, shape globose, last whorl descend-
ing slightly more rapidly, H/D ratio 0.576-0.752 (mean 0.663).
Umbilicus narrowly U-shaped, regularly decoiling, contained 3.89-
7.60 times (mean 5.11 times) in the diameter. Postnuclear sculpture
of strong, protractively sinuated radial ribs, 59-93 (mean 70.9) on the
body whorl, whose interstices are slightly less than twice their width.
Microsculpture of fine radial riblets, five to eight between each oair
of major ribs, crossed by much finer and more crowded spiral riblets.
Sutures deep, whorls strongly rounded above and on basal margin,
slightly compressed laterally with evenly rounded outer margin.
Aperture subcircular. compressed laterally, inclined about 5-10° from
shell axis. Parietal barriers 4, extending posteriorly less than one-
quarter whorl, with two accessory traces: upper a high, thin blade,
expanded above with three to four large beads that twist downward
and backward and are covered with minute barbs (fig. 195d), anterior
three-eighths simple with sharp anterior descension; 2nd greatly-
reduced in height, a low lamellar blade, with two to three simple
elongated beads (fig. 195d) on posterior two-thirds, anteriorly with
more gradual descension to point just beyond end of upper parietal;
3rd slightly lower than 1st, strongly expanded and beaded above on
posterior two-thirds, with rather gradual anterior descension; 4th a
very low, threadlike trace, weakly elevated and beaded above.
Accessory traces located above upper and below 4th palatal, both
small threadlike ridges, upper only slightly, lower moderately
recessed within aperture. Columellar barriers 1 or 2, upper, when
present, a low threadlike trace, weakly elevated and beaded above
posteriorly beyond callus; lower high and bladelike. expanded and
beaded above posteriorly, lying parallel to plane of coiling, with
sharp anterior descension to lip edge. Palatal barriers 4, extending
posteriorly less than three-sixteenths of a whorl, with five to eleven
accessory traces: lower at baso-columellar margin, very high,
strongly expanded and beaded above posteriorly, with abrupt
descension to lip edge; 2nd and 3rd equal to 1st in height and
beading, with progressively more gradual anterior descension; 4th
supraperipheral, scarcely larger than adjoining traces, a short, thin,
low ridge with two very large beads above, with very gradual
anterior descension. Accessory traces normally two or three between
1st and 2nd; two between 2nd and 3rd; two between 3rd and 4th;
two to four above 4th palatal. Larger traces may show small beads
above or consist just of small beads on the palatal wall with the
lamellar blade absent.
The large size, markedly elevated spire, coarse ribs
that normally continue to the aperture, and huge
beaded barriers characterize Thaumatodon hys-
tricelloides. Of the Tongan species, T. vavauensis is
much smaller, has 3 major parietals, although very
similar in shape and sculpture, while T. euaensis has a
much narrower umbilicus, many more parietal traces,
O
Q
O
EH
D
O
00
co'
o „•
CO
"S.
CM
CN CO
^f
LO^
rH
10
N
1S3
3
Q
-^
X
<N
CO
CO CO
*-l CM
O CO
CO i
co CO
O CO
EH
I— I
O
(N
CO
CN
<N „
o m
CO
CM'
co i
O CO
o'
o3<a
CO
CO CO
CO I
O rH
• 10
CO
10
O rH
|«
CO
co'
10
CM'
X
O
o rt
8
<=> CO
CN co
«fr to" o -a P co o" i-T o ,3 _2 05 r-T CN PC-CO co
°°" t ^
2
rt
CO ^
I-H tr~
CO CO
-OOOC .^H tr-^-s ^-^
•^•^con) fl co3 3
OO C~ "Ti ~^ "*> 0i cfl (^ "i
CMCDC043 C- CO" % £
•^tCOC- O ri COt-Ht-H -^OOCO
c^^co DH coeval cnaio
CO C~- LO *"") t-^" O^ CT) GJ CT3 C^ O CO
OCOr-) t3, *=i- C~ t- C- C^C-CO CO
i— i iO ;u
gg
CO CO
nj
<U 3
<» iH %
._. — U
CQ CQ *o_
o-o- c
CQ CQ C
222! « si 11 1
CQCQCQ" CQ^ !i-3aJ
Q-Q-CL^ 3 O-Z ^CZ, 0
CQCQCCltti- N CQ^- tsJ G* -S
222 I I" |
CQ CQ CQ "O -n
O- Q- Q- >^ ai
CQ CQ CQ M « cfl
1— 1 1— 1 T— 1
222 «
CQ CQ CQ ti
Q- Q- CL «r
CQ CQ CQ W
i-H i-H T-( t-H
222 2
CQ CQ CQ CQ
O- CL Q- Q-,
CQ CQ CQ ,_H CQ
i-H i-H
2 2
mm J3
Q, D-, g
ac
y.
1 a
(U
U
to
s
£
TD
s |
z E
1)
T3
>
a
O
U
^
-H 3
« U
454
SYSTEMATIC REVIEW
455
and is much smaller. All other Thaumatodon have
much finer sculpture and are much more depressed.
Description. — Shell large, with 5%+ tightly coiled whorls. Spire
distinctly elevated, apex barely protruding, whorls of spire descend-
ing progressively more rapidly, H/D ratio 0.619. Embryonic whorls
l'/2, sculpture mostly eroded with only faint traces of radial ribbing
remaining. Postnuclear whorls with very prominent, rounded, slightly
protractively sinuated radial ribs, 79 on the body whorl, whose
interstices are 2-3 times their width. Microsculpture of moderately
strong, crowded radial riblets, five to eight between each pair of
major ribs, with extremely fine, barely visible spiral riblets. Sutures
moderately impressed, whorls slightly shouldered above, somewhat
flattened laterally with evenly rounded basal margin. Color light
yellowish-brown with occasional darker reddish flammulations
visible. Umbilicus narrowly open, U-shaped, not decoiling, contained
3.89 times in the diameter. Aperture ovate, compressed laterally,
inclined about 5° from the shell axis. Parietal barriers 4, extending
slightly less than one-quarter whorl, with two accessory traces: upper
parietal high, bladelike with laterally slanting beads above
posteriorly and sharp anterior descension; 2nd parietal much lower,
long, bladelike, with three irregular beads above; 3rd parietal equal
in height to the 1st, broadly expanded above with four irregular
beads visible; 4th parietal low, threadlike, relatively broad above
with faint, irregular, posterior beading. Parietal traces located
between upper parietal and upper parietal margin, and between
lower parietal and columellar margin: upper, long, threadlike, very
narrow; lower short, threadlike, deeply recessed within aperture.
Columellar barriers 2: upper a low, recessed, threadlike trace; lower a
high, threadlike ridge, parallel to plane of coiling and reaching lip
edge. Major palatal barriers 4, with twelve accessory traces: lower
palatal at baso-columellar margin, very high, crescentic, with
broadly expanded posterior beading and sharp descension to lip edge;
2nd palatal slightly lower, broadly rounded above with large
posterior beads; 3rd palatal slightly subperipheral, very high, with
two broad posterior beads and gradual anterior descension, moder-
ately recessed within aperture; upper major palatal low, threadlike,
faintly beaded above, lying opposite upper parietal, almost per-
ipheral in position. All palatal barriers extending a little more than
one-eighth whorl. Palatal traces located between lower columellar
and 1st palatal, 1st palatal and 2nd palatal, two between 2nd and
3rd palatals, three between 3rd and 4th palatals, and four between
4th palatal and upper palatal margin. All traces narrow, threadlike,
occasionally faintly beaded above. Height of lectotype 2.14 mm.,
diameter 3.40 mm.
Lectotype. — Samoa: Upolu. Collected by E.
Graeffe. Zurich 502959.
Range. — Formerly over much of Upolu, now
restricted to upland forest areas, probably in most
areas only over 2,600 ft. elevation.
Paratypes. - Zurich 502958, FMNH 116984 (43
specimens).
Material. — Samoa (17 specimens, FMNH 46420,
BPBM 159, BPBM 106240, BPBM 115370, BPBM
167431, SMF 165383); Upolu (17 specimens, FMNH
91112, FMNH 116989, FMNH 116694, FMNH 117266,
SMF 165382, Sydney, Zurich 502959, Paris, Brussels,
Brit. Mus.); Lake Lanuto'o, ridge at 2,380 ft. elevation
(1 specimen, BPBM 186395); Mt. Siga'ele at 2,675 ft.
elevation, Station 24 (5 specimens, FMNH 153618);
below crater rim of Lake Lanuto'o at 2,500 ft.
elevation, Station 19 (90 specimens, FMNH 153038,
FMNH 153061, FMNH 153130-1, FMNH 153423,
FMNH 153542); Tapatapao - Lake Lanuto'o trail,
Station 20, at 1,800 ft. elevation (2 specimens, FMNH
153412).
Remarks. - Cited by Garrett (1887b, p. 131) as
"Not uncommon under rotten wood and beneath
decaying leaves," in 1965 T. hystricelloides was only
found below the crater rim of Lake Lanuto'o at 2,500
ft., on the trail up to the lake at 1,800 ft. elevation and
near the summit of Mt. Siga'ele at 2,675 ft. elevation.
Although numerous stations at lower elevations were
visited, no trace of this species was found except in the
upland forest remnants. At the one station it was
quite common, but elsewhere seems to have become
extinct. The observed habitat was under dead Pan-
danus leaves near Lake Lanuto'o and under rotting
leaves on Mt. Siga'ele.
Previous material was taken by Graeffe (1860's),
Garrett (1870's), and a single specimen by E. C.
Zimmerman (1940). The Graeffe and Garrett speci-
mens are widely, although sparsely, represented in
collections throughout the world. Mousson's collection
(Zurich) contained some 39 examples received from
Graeffe in 1864, 1868, and 1872. Unfortunately, these
specimens had been mixed together. The single
example collected by Zimmerman in 1940 near Lake
Lanuto'o (BPBM 186395) was the most elevated
specimen examined (H/D ratio 0.752). Specimens
collected by Solem and Price in 1965 did not differ in
general appearance or barriers from those in older
collections.
Apertural barrier variation consisted primarily in
the number of palatal traces. As few as four, as many
as eleven were observed, with eight to ten the most
prevalent numbers. No differences between sets were
observed.
Mousson's record of this species from Vavau,
Tonga (Mousson, 1871, pp. 10-11) was based on T.
vavauensis, new species.
Description of soft parts. — Foot slender, length about equal to
shell diameter, truncated anteriorly, with head projecting in front of
foot. Tail variable, rounded to slightly tapered behind. Sole
undivided, smooth. Pedal grooves rather high on foot, suprapedal
much weaker, both united above tail. No caudal horn or middorsal
groove visible. Slime network very faint, no marked pattern.
Ommatophores long, eyespots very small, black. Retractor muscles
brown for first part of length. Gonopore a large slit directly behind
right rhinophore, almost directly below right ommatophore.
Body color in life and preservative faint yellow-white.
Mantle collar (MC) with thickened, protruded edge, no distinct
lappets developed, but a very large triangular, glandular extension
onto pallial roof. Pneumostome in parietal-palatal angle, without
any distinct mantle lobes. Anus (A) opening just inside edge of
mantle collar, a distinct groove continuing to outer edge of collar.
Pallial region extending apically one-half whorl, of normal
width, about 4.8 mm. long. Lung roof with bands of white granules
flanking principal pulmonary vein, continuing apically along ureter
and kidney. Kidney (K) about 1.8 mm. long, 1.7 times length of
heart, tapering anteriorly, rounded basally, with small hooked
portion abutting hindgut. and intestinal loop reaching base. Ureter
(KD) starting at apex of kidney, following lower margin and opening
just anterior of pericardia! kidney termination, no secondary ureter
456
SOLEM: ENDODONTOID LAND SNAILS
present. Heart (H) nearly parallel to hindgut, rather slender and
elongated. Principal pulmonary vein (HV) slender, angling towards
pneumostome, unbranched until just before invasion of shell glands
onto lung roof, then heavily invading area. Hindgut (HG) starting at
reflexion of intestine 1.65 mm. above kidney base, passing normally
forward to anus.
Ovotestis (fig. 191a, G) extending two-thirds whorl apically
above stomach, composed of palmately clavate alveoli along a simple
collecting tubule. Hermaphroditic duct (GD) slender at first,
expanded into a very short contorted section, then grossly expanded
to a long straight tube that turns and narrows slightly before
entering carrefour. Albumen gland (GG) typical. Talon (GT) a
fingerlike tube lateral to junction of hermaphroditic duct and
carrefour. Prostate (DG) of two rows large acini opening into a
separate tube, slightly shorter than uterus. Uterus (fig. 191a, b, UT)
with a peculiar glandular head (UTi), a slender section (UT2),
typically expanded lower chamber (UT.i), and then a terminal, more
glandular portion (UT4) before narrowing to enter free oviduct.
Vas deferens (VD) a continuation of prostate duct, loosely
bound to penioviducal angle, entering through a lip arrangement into
epiphallus. Epiphallus (E) less than one-third length of penis,
opening of vas deferens as in Aaadonta (fig. 199d), with two pilasters
continuing into penis. Penial retractor (PR) originating on dia-
phragm, inserting on penis-epiphallus junction. Penis (fig. 191c, P)
enervated from right cerebral ganglion, about 1.5 mm. long,
moderately bulbous on lower half, internally with weak crenulated
pilasters continuing from epiphallus. then each bifurcating medially
in penis, one uniting again just before atrium, the other pair
gradually diminishing. Pattern very similar to that seen in Aaadonta
(fig. 199d). Atrium (Y) short, not strongly sculptured.
Free oviduct (UV) narrow, internally with longitudinal pilasters,
rather sharply delineated from thin-walled uterus. Spermatheca (S)
with oval expanded head lying partly next to head of prostate and
uterus, partly next to albumen gland base. Vagina absent.
Free muscle system typical of subfamily. Right ommatophoral
retractor passing through penioviducal angle. Right rhinophoral
retractor passing outside penioviducal angle, uniting with right
ommatophoral retractor about two-thirds of way to point where
tentacular retractors unite laterally with tail fan anterior to point
where buccal retractors join tail fan to form columellar muscle.
Buccal mass normal, hump shaped. Buccal retractors split, two
fine lateral bands uniting much posterior of main band junction.
Esophagus arising just behind midpoint of stomach, esophagus
opening into stomach just above apex of pallia! cavity. Latter
extends one-half whorl apically. before reflexing just short of
ovotestis. Intestine with normal pattern of looping, lower loop
abutting kidney base as in Endodonta fricki. Hindgut starting 1.5
mm. above apex of pallial cavity, following parietal-palatal angle
forward to anus.
Digestive glands extending 1'4 whorls past ovotestis to apex of
soft parts, in narrow strip along stomach, expanding in region of
intestinal loops, touching apical wall of pallial cavity. Salivary
glands uniting above esophagus for posterior half of length, with
several digitiform extensions pointing downwards.
Jaw very delicate, composed of many elongated, separate but
overlapping plates, weakly attached by a membrane.
Radula with more than 105 rows, central tooth about 8ju wide
and lOfi long, laterals 7 or 8. with 11-12 marginals.
(Based on five adult specimens, FMNH 153423.)
Thaumatodon euaensis, new species. Figures
194a-c; 195.
Diagnosis. — Shell small, diameter 2.35-3.03 mm. (mean 2.54
mm.), with 4%-55/s normally coiled whorls. Apex and spire rather
strongly and evenly elevated, last whorl descending only slightly
more rapidly, H/D ratio 0.632-0.713 (mean 0.666). Umbilicus very
narrow, U-shaped, not decoiling, contained 7.22-13.3 times (mean
9.83) in the diameter. Postnuclear whorls with high, broadly rounded,
protractively sinuated radial ribs, that fade out on last parts of body
whorl, spaced so that there would be between 45 and 65 ribs on the
body whorl if not absent on last parts. Microsculpture of fine radial
riblets, five to eight between each pair of major ribs, crossed by
extremely fine and crowded spiral riblets. Sutures relatively shallow,
whorls strongly rounded above and on basal margin, somewhat
compressed laterally on lower palatal margin. Aperture subovate,
somewhat compressed laterally, inclined about 15° from shell axis.
Parietal barriers 3 (38.1 per cent) or 4 (61.9 per cent), 2nd greatly
reduced in prominence or absent, extending posteriorly slightly more
than three-sixteenths of a whorl, with eight to fourteen accessory
traces: upper very high, slender, expanded and very weakly beaded
on posterior two-thirds, with sharp anterior descension; 2nd, when
not reduced to a threadlike trace, about one-third to one-half height
of 1st parietal, expanded above with two distinct beads posteriorly,
anterior half threadlike and extending to anterior end of upper
parietal; 3rd parietal slightly lower at first, more prominently
expanded and beaded above on posterior half, with anterior third a
threadlike trace; 4th parietal almost equal in height to 3rd, usually
with more gradual anterior descension and greater elevation of
anterior portion. Parietal traces variable in number and position,
generally two above upper parietal; one between 1st and 2nd; one
between 2nd and 3rd; three between 3rd and 4th parietals; and three
or four between 4th parietal and parietal-columellar margin.
Columellar barriers 2, often (19 per cent) with slender trace present
between upper columellar and columellar-parietal margin; upper
columellar moderately elevated, bladelike, lying parallel to plane of
coiling, somewhat expanded and serrated above posterior to apex of
columellar callus, with gradual anterior descension to lip edge; 2nd
columellar much higher, similar in position, with sharp anterior
descension almost to lip edge. Palatal barriers 4, extending
posteriorly more than one-eighth whorl, very large, generally with
three (40 per cent) or four (45 per cent) accessory traces; lower
palatal extremely high, slender, expanded and weakly but distinctly
beaded posteriorly with sharp anterior descension to lip edge; 2nd
and 3rd palatals equal in height, weakly beaded above, with
progressively more gradual anterior descension, also nearly reaching
lip edge; 4th palatal lying opposite upper parietal, greatly reduced in
height and length, very slender and weakly expanded above, with
abrupt anterior descension almost to lip margin. Accessory traces
located between 1st and 2nd, 2nd and 3rd, 3rd and 4th, and often (45
per cent) above 4th palatal. Occasionally there will be a second
accessory trace above the 4th palatal, or an accessory trace between
the lower columellar and 1st palatal.
Thaumatodon euaensis differs from the obviously
closely related Samoan species T. hystricelloides in
being much smaller, having a distinctly narrower
umbilicus, not having the 4th parietal barrier reduced
in size, always possessing 2 columellar barriers, having
the radial ribbing greatly reduced on the body whorl,
and in having the body whorl distinctly compressed
laterally. The other Tongan species, Thaumatodon
vavauensis, is a more depressed, widely umbilicated
shell, with very prominent radial ribbing on the body
whorl and only three to five accessory parietal traces.
Description. — Shell small, with 5'4 normally coiled whorls.
Apex and early spire moderately and almost evenly elevated, last
whorl descending slightly more rapidly, H/D ratio 0.671. Apical
whorls I'i, sculpture eroded. Postnuclear whorls with prominent,
broadly rounded, protractively sinuated radial ribs, that are
prominent until last two-thirds of body whorl, becoming in-
distinguishable on last quarter. If major ribbing continued normally,
there would be about 65 ribs on body whorl. Microsculpture of
extremely fine radial riblets, five to eight between each pair of major
ribs on early body whorl, crossed by extremely fine and crowded
spiral riblets. Suture shallow, whorls strongly rounded above and on
SYSTEMATIC REVIEW
457
a
anterior
posterior
a-c
anterior
posterior
FIG. 194. a-c, Thaumatodon euaensis, new species. Station T-22, Eua Island, Tonga. Holotype. FMNH 154784; d-e, Thaumatodon
hystricelloides (Mousson). d, parietal lamellae, e, 3rd and 4th palatal lamellae. Scale line equals 1 mm. Figures rf and e greatly enlarged. (MM).
umbilical margin, distinctly compressed laterally on lower palatal
margin, walls of umbilicus very strongly rounded. Color light yellow-
brown, with irregular, dark red flammulations, that become narrow
and strongly zigzagged on shell base, much more prominent on body
whorl than upper spire. Umbilicus quite narrow, distinctly wider at
apex than on last whorl, contained 9.11 times in the diameter.
Aperture subovate, distinctly compressed laterally, inclined about
15° from shell axis. Parietal barriers 4, extending posteriorly slightly
more than three-sixteenths of a whorl, with eleven accessory traces:
upper parietal quite high, slender, expanded above, weakly beaded on
posterior third, with very sharp anterior descension; 2nd parietal
about one-third height of 1st, weakly expanded and prominently
beaded above posteriorly, with gradual descension to anterior
threadlike five-eighths, that terminates opposite anterior end of
upper parietal; 3rd parietal two-thirds height of 1st, expanded above
and weakly beaded posteriorly, with gradual descension to anterior
threadlike third; 4th parietal equal in height to 3rd, with more
gradual descension anteriorly and much more elevated anterior
portion. Parietal traces located two above upper parietal, one
between 1st and 2nd, one between 2nd and 3rd, three between 3rd
and 4th, and four between 4th and columellar-parietal margin.
Upper parietal trace a slender, bladelike ridge, only slightly lower
458
SOLEM: ENDODONTOID LAND SNAILS
than 2nd parietal. Columellar barriers 2, lying parallel to plane of
coiling and reaching lip edge, with one threadlike superior trace: 1st
columellar moderately elevated, distinctly expanded and serrated
above behind columellar callus, with gradual anterior descension;
2nd columellar much higher, equally expanded and serrated above
posteriorly, with sharp anterior descension. Palatal barriers 4,
extending posteriorly more than one-eighth whorl, with three
accessory traces: 1st very high, expanded, weakly beaded above
posteriorly with very sharp anterior descension to lip edge; 2nd and
3rd equal in height to 1st, expanded and weakly beaded above
posteriorly, with progressively more gradual anterior descension; 4th
palatal lying opposite parietal, greatly reduced in height, weakly
expanded above, with sharp anterior descension almost to lip edge,
much shorter than 3rd parietal, with very gradual posterior
descension. Palatal traces located between 1st and 2nd, 2nd and 3rd,
and 3rd and 4th palatals, with the first accessory trace being much
lower and smaller than the upper two which are elevated V-shaped
ridges. Height of holotype 1.81 mm., diameter 2.70 mm.
Holotype. — Tonga Islands: Eua Island, Station T-
22, main ridge on east side at 1,000 ft. elevation in
heavy primary forest. Collected by Laurie Price on
January 31, 1966. FMNH 154784.
Range. — Eua Island, Tonga.
Paratypes. - FMNH 152377, BPBM
Material. - Tonga: Eua Island (Station T-22)
1,000 ft. elevation in heavy primary forest on east side
of main range (49 specimens, FMNH 152377, FMNH
154784).
Remarks. — Only 29 of the 49 examples collected
were adult, but no very young specimens were
obtained. The following ideas concerning umbilical
form were reached solely by careful inspection of shells
with adult umbilical form. It is evident that in very
young shells the umbilicus is distinctly wider than in
adults, and that umbilical narrowing takes the same
form as in the Marquesan Taipidon semimarsupialis,
by inward growth of the entire last whorl coiling. As a
result, the D/U ratio of Thaumatodon euaensis is
much, much greater than in any other species of
Thaumatodon (table CIX).
In general appearance, as well as in many details
of sculpture and structure, T. euaensis is an obvious,
close relative of the Samoan T. hystricelloides. The
most significant differences between the two are
covered above in the diagnosis. T. vavauensis, from
Vavau Island, Tonga, is somewhat similar in appear-
ance but differs by a number of features, including
strength of ribbing, width of umbilicus, height of spire,
number and relative size and length of apertural
barriers. Relationships to T. hystricelloides seem to be
much closer than those to T. vavauensis.
One specimen had a single, oblong egg resting just
inside the umbilicus. No other examples showed
indications of the umbilicus being used as a brood
chamber.
Description of soft parts. — Foot and tail retracted into pallial
cavity, when dissected all external features as in T. hystricelloides.
Body color faint yellow-white, no darker markings.
Mantle collar (MC) with thickened edge, no distinct lobes, large
glandular extensions onto pallial roof (ripped by palatal barriers
during dissection). Pneumostome typical. Anus (A) opening just
inside pneumostome in normal position.
Pallial region (fig. 195a) extending five-eighths whorl apically,
lung roof with broad bands of white granules flanking principal
pulmonary vein and kidney, extending to apex of soft parts. Kidney
(K) about 1.5 mm. long, bilobed, rectal arm almost half length of
pericardial, base of kidney lying above intestinal loop. Ureter (KD)
opening just anterior to rectal kidney arm termination. Heart (H)
more than half length of kidney, nearly parallel to hindgut. Principal
pulmonary vein (HV) slender, extending to glandular mantle lobe
intrusions, without obvious branching. Hindgut typical.
Ovotestis (G) composed of multiple clumps palmately clavate
alveoli along a simple collecting tubule, occupying full whorl above
stomach reflexion. Hermaphroditic duct (fig. 195c, GD) narrow at
first, becoming abruptly expanded, convoluted for a distance, then
becoming straight, finally reflexing into bulb of carrefour. Albumen
gland typical, surface dented by intestinal loops, an artifact
introduced by contraction. Talon (GT) with a short, stubby shaft
inserting on a bulbous carrefour. Prostate typical. Uterus extending
past end of prostate, with same structure found in T. hystricelloides.
Vas deferens (fig. 195b, VD) contorted in region of penioviducal
angle, an artifact of contraction. Epiphallus (E) about half length of
penis, structure as in Aaadonta constricta constricts (fig. 199d).
Penial retractor (PR) arising from diaphragm, inserting on
penis-epiphallus junction. Penis (P) about 1.0 mm. long (fig. 191a, P),
twisted from contraction in available material, internally with one
epiphallic pilaster fading out, other becoming grossly enlarged to
form a stimulatory pilaster submedially that extends nearly to
atrium. Atrium (Y) short.
Free oviduct (UV) with weak pilasters internally, much thicker-
walled than uterus. Spermatheca (S) with expanded head lying next
to base of albumen gland just at level of pallial cavity apex, slender
shaft inserting on penial side of penioviducal angle. Vagina absent.
Free muscle system typical. Right ommatophoral retractor
passing through penioviducal angle, tentacular retractors fuse
midway to union with tail fan and buccal retractor at columellar
insertion.
Digestive system as in T. hystricelloides.
Radula with more than 92 rows, central tooth about 8|U square,
laterals 7, marginals more than 8.
(Based on FMNH 152377, four adult specimens.)
Thaumatodon vavauensis, new species. Figure
196a-c.
Patula (Endodonta) hystricelloides Mousson, 1871 (not Mousson,
1865), Jour, de Conchyl., 19, pp. 10-11 - Vavao, Tonga Islands
(error in identification).
Diagnosis. — Shell small, diameter 2.40-3.14 mm. (mean 2.70
mm.), with 434-6 rather tightly coiled whorls. Apex and spire
moderately and evenly elevated, last whorl descending slightly more
rapidly, H/D ratio 0.568-0.634 (mean 0.610). Umbilicus open, U-
shaped, regularly decoiling, contained 3.37-4.44 times (mean 3.85) in
the diameter. Postnuclear sculpture of high, prominent, protractively
sinuated, broadly rounded radial ribs, 48-67 (mean 57.5) on the body
whorl, whose interstices are lVi-2 times their width. Microsculpture a
lattice of fine radial riblets, five to eight between each pair of major
ribs, crossed by extremely fine and crowded spiral riblets. Sutures
impressed, whorls strongly rounded above and one basal margin,
distinctly compressed laterally, with gently rounded outer margin.
Aperture subovate, distinctly compressed laterally, inclined about
15° from shell axis. Parietal barriers 3, extending posteriorly more
than three-sixteenths of a whorl, generally with four, sometimes only
two or three accessory traces: upper high, thin, weakly expanded
above, with five to six weak beads on top, gradually descending from
anterior quarter to just before termination when descension becomes
LP
SYSTEMATIC REVIEW
MC
459
PR
FIG. 195. Anatomy of Thaumatodon euaensis. Eua Island, Tonga. FMNH 152377: a, pallial region with mantle collar split by apertural
lamellae during dissection; b, penial complex; c, detail of apical genitalia. Scale lines equal 1 mm.
sharp; 2nd slightly lower in height, beading even weaker, restricted to
posterior half, with much more gradual anterior descension; 3rd
slightly reduced in height from 2nd, beading on posterior half only,
with gradual anterior descension to posterior of raised threadlike
anterior quarter. Accessory traces generally located above upper,
between each pair of major parietals, and between lower parietal and
parietal-columellar margin. Columellar wall with 1 or 2 (usually)
barriers: upper, when present, a small threadlike trace moderately to
deeply recessed within aperture; lower varying from a raised
threadlike ridge to moderately high barrier, lying parallel to plane of
coiling, with sharp anterior descension to lip edge, rarely reduced and
deeply recessed within aperture. Palatal barriers usually 3, sometimes
more, extending posteriorly about three-sixteenths of a whorl, with
two or three accessory traces: lower 2 high and bladelike, markedly
expanded and beaded above, with sharp anterior descension to lip
edge; 3rd supra peripheral in position, markedly reduced in height,
weakly beaded above, with more gradual anterior descension; 4th
palatal, when present, located between 1st and 2nd, equal in height;
accessory traces normally between 1st and 2nd, 2nd and 3rd palatals,
additional trace, when present, above upper palatal.
The greater H/D ratio, more projecting spire,
much narrower umbilicus, and normal presence of 4
major parietal barriers at once distinguish Thaumato-
don euaensis from the otherwise very similar T.
vavauensis. The latter has a widely open umbilicus,
rather depressed spire, and only 3 major parietals. The
Samoan T. hystricelloides is much larger, more
elevated, and always has 4 major parietals. All other
Thaumatodon have very fine or reduced ribbing.
Description. — Shell small, with 4~/s moderately tightly coiled
whorls. Apex and spire moderately and evenly elevated, last whorl
descending slightly more rapidly, H/D ratio 0.621. Embryonic
whorls, 1%, with fine, rather widely spaced radial riblets and smaller,
almost equally widely spaced spiral cords. Remaining whorls with
heavy, protractively sinuated radial ribs, 64 on the body whorl,
whose interstices are less than twice their width. Microsculpture of
fine radial riblets, five to eight between each pair of major ribs, and
much finer spiral riblets that are barely visible at 96 X magnification.
FIG. 196. a-c, Thaumatodon i -arauensis, new species. Cliff near Holonga, Vavau Island, Tonga. Holotype. BPBM 87860; d-f, Thaumatodon
corrugata, new species. Station 89, Mango Island, Lau Archipelago, Fiji. Holotype. BPBM 179940. Scale lines equal 1 mm. (MM).
460
SYSTEMATIC REVIEW
461
Sutures moderately impressed, whorls strongly rounded above,
flattened laterally. Umbilicus U-shaped, last whorl decoiling a little
more rapidly, contained 4.11 times in the diameter. Aperture ovate,
slightly compressed laterally, inclined about 15° from shell axis.
Parietal barriers 3, extending posteriorly more than three-sixteenths
of a whorl, plus two low accessory traces: upper high, bladelike,
weakly expanded and beaded above on posterior two-thirds, with
gradual anterior descension until just before termination; 2nd
slightly reduced in height, more strongly expanded and beaded above
on posterior half, with gradual anterior descension to termination
just in front of upper parietal; 3rd parietal lower than 2nd, expanded
and beaded above posteriorly, with anterior third a raised threadlike
ridge. Accessory traces very low and inconspicuous, located above
upper parietal, between 1st and 2nd parietals. Columellar barrier a
high lamellar ridge, lying parallel to plane of coiling, expanded and
beaded above posteriorly, with abrupt anterior descension to lip edge.
Palatal barriers 3, extending posteriorly almost three-sixteenths of a
whorl, with two accessory traces: lower palatal basal in position,
very high, markedly beaded above on posterior half, with rather
sharp anterior descension to lip edge; 2nd palatal equal in height to
1st, beaded above, with slightly more gradual anterior descension;
3rd palatal greatly reduced in height, weakly beaded above, with
much more gradual anterior descension, situated almost opposite
upper parietal. Accessory traces low and threadlike, located between
1st and 2nd, 2nd and 3rd palatals, deeply recessed. Height of
holotype 1.51 mm., diameter 2.44 mm.
Holotype. — Tonga: Vavau, cliff on Liku or north
side near Holonga at 200-350 ft. elevation. Collected by
I. E. Hoffmeister on July 10, 1928. BPBM 87860.
Range. — Vavau, Tonga.
Paratypes. — Same as list of material.
Material. - Tonga: Vavau (1 specimen, Zurich
502971), near Toulo (Station T-8), 2 miles south of
Neiafu (7 specimens, FMNH 152487); Leimatu'a (Sta-
tion T-17), 9 miles north of Neiafu (1 specimen,
FMNH 152329).
Remarks. - The single specimen reported by
Mousson (1871, pp. 10-11) as hystricelloides was
located in Zurich. It proved to be a somewhat
abnormal specimen of the species described here,
differing in possessing a 4th major palatal barrier and
in having a much narrower umbilicus. In some respects
it shows characters transitional to Thaumatodon
euaensis.
Despite intensive collecting on Vavau Island in
January of 1966, unfortunately during a period of
drought, only eight subadult dead examples were
obtained from leaf litter at two localities, north and
south of Neiafu.
GROUP OF Thaumatodon subdaedalea
Thaumatodon subdaedalea (Mousson, 1870).
Figure 197a-c.
Patula (Endodonta) subdaedalea Mousson, 1870, Jour, de
Conchy 1.. 18, pp. 117-118, pi. 7, fig. 6 - Mango Island. Fiji
Islands.
Helix (Patula) subdaedalea (Mousson I, Pfeiffer, 1876, Monog.
helic. viv., 7, p. 258.
Pitys subdaedalea (Mousson). Garrett, 1887, Proc. Zool. Soc.
London, 1887, p. 179.
Helix (Endodonta) subdaedalea (Mousson), Tryon, 1887, Man.
Conchol., (2), 3, pp. 64-65, pi. 12, fig. 26.
Endodonta (Thaumatodon) subdaedalea (Mousson), Pilsbry, 1893,
Man. Conchol., (2), 9, p. 27; Gude, 1913, Proc. Malacol. Soc.
London, 10, (5), p. 330.
Endodonta (Thaumatodon) maupiensis (Garrett) var. subdae-
dalea (Mousson), Germain, 1932, Ann. Inst. Oceanol., 12, (2), p.
45 (name only).
Diagnosis. — Shell larger than average, diameter 2.93-3.59 mm.
(mean 3.20 mm.), with 4?4-5'/2 very tightly coiled whorls. Spire and
apex moderately and evenly elevated, last whorl descending slightly,
H/D ratio 0.489-0.544 (mean 0.509). Umbilicus broadly V-shaped,
shouldered, slightly flattened inside, regularly decoiling, contained
2.66-3.58 times (mean 3.09) in the diameter. Sculpture usually of
widely spaced, strongly protractively sinuated, fine radial ribs whose
interstices are 3-8 times their width, often greatly reduced to
indistinguishable on body whorl (about 44-55, if all were distinct).
Microsculpture of fine radial riblets, crossed by much finer and more
crowded spiral riblets, on spire eight to twelve radials between each
pair of major ribs. Sutures deep, whorls strongly rounded above,
flattened laterally and basally. Aperture subovate, flattened laterally
and basally. inclined about 15° from shell axis. Parietal barriers 3,
extending posteriorly slightly more than one-quarter whorl, usually
with five, sometimes three or four, accessory traces: upper a high,
bladelike ridge, expanded and with three widely spaced beads on
posterior two-thirds, with gradual anterior descension; 2nd slightly
reduced in height, beading larger and more widely spaced, with more
gradual anterior descension, 3rd greatly reduced in height, beading
widely spaced, with very gradual anterior descension. Accessory
traces normally very low and thin, located above upper, one between
each pair of barriers and two below 3rd parietal; lower trace
intermediate in height between remaining traces and lowest parietal,
not beaded above. Columellar barrier high and bladelike, slanting
slightly downwards from plane of coiling, with gradual anterior
descension to lip edge; plus a raised threadlike trace, weakly
expanded and beaded above posteriorly, more deeply recessed within
aperture. Palatal barriers 4, extending posteriorly three-sixteenths of
a whorl, rarely with an accessory trace between 3rd and 4th palatals;
lower basal in position, high, thin, expanded and with two or three
large beads above, rather sharp descension to lip edge; 2nd and 3rd
equal in height, usually with three beads above, with progressively
more gradual anterior descension; 4th supraperipheral, greatly
reduced in height, much longer, with more gradual anterior
descension and deeper recession.
The large size, much finer and more widely spaced
sculpture, and wide umbilicus readily separate Thau-
matodon subdaedalea from T. decemplicata. T. corru-
gata from Mango Island differs slightly in size and
proportion (table CIX), possesses strong spiral cording
on the shell (fig. 196d) and has the microradial ribs
much finer and more lamellate. The beading on the
apertural barriers is much weaker in T. subdaedalea
than in other species of Thaumatodon.
Description. — Shell slightly larger than average with 5'/2 very
tightly coiled whorls. Apex and spire moderately and evenly
elevated, body whorl descending a little more rapidly, H/D ratio
0.536. Embryonic whorls 1%, sculpture of narrow, widely spaced,
rounded radial ribs, becoming more crowded near the end, crossed by
fine, relatively crowded spiral riblets. Postnuclear whorls with low,
gently rounded, broad, protractively sinuated radial ribs, whose
interstices are 3-6 times their width, that become indistinguishable on
latter part of body whorl. Microsculpture a lattice of very fine radial
riblets crossed by even finer and much more crowded spiral riblets.
Sutures deep, whorls strongly rounded above, somewhat compressed
laterally and on basal margin. Umbilicus broadly V-shaped, regularly
decoiling. margins weakly shouldered, whorls flattened inside,
contained 3.26 times in the diameter. Color light reddish-yellow-
brown, without darker maculations. Aperture elongately ovate,
compressed laterally, with evenly rounded outer and basal margin,
inclined about 15° from shell axis. Parietal barriers 3, extending
I abc I
FIG. 197. a-c, Thaumatodon subdaedalea (Mousson). Mango Island, Lau Archipelago, Fiji. Lectotype. Zurich 502974; d-f, Thaumatodon
hystricelloides (Mousson). Upolu, Western Samoa. Paratype. Zurich 502958. Scale lines equal 1 mm. (SG).
462
SYSTEMATIC REVIEW
463
slightly over one-quarter whorl, with five accessory traces: major
parietals high, bladelike. slightly expanded above, upper with four
narrow beads on posterior two-thirds and relatively sharp anterior
descension, middle with less distinct beading and more gradual
anterior descension, lower much reduced in height with two weak
beads above. Two accessory traces located below lowest parietal, one
between 2nd and 3rd, another between 1st and 2nd, and one above
1st parietal. Columellar barrier a narrow, bladelike ridge, almost
parallel to shell axis, reaching lip margin. Palatal barriers 4,
extending almost one-quarter whorl posteriorly, first 3 almost equal
in size, reaching lip margin, moderately expanded above with three
very weak, regularly spaced beads. Upper parietal a lower V-shaped
ridge, very weakly and irregularly beaded above posteriorly, slightly
recessed from apertural margin. Height of lectotype 1.69 mm.,
diameter 3.16 mm.
Lectotype. — Fiji: Lau Group, Mango Island.
Collected by E. Graeffe. Zurich 502974.
Range. — Mango, Vanua Mbalavu and Kimbombo
Islands, Lau Archipelago, Fiji.
Paratypes. — Zurich (2 specimens, Zurich 502974).
Material. — Fiji: Mango Island (Zurich, 3 speci-
mens), one-half mile southeast (Station 88) of Marona
at 200 ft. elevation, one-half mile inland (5 specimens,
BPBM 179912). Vanua Mbalavu (Station 95) at 1-200
ft. elevation (4 specimens, BPBM 179839); northwest
coast (Station F-8) on limestone outcrops in heavy
forest (2 specimens, FMNH 168144, collected October
3, 1970 by L. Price). Kimbombo, east islet, 100 yd.
inland at 50-150 ft. elevation in leaf mold (9 specimens,
BPBM 79102).
Remarks. — The specimens from Vanua Mbalavu
cannot be distinguished from those found on Mango.
Only two of the Kimbombo specimens were adult.
They are distinctly, but slightly, higher spired than
the Mango shells collected about the same time,
although the lectotype of T. subdaedalea is higher
than the Mango Island topotypes in the Bishop
Museum. The differences are not large enough to be
significant and the apertural barriers and ribbing are
identical. One juvenile specimen from Kimbombo
(BPBM 79078) had the radial sculpture reduced to
microriblets only.
Development of a second, closely related species
on Mango, Thaumatodon corrugata, was a surprising
discovery since T. subdaedalea has been found on
other islands of the Lau Group. T. corrugata differs
most obviously in the possession of marked spiral
cording on the body whorl (fig. 196d-e), but also is
distinctly smaller, with slightly fewer whorls, a
narrower umbilicus, and an insignificantly higher spire
in adult shells (table CIX, CX). Since both species
were collected on the same day and by the same
collector (Yoshio Kondo, August 14, 1938), there is no
question of yearly climatic conditions having produced
a dwarf population. The differences in size and
umbilical proportion undoubtedly are correlated, so
these represent one factor rather than two in separat-
ing the species.
Thaumatodon corrugata, new species. Figure
196d-e.
Diagnosis. — Shell of average size, diameter 2.81-3.04 mm. (mean
2.97 mm.), with 4:H-51/8 tightly coiled whorls. Apex and spire slightly
and evenly elevated, last whorl descending slightly more rapidly,
H/D ratio 0.500-0.540 (mean 0.518). Umbilicus broadly V-shaped,
regularly decoiling, contained 3.07-3.54 times (mean 3.30) in the
diameter. Major sculpture of very widely spaced, protractively
sinuated, low, irregular radial ribs crossed by evenly spaced, very
strong spiral cords that become slightly reduced on the upper part of
the whorls. Microsculpture of fine radial riblets crossed by much
finer and more crowded spiral riblets, spacing obscured by
irregularity of major radials. Sutures deeply impressed, whorls
strongly rounded above, flattened laterally above periphery and
basally. Aperture subovate, flattened laterally, inclined about 5°
from shell axis. Parietal barriers 3, extending posteriorly more than
one-quarter whorl, with four or five accessory traces: upper a very
high, thin blade, expanded and with four or five prominent beads
above on posterior two-thirds, with rather gradual anterior descen-
sion; 2nd equal in height posteriorly, usually with four beads above
on posterior half, with more gradual anterior descension; 3rd greatly
reduced in height, with very weak beading and quite gradual anterior
descension. Accessory traces located above upper parietal, one
between each pair and one or two below 3rd parietal. Columellar
barrier a low lamellar blade, slanting slightly downward from plane
of coiling, with gradual anterior descension almost to lip edge.
Palatal barriers 4, extending posteriorly three-sixteenths of a whorl:
lower basal in position, high, bladelike, expanded and with two beads
above, with rather sharp descension to lip edge; 2nd and 3rd equal in
height and beading to 1st, with progressively more gradual anterior
descension; 4th supraperipheral, much lower, with narrow, elongated
beads and very gradual anterior descension, more deeply recessed
within aperture.
The strong spiral cording, more reduced sculpture,
stronger beading, and small columellar barrier easily
separate T. corrugata from its very close relative, T.
subdaedalea. The Tongan species, T. vavauensis and
T. euaensis, have much wider and stronger ribbing on
the spire, are much higher and have narrower umbilici.
Description. — Shell of average size, with 5 very tightly coiled
whorls. Apex and spire evenly elevated, last whorl descending
slightly more rapidly, H/D ratio 0.511. Embryonic whorls 1%,
sculpture of widely spaced microradial riblets with spiral sculpture of
much lower and more closely spaced spiral riblets. Remaining whorls
with irregularly lamellate, very widely spaced, protractive radial ribs,
becoming greatly reduced to indistinguishable on body whorl with
secondary sculpture of strong spiral cords that are very prominent on
base and sides but slightly reduced above. Microsculpture of
extremely fine, somewhat lamellate, irregularly sinuated radial
riblets, about 15-20 between the major rib traces. Sutures deeply
impressed, whorls strongly rounded above, slightly flattened laterally
above the periphery and basally. Umbilicus broadly V-shaped,
contained 3.07 times in the diameter, with slightly shouldered
margin. Color light yellowish-red with irregular, slightly darker
reddish markings. Aperture ovate, compressed above periphery and
basally, inclined about 5° from shell axis. Parietal barriers 3, with
five accessory threadlike traces, all extending more than one-quarter
whorl. Upper 2 parietals high and lamellate for nearly entire length
with three subequal swollen beads on top. The beads are minutely
serrated. Lower parietal much reduced in height with two smaller
beads above. Columellar barrier thin, low, nearly parallel to plane of
coiling with very fine swollen beading above posteriorly. Palatal
barriers 4, extending slightly less than three-sixteenths of a whorl:
lower 3 high and bladelike, with three irregularly spaced, swollen and
serrated beads above; upper palatal slightly recessed, a low V-shaped
ridge with two slight beads evident above. Columellar and lower
palatal barriers reaching apertural margin. Height of holotype 1.55
mm., diameter 3.13 mm.
464
SOLEM: ENDODONTOID LAND SNAILS
Holotype. — Fiji: Lau Archipelago, Mango Island,
Station 89, one-half to three-quarters mile south-
southwest of Marona at 350-400 ft. elevation. Collected
by Yoshio Kondo on August 14, 1938. BPBM 179940.
Range. — Known only from Mango Island, Lau
Archipelago, Fiji.
Paratypes. — Same as list of material.
Material. — Mango Island, one-half to 1 mile
south-southwest of Marona (Stations 89, 90, 94) at
200-400 ft. elevation (5 specimens, BPBM 179940,
BPBM 179987, BPBM 180066).
Remarks. — No individuals at all intermediate in
sculpture between T. subdaedalea and T. corrugata
were seen. The former was collected southeast of
Marona at 200 ft. elevation, while corrugata was found
south-southwest of Marona at 200-400 ft. elevation.
The difference in sculpturing is absolute, and the
differences in proportion are significantly large.
Comparing just the adult material of T. subdaedalea
collected in 1934 from Vanua Mbalavu, Kimbombo,
and Mango, 5 specimens, with the adults of T.
corrugata, 5 specimens, there are 8 df (table CX). The
samples are different at the 0.05 per cent probability
level for diameter ("t" = 5.0676), the 2.5 per cent
probability level for D/U ratio ("t" = 2.65689) and not
significantly different ("t" = 1.7537) for H/D ratio.
I have chosen to consider corrugata a distinct
species, rather than a subspecies.
Thaumatodon laddi, new species. Figure 193d-f.
Diagnosis. — Shell very small, diameter 1.99-2.38 mm. (mean
2.15 mm.), with 37/8-4'/4 moderately tightly coiled whorls. Apex flat,
spire barely elevated, last whorl descending much more rapidly, H/D
ratio 0.483-0.538 (mean 0.513). Umbilicus broadly open, V-shaped,
only slightly decoiling, margins weakly shouldered, contained 3.13-
3.61 times (mean 3.35) in the diameter. Postnuclear sculpture of very
fine, protractively sinuated, broadly rounded radial ribs, about 180-
210 on the body whorl, whose interstices are 1-3 times their width,
coalescing partly on last portion of body whorl. Microsculpture of
very fine radial riblets, one to two between each pair of major ribs,
crossed by slightly finer and more crowded spiral riblets. Sutures
deep, whorls strongly rounded above and on basal margin,
compressed laterally. Aperture ovate, slightly to moderately
compressed laterally, inclined less than 10° from shell axis. Parietal
barriers 4, extending posteriorly one-quarter whorl, usually with
three, rarely four, accessory traces: upper high and thin, with three
or four very large beads above on posterior half to two-thirds,
weakly expanded, with sharp anterior descension; 2nd a very low
trace with remnants of beading above, terminating anteriorly slightly
in front of upper; 3rd parietal equal in height to 1st posteriorly, three
large beads above, with rather gradual anterior descension; 4th
parietal intermediate in height between 2nd and 3rd, strongly beaded
above on posterior half, with anterior third a low, raised lamella.
Accessory traces located above upper and below lower parietal,
usually with one trace between 3rd and 4th, occasionally one
between 1st and 2nd. Columellar barrier a raised lamellar ridge, lying
parallel to plane of coiling, with gradual anterior descension midway
across columellar callus. Palatal barriers 4, extending posteriorly
three-sixteenths of a whorl, with zero to two accessory traces; lower
at baso-columellar margin, high and thin, with three or four beads
above on posterior four-fifths, with abrupt descension to lip edge;
2nd almost identical to 1st; 3rd with more gradual anterior
descension; 4th lying almost opposite upper parietal, reduced in
height and beading prominence, with rather sharp anterior descen-
sion. Occasionally, one accessory trace is present between the 1st and
2nd, then 2nd and 3rd palatals.
The very small size, prominent beading on the
barriers an,d very crowded, rather irregular ribbing
identify this species. Thaumatodon corrugata and T.
subdaedalea have the 2nd parietal replaced by a
threadlike trace, the 1st palatal not at the baso-
columellar margin, very widely spaced ribbing on the
spire and are much larger. All other Thaumatodon
have much coarser ribbing and differ in barrier
structure details.
Description. — Shell very small, with 4'4 relatively tightly coiled
whorls. Apex flat, lower whorls of spire descending slightly, last
whorl rather rapidly, H/D ratio 0.528. Apical whorls 1%, sculpture of
widely spaced radial ribs with equally widely spaced spiral threads
present. Lower whorls with vague, irregular, rounded, protractive
radial ribs that sometimes coalesce, about 150 on first three-quarters
of body whorl, irregular on remaining portion. Microsculpture a fine
microlattice structure visible only under very high magnification,
with one or two radial riblets between each pair of major ribs.
Sutures moderately impressed, whorls rounded above, slightly
flattened above periphery and on lower basal margin. Umbilicus
broadly open, V-shaped, margins slightly shouldered, contained 3.13
times in the diameter. Color light reddish-yellow. Aperture ovate,
slightly flattened above periphery and on lower basal margin,
inclined less than 10° from shell axis. Major parietal barriers 4,
extending one-quarter whorl, numbers 2 and 4 reduced in height,
with four accessory threads. Upper parietal high and lamellate with
four widely spaced, minute but bulbous beads above; 2nd parietal
very much lower with two tiny beads posteriorly; 3rd parietal equal
in height to 1st with three globosely swollen beads posteriorly; 4th
parietal distinctly higher and with much more prominent beading
than 2nd. One large and one very fine trace above 1st parietal, third
trace between 3rd and 4th parietal, fourth trace below 4th parietal.
Columellar barrier a low, threadlike trace, parallel to plane of
coiling, reaching midway across columellar callus. Palatal barriers 4,
extending posteriorly three-sixteenths of a whorl, with two accessory
traces: lower at baso-columellar margin, weakly expanded above,
with three prominent beads on posterior half, with abrupt anterior
descension to lip edge; 2nd and 3rd equal in height to 1st, beading
much more bulbous, with more gradual anterior descension; 4th
supraperipheral, markedly reduced in height, with five slender beads
on posterior four-fifths, with rather sharp anterior descension.
Accessory trace located between 1st and 2nd palatals, large and
faintly beaded posteriorly; trace between 2nd and 3rd very small
(omitted from type figure). Height of holotype 1.25 mm., diameter
2.37 mm.
Holotype. — Fiji: Wangava Island, Station 27,
northeast end, one-quarter mile inland at 75 ft.
elevation. Collected by H. S. Ladd on July 22, 1934.
BPBM 166966.
Range. — Wangava Island, Lau Archipelago, Fiji.
Paratypes. - BPBM 166966 (17 specimens),
FMNH 168093 and FMNH 168095 (47 specimens).
Material. — Fiji: Wangava Island, northeast end,
one-quarter mile inland (Station 27) at 75 ft. elevation
(18 specimens, BPBM 166966); north end (Station F-4)
at 100 ft. elevation (47 specimens, FMNH 168093,
FMNH 168095, collected September 30, 1970 by L.
Price).
Remarks. — The beading on the apertural barriers
is proportionately more bulbous than in any other
SYSTEMATIC REVIEW
465
known species of Thaumatodon. All the 1934 speci-
mens were collected dead among leaf mould in a
pocket of coral rock. The 1970 specimens were
collected alive under limestone blocks in heavy forest.
In possessing a slightly shouldered open umbilicus
and in having reduced radial sculpture, T. laddi is very
similar to T. corrugata and T. subdaedalea, also from
the Lau Archipelago. In both of the latter species the
2nd parietal is represented by a low threadlike trace,
and the "3rd" and "4th" parietals of typical Thau-
matodon are the 2nd and 3rd in these species. T. laddi
has the 2nd parietal retaining posterior beading
(although greatly reduced in height) and the 1st
palatal moved to the baso-columellar margin. The
columellar barrier is reduced to a recessed, threadlike
trace. The fine crowded sculpture and much smaller
size of T. laddi also serve to differentiate it from the
other Lau Archipelago species.
Great pleasure is taken in naming this species
after Harry L. Ladd, long-time student of Pacific
geology and discoverer and describer of the very
important fossil endodontoids from the deep core
drillings on Bikini, Eniwetok and Funafuti.
Thaumatodon spirrhymatum Solem, 1973
Thaumatodon spirrhymatum Solem, 1973, Veliger, 16, (1), pp. 25-
30, figs. 1, 10-15, 17,6, 18, 21 - Thithia Island, Lau Archipelago,
Fiji.
Diagnosis. — Shell large for genus, diameter 2.96-3.45 mm.
(mean 3.23 mm.), with 4'/2-53/s normally coiled whorls. H/D ratio
0.441-0.564 (mean 0.494), apex and early spire usually flat. Umbilicus
broadly open, V-shaped, regularly decoiling, contained 3.17-3.92 times
(mean 3.53) in the diameter. Sculpture typical, body whorl ribs
thickened, becoming obsolete near aperture, major ribs 66-120 (mean
81.3) on body whorl. Periphery bikeeled, with both a sharply angled
supraperipheral and protruded threadlike peripheral. Parietal bar-
riers 4, extending posteriorly beyond line of vision, with four or five
accessory traces. Columellar barriers 2, lying parallel to plane of
coiling. Palatal barriers 4, extending posteriorly three-sixteenths of a
whorl, with three or four accessory traces. All major barriers beaded
above.
Thaumatodon spirrhymatum has a bikeeled body
whorl, relatively flat spire, and somewhat enlarged
sculpture. T. subdaedalea (Mousson, 1870) and T.
corrugata are similar in general appearance, but lack
the peripheral keeling and have very different sculp-
ture. T. laddi has much finer sculpture and also a
rounded periphery. Extralimital species differ in many
and obvious features, except for the Hawaiian Cooke-
concha stellulus (fig. 93), which differs in size,
sculpture, and apertural barriers, although having very
similar keeling pattern.
Holotype. — Fiji: Lau Archipelago, Thithia Island,
Station F-9, under rotting wood in deep forest on
limestone blocks, near Taruka Village on northwest
part of island at 10-100 ft. elevation. FMNH 176001.
Paratypes. - FMNH 168221 (36 specimens).
Remarks. — Full descriptive information on shell
and anatomy, plus illustrations are presented in Solem
(1973d). The keeling is immediately diagnostic when
combined with the retention of relatively normal
ribbing. Priceconcha and Zyzzyxdonta also have keeled
peripheries, but in the former the whorl count has
increased dramatically and the sculpture is virtually
absent, while in the latter, the peripheral ribs are
extended into "winglike" structures. These are not
duplicated elsewhere in the family.
Genus Priceconcha Solem, 1973
Veliger, 16, (1), pp. 20-21.
Endodontidae in which the major radial sculpture has been lost,
microsculpture absent on spire and greatly reduced on body whorl.
Shell larger than average, whorl count increased to about 7%. Apex
and spire strongly and almost evenly elevated, slightly rounded
above, H/D ratio about 0.555. Umbilicus broadly V-shaped, regularly
decoiling, contained about 2.90 times in the diameter, margins
strongly rounded. Periphery with strong, threadlike keel. Parietal
barriers 5, with ten or eleven accessory traces, extending more than
one whorl posteriorly. Columellar barriers 2, with two accessory
traces. Palatal barriers 5, with four or five accessory traces. All
major barriers beaded above. Radular structure typical of family.
Genitalia with penial insertion of spermathecal shaft, epiphallic zone
in penis, and elongation of vas deferens-free oviduct zone. Pallial
organs narrowed and elongated as adjustments to space problems.
Type species. — Priceconcha tuvuthaensis Solem,
1973.
Priceconcha was collected on tree trunks and thus
represents at least a semi-arboreal taxon in a normally
strictly terrestrial family. Libera bursatella has been
found in the axils of Freycinetia on Tahiti, and some
Cookeconcha occur in moss on tree trunks, but
otherwise the family is terrestrial.
Conchologically, Priceconcha is distinguished by
its great degree of sculpture reduction, drastically
increased whorl count, extremely long parietal bar-
riers, and peripheral keel. The sculpture reduction
occurred despite the relatively small size of the shell
and probably correlates with the habitat shift. In the
field and during first sorting, this species was thought
to be a very small trochomorphid, an indication of the
atypical shell form and appearance. Anatomically,
Priceconcha agrees with the Thaumatodon- Aaadonta
pattern except for changes correlated with the greatly
increased whorl count. Full discussion of these changes
is given in Solem (1973d) and is not repeated here.
Priceconcha tuvuthaensis Solem, 1973
Priceconcha tuvuthaensis Solem, 1973, Veliger, 16, (1), pp. 20-25,
figs. 2-9, 16, 17, a, 19-20 - Tuvutha Island, Lau Archipelago,
Fiji.
Diagnosis. — Shell larger than average, diameter 4.05-4.54 mm.
(mean 4.29 mm.), with 7%+ to 75/s very tightly coiled whorls. Apex
and spire strongly elevated, H/D ratio 0.528-0.587 (mean 0.558).
Umbilicus broadly V-shaped, regularly and evenly decoiling, contain-
ed 2.73-3.07 times (mean 2.90) in the diameter. Shell surface smooth,
except for traces of microreticulations on last two whorls and faint
growth striae. Periphery with a strong protruding keel. Parietal
barriers 4, extending posteriorly more than one whorl, with ten or
eleven accessory traces. Columellar barriers 2, lying parallel to plane
of coiling, with two accessory traces. Palatal barriers 5, extending
posteriorly more than one whorl, with three or four accessory traces.
All major barriers beaded above.
466
SOLEM: ENDODONTOID LAND SNAILS
The high whorl count, lack of sculpture, high
spire, peripheral keel, and very long beaded barriers
separate Priceconcha tuvuthaensis from any Thau-
matodon and the other Lau endemic, Zyzzyxdonta.
The larger Society Islands Nesodiscus are quite similar
in overall appearance, but differ in size, anatomy,
reduction of apertural barriers, and origin.
Holotype. - • Fiji: Lau Archipelago, Tuvutha
Island, west coast in heavy forest at 100 ft. elevation.
Collected on tree trunks during wet spell by Laurie
Price on October 2, 1970. FMNH 168131.
Paratypes. - FMNH 168136 (2 specimens).
Remarks. — Illustrations of shell, radula, and
anatomy were given in Solem (1973d) and are not
repeated here. The large (5.6-7.6 mm.) Nesodiscus with
equivalently reduced sculpture, N. cretaceus, and N.
fabrefactus, are very similar in general appearance, but
differ both in barrier features and much wider
umbilici.
a
Genus Zyzzyxdonta, new genus
Endodontidae with typical apical sculpture, postnuclear whorls
with widely spaced radial ribs protruded into hollow, winglike
structures (fig. 198c) at the carinated periphery. Whorls about 5,
rather loosely coiled, apex flat, spire slightly elevated. Body whorl
with protruded, keeled periphery, not descending more rapidly, with
distinct subperipheral sulcus. Umbilicus widely open, U-shaped, last
whorl not decoiling as rapidly. Apertural barriers consisting of 3
parietals, a single columellar that slants downwards, and 3 long
palatals. All barriers with large, swollen and serrated beads above.
Anatomy unknown.
Type species. — Zyzzyxdonta alata, new species.
The beaded apertural barriers and general appear-
ance of the microsculpture indicate affinity to Thau-
matodon and Aaadonta. The extremely depressed
form (table CIX), sharply protruded periphery, and
peculiar development of the remaining radial ribs into
winglike protrusions immediately separate Zyzzyx-
donta alata from both genera. In the exact form of the
barriers and umbilicus, Z. alata is much more similar
to Thaumatodon than to Aaadonta. Unquestionably,
it is a local derivative of Thaumatodon, but the
morphological gap is large enough to demand generic
separation. Priceconcha also is keeled, but in a
different way and has very different sculpture.
Species of the genus Aaadonta represent the
extreme development of fine sculpture and have the
westernmost range of existing Endodontidae. The
single known species of Zyzzyxdonta represents the
extreme gross sculptural development within the
family and is at the southwestern fringe of dis-
tribution. It was thought appropriate that their names
be as widely separated as their sculpture.
Zyzzyxdonta alata, new species. Figure 198a-c.
Diagnosis. — Shell slightly larger than average, diameter 3.62-
4.34 mm. (mean 4.03 mm.), with 41'2-5 relatively loosely coiled whorls.
Apex and spire flat, lower whorls descending moderately, last whorl
not descending more rapidly, H/D ratio 0.368-0.427 (mean 0.379).
abc
Flo. 198. a-c, Zyzzyxdonta alata, new species. Northeast quarter
of Navutu-I-Loma, Yangasa Cluster, Lau Archipelago, Fiji.
Holotype. BPBM 167018. Scale line equals 1 mm. (MM).
SYSTEMATIC REVIEW
467
Umbilicus broadly open, U-shaped, somewhat contracted by tighter
coiling of last whorl, contained 3.28-4.37 times (mean 3.72) in the
diameter. Whorls sharply angulated, ribs on angulation protruding
into hollow, winglike structures (fig. 198), varying in number from
21-27 on body whorl. Sculpture of fine radial riblets with a few
stronger ribs becoming protruded into the hollow winglike structures
at the periphery. Sutures hidden by extended wings, whorls flat
down to strongly protruded periphery, with evenly rounded basal
margin to shouldered umbilicus. Aperture subquadrangular, with
strongly protruded periphery, inclined about 30° from shell axis.
Parietal barriers 3, extending posteriorly to line of vision: upper high,
thin, expanded and with five or six prominent beads above on
posterior three-quarters, with gradual anterior descension from end
of beaded portion; 2nd and 3rd progressively slightly lower, with
finer beading, and more gradual anterior descension. Usually with an
accessory trace, moderately recessed, between 1st and 2nd parietals.
Columellar barrier moderately elevated, bladelike, expanded above
and weakly beaded posteriorly, slanted down from plane of coiling,
with gradual anterior descension almost to lip edge. Palatal barriers
3, extending posteriorly one-quarter whorl: lower 2 subperipheral,
equal in height, with four or five prominent beads above, with sharp
descension to lip edge; 3rd supraperipheral, greatly reduced in height
and length, moderately recessed, with less conspicuous beading
above.
Protrusion of the major ribs into winglike hollow
extensions on the periphery is unique to Zyzzyxdonta
alata among the known endodontids. The character of
the apertural barriers, with the major ribs strongly
beaded above, relates Z. alata to Thaumatodon, but
the very depressed shape, carinated periphery, and
peculiar rib structure are diagnostic.
Description. — Shell relatively large, with 4Vz rather loosely
coiled whorls. Apex flattened, slightly depressed below plane of
winged rib extensions, lower whorls descending slightly, H/D ratio
0.382. Embryonic whorls I'/z, sculpture reduced in prominence,
consisting of very inconspicuous, quite widely spaced radial riblets
with a few, even more widely spaced, much lower spiral cords. Lower
whorls with very fine radial growth striae and a few widely spaced
major ribs, 23 on the body whorl, that become protruded into
winged, cuplike structures at the periphery. Under 96 x mag-
nification a vague microspiral sculpture is barely visible. Sutures
shallow, margined above by peripheral keel surmounted by rib
extensions. Umbilicus widely open, slightly contracted by coiling of
last whorl, U-shaped, contained 4.37 times in diameter, with
relatively sharply rounded margin. Aperture roughly subquadrangu-
lar, with rostrate lateral extension. Parietal barriers 3, extending
posteriorly to line of vision: upper parietal quite high and lamellate
with four large, regularly spaced, equal-size beads above; 2nd
parietal almost equal in height, anterior portion slightly lower, with
three regularly spaced and shaped beads above; 3rd parietal a
moderately high threadlike ridge with only vague superior beading.
Columellar barrier thin, high, slanting slightly downward across
columellar callus, reaching apertural margin, with weak indications
of posterior beading. Palatal barriers 3, long, extending one-quarter
whorl: lower 2 high lamellae, relatively thin, with five regularly
spaced beads above, reaching apertural margin with very rapid
anterior descension, subperipheral in position; 3rd palatal a
narrower, much lower ridge with five thin beads above, supraperi-
pheral in position. Height of holotype 1.65 mm., diameter 4.31 mm.
Holotype. — Fiji: Lau Archipelago, Yangasa clus-
ter, Navutu-i-Loma, Station 28, northeast quarter of
island on a limestone outcrop, 150 yards inland at 100
ft. elevation. Collected by H. S. Ladd on July 24, 1934.
BPBM 167018.
Range. — Navutu-i-Loma, Yangasa cluster, south-
east Lau Archipelago, Fiji.
Paratypes. — Same as list of material.
Material. — Fiji: Lau Group, Navutu-i-Loma,
northeast quarter of island (Station 28), 150 yd.
inland, at 100 ft. elevation (7 specimens, BPBM
167018, USNM 664707, BPBM 167054); Station F-2 at
50-100 ft. elevation (1 specimen, FMNH 168061)
collected September 28, 1970 by L. Price).
Remarks. — At first glance, the carinated body
whorl and the very peculiar winged extensions of the
major ribs would suggest that Z. alata is a very
isolated species. The character of the apertural
barriers, however, immediately related it to Thaumato-
don. The parietal trace probably is a remnant of the
4th parietal found in many Thaumatodon. Barrier
placement and umbilical shape are much as in the
subdaedalea group, but the shell form and ribbing are
so distinctive that generic separation is warranted.
Unfortunately, no live material of this very unusual
species was collected.
There is a superficial similarity to the much larger
(diameter about 9 mm.) trochomorphid snail, Kondoa
asteriscus (H. B. Baker, 1941, p. 272, pi. 65, figs. 13 -
15) from Truk, Caroline Islands. This species has the
carinated periphery studded with solid triangular
projections that do not originate from radial ribs, while
in T. alata the winglike projections are hollow
extensions of a few radial ribs.
Other Endodontidae with strongly protruded
peripheries include the Austral Islands Australdonta
magnasulcata (fig. 127a-c) and the Hawaiian Cooke-
concha stellulus (Gould) (fig. 93a-c). The former does
not have extraordinary rib enlargement, but in the
latter species the major ribs are greatly reduced in
number and very high.
Genus Aaadonta, new genus
Endodontidae in which the apical and postapical major radial
sculpture is absent. Apex with about 20 fine and squiggly spiral
cords, secondary radial irregularities near end of nuclear growth.
Postnuclear sculpture of fine radial riblets with varyingly prominent
lateral beads arranged in spiral series that represent continuations of
the apical spirals and appear as secondary spiral cords. Apex and
spire usually markedly elevated (flat in kinlochi), normally spire
protrusion two-thirds to nine-tenths body whorl width, less in
fuscozonata depressa. Body whorl with protruded keel, except
pelewana. Whorls 5-6, tightly coiled. Umbilicus usually very narrow
to closed, secondarily widened in angaurana and kinlochi. Major
parietals 3 (reduced to 2 in irregularis), beaded above, sometimes
(constricta and irregularis) with a single accessory trace. Columellar
hairier absent (some constricta), normally 1, sometimes (fuscozo-
nata) 2, usually parallel to plane of coiling, slightly declined in
pelewana and fuscozonata. Major palatals 3, 4, or 5, all strongly
beaded, accessory traces present in pelewana, fuscozonata, irregu-
laris. Pallial region typical, with very short rectal kidney arm.
Hermaphroditic duct convoluted for one-third of length, remaining
portion normal. Talon elongated with head slightly to moderately
bulbous, shaft tapered. Epiphallus about half length of penis, vas
deferens entering through a valve, internally with two pilasters that
variously expand, split or fade out in penis. Penial retractor arising
from diaphragm, inserting on penis-epiphallus junction. Spermatheca
inserting on penial side of penioviducal angle. Atrium relatively long.
Radula without unusual features.
468
SOLEM: ENDODONTOID LAND SNAILS
Type species. — Endodonta constricta Semper,
1874.
Under light microscope examination, the apical
sculpture mimics the fine spiral cording seen in some
Charopidae. At 1,000-3,000 X magnification (figs. 28e;
29a) the typical spiral squiggles of the Endodontidae
are evident. While many Charopidae have fine spiral
cords which appear wavy near the end of the apex, this
is a secondary phenomenon caused by low radial
swellings underlying the spiral cords. These cords are
never formed in the fashion seen in Aaadonta.
Postnuclear sculpture of Aaadonta (figs. 28c-e; 29b)
consists solely of microradial riblets with vague
secondary spiral additives. Despite the quite different
macroscopic appearance of this sculpture, it differs
from the typical endodontid pattern only by the
absence of any major radial ribbing on either the apex
or the postnuclear whorls. Such a loss could be the
result of a single mutation, since the major radial
sculpture is additive to the basic microsculpture
pattern (pp. 30-33).
While providing the most obvious differentiating
feature, other characters are more significant in
providing generic separation. The beaded apertural
barriers, insertion of the spermatheca on the penial
side of the penioviducal angle, and development of an
epiphallic region with complex vas deferens entrance
are characters shared with Thaumatodon from the
Lau Archipelago of Fiji, Tonga, Ellice Islands, Western
Samoa, and Rarotonga, and the Thaumatodon deriva-
tive genera in Lau, Priceconcha and Zyzzyxdonta.
Aaadonta has a rostrate periphery, generally very
elevated spire, narrow umbilicus, a shorter rectal
kidney arm, longer atrium, longer epiphallus, and long
tapering talon. A more comprehensive comparison has
been given above (p. 444). Thaumatodon has normal
apical sculpture and, at least on the upper spire,
prominent postnuclear radial sculpture. Only in the T.
laddi-corrugata-subdaedalea complex of Lau is there
a clear tendency toward great reduction and loss of
sculpture. In these cases both macro- and micro-
sculpture are affected by the reduction. Since there is
no loss or reduction in the microsculpture of Aaa-
donta, I consider it improbable that there was gradual
loss of major radial sculpture. In genera such as
Nesodiscus and Endodonta, gradual reduction in
major sculpture is followed by gradual loss of the
microsculpture before the apical and early spire major
sculpture disappears. Only in the group of Libera
dubiosa Ancey, L. spuria Ancey, and L. garrettiana is
there progressive loss of major sculpture without
concomitant loss of microsculpture. All three of these
species retain major apical radials and an increase in
prominence of secondary spiral cording is inversely
correlated with decrease in major radial ribs. Under
the circumstances, postulation of major radial rib loss
by mutational change is an acceptable hypothesis.
Aaadonta is the only Micronesian genus of
Endodontidae. While the Miocene Cookeconcha sub-
pacificus (Ladd, 1958) and the Pleistocene- Pliocene
Minidonta inexpectans (Ladd, 1958) are known from
the deep-core drillings on Bikini, they belong to the
anatomically and conchologically most generalized
groups. Anatomical features and the denticle beading
relate Aaadonta to Thaumatodon, which also is the
geographically nearest extant endodontid genus. In
general, the high spire of Aaadonta is otherwise
characteristic of brood chamber taxa (Libera, Pseu-
dolibera, Gambiodonta), where deflected growth is
required to permit development of a sufficiently deep
umbilicus. Of those Endodontidae with a SP/BWW
ratio of 0.640 or greater, 18 have brood chambers
[Pseudolibera, Taipidon semimarsupialis, four (of six)
Gambiodonta, 12 (of 19) Libera], three are Nesodiscus,
and only Anceyodonta ganhutuensis and A. sex-
lamellata (Pfeiffer) agree with the seven (of nine)
Aaadonta in having high spires but tiny umbilici.
Similarly, the rostrate periphery is unusual in forms
that lack a brood chamber. Of 31 taxa with rostrate
peripheries, there are seven Libera, three Gambio-
donta, five Endodonta, five Nesodiscus, six Aaadonta,
three Thaumatodon derivatives (T. spirrhymatum,
Zyzzyxdonta alata, and Priceconcha tuvuthaensis),
and two isolated species — Cookeconcha stellulus and
Australdonta magnasculcata.
Median size of rostrate Aaadonta is 4.07 mm. in
diameter compared with 5.85 mm. for the remaining 25
rostrate taxa.
Primarily because of the sculptural and shape
alterations, Aaadonta seems to be quite distinctive
conchologically, but the differences are relatively few.
Both in shell characters and penial anatomy,
Aaadonta is the most advanced endodontid genus.
Within the genus, no clear hierarchy can be recog-
nized. A. kinlochi is specialized only in its flattened
spire and relatively large size. The largest species, A.
irregularis, has reduced barrier numbers with only 2
major parietal and 3 major palatals. A. constricta has
the greatest development of a rostrate periphery and
strongly rounded whorls, although having the most
conservative barrier pattern. A. angaurana has quite
laterally compressed whorls and only 4 palatal
barriers. Variation in the recession and prominence of
the columellar barrier is exceptionally large, only A.
fuscozonata having a 2nd columellar, while in some
races of A. constricta the barrier is so deeply recessed
that it can be seen only by extreme tilting of the
aperture.
A. fuscozonata depressa, A. f. fuscozonata, and A.
pelewana form an obviously monophyletic series. The
first two have weakly rostrate peripheries, the latter
an obtusely rounded periphery. All other Aaadonta
have a strongly rostrate periphery. Their size and
shape also is quite distinctive. In both races of A.
fuscozonata, the beading on the upper parietal barrier
is distinctly finer and more widely spaced than on the
lower 2. In A. pelewana, the beading is equal in
CN
Ol
+
CO
CN|
+
in
Ol
0|
+
CO
o
+
(N
o
•a
3.
(N
<N
in
co
CO
c-'
CO
CO
CO
CO
o
in
o
o
m
in
o
c-
co
CO
in
CO
o
CO
•<*
c^
o
co'
i-(
CO
CO*
^
CO
in
,3 CN
1 ^
oo'
in
in
CO
CO
m
+
co
in
+
(M
CO
OO
00
CO
m
m
So'
CO
>x
c-
m
CM
CO
^v
in
in
CO
CO
CO
CO
in
CO
CN
in
i
CO
in
CO
-v,
in
Tjl
o
t-
in
CM
o
0
CM
o
CO
CO
o
c-
oo
r-
CO
CO
c^
o
o'
0
o'
o'
o'
o'
•3
1
rt
CO
CM
CO
o
in
CN
&
c-
CO
CO
CN
r-\
co
CO
CO
m
CO
CO
Q
.
~^
o
o
0
o
0
0
K
cf
c^
CO
C4
0
o'
t-
t^
o'
CO
CO
r-
e-
m
CO
CO
o'
o'
o
0
0
0
in
CO
in
o
CO
CO
CO
o
of
oo
O
I
CN
X!
O
E
nj
Q
CO
CO
CO
c-
oo
CN
CO
CO
CM
5?
CO
CO
CO
co"
o
•*'
in
co'
CO
c^
CN
•*'
C-
O>
CO*
N
OO
in
CO
CO
o
t-
CN
•*'
co-
co
JS
oo
CO
X
o
CN
CN
in
CN
i
cn
c-
CM
CN
CO
(N
OT
CN
CN
CN
C-
CN
O
OJ
CN
m
co
CN
10
in
CN
in
co
CN
m
53-
CN
OO
O
<N
CO
co'
CO
in
o
CO
en
in
o c -a
w 4) U
| E £
XI -^i r-
Eu c
_ 4) rt
5 o, x
Z co W
CO
CO
CO
c-
2
"3
r>
c
c
•T
<a
o
2
3
c
N
O
OJ
O
£
rt
o
O.
^3
i-H
rt
J3
(U
c
CO
E
W-«
'^*
o
rt
o
rt
(rt
o
XI
.X
Name
pelewana
fuscozonat
fuscozonat
constricta
constricta
constricta
angaurana
irregularis
kinlochi
469
470
SOLEM: ENDODONTOID LAND SNAILS
prominence on all parietals in the majority of
specimens examined, but weaker in a few. A. pelewana
and A. f. fuscozonata agree in having the 2nd palatal
reduced in size, while in A. f. depressa the 2nd palatal
is equal in size to the 1st and 3rd. The nominate race
of fuscozonata has the palatals extending about one-
half whorl, while in the other two taxa they extend
less than one-quarter whorl. Ranking of depressa as a
subspecies and pelewana as a species is arbitrary and
may not be supported when more material is available.
Probably all three should be considered species.
When specimens of several species are available
for direct comparison, the differences are obvious and
striking. Even without other material, A. pelewana, A.
fuscozonata, and A. kinlochi are unmistakable. A.
pelewana is the only species that lacks a prominent
supraperipheral sulcus and does not have a rostrate
periphery; A. fuscozonata is characterized by its
diminutive size and tiny umbilicus (table CXI); while
A. kinlochi is the only species with a flat or nearly flat
spire. Differences between A. constricta, A. angaur-
ana, and A. irregularis are less dramatic. The first two
overlap in size, but when ratios are plotted (fig. 202)
can readily be separated, while the very large A.
irregularis has a reduced barrier complement. A.
pelewana and A. fuscozonata also can be distinguished
on the basis of plotted ratios (fig. 205).
There was considerable variation in the percentage
of adult specimens present in each taxon collected by
the Bishop Museum Micronesian Expedition (table
CXII). Those forms taken at only a single station
(constricta komakanensis, angaurana, and kinlochi)
were 9.5-16.8 per cent adult while the three species
TABLE CXII. - PERCENTAGE OF ADULTS IN AAADONTA
Species known from: -
Single stations -
Total Number of
collected adults
constricta komakanensis
42
128
173
82
21
51
36
20
12
3
4
3
7
4
14
29
21
10
11
14
3
8
3
3
3
6
Per cent
adults
9.5
10.9
16.8
25.6
37.0
21.6
38.9
15.0
66.7
100.0
75.0
100.0
85.7
taken only as scattered individuals (constricta babel-
thuapi, fuscozonata depressa, and irregularis) were
nearly all adult. The two species taken in fair numbers
at more than one station (constricta constricta and
fuscozonata fuscozonata) ranged widely in inter-
mediate percentages.
Anatomically, Aaadonta agrees with Thaumato-
don and Priceconcha in having the spermatheca enter
the base of the penis instead of merging into the free
oviduct channel to form a vagina, and in having a
reflexed epiphallic portion of the penis lying
morphologically above (although topographically
below) the penial retractor insertion. In Aaadonta the
reflexed epiphallic portion is about one-half of the
penis length, while in Thaumatodon it may be only
one-quarter the length. All other Pacific Island
endodontid genera have the vas deferens entering
laterally on a straight penis at or markedly below the
penial retractor insertion, and the spermatheca merges
with the free oviduct to form a true vagina (except in
Rhysoconcha).
In the only Thaumatodon dissected in entirety, T.
hystricelloides and T. euaensis, there are peculiar
glandular patches on the uterus apex and base (fig.
191b). They were not found in any other species
dissected. Priceconcha tuvuthaensis was so heavily
parasitized that this section of the genitalia could not
be studied in detail.
Materials of A. c. constricta, A. c. komakanensis,
A. c. babelthuapi, A. kinlochi, and A. fuscozonata
fuscozonata were available for study. Presumed wet
examples of A. irregularis in the Bishop Museum were
not located, and only terminal fragments of A. f.
depressa were seen. A. angaurana and A. pelewana
were represented only by dead shells. Few differences
were noted between the three species dissected in
detail. The free oviduct is much longer in A.
fuscozonata, which has 5%-6'/2 whorls, than in A.
kinlochi, which has 45/8-5!/2 whorls, and A. constricta
constricta (5'/s-6 whorls) is intermediate in oviduct
length. These differences were not quantified because
of difficulties in handling the material, but are obvious
through inspection of Figures 199b, e, and 200b. In A.
kinlochi (fig. 200b) the hermaphroditic duct is more
convoluted than in the other two species. Possibly this
has resulted from the reduction in whorl count found
in that species. Otherwise observed differences lie in
penis size and pilaster patterns. A. kinlochi (fig. 200c)
and A. fuscozonata have one pilaster splitting to form
a weak pocket, while in A. c. constricta (fig. 199d) two
pilasters merge to form a similar pocket. The relative
size of the pilaster arms varies rather widely within
each species. Data on penis length are as follows:
A. kinlochi 1.7 mm.
A. f. fuscozonata 1.6-1.8 mm.
A. c. constricta 1.4 mm.
Unfortunately, it was not possible to dissect two
species using material taken at the same station. There
NIC
PR
GG
PR
UT
HG
UT,
FIG. 199. Anatomy of Aaadonta: a-d, Aaadonta constricta constricta, BPBM 159938. a, pallial region; b, genitalia with ovotestis
omitted, c, diagram of carrefour region, dotted lines indicating uncertain channel patterns, d, detail of epiphallus and apical part of penis; e-f,
Aaadonta fuscozonata fuscozonata, BPBM 158778. e, genitalia with ovotestis omitted, f, pallial region.
471
472
SOLEM: ENDODONTOID LAND SNAILS
GG
GT
FIG. 200. Anatomy of Aaadonta kinlochi, BPBM 158778: a,
pallial region and lower intestinal loops; b, genitalia; c, detail of
penial complex.
were no obvious structural differences suggesting
character displacement in penial pilaster pattern.
Possibly the size difference is sufficient to isolate
sympatric taxa.
Pallial region proportion also differed, A. c.
constricta having a shorter and broader region (fig.
199a) than either A. f. fuscozonata (fig. 199f) or A.
kinlochi (fig. 200a). The ratio of kidney length to total
pallial cavity length was least in A. constricta (1.9-2.0),
intermediate in A. fuscozonata (2.5-2.9), and greatest
in A. kinlochi (3.1-3.4). The differences in cross-
sectional whorl area between the tightly coiled A.
fuscozonata and A. kinlochi with its fewer, more
loosely coiled whorls undoubtedly are considerable.
Hence a thicker kidney in A. kinlochi could result in
equivalent kidney volume in a relatively shorter
distance. Thus the higher pallial length/kidney length
ratio of A. kinlochi does not conflict with the
shortened pallial cavity that accompanies reduced
whorl counts.
Aaadonta is restricted to the Palau Islands.
Species distribution is summarized in Table CXIII.
Only A. constricta babelthuapi has been collected on
two islands, Ngemelis and Babelthuap, with the
former record based on a single individual. Peleliu,
which has been relatively well collected, yielded
examples of A. c. constricta, A. irregularis, and A.
fuscozonata depressa. Koror, the next best sampled
island, has A. c. komakanensis and A. f. fuscozonata.
Although only a single station on Angaur yielded
endodontids, there are two endemics, A. angaurana
and A. kinlochi. Single stations on Ngemelis and
Babelthuap yielded the same race of A. constricta.
More intensive collections are needed from both
islands. An undescribed charopid was collected on
Auluptagel, but no examples of Aaadonta. Quite
probably additional species will be found.
Sympatric occurrence of Aaadonta species was
found several times. Unfortunately, it was not possible
to dissect these sympatric forms. On Koror, A.
constricta komakanensis and A. f. fuscozonata were
found at Station 221, with the former dominant and
comprising 78 per cent of the sample. On Peleliu, A. c.
constricta and A. irregularis were taken at Stations
182 and 201, with the former comprising 93-96 per cent
of the samples. At Station 203 on Peleliu five
Aaadonta specimens included one A. c. constricta and
two each of A. irregularis and A. fuscozonata
depressa. On Angaur, both A. angaurana and A.
TABLE CXIII. - DISTRIBUTION OF AAADONTA
Palau Islands
S>
c
2
<u
o,
o
<u
00
i
CX
3
•8
CO
constricta
c. constricta.
X
c. babelthuapi. . . .
£. komakanensis. .
irregularis.
angaurana
kinlochi
fuscozonata
f_. fuscozonata. . . .
f_. depressa
pelewana
X
X
X
X
SYSTEMATIC REVIEW
473
kinlochi were collected at the same station, with A.
kinlochi (57.5 per cent) more plentiful. This was a
thanatocoenosis, however, with no living A. angaur-
ana and only 12 of 173 A. kinlochi (6.9 per cent) taken
alive.
The above data suggest a few possibilities for
field investigation. Is A. irregularis anywhere common
and dominant in numbers over A. constricta'? What
are the ecological differences between the two species?
Is A. angaurana extinct and stratigraphically sepa-
rated from the material of A. kinlochi'? Why were no
examples of A. c. komakanensis present at Stations
217 and 219 and how does the ecology of that race and
A. f. fuscozonata differ?
KEY TO THE GENUS Aaadonta
1. Spire strongly elevated, H/D ratio usually much more than
0.460 , 2
Spire flat or only barely protruding above peripheral keel, H/D
ratio less than 0.440 Aaadonta kinlochi, new species
2. Umbilicus minute, D/U ratio more than 13 3
Umbilicus narrowly to moderately open, D/U ratio less than 11.
4
3. Major palatal barriers 3; Peleliu Island.
Aaadonta fuscozonata depressa, new subspecies
Major palatal barriers 5; Koror Island.
Aaadonta fuscozonata fuscozonata (Beddome, 1889)
4. Shell diameter more than 3.25 mm.; periphery of aperture
rostrate 5
Shell diameter less than 3.00 mm.; periphery of aperture
obtusely rounded Aaadonta pelewana, new species
5. Shell diameter less than 4.5 mm 6
Shell diameter more than 4.5 mm.
Aaadonta irregularis (Semper, 1874)
6. Mean D/U ratio substantially more than 5.00 7
Mean D/U ratio substantially less than 5.00.
Aaadonta angaurana, new species
7. Mean diameter about 3.9-4.2 mm 8
Mean diameter about 3.5 mm.
Aaadonta constricta babelthuapi, new subspecies
8. Columellar barrier prominent (fig. 204a); mean H/D ratio near
0.660; mean D/U ratio near 7.5; Koror Island.
Aaadonta constricta komakanensis, new subspecies
Columellar barrier inconspicuous (fig. 203b); mean H/D ratio
near 0.570; mean D/U ratio near 5.6; Peleliu Island.
Aaadonta constricta constricta (Semper, 1874)
Aaadonta constricta (Semper, 1874)
The development of a supraperipheral sulcus and
shouldering of the whorls is carried furthest in A.
constricta of all Aaadonta. Intermediate in size
between the very small fuscozonata-pelewana group-
ing and the large irregularis-kinlochi pair, only A.
angaurana is apt to be confused on the basis of size
(table CXI). It differs in having much flatter whorls, a
more open umbilicus (D/U ratio 3.83-4.70) and only 4
palatal barriers. A. constricta is the most widely
distributed species, having been collected on Koror,
Peleliu, Babelthuap, and Ngemelis (table CXIII).
Three subspecies are recognized:
A. constricta constricta (Semper, 1874) from
Peleliu Island is more depressed (mean H/D ratio
AAADONTA
.£ kinlochi
•^constricla constricta
0 constricta babelthuapi
fj constricta komakanensis
O irregularis
3.2 3.4 3.6
3.8 4.0
4.2 4.4
Diameter
4.6
48
5.0 5.2
5.4
5.6
FIG. 201. Size and shape variation in Aaadonta kinlochi, A.
constricta, and A. irregularis.
0.570), has a wider umbilicus (mean D/U ratio 5.58),
only a weak columellar barrier, and less strongly
rounded whorls;
A. constricta komakanensis, new subspecies from
Koror Island, is a high shell (mean H/D ratio 0.660),
with narrow umbilicus (mean D/U ratio 7.47), promi-
nent columellar barrier, a much less compressed lower
palatal wall, and a greatly reduced 3rd parietal barrier;
A. constricta babelthuapi, new subspecies from
Babelthuap and Ngemelis is a small, high shell (mean
H/D ratio 0.647), with an umbilicus of intermediate
size (mean D/U ratio 6.50), usually no columellar
barrier visible, and very strongly rounded whorls.
The differences between these subspecies are of a
lesser magnitude in terms of barrier complement than
.645
.615 -
constricla
465
3.5 4.0
4.5
5.0 5.5
D/U Ratio
6.0
6.5
FIG. 202. Proportionate differences between Aaadonta angaurana
and A. c. constricta.
474
SOLEM: ENDODONTOID LAND SNAILS
are those between A. f. fuscozonata and A. f. depressa,
but reach very high levels of significance in terms of
size and proportions.
Populations of A. constricta constricta from
Stations 182 and 201 on Peleliu differ slightly (table
CXIV), but not significantly. In respect to height, "t"
= 1.5554; for diameter, "t" = 1.1474; for H/D ratio,
"t" = 1.4169; and for D/U ratio, "t" = 0.4803. On a
two-sided test, with 15 df, the largest figures have a
cumulative probability of between 10-20 per cent. A
great contrast is seen when different subspecies are
compared. A. c. constricta from Station 182 on Peleliu
and A. c. babelthuapi from Station 15 on Babelthuap,
with 11 df, are nearly identical in height ("t" =
0.2601); moderately distinctive in D/U ratio "t" =
1.8744, 2.5-5 per cent probability level with a one-sided
test); and very different in respect to diameter ("t" =
5.7576) and H/D ratio ("t" = 4.5130) - a probability
level of less than 0.05 per cent. A. c. constricta from
Station 201 on Peleliu and A. c. komakanensis from
Station 221 on Koror, with 8 df, are quite similar in
diameter ("t" = 0.7844), but very different in height
("t" = 3.4515), H/D ratio ("t" = 3.9886) and D/U
ratio ("t" = 6.6176) -- less than 0.5 per cent
probability level for a one-sided test. A. c. babelthuapi
and A. c. komakanensis, with 4 df, are very different in
diameter ("t" = 7.3874) and height ("t" = 3.8146),
both with a probability level of less than 1 per cent,
but quite similar in D/U ratio ("t" = 1.3665) and H/D
ratio ("t" = 0.2189).
The scatter diagrams in Figures 201 and 202
provide simple means for separation of doubtful
specimens. Plotting of the height and diameter will
segregate babelthuapi and komakanensis from the
nominate race (fig. 201). Separation of angaurana and
constricta constricta is most clearly shown by plotting
H/D and D/U ratios (fig. 202).
Aaadonta constricta constricta (Semper, 1874).
Figures 203a-c; 208d.
Endodonta constricta Semper, 1874, Reisen im Arch, der Philip-
pinen, (2), 3, p. 140 - Peleliu, Palau Islands.
Helix (Endodonta) constricta (Semper), Pfeiffer, 1876, Monog.
helic. viv., 7, p. 568; Tryon, 1887, Man. Conchol., (2), 3, p. 67.
Endodonta (Endodonta) constricta Semper, Pilsbry, 1893, op. cit.,
(2), 9, p. 26.
Diagnosis. — Shell a little larger than average, diameter 3.81-
4.27 mm. (mean 4.02 mm.), with 5l/s-6 moderately tightly coiled
whorls. Apex and spire markedly and evenly elevated, whorls
strongly rounded above protruding keel and prominent suprape-
ripheral sulcus, H/D ratio 0.530-0.635 (mean 0.570). Umbilicus open,
contained 4.91-6.63 times (mean 5.58) in the diameter. Apical whorls
1%, sculpture of 14-18 very fine, obscure spiral riblets with low radial
swellings near end. Remaining whorls with few growth wrinkles and
sculpture of fine radial riblets crossed by very fine, closely spaced
spiral riblets with a few scattered secondary spiral cords. Sutures
shallow, whorls strongly rounded below flattened shoulder, sides of
spire flat. Aperture ovate with rostrate margin, strongly rounded
above periphery. Parietal wall with 3 barriers, extending almost one-
quarter whorl, the lower two reduced in height and closer together,
rarely (one-fifth of time) with an accessory trace. Columellar barrier
low, very deeply recessed. Palatal barriers 5, the upper 2 reduced in
prominence, all extending about three-sixteenths of a whorl, only
upper palatal supraperipheral. All major barriers regularly beaded
above on posterior sections.
The smaller size, more strongly rounded whorls,
and 3 parietal barriers effectively separate A. con-
stricta from the larger A. irregularis. A kinlochi has a
flat spire and a deeply recessed columellar barrier,
while the much smaller A. fuscozonata and A.
pelewana have a tiny umbilicus and are much more
elevated. The nominate race from Peleliu is larger and
more depressed than A. c. babelthuapi from Babel-
thuap and Ngemelis (diameter 3.44-3.54 mm., H/D
ratio 0.625-0.682). A. c. komakanensis has the colu-
mellar barrier much more prominent and less recessed,
a narrower umbilicus (D/U ratio 6.79-8.00), and is
more elevated (H/D ratio 0.612-0.700).
Description (based on paratype). — Shell juvenile, with slightly
less than 5 whorls. Apex and spire markedly and evenly elevated, last
whorl not descending more rapidly, H/D ratio 0.575. Apical whorls
slightly less than 1%, sculpture of about 19 fine spiral riblets.
Postnuclear whorls with a lattice of coequal radials and spirals,
former often obscured by growth wrinkles. Sutures shallow, whorls
with flat shoulders, strongly rounded to supraperipheral sulcus.
Periphery protruded into a cordlike keel, subperipheral sulcus weak,
lower palatal wall somewhat flattened, sloping to strongly rounded
umbilical margin. Color faint yellow-white, with strong, regularly
spaced, reddish flammulations becoming narrow and zigzagged on
base, flaring inside umbilicus. Latter small, almost U-shaped, slightly
and regularly decoiling, contained 6.24 times in the diameter.
Aperture elongate-ovate, with rostrate periphery, inclined about 15°
from shell axis. Parietal barriers 3, with one accessory trace,
extending posteriorly more than one-quarter whorl: upper high, thin,
with sharp anterior descension, fine beads on posterior half; 2nd and
3rd parietals lower, looser together, with more gradual anterior
descension, beading on posterior two-thirds. Accessory trace a low
bladelike ridge located just below parietal-palatal margin. Colu-
mellar wall with single barrier, threadlike anteriorly, moderately
elevated posteriorly, only extending partway across thick columellar
callus. Palatal barriers 5, extending posteriorly three-sixteenths of a
whorl, upper 2 reduced in size: lower palatal basal in position, high,
twisted slightly upward in crossing basal callus, strongly beaded
above; 2nd and 3rd palatals with progressively more gradual anterior
descension, three very strong beads above on posterior two-thirds;
4th palatal subperipheral, greatly reduced in height, with three
slender elongated beads; 5th palatal supraperipheral, a low ridge
with three very faint elongated beads above. Height of paratype 2.01
mm., diameter 3.49 mm.
Lectotype. — Probably in Zoologisches Museum
der Humboldt-Universitat, Berlin.
Range. — Peleliu, Palau Islands.
Paratypes. - Peleliu, Palau Islands (FMNH 46245
ex Berlin Museum, Karl Semper).
Material. — Palau Islands (1 specimen, BPBM
106241): Peleliu, short distance from phosphate mine
(Stations 201, 203) and 300-400 yd. north at 35-200 ft.
elevation (52 specimens, BPBM 159938-43, BPBM
159989); Omurbrogol Mt. (Station 182), Asias village,
one-half to three-fourths mile inland at 300-400 ft.
elevation (27 specimens, BPBM 159423-7); 300 yd.
north of NKK Club (Station 196) in phosphate testing
ground at 50 ft. elevation (2 specimens, BPBM
159864); one-half to 1 mile north of Ngalkiok (Station
1
FIG. 203. a-c, Aaadonta constricta constricta (Semper). Peleliu. Palau Islands. Paratype. FMNH 46245 ex W. F. Webb. Zool. Mus. Berlin;
d-f. Aaadonta irregularis (Semper). Station 201. Peleliu. Palau Islands. BPBM 159937. Scale lines equal 1 mm. (MM).
475
476
SOLEM: ENDODONTOID LAND SNAILS
207) inland one-sixth to one-fifth mile at 5-10 ft.
elevation (1 specimen, BPBM 160046).
Remarks. — Probably a lectotype can be selected
from material in the Zoologisches Museum der
Humboldt-Universitat, Berlin. A subadult paratype
(FMNH 46245) has been described, but not selected as
lectotype. It is unusual only in having a small parietal
trace just below the parietal-palatal margin. This
lamellar trace was present in only about 20 per cent of
the specimens.
Of the 82 specimens collected by the Micronesian
Expedition, only 21 were adult.
Description of soft parts. — Foot and tail slender, elongated, not
tapering posteriorly, bluntly rounded behind, truncated anteriorly
with head projecting in front of foot. Sole smooth, undivided. Pedal
grooves rather high on side of foot, suprapedal weaker than pedal,
both uniting over tail, caudal horn absent, no middorsal groove
visible. Slime network finely reticulated, more obvious on tail than
head region. Ommatophores long, eyespot quite small and circular.
Gonopore located directly below right ommatophore, slightly above
and behind right rhinophore.
Body color light yellow-white in preservative, no darker
markings.
Mantle collar elongated, heavily glandularized, with glandular
extension marking areas of apertural barriers. Pneumostome a
simple opening at parietal-palatal angle, no special development of
mantle lobes. Anus opening just inside mantle collar at parietal-
palatal angle, a slightly diagonal slit, no special groove through
pneumostome visible.
Pallial region (fig. 199a) extending apically one-half whorl,
flattened length from pneumostome to base of kidney about 4.15
mm. Lung roof clear, without granulation. Kidney (K) about 2.1
mm. long, thick base curved, indented below by abuttment of
intestinal loop and spermatheca, posterior third reaching hindgut,
tapering forward past heart to narrow blunt apex. Ureter (KD) a
broad tube, passing apically along upper edge of kidney lobe, opening
at point where kidney reaches hindgut. Heart (H) about one-half
length of kidney, slightly angled in relation to hindgut, relatively
large in proportion. Principal pulmonary vein (HV) paralleling
hindgut, unbranched, fading out in area of glandular protrusions.
Hindgut (HG) reaches palatal-parietal margin about one-eighth
whorl above apex of pallial cavity, running forward without change
in diameter to anus.
Ovotestis (G) as in Endodonta fricki, imbedded in digestive
gland above apex of stomach, but not reaching to top of soft parts.
Palmately clavate clumps strung along single collecting tubule.
Hermaphroditic duct (GD) slender, hiehlv convoluted at first,
becoming expanded and straight along most of stomach length,
making a right-angle turn before inserting into carrefour (X) (fig.
199c). Albumen gland (GG) poorly preserved, outline indistinct, lying
above apex of pallial cavity next to intestinal loops and base of
stomach. Carrefour (X) receiving ducts from talon (GT) and
hermaphroditic duct (GD) at approximately right angles. Two
channels lead from carrefour into prostate and uterus, but the
available material did not allow accurate determination of the
channel patterns inside carrefour. Figure 199c indicates the probable
pattern through use of dotted lines. Duct of albumen gland opening
into head of uterus, slightly below point where clear separation of
uterine and prostatic channels can be observed. Carrefour itself a
semi-translucent ovoid sac. narrowing abruptly to prostate-uterine
heads. Channels obviously connect the talon and hermaphroditic
duct to the area from which the prostatic and uterine channels
depart, but the exact structure of the central area could not be
determined. Prostate (DG) a narrow tube arising from carrefour,
closely appressed to uterus. After first short section, two or three
rows of alveolar sacs insert into tube, at first partly hiding uterus,
then being partly hidden by uterus on lower section as they decrease
in size. Uterus (UT) in two sections, upper a large tube, expanded
after midsection to form a large bag that narrows just before
changing to free oviduct.
Vas deferens (VD) slender, paralleling free oviduct to peni-
oviducal angle, entering head of epiphallus through a pair of
pilasters into a small chamber flanked by pilasters (fig. 199d).
Epiphallus (E) little more than half length of penis, internally with
two narrow pilasters, rugose apically, leading into penis without
sharp differentiation of region. Penial retractor (PR) originating on
diaphragm just below apex of pallial cavity, inserting on looped part
of penial complex as a gradual fusion with the tissue and not as
direct insertion of a muscle band. Penis (P) compact, about 1.4 mm.
long, larger above and tapering anteriorly to junction with
spermatheca just before entering atrium. Epiphallic pilasters enter,
one expands and they merge (fig. 199d) forming a weak pocket, then
continue towards gonopore, gradually tapering. Two secondary
pilasters could be seen in a few specimens. Atrium (Y) a rather long
tube with 2-3 narrow pilasters inside.
Free oviduct (UV) much thicker than vas deferens, internally
with fine longitudinal pilasters, merging into atrium. Spermatheca
(S) entering base of penis, slender shaft passing up free oviduct and
prostate-uterus to the expanded head, which lies between anterior
end of albumen gland and apical end of kidney above apex of pallial
cavity and underneath anterior intestinal loop. Vagina (V) absent.
Free muscle system simple. Right ommatophoral retractor
passing through penioviducal angle, uniting with right rhinophoral
retractor about one-third of way to tail fan. Tentacular retractors
unite separately with tail fan well in front of point where buccal
retractors attach.
Buccal mass elongated, slender. Buccal retractors originating
where tail fan attaches to shell, inserting on bottom posterior edge of
buccal mass in a narrow band. Esophagus arising about midpoint of
buccal mass, very slender, extending above apex of pallial cavity.
Stomach taking less than one-quarter whorl to reach parietal-palatal
margin, extending a total of 1'4 whorls. For most of length occupying
outer wall as in Endodonta fricki. Intestinal looping as in E. fricki:
after leaving stomach it follows inner wall margin; loops up across
base of kidney and on top of spermathecal head; reflexes back for
about 1.7 mm., angling downwards; then curving up to parietal-
palatal margin and runs forward as hindgut, continuing anteriorly to
anus.
Digestive glands typical. Salivary glands uniting over esophagus
for posterior one-quarter.
Jaw not mounted successfully.
Radula partly fragmented during mounting. Central about 8ju
wide and 9ft long. Laterals 5-6 in number, marginals more than 10
with split cusps.
(Based on BPBM 159938, four examples, whole specimen
diameter 3.91 mm., with 5'/2 whorls.)
Aaadonta constricta babelthuapi, new subspecies.
Figure 204c-d.
Diagnosis. — Shell small, diameter 3.44-3.54 mm. (mean 3.47
mm.), with 5'/&-5'4 tightly coiled whorls. Apex and spire strongly and
evenly elevated, H/D ratio 0.625-0.682 (mean 0.647). Umbilicus
narrow, U-shaped, regularly and slightly decoiling, contained 5.77-
7.42 times (mean 6.50) in the diameter. Sculpture and color as in A.
c. constricta. Whorls quite strongly rounded after flat shelf from
suture, then dropping vertically to sharply defined supraperipheral
sulcus. Keel, base of shell, and aperture as in nominate subspecies.
Parietal and palatal barriers as in A. c. constricta with upper
parietal trace present in type. Columellar barrier usually absent.
Although the height of the shell is the same as in
A. c. constricta, the much smaller diameter results in a
higher H/D ratio and smaller D/U ratio. A. c.
FIG. 204. a-b, Aaadonta conatricta komakanensis, new subspecies. Station 221. Koror Island, Palau Islands. Holotype. BPBM 158862; c-d,
A. c. babelthuapi, new subspecies. Station 15, Babelthuap Island, Palau Islands. Holotype. BPBM 160524; e-f, A. angaurana, new subspecies.
Station 175, Angaur Island, Palau Islands. Holotype. BPBM 158310. Scale lines equal 1 mm. (SG).
477
478
SOLEM: ENDODONTOID LAND SNAILS
babelthuapi also has lost the columellar barrier, which
is weakly developed in A. c. constricta and strongly
developed in A. c. komakanensis.
Description. — Shell small with 5'/8 tightly coiled whorls. Apex
and spire strongly and evenly elevated, whorls acutely rounded
above after flat shelf to suture, a protruded peripheral keel and a
deep supraperipheral sulcus, H/D ratio 0.625. Apical whorls 1%,
sculpture partially eroded, but traces of fine spiral riblets remaining.
Lower whorls with irregular growth wrinkles somewhat masking the
typical Aaadonta microsculpture. Sutures shallow, whorls flattened
at shoulder, strongly rounded laterally, then dropping vertically to
deep supraperipheral sulcus. Umbilicus open, U-shaped, slightly
dec-oiling, a little constricted by umbilical lip, contained 5.77 times in
the diameter. Aperture compressed ovate with birostrate upper
margin, inclined about 15° from the shell axis. Parietal barriers 3,
extending one-quarter whorl, regularly beaded above on posterior
five-eighths, lower 2 crowded and reduced in height. Single parietal
trace just below parietal-palatal margin. Columellar barrier absent.
Palatal barriers 5, extending three-sixteenths of a whorl, regularly
beaded above on posterior two-thirds, lower 3 reaching margin and
equal in height, upper 2 recessed and reduced in height with very
elongate, fine beading, 5th supraperipheral. Height of holotype 2.15
mm., diameter 3.44 mm.
Holotype. — Palau Islands: Babelthuap, Station
15, Adelulu Hill, Airai-Mura, 30 m. inland at 20-40 m.
elevation. Collected by S. Ito on April 21, 1936. BPBM
160524.
Paratypes. - BPBM 160524, BPBM 160525.
Material. — Babelthuap: (Station 15) Adelulu
Hill, Airai-Mura, 30 m. inland at 20-40 m. elevation (3
specimens, BPBM 160524, BPBM 160525). Ngemelis:
Hillside (Station 210) at 2-35 ft. elevation (1 specimen,
BPBM 159232).
Remarks. — A single shell from Ngemelis (height
2.25 mm., diameter 3.54 mm., H/D ratio 0.635, whorls
5'/4, D/U ratio 6.30) agrees closely with the Babelthuap
types in size and proportions and is included under
this subspecific designation, despite having a rather
prominent columellar barrier. When more material is
available from Ngemelis, separation of these popu-
lations may be warranted.
Three of the four shells were adult, a much higher
ratio than was found in most other Aaadonta.
Description of soft parts. — Two animals extracted from the
shells were fragmented. Apical pallial organs and genitalia missing.
Penial structures as in A. c. constricta, with exact pilaster pattern
duplicated. No significant differences noted in anterior parts of
animal from those of A. constricta constricta. Jaw very delicate, of
separate plates connected by a thin membrane.
(Based on BPBM 160524.)
Aaadonta constricta komakanensis, new sub-
species. Figure 204a-b.
Diagnosis. - Shell larger than average, diameter 3.97-4.27 mm.
(mean 4.12 mm.), with 5'2-57/8 tightly coiled whorls. Apex and spire
strongly and evenly elevated, last whorl descending more rapidly,
H/D ratio 0.612-0.700 (mean 0.660). Umbilicus narrow, U-shaped, not
decoiling, contained 6.79-8.00 times (mean 7.47) in the diameter.
Sculpture as in A. c. constricta. Suture shallow, whorls sloping to
strongly rounded shoulder, angling into prominent supraperipheral
sulcus. Periphery protruded into prominent keel, below which is a
weak sulcus. Aperture ovate, broadly rounded below periphery.
Parietal and palatal barriers as in A. c. constricta, except for greater
size reduction of 3rd parietal. Columellar barrier prominent, crossing
top of columellar callus.
The larger size, prominent columellar, and re-
duced 3rd parietal barrier separate A. c. komakanensis
from A. c. babelthuapi. A. c. constricta differs in its
much lower spire (mean H/D ratio 0.570) and wider
umbilicus (mean D/U ratio 5.58).
Description. — Shell larger than average with 5% tightly coiled
whorls. Apex and spire strongly and evenly elevated, whorls
moderately rounded above flat sutural shelf with protruded keel and
prominent supraperipheral sulcus, last whorl descending more
rapidly, H/D ratio 0.663. Apical whorls 1%, sculpture of about 16 fine
spiral riblets with faint traces of radial undulations at end.
Remaining whorls with sculpture of growth wrinkles and a
microsculpture of fine radial riblets with finer spiral ribs and
secondary sculpture of rather widely spaced spiral cords. Sutures
shallow, whorls first flattened, then moderately rounded above
peripheral sulcus, keel protruded, base of shell evenly rounded, not
compressed, to strongly rounded umbilical margin. Umbilicus
narrow, slightly constricted by coiling of last whorl and reflection of
umbilical lip, U-shaped, contained 7.35 times in the diameter. Color
light yellowish-white with irregular reddish, flammulations. Aperture
with rostrate periphery, ovate, inclined about 15° from the shell axis.
Parietal barriers 3, extending one-quarter whorl, posterior two-thirds
regularly beaded above, 2nd and 3rd parietals crowded, with 3rd
parietal greatly reduced in height. Columellar barrier parallel to
plane of coiling, a low but prominent ridge, slightly recessed within
aperture. Palatal barriers 5, extending three-sixteenths of a whorl,
lower 3 nearly reaching margin and equal in height, upper 2 reduced
in height, recessed, with much finer beading. Lower 3 palatals
strongly beaded on posterior parts. Height of holotype 2.73 mm.,
diameter 4.11 mm.
Holotype. — Palau Islands: Koror, Station 221,
southeast end of small peninsula near Komakan at 5-
90 ft. elevation. Collected by Yoshio Kondo on May
11, 1936. BPBM 158862.
Range. — Koror, Palau Islands.
Paratypes. - BPBM 158862-9.
Material. — Koror: (Station 221) southeast end of
small peninsula near Komakan at 5-90 ft. elevation (42
specimens, same as list of paratypes).
Remarks. — In slightly subadult shells, such as
BPBM 158863, the descension of the body whorl is
only slightly evident, and in metaneanic individuals is
absent. The evenly rounded lower palatal wall
contrasts with the normally compressed region in
other Aaadonta. Although absent in the holotype, an
upper parietal trace was present in nearly every
specimen examined. The much greater reduction of the
3rd parietal seems to be correlated with the much
greater development of the columellar, since in the
other subspecies, where the columellar barrier is
absent, or reduced, the 3rd parietal is proportionately
nearer the 2nd in size.
Only four of the 42 specimens were adult.
Description of soft parts. — Inspection of several torn
individuals revealed no differences in terminal structure from those
observed in A. c. constricta. The preservation was not very good, so
that pilaster patterns were indistinct. Jaw and radula not mounted.
(Based on BPBM 158862.)
SYSTEMATIC REVIEW
479
,-v
BOO
ISC
650
60!'
AAADONTA
^k pelewana
•A- fuscozonata depressa
fuscozonata fuscozonata
J_
J
1C
20
25
35
••>
45
51
30
D/U Ratio
FIG. 205. Proportionate differences between Aaadonta pelewana
and A. fuscozonata.
Aaadonta fuscozonata (Beddome, 1889)
This very small species is most likely to be
confused with A. pelewana. The latter differs most
obviously in having a more widely open umbilicus
(D/U ratio 6.68-10.6) and an obtusely rounded pe-
riphery (fig. 205). In fuscozonata the umbilicus is
minute (D/U ratio more than 15) and the periphery is
distinctly rostrate. There are also differences in
barriers. A. fuscozonata has the beading on the 1st
parietal weaker and more widely spaced than on the
2nd and 3rd and there is a distinct, deeply recessed 2nd
columellar barrier; A. pelewana usually has the
parietal with equal-sized beading and there is no 2nd
columellar.
I recognize two subspecies:
A. fuscozonata fuscozonata (Beddome, 1889) from
Koror Island, which has 3 major palatal barriers
extending nearly one-half whorl, the 2nd distinctly
smaller, a higher spire (mean H/D ratio 0.767) and
minute umbilicus (mean D/U ratio 27.7); and
A. fuscozonata depressa, new subspecies from
Peleliu Island, which has 5 palatal barriers extending
less than one-quarter whorl, the lower 3 coequal in
size, a lower spire (mean H/D ratio 0.702) and a
slightly more open umbilicus (mean D/U ratio 16.8).
If collection of additional material confirms these
differences in palatal barriers as constant for all
Peleliu shells, then depressa should be considered a
distinct species. Since only three specimens were
available, I preferred the conservative course of
recognition at the subspecific level.
Aaadonta fuscozonata fuscozonata (Beddome,
1889). Figure 206a-c.
Helix (Endodonta) fusco-zonata Beddome, 1889. Proc. Zool. Soc.
London, 1889, p. 116, pi. 12, figs. 12,a-c - Koror. Palau Islands.
Patula (Endodonta) fuscozonata (Beddome), Pilsbry, 1892, Man.
Conchol., (2), 8, p. 83, pi. 30, figs. 39-42.
Endodonta (Endodonta) fuscozonata Beddome, Pilsbry, 1893, op.
cit., (2), 9, p. 26.
Diagnosis. — Shell very small, diameter 2.68-3.15 mm. (mean
2.93 mm.), with 5V8-6'/2 tightly coiled whorls. Apex and spire very
strongly elevated, slightly rounded above, H/D ratio 0.662-0.820
(mean 0.767). Umbilicus minutely perforate, contained 17.0-46.5
times (mean 27.7) in the diameter. Apical whorls 1%, sculpture of
fine, close-set spiral riblets and weak radial swellings. Remaining
whorls with irregular radial ribs and growth wrinkles, plus a
microsculpture of a few, widely spaced radial and much finer spiral
riblets. Sutures shallow, whorls gently rounded down to shallow
supraperipheral sulcus and weakly protruded keel. Subperipheral
sulcus equal in size, base of shell rounded to umbilical margin.
Aperture ovate with slightly rostrate periphery and expanded basal
lip. Parietal barriers 3, extending posteriorly beyond line of vision,
lower reduced in prominence from 2nd and crowded more closely to
it, all with small, widely spaced beading on posterior portion that is
much more widely spaced on 1st barrier. Columellar barrier a very
prominent, rounded ridge lying parallel to plane of coiling, then
slanted downward across columellar callus, usually with a low broad
upper accessory barrier. Major palatal barriers 3, extending beyond
line of vision, with widely spaced beads above, 2nd palatal smaller
than 1st and 3rd, occasionally with one or two upper accessory
traces.
The much higher spire, barely perforate umbilicus,
and 3 long palatals separate the nominate form of A.
fuscozonata from the Peleliu Island subspecies of A. f.
depressa, which has 5 short (less than one-quarter
whorl) palatals, a more depressed spire, and a slightly
more open umbilicus. A. pelewana has (usually) 4
palatals and a moderately open umbilicus. Other
species of Aaadonta are much larger and less elevated
with wider umbilici.
Description. — Shell small with 5% tightly coiled whorls. Apex
and spire very strongly and evenly elevated, a little rounded above,
last whorl not descending more rapidly, H/D ratio 0.662. Apical
whorls l'/2, sculpture of very fine, crowded spiral riblets, partially
eroded. Remaining whorls with low, irregular, close-set radial growth
striae, slightly protractive, of varying strength and spacing. Micro-
sculpture, where visible, of fine radial riblets crossed by much finer
and more crowded spiral riblets. Sutures shallow, whorls almost
evenly rounded above with prominent supra- and subperipheral sulci,
a threadlike protruding keel and evenly rounded basal margin. Color
light yellowish-white with broad, relatively regularly spaced, reddish
flammulations becoming narrower, zigzag and fainter on base of
shell. Umbilicus minute, not decoiling, contained 19.4 times in the
diameter. Aperture elongately ovate with weakly beaked periphery,
evenly rounded above and below, inclined about 10° from the shell
axis. Parietal harriers 3, extending posteriorly beyond line of vision:
upper thin, high, bladelike, sharply descending anteriorly with a few
weak, elevated, regularly and widely spaced beads above; 2nd
parietal slightly lower with more rounded, expanded and closely set
beading; lower parietal a threadlike ridge with low, crowded beading
above. Parietals 2 and 3 spaced closer together than 1 and 2, all
beads minutely barbed. Columellar wall with moderately thick callus
extending onto basal lip. Columellar barriers 2: upper a low, recessed,
broad, threadlike ridge becoming higher posteriorly; second a
prominent lamellar ridge extending across callus to lip edge and
slanting slightly downward. Both columellars parallel to plane of
coiling posteriorly. Palatal barriers 3, extending beyond line of
vision: lower palatal basal in position, a high, slightly twisted lamella
reaching lip edge with very sharp anterior descension, faintly beaded
above posteriorly; 2nd palatal a low, threadlike ridge, more strongly
beaded above, very slightly recessed from lip margin; 3rd palatal a
moderately high, lamellate ridge with quite prominent swollen beads
above, gradually descending anteriorly and reaching almost to lip
edge. Height of holotype 1.89 mm., diameter 2.86 mm.
a
""
abc
FIG. 206. a-c, Aaadonta fuscozonata fuscozonata (Beddome). Station 219, Koror Island, Palau Islands. BPBM 158778. d-f, A. f.
depressa, new subspecies. Station 203, Peleliu, Palau Islands. Holotype. BPBM 159990. Scale lines equal 1 mm. (a-c, MM; d-f, SG).
480
SYSTEMATIC REVIEW
481
Holotype. — Palau Islands: Koror. Collected by
Hungerford. BMNH 91.3.17.1042.
Range. — Koror, Palau Islands.
Material. — Koror (1 specimen, BMNH
91.3.1.7.1042): Komakan (Station 222) at 100-200 ft.
elevation (3 specimens, BPBM 154848-9); Komakan
(Station 221) at 5-90 ft. elevation (12 specimens,
BPBM 158870-3); Komakan (Station 219) at 75 ft.
elevation (20 specimens, BPBM 158778-82).
Remarks. — The holotype is a very depressed,
rather small specimen that has particularly strong
development of the second columellar barrier. No
specimens collected in recent years exactly match its
characters. The next most depressed specimen had a
H/D ratio of 0.706 and the mean for that set (table
CXIV) was 0.774. Although the type of fuscozonata is
within the shape range of A. f. depressa, the difference
in palatal barriers is the significant factor separating
the two subspecies.
As shown in Figure 206c, fresh specimens often
reveal how far the palatal barriers extend posteriorly
by the thick bases being visible through the shell in
strong lighting. In A. f. fuscozonata they extend about
one-half whorl, more than twice the distance the
palatals extend in A. f. depressa.
Description of soft parts. — Foot about 2.3 mm. long, very
slender, slightly tapering at tail, rounded behind, truncate anteriorly.
Sole and pedal grooves typical, caudal horn and middorsal groove
absent. Slime network very faint. Head slightly protruding in front
of foot. Ommatophores long, eyespot small, circular. Gonopore a
narrow groove below right ommatophore, behind and a little above
right rhinophore.
Body color yellow-white in preservative, no darker markings.
Mantle collar (MC) thin, without obvious glandular extensions
onto pallial roof. Pneumostome typical, no mantle lobes developed.
Anus (A) in normal position.
Pallial region (fig. 199f) extending about 1% whorls apically,
flattened length about 4.9-5.3 mm. Lung roof clear, without
granulations. Kidney (K) narrow, about 1.7 mm. long, base indented
by spermathecal head and kidney loop, part abutting on hindgut.
Ureter (KD) typical, opening near junction of kidney and hindgut
after slight reflection apically. Heart (H) slightly less than half
length of kidney, paralleling hindgut. Principal pulmonary vein (HV)
simple, unbranched, could not be traced to mantle collar. Hindgut
(HG) reaching parietal-palatal margin one-quarter whorl above apex
of pallial cavity, diameter unchanged to anus.
Ovotestis (G) as in A. constricta. Hermaphroditic duct (GD)
highly convoluted at first, slightly iridescent, last section straight
before entering carrefour. Albumen gland (GG) typical, extending
nearly to last intestinal loop, lying above pallial cavity apex. Head of
talon (GT) enlarged, buried in albumen gland, shaft slender, rather
long. Carrefour (X) less enlarged than in A. constricta. Prostate
(DG) short, 2-3 rows of acini opening into slender duct. Weakly
bound to uterus. Shaft of spermatheca bound to duct of prostate to
just above acinar portion. Uterus (UT) less clearly differentiated into
two sections than usual, very thin-walled.
Vas deferens (VD) typical, duct much larger than shaft of
spermatheca (fig. 199e). Epiphallus (E) with same entry seen in A.
constricta. two large pilasters continuing into penis. Penial retractor
(PR) arising from diaphragm well below apex of pallial cavity,
inserting on penis-epiphallus well below loop area. Penis (P) about
1.6-1.8 mm. long, with two pilasters, one splitting to form a pocket as
in A. kinlochi, not tapering as much to atrium junction. Atrium (Y)
long, weak pilasters inside.
Free oviduct (UV) not sharply differentiated from uterus,
tapering gradually to atrium, very thin-walled. Spermatheca (S) as
in A. constricta, inserting on base of penis. Vagina (V) absent.
Free muscle system typical.
Digestive system with stomach extending l'/4 whorls apically
from pallial cavity apex. Otherwise typical.
(Based on BPBM 158778, four examples, whole specimen
diameter 2.76 mm. with 6+ whorls.)
Aaadonta fuscozonata depressa, new subspecies.
Figure 206d-f.
Diagnosis. - Shell quite small, diameter 2.95-3.31 mm. (mean
3.15 mm.), with 5'/2-55/8 tightly coiled whorls. Apex and spire quite
strongly elevated, slightly rounded above, H/D ratio 0.698-0.707
(mean 0.702). Umbilicus minute, not decoiling, contained 16-17.8
times (mean 16.8) in the diameter. Sculpture, color and whorl
contours as in A. f. fuscozonata. Parietal and columellar barriers also
as in nominate race. Palatal barriers 5, extending three-sixteenths of
a whorl, only upper supraperipheral: lower 3 coequal in height,
reaching apertural margin, 3rd with more gradual anterior descen-
sion; upper 2 prominent and bladelike, reduced in height from lower
3. Beading equal on lower 2 palatals; reduced and more widely
spaced on 3rd; greatly reduced on 4th; and apparently absent on 5th
barrier.
The presence of 5 shorter palatal barriers and
more depressed shape separate A. f. depressa from the
nominate subspecies. A. pelewana differs in being
distinctly smaller (mean diameter 2.75 mm.) and has a
much more open umbilicus (mean D/U ratio 8.18) in
addition to the altered palatal barriers.
Description. — Shell small with 5'/2 tightly coiled whorls. Apex
and spire evenly elevated, whorls strongly rounded above prominent
threadlike periphery with shallow supraperipheral sulcus, H/D ratio
0.700. Embryonic whorls 1%, sculpture partially eroded with traces of
numerous, very fine spiral ribs remaining. Remaining whorls with
irregular riblike growth wrinkles and a microsculpture of fine radial
riblets and relatively more crowded spiral riblets. Sutures shallow,
whorls moderately shouldered below, then sloping down to distinct
supraperipheral sulcus. Umbilicus very narrowly open, not decoiling,
partly covered by reflexion of columellar lip, contained 16.67 times in
the diameter. Color light yellow-brown with relatively prominent,
irregular, reddish flammulations, becoming wider and sinuated on
base of shell. Aperture ovate with weakly rostrate periphery, inclined
about 10° from the shell axis. Parietal barriers 3, extending beyond
the line of vision, regularly beaded above after anterior sixteenth
whorl, lower parietal markedly reduced in height. Beading on upper
parietal finer and more widely spaced. Columellar barriers 2, upper
deeply recessed and greatly reduced in prominence, lower a high
lamella, slanting downward across columellar callus. Palatal barriers
5, extending three-sixteenths of a whorl, lower 3 equal in size and
reaching lip margin, upper 2 reduced in prominence and slightly
recessed. Lower 2 palatals with crowded, large beads; 3rd palatal
with three widely spaced, finer beads; 4th palatal much lower with
only traces of beading remaining; 5th palatal a bladelike ridge
without trace of beading, located just above supraperipheral sulcus.
Height of holotype 2.30 mm., diameter 3.29 mm.
Holotype. -- Palau Islands: Peleliu, Station 203,
300-400 yd. north of phosphate mine at 35-200 ft.
elevation. Collected by Yoshio Kondo on April 29,
1936. BPBM 159990.
Range. — Peleliu, Palau Islands.
Paratypes. - BPBM 159990, BPBM 159600.
482
SOLEM: ENDODONTOID LAND SNAILS
FIG. 207. a-c. Aaadonta pelewana new species. Palau Islands.
Holotype. BM(NH) 91.3.17.443. Scale line equals 1 mm. (SG).
Material. - Peleliu: (Station 203) 300-400 yd.
north of phosphate mine at 35-200 ft. elevation (2
specimens, BPBM 159990); Road to Asias (Station
187) at 80 ft. elevation (1 specimen, BPBM 159600).
Remarks. — All three specimens were adult. The
differences from A. f. fuscozonata outlined in the
diagnosis are large enough to indicate specific level
differentiation, if collection of more material from
Peleliu confirms that thev are constant. Subspecific
status is employed here in view of the limited material
available.
Aaadonta pelewana, new species. Figure 207a-c.
Diagnosis. — Shell minute for genus, diameter 2.56-2.88 mm.
(mean 2.75 mm.), with 5-5% tightly coiled whorls. Apex and spire
quite strongly and evenly elevated, a little rounded on top, H/D
ratio 0.628-0.704 (mean 0.682). Umbilicus very small, last whorl
decoiling noticeably, contained 6.68-10.6 times (mean 8.18) in the
diameter. Sculpture and color as in A. f. fuscozonata. Sutures
impressed, whorls strongly rounded above, sloping down to very faint
supraperipheral sulcus just above obtusely rounded periphery. Lower
palatal wall evenly rounded to expanded basal-columellar margin.
Parietal barriers 3, upper 2 coequal, 3rd distinctly reduced in size. All
usually strongly beaded above, occasionally upper with more widely
spaced beading. Columellar barrier high, thick, rounded above,
slanting diagonally downward while crossing columellar-basal callus.
Palatal barriers 3 (33 per cent) or 4 (67 per cent) plus one or two
accessory traces, extending nearly one-quarter whorl: 1st and 3rd
equal in size, with large bulbous beads above; 2nd (when present)
lower and narrower with finer beading; upper slightly subperipheral,
a low ridge with prominent beading. Usually a slightly suprape-
ripheral accessory threadlike trace present, occasionally a weak
thread present between 3rd and 4th palatals.
The obtusely rounded, not rostrate, periphery and
minute size immediately separate A. pelewana from
the other Aaadonta. A. fuscozonata is most similar,
but has a slightly rostrate periphery (fig. 206b, e) and
a much narrower umbilicus (D/U ratio 16-46.5).
Description. — Shell minute for genus, with a trifle more than
5% tightly coiled whorls. Apex and spire strongly elevated, a little
rounded above, last whorl descending only a trifle more rapidly, H/D
ratio 0.701. Apical whorls 1%, sculpture of about 18 fine spiral ribs
with crowded, barely visible radial swellings. Postnuclear whorls with
irregular growth wrinkles, plus a microsculpture of fine radial and
much finer spiral riblets. A secondary microsculpture of fine spiral
cords clearly visible on many parts of shell. Sutures well impressed,
whorls flatly sloping down to extremely weak supraperipheral sulcus.
Periphery obtusely rounded, not protruded, lower palatal wall evenly
rounded, a little compressed laterally. Basal margin strongly rounded
into umbilicus. Umbilicus narrow, U-shaped, last whorl decoiling a
little more rapidly, only slightly covered by reflection of columellar
lip, contained 7.91 times in the diameter. Aperture elongatelv-ovate,
slightly compressed laterally below periphery, inclined about 5° from
shell axis. Parietal barriers 3, extending posteriorly beyond line of
vision, with large swollen beads, slightly more widely spaced on
upper parietal, after smooth anterior portion: upper parietal very
high and bladelike, with gradual anterior descension, beads clearly
separated; 2nd equal in height, with sharper anterior descension,
beading more closely spaced; 3rd situated closer to 2nd than 2nd is
to 1st, about half the height, beading not separated by smooth area.
Columellar barrier a high rounded ridge, posteriorly lying parallel to
plane of coiling, anteriorly slanting diagonally downward across
columellar callus, with blunted descension almost to lip edge.
Palatals 4, extending one-quarter whorl, with two accessory traces:
1st palatal a thick high ridge with narrow, widely spaced beading,
sharp anterior descension; 2nd palatal greatly reduced in height.
SYSTEMATIC REVIEW
483
beading similar but proportionately smaller; 3rd palatal equal in
height to 1st. beading large and separated, with more gradual
anterior descension; 4th palatal slightly subperipheral, lower than
3rd, beading prominent, with gradual anterior descension. A very fine
accessory trace located between 3rd and 4th palatal; second trace
slightly supraperipheral with faint trace of beading. An elongate
bump located just above 4th palatal, a weaker bump just below.
Basal and lower palatal lip with rather thick callus. Height of
holotype 2.01 mm., diameter 2.86 mm.
Holotype. - Palau Islands. BMNH 91.3.17.443, ex
Hungerford, Gibbons collections.
Range. — Unknown, but certainly on one of the
Palau Islands.
Paratypes. - Palau Islands (BMNH 91.3.17.444,
FMNH 147277).
Material. — Koror (5 specimens, SMF 165429 ex
Moellendorff); Peleliu (2 specimens, Brussels ex Daut-
zenberg, Geret, Ancey, John H. Thomson).
Remarks. — Although no exact locality is known
for this species, its minute size and very distinctive
form merit nomenclatural recognition. The Natur-
Museum Senckenberg and Brussels specimens were
not directly utilized in drawing up the description and
diagnosis, so they are not considered paratypes. Both
island records are considered suspect, particularly in
view of the many hands through which the specimens
passed. I suspect Angaur or Babelthuap might be the
correct locality.
The obtusely rounded, not rostrate, periphery and
impressed sutures are unique among Aaadonta. In
having the 2nd palatal barrier reduced (or absent) A.
pelewana is more similar to A. f. fuscozonata than A.
f. depressa where the 2nd palatal is equal in size to the
1st and 3rd. As in depressa, the palatals extend
posteriorly less than one-quarter whorl.
Aaadonta irregularis (Semper, 1874). Figure
203d-f.
Endodonta irregularis Semper, 1874, Reisen im Arch, der
Philippinen, (2), 3, p. 141 - Peleliu, Palau Islands.
Helix (Endodonta) irregularis (Semper), Pfeiffer, 1876, Monog.
helic. viv., 7, p. 568; Tryon, 1887, Man. Conchol., (2), 3, p. 67.
Endodonta (Endodonta) irregularis Semper, Pilsbry, 1893, op. cit.,
(2), 9, p. 26.
Diagnosis. — Shell large, diameter 4.64-5.60 mm. (mean 5.10),
with SMi^'/s rather loosely coiled whorls. Apex and spire markedly
and evenly elevated, H/D ratio 0.541-0.666 (mean 0.589). Umbilicus
V-shaped, open, regularly decoiling. contained 4.30-7.15 times (mean
5.57) in the diameter. Apical whorls 1%, sculpture of 18-22 very fine,
crowded spiral riblets. with weak radial swellings on last portion.
Remaining whorls with a combination of irregularly spaced growth
wrinkles and a lattice of fine radial riblets with finer, more closely
spaced spiral riblets. A secondary microsculpture of more widely
spaced, finer spiral cords visible near periphery. Sutures shallow,
whorls only slightly rounded with prominent sub- and supraperipher-
al sulci, keel rounded and markedly protruded. Sides of spire flat,
slightly rounded above. Aperture ovate with rostrate periphery,
inclined about 10° from shell axis. Parietal wall with 2 prominent
barriers, extending posteriorly beyond line of vision, lower about
two-thirds height of upper, one-third of time with lower accessory
trace. Columellar wall with a single deeply recessed barrier, parallel
to shell axis, high and rounded posteriorly, but greatly reduced
anteriorly and not reaching across columellar callus. Palatal barriers
3, 1 supraperipheral, 2 subperipheral with two (67 per cent) or three
(33 per cent) accessory traces located between upper two palatals.
Major parietal and lower palatal barriers evenly beaded above,
beading less prominent than in other Aaadonta.
The presence of only 2 major parietals and 2
subperipheral palatal barriers immediately separates
A. irregularis from the smaller (diameter 3.44-4.27) A.
constricta with its 3 major parietals and 5 palatals. A.
kinlochi does not have the spire elevated, while the
similarly shaped A. angaurana is much smaller
(diameter 3.58-4.21 mm.), has 3 major subperipheral
palatals and 3 parietals. The minute (diameter 2.56-
3.31), very high spired (H/D ratio 0.628-0.820) A.
fuscozonata and A. pelewana cannot be confused with
irregularis.
Range. — Peleliu, Palau Islands.
Material. -- Peleliu: short distance from
phosphate mine (Stations 201, 203) and 300-400 yd.
toward the north at 35-200 ft. elevation (4 specimens,
BPBM 159937, BPBM 159987-8); Omurbrogol Mt.
(Station 182) Asias village, one-half to three-quarters
mile inland at 300-400 ft. elevation (2 specimens,
BPBM 159428); (Station 188) nearly 2 miles from club
after passing swamp at 75 ft. elevation (1 specimen,
BPBM 159633).
Remarks. — No type specimens could be located.
Since Semper's original description mentions six big
barriers, a major diameter of 5.5 mm., elevated spire,
and six whorls, no question of identification arises.
Possibly potential lectotype specimens are preserved in
the Zoologisches Museum der Humboldt-Universitat,
Berlin, but this collection was not seen. No selection of
a lectotype has been attempted. A more detailed
diagnosis is presented in the absence of a type
description.
Six of the seven specimens collected by the Bishop
Museum Micronesian Expedition were adult. In view
of the high percentage of juveniles in most other
species of Aaadonta (table CXII) this is quite
surprising. If it were not for the different position of
the major barriers and obviously flatter whorls,
irregularis might be mistaken as a gerontic form of
constricta. At three of the four stations where
irregularis was collected (Station 182, 201, 203)
constricta also occurred. The single exception, Station
188, had only a single specimen of irregularis taken.
No other endodontid was found there.
In shape of the whorls and spire, A. angaurana is
almost identical and probably is the closest relative.
Aaadonta angaurana, new species. Figure 204e-f.
Diagnosis. — Shell slightly larger than average, diameter 3.58-
4.21 mm. (mean 3.92 mm.), with 5%-6'/8 normally coiled whorls. Apex
and spire evenly elevated, rather low, rounded above, H/D ratio
0.471-0.565 (mean 0.511). Umbilicus widely open, U-shaped, slightly
and regularly decoiling, contained 3.83-4.70 times (mean 4.35) in the
diameter. Sculpture of apical and postnuclear whorls typical. Sutures
shallow, whorls flat to slightly rounded down to prominent
484
SOLEM: ENDODONTOID LAND SNAILS
supraperipheral sulcus. Periphery strongly protruded into rostrate
keel, with weak subperipheral sulcus. Aperture suhrectangular,
strongly compressed laterally below periphery, inclined about 15°
from shell axis. Parietal barriers 3, lower 2 reduced in height.
Columellar barrier a low bladelike ridge deeply recessed in aperture.
Palatal barriers 4, upper supraperipheral and greatly reduced in
height, lower 3 basal to subperipheral, 1st and 3rd distinctly lower
than 2nd. Parietal and palatal barriers beaded posteriorly.
Most closely resembling A. irregularis, the
possession of 3 major subperipheral palatals, 3 major
parietals, and the smaller size at once separate A.
angaurana. A. constricta is higher with a narrower
umbilicus and much more strongly rounded whorls. A.
fuscozonata and A. pelewana are much smaller and
higher, while A. kinlochi is immediately separable by
its flat spire and large size.
Description. — Shell smaller than average, with slightly less than
5'4 normally coiled whorls. Apex and spire markedly and evenly
elevated, very slightly rounded above, last whorl descending more
rapidly, H/D ratio 0.451. Apical whorls l'/2, sculpture mainly eroded,
traces of fine spiral ribbing remaining. Postnuclear whorls with
irregular growth wrinkles and fine radial riblets with a lattice of finer
and more crowded spiral riblets. Sutures shallow, whorls flatly
sloping to broad and shallow supraperipheral sulcus. Periphery
protruded into rostrate keel, a very weak subperipheral sulcus visible,
lower palatal margin flattened to strongly shouldered umbilical
margin. All color leached from shell except for a few faint, reddish
markings on body whorl. Umbilicus wide, U-shaped, slightly and
regularly decoiling, contained 3.98 times in the diameter. Aperture
subquadrangular, with weakly rostrate periphery, flattened laterally
above and below periphery, inclined about 10° from the shell axis.
Parietal barriers 3, extending posteriorly more than one-quarter
whorl: upper high, thin, bladelike. with sharp anterior descension,
edge broken on anterior two-thirds, beaded posteriorly; 2nd slightly
lower, more gradual anterior descension, broken off above anteriorly,
beaded posteriorly; 3rd a little lower, anterior end broken off,
strongly and closely beaded above. Columellar barrier a low,
bladelike ridge parallel to plane of coiling, deeply recessed within
aperture. Palatal barriers 4, extending posteriorly three-sixteenths of
a whorl, upper supraperipheral and greatly reduced in size: lower
basal in position, a high, bladelike lamellar ridge with gradual
anterior descension, prominently beaded on posterior two-thirds,
lying opposite lower parietal, distinctly lower than next 2 barriers;
2nd and 3rd palatals almost equal in height, lying opposite upper 2
parietals, strongly beaded above, 3rd lower and with more gradual
anterior descension than 2nd; 4th palatal supraperipheral, a low V-
shaped ridge only weakly beaded above and moderately deeply
recessed. Height of holotype 1.65 mm., diameter 3.62 mm.
Holotype. — Palau Islands: Angaur, Station 175,
north of shrine at edge of guano pit at 75-100 ft.
elevation. Collected by Kiyoko and Yoshio Kondo on
April 18, 1936. BPBM 158310.
Range. — Angaur Island, Palau Islands.
Paratypes. - BPBM 158310.
Material. — Angaur: (Station 175) north of shrine
at edge of guano pit at 75-100 ft. elevation (128
specimens, BPBM 158310, BPBM 158311, BPBM
158264).
Remarks. — The type is a very depressed, slightly
subadult specimen that was not included among the
measured set (table CXIV). It was selected as holotype
because of its excellent preservation. No living materi-
al was obtained and all the specimens were quite worn
and heavily dirt encrusted. Only 14 examples were of
adult size.
The form and general shape of A. angaurana is
very similar to that of A. irregularis. The latter (table
CXI) is distinctly larger (mean diameter 5.10 mm.),
higher (mean H/D ratio 0.589), and has only 3 major
palatal barriers. The size and general appearance of A.
angaurana are quite similar to those of A. c.
constricta, although the differences in whorl contour
and presence of 5 palatal barriers in the latter should
be sufficient for identification. Plotting of the H/D
ratio against the D/U ratio (fig. 202) provides
complete separation of available material. Size and
proportion differences between A. c. constricta from
Station 182 and A. angaurana (table CXIV) are
insignificant in respect to diameter ("t" = 0.7609 with
23 df), but very significant for height ("t" = 4.0817),
H/D ratio ("t" = 4.4346) and D/U ratio ("t" = 7.4420)
— the last three all being well within the 5 per cent
probability level.
Aaadonta kinlochi, new species,
a-c.
Figures 200; 208
Diagnosis. — Shell large, diameter 4.27-5.03 mm. (mean 4.68
mm.), with 4Vs-5^ rather loosely coiled whorls. Apex and spire flat,
not protruding, last whorl not or only slightly descending, H/D ratio
0.342-0.413 (mean 0.374). Umbilicus V-shaped, widely open, regularly
decoiling, contained 3.07-4.44 times (mean 3.81) in the diameter.
Apical whorls 1%, sculpture of approximately 18 fine spiral ribs and
finer, more crowded radial swellings. Postnuclear whorls with close-
set, irregularly protractively sinuated radial riblets, often with
periostracal lamellar extensions, growth striae, and vague, much
finer spirals. Sutures very shallow, whorls flat to broad and shallow
supraperipheral sulcus. Periphery with rostrate, prominent keel,
below which is a deep subperipheral sulcus. Lower palatal wall
slightly flattened to strongly rounded umbilical margin. Aperture
elongate-ovate, with very strongly protruding periphery, inclined
about 5° from shell axis. Parietal barriers 3, extending posteriorly
beyond line of vision, finely and regularly beaded after short anterior
portion. Upper slightly higher than 2nd parietal, 3rd usually
markedly reduced in height. Columellar barrier rarely visible in
adults, more frequently in young, a low V-shaped ridge deeply
recessed in aperture, often visible only by extreme tilting of aperture,
not beaded above. Palatal barriers 3-4, lower 3 subperipheral, upper
(when present) supraperipheral. Lower 3 palatals extend posteriorly
one-quarter whorl, finely beaded above for most of length, lower 2
reaching margin, 3rd slightly recessed. Upper palatal varying from
low, beaded ridge less than half height of lower palatals, to a series
of separated tubercles mounted directly on body wall without an
elevated ridge.
The large size, flat spire and non-elevated apex,
wide umbilicus and having the subperipheral sulcus
stronger than the supraperipheral immediately sepa-
rate A. kinlochi from the other Aaadonta. All other
species have quite elevated spires and their umbilici
are much narrower.
Description. — Shell large with 5 rather loosely coiled whorls.
Apex and spire flat, last whorl barely descending below rostrately
keeled periphery of penultimate whorl, H/D ratio 0.369. Keel with
weak supra- and prominent subperipheral sulci. Apical whorls 1%,
sculpture of crowded, very fine spiral riblets, partially eroded, with
weaker radial swellings. Remaining whorls with very irregular,
protractively sinuated radial riblets, occasionally with periostracal
lamellar extensions. Sutures very shallow, whorls flattened above
/— N CM ^-, LO CO ,— *
f— N y^V
0 CD OS . . LO
CO i"N O O
TH/ . CO CD C- CO
CD ^ O t~
O • • •* i-H
'£ as ? as V co <? co i CM 0 oo?
3 oo co °°oo '"T-H co. ua . •* co
« o CM co to •* as ^ c- Q. to -HO
•> ? •> 7 w ? oo f
5 S SS ?: 8 « S «
•t^ rH [J O to' ° C-' -H — ' -H C- & \n
"9 •* ° in 2 CD' ° co'
Q T— i ^ o co oo -^
•H *^s -H >»-• -H «»^- -H s^ /
LO CD o IT- 10
co as m • . in
CD IO CO -^ CO
00 CO
OO C- OO CM rH IO
LO CD CO E- ''t
^ ""f C? 0?
•5R
<2 .—•. •*• <£? CO rH H- LO CD
-t CO x-s + t- + I— I
g ^N ^?? ^,0 to ^,0 ^CO
OO OO OO **"J1 OO *^*
**V. ^ "^s, "^x. "*"*». *->s. ^ '"•*L CD
.B rHrH rH in CO J^ £ ^ rH ^ rH^
,> LO 1C IO ,n LO *"v. \ LO "^ LO
— O. VO rH rH "3
CO^, ^^.H LO^ CO^
LO "^s. LO LO LO LO •"Vv IO "•«*.,.
t-f "^-' T-H CO
UO IO IO
LO IO LO
••••t1 c- co o ir- in*
O O"i O CN 0 CO
co" w" o* io"
O3 00 O CO
C- . CD C- OO C- CD
LO CD C- VO
o
"-1 O O .. O O O O
Oi <? CO *? 0 ? LO ?
(g^i^oo^'i S^ £ °s ° o
•* ^ t- !^ CN °oo °o o oi *— 'co
Q Oy-j ^ CO O CD ° L7- OcD °LO
Jr rH COLO CO(N ^rH
^CO C-J (N ^rH °C-
°io OCD 0^0 o-t*'t*
^ ° 0 ° 0 ° 0 ° 0* ° 0 ° 0
•=> o o o o o ® o
O <7i tr- •**-t< C^ OO
CD CO IO O rH
OD CD CD C— O C-
LO LO CO CD i— 1
CO CD CD C- IT- LO
LO CD CD CD VO
O O O O O O
O O O O O
CO t— I OO LO i— 1 C—
oo oo oo 1— i co UN
-— \ x— v f-^
C- t- rH
rH <N CN
M CO <?" 0 <?'«<?" rH ?' CD ?' rH f
• • •
^COoLOt-CMo •* ,„ 0,0 inrH
C °00 °in °00 Oto rHQj °QQ
o oo o o-a ° LO
_JI ° CM* ° CM* ° CM* ° CM* ° CM* HH ro
o co* *5 SS *5 ^2-
Q co~^c-^ 4" " •*"" mv w
C— """"t1 """"t1 CN CN
OO CO OO OS rH O
CD -^ LO rH CD
CM CM CM CM CO ^t
CO* CO* CO* V CO*
t— O CM (N CM CM
OO ^O LO 00
os CTS o in co c—
•^ CO OO rH
^ t-t _ i-* (N „ CM* _ CM* _, CM
*JC~, ^i rH, CO, C-, rH,
-C rH^M "^CM COcM '"CPos CDos COQq
^OO 0 O5 Oto OOS °O °0 °O
rH <?' OS <?' CM <?' uj ^
•*os 5m C-<M COCM
0 0 °. rH 0 LO 0 oo
z°ri°c!.HHd. ° 2- °S ° 2-
°' si S si °' d. °' ri
in^OS^Co" C- rH •*
CO in in CM rH
OS c- CM CM CO
CM CM CM C- O
I-H rH I-H CM' CM' CM'
CM' CM* CM' CM' CM'
° i
5 1
.Q.ScMinco •* co I-H
0 CM rH ^ -*
2O i-H i-H
5 S
T-H I— 1
5 a-
Z co
as" oo o
c-
Tjr r— O
CM
OO C- CO
rji oo as
s
in in m m
LO
1 rH rH rH
rH
5 2 cl m i
*5
<U O_ OH OH
C CQ CQ n) CO „,
1 g| 1
O W5 i-j
co' § co" o" S o" .0 oo
CJi • X **5P C"* S O3 MCO
CM rH £coa>cias *j o>
Ti< as 3 ^ oo 4; ^
,. in *« ub ifl ^ W3 o^*1
.3 S £? ^rHrHnjrH grH
|a! S 1 3SS ii 2i
111 1 i 1-s.s §& |&
CO* J2 *& CN 3 CN O
(M *-• <N CO -* CD rH
S ]jg g IS S
LO •£) CO LO o ^ "3
i-H o i~l rH *^ rH rH
2 « 2 2g2 g2
£ «£ £ »S 2£
CQ t!CQ CQtiCQ 3CQ
Jc
o o e
s
o o a
*r co
o ^.'
-LJ /• .
oo
t-
OS
oo
0
CO
O
CO*
in
<=
00
CO*
CO
rH
Tf
O
§5?
o 5
Ss
•*
c-
co
o'
CO
O
CM CJS
o in
S'si
in
Ir-
00
in
in oo
CD co
CM CM
00 00
m in
££
CQ CQ
485
abc
a
FIG. 208. a-c, Aaadonta kinlochi, new species. Station 175, Angaur Island, Palau Islands. Holotype. BPBM 158267; d, aperture of
Aaadonta constricta constricta (Semper). Paratype. FMNH 46245; e, aperture of Thaumatodon hyatricelloides (Mousson). Paratype.
Zurich. Scale line equals 1 mm., d-e, greatly enlarged. (SG).
486
SYSTEMATIC REVIEW
487
with shallow supraperipheral sulcus and acutely protruded rostrate
keel, only slightly compressed laterally. Color yellow-white, with a
few irregular, reddish markings above, prominent near periphery,
fading out to suture and on lower palatal wall, quite prominent in
umbilicus. Apex reddish in tone, without discrete markings. Um-
bilicus broadly open, V-shaped, regularly decoiling, contained 3.84
times in the diameter. Aperture subquadrangular with rostrate
periphery, upper palatal margin parallel to plane of coiling, lower
palatal wall slightly flattened, inclined about 5° from shell axis.
Parietal barriers 3, extending posteriorly beyond line of vision,
regularly and finely beaded after anterior fourth; upper very high,
2nd slightly, and 3rd markedly reduced in height and also in size of
beading. Columellar barrier not visible except by extreme tilting of
aperture, a very deeply recessed, weak ridge without beading. Palatal
barriers 3, all subperipheral, about equal in height, lower 2 reaching
apertural margin, 3rd slightly recessed, all prominently and finely
beaded above. Above periphery, a row of small tubercles represents
remnants of a 4th palatal barrier (not visible in standard drawings of
shell). Height of holotype 1.68 mm., diameter 4.54 mm.
Holotype. — Palau Islands: Angaur, Station 175,
area north of shrine, near edge of guano pit at 75-100
ft. elevation. Collected by Kiyoko and Yoshio Kondo
on April 18, 1936. BPBM 158267.
Range. — Angaur, Palau Islands.
Paratypes. - BPBM 158265-8, BPBM 158312-3.
Material. — All from type locality (173 specimens,
same as list of paratypes).
Remarks. — The flattened or at most barely
protruding spire is an immediate criterion for iden-
tification. Most examples had the spire flat, but rarely
it was a trifle elevated. More variation was seen in the
apertural barriers. The great majority of larger
individuals had the columellar barrier a deeply
recessed trace, often visible only by severe tilting of
the aperture. In many younger individuals, however,
the barrier reached nearly to the lip edge and was
visible from all angles. Other young shells had the
barrier recessed as deeply as in the type. The presence
or absence of the supraperipheral palatal trace barrier
showed no age-correlated pattern of variation. Even
when present it was rather weak and time did not
permit cleaning of enough apertures to work out its
pattern of occurrence. About 45 apertures were
checked with all stages of development being observed.
Only 29 of the 173 specimens were adult, and only
12 examples were collected alive.
Great pleasure is taken in dedicating this beautiful
species to the late George G. Kinloch, whose early
interest in his nephew's shell collection diverted me on
the road to malacology instead of entomology.
Description of soft parts. — Foot and tail as in A. constricta,
extended length less than diameter of shell. Sole and pedal grooves
typical, no caudal horn or middorsal groove. Slime network weakly
reticulated. Head protruded beyond edge of foot, ommatophores
long, eyespot small, circular. Gonopore in normal position.
Body color yellow-white, no darker markings.
Mantle collar (MC) swollen in drowning, edges at parietal-
palatal margin masking pneumostome, glandular extensions onto
pallial roof extensive on lower part of palatal and parietal walls.
Anus (A) without clear external groove through mantle collar.
Pallial region (fig. 200a) extending nearly two-thirds of a whorl
apically, length about 5.8 mm. Lung roof clear, without granulations.
Kidney (K) about 1.7 mm. long, base lying above intestinal loop,
head of spermatheca indenting lower side, part of kidney abutting on
hindgut. Ureter (KD) a wide tube opening (KX) where kidney
reaches hindgut margin. Heart (H) slightly more than half length of
kidney, nearly paralleling hindgut. Principal pulmonary vein (HV)
simple, unbranched, paralleling hindgut, fading out short of mantle
collar. Hindgut (HG) typical.
Ovotestis (G) (fig. 200b) typical of subfamily, individual alveoli
appearing iridescent. Hermaphroditic duct (G) long, more convoluted
than in A. constricta, narrowing abruptly and running straight
before entering carrefour (X). Latter smaller and more elongated.
Albumen gland (GG) of loosely connected alveoli, opening into head
of uterus. Talon (GT) very elongated, slender, lying imbedded in
surface of albumen gland. Prostate (DG) short, a slender tube into
which three rows of large acinar alveoli empty, lying next to uterus
but not attached in any way. Uterus (UT) a thin-walled tube,
slender above, broadly expanded for basal three-eighths, sharply
constricted just before entering free oviduct (UV).
Vas deferens (VD) slender, passing down to penioviducal angle,
then up alongside penis to enter head of epiphallus. Vas not bound
to other organs, but lying free. Epiphallus (E) sharply delineated
from vas deferens, one-half length of penis, internally with two
longitudinal pilasters that continue into penis. Penial retractor (PR)
arising from diaphragm just below apex of pallial cavity, inserting
onto apex of epiphallic-penial loop and fusing with tissue. Penis (P)
about 1.7 mm. long, tapering from upper section to distal end.
Epiphallic pilasters continuing into penis, one splitting to form a
weak pocket, the larger arm continuing into atrium (not shown in
fig. 200c), shorter arm ending. Second pilaster extending to atrium.
Atrium (Y) long, with 2-3 pilasters.
Free oviduct (UV) and spermatheca (S) as in A. constricta.
Vagina (V) absent.
Free muscle system as in A. constricta. Digestive system
differing from A. constricta only in having stomach extend over a
slightly longer area.
Jaw fragmented on mounting, separate plates four or five times
as long as wide, not fused.
Radula with 6 laterals, marginal sections folded under in mount.
Central tooth about 6-7|u wide, Ip long.
(Based on BPBM 158265, BPBM 158266, five examples, whole
specimen diameter 4.90 mm. with 5'4 whorls.)
ZOOGEOGRAPHY
Throughout much of the Pacific Islands region,
the Endodontidae and the Charopidae have over-
lapping distributions. Both families were common or at
least represented in Palau, the Lau Archipelago of Fiji,
Ellice Islands, Tonga, Western Samoa, American
Samoa, Cook Islands, and the Society Islands quite
early in this century. The Endodontidae extended
further into Polynesia and speciated widely in the
Tuamotu, Austral, Marquesas, Gambier, and Hawaiian
Islands. Both families are known as fossils from the
Marshall Islands. The Charopidae are common in the
Mariana, Caroline, Palau, Fiji, Tonga, Ellice, Western
Samoa, American Samoa, Cook and Society Islands,
plus many extra-limital Pacific areas, including Juan
Fernandez, Kermadec, Lord Howe, Norfolk, New
Caledonia, New Hebrides, and the Austrozelandic
region. Detailed zoogeographic analysis is deferred
until Part II of this monograph, since questions of
species diversity, island area and species abundance,
possible replacement phenomena, and relative abun-
dance species require discussing both families.
Thus the present discussion is limited to a review
of the general distributional patterns found in the
Endodontidae, and a few comments on the Rapa
Island radiation. Earlier (pp. 107-108) evidence was
presented for the Endodontidae being a more general-
ized group than the Charopidae. It was suggested that
the Charopidae could be derived from the endodontid
structural patterns, but not the reverse. The fact that
some genera of extant Charopidae show relict
Gondwanaland distributions (Solem, unpublished),
whereas the Endodontidae are strictly Pacific Island
inhabitants, leads to difficulties in zoogeographic
interpretation according to today's conventional
wisdom.
It is virtually universally accepted now that the
Polynesian Islands have been populated by overseas
dispersal in quite recent times. The brilliant synthesis
of Zimmerman (1948) has been amply bolstered by
subsequent studies. Yet the highly endemic and
antique nature of the Pacific Island land snail fauna,
first pointed out by Pilsbry (1900b), and subsequently
commented on by Pilsbry (1916, 1921), Cooke (1926),
Germain (1932, 1934), and Solem (1959a, 1969c) cannot
be dismissed. The recent demonstration (Solem and
Yochelson, in press) that one of the earliest known
fossil land snails, the Pennsylvanian Anthracopupa,
cannot be separated on more than generic level from
the present day Tornatellinidae, also basically restrict-
ed to the Pacific Islands, serves to reinforce the
phyletic age of these taxa. There is ample evidence of
sea-floor subsidence in Micronesia, and the former
high-island status of Bikini, Eniwetok (Leopold, 1969),
and Midway (Ladd et al., 1967, 1970) atolls has been
well established by work of the past decade. The
exciting data from plate tectonics are creating a
revolution in the zoogeographic interpretations of
continental areas, but to date has shed little light on
the problems of Pacific Island organisms.
Prior to the Tertiary, there undoubtedly were
many more islands in the Pacific Basin than there are
today. Gaps between islands would have been less,
hence the chances for successful overseas dispersal
greatly increased over those that now exist. While
probably few, if any, of the present islands date from
earlier than the Eocene, the existence of many
scattered islands in the Pacific Basin must be
accepted. Hence I stand by my earlier conclusion
(Solem, 1959a, p. 326) that "...the present land snail
fauna of the Pacific Islands originated in at least the
early Mesozoic and has been able to survive by being
passively dispersed at very infrequent intervals from
island to island."
The proposed great age of the Pacific Island land
snail fauna thus stands in great contrast to the very
recent vintage proposed for the other components of
the fauna and flora, yet it is consistent with available
fossil and biogeographic evidence.
The fossil land snails from Bikini and Eniwetok
(pp. 116-118) all can be assigned to modern species
groups, although ranging in age to mid-Miocene. In a
biogeographic sense, they demonstrate the presence of
both Endodontidae and Charopidae in the Marshall
Islands during the Miocene to Pliocene. Both groups
subsequently became extinct as the high islands sunk
and became atolls. These fossils demonstrate that
little shift occurred in basic distributions, other than
range restrictions because of extinctions, since the
Miocene. The fossils yield no data concerning actual
rates of evolution, since they are referable to extant
species groups. The two endodontid fossils, Cooke-
concha subpacificus (fig. 92) and Minidonta in-
expectans (fig. 62d), both belong to the most general-
ized extant groups (figs. 57, 58), while the two
charopids belong to highly specialized genera. Cooke-
concha is limited to the Hawaiian Islands, while
Minidonta has a fringing distribution around the
488
ZOOGEOGRAPHY
489
Cook-Society-Tuamotu-Austral-Marquesas center of
diversification (pp. 128-129). The most generalized spe-
cies of Minidonta are found on scattered islands
(Henderson, Mangareva, Raivavae, the Manua group
of American Samoa) and fossil on Bikini Atoll.
Specialized species lived until recently on Mangareva
(simulata group), Raivavae and Rurutu (anatonuana
group), Raivavae (micraconica group), and Aitutaki
(rotellina). The 2,700 mile range, Henderson to Samoa,
does not include the Pliocene or Pleistocene Bikini
species, which effectively doubles the known dis-
tributional range.
Primary derivatives from Minidonta (figs. 57, 58)
include Mautodontha (Cook, Society, Tuamotu), An-
ceyodonta (Mangareva), and Australdonta (Austral
Islands exclusive of Rapa). Mautodontha probably
represents the stem group for Taipidon (Marquesas)
and Opanara (Rapa) of the genera extra-limital to its
basic distribution, plus local derivatives such as
Kleokyphus and Pseudolibera in the Tuamotus, and
Nesodiscus and Liber a in different parts of the Society
and Cook Islands. Gambiodonta and Rikitea are local
Mangarevan developments, while the Marquesan
Planudonta evolved locally from Taipidon. On Rapa,
there was an extensive radiation (see below). In
Hawaii, Cookeconcha represents the group from which
both Endodonta and Nesophila are descended.
The vast majority of the endodontid genera thus
show a quite coherent and simple distributional
pattern clustered around the two generalized taxa,
Minidonta and Cookeconcha. The latter led to the
Hawaiian radiation; the former produced the Poly-
nesian diversity, with the Rapan and Marquesan
genera representing the greatest degree of anatomical
change from the generalized Minidonta. Since Cooke-
concha is known as a Miocene fossil and Minidonta
as a Pliocene or Pleistocene taxon, the conventional
interpretation would be to view these as relatively
recent radiations, probably occurring no earlier than
the Miocene and much more probably in the Pliocene
or Pleistocene. Arguing against this are three major
facts: 1) the peculiar distribution shown by the most
advanced endodontids; 2) the total absence of
endodontids from other areas of the world; and 3) the
very generalized, "protosigmurethran" anatomy of the
Endodontidae.
Thaumatodon, Aaadonta, Zyzzyxdonta, and
Priceconcha are an anatomically uniform group of
genera that are sharply distinguished from the remain-
ing endodontids (pp. 110-112). Aaadonta, which is
specialized in shell sculpture, is restricted to the Palau
Group; Zyzzyxdonta and Priceconcha are specialized
taxa from Lau Archipelago; while Thaumatodon
ranges from Lau and Ellice Islands to Rarotonga, with
a relatively simple intrageneric distributional pattern
(pp. 446-448; fig. 190). The most generalized species are
T. decemplicata (Mousson) from Vaitupu and Nuku-
fetau in the Ellice Islands, plus T. multilamellata
(Garrett) from Rarotonga, Cook Islands. T. hys-
tricelloides (Mousson) from Upolu, Western Samoa,
and two Tongan species, T. euaensis from Eua and T.
vavauensis from Vavau, show a coherent pattern of
greater specialization. Four species from the Lau
Archipelago, T. corrugata, T. subdaedalea (Mousson),
T. laddi, and T. spirrhymatum, show yet a third level
of specialization. These occurrences are most easily
interpreted as representing a radiating pattern out-
ward from a focus on the Lau Archipelago, with the
Ellice and Cook species representing one wave, the
very similar Tongan and Samoan snails a second, and
the most specialized Lau taxa forming a third group
from which the local genera, Priceconcha and Zyzzyx-
donta, were derived. The Palau Island Aaadonta
shows a different pattern of conchological special-
ization (loss of major radial sculpture, keel devel-
opment) than any of the species groups in Thaumato-
don, but is unquestionably very closely related, despite
its retention of low penial pilasters.
Thus this complex of genera has a distributional
pattern suggesting dispersal from the "New Guinea
core" with subsequent extinction in the core region.
Despite their obvious specializations, they are
endodontids, although with a distinct structural gap
from the other genera. In comparison with the
Charopidae, the "Thaumatodon complex" species have
penetrated a shorter distance into both Micronesia
(charopids are common on the Caroline and Mariana
Islands) and Polynesia (charopids reach the Society
Islands). Whereas the bulk of endodontid genera
suggest in situ radiation, the Thaumatodon- Aaadonta
complex suggests colonization after diversification.
As emphasized repeatedly, no endodontids are
reported from other parts of the world, and the
anatomy of the Endodontidae is the most generalized
of the sigmurethran lineage. The Charopidae are
dominant in Australia, New Zealand, New Caledonia,
South Africa (Solem, 1970c), southern South America,
and a few islands such as Lord Howe and St. Helena,
but are only weakly represented in New Guinea
(Solem, 1959b, 1970a) and Indonesia (Solem, 1964).
They seem to have been replaced by the more
advanced limacoids and helicoids in most continental
areas. As mentioned above, some charopid genera show
relict Gondwanaland distributions, yet the Charopidae
have colonized more of the Pacific Islands than the
advanced endodontids of the Thaumatodon- Aaadonta
lineage.
The endodontids thus present a distributional
anomaly, in that their most generalized complex shows
a simple and coherent Polynesian radiation pattern,
yet their most advanced group shows a less successful
Pacific Island colonization pattern than does the
Charopidae, a family with Gondwanaland relict dis-
tributions that itself has been effectively replaced on
continental areas. The Charopidae could be derived
from the Endodontidae, but not the reverse. Ex-
490
SOLEM: ENDODONTOID LAND SNAILS
planation of this pattern must be speculative, at least
until the relationships within the Charopidae are
sorted out, but one hypothesis can be offered as a
thought-provoking suggestion. Based on recent work
on plate tectonics in the Australian region, summa-
rized by Raven and Axelrod (1972), I suggest that the
Charopidae came north with the Australian plate,
gaining entrance to the Polynesian region when the
Pacific and Australian plates collided and underwent
fragmentation about the Eocene. New Guinea is a
highly complex mass of tectonic fragments. It is
conceivable that the advanced endodontids were
present on the pre-Australian plate-New Guinea
collision area, were able to start their colonization
movement as an early byproduct of the initial
collision, only to be subsequently replaced by Asian
taxa and bypassed by the more vagile charopids. This
assumes that 1) the generalized endodontids have been
stable on the Pacific Islands since the Mesozoic; 2)
advanced endodontids (Aaadonta-Thaumatodon) date
from early Eocene to pre-Eocene; 3) charopids are a
late Eocene to post-Eocene wave of immigrants into
the Pacific; and 4) endodontids and most charopids
have been replaced in the Indonesia-New Guinea axis
by advanced continental land snails of Asian origin
probably in Oligocene or more recent times.
The above summarizes the basic outline of
distribution, with more detailed discussions postponed
until data from the Charopidae can be incorporated to
provide discussions of abundance and local diversity. It
is appropriate, however, to review here the distribution
patterns of the quite extraordinary Rapa Island
radiation. This comprises one-eighth of the total
species, one-fifth of the genera, and 22 per cent of the
total specimens reviewed in Part I. Because anatomi-
cal and detailed locality data were available, far more
can be said about the patterns on Rapa than for other
islands of the Pacific.
Sometime between May 13 and May 17, 1828,
Hugh Cuming, or one of his assistants (see St. John,
1940 for Cuming's itinerary), collected Ruatara opa-
rica oparica on Mt. Tanga, Rapa. It is surprising, in
view of the many tornatellinids and other species
dating from this trip, that only one Rapan endodontid
was taken by his party. Almost 100 years later, in
July, 1921, Mrs. A. M. Stokes collected 10 specimens of
Ruatara oparica normalis near Morongoto.
All of the remaining 4,078 endodontids studied
during this project were assembled by members of the
Mangarevan Expedition from the Bernice P. Bishop
Museum during the month of July, 1934. Brief
discussions of the mollusks collected on Rapa have
been published by Cooke in Gregory (1936, pp. 45-47)
and Kondo and Clench (1952, pp. 81-21). From
published data and the field notebooks in the Bishop
Museum, it is obvious that more intensive collecting
was done on Rapa in July, 1934 than ever has been
done on any other Polynesian Island.
Rapa Island is the remnant of a large volcanic
crater, open at one side to the sea, with a rim of steep
mountains, ranging from 600-2,000 ft. elevation. There
is some valley formation (Chubb, 1927, pp. 293, 295),
but much of the terrain is nearly vertical (Cooke and
Kondo, 1960, p. 23, top). While Fosberg and St. John
reached the top of its highest mountain, Mt. Perahu,
most collecting was done at lower elevation. Quoting
Cooke in Gregory (1936, p. 45) "A very large part of
the island has been burned over by the natives."
Earlier on the same page, he indicated that "The
peaks, where not too precipitous, and the heads of the
valleys and gullies are well covered with endemic
forests." Even in 1934, much of the native forest had
been denuded, and Clarke (1971, p. 9) reported that
forest cover had shrunk subsequently. As outlined
above (p. 101), it is quite possible that the endodontid
radiation is now extinct.
The 4,105 specimens of Rapan endodontids belong
to five genera and 17 species. Thirteen of the species
are monotypic, one has two races; and three species
have three geographically isolated morphs. Soft
anatomy was illustrated for 22 of the 24 taxa and
parts noted for the other two. These species form a
monophyletic unit, separated from extra-limital taxa
primarily by modifications in the penial region. From
any single extralimital genus the Rapan taxa show
different average patterns of conchological criteria, but
the basic difference is anatomical. The typical penial
pilaster pattern in the Endodontidae is for two equal-
sized pilasters that unite apically and normally are at
most slightly higher than wide. In the Rapan taxa,
unless secondarily modified, the pilasters are much
higher than wide and form lamellar stimulatory
organs. Rhysoconcha is secondarily modified to the
low pattern, and in Ruatara there is fusion of the two
pilasters into one, probably as an elaboration of the
pilaster change seen in Opanara perahuensis (fig. 97i).
Generally the Rapan species have a fleshy extension to
the penis head, a character shared with Australdonta
and the Marquesan genera, but this apparently has
been secondarily reduced in several Rapan species.
Changes in talon length, shape of the hermaphroditic
duct, and relative lengths of the prostate-uterus are
minor.
Opanara is the most generalized genus found on
Rapa, and represents an approximation of the base
stock from which Rhysoconcha, Ruatara, Orangia,
and Kondoconcha were derived. Rhysoconcha is the
result of secondary size reduction (pp. 255-256), and
the changes shown by the Rhysoconcha species are
sufficiently large that it is impossible to equate
current species groups of Opanara with the possible
ancestral form leading to Rhysoconcha. To the limited
extent that it has an exceptionally high mean whorl
count and lacks a fleshy extension to the penis head,
O. depasoapicata, one of the smaller Opanara,
suggests how the reduction trend might have started.
ZOOGEOGRAPHY
491
It is not considered to be an intermediate or ancestral
form.
Ruatara is characterized by umbilical closure
through contraction, coiling of the hermaphroditic
duct, presence of only a single pilaster in the penis
which lacks a fleshy extension to the head, has a
distinct vaginal region and an elevated spire. Opanara
perahuensis has the umbilical form and elevated spire
of Ruatara, while the penial pilaster pattern is
intermediate between the condition found in typical
Opanara and the modified Ruatara pattern. The
apical genitalia of O. perahuensis are unknown, but
the remaining features of the terminal genitalia, shell
sculpture, and apertural barriers are of the Opanara
pattern. While O. perahuensis indicates how the
distinctive features of Ruatara can be derived from the
Opanara structures, it is not an intermediate species.
There are, however, more similarities between Ruatara
and Opanara than between any other pair of Rapan
genera.
Orangia shows more conchological than anatom-
ical changes, the latter consisting mainly of talon
elongation and unequal size of the penial pilasters.
The species of Orangia show rather gross differences in
penial size and pilaster formation (fig. 121), but
otherwise it is anatomically conservative.
Conchological differences of greatest importance are
the reduction to 2 parietals, closure of the umbilicus
by lip reflexion (fig. 118), tendency toward devel-
opment of a keeled periphery, weak supraperipheral
sulcus, and development of secondary spiral sculpture.
The form of umbilical closure is quite different from
that seen in Ruatara, which is simple umbilical
contraction. Opanara, Ruatara, and Rhysoconcha all
show no tendency toward formation of a keel,
secondary sculpture, or a supraperipheral sulcus.
Kondoconcha is similar to Orangia in having only 2
parietals, developing a tendency toward peripheral
angulation, and in its large size. The open umbilicus,
striking reduction of sculpture, unique development of
lateral accessory lamellae on the parietals, very high
whorl count (mean 6%-) and many accessory palatal
traces offer a marked contrast to Orangia. Separate
derivations of Orangia and Kondoconcha from the
Opanara base stock are certain. Their similarities are
correlatives of large size, while their differences are not
size dependent.
Geographical patterns of distribution on Rapa are
consistent with the idea of Opanara being generalized
and close to the basic structural pattern of the
colonizing stock, while the other genera are more
specialized and structurally modified. Distribution
patterns of Opanara are shown in Figures 99, 100, and
101. The closely related O. altiapica and O. caliculata
plus O. megomphala show a relict pattern of geograph-
ically isolated populations restricted to small areas. O.
areaensis has a moderately wide distribution in
lowland areas, with two pockets of subspeciation, one
(densa) contiguous to the main area, the other
(microtorma) isolated by geographical distance (fig.
101). All the remaining species are restricted, so far as
is known, to the upper reaches of Mt. Perahu (fig. 99).
The gross differences in penial size and alteration in
penial pilasters seen in the Mt. Perahu species (figs.
96b, d, f, h; 97b, i) are far greater than the differences
seen between the geographically isolated taxa. Since
the Mt. Perahu species live at the same stations,
emphasis of isolating mechanisms is required to lessen
the possibility of accidental interspecific matings and
thus preserve specific isolation.
Of the derivative genera, Orangia has the greatest
morphologic gap from Opanara and shows the
greatest degree of internal differentiation. The most
specialized species, Orangia sporadica and O. maitua-
tensis, are widely distributed or geographically iso-
lated, respectively, in lowland areas, while the least
specialized form, O. cookei, is fragmented into isolated
subspecies and reaches higher elevations (fig. 117).
Kondoconcha is known only from the restricted area
between Morongoto and Mt. Tevaitahu at about 750
ft. elevation and thus is not referable to any particular
geographic pattern. Rhysoconcha (fig. 109) is widely
distributed at lower and middle elevations, but
apparently does not reach the upper elevations.
Ruatara is, at the same time, the most widely
distributed and least clearly internally differentiated
genus. It is quite common at low and middle
elevations, but also reaches 1,850 ft. on Mt. Perahu
and 1,000 ft. on Mt. Mangaoa. A subspecies with
greatly reduced palatal barriers has developed in one
lowland area (reductidenta), while a form with normal
barriers, crowded ribbing, and reduced size lives at
intermediate elevations on Mt. Tanga (oparica).
Besides the nomenclaturally recognized subspecies,
there is a dichotomy in regard to number of parietal
barriers between the northern and southern parts of
Rapa (pp. 268-269).
There is a clear pattern on Rapa of generalized
species being confined to or mainly present at higher
elevation, while derivative taxa are prevalent at lower
elevations, showing subspeciation tendencies when
penetrating to upper elevations. This pattern does
suggest that species replacement has occurred and
that competitive exclusion may exist. Analysis of
station records and discussion of relative abundance
will be given in Part II.
The most striking morphological change on Rapa
concerns the frequency of umbilical closure. Of the 185
endodontid taxa, seven of the eight with closed
umbilici, (the other is the Cook Island Mautodontha
punctiperforata), and all three taxa with barely
perforate umbilici are found on Rapa. This closure has
been effected at least two different times, since the
pattern in Ruatara is closure by simple contraction,
while in Orangia the closure is effected by reflection of
the columellar lip over a narrowed umbilicus (fig. 118).
On Mangareva, there is frequent narrowing of the
492
SOLEM: ENDODONTOID LAND SNAILS
umbilicus until the last whorl decoils rapidly (figs.
83b; 87f) or the umbilicus remains very narrow (figs.
81b; 90b, c, f). In all' other areas, with rare exceptions,
the umbilicus is widely open or modified to form a
brood chamber.
Rapa is by far the most southern of the
Polynesian Islands from which endodontids are known
and is washed by a cold current. Almost certainly the
warm equatorial countercurrent never extends this far
south. The climate is temperate, with mean tempera-
tures of 76°F in summer and 58°F in winter. Although
rainfall statistics are limited (Clarke, 1971, p. 11), the
position of the island is such that a relatively evenly
spaced and extensive rainfall pattern is indicated. The
growing of coffee at low elevations (500 ft.) similarly
implies wet conditions. Under these circumstances, the
need for an umbilical brood chamber is lessened and
the inconvenience of arthropod egg laying in the
umbilicus could combine to provide selective pressure
for umbilical closure.
The second major change on Rapa concerns a
pattern of variation within species. In several species,
Opanara areaensis, Opanara megomphala, Ruatara
oparica, and Orangia cookei, there have been sub-
species developed characterized by reduced diameter,
reduced whorl count, increased number of major radial
ribs, and greatly increased crowding of the radial ribs.
Two pairs of species, Opanara altiapica and O.
caliculata, then Rhysoconcha variumbilicata and R.
atanuiensis, have similar variations, but in a different
pattern. In these pairs, the largest morph has the
increased rib count, much more crowded ribbing, and
possibly a lower whorl count, although the evidence
for the latter is fragmentary as yet.
SUMMARY
The 154 non-Hawaiian species of Endodontidae
are reviewed in detail and the 31 Hawaiian taxa are
surveyed to a lesser extent. A total of 102 species level
taxa and 19 genera are described as new (see "List of
Taxa," pp. 122-124).
Patterns of conchological and anatomical vari-
ation within the family are reviewed and correlated
patterns of variation outlined. Shell sculpture, for
example, is shown to become greatly reduced in
prominence once a shell size of 4.75 mm. is attained,
but variation in the characteristic apertural barriers is
more phyletically correlated than size influenced.
Progressive anatomical trends within the Endodon-
tidae include two experiments in forming an epiphallic
zone, one by adding glandular tissue between the penis
apex and penial retractor muscle, the other by
forming an epiphallic section to the penis. Marquesan
genera show a unique additive pustulose zone in the
penis.
Sympatric congeners are demonstrated to differ in
terminal genital structures, suggesting character dis-
placement has occurred to aid species isolation.
The species are shown to follow a repetitive
pattern of specializations in different areas, termed the
Minidonta, Mautodontha, Nesodiscus, and brood-
chamber levels (figs. 57, 58). Each level shows
distinctive conchological features, but arrived at in
different ways in each geographic area.
Major emphasis is given to determining direction
of character change and to place the endodontids
within a broader context of land-snail phylogeny. New
interpretations of land-snail phylogeny are outlined,
and a revised family classification of the endodontoids
proposed.
The monograph ends with a brief review of overall
zoogeography of the endodontids and a review of local
distribution and variation patterns on Rapa Island.
493
REFERENCES
ADAMS, HENRY and ARTHUR ADAMS
1854-1858. The genera of recent Mollusca; arranged according to
their organization. Volume 2. London, J. Van Voorst. 661 pp.
A DAMSON, A. M.
1935. Non-marine invertebrate fauna of the Marquesas (exclusive
of insects). Occ. Pap. Bernice P. Bishop Mus., 11, (10), pp. 1-39.
1936. Marquesan Insects: Environment. Bull. Bernice P. Bishop
Mus., 139, pp. 1-73, 9 figs., 8 pis.
ALBERS, JOH. CHRIST.
1850. Die Heliceen, nach naturlicher Verwandtschaft. Berlin, Th.
Chr. Fr. Enslin. 262 pp.
1860. Die Heliceen, nach natiirlicher Verwandtschaft. Zweite
Ausgabe. Leipzig, Wilhelm Engelmann. 359 pp. (ed. by Eduard
von Martens)
ANCEY, C. F.
1889a. Mollusque terrestre nouveau d'Oceanie. Naturaliste, (2), 11
(49), pp. 71-72 and (50), p. 84.
1889b. Diagnoses de Mollusques nouveaux. Naturaliste, (2), 11
(53), p. 118.
1889c. Description de Mollusques nouveaux d'Oceanie. Naturaliste,
(2), 11 (59), pp. 190-191.
1889d. Etude sur la Faune malacologique des lies Sandwich. Bull.
Soc. Malacol. France, 6, pp. 171-258.
1899. Some notes on the non-marine molluscan fauna of the
Hawaiian Islands, with diagnoses of new species. Proc. Malacol.
Soc. London, 3, pp. 268-274, pi. 12.
1904. Report on semi-fossil land shells found in the Hamakua
District, Hawaii. Jour. Malacol., 11, (3), pp. 65-71, pi. 5.
ANTON, HERMANN EDUARD
1839. Verzeichniss der Conchylien Welche sich in der Sammlung
von Hermann Eduard Anton. Halle. 110 pp.
AUBERT DE LA RUE, E. and R. SOYER
1958. Faunule de mollusques terrestres recueillie dans 1'ile de
Makatea (Archipel des Tuamotu). Bull. Mus. Nat. Hist. Nat.,
Paris, n.s., 30, (4), pp. 365-366.
BAKER, F. C.
1945. The molluscan family Planorbidae. Urbana, Univ. Illinois
Press. 530 pp., 141 pis.
BAKER, HORACE BURRINGTON
1927. Minute Mexican land snails. Proc. Acad. Nat. Sci. Phila., 79,
pp. 223-246, pis. 15-20.
1938a. The endodont genus Otoconcha. Proc. Malacol. Soc.
London, 23 (2), pp. 89-91, 2 figs.
1938b. Zonitid snails from Pacific Islands. Part 1. Southern genera
of Microcystinae. Bull. Bernice P. Bishop Mus., 158, pp. 1-102,
20 pis.
1940. Zonitid snails from Pacific Islands. Part 2. Hawaiian genera
of Microcystinae. Bull. Bernice P. Bishop Mus., 165, pp. 103-202,
pis. 21-42.
1941. Zonitid snails from Pacific Islands. Parts 3 and 4. Genera
other than Microcystinae and Distribution and indexes. Bull.
Bernice P. Bishop Mus., 166, pp. 203-370, pis. 43-65.
1955. Heterurethrous and aulacopod. Nautilus, 68 (4), pp. 109-112.
1956. Family names in Pulmonata. Nautilus, 69 (4), pp. 128-139.
1962a. Puerto Rican Holopodopes. Nautilus, 75 (3), pp. 116-121.
1962b. Puerto Rican land operculates. Nautilus, 76 (1), pp. 16-22.
1963. Type land snails in the Academy of Natural Sciences of
Philadelphia. Part II. Land Pulmonata, exclusive of North
America North of Mexico. Proc. Acad. Nat. Sci., Phila., 115, pp.
191-259.
BALDWIN, D. D.
1893. Catalogue, land and fresh water shells of the Hawaiian
Islands. Honolulu, Press Publishing Company. 25 pp.
BAYNE, C. J.
1973. Physiology of the pulmonate reproductive tract: location of
spermatozoa in isolated, self-fertilizing succinid (sic) snails (with
a discussion of pulmonate tract terminology). Veliger, 16 (2), pp.
169-175, 2 figs.
BECK, H.
1837. Index Molluscorum praesentis aevi musei principis
augustissimi Christian! Frederici. Hafniae. 124 pp.
BEDDOME, R. H.
1889. Descriptions of land-shells from the Island of Koror, Pelew
Group. Proc. Zool. Soc. London, 1889, pp. 112-116, pis. XI-XII.
BERRY, A. J.
1962. The growth of Opisthostoma (Plectostoma) retrovertens
Tomlin, a minute cyclophorid from a Malayan limestone hill.
Proc. Malacol. Soc. London, 35 (1), pp. 46-49.
BINNEY, W. G.
1875. On the lingual dentition and genitalia of Partula and other
Pulmonata. Proc. Acad. Nat. Sci., Phila., 27, pp. 244-254, pis. 19-
21.
1885. Notes on the Jaw and Lingual Dentition of Pulmonate
Mollusks. Ann. N. Y. Acad. Sci., 3, pp. 79-158, pis. 2-17.
BLANFORD, W. T. and H. H. GODWIN-AUSTEN
1908. The fauna of British India, including Ceylon and Burma.
London, Taylor & Francis. 311 pp.
BLINN, W. C.
1964. Water in the mantle cavity of land snails. Physiol. Zool., 37
(3), pp. 329-337.
BOUILLON, J. and W. DELHAYE
1970. Histophysiologie comparee des cellules renales de quelques
Gasteropodes Pulmones terrestres et dulcaquicoles. Ann. Sci.
nat, Serie Zool., (12), 12, pp. 1-26.
BUCK, P. H.
1939. Report of the Director for 1938. Bull. Bernice P. Bishop
Mus., 164, pp. 1-32.
494
REFERENCES
495
CAUM, EDWARD L.
1928. Check list of Hawaiian land and fresh water Mollusca. Bull.
Bernice P. Bishop Mus., 56, pp. 1-79.
CHUBB, LAWRENCE JOHN
1927. The geology of the Austral or Tubuai Islands (Southern
Pacific). Quart. Jour. Geol. Soc. London, 83 (2), pp. 291-316, pi.
23, 7 text figs.
CLAPP, WILLIAM F.
1923. Some Mollusca from the Solomon Islands. Bull. Mus. Comp.
Zool., Harv. Coll., 65 (11), pp. 349-418, 5 pis., 55 text figs.
CLARKE, J. F. GATES
1971. The Lepidoptera of Rapa Island. Smithson. Contr. Zool., 56,
pp. 1-282, 29 pis., 175 text figs.
CLESSIN, S.
1881. Nomenclator Heliceorum viventium. Cassellis, Theodori
Fischeri. 617 pp.
CLIMO, F. M.
1969a. Classification of New Zealand Arionacea (Mollusca:
Pulmonata) I. The Higher Classification. Rec. Dominion Mus.
Wellington, 6 (12), pp. 145-158, 5 figs.
1969b. Classification of New Zealand Arionacea (Mollusca:
Pulmonata) II. A revision of Champa Subgenus Ptychodon
Ancey, 1888. Rec. Dominion Mus. Wellington, 6 (14), pp. 175-
258, 34 figs., pis. 1-11.
1970. Classification of New Zealand Arionacea (Mollusca:
Pulmonata) III. A Revision of the genera Charopa Albers, 1860
(excluding subgenus Ptychodon Ancey, 1888), Phenacharopa
Pilsbry, 1893, and Flammocharopa n. gen. (Endodontidae:
Endodontinae). Rec. Dominion Mus. Wellington, 6 (18), pp. 285-
366, 22 figs., pis. 1-9.
1971a. Classification of New Zealand Arionacea (Mollusca:
Pulmonata) IV. A Revision of the subfamily Otoconchinae
Cockerell (Punctidae Morse). Rec. Dominion Mus. Wellington, 7
(6), pp. 43-49, 2 figs.
1971b. Classification of New Zealand Arionacea (Mollusca:
Pulmonata) V. Descriptions of Some New Phenacohelicid
Taxa (Punctidae: Phenacohelicinae). Rec. Dominion Mus.
Wellington, 7 (11), pp. 95-105, 4 figs, pi. 1.
COCKERELL, T. D. A.
1893. A check-list of the slugs. Conchologist, 2 (8), pp. 185-228.
1925. A visit to the Hawaiian Islands. Nautilus, 39 (3), pp. 76-83.
1933. A new Endodonta from the Hawaiian Islands. Nautilus, 47
(2), p. 58.
CONNOLLY, MARCUS
1939. A monographic survey of South African non-marine
Mollusca. Ann. S. Afr. Mus., 33 (1), 660 pp., 19 pis.
COOKE, C. MONTAGUE
1926. Notes on Pacific land snails. Proc. 3rd Pan-Pac. Sci. Congr.,
pp. 2276-2284.
1928. Three Endodonta from Oahu. Bull. Bernice P. Bishop Mus.,
47, pp. 13-27, 7 figs.
1929. Notes on Marquesan landshells. In Proc. Hawaiian Acad.
Sci., Bernice P. Bishop Mus., Spec. Pub., 14, p. 15.
1934. Land shells of Makatea. OCT. Pap. Bernice P. Bishop Mus.,
10 (11), pp. 1-11.
1935. Report of C. Montague Cooke, Jr.. Malacologist and Leader,
Mangarevan Expedition. Bull. Bernice P. Bishop Mus.. 133. pp.
36-56.
COOKE, C. MONTAGUE and YOSHIO KONDO
1960. Revision of the Tornatellinidae and Achatinellidae
(Gastropoda, Pulmonata). Bull. Bernice P. Bishop Mus., 221,
303 pp., 123 figs., 2 tables.
Cox, JAMES C.
1870. Descriptions of seventeen new species of land shells from the
South-Sea Islands, in the cabinet of Mr. John Brazier of
Sydney. Proc. Zool. Soc. London, 1870, pp. 81-85.
CRAMPTON, HENRY EDWARD
1916. Studies on the variation, distribution, and evolution of the
genus Partula. The species inhabiting Tahiti. Carnegie Institute
Washington, Pub. 228, 311 pp., 34 pis.
CROSSE, H.
1894. Faune malacologique terrestre et fluviatile de la Nouvelle-
Caledonie et de ses dependances. Jour. Conchyl., 42 (3-4), pp.
161-473, pis. 7-10.
CUMBER, R. A.
1960. Riblet frequency as a taxonomic character in New Zealand
terrestrial Mollusca. Trans. Rov. Soc. N. Z.. «8 m nn QQ.ini
1961. A revision of the genus Phenacohelix Suter 1892 (Mollusca:
Flammulinidae), with description of a new species, and studies
on variation, distribution, and ecology. Trans. Roy. Soc. N. Z., 1
(13), pp. 163-196.
1962. Paleogeographic history reflected in speciation trends of the
New Zealand ribbed pulmonate Charopa coma (Gray)
(Charopidae). Trans. Roy. Soc. N. Z., 1 (30), pp. 365-371.
1964. Regional variation in riblet frequency in the Ptychodon
(Ptychodon) hectori-hunuaensis complex (Mollusca:
Charopidae). Trans. Roy. Soc. N. Z., 4 (10), pp. 161-166.
DELHAYE, W. and J. BOUILLON
1972a. L'evolution et 1'adaptation de 1'organe excreteur chez les
mollusques gasteropodes pulmones. I. Bull. Biol., 106 (1), pp. 45-
79, 14 figs.
1972b. L'evolution et 1'adaptation de 1'organe excreteur chez les
mollusques gasteropodes pulmones. II. Bull. Biol., 106 (2), pp.
123-142, 12 figs.
DELL, RICHARD K.
1955. The land Mollusca of Nissan Island, Solomon Islands. Pac.
Sci., 9, pp. 324-331.
DESHAYES, G.-P.
1851. Histoire Naturelle generale et particulaire des Mollusques
terrestres et fluviatiles, 1.
FERUSSAC, J. P. L. d'A.
1821. Tab. Syst. des Animaux Moll., Part 2, Paris, Arthur
Bertrand; London, G. B. Sowerbv.
1832. Hist. Nat. Moll. terr. fluv., 3.
1840. Histoire naturelle Mollusques terrestres et fluviatiles. Vol. 1,
pp. 90-91, fig. 3, pi. 86. Paris, J. B. Bailliere.
FlSCHER-PlETTK, E.
1950. Liste des Types decrits dans le Journal de Conchyliologie et
conserves dans la Collection de ce Journal. Jour. Conchyl., 90
(2), pp. 65-82.
FRETTER, V. and A. GRAHAM
1962. British Prosobranch Molluscs. London, Ray Society. 755 pp.,
317 figs.
GABRIEL, CHARLES J.
1930. Catalogue of the land shells of Victoria. Proc. Roy. Soc.
Victoria, 43 (1), pp. 62-88, pis. 2-3.
496
SOLEM: ENDODONTOID LAND SNAILS
GARRETT, ANDREW
1872. Descriptions of new species of land and fresh water shells.
Amer. Jour. Conchol., 7 (4), pp. 219-230, pi. 19.
1874. Descriptions of new species of land shells inhabiting the
South Sea Islands. Proc. Acad. Nat. Sci., Phila., 1873, pp. 233-
237.
1879. List of land shells inhabiting Rurutu, one of the Austral
Islands, with remarks on their synonymy, geographical range,
and descriptions of new species. Proc. Acad. Nat. Sci., Phila.,
1879, pp. 17-30.
1881. The terrestrial Mollusca inhabiting the Cook's or Hervey
Islands. Jour. Acad. Nat. Sci., Phila. (2), 8 (4), pp. 381-411.
1884. The terrestrial Mollusca inhabiting the Society Islands. Jour.
Acad. Nat. Sci., Phila., (2), 9 (1), pp. 17-114, pis. 2-3.
1887a. On the terrestrial mollusks of the Viti Islands. Part I. Proc.
Zool. Soc. London, 1887, pp. 164-189.
1887b. The terrestrial Mollusca inhabiting the Samoa or Navigator
Islands. Proc. Acad. Nat. Sci., Phila., 1887, pp. 124-153.
1887c. Mollusques terrestres des lies Marquises (Polynesie). Bull.
Soc. Malacol. France, 4, pp. 1-48.
GERMAIN, Louis
1932. La Faune Malacologique des lies Fidji. Ses caracteres, ses
relations et son origine. Ann. Inst. Oceanogr., n. s., 12 (2), pp. 39-
63, 2 text figs.
1934. Etudes sur les faunes malacologiques insulaires de 1'Ocean
Pacifique. Mem. Soc. Biogeog., 4, pp. 89-153, 4 maps.
GODWIN-AUSTEN, H. H.
1889-1914. Land and freshwater Mollusca of India, including South
Arabia, Baluchistan, Afghanistan, Kashmir, Nepal, Burmah,
Pegu, Tenasserim, Malay Peninsula, Ceylon and other islands of
the Indian Ocean. Vol. 2, 442 pp., pis. 63-158.
GOULD, AUGUSTUS A.
1844. Two species of Helix from the Sandwich Islands. Proc.
Boston Soc. Nat. Hist., 1, p. 174.
1846a. Descriptions of the Species Helix, from the Shells of the
United States Exploring Expedition. Proc. Boston Soc. Nat.
Hist., 2, pp. 170-173.
1846b. Descriptions of the Species Helix, from the Shells of the
United States Exploring Expedition. Proc. Boston Soc. Nat.
Hist., 2. pp. 175-176.
1846c. Expedition shells: described for the work of the United
States Exploring Expedition. Reprinted by Freeman and Bolles,
Boston, pp. 1-200. (Reprinted again in 1862 as Otia
Conchologica)
1852. Mollusca & Shells, Vol. 12, in United States Exploring
Expedition during the years 1838, 1839, 1840, 1841, 1842 under
the command of Charles Wilkes, U. S. N. 510 pp.
1860. Atlas of Shells, in United States Exploring Expedition during
the years 1838, 1839, 1840, 1841, 1842 under the command of
Charles Wilkes, U. S. N. 52 pis.
1862. Otia Conchologica: descriptions of shells and mollusks from
1839 to 1862. Boston, Freeman and Bolles. 256 pp.
GOULD, STEPHEN JAY
1969. An Evolutionary Microcosm: Pleistocene and Recent History
of the Land Snail P. (Poecilozonites) in Bermuda. Bull. Mus.
Comp. Zool., Harv. Coll., 138 (7), pp. 407-531, 26 figs., 3 tables, 5
pis.
1971. The paleontology and evolution of Cerion, II: age and fauna
of Indian shell middens on Curacao and Aruba. Breviora, 372,
pp. 1-26.
GREGORY, H. E.
1936. Report of the Director for 1935. Bull. Bernice P. Bishop
Mus., 140, pp. 1-52.
GUDE, G. K.
1913. The Helicoid land shells of the Fiji Islands, with definitions
of three genera and descriptions of four new species. Proc.
Malacol. Soc. London, 10 (5), pp. 325-330, pi. XIV.
1914. Mollusca. II. (Trochomorphidae-Janellidae). The Fauna of
British India. London, Taylor & Francis. 520 pp., 164 figs.
HEDLEY, CHARLES
1891. The land and fresh-water shells of Lord Howe Island. Rec.
Aust. Mus., 1 (7), pp. 134-144, pis. 21-22.
1893a. Observations on the Charopidae. Part I. Proc. Linn. Soc. N.
S. W., (2), 7, pp. 157-169, pis. 1-2.
1893b. Note on Endodonta (Flammulina) infundibuhtm, Hombr. &
Jacq. Nautilus, 7 (3), p. 35.
HEDLEY, CHARLES and HENRY SUTER
1893. Reference list of the land and freshwater Mollusca of New
Zealand. Proc. Linn. Soc. N. S. W., (2), 7, pp. 613-665.
HOMBRON, M. and H. JACQUINOT
1841. Description de quelques Mollusques provenant de la
campagne de 1'Astrolabe et de la Zelee. Ann. Sci. nat, Serie
Zool., (2), 16, pp. 62-64.
1852. Voy. Pol. Sud, Astrolabe et Zelee. Atlas and text by
Rousseau.
HUTTON, F. W.
1883. Descriptions of new land shells. Trans. Proc. New Zealand
Inst. for 1882, 15, pp. 134-141.
1884a. Notes on some New Zealand land shells, with descriptions
of new species. Trans. Proc. New Zealand Inst. for 1883, 16, pp.
161-186, pis. 9-11.
1884b. Revision of the land Mollusca of New Zealand. Trans. Proc.
New Zealand Inst. for 1883, 16, pp. 186-212.
IHERING, HERMANN VON.
1893. Observations on the helices of New Zealand. Nautilus, 6 (17),
pp. 121-124.
IREDALE, TOM
1913. The land Mollusca of the Kermadec Islands. Proc. Malacol.
Soc. London, 10 (6), pp. 364-388, pi. 18.
1915a. A commentary on Suter's "Manual of the New Zealand
Mollusca". Trans. New Zealand Inst., 47, pp. 417-497.
1915b. A comparison of the land molluscan faunas of the
Kermadec Group and Norfolk Island. Trans. New Zealand Inst.,
47, pp. 498-508.
1933. Systematic notes on Australian land shells. Rec. Aust. Mus.,
19, pp. 37-59.
1937a. A basic list of the land Mollusca of Australia. Aust. Zool., 8
(4), pp. 287-333.
1937b. An annotated check list of the land shells of South and
Central Australia. S. Aust. Nat., 18 (1-2), pp. 6-59, 2 pis.
1937c. A basic list of the land Mollusca of Australia. Part II. Aust.
Zool., 9 (1), pp. 1-39, pis. 1-3.
1939. A review of the land Mollusca of Western Australia. J. R.
Soc. West. Aust., 25, pp. 1-88, pis. 1-5, 1 map.
1941a. Guide to the land shells of New South Wales. Part II.
Austr. Nat., 10 (8), pp. 262-269, figs. 4-6.
1941b. Guide to the land shells of New South Wales. Part III.
Austr. Nat., 11 (1), pp. 1-8, figs. 7-8.
REFERENCES
497
1941c. A basic list of the land Mollusca of Papua. Aust. Zool., 10
(1), pp. 51-94, pis. 3-4.
1942. Guide to the land shells of New South Wales. Part IV. Austr.
Nat., 11 (2), pp. 33-40, figs. 9-11.
1944. The land Mollusca of Lord Howe Island. Aust. Zool., 10 (3),
pp. 299-334, pis. 17-20.
1945. The land Mollusca of Norfolk Island. Aust. Zool., 11 (1), pp.
46-71, pis. 2-5.
JOHNSON, RICHARD I.
1949. Jesse Wedgwood Mighels with a bibliography and a
catalogue of his species. Occ. Pap. Moll., 1 (14), pp. 213-231, pis.
26-27.
1964. The recent Mollusca of Augustus Addison Gould. Bull. U. S.
Nat. Mus., 239, pp. 1-182, 45 pis.
KONDO, Y.
1962. The genus Tubuaia, Pulmonata, Achatinellidae. Bull.
Bernice P. Bishop Mus., 224, pp. 1-49, 8 tables, 14 figs.
KONDO, Y. and W. J. CJLENCH
1952. Charles Montague Cooke, Jr., a bio-bibliography. Bernice P.
Bishop Mus., Spec. Pub. 42, pp. 1-56.
LADD, HARRY S.
1958. Fossil land shells from Western Pacific Atolls. Jour.
Paleontol., 32 (1), pp. 183-198, 5 figs., pi. 30.
1968. Fossil land snail from Funafuti, Ellice Islands. Jour.
Paleontol., 42 (3), p. 857, 1 fig.
LADD, HARRY S., JOSHUA I. TRACEY, and M. GRANT GROSS
1967. Drilling on Midway Atoll. Science, 156 (3778), pp. 1088-1094,
5 figs., 3 tables.
1970. Deep Drilling on Midway Atoll. Geol. Survey Prof. Pap.,
680-A: A1-A22, 20 figs.
LEOPOLD, ESTELLA B.
1969. Miocene pollen and spore flora of Eniwetok Atoll, Marshall
Islands. Geol. Survey Prof. Pap., 260-11, pp. i-iv, 1133-1185, 6
tables, figs. 332-342, pis. 304-311.
LlARDET, E. A.
1876. On the land-shells of Taviuni, Fiji Islands, with descriptions
of the new species. Proc. Zool. Soc. London, 1876 (1), pp. 99-101,
IpL
MIGHELS, J. W.
1845. Descriptions of shells from the Sandwich Islands, and other
localities. Proc. Boston. Soc. Nat. Hist., 2, pp. 18-28.
MOLLENDORFF, OTTO VON
1888. Von den Philippinen. V. Nachr. Bl. deut. Malak. Gesell., 20
(5-6), pp. 65-90.
1890. Die Landschnecken-Fauna der Insel Cebu. Ber. Senckenb.
Naturf. Ges, 1890, pp. 191-295, tables VII-IX.
1895. Pilsbry's neue Eintheilung der Heliciden. Nachr. Bl. deut.
Malak. Gesell., 27 (9-10), pp. 153-165.
1899. Die Phenacoheliciden. Nachr. Bl. deut. Malak. Gesell., 31 (1-
2), pp. 22-25.
1900. The Land Shells of the Caroline Islands. Jour. Malacol., 7
(5), pp. 101-126, 3 figs.
MORCH, O. A. L.
1865. Quelques mots sur un arrangement des Mollusques pulmones
terrestres (Geophiles Fer.) base sur le systeme nature! (suite).
Jour. Conchyl., 13, pp. 376-396.
MORSE, EDWARD S.
1864. Observations on the terrestrial Pulmonifera of Maine,
including a catalogue of all the species of terrestrial and
fluviatile Mollusca known to inhabit the State. Jour. Portland
Soc. Nat. Hist., 1, pp. 1-63, 10 pis.
MOUSSON, ALBERT
1865. Coquilles terrestres et fluviatiles de quelques iles de 1'ocean
Pacifique, recueilles par M. le Dr. E. Graeffe. Jour. Conchyl., 13,
pp. 164-209.
1869. Faune malacologique terrestre et fluviatile des lies Samoa,
publiee d'apres les envois de M. le Dr. E. Graeffe. Jour.
Conchyl., 17, pp. 323-390, pis. 14-15.
1870. Faune malacologique terrestre et fluviatile des lies Viti,
d'apres les envois de M. le Dr. E. Graeffe. Jour. Conchyl., 18, pp.
109-135, 179-236, pis. 7-8.
1871. Faune malacologique terrestre et fluviatile des iles Tonga,
d'apres les envois de M. le Dr. E. Graeffe. Jour. Conchyl., 19, pp.
5-33, pi. 3.
1873. Faune malacologique de quelques iles de 1'ocean Pacifique
occidental. Jour. Conchyl., 21, pp. 101-116, pi. 7.
MULLER, O. F.
1774. Vermium terrestrium et fluviatilium. Vol. 2. Havniae.
PEASE, W. HARPER
1861. Descriptions of new species of Mollusca from the Pacific
Islands. Proc. Zool. Soc. London, 1861, pp. 242-247.
1864. Descriptions of new species of land shells from the islands of
the Central Pacific. Proc. Zool. Soc. London, 1864, pp. 668-766.
1866. Descriptions of new species of land shells, inhabiting
Polynesia. Amer. Jour. Conchol., 2 (4), pp. 289-293, pi. 21, figs. 1-
3.
1867. Scientific intelligence (first paragraph). Amer. Jour.
Conchol., 3, p. 104.
1868. Descriptions of new land shells, inhabiting Polynesia. Amer.
Jour. Conchol., 3, pp. 223-230.
1870. Remarques sur certaines especes de coquilles terrestres,
habitant la Polynesie, et description d'especes nouvelles. Jour.
Conchyl., 18, pp. 393-398.
1871a. Catalogue of the land shells inhabiting Polynesia, with
remarks on their synonymy, distribution and variation, and
descriptions of new genera and species. Proc. Zool. Soc. London,
1871, pp. 449-477.
1871b. Synonymie de quelques genres et especes de coquilles
terrestres habitant la Polynesie. Jour. Conchyl., 19, pp. 92-97.
PFEIFFER, L.
1842. Symbolae ad historian! heliceorum, 2, pp. 1-147.
1845. Uebersicht der mit innern Lamellen versehenen He/ix-Arten.
Zeits. Malak., 2 (6), pp. 81-87.
1846a. Description of fourteen new species of Helix, belonging to
the collection of H. Cuming, Esq. Proc. Zool. Soc. London, 1845,
pp. 123-125.
1846b. V. Diagnoses, specierum novarum vel minus cognitarum.
Symb. ad. hist. Heliceorum, 3 (5), pp. 65-%.
1848. Monog. helic. viv., 1, pp. 1-432.
1850a. Descriptions of twenty-four new species of Helicea, from the
collection of H. Cuming, Esq. Proc. Zool. Soc. London, 1849, pp.
126-131.
1850b. Nachtrage zu L. Pfeiffer Monographia Heliceorum. Zeits.
Malak., 6, pp. 66-79.
1852. Syst. Conch. Cab., Helix, (1), 12 (2), pp. 132, 133, 197-199,
pis. 89, 100.
498
SOLEM: ENDODONTOID LAND SNAILS
1853a. Diagnosen neuer Heliceen, vom Dr. L. Pfeiffer. Zeits.
Malak., 10, pp. 51-58.
1853b. Monog. helic. viv., 3, Lipsiae, F. A. Brockhaus.
1853c. Syst. Conch. Cab., Helix, (1), 12 (3), pp. 293-298, pi. 125.
1856. Descriptions of twenty-five new species of land-shells, from
the collection of H. Cuming, Esq. Proc. Zool. Soc. London, 1856,
pp. 32-36.
1858. Descriptions of eleven new species of land-shells, from the
collection of H. Cuming, Esq. Proc. Zool. Soc. London, 1858, pp.
20-25.
1859a. Descriptions of twenty-seven new species of land-shells,
from the collection of H. Cuming, Esq. Proc. Zool. Soc. London,
1859, pp. 23-32.
1859b. Nachtrage zum zweiten Supplemente meiner Monographia
Heliceorum. Malak. Blatt, 6, pp. 1-14.
1859c. Mon. helic. viv, 4. Lipsiae, F. A. Brockhaus.
1862. Beschreibung neuer landschnecken. Malak. Blatt, 9, pp. 151-
156.
1868. Monog. helic. viv., 5. Lipsiae, F. A. Brockhaus.
1869. Novit. Conchol., 3, pp. 505-506, pi. 108.
1876. Monog. helic. viv., 7. Lipsiae, F. A. Brockhaus.
1877. Syst. Conch. Cab., Helix, (1), 12 (4), p. 554, pi. 166.
PILSBRY, HENRY A.
1892a. Observations on the helices of New Zealand. Nautilus, 6 (5),
pp. 54-57.
1892b. Observations on the helicoid group Charopa and allied
forms. Nautilus, 6 (6), pp. 67-69.
1892c. Manual of Conchology, (2), 8, pp. 1-314, 58 pis.
1893a. Preliminary outline of a new classification of the helices.
Proc. Acad. Nat. Sci., Phila., 1892, pp. 387-404.
1893b. Note upon Dr. v. Ihering's observations. Nautilus, 6 (11),
pp. 129-131.
1893-1895. Manual of Conchology. (2), 9, 366 pp., 71 pis.
1896. The Aulacopoda: a primary division of the monotremate
land Pulmonata. Nautilus, 9 (1), pp. 109-111.
1900a. On the zoological position of Partula and Achatinella, Proc.
Acad. Nat. Sci., Phila., 1900, pp. 561-567, pi. 17.
1900b. The genesis of mid-Pacific faunas. Proc. Acad. Nat. Sci.,
Phila., 1900, pp. 568-581.
1916. Mid-Pacific land snail faunas. Proc. Nat. Acad. Sci., 2, pp.
429-433.
1918. A review of the land mollusks of the Belgian Congo chiefly
based on the collections of the American Museum Congo
Expedition, 1909-1915. Bull. Amer. Mus. Nat. Hist, 40 (1), pp. 1-
370, 23 pis., 163 figs.
1921. The dispersal and affinities of Polynesian land snail faunas.
Proc. 1st Pan-Pac. Sci. Congr., pp. 147-152.
1931. Manual of Conchology, (2), 28, pp. 49-96, pis. 9-12.
1940. Land Mollusca of North America (North of Mexico). Monog.
Acad. Nat. Sci., Phila., no. 3, Vol. 1, Part 2, pp. 575-994, figs.
378-580.
1948. Land Mollusca of North America (North of Mexico). Monog.
Acad. Nat. Sci., Phila.. no. 3, Vol. 2, Part 2, pp. 521-1113, figs.
282-585.
PILSBRY, HENRY A. and C. MONTAGUE COOKE, JR.
1914-1916. Manual of Conchology. Appendix to Amastridae,
Tornatellinidae, (2), 23, 302 pp., pis. 1-55.
PILSBRY, H. A. and E. G. VANATTA
1905. Notes on some Hawaiian Achatinellidae and Endodontidae.
Proc. Acad. Nat. Sci., Phila., 1905, pp. 570-575, pis. 38-39.
1906. New Hawaiian Species of Endodonta and Opens. Proc. Acad.
Nat. Sci., Phila., 1905, pp. 783-786, pi. 43.
PONSONBY, J. H.
1910. Notes on the genus Libera. Proc. Malacol. Soc. London, 9
(1), pp. 37-43.
POWELL, A. W. B.
1957. Shells of New Zealand, an illustrated handbook. 3rd ed.
Whitcombe and Tombs Ltd, pp. 1-202, 36 pis.
QUADRAS, J. F. and O. F. VON MOLLENDORFF
1894. Diagnosis specierum novarum a J. F. Quadras in insulis
Mariannis collectarum scripserunt. Nachr. Bl. deut. Malak.
Gesell., 26 (1-2), pp. 13-22.
RAUP, DAVID M.
1962. Computer as aid in describing form in gastropod shells.
Science, 138, pp. 150-152, 2 figs.
RAVEN, PETER H. and DANIEL I. AXELROD
1972. Plate tectonics and Australasian paleobiogeography. Science,
176 (4042), pp. 1379-1386, 2 figs.
REEVE, LOWELL
1851-1854. Conchologica Iconica, 7, Helix.
RENSCH, BERNHARD
1966. Evolution above the species level. New York, John Wiley
Science Editions. 419 pp., 113 figs.
RENSCH, ILSE
1937. Systematische und Tiergeographische Untersuchungen iiber
die Landschneckenfauna des Bismarck- Archipels. II. Archiv.
Naturgeschichte, N. F., 6 (4), pp. 526-644, 54 figs.
RlGBY, J. E.
1963. Alimentary and reproductive systems of Oxychilus cellarius
(Muller) (Stylommatophora). Proc. Zool. Soc. London, 141 (2),
pp. 311-359, 18 figs., 3 tables.
1965. Succinea putris: a terrestrial opisthobranch mollusc. Proc.
Zool. Soc. London, 144 (4), pp. 445-486, 11 figs., 1 plate.
ROUSSEAU, L.
1854. See Hombron and Jacquinot (1852)
RUNHAM, N. W.
1969. The use of the scanning electron microscope in the study of
the gastropod radula: the radulae of Agriolimax reticulatus and
Nucella lapillus. Proc. Third Europ. Malac. Congr.,
Malacologia, 9 (1), pp. 179-185, 7 figs.
ST. JOHN, HAROLD
1940. Itinerary of Hugh Cuming in Polynesia. Occ. Pap. Bernice P.
Bishop Mus., 16 (4), pp. 81-90, 1 fig.
SCHMELTZ, O.
1874. Cat. Mus. Godeffroy, 5.
1877. Cat. Mus. Godeffroy, 6.
SEMPER, C.
1874. Landmollusken. In Reisen im Archipel der Philippinen (2), 3,
pp. 129-168.
SMITH, EDGAR A.
1892. On the land-shells of St. Helena. Proc. Zool. Soc. London,
1892, pp. 258-270, pis. 21-22.
REFERENCES
499
1893. Descriptions of two new species of Patula from St. Helena.
Conchologist, 2 (7), pp. 164-165, 3 figs.
1897. On a collection of land and freshwater shells from Rotuma
Island. Ann. Mag. Nat. Hist., (6), 20, pp. 519-523.
SOLEM, ALAN
1957. Philippine snails of the family Endodontidae. Fieldiana:Zool.,
42 (1), pp. 1-12, 4 figs.
1958. Endodontide Landschnecken von Indonesien und Neu
Guinea. Arch. Molluskenkd., 87 (1-3), pp. 19-26, pi. 3, 1 table.
1959a. Systematics and Zoogeography of the Land and Fresh-
water Mollusca of the New Hebrides. Fieldiana:Zool., 43, pp. 1-
359, 38 figs., pis. 1-34.
1959b. On the family position of some Palau, New Guinea, and
Queensland land snails. Arch. Molluskenkd., 88 (4/6), pp. 151-
158, 2 figs., pis. 12-13.
1960. Non-marine Mollusca from the Florida Islands, Solomon
Islands. J. Malacol. Soc. Aust., 4, pp. 39-56, pis. 4-6.
1961. New Caledonian land and fresh-water snails, an annotated
check list. Fieldiana:Zool., 41 (3), pp. 415-501, figs. 1-14.
1964. Amimopina, an Australian enid land snail. Veliger, 6 (3), pp.
115-120, 4 figs.
1966a. Some non-marine mollusks from Thailand, with notes on
classification of the Helicarionidae. Spolia Zool. Mus.
Hauniensis, 24, pp. 1-108, 24 figs., pis. 1-3.
1966b. The neotropical land snail genera Labyrinthus and
Isomeria (Pulmonata, Camaenidae). Fieldiana: Zool., 50, pp. 1-
226, 61 figs.
1969a. Abundance, local variation and brood pouch formation in
Libera fratercula from Rarotonga, Cook Islands. Amer.
Malacol. Union, Ann. Repts., 1968, pp. 10-12, 3 figs.
1969b. Phylogenetic position of the Succineidae. Proc. Third
Europ. Malacol. Congr., Malacologia, 9 (1), p. 289.
1969c. Basic distribution of nonmarine mollusks. Marine Biological
Association of India, Symposium on Mollusks, Part I, pp. 231-
247, 10 figs.
1970a. The endodontid land snail genera Pilsbrycharopa and
Paryphantopsis. Veliger, 12 (3), pp. 239-264, 3 figs., 6 tables.
1970b. Malacological applications of scanning electron microscopy
I. Introduction and shell surface features. Veliger, 12 (4), pp.
394-400, pis. 58-60.
1970c. The land snail genus Afrodonta (Mollusca:Pulmonata:
Endodontidae). Ann. Natal. Mus., 20 (2), pp. 341-364, 2 figs., 3
tables.
1972a. Malacological applications of scanning electron microscopy
II. Radular structure and function. Veliger, 14 (4), pp. 327-336, 4
pis.
1972b. Tekoulina, a new tornatellinid land snail from Rarotonga,
Cook Islands. Proc. Malacol. Soc. London, 40 (2), pp. 93-114, 3
figs., 3 pis., 1 table.
1972c. Microarmature and barriers in the apertures of land snails.
Veliger, 15 (2), pp. 81-87, 5 pis.
1973a. Convergence in pulmonate radulae. Veliger, 15 (3), pp. 165-
171, 4 pis.
1973b. Apertural barriers in Pacific Island land snails of the
families Endodontidae and Charopidae. Veliger, 15 (4), pp. 300-
306, 7 pis.
1973c. Craterodiscus, a camaenid land snail from Queensland.
Jour. Malacol. Soc. Aust., 2 (4), pp. 377-385, 1 fig., 6 pis.
1973d. A new genus and two new species of land snails from the
Lau Archipelago of Fiji. Veliger, 16 (1), pp. 20-30, 3 pis., 6 figs.
1974. The Shell Makers: Introducing Mollusks. John Wiley &
Sons, New York. 289 pp.
1975. Polygyriscus virginianus (Burch, 1947) a helicodiscid land
snail (Pulmonata: Helicodiscidae). Nautilus, 89 (3), pp. 80-86, 8
figs.
In Press A. Mollusca. Charopidae. La Faune Terrestre de 1'ile de
Sainte-Helene. Ann. Mus. R. Afr. Cent.
In press B. Classification of the Land Mollusca. Symposia of the
Zoological Society of London and the Malacological Society of
London^
SOLEM, ALAN and ELLIS H. YOCHELSON
In press. North American Paleozoic land snails, with a summary of
other Paleozoic non-marine snails. U.S. Geol. Surv., Prof. Pap.
SUTER, HENRY.
1890. Descriptions of new species of New Zealand land and fresh-
water shells. Trans. Proc. New Zealand Inst., 22, pp. 221-230,
pis. 14-15.
1891a. Descriptions of new species of New Zealand land and fresh-
water shells. Trans. Proc. New Zealand Inst., 23, pp. 84-93, pis.
16-18.
1891b. Miscellaneous communications on New Zealand land and
fresh-water Mollusca. Trans. Proc. New Zealand Inst., 23, pp.
93-96, pis. 17-18.
1892a. Contributions to the Molluscan fauna of New Zealand.
Trans. Proc. New Zealand Inst., 24, pp. 270-278.
1892b. Miscellaneous communications on New Zealand land and
freshwater Mollusca. Trans. Proc. New Zealand Inst, 24, pp.
283-286.
1892c. On the dentition of some New Zealand land and freshwater
Mollusca, with descriptions of new species. Trans. Proc. New
Zealand Inst., 24, pp. 286-303, pis. 20-23.
1893a. Preliminary notes on Tasmanian land snails. Nautilus, 7
(7), pp. 77-78.
1893b. Contributions toward a revision of the Tasmanian land
Mollusca. Nautilus, 7 (8), pp. 87-90.
1893c. Liste synonymique et bibliographique des Mollusques
terrestres et fluviatiles de la Nouvelle-Zelande. Jour, de
Conchyl., 41 (4), pp. 220-293, pi. 9.
1893d. Contributions to the molluscan fauna of New Zealand.
Trans. Proc. New Zealand Inst. for 1892, 25, pp. 147-153.
1894a. Preliminary notes on the relation between the Helicidae of
New Zealand, Tasmania and South Africa. Ann. Mag. Nat.
Hist., (6), 13, pp. 61-65.
1894b. Further contributions to the knowledge of the molluscan
fauna of New Zealand, with descriptions of eight new species.
Trans. Proc. New Zealand Inst., 26, pp. 121-138, pis. 14-21.
1894c. Checklist of the New Zealand land and fresh-water
Mollusca. Trans. Proc. New. Zealand Inst., 26, pp. 139-154.
1894d. Additions and emendations to the reference list of the land
and freshwater Mollusca of New Zealand. Proc. Linn. Soc. N. S.
W., 18 (4), pp. 484-502, pis. 22-23.
1901. Further contributions to the geographical distribution of the
New Zealand non-marine Mollusca. Trans. Proc. New Zealand
Inst., 33, pp. 151-152.
1903. On a new genus and species of the family Phenacohelicidae.
Jour. Malacol., 10 (2), pp. 62-64, pi. 4.
1913. Manual of the New Zealand Mollusca. Wellington,
Government Printer. 1,120 pp., 72 pis.
SYKES, E. R.
1896. Preliminary diagnoses of new species of non-marine Mollusca
from the Hawaiian Islands. Part I. Proc. Malacol. Soc. London,
2, pp. 126-132.
500
SOLEM: ENDODONTOID LAND SNAILS
1900. Mollusca. In Fauna Hawaiiensis, 2 (4), pp. 271-412, pis. 11-12.
TAPPARONE-CANEFRI, C.
1883. Fauna Malacologica della Nuova Guinea e delle isole
adiacenti. Parte I. Molluschi estramarini. Ann. Mus. Civ. Stor.
Nat. 'Giacomo Doria,' (1), 19, pp. 1-313, 7 figs., pis. 1-11.
TAYLOR, D. W. and N. F. SOHL
1962. An outline of gastropod classification. Malacologia, 1(1), pp.
7-32.
THIELE, JOHANNES
1931. Handbuch der Systematischen Weichtierkunde. Zweiter Teil.
pp. 377-778, figs. 471-783.
TRYON, GEORGE W.
1866. Monograph of the terrestrial Mollusca of the United States.
Amer. Jour. Conchol., 2 (3), pp. 218-277, pis. 1-4.
1887. Manual of Conchology, (2), 3, pp. 1-313, 63 pis.
VAN MOL, JEAN-JACQUES
1972. Notes anatomiques sur les Bulimulidae (Mollusques,
Gasteropodes, Pulmones). Ann. Soc. Roy. Zool. Belg., 101 (3),
pp. 183-225, 19 figs.
VON MARTENS, EDUARD
1860. (Edited by). Die Heliceen nach naturlicher verwandtschaft
systematisch geordnet von Joh. Christ. Albers. Zweite Ausgabe,
pp. 1-312.
WAGNER, A. J.
1927. Studien zur Mollusken fauna der Balkenhalbinsel mit
besonderer Berucksichtigung Bulgarians und Thraziens, nebst
monographischer Bearbeitung einzelner Gruppen. Ann. Zool.
Mus. Polon. Hist. Nat., 6, pp. 263-399, pis. 10-22.
WELCH, D'ALTE A.
1938. Distribution and variation of Achatinella mustelina Mighels
in the Waianae Mountains, Oahu. Bull. Bernice P. Bishop Mus.,
152, 164 pp., 13 pis., 16 maps, 38 tables.
WILSON, E. O. and R. W. TAYLOR
1967. The ants of Polynesia. Pacific Insects, Monog., 14, pp. 1-109,
83 figs., 3 tables.
ZILCH, ADOLF
1959-1960. Gastropoda: Euthyneura. In Handbuch der
Palaozoologie. Band 6, Teil 2, Lief, 1-4, 834 pp., 2,515 figs.
ZIMMERMAN, E. C.
1938. Cryptorhynchinae of Rapa. Bull. Bernice P. Bishop Mus.,
151, pp. 1-75, 6 figs., 4 pis., 2 tables.
1948. Insects of Hawaii, vol. 1. Introduction. University of Hawaii
Press. 206 pp., 52 figs.
APPENDIX
Explanation of anatomical abbreviations used on illustrations.
A - anus
B - buccal mass
BE - esophagus
BGN - buccal ganglion
BR - buccal retractor
CR - columellar retractor
DG - prostate
DP - vas opening into penis or epiphallus
E - epiphallus
EP - pore from epiphallus into penis
F - foot
FS - foot grooves
G - ovotestis
GD - hermaphroditic duct
GG - albumen gland and ducts
GT - talon
H - heart
HG - hindgut or rectum
HV - principal pulmonary vein
I - intestine
IZ - stomach
K - kidney
KD - ureter
KX - ureteric pore
LP - pneumostome
MC - mantle collar
MD - mantle retractor muscle
MG - mantle glands
OG - salivary glands
OGD - salivary gland ducts
P - penis
PP - penial stimulator, papilla or pilaster
PR - penial retractor muscle
S - spermathecal shaft and its sac
TE - ommatophores
TV - rhinophoral tentacle
UT - uterus
UTi- section of uterus
UTa- section of uterus
UT:t- section of uterus
\JTt- section of uterus
UV - free or post-uterine oviduct
V - vagina
VD - vas deferens
X - carrefour
Y - genital atrium
Z - digestive gland or liver
501
INDICES
Two indices are presented, a geographic and a syste-
matic. The geographic lists every reference to that unit
in the monograph, without differentiating between
description, discussion, and biogeographic content.
The systematic index discriminates between mention
in a table, distribution figure, or text (Roman type);
illustration of shell, anatomy, or in a graph or diagram
(italics); and the principal systematic discussion (bold
face). In the systematic index, to save space, cross-
referencing is limited to the principal systematic dis-
cussion for species reviewed in this monograph.
Systematic Index
Aaadonta 23, 36, 37, 40, 47, 51, 52, 54,
56-59, 61, 65, 67-69, 71, 73, 76, 79-
81, 83, 85, 87, 94, 95, 99, 110-112,
114, 116, 120, 121, 124, 125, 255,
289, 444, 456, 465, 466, 467-
487, 489, 490
anguarana 114, 116, 124, 444, 467-
470, 472, 473, 474, 476, 483-484,
485
constricta babelthuapi 114, 124, 469,
470, 472, 473, 474, 476-478, 476,
485
constricta constricta 38, 39, 75, 76,
77, 78, 81, 86, 87, 114, 116, 124,
458, 467-470, 471, 472, 473, 474-
476, 475, 478, 481, 483-485, 486,
487
constricta komakanensis 114, 124,
469, 470, 472, 473, 474, 476, 478,
485
fuscozonata 20, 57, 76, 81, 86, 87, 94,
96, 467, 468, 470, 479-482
fuscozonata depressa 114, 124, 445,
467-470, 472-474, 479, 480, 481-
482, 483, 485
fuscozonata fuscozonata 75, 114,
116, 124, 468-470, 471, 472-474,
479, 479-481, 480, 482-485
irregularis 114, 116, 124, 445, 467-
470, 472, 473, 474, 475, 483, 484,
485
kinlochi 75, 81, 114, 124, 336, 444,
445, 467-470, 472, 473, 474, 481,
483, 484-487, 486
pelewana 52, 114, 116, 124, 444, 467-
470, 472, 473, 479, 481, 482, 482-
483,484,485
acetabulum, Nesodiscus var. 354-358
Achatinellidae 1, 5
acuticosta, Mautodontha (Garretto-
concha 1176-178
Aeschrodomus stipulata 74
agakauitaiana, Gambiodonta 431-434
alata, Zyzzyxdonta 466-467
Allodiscus dimorphus 75, 93
Allogona 14
alternata, Anceyodonta 192
altiapica, Opanara 248-249
Amastridae 1
Amphidoxa 118
Amphidoxinae 105
analogica, Taipidon 328-330
anatonuana, Minidonta 140-141
anceyana, Taipidon 327-328
Anceyodonta 19, 39, 48, 51, 54, 57, 61-
63, 67-69, 71-73, 110-112, 119-123,
125-128, 134, 148, 150, 178-207,
213, 242, 289, 290, 315, 318, 344,
345,431,434,489
alternata 57, 122, 178-181, 184-186,
188, 190, 191, 192, 196, 210, 336,
431
andersoni 48, 57, 122, 179, 180-182,
184-186, 188, 190, 191-192, 196,
199,210,344,431
constricta 122, 178-182, 184-186, 188,
189-191 190, 261
densicostata 65, 123, 179-181, 183-
186, 195, 197,199,200, 201
difficilis 51, 53, 54, 58, 122, 178-182,
184-186, 192-195, 793, 794, 795,
196,199,201,203,344,431
ganhutuensis 51, 122, 133, 178-182,
184, 185, 186-188, 787, 197, 344,
468
hamyana 65, 123, 179-181, 183-186,
188, 197, 201, 204-206,205, 344
labiosa 53, 58, 65, 123, 179-181, 183-
186, 197, 199,200, 204,206,431
obesa 51, 54, 57, 123, 179-181, 183-
186, 192, 795, 197, 199, 207, 201-
204,202, 206, 244, 344, 393
sexlamellata 51, 52, 57, 122, 179-182,
184-186, 196-199, 797, 199, 206,
344, 468
soror 51, 53, 54, 58, 122, 179-182,
184-186, 191, 192, 793, 794, 795,
195-196, 199,431
subconica 51, 54, 122, 178-182, 184-
186, 787, 188-189, 196, 344, 431
andersoni, Anceyodonta 191-192
angaurana, Aaadonta 483-484
Antonella trochlearis 273
Anthracopupa 488
aoraiensis, Mautodontha (M. ) 162
apiculata, Endodonta 376-377
arborea, Freycinetia 390
areaensis areaensis, Opanara 241-244
densa, Opanara 244-245
microtorma, Opanara 245-246
Opanara 239-246
Arionacea 104
Arionidae 106
Assimineidae 1, 2
asteriscus, Kondoa 467
atanuiensis, Rhysoconcha 262-264
Athoracophoridae 103
aukenensis, Gambiodonta pilsbryi
436-438
Aulacopoda 103, 104, 105, 107
Australdonta 26, 33, 37, 52, 54, 57, 58,
61, 62, 65, 67-69, 71-76, 80-83, 86,
94, 96, 110-113, 120, 121, 123, 125-
128, 141, 146, 151, 153, 154, 156,
159, 161, 207, 210, 276, 277, 289-
314, 336, 389, 489, 490
degagei 53, 54, 64, 65, 67, 86, 123,
125, 284, 289-292, 293, 294, 296,
297, 298-302, 302, 303, 304
ectopia 47, 62, 111, 113, 123, 289-292,
294,306,311,312-314,373
magnasulcata 123, 289-292, 294,295,
304-306, 467, 468
pharcata 37, 47, 50, 111, 113, 123,
289-292, 294, 311-312, 373
pseudplanulata 52, 65, 67, 123, 276,
289-292, 294-296,295, 299
radiella radiella 53, 54, 57, 62, 123,
249, 276, 289-292, 294, 299, 305,
306-307,309,311,314,332
radiella rurutuensis 123, 290, 291,
294,305, 307
raivavaeana 31, 33, 34, 37, 57, 65, 86,
123, 210, 276, 289, 290, 291, 292,
293, 294, 298, 299, 304, 307-310,
308, 309, 370, 311, 372, 314
rimatarana 123, 289-292, 294, 296-
298,297, 299,302, 303, 304
tapina 65, 123, 289, 291, 292, 294,
296, 298, 299, 307, 302, 302-304,
303, 306
tubuaiana 123, 276, 290-292, 294,
298,299,308,311,372
yoshii 65, 123, 289-292, 294, 296,
299,307, 302,304,306
502
INDEX
503
babelthuapi, Aaadonta constricta 476-
478
baldwini, Nesophila 367
Basommatophora 102, 103
bilamellata, Helix 273
binaria, Endodonta 376
bitridentata, Opanara 235-238
boholensis, Enteroplax 451
boraborensis, Mautodontha (M. ) 156-
157
Bulimulidae 75, 77, 85
bursatella, Libera 393-399
bursatella, Libera 394-397
orofenensis, Libera 397-398
caliculata, Opanara 246-247
callimus, Kleokyphus 224-226
Camaenacea 85
Camaenidae (camaenid) 30
capillata, Nesophila 367-368
Carychium 50, 105
Caryodidae 103
cavernula, Libera 385, 417, 426
celsus, Nesodisus obolus var. 354-358
centadentata, Taipidon 331-333
Cerion 19
Cerionidae 103
ceuthma, Mautodontha (M. ) 158-159
Chanomphalus 106
Charopa 106, 1 18
vicaria 74
Charopidae (charopid) 1, 2, 3, 4, 5, 9,
10, 19, 24, 30, 31, 33, 36, 37, 39, 42,
44, 49, 53, 63, 65, 73-79, 81, 83-85,
87, 92-94, 97, 98, 100, 103-108, 119,
121, 125-127, 318, 448, 467, 468,
488, 489
Clausiliidae 103
coarctata, Libera 385, 389, 406, 407
concava, Planudonta 340-342
concentrate, Endodonta 379
consimilis, Mautodontha (Garretto-
concha) 174-176
consobrina, Mautodontha (Garretto-
concha) 165-166
constricta, Aaadonta constricta 474-
476
Anceyodonta 189-191
babelthuapi, Aaadonta 476-478
constricta, Aaadonta 474-478
komakanensis , Aaadonta 478
contortus, Cookeconcha 214-215
cookeana, Libera 400-402
Cookeconcha 3, 17, 26, 36, 39, 48, 49,
54, 56, 58, 60-62, 65, 67-69, 71-74,
76, 79, 81, 83, 85, 86, 92-95, 99, 100,
107, 110-112, 118, 120, 121, 123,
125, 137, 207-224, 289, 363, 365,
366, 371, 375, 376, 390, 465, 488,
489
contortus 123, 207, 208, 210, 211,
214-215,216
cookei 57, 111, 123, 207, 208, 210,
213,214
decussatulus 34, 36, 40, 62, 123, 207,
210,211,221,222,336,344
elisae!23, 207, 210, 216
henshawi 56, 111, 116, 123, 207, 208,
210-212,213,214,215,371
hystricellus 74, 79, 92, 93, 123, 207,
208, 210, 215, 216-217, 218, 220,
336, 374
hystrix 34, 40, 62, 92, 123, 207, 209-
211, 220-221, 222, 367, 368
jugosus 47, 49, 62, 74, 75, 78, 80, 87,
92, 93, 123, 207, 209-211, 221-
224,336,344,374
lanaiensis 62, 123, 207, 209-211, 221,
222, 336, 344
luctiferus 123, 207, 208, 210, 216,279
nudus 40, 56, 66, 111, 112, 123, 207,
208,210,213,214,215
paucicostatus 62, 123, 207, 209, 210,
211,218-219,220
paucilamellatus 123,211,219
ringens 123, 207, 208, 210, 214, 215-
216, 336
stellulus 123, 207, 209, 210, 217-218,
218, 336,371,467,468
subpacificus 111, 112, 116, 117, 123,
125, 207, 208, 210, 211-212, 212,
468, 488
thaanumi 62, 123, 207, 209, 211,219,
219-220
thwingi 56, 111, 123, 207, 208, 210,
213-214,215
cookei, Cookeconcha 213
cookei, Orangia 281-285
montana, Orangia 285-286
Orangia 279-287
tautautuensis, Orangia 286-287
Corillidae 53, 102
corrugata, Thaumatodon 463-464
Coxia 95
m. macgregori 95
Craterodiscus 75
cretaceus, Nesodiscus 358-360
daedalea, Mautodontha (M. ) 157-158
davidi, Ptychodon 116, 118
decemplicata, Thaumatodon 451-453
decollata, Rumina 95
decora, Taipidon petricola 322-324
decorticata formotareae, "Patula" 162
decussatulus, Cookeconcha 221
degagei, Australdonta 298-302
Dendrotrochus 105
densa, Opanara areaensis 244-245
densicostata, Anceyodonta 199
depasoapicata, Opanara 233-235
depressa, Aaadonta fuscozonata 481-
482
Diastole glaucina 135
difficilis, Anceyodonta 192-195
dimidiata, Otoconcha 106
dimorphus, Allodiscus 75, 93
Diplommatina 43
Diplommatinidae 1, 2, 31
Dipnelicidae 105
Discinae 105
Discocharopa 125, 126, 344
Discus 50, 105, 118
rotundatus 199
distans, Nesophila 367
Dorcasiidae 103
dubiosa, Libera 406-407
duplicidentata. Opanara 238-239
ectopia, Australdonta 312-314
ekahanuiensis. Endodonta 375-376
Electrina succinea 273
elisae, Cookeconcha 216
Ellobiidae 102, 104, 105
Endodonta 2, 3, 8, 10, 26, 39, 47, 48, 54,
56, 57, 59, 61, 62, 65, 67-69, 71-73,
78, 80-83, 85, 86, 92, 94, 96, 106,
110-112, 118, 119, 121, 124-126,
137, 207, 210, 217, 224, 285, 289,
349, 365, 366, 370, 371-383, 386,
389, 426, 444, 468, 489
acuticarinata 345
apiculata 124, 371, 376-377
6/naria 37, 48-50, 56, 61, 124, 368-
371,375,376,377
concentrata 46, 56, 124, 370, 371, 379
ekahanuiensis 26, 50, 56, 124, 370,
371,375-376,375
fricki 46, 52, 56, 66, 74, 76, 84, 87, 90,
94, 124, 222, 239, 255, 310, 365,
366, 370, 371, 372, 373, 375, 379,
380, 381-383, 426, 456, 476
garrettii 351, 352, 354
incertaS, 111
kamehameha 29, 46, 124, 370, 371,
377-378, 379
lamellosa 46, 56, 68, 86, 90, 124, 370,
371, 374, 375, 378-380, 381, 382
laminata 46, 50, 124, 370, 371, 375,
377, 382
marsupialis 28, 46, 56, 68, 90-92,
111, 113, 124, 370, 371, 375, 378,
379,380-381,386
rugata 124,371,377
Enidae(enids) 103
eniwetokensis, Ptychodon 116
Enteroplax boholensis 451
Epiglypta 105
euaensis, Thaumatodon 456-458
Euconulinae 92, 97, 105
Euthyneura 102
excavata, Helix 430
extraria, Minidonta 150-151
Eyryomphala 118
fabrefactus, Nesodiscus 363-364
var.piceus, Nesodiscus 364
fictus, Nesodiscus 360-363
filicostata, Pitys 218
Flammulina (flammulinids) 79, 92,
106, 118
Flammulinidae 105-107
fosbergi, Opanara 251-253
fragila. Taipidon 334-335
fratercula. Libera 418-426
fratercula, Libera 419-425
rarotongensis, Libera 425-426
Freycinetia 100, 465
arborea 390
fricki, Endodonta 381-383
fuscozonata, Aaadonta 479-482
Aaadonta fuscozonata 479-481
depressa, Aaadonta 481-482
fuscozonata, Aaadonta 479-481
Gambiodonta 10, 27, 28, 32, 33, 39, 47,
48, 54, 57, 58, 60-63, 67-69, 71-73,
110-113, 119, 121, 124, 125, 184,
186, 192, 289, 330, 331, 344, 381,
383, 384, 386, 431-444, 468, 489
agakauitaiana 31,32, 34, 37, 39, 124,
185, 431-433, 434-435, 435, 438,
441,443
grandis 24, 39, 47, 49, 54, 60, 124,
184, 185, 365, 385, 418, 431-434,
438,441-444,442
504
SOLEM: ENDODONTOID LAND SNAILS
mangarevana 124, 185, 344, 431-434,
435, 436, 438-440, 441, 443
mirabiUs 32, 49, 124, 184, 185, 218,
431-434, 436, 438, 439, 440-441,
443
pilsbryi 436, 439
pilsbryi aukenensis 124, 185, 431,
432, 433, 434, 436-438, 437, 443
pilsbryi pilsbryi 124, 185, 431-434,
436, 437, 438, 439, 441, 443
tumida 49, 57, 124, 185, 431-434, 436,
438,439,441,443
ganhutuensis, Anceyodonta 186-188
Garrettia 385
garrettiana, Libera 410
garrettii, Endodonta 351, 352, 354
Garrettina 119,385
Garrettoconcha 110, 111, 112, 114, 151,
153, 154,156,162-178,227
glaucina, Diastole 135
globosum, Lamellouum 273
Goniodiscinae 105
grandis, Gambiodonta 441-444
gravacosta, Minidonta 137-139
gregaria, Libera 402-403
hamyana, Anceyodonta 204-206
haplaenopla, Minidonta 143-146
Haplogona 106
Hedleyoconchidae 105, 107
Helenoconcha 63, 118
minutissima 151
Helicacea 85
Helicidae(helicid) 104
Helicarionidae (helicarionids) 1, 9, 79,
92, 104,107,448
Helicarioninae 97, 105
Helicinidae 1
Helicodiscinae 105, 106
Helix 118
bilamellata 273
excavata 430
intercarinata 215
opanica 271
oparica 271
rubiginosa 220, 222
setigera 220
Helminthoglyptidae ( helminthogly-
ptid) 104
hendersoni, Minidonta 134-135
Tubuaia 135
henshawi, Cookeconcha 213
Heterurethra 103
heynemanni, Libera 415
Hiona orbis 273
Holopoda 103-105
Holopodopes (holopodopid) 85, 103,
104
huaheinensis, Nesodiscus 354
Hymenolepis 309
hypsus, Kleokyphus 226-227
hystricellus, Cookeconcha 216-217
hystricoides, Thaumatodon 453-456
hystrix, Cookeconcha 220-221
imperforata, Mautodontha (Garretto-
concha) 170-171
incerta, Endodonta 8
incognata, Libera 417
inexpectans, Minidonta 132
inexpectans, Ptychodon 132
insolens, Rikitea 344-345
intercarinata, Helix 215
intermedia, Planudonta 339-340
irregularis, Aaadonta 483
jacquinoti, Libera 417-418
janeae, Patula 351
jugosus, Cookeconcha 221-224
kamehameha, Endodonta 377-378
kinlochi, Aaadonta 484-487
Kleokyphus 39, 58, 61, 68, 69, 71, 73,
110-113, 116, 117, 119-121, 123,
126, 224-227, 384, 489
callimus 28, 48, 68, 117, 123, 223,
224-226,225
hypsus 29, 47, 49, 50, 117, 123, 223,
224,225,226-227,349
koarana, Ruatara 266-267
komakanensis, Aaadonta constricta
479-482
Kondoa asteriscus 467
Kondoconcha 54, 61, 68, 69, 71, 73,
110-113, 115, 120, 121, 124, 126,
232, 239, 368-371, 490, 491
othnius 28, 46, 49, 69, 73, 80, 115,
124, 236, 255, 257, 368-371, 369,
376, 386
labiosa, Anceyodonta 204
Labyrinthus 53
laddi, Thaumatodon 464-465
lamellosa, Endodonta 378-380
Lamellouum globosum 273
laminata, Endodonta 377
lanaiensis, Cookeconcha 221
Laoma 106, 118
Laominae 105, 106
Libera 7, 8, 13, 17, 27, 28, 39, 47, 48, 51,
53, 54, 56, 58-69, 71, 73-76, 80, 83,
85, 87, 95, 96, 110-114, 118, 119,
121, 124, 126, 151, 162, 165, 210,
330, 331, 351, 381, 383, 384, 385-
431,434,489
bursatella 8, 67, 385, 386, 387, 388,
389, 393-399, 405, 417, 431, 465
bursatella bursatella 10, 37, 41, 49,
67, 81, 82, 86, 87, 100, 124, 162,
387, 388-393, 394-397, 396, 398,
400, 402, 403
bursatella orofenensis 14, 67, 81,
124, 386, 388-395, 397-398, 403
cauernu/a385,417, 426
coarctata 385, 417, 426
coarctata 385, 389, 406, 407
cookeana 15, 48, 49, 81, 82, 84, 95,
124, 385, 386, 388-394, 399, 400-
402, 407
dubiosa 124, 226, 385-392, 406, 406-
407, 408, 409, 415, 430, 468
fratercula 12, 13, 29, 49, 85, 92, 95,
100, 165, 385-390, 418, 419-426,
430,451
fratercula fratercula 49-, 86, 94, 124,
385, 388, 391, 392, 419-425, 422,
426
fratercula rarotongensis 42, 49, 50,
88, 90, 124, 385, 388, 391, 392,
399, 419, 421, 422, 423, 425-426,
428
garrettiana 37, 39, 46, 67, 124, 385,
386, 387, 389, 390, 392, 407, 408,
409, 410, 430, 468
gregaria 28, 49, 56, 124, 385-394, 398,
402-403,404, 405, 409, 415
heynemanni 46, 67, 124, 224, 385-
387, 389, 390, 392, 407-410, 415,
476,430,431
incognata 49, 67, 124, 349, 385-392,
395, 400, 409, 415, 476, 417, 418,
419
jacquinoti 49, 67, 124, 349, 365, 385-
392, 474, 417-418, 419, 429, 444
micrasoma 15, 56, 77, 81, 82, 87, 124,
385-390, 391-393, 394, 395, 407,
412
recedens 8, 28, 49, 50, 51, 124, 385-
388, 389, 390-394, 398, 402, 403-
405, 404, 405, 409, 413, 415
retunsa 50, 56, 62, 124, 385-388, 391,
392, 409, 477, 412-413, 414, 415,
sculptilis 419
spuria 46, 67, 124, 385, 387, 389, 390,
392, 407-410, 408, 409, 410, 468
streptaxon 28, 29, 49, 50, 51, 124,
349, 385-392, 395, 409, 412, 413-
415,474,475
subcavernula 47, 49, 67, 124, 385-
387, 389-392, 417-419, 425, 426-
428,427,429
tumuloides 8, 46, 49, 56, 67, 124, 385-
387, 389, 390, 392, 413, 419, 425,
427, 428-430
turricula 385
umbilicata 37, 56, 124, 385-388, 390-
393,395,398,410-412,477
lidgbirdi, Pseudocharopa 93
lillianae, Pseudolibera 384-385
Limacacea 85, 95, 104, 105, 107
limacid 106
luckmanii, Planilaoma 85
luctiferus, Cookeconcha 216
m. macgregori, Coxia 95
macgregori, Coxia m. 95
magnificus, Nesodiscus 364-365
maituatensis, Orangia 287-288
mangarevana, Gambiodonta 438-440
magnasulcata, Australdonta 304-306
manuaensis, Minidonta 130-132
Maoriconcha 79
marquesana, Taipidon 326
marsupialis, Endodonta 380-381
mastersi, Mystivagor93
matauuna, Planudonta 342
maupiensis, Mautodontha (Garretto-
concha) 166-168
Mautodontha 17, 26, 39, 54, 56, 58, 61-
63, 67-69, 71-73, 79, 80, 81, 84, 109-
114, 116, 117, 119, 120-122, 125-
128, 136, 151-178, 224, 226, 227,
256, 277, 315, 318, 345, 349, 371,
386, 387, 434, 489, 493
(Garrettoconcha) acuticosta 62, 65,
122, 151, 154, 156, 162-165, 174,
775,776, 176-178,777, 178
(M. ) aoraiensis 36, 37, 53, 54, 62, 82,
83, 117, 122, 736, 151, 153-156,
760, 162, 174, 177,336,397
(Af. ) boraborensis 47, 67, 111, 114,
117, 119, 122, 126, 151, 752, 153-
155, 156-157, 164, 224, 226, 345,
371
INDEX
505
(M. ) ceuthma 52, 111, 113, 117, 122,
125, 128, 151, 152, 153-156, 158-
159,315
(Garrettoconcha) consimilis 62, 65,
117, 122, 151, 154, 162-165, 174-
176,775,776,777, 178
(Garrettoconcha) consobrina 111,
122, 126, 151, 153, 154, 163, 165,
166, 767, 168, 224, 315, 386, 387,
446, 448
(Af.) daedalea 65, 73, 117, 122, 126,
146, 150, 151, 153-155, 757, 157-
158,159,164,224,387
(Garrettoconcha) imperforata 53,
117, 122, 127, 139, 151, 153, 154,
163-165, 168,769, 170-171
(Garrettoconcha) maupiensis 56, 72,
111, 122, 126, 151, 153, 154, 163-
165, 166-168, 769, 315, 446, 461,
463
(Garrettoconcha) parvidens 8, 65,
67, 122, 153, 154, 163-165, 168,
171,772, 173,174,386,387
( Garrettoconcha ) punctiperforata
53, 54, 65, 117, 122, 151, 153,
154, 163, 165, 168-170, 769, 387,
491
(Garrettoconcha) rarotongensis 65,
67, 117, 122, 151, 153, 154, 163,
165, 171,772, 173-174
(Garrettoconcha) saintjohni 50, 122,
153, 154, 163-165, 166, 767. 168,
315,386,387
(Garrettoconcha) subtilis 58, 72, 122,
153, 154, 163-165, 171-173, 7 72
(Garrettoconcha) unilamellata 62,
122, 151, 154, 161-165, 174, 775,
177,178
(Af.) zebrina 117, 122, 151, 153-155,
757, 159, 161-162, 164
(Af. ) zimmermani 37, 82, 83, 87, 117,
122, 127, 736, 151, 153-156, 159-
161,760, 162,154,224,226
megacephala, Pheidole 100
megomphala megomphala, Opanara
249-250
Opanara 249-251
tepiahuensis, Opanara 250-251
Mesurethra 103, 105
Mexcyclotus 14
micro, Minidonta 132-134
micraconica, Minidonta 135-137
micrasoma, Libera 391-393
Microcystinae 92, 97, 105, 107
Microcystis ornatella 273
microtorma, Opanara areaensis 245-
246
microundulata, Ptychodon 37
Minidonta 17, 39, 48, 54, 57, 58, 61-63,
67-69, 71-73, 79-81, 83, 85, 96, 109-
113, 116-122, 125, 126-151, 178,
179, 189, 191, 196, 212, 213, 227,
255, 256, 289, 344, 349, 488, 489,
493
anatonuana 111, 112, 117, 122, 126-
130, 134, 139, 740, 140-141, 747,
742. 145, 290, 489
extraria 57, 117, 122, 126-130, 749.
150-151,180, 185
gravacosta 56, 117, 122, 126, 127,
129, 130, 137-139, 138, 145, 210,
212
haplaenopla 117, 122, 126-128, 129,
130, 134, 740, 747, 143-146, 744,
145, 146, 290
hendersoni 26, 34, 35, 72, 82, 83, 87,
111, 117, 118, 122, 126-130, 132,
733, 133, 134-135, 736, 145, 212,
255, 256
inexpectans 69, 111, 116, 117, 122,
125-130, 737, 132, 140-143, 146,
468, 488
manuaensis 111, 116, 117, 122, 126-
129, 130-132, 737, 132, 141, 143,
145, 146
micro 72, 111, 117, 118, 122, 126-130,
132-134, 733, 134, 135, 145, 180,
185,212
micraconica 56, 68, 72, 111, 117, 122,
127, 129, 130, 135-137, 738, 145,
210,314,489
planulata 72, 117, 122, 126-130, 740,
747, 744, 145, 146, 290, 296, 314
rotellina 57, 111, 117, 122, 125, 126-
130,737, 139, 145, 168,489
simulata 53, 111, 117, 122, 127-130,
145, 747, 148, 150, 178, 180, 185,
196,341,344,400,434,489
sulcata 117, 122, 126-130, 140, 141-
143,742, 145,314
taravensis 57, 58, 59, 117, 122, 126-
130, 145, 148-150, 749, 151, 179,
180, 185
taunensis 117, 122, 127-130, 134,
145, 146-148, 747, 150, 151, 180,
185
minutissima. Helenoconcha 151
mirabilis, Gambiodonta 440-441
montana, Orangia cookei 285-286
multilamellata, Thaumatodon 448-451
Mystivagor mastersi 93
Nesodiscus 17, 25, 26, 33, 47, 48, 51,
53. 54, 56-62, 67-69, 71-75, 80, 81,
83,85,87,94,98, 110-114,116, 119,
121, 124, 126, 151, 153, 156, 210,
314, 345-365, 368, 371, 383, 388,
389, 444, 466, 489, 493
var. acetabulum 46, 343, 346, 348,
349, 355, 357, 358
var. celsus 343, '346, 348, 349, 357,
358
cretaceus 46, 50, 124, 343, 345, 346,
348, 349, 351, 358-360, 359, 362,
363, 466, 468
fabrefactus 29, 46, 50, 62, 119, 124,
314, 343, 345, 347-349, 351, 360,
367. 362,363-364,466
fabrefactus var. piceus 46, 124, 343,
345, 347-349, 351, 359, 360, 363,
364
ftctus 10, 46, 50, 82, 87, 96, 124, 343,
345, 347-349, 350, 351, 358, 360-
363,367, 363,364
huaheinensis 8, 46, 50, 56, 124, 156,
343, 345, 346, 348, 349, 351, 352,
353, 354, 357, 358, 368
magnificus 29, 30, 46, 50, 62, 124,
343, 345, 349, 351, 363, 364-365,
365, 443
obolus 50, 56, 124, 336, 342-345, 348,
351, 352, 354-358, 356, 363, 384
obolus var. obolus 46, 343, 346, 348,
349, 355, 357, 358
taneae 19, 31, 34, 37, 47, 46, 50, 53,
56, 124, 156, 343, 345, 346, 348,
349, 351-354, 353, 357, 358, 365,
368
Nesophila 3, 39, 53, 54, 57-59, 61-63,
68, 69, 71, 73-75, 80, 81, 83, 85, 110-
113, 118, 119, 121, 124, 125, 207,
210, 224, 249, 332, 365-368, 371,
376, 444, 489
baldwini 124, 367
capillata 37, 50, 74, 124, 367-368
distans 124, 367
tiara 29, 30, 46, 50, 74, 80, 83, 87, 92-
95, 124, 222, 365, 366-367, 374
normalis, Ruatara oparica 273-275
nudus, Cookeconcha 214
obesa, Anceyodonta 201-204
obolus var. obolus, Nesodiscus 354-358
octolamellata, Taipidon 324
opanica. Helix 271
Opanara 15, 16, 17, 26, 54, 56, 58, 61-
63, 67-69, 71, 73, 76, 80, 81, 83-86,
92, 94, 96, 110-112, 115, 116, 120,
121, 123, 126, 227-255, 255, 272,
289, 336, 368, 370, 389, 489, 490-
492
altiapica 17, 51, 76, 80, 82, 95, 115,
123, 223, 227,229, 230, 231, 232,
236, 237, 246, 247, 248-249, 251,
491,492
areaensis 16, 17, 19, 42, 43, 44, 53,
58, 63, 65, 76, 81, 82, 115, 227,
230, 231, 233, 239-246, 273, 275,
287, 393, 491, 492
areaensis areaensis 43, 54, 55, 63, 65,
123, 223, 227, 228, 231-233, 237,
240, 241-244,243, 256, 289
areaensis densa 87, 115, 123, 223,
227, 231-233, 237, 240-242, 243,
244-245,246,491
areaensis microtorma 73, 76, 123,
223, 227, 231-233, 235, 237, 240-
242,243. 245-246,491
bitridentata 65, 67, 76, 78, 80, 82, 83,
115, 123, 223, 227,228, 230, 231-
233, 234, 235-238, 236, 237, 254,
286, 368
caliculata 17, 80, 115, 123, 223, 227,
230, 231, 232, 235-237, 246-247,
247, 251,491,492
depasoapicata 80, 83, 115, 123, 223,
227, 228, 230, 231, 232, 233-235,
236, 237, 239,252, 336, 490
duplicidentata 52, 56, 76, 77, 82, 115,
123, 223, 227, 228, 230, 231-233,
234, 235-237, 238-239, 238, 259,
368
fosbergi 39, 53, 58, 80, 92, 115, 123,
223, 227, 229, 230-233, 236, 237,
239,251-253,252,254
megomphala 16, 17, 54, 57, 62, 76,
78, 80,82, 111, 115,227,230-233,
241, 249-251, 273, 332, 366, 471,
492
megomphala megomphala 17, 53,
113, 116, 123, 223, 229, 232, 236,
237, 248, 249-250,250, 251, 287
506
SOLEM: ENDODONTOID LAND SNAILS
megomphala tepiahuensis 17, 76, 80,
113, 123, 223,229, 232, 236, 237,
248,249,250-251,250,253
perahuensis 80, 115, 123, 126, 223,
227, 229, 230-232, 236, 237, 252,
253-255, 267, 490, 491
opanica, Helix 271
oparica, Helix 271
oparica normalis, Ruatara 273-275
oparica, Ruatara 271-273
Ruatara 265-276
reductidenta, Ruatara 275-276
Opisthobranchia 102
Opisthostoma retrovertens 31
Orangia 61, 67-69, 71, 73, 76, 80, 81, 83,
85, 92, 95, 96, 110-112, 115, 116,
120, 121, 123, 126, 230, 232, 239,
255, 272, 276-289, 290, 336, 368-
370,490,491
cookei 17, 57, 58, 81, 82, 96, 115, 123,
241, 273, 276, 277, 279-287, 288,
289, 393, 491, 492
cookei cookei 42, 52, 123, 257, 276,
277, 278, 279, 280, 281, 281-
285,282
cookei montana 52, 54, 123, 239, 257,
276-278, 279, 280, 287, 282, 283,
284, 285-286
cookei tautautuensis 73, 123, 126,
257, 276, 278, 279, 287, 282, 283-
285, 286-287
maituatensis 39, 82, 115, 123, 257,
276-278, 279, 280, 282, 283, 284,
287-288, 491
sporadica 39, 61, 67, 80, 82, 115, 123,
257, 276-278, 279, 280, 282, 283,
284, 287, 288-289, 491
orbis, Hiona 273
ordinaria, Philonesia 337
ornatella, Microcystis 273
orofenensis, Libera bursatella 397-398
Orpiella 105
Ostodes 14
otareae, "Patula" decorticata form 162
othnius, Kondoconcha 368-371
Otoconcha 104
dimidiata 106
Otoconchinae 105-107
Oxychilus 75
pagodiformis, Pitys 118
Paralaomidae 105
Pararhytida 118
Partula 389
Partulidae (partulid) 104
parvidens, Mautodontha (Garretto-
concha) 171
Paryphantidae (paryphantid) 30
Patula 105, 118
decorticata form otareae 162
janeae 351
Patula (Endodonta) perarmata 199
paucicostatus, Cookeconcha 218-219
paucilamellatus, Cookeconcha 219
pelewana, Aaadonta 482-483
perahuensis, Opanara 253-255
perarmata, Patula (Endodonta) 199
petricola decora, Taipidon 322-324
petricola, Taipidon 318-322
pharcata, Australdonta 311-312
Phasis 118
Pheidole megacephala 100
Philonesia ordinaria 337
piceus, Nesodiscus fabrefactus var.
364
pilsbryi aukenensis, Gambiodonta
436-438
pilsbryi, Gambiodonta 436
Pitys 118
filicostata 218
pagodiformis 273
Planilaoma luckmanii 85
Planudonta 48, 53, 54, 56-62, 68, 69, 71,
73, 76, 79-83, 86, 87, 93, 95, 99,
110-113, 116, 119, 121, 123, 125,
227, 289, 315, 317, 330, 335-342,
489
concava 15, 47, 49, 50, 51, 62, 76, 80,
82, 83, 92-94, 123, 335, 336, 337,
338, 339, 340-342, 341, 342, 343
intermedia 15, 53, 54, 57, 76, 78, 80,
82, 123, 249, 331, 332, 335-337,
338, 339-340, 341, 342, 343, 366
matauuna 57, 123, 335-337, 339, 341,
342, 343
subplanula 80, 92, 94, 123, 335, 336,
337-339, 338, 339, 340, 341, 343
planulata, Minidonta 146
Planorbidae 102
Pleurodiscidae (pleurodiscid) 30
Poecilozonites 19
Polygyridae (polygyrid) 30, 53
Polyplacognatha 106
Pomatiasidae(pomatiasids) 14,95
Priceconcha 36, 44, 54, 56, 65-69, 71,
73, 79-81, 83, 86, 92, 96, 101,
110-113, 120, 121, 124, 255, 444,
448, 465-466, 468, 470, 489
tuvuthaensis 1, 19, 49, 54, 73, 79, 80,
90, 93, 100, 124, 125, 349, 390,
465-466, 468, 470
propinqua, Thalassohelix 74, 93
Prosobranchia 102
Pseudocharopa lidgbirdi 93
Pseudocharopidae 105, 107
Pseudolibera 27, 28, 39, 57, 58, 60-62,
68, 69, 71, 73, 76, 110-113, 119, 121,
124, 224, 381, 383-385, 386, 431,
468, 489
lillianae 47, 49, 124, 126, 383, 384-
385, 384, 443
pseudplanulata, Australdonta 294-296
Ptychodon 118,119,127
davidillQ, 118
eniwetokensis 116
microundulata 37
Pulmonata 102
Punctidae (punctid) 1, 2, 9, 10, 93, 94,
105, 106, 126
punctiperforata, Mautodontha (Gar-
rettoconcha) 168-170
Punctinae 105
Punctum 3, 50, 106, 118, 125
Pupillidael,53, 104
pupillids 50
Pyramidula 118
Pyramidulidae (pyramidulid) 30
radiella, Australdonta radiella 306-307
radiella, Australdonta 306-307
rurutuensis, Australdonta 307
Radioconus 106
Radiodiscus 106
raivavaeana, Australdonta 307-310
rarotongensis, Libera fratercula 425-
426
Mautodontha (Garrettoconcha) 173-
174
recedens, Libera 403-405
reductidenta, Ruatara oparica 275-276
Retinella 50
retrovertens, Opisthostoma 31
retunsa, Libera 412-413
Rhysoconcha 31, 56-58, 61, 62, 67-69,
71, 73-76, 79-83, 92, 96, 100, 109-
112, 115, 116, 120, 121, 123, 126,
136, 230-232, 241, 255-265, 315,
393, 470, 490, 491
atanuiensis 30, 31, 34, 42, 65, 67, 79,
115, 123, 255-260, 261, 262-264,
263, 265, 289, 492
variumbilicata 42, 57, 67, 79, 115,
123, 736, 189, 255, 256, 257,
258-262,263, 264, 265, 492
Rikitea 57-59, 61, 62, 68, 69, 71, 73,
110-114, 121, 123, 125, 342-345,
489
insolens 50, 73, 123, 342, 343, 344-
345,344
rimatarana, Australdonta 296-298
ringens, Cookeconcha 215-216
Rotadiscinae 105, 106
Rotadiscus 106
rotellina, Minidonta 139
rotundatus, Discus 199
Ruatara 58, 61, 67-69, 71, 73, 80, 83, 86,
92, 95, 110-112, 120, 121, 123, 126,
136, 230-232, 254, 255, 265-276,
490,491
koarana 53, 58, 123, 232, 236, 242,
257,265,266,266-267,272
oparica 16, 17, 53, 60, 65, 79, 81
82, 241, 254, 257, 266, 267-
276,270, 271, 289, 393, 492
oparica normalis 16, 67, 75, 78, 123,
736, 257, 265, 267, 268, 269, 271,
272, 273-275, 276, 490
oparica oparica 65, 67, 123, 257, 265,
267, 269, 271-273, 274, 275, 490,
491
oparica reductidenta 16, 60, 62, 65,
75, 90, 123, 736, 257, 265, 267,
268, 269, 272, 274, 275-276, 491
rubiginosa, Helix 220, 222
rugata, Endodonta 377
Rumina decollata 95
rurutuensis, Australdonta radiella 306-
307
Ryssota 105
saintjohni, Mautodontha (Garretto-
concha) 166
sculptilis, Libera 419
semimarsupialis, Taipidon 330-331
Serpho kiwi 93
Sesarinae 104
setigera, Helix 220
sexlamellata, Anceyodonta 196-199
Sigmurethra 85, 103, 104, 105
simulata, Minidonta 150
Sonorella 375
soror, Anceyodonta 195-196
spirrhymatum, Thaumatodon 465
sporadica, Orangia 288-289
spuria, Libera 407-410
INDEX
507
stellulus, Cookeconcha 217-218
Stenopylinae 105, 106
Stephanoda 118
stipulata, Aeschrodomus 74
streptaxon, Libera 413-415
Strep toneura 102
Striatura 50
Strobilopsidae (strobilopsid) 30, 53
Strobilus 273
Strophocheilidae 103
Stylommatophora 102
subcavernula, Libera 426-428
subconica, Anceyodonta 188-189
subdaedalea, Thaumatodon 461-463
subpacificus, Cookeconcha 211-212
subplanula, Planudonta 337-339
subtilis, Mautodontha (Garrettocon-
cha) 171-173
Subulinidae (subulinid) 95
Succinea 75
succinea, Electrina 273
sulcata, Minidonta 142
Systellommatophora 102
Taipidon 15, 16, 26, 39, 48, 54, 56, 58-
61, 67-69, 71-73, 76, 79, 80-83, 86,
92, 93, 95, 99, 104, 110-113, 115,
116, 119-121, 123, 125, 227, 289,
314-335, 336, 344, 489
analogica 57, 115, 123, 315-319, 324,
326, 327, 328-330, 329, 331, 332
anceyana 115, 123, 314-319, 327-328,
327
centadentata 15, 53, 54, 57, 62, 76,
80, 82, 90, 92-95, 115, 116, 123,
249, 314-319, 321, 328, 331-333,
332, 334, 335, 339, 366
fragila 15, 16, 65, 76, 79, 80, 82, 92,
94, 96, 115, 123, 314, 316-318,
320, 332, 333, 334, 334-335, 336
marquesana 65, 115, 123, 314-319,
324,326,327, 328
octolamellata 115, 123, 314-318,
324,325, 327
petricola decora 56, 65, 72, 76, 78, 79,
84, 85, 86, 89, 90, 123, 316-319,
320, 322, 322-324
petricola petricola 62, 76, 77, 80, 82,
115, 123, 314-317, 318-322, 320,
322, 327, 328, 337
semimarsupialis 15, 28, 57, 60, 76,
79, 80, 82, 86, 87, 92-94, 111, 113,
115, 116, 119, 120, 123, 314-317,
319, 321, 328, 329, 330-331, 332,
335, 386, 458, 468
varidentata 15, 16, 65, 76, 79, 80, 82,
83, 92, 94, 95, 115, 123, 314, 316,
317-319, 320, 332. 333-334, 334,
335, 336
woapoensis 65, 67, 115, 123, 314-319,
324-326, 325, 326, 327, 328, 337
taneae. Nesodiscus 351-354
tapina. Australdonta 302-304
taravensis, Minidonta 148-150
taunensis, Minidonta 146-148
tautautuensis, Orangia cookei 286-287
Tekoulina 76
tepiahuensis, Opanara megomphala
250-251
thaanumi, Cookeconcha 219-220
Thalassia 118
Thalassohelix propinqua 74, 93
Thaumatodon 26, 39, 49, 54, 56, 57, 59,
61, 63, 65, 67-69, 71, 73, 76, 79-81,
83, 85, 92-94, 99, 101, 110-112, 114,
116, 118-121, 124-126, 128, 162,
213, 255, 289, 444-465, 466-468,
470, 489, 490
corrugata 37, 39, 47, 114, 124, 444-
448, 454, 460, 461, 463-464, 465,
468, 489
decemplicata 31, 79, 114, 124, 125,
444-448, 449, 450, 451-453, 452,
454,461,489
euaensis 28, 39, 47, 57, 65, 75-77, 79,
84, 86, 95, 113, 114, 124, 386,
444-448, 453, 454, 456-458, 457,
458, 459, 461, 463, 470, 489
hystricelloides 12, 39, 57, 63, 64, 65,
75, 78, 79, 87, 90, 91, 93-95, 100,
114, 120, 124, 126, 444-448, 449,
453-456, 457, 458, 461, 462, 470,
486, 489
laddi 114, 124, 444-448, 452, 453,
454,464-465,468,489
multilamellata 56, 57, 65, 67, 114,
124, 125, 428, 444-447, 448-451,
450,453,454,489
spirrhymatum 1, 19, 44, 64, 65, 73,
79, 87, 90, 93, 95, 124, 218, 444,
446-448, 465, 489
subdaedalea 47, 114, 124, 444-448,
451, 454, 461-463, 462, 464, 465,
467, 468, 489
vavauensis 39, 57, 114, 124, 444-448,
453, 455, 456, 458-461, 460, 463,
489
thwingi, Cookeconcha 213-214
Thysanotinae 105
tiara, Nesophila 366-367
Tornatellinidae 5, 10, 53, 76, 100, 118,
488
Tracheopulmonata 103
trochlearis, Antonella 273
Trochomorpha 118
Trochomorphidae (trochomorphid) 92,
95, 104, 105
Trochomorphinae 97
Tubuaia hendersoni 135
tubuaiana, Australdonta 311-312
tumida, Gambiodonta 441
tumuloides, Libera 428-430
tuvuthaensis, Priceconcha 465-466
umbilicata, Libera 410-412
unilamellata, Mautodontha (Garretto-
concha) 178
Urocoptidae 95
Urpulmonata 103
Vallonia 50
varidentata, Taipidon 333-334
variumbilicata, Rhysoconcha 258-262
vavauensis, Thaumatodon 458-461
vicaria, Charopa 74
woapoensis, Taipidon 324-326
yoshii, Australdonta 304
zebrina, Mautodontha (M. } 161-162
zimmermani, Mautodontha (M. ) 159-
161
Zonitidae (Zonitoids) 1, 19, 30, 100,
107
Zonitoides 50
Zyzzyxdonta 54, 56, 57, 61, 65, 68, 69,
71, 73, 80, 110-112, 114, 116, 120,
121, 124, 289, 444, 447, 448, 465,
466-467, 468, 489
alata 114, 124, 125, 445, 447, 454,
466-467, 466, 468
Agakauitai Islet 150, 184, 189, 198,
203, 204, 206, 207, 432, 435, 443,
444
Aitutaki 57, 116, 122, 124, 127, 128,
139, 151, 153, 154, 165, 168-171,
390,419,423,489
Akamaru Islet 184, 198, 203, 204, 206,
207, 432, 434
Ambon 118
Anaa 122, 153, 158
Angaur 124, 472, 477, 484, 486, 487
Aru Islands 118
Atiu 122, 124, 151, 153, 154, 165, 173,
174,419,423,424
Geographic Index
Aukena Islet 134, 150, 151, 179, 184,
186, 187, 189, 191, 198, 200, 201,
203, 204, 206, 207, 432, 434, 437,
438,440-444,467
Auluptagel472
Australia 6, 8, 10, 30, 37, 73, 76, 83, 92,
100, 106, 107, 112, 118,489,490
Austral Islands 7, 33, 56, 101, 113,
117, 122-125, 127, 128, 137, 139,
141, 143, 145, 146, 151, 154, 159,
227-314,488,489
Austrozelandic region 75, 104, 488
Babelthuap 124, 472-474, 477, 478
BiakllS
Bikini Atoll 2, 116, 118, 122, 123, 127,
128, 130, 132, 211, 212, 465, 468,
488, 489
Bismark Archipelago 118, 448
Borabora 41, 122, 124, 153, 154, 156,
166, 345, 351, 352, 354, 358, 360,
365, 386
Caroline Islands 2, 7, 125, 467, 488, 489
Cook Islands 7, 9, 28, 49, 50, 57, 88,
100, 101, 112, 121-125, 128, 139,
153, 154, 161, 162, 168-175, 178-
292, 298, 300, 305, 390, 418-430,
446,448,450,451,488,489
508
SOLEM: ENDODONTOID LAND SNAILS
Dominique ( see Hivaoa )
Eiao 84, 89, 123, 315, 318, 320, 322, 323
Ellice Islands 7, 9, 116, 124, 125, 446,
448, 449, 451, 452, 468, 488, 489
Eniwetok Atoll 2,118, 465, 488
Eua 28, 124, 446, 448, 457, 458, 459
Fatuhiva315
Fatuuku315
Fiji Islands 1, 2, 5, 6, 7, 9, 10, 110, 116,
118, 124, 125, 166, 168, 349, 452,
461,462,464,468,488
Funafuti Atoll 2, 1 18, 465
Gambler Islands 32, 56, 57, 112, 122-
125, 128, 134, 148, 150, 151, 178-
207, 432-444, 488
Gondwanaland 104, 488, 489
Guam 7, 9
Ha'apai group 446
Hatutu 123, 315, 318, 320, 322, 323
Hawaii 1, 2, 3, 6, 7, 8, 10, 28, 36, 40, 48,
50, 53, 56, 62, 63, 65, 67, 81, 90, 99-
101, 110, 112, 114, 116, 118, 119,
122-125, 137, 211, 213-217, 220-
222, 249, 314, 315, 332, 365-368,
370-383, 444, 465, 467, 488, 493
Henderson 5, 35, 118, 122, 125, 127,
128,134,135,489
Hivaoa 15, 82, 123, 315, 317, 320, 324,
325, 327, 328, 333, 335, 337, 341,
342
Huahine 122, 124, 153, 154, 165, 171-
173,344,354,356,358,386
Indonesia 9, 107, 112,489,490
Juan Fernandez 1 18, 488
Kauai 48, 100, 123, 124, 211, 216, 221,
222, 365-368, 369, 375, 377, 379
Kermadec Islands 107, 488
Kimbombo 124, 446, 463
Koror 124, 472-474, 477-481, 483
Lanai 123, 124, 215, 216, 221, 378, 379
Lau Archipelago 1, 6, 9, 10, 19, 36, 100,
116, 124, 125, 390, 444, 446, 448,
452, 462-468, 488, 489
Laurasia 104
Lord Howe 4, 6, 10, 73, 92, 93, 106, 107,
488, 489
Makatea 28, 48, 113, 121-124, 153, 157,
158, 224-226, 384, 385
Mangaia 124, 419, 423, 424
Mangareva 5, 7, 8, 10, 20, 22, 28, 32,
39, 57, 62, 67, 73, 101, 110, 112,
114, 116-118, 120-125, 127, 128,
130, 134, 148, 150, 151, 179, 184-
194, 196-207, 210, 305, 344, 345,
365, 432, 434-438, 440-444, 489
Mangier (see Mangaia)
Mango 124, 446, 461-464
Manua 122, 128, 130, 489
Mariana Islands 1, 125, 488, 489
Marquesas Islands 1, 5, 7, 15, 28, 76,
79,80-83,89,99, 101, 108, 110, 112,
114, 116, 119, 122, 123, 125, 128,
227, 249, 314-343, 366, 414, 417,
458, 488, 489, 493
Marshall Islands 116, 118, 122, 123,
125,132,211,212,488
Maui 36, 40, 123, 124, 216, 220, 221,
377
Mauke 123, 124, 292, 298-300, 419,
423, 424
Maupiti 122, 124, 153, 166, 168, 169,
351-354
Melanesia 9, 74,85
Micronesia 1, 2, 5, 9, 74, 79, 83, 85, 121,
444, 468, 488, 489
Midway Atoll 1 16, 1 18, 488
Misool 118
Mohotani315
Molokai 123, 124, 215, 216, 220, 221,
377-379
Moorea 4, 28, 122, 124, 153, 168-171,
386, 389, 390, 393, 394, 398, 402-
408,413,414,418,430
Navutu-I-Loma 124, 466, 467
Neotropical 107
New Caledonia 4, 6, 10, 73, 81, 92, 94,
100, 106, 107, 488, 489
New Guinea 112, 448, 489, 490
New Hebrides 2, 6, 10, 488
New South Wales 107
New Zealand 4, 6, 8, 10, 30, 37, 39, 73,
74, 81, 83, 85, 92-94, 100, 104-107,
118, 127,489
Ngemelis 124, 472, 473, 478
Niau 122, 153, 158
Niue9, 116
Norfolk 4, 6, 10,107,488
Nukufetau 124, 446, 451-453, 489
Nukuhiva 15, 28, 82, 123, 314, 317,
318, 321, 324, 326, 327, 329, 331,
332,335,337-341
Oahu 28, 57, 90, 100, 123, 124, 210, 211,
213, 215, 216, 220, 367, 368, 372-
375, 376, 378-382
Olosega 122, 130
Opana (see Rapa)
Opara ( see Rapa )
Palau Islands 1, 20, 23, 38, 39, 107,
110, 116, 122, 124, 125, 444, 468-
489
Papua 107
Peleliu 38, 39, 124, 472-475, 479, 480,
481-483
Philippine Islands 7, 108
Polynesia 1, 2, 5, 9, 31, 74, 118, 444,
488-490
Raiatea 122, 124, 154, 174-176, 178,
344, 351, 355, 356, 358-364
Raivavae 33, 113, 122, 123, 128, 137,
139, 141, 143, 146, 158, 159, 210,
292,309,313,314,489
Rapa 5, 10, 15, 16, 17, 20, 22, 28, 39,
49, 54, 57, 60, 62, 80, 82, 92, 100,
101, 110, 112, 113, 116, 118, 120,
121, 123-126, 128, 151, 189, 227-
289, 315, 332, 366, 368, 369-371,
376, 393, 488, 489-492, 493
Rarotonga 6, 7, 8, 10, 12, 49, 87, 88,
122, 124, 151, 153, 154, 162, 165,
175, 178, 386, 390, 399, 417-419,
423-428, 430, 446, 448, 450, 451,
468, 489
Rimatara 123, 292, 298, 299, 300
Rotuma 9
Rurutu 7, 122, 123, 128, 143, 145, 292,
298-300, 303-305, 307, 332, 366,
489
St. Helena 63, 107, 118, 151, 489
Samoa 6, 7, 9, 12, 91, 101, 116, 118,
122, 124-128, 130, 132, 319, 446,
448-450, 453, 454, 456, 458, 462,
468, 488, 489
Sandwich Islands (see Hawaii)
Savaii 10
Society Islands 1, 5, 7, 8, 28, 41, 50,
100, 110, 112, 116, 117, 119, 121,
122, 124-126, 128, 151, 153, 154,
156, 161, 162, 165, 166, 168-175,
178, 344-365, 371, 385-418, 488,
489
South Africa 4, 107, 489
South America 4, 107, 1 18, 489
Tahaa 124, 344, 349, 351, 360-363
Tahiti 1, 4, 6, 8, 10, 15, 28, 37, 41, 81,
82, 100, 122, 124, 153, 154, 156,
157, 161, 162, 165, 171, 172, 174,
176, 344, 354, 355, 386, 389, 390,
391, 394, 396, 398-401, 403, 405,
407, 408, 411-414, 416-418, 430,
465
Tahuata315
Taravai Islet 151, 184, 198, 199, 206,
207
Tasmania 85
Tau 122, 130
Thithial, 124,446,465
Timor 118
Tonga Islands 6, 7, 9, 10, 28, 74, 116,
124-126, 446, 448, 450, 454, 456-
459,461,463,468,488
Truk 467
Tuamotu Islands 5, 28, 73, 112, 122-
126, 128, 151, 154, 156, 158, 224-
226, 384, 385, 488, 489
Tubuai 123, 292, 305-307, 311-313, 332,
366
Tuvutha 1, 124, 465, 466
Uahuku315
Uapou 123, 318, 324-326
Upolu 10, 91, 100, 101, 124, 446, 449,
453, 455, 462, 489
Vaitupu 116, 124, 446, 449, 451, 453,
489
Vanua Mbalavu 124, 446, 462
Vavau 124, 446, 448, 454, 458, 461, 489
Viti Levu 6, 10, 100
Wangava 124, 446, 452, 453, 464
Western Australia 107
West Irian 118
Yangasa Cluster 124, 466, 467
>
Live Music Archive
Librivox Free Audio
Metropolitan Museum
Cleveland Museum of Art
Internet Arcade
Console Living Room
Books to Borrow
Open Library
TV News
Understanding 9/11