Z - Nf^ - Yfo^-y HARVARD UNIVERSITY % Library of the Museum of Comparative Zoology sS - /V/)- f[A^^oJ BRIGHAM YOUNG UNIVERSITY \i^ SCIENCE BULLETIN ^US. COMP. 200L LIBRARY MAY 2 0 1965 UNIVERSITY TENEBRIONIDAE BEETLES OF THE NEVADA TEST SITE by Vasco M. Tanner and Willis A. Packham Biological Series — Vol. VI, No. 1 FEBRUARY, 1965 BRIGHAM YOUNG UNIVERSITY SCIENCE BULLETIN TENEBRIONIDAE BEETLES OF THE NEVADA TEST SITE by Vasco M. Tanner and Willis A. Packham Biological Series — Vol. VI, No. 1 FEBRUARY 1965 FOREWORD Tliis is anotluT of a series of major publications on desert ecology resulting from studies at the Nevada Test Site by the Brigham Young Universit)' Depart- ment of Zoology and Entomology in cooperation with the United States Atomic Energy Commission. Although some of the studies are the result of indepen- dent investigations by specialists who are not on our departmental staff, they are j)art of the major project initiated cooperatively by B.Y.U. and the AEC to dclermine the effect of nuclear detonations on the native animals of the Nevada Test Site. Dorald M. Allred and D Elden Beck Project Supervisors MUS. COMP - ■^'- HAH- TABLE OF CONTENTS Page INTRODUCTION 1 ACKNOWLEDGMENT 2 ACCOUNTS OF THE SPECIES 2 CLASSIFICATION OF THE TENEBRIONIDAE COLLECTED AT THE NEVADA TEST SITE 3 KEY TO THE SUBFAMILIES 4 CHARACTERISTICS OF THE TRIBES, GENERA, AND SPECIES 7 SYSTEMATIC AND ECOLOGICAL DISCUSSION OF THE SPECIES OF TENE- BRIONIDAE COLLECTED AT THE NEVADA TEST SITE 16 Metoponium convexicolle 16 Hylocrinus laborans 17 Steriphanus lubricans 17 Auchmobius subboreus 17 Chihmetopon abnorme 18 Metopoloba bifossiceps 18 Triorophus laevis politus 19 Edrotes orbus 19 Araeoschizus sulcicoUis 20 Anepsius brunneus 21 Cryptoglossa verrucosa 23 Centrioptera muricata 23 Pelecyphorus pantex 24 P. semilaevis 25 Euschides luctatus 26 Trichiasida acerba 26 Craniotus bUiisdelU 27 Trogloderus costatus nevadus 29 Embaphion elongatum 29 Eleodes carbonaria immunis 29 E. obscura sulcipennis 30 E. grandicoltis valida 31 E. hispilabris sculptilis 32 E. longipilosa 32 £. armata 33 E. armata pumila 33 E. nigrina 34 E. dissimilis nevadensis 34 E. longicoUis 34 E. tenebrosa 34 £. brunnipes brevisetosa 33 E. extricata jrigida 35 Spheriontis dilatata 35 Eusattus dubius 36 E. agnatus 36 Coniontis nevadensis carsonica 36 Conkmtellus argutus 37 Blapstinus vandyhei 37 B. pubescens 37 Notibius substriatus 37 Conibiosoma elongatum 38 Anemia calif ornica 38 Coclociwmis punctatu 39 Alucphus nevadensis 39 Eupsophulus costaneus 40 Ih'lops attenuatus 40 DISCUSSION 41 AbumlancL' of Species 41 Populations 41 Plant Communit)' Relationships 42 Seasonal Activit)' 42 Life HLstory and Food Habits 42 SUMMARY 43 LITERATURE CITED 43 LIST OF FIGURES Figure Page I. Eleodes grandicollis validti Boheman, dorsal view 5 II. Eleodes grandicollis valida Boheman, ventral view 6 III. Auchmohiiis siihboreus Bhiisdell 18 IV, Numher of specimens by species (A-D) found in nine plant communities 19 V. Number of specimens by species (A-F) found in nine plant communities 20 V'l Numi)er of specimens by species (A-B) foimd in nine plant communities 21 \ll. Numl)cr of specimens by species (A-E) found in nine plant communities 22 \'II1 .Number of specimens by species (A-G) found in nine plant communities 22 I.\. Number of specimens by species (A-J) found in nine plant communities 23 X. Number of specimens seasonally in Mixed, Salsola, and Coleogyne communities .. 24 XI. Number of specimens seasonally in Larrea-Franseria, Lycium, and Atriplex- Kochia communities 24 XII. Number of specimens seasonally in Grayia-Lycium and disturbed Grayia- Lycium communities 24 .\III. Petecyplwrus pantex Casey 25 XIV. Petecyplwrus semilaevis ( Honi ) 25 .\\'. Number of specimens seasonally collected in all the biotic communities 26 .WI. Number of specimens seasonally collected in all the biotic communities 27 XV'II. Craniotus hlaisdelli Tanner 28 XVIII. Number of specimens seasonally collected in all the biotic communities 30 XIX. Number of specimens seasoniUly cxjUected in all the biotic communities 31 XX. Niunher of specimens seasonally collected in iUl the biotic communities 32 .\XI. Alaephus nevadensis Tarmer 39 TENEBRIONIDAE BEETLES OF THE NEVADA TEST SITE' by Vasco M. Tanner^ and Willis A. Packham^ INTRODUCTION In August 1959 Brigham Young University initiated an ecological study of the animals at the Nevada Test Site. As part of that study, emphasis was given to the ground-dwelling lu-thropods. One of the largest resulting collec- tions was beetles in the family Tenebrionidae. Tliese are herein described, and notes on dieir relative abundance, seasonal occurrence, and plant community relationships at the test site are included. Tlie results reported here deal with those collected between August 19.59 and July 1963. The Nevada Test Site is situated in southern Nye Countv adjacent to northwestern Clark- County and southwestern Lincoln County, about 70 miles northwest of Las Vegas, Nevada (refer to Allred, Beck, and Jorgensen, 1963a). It is appro.ximatelv 40 miles long and 35 miles wide. Beetles were taken from three major areas of the test site — Frenchman Flat, Yucca Flat, and Rainier Mesa. The geography and ecology of the area were discussed in detail by Allred, Beck, and Jorgensen (1963a) in Biotic Communities of the Nevada Test Site. Their plant community designations of Larrea-Franseria, Grayia-Ly- cium, Salsola, Coleogyne, Atriplcx-Kochia, Pin- yon-Juniper and Mi.xed have been followed in this paper with slight modification. In French- man Flat Li/ciiim pallidum occurs as a narrow, relatively pure stand which extends from the playa through the Larrea-Franseria. Inasmuch as the beetle fauna differed so much between this Lijcium area and other areas in the Larrea- Franseria community where Lycium was much less abundant, it is herein considered as a sep- arate community. In Yucca Flat the vegetation in large areas in the Grayia-Lycium community has been dis- turbed and partially destroyed by nuclear wea- pons testing. Here also the beetle fauna differed. These areas are referred to herein as disturbed Grayia-Lycium in contrast to the Grayia-Lycium ( undisturbed ) . Beetles were collected at regular intervals in sunken can traps described and illustrated by Allred, et al. (1963a). Others were collected intennittently by hand from plants, small mam- mal burrows, under rocks, debris, bark, etc., and by use of an ultraviolet light. Can traps usually were placed in two par- allel lines 825 feet apart, each line with six cans spaced at 1.50-foot intei-vals. In the Mixed com- munitv an additional line of ams spaced at ir- regular intervals was used, and in the Pinyon- Juniper the lines of cans were 75 feet apart. In the disturbed Grayia-Lycium, however, four lines of traps radiated from ground zero (the point where a nuclear detonation took place). Each of these lines extended through an area completely denuded of native plants (but now invaded by Salsola kali), through adjacent zones of physically damaged plants, and terminated in ;ireas of undisturbed vegetation. Each line con- sisted of thirty cans placed 265 feet apart. Regular collections were made in each com- munity for at least a year's period, except in the Pinyon-Juniper between November and March when snow cover prevented access to the study area. More incidental collections were made in some communities than in others. Therefore, for purposes of relative population comparisons, the total number of specimens collected in each community was adjusted according to the number of collection attempts. The tenebrionids were preserved in 70% ethyl alcohol until pinned. Identified specimens have been deposited in the collections of Brig- ham Young University and other institutions and museums as indicated by Allred, et al. (1963b). 'Report No. COO-1355-6. Fklci work completed under A EC Contract AT ( 11-1 ) 786. -Professor of Zoology and Entomology, Brigham Yoimg University, Provo, Utah. ^Instructor in Biological Sciences, Washington High School, Portland, Oregon. Bkiciiam Young University Science Bulletin ACKNOWLKDfAIKNT Acknowli-ilgment is made of United States Atomic KiuTj^- Commission contracts AT(ll-l)- 786 and Af( 11-1 ) 13.55 witli Brigliam Young Ijniversifv wliidi pro\'idod financial support for part of tliis study. We are grateful to Drs. Dor- aid M. Allred and D Elden Beck, principiil and ass(K-iate investigators of tlie Nevada Test Site ecology' projects, for permission to utilize their data and for their suggestions. Appreciation is expressed to Dr. Harold J. Grant, director of entomology. Academy of Natural Sciences of Philadelphia; Dr. T. J. Spilman, Department of Kntomology, U. S. National Museum, and Mr. Hugh B. Leech, curator of entomology, Calif- ornia .Academy of Sciences, for many c-ourtesies and loans of specimens to the senior author while at these respective institutions. We wish to thank .Mr. Douglas Hill of the Brigham Young University English Department, our artist, for the care he has taken in making the drawings contained in tiiis paper; and the personnel as- sociated with the Brigham Young Uni\ersity ecology project at the Nevada Test Site and Pro\o campus laboratory for the c-ollection and preparation of specimens. ACCOUNTS OF THE SPECIES The family Tenebrionidae in the United States is large and varied, with over 1,440 species and subspecies. The keys and literature to the family are scattered through many books and journals, and the ta.xonomic references to this family are voluminous. One of the e;irly work- ers wiis John L. LeConte, who described many species (1851, 1858). The great inorphologist, Lacordair, published a section on Tenebrionidae in his Histoire Naturelle dcs Insccta (1859). George H. Horn (1870) monographed the fam- ily and published additional treatises in 1874, 1878, and 1891. Thomas L. Casey was one of the prolific workers on this family. He revised the subfamilies Tentvriinae, Coniontinae, and the tribe Asidini (Casey 1907, 1908, 1912) and named man\' new genera and species. In 1909 Frank K. Blaisdell began a long series of publi- cations on the tribe Eleodiini. From his works came many of the subspecific names used in this study. As far as can be detennined, very little has been publisheti on the ecology of the beetles of the family Tenebrionidae, although the ta.xonomic papers of Horn (1870) and La- Rivers (1942, 1947, 1948) include notes on hab- itat and seasonal occurrence. In the four years this study was in progress at the Nevada Test Site, 14,6.50 specimens rep- resenting .31 genera and 46 sfX'cies and sub- species Were cxillected. These are presented in the following check-list arranged l)v subfamih', tribe and genus. Tlie number precetling the name indicates its rank in frecjuency of abun- dance at the test site. The numbers and letters following each name refer to the subfainil\ (1-1), tribe 1(1-1), genus 1(1-1)A and species 1(1-1).\-1. If the description of each category along with this code is followed, there should be very little difficulty in making a determina- tion of a species. Subfamily TENTYRIINAE ( 1-1 ) Tribe Eurymetopim 1(1-1) 9 Metoponium convexicolle LeConte 1(1-1)A-1 24 Hijlocrinus lahorans Casey l(l-l)B-2 33 Stcripluinus lubricaiis Casey l(l-l)C-3 Tribe Auchmobiim 2(1-1) 21 Auchmobius siihborcus Blaisdell 2(l-l)A-4 Tribe Trimytini 3( 1-1 ) 27 Chilometopan abnomie (Horn) 3(l-l)A-5 Tribe Epitr.agim 4(1-1) 29 Mctopololxi bifossiceps Casey 4(l-l)A-6 Trilx' TnioROPiiiN-i 5( 1-1 ) 6 TrioropJuis lacius poUtus Casey 5(l-l)A-7 Tribe Edrotim 6(1-1) 3 Edrotes orbtts Casey 6( 1-1 )A-8 Tribe .Ahaeoschizim 7(1-1) 2 Aracoscliizus sitlcicolU.s Horn 7(l-l)A-9 Tribe .\nepsiini 8(1-1) 22 .An<7).s7i/.v l>ntnnciis Casey 8(1-1)A-10 Tribe Cryptoclossi.m 9( 1-1 ) 16 Cn/ptotilosso vcrnicoso LeConte 9(1-1)A-11 5 Ccntrioplciv imiricalu LeConte 9(1-1)B-12 Biological Series, Vol. 6, No. 1, Febru.\ry, 1965 Subfamily ASIDINAE (1-2) Tribe Asidini 1(1-2) 11 Pelecyphorus pantex Casey 1(1-2)A-13 24 P. semilaevis (Horn) 1(1-2)A-14 19 Eitschides luctatm (Horn) 1(1-2)B-15 17 Trichiasida acerha (Horn) 1(1-2)C-16 Tribe Craniotixi 2(1-2) 35 Craniotus bhiisdeUi Tanner 2(1-2)A-17 Subfamily ELEODINAE (1-3) Tribe Eleodlxi 1(1-3) 14 Trogloderus costattis nevadits LaRivers 1(1-3)A-18 26 Embaphion dongatum Horn 1(1-3)B-19 10 Eleodes carbonaria immunis LeConte l(l-3)C-20 12 E. obscura sulcipcnnis Mannerheim 1(1-3)C-21 8 E. grancicoUis valida Boheman 1(1-2) C-22 4 E. hispihbrLs sculptilus Blaisdell l(l-3)C-23 31 E. longipilosa Horn 1(1-3) C-24 1 E. annata LeConte l(l-3)C-2.5 25 E. annata pumilu Blaisdell l(l-3)C-26 34 E. nigrina LeConte l(l-3)C-27 32 E. dlisimilis nevadensis Blaisdell l(l-3)C-28 31 E. longicoUis LeConte 1(1-3 )C-29 28 E. tenebrosa Horn 1(1-3) C-30 30 £. brutmipes brevisetosa Blaisdell 1(1-3)C-31 25 E. extricata frigida LaRivers l(l-3)C-32 Subfamily CONIONTINAE (1-4) Tribe Comoxtini 1(1-4) 34 Sphaeriontis dilatata (LeConte) l(l-4)A-33 20 Eusattus diibitis LeConte l(l-4)B-34 13 £. agnatus Casey l(l-4)B-35 24 Coniontis nevadeiisis carsonica Casey l(l-4)C-36 36 ConionteUus aigutus Casey l(l-4)D-37 Subfamily PEDININAE (1-5) Tribe Blapsti.ni 1(1-5) 23 Bhpstiinis vandijkei Blaisdell l(l-5)A-38 :M B. pubescens LeConte l(l-5)A-39 7 Notibius std)stikittis Casey l(l-5)B-40 18 Conibiosoma elongatum (Horn) 1(1-5)C-41 Subfamily OPATRINAE (1-6) Tribe Leichenini 1(1-6) 33 Anemia californica Horn l(l-6)A-42 Subfamily TENEBRIONINAE (1-7) Tribe Tenebrionini 1(1-7) 36 CoelocnemLs punctata LeConte l(l-7)A-43 33 Alacphus nevadensis Tanner, n. sp. l(l-7)B-44 24 Etipsophulus castaneus Horn l(l-7)C-45 Subfamily HELOPINAE (1-8) Tribe Helopini 1(1-8) 15 Helops attennatus LeConte l(l-8)A-46 CLASSIFICATION OF THE TENEBRIONIDAE COLLECTED AT THE NEVADA TEST SITE In this study the salient characteristics of the subfamilies, tribes, genera and species of the Tenebrionidae collected at the Nevada Test Site are presented in as simple a terminology as possible. It is hoped that these keys wiU be an aid to the student and layman in under- standing and learning about this large, inter- esting family of beetles. Some technical terms will of necessity be used, but with the aid of the accompanving drawings (Figs. I-II), we be- lieve that the descriptions and terminology may be understood. The family Tenebrionidae is the largest fam- ily of beetles in the superfamily or assemblage of widely diverse families known as the Cucu- joidea. The members of this family are com- monly known as "Darkling Beetles" and are prevalent in the western United States, where they have become well adjusted to the diy des- ert conditions. We are indebted to LeConte, Horn, Casey, Blaisdell, Bradley, Arnett and others for the use of their studies in the preparation of the follow- ing keys. VVe have selected, rearranged and added to the keys of these noted coleopterists. Rather than develop a short couplet key which is not easily used or understood by those not familiar with tenebrionid morphology, we have included rather lengthy chaiacterizations of the several categories used in this classification. The following suggestions are given to those who may use these keys. In order to determine BlIICIIAM \()INC L'MVKHbll V SciKNCt BULLETIN flit" spt'cics to uliicli a i;i\('n tciifhrioiiici hcctk' may bcloiig, A. First ilc'ti-iiniiic to \\ liitli oiu' of tlu- I'iglit siibfaiiiilies tlif spt-tiiiuii litloiigs. ( 1-1 ) to (1-8). B. Then, decide to wliicli tribe of that sub- fainilv tlie speeinien belongs. 1(1-1), etc. C. Once it is placed in the proper tribe, one will not iiave too much difficulty in as- signing it to the correct genus, e.g. 1(1-1)A. D. .\Ian\' of the genera are monotypic. One need onlv turn to the page of the te.xt and find the description of the species in (juestion, e.g. 1(1-1).\-1. If there are more tiian one species reported for a genus, a key to tiie different species will be found imder tiie genus heading. The drawings of a representative spec-ies ta- ken at tile test site have tiie main structures labeled. Reference to tiiese labeled drawings should help in uiKlerstaiKiiiig tiie terms used in the key;.. The F.vMiLY Tf.nebriomdae Tiie family Tenebrionidae may be recognized and separated from other Heteroinera Coieop- tera as follows: Front and middle tarsi five-jointed (Fig. I); tiie hind tarsi four-jointed (Fig. I); anterior coxal cavities closed behind (Fig. II); ventral abdominal segments four and five, in part connate (Fig. II); tarsal daws simple, the {>enultimate joint (Fig. I) of the tarsi not spongy beneatii. Species of eight sui:)families are represented in the collections made at tiie test site. Ki:V TO THE SUBFAMILIES (1-1) Subfamily Te.nytrunae Ventral segments of the abdomen entirely of a liornv substance; middle, or mesothoracic co.xae without trochantins; labrum or upper lip scarcely visible. Female genitalia quadrato- trianguiar in shape, vaivifer elongate, twice as long as wide; anal plate well developed, stylus rudimentary or entirely absent in some species. Male apicaie longer tiian the basaie; genital fossa large, widely open, apicaie sides of basaie infie.xed \entraliv in apical iiaif, connecting surface broadiv membranous, sides scieritized. (1-2) SubfaiiiiK .\smiNAE Epistoma, or lower (;ice between tiie mouth and eves ( F"ig. I ) truncated. \\ itli tlie margin cut into sinuses; ialirum well de\eloped, mau- diiiles thick, punctate, wide ajiicaliv, witii tip bifid; antennae with segments nine and ten wid- er tlian the eleventh wliicii is imijcdded in tiie concave apex of tiie eie\entli; meiitum large to iiKHlcr.ite in size, attaciied to a gnlar extension wiiicli ma\- in some genera fill the entire buc- cal opening; prothorax mucii wider than the head, and narrower than the elytra; legs rela- tively small, given to show movements. Genera and species subject to considerable variations. Female genitalia strongly scieritized, coxites and valvifers elongate, styli small; the terminal ab- dominal segments of the female are capable of being protruded to a remarkable length. Male aedeagus slender and elongate; apicaie is as long as the basaie and four times as wide (See figures I and II). (1-3) Subfamily Eleodln'.\e The principal characters of tiic abo\e sub- family are tiiese; mesocoxae iiave visible tro- chantins (Fig. II); the ventral abdominal seg- ments are entireiv corneous; eves not prominent, more or ie^s transverse, always emiu-ginate in front; next to the last joint of tarsi entire, not bilobed; hind joint of antennae usually longer tiian the following; hind coxae transverse, never obli(jue; tarsi spinose or setose beneatii; elytra widely embracing the body. The genitalia of the male is elongate flaxseed-shaped, apiaiie trian- gular with sides evenly arcuate, especially in the middle one-tiiird; dorsal surface with an oval, siigiitl\' impressed semi-memiiranous area. Val- vifers narrowlv iiiflexetl \entrally. Tlie female genital segments similar in structure tiiroughout llie subfamily (See tiguies I and II). (1-4) Sul>faniiiy Comontl\.\e Micklle coxiie with visible tiochantins. La- brum prominent, in great part visiliie. Tiie ab- dominal intercoxae process acute and triangular. Tile mentum moderately emarginate, tiie iiguia prominent and emarginate. Tiie apicaie of the male genitalia is elongate, several times as long BiOLex, the latter emarginate at middle; valvifer .short, tv\ic-e as long as wide, distinctly shorter than the apic-ale. Female genitalia elongate with bacula as supports in the valvifers; c-o.xites di- vided, stylus obsolete. (1-5) Subfamily Pedininae Body oval, not very convex; epistoma emar- ginate covering the base of the mandibles; la- bnun or upper lip prominent; mentnm generally trilobed in front, small; ligula or central part of the lower lip prominent; e\es transverse, some- times di\ided; eivtra embracing feebly the sides of the abdomen; middle coxae witli distinc-t trochantin; intercoxal process of abdomen trun- cate; anterior and sometimes the middle tarsi of the male dilated, and spongy beneath; hind tarsi sometimes pubescent and spinous. (1-6) Subfamily Op.\trinae Body o%'al, heud recei\'ed by the thorax as far as the eves, which are transverse, strongly emarginate and coarseh' granulated, epistoma emarginate, extending down o\er the m;mdib!es, labrum prominent, menhun small, ligula promi- nent, or slightlv emarginate, maxillae exposed; eivtra with narrow epipleurae (Fig. II), anter- ior coxae transverse or rounded. Biological Series, Vol. 6, No. 1, February, 1965 (1-7) Subfamily Texebrioninae Beetles of this subfamily have bodies that are elongated, head prolonged, not received in the thora.x as far as the eyes, which are trans- verse and emarginate, epistoma truncate, not separated from the labrum by a clypeiis. Anten- nae with eleven joints, external ones broadened; mentum small, elytra feebly covering the sides of the abdomen, epipleurae nanow; middle coxae with noticeable trochantin; legs long, tarsi clothed beneath with silky golden or coarse pub- escence. (1-8) Subfamily Helopinae Front of head with a leatheiy or horny mar- gin or a leathery band between the front and labrum; sides of the front obliquely elevated; eyes transverse, emarginate and coarsely granu- lated; antennae thickened externally; mentum small; ligula prominent; sides of the prothorax separated by a margin from the disk, elytra with narrow epipleurae; middle coxae with dis- tinc-t trochantin; tarsi slender, head not de- flexed. CHARACTERISTICS OF THE TRIBES, GENERA, AND SPECIES (1-1) Subfamily TENTYRIINAE Species from nine tribes of Tentyriinae are included in this report. Each tribe and the genera are characterized below. The species of each genus are described in the text of diis study. 1(1-1) Tribe Eurymetopini Middle coxae without trochantin; mentum very large, concealing both ligula and ma.xillae; anterior tibiae with two terminal spurs, not toothed externally near the middle; mandibles never grooved externally; posterior co.xae more or less separated, the abdominal process acute to broadly rounded; elytra not embracing the sides of the body, the inflexed parts occupied wholly by the epipleiira; mentiun hexagonal, apex emarginate or sinuate; front without a pro- longed epistoma clasped b\- tlie mandibles, the right mandible at least generallv with a tooth which clasps the labrum only. Antennae slender, outer four segments broader; scutellum well de- veloped; body generally winged, though often apterous. The following three genera, Metoponium, H ylocrimts and Steriphamis, each represented by a single species, were collected at the test site. 1(1-1) A. Genus Metaponiinn may be charac- terized as follows: Anterior tibia produced externally at tip; eyes large, head with a distinct supra-orbi- tal ridge or keel; epistoma never emarginate; mandibles ridged externally above; antennae slender, extending about to the base of tlie prothorax, last four joints broader com- pressed, the eleventh as long as the tenth or longer and pointed; scutellum distinct; elytra never strongly rugose and usually with dis- tinct serial punctures; tarsi beneath with long, stiff setae; protliorax generally fully as wide as the elytra. In 1907 Col. Casey described many species of Metaponium from Arizona and California. The senior author spent considerable time in June, 1964 studying the Casey collection and species of this genus. It is our opinion that the Casey complex of species in this genus must be revised before dependable reference to species of this genus ciin be made. We are therefore con- sidering sj>ecimens of this genus as canvexicolle LeConte 1(1-1)A-1. For a description of this species see page 16. 1(1-I)B. Genus H ylocrimts has the following characteristics: Anterior tibia not externally prolonged at tip, antennae long and slender, eyes large, not deeply emarginate; body elongate, par- allel; surface glabrous; tarsi with sparse, stiff setae beneath. A single species, laharans Casey, l(l-l)B-2, be- longing to this genus was collected at Mercury. Tlie species description is given on page 17. 1(1-1)C. Genus Steriphamis has the follow- ing characteristics: Body oval, convex, glabrous, devoid of hind wings; tarsi spinulose or sparsely and very coarsely setose beneath; normal, sub- cylindrical; the anterior nearly straight as usual; frontal margin generally feebly sinu- ato-truncate, not evidently biemarginate. A single sj>eeies, lubricans Casey l(l-l)C-3 is described on page 17. Bkk.iiam Vol'nc University Science Bulletin 2(1-1) Tribe Aucmmobiim Middle foxae witlioiit trotliantin; mentum ver\' large, concealing both ligiila and maxillae; anterior tibiae with two terminal spurs, not toothed externally near the middle; mandibles never gr(K)ved externally; posterior coxae more or less niirrowlv separated, the abdominal pro- cess acute to broadly rounded; elytra not em- bracing the sides of the body, the inflexetl parts oc-cupied wholly by the epipleura; mentiim hex- agonal, Nsnth the apex more or less distinctly emarginate; front with the epistoma (absolut- ely) prolonged; epistomal lobe not clasped by the mandibles, which are folded beneath it out of sight from above. Antennae gradually en- larged and c-ompressetl outvvardly. The onlv genus in this tribe is Auchmobius, 2(1-1) A, which was rc\'ised by Blaisdell in 1934. At this time he described seven new spec-ies. The Mercurv- species is considered b\' us to be suh- boreus Blai.sdcll 1(1-1 )A-4. See the text, page 17, for description of this species. 3( 1-1 ) Tribe Tiu.mytlni Similar to Auchmobiini except that the epis- tomal lobe is clasped by the superior external ridge of the mandibles; antennae filifonn, gen- erally with the last four joints larger; seutellum well developed as in Eurymetopini; body winged or apterous, the metastemum with or without ante-coxal grooves. 3(1-1) A. Genus Chilometopon has the follow- ing characteristics: Outer ridge of the mandibles very nar- row with a small dentiform protuberance at the base; body elongate, c-onvex glabrous, fully winged; eyes large, prominent and only slightly emarginate anteriorly; tarsi long, the basal joint of the posterior variable; pro- thorax alwa\s narrowed toward the base, and widest before the middle; last antennal joint elongate, sometimes extremely so. One species, abnorme (Horn) 3(l-l)A-5, is described on page 18. 4(1-1) Tribe Epnn.uaNi Middle coxae without trochantin; mentum very large, concealing both ligula and maxillae; anterior tibiae with two terminal spurs; not toothed extemalK' near the middle; mandibles never grooved externally; posterior coxae nar- rowly separated; al)doniin;il process acute to broadly rounditl; ehtra not embracing the sides of the body, mentiini trans\ersely parallelo- gramic, the apex very broadly arcuate from side to side and not sinuate at the middle, generally much more transverse. 4(1-1)A. Genus Melopoloba lias the follow- ing characteristics: Prosternum horizontally produc-etl poster- iorly, the tip received within a large deep mesosternal excavation; eyes large but not prominent, generally finely faceted and but feebly emarginate anteriorly; t;u-si with sparse, short, stiff spiniform setae beneath the jX)sterior, at least, devoid of denser and finer pubesc-ence; supra-orbital ridges strcmg, eyes coarsely faceted; body elongate, pointed behind, basal joint of the hind tarsi at least equal in length to the fourth and usually longer; sculpture rather coarse and sparse, surface polished. The species bifoss-iccps Casey 4(l-l)A-6, is described on page 18. 5( 1-1 ) Tribe Triorophini Middle coxae without trochantin; mentum large, concealing both ligula and maxillae; an- terior tibiae with two terminal spurs, not toothed externally near the middle; mandibles never groo\ed externally; posterior coxae narrowly separated, the abilominal process acute to broad- ly rounded; elytra embracing the sides of tlie body, the inflexed parts not wholly occupied by the epipleura. 5(1-1) A. Genus Trioiophus has the following chiu-acteristics: Epistomal lobe parallel, \er\' prominent, angulate at apex, clasped toward base by the swollen basal p;u-ts of the mandibles; the lat- ter stout, each with a strong dorsal tooth clasping the labrum; e\es trans\erse. emar- ginate anteriorK-; prothorax margined at the sides; elytra inflated, with abbre\iatrtl series of coarse punctiues, epipleura nanow; legs long, tarsi with sparse spinules beneath; lat- eral lobes of front tuberculate; sides of pro- notum with a distinct margiuid bend, its base not bisinuate. The species laeois LeConte, subspecies poli- tus Casey 5(l-l)A-7 is described on page 19. 6(1-1 ) Tribe Eduotini Middle coxae without trochantin. Mentum very large, concealing both ligula and maxillae; anterior tibiae uith terminal spurs, not toothed I'xternallv near the middle; mandibles ne\er grooved extern, illy: posterior coxae widely sep- Biological Series, Vol. 6, No. 1, February, 1965 axated, the abdominal process broadly truncate; mesostemum without ante-coxal grooves; the body wingless; elytra frequently costulate; mesostemum elevated, flat, abutting closely and on the same plane against the ape.x of the flat- tened prosternal process; hind co.xae tiansversely oval. 6(1-1) A. Genus Edrotes has the following characteristics : Body rounded, convex, with conspicuous erect hairs; head large, epistomal lobe quad- rate, with its sides parallel and sinuate, and apex broadly angulate nearly as in Trioro- phus; mentum transversely he.xagonal, the apex trisinuate; eyes small, convex, promin- ent, and imeniiu-ginate; antennae long and slender, outer joints larger, the eleventh p\ri- form and long; prothorax with prominent and acute apical angles, stronglv transverse; scutellum obsolete; elytra inflated and wide- ly embracing the body beneatli; epipleurae short; legs long, slender, the hind tarsi short, sparsely spinose and not at all grooved be- neath, with long flying hairs above as on the femora and tibiae externally; hind coxae transverse, separated bv less than their own width. Description of the species orbus Casey 6(l-l)A-8, is on page 19 of the text. 7(1-1) Tribe AjtAEOscHiziNi Middle coxae without trochantin; mentum generally small in size, never concealing both the ligula and ma,xillae; elytra without true epi- pleura; anterior coxae separated; antennae mod- erately long, thick, filiform and perfoliate, usu- ally scaley, free; legs short and stout. 7(1-1) A. Genus Araeoschiztis has the follow- ing characteristics : Body elongate, convex, hind bodv ped- unculate without humeral angles, the hind wings wanting; head elongate-oval, clypeus large; mentum rather large, flat, broadly truncate at apex; mandibles bifid at tip; eyes completely divided, coarsely faceted. The upper part elongate, sunken deeply be- tween the prominent lateral margin and a strong supra-orbital ridge; antennae about as long as the head and half the prothorax, prothorax cordate, small; scutellum triangu- lar sciu-celv passing the basal declivity of the elytra; coxae globular, moderately separated; legs short, stout, tarsi short, claws small, slen- der and arcuate. SulcicoUis Horn 7(1-1) A-9, which is a very common species in this area, is described on page 20. 8(1-1) Tribe Anepsiini Middle coxae with trochantin; labrum scarce- ly visible; tarsi spinose beneath; antennae not filiform; anterior tibiae broadly dilated. 8(1-1) A. Genus Anepsius has the following characteristics : Body rather stout, convex, glabrous; head trapezoidal, clypeus broadly and feebly sinu- ate towards the middle; eyes basal, more rounded and less coarsely faceted, usually divided by the thick anterior can thus; an- tennae slender, almost as long as the head and prothorax, third joint longer than the second; prothorax four-fifths wider than long; elytra equal in width to the prothorax, two and one-half times as long, oval, die sides evenly arcuate; legs short, slender, tlie an- terior tibiae broadly dilated at apex, with the spurs distinct; tarsi short, sparsely spinose beneath. Brunneus Casey 8(1-1)A-10 was the only species of tliis genus collected at Mercury. It is described on page 21. 9(1-1) Tribe Cryptoglossini Middle coxae with trochantin; labrum scarce- ly visible; tarsi spinose beneath; antennae not filiform; anterior tibiae slender. Eyes present; emarginate, reniform. Posterior margin of the last two abdominal segments semi-circularly emarginate. Two genera are represented in the speci- mens taken at Mercury. They may be separated by the following key: 1. Last antennal segment truncate, small- er than the tenth .. 9(1-1)A Cnjptoglossa 2. Last antennal segment oval, pointed, nearly as large as the tenth 9(1-1)B Centrioptera A description of the species Centrioptera imiricata LeConte, 9(1-1)B-12, is on page 23. Cnjploglossa verrucosa l>eConte, 9(1-1)A-11 is described on page 23. (1-2) Subfamily ASIDINAE Two tribes of this subfamily are represented in collections from the Nevada Test Site. 10 Biiic.iiAM ^<)i N(; L'niveksity Scienxe Bulletin 1(1-2) Tribe Asidim Btxlv o\ate, apterous; head narrowed beliind the eves, wliidi are transverse and kiilney-shap- ed; epistoma very short; mentuin large; an- tennae eleven segmented; elytra embracing widelv the flanks of the abdomen; epiplenrae indistinct, middle coxae with distinct trociiantin; metasternnm short, with tlic epistcrna wide; iiind coxae moderately separated; intcrcoxal process of abdomen obtuse; legs with tibial spurs dis- tinct; tarsi setose, but not sulcate beneath. Three genera are represented in this tribe. 1(1-2)A. Genus Pelccijphonis has the follow- ing characteristics: Mentum not entirely filling the buccal opening and always placed upon a rather evi- dent pedicle formed by a gular prolongation; ligula small, generally flat, angularly emar- ginate to subtnmcate and strongly retractile, usuallv hidden under the mentum, the latter alwa)s clearly separated from the closed mandibles; last joint of the ma.xillary palpi variable in size in the se.xes; prostemum de- fle.xed; body diversely sculptured, very much larger in size; tarsi with short and incon- spicuous spiniform hairs beneath; base of the prothorax truncate or arcuate-truncate; head and prothorax generally smaller, giving the body a markedly different habitus; elytra each with distinct ridges as shown in Figure XIII. Two species collected may be separated as follows: 1. Edge of pronotum unevenly scalloped, tuberculate, narrow; elytra very ven- tricose and tuberculate; outer coxa ra- ther fine but strong, the inner very fine and sulx)bsolete Fig. XIII, 1(1-2)A-13 pantcx Casey See page 24 for description. 2. Edge of pronotiun not scalloped, coarsely, sparsely ;iik1 uiu'vcnly punc- tured, the sides narrowly reflexed; elvtra elongate-oval, with distinct mar- ginal costa, each with three nearly straight parallel, moderately elevated costa, the surface between the suKire and first costa shining, the remainder opaque Fig. XIV, 1(1-2)A-14 semilaevis (Horn) See page 25 for description. 1(1-2)B. Genus Euschides has the following characteristics: Mentum not entirely filling the buccal opening and always placed upon a pedicle formed by a gular prolongation; ligula hu-ge, tumid, angularly incised; mentum always sep- arated from the closed mandibles, thus leav- ing the maxilliu-y cardo exposed in part; prosternum deflcxed posteriorly between the coxae; last joint of the maxillary palpi large and scalene in male, smaller in the female; base of the prothorax broadly lobed, bcc-om- ing anteriorly obhcjue toward the sides, basal angle obtuse, sometimes evident but never prominent. One species luctatus (Horn) 1(1-2)B-15 re- ported; see description on page 26 of text. 1(1-2)C. Genus Trichiasicla has the following characteristics: Mentum not filling the buccal opening and placed on a pedestal formed b\' a gular prolongation; Ugula large, tumid, angularly incised; mentum separated from the closed mandibles, leaving the ma.xillary cardo ex- posed in part, prosternum deflexed poster- iorly between the coxae. Last joint of the maxillary palpi differing but little sexually, never more than recti-triangular in the male; antennae more rapidly enliuged distall)-, the tenth joint with the usual two widely sep- arated tomentose spots at the tip; elytra with- out triie costae, the elevated lines when pres- ent having more or less the nature of narrow and accentuated obtuse ridges; body pub- escent; mentum small, gular pedicle long and well developed; antennae slender; basal angles of prothorax never prominent; anter- ior tibiae serrulate externally, the outer angle at tip strongly everted and acutely spiniform. One species acerbo (Horn) 1(1-2)C-16; see page 26 for description. 2(1-2) Tribe Cr.\nioti.\i Middle coxae without trochantin; mentum large, concealing both ligula and niiLxillae; an- terior tibiae with two terminal spurs, not toothed externalh' near the middle; posterior coxae wide- lv separated; the abdominal process broadly truncate; body wingless; elytra frequently cos- tulate; metasternnm not elevated, discontinuous with the prosternum; hind coxae small, oval, much abbreviated trans verselv; eyes finely fac- eted; legs long and slender; female genitalia of the compact type, which is Asidini in nature. 2(1-2) A. Genus Craniotus has the following characteristics; Biological Series, Vol. 6, No. 1, February, 1965 Body narrow anteriorly, inflated elytra; sparse to dense pubescence on the body; head small, projection at the sides anterior to the eyes extend beyond one-third the width of the head; transverse groove behind the epistome; mandibles bifid at tip, folding beneath the labrum; mentiim large, sinuate at apex and emarginate at base; antennae long and slender, the third segment much elongated, the eleventh not free but small and received within the apex of the tenth; prothorax transversely suboval; scutellum elongate; el)'tra embracing the sides of the body, epipleurae narrow, disappearing be- fore the middle of the abdomen; anterior co.xae separated; metasternum short, convex at the sides; femora and tibiae long, slender and subcylindric, hind tarsi rather short, slender, and with long hairs above and short stiff spines beneath. Female genitalia of the elongate type (Fig. XVII, 2-3). For description of the species, hlaisdelli Tan- ner 2(1-2)A-17, collected on the test site, see page 27. (1-3) Subfamily ELEODINAE Ventral segments three and four with cx)r- aceous hind margin; front entirely corneous; first joint of tarsi moderate or elongate, never very short tarsi, not compressed; eyes not prominent, more or less transverse, always emarginate in front; anterior tibiae alone or none dilated; pen- ultimate joint of tarsi entire; anterior coxae rounded; middle coxae with trochanter; an- tennae perfoliate, third joint longer than the following; hind coxae transverse, never oblique; fourth segment of maxillary palpus triangular or securiform; epipleura attaining the sutural angle; tarsi spinose or setose beneath; elytra widely embracing the body. 1(1-3) Tribe Eleodini Body oblong, apterous, head prominent; epistoma covering the base of the mandibles at the sides; labrum prominent; mentum small, trilobed, inserted upon a gular pedicle; max- illae e.xposed, maxillary palpi with the last joint securiform, not very large; eyes transverse, reni- form; antennae eleven jointed with the outer segments rounded, equal; elytra embracing wid- ely the flanks of the abdomen, epipleurae nar- row; middle coxae with large trochantin, side pieces attaining the coxal cavities; metasternum short, epistema narrow, epimera distinct; hind coxae widely separated; intercoxal process of abdomen rectangular; third and fourth ventral segments not prolonged behind at margin. Legs long; anterior femora frequently toothed; tibial spurs disHnet; tarsi channelled and setose be- neath. Key to the genera: 1. Sides of the epistoma not dilated, mar- gin straight or sinuate, converging anteriorly 2 Sides moderately dilated, margin ar- cuate 1(1-3)A Trogloderus 2. Epipleura attaining the humeral an- gles, broader at base, more or less gradually narrowing to apex, occupy- ing only a part of the inflexed portion of the elytra; buccal processes of the genae not produced ... 1(1-3)C Eleodes Epipleura very narrow, not attaining the humeral angles .. 1(1-3)B Emhaplnon 1(1-3) A. Genus Trogloderus has the follow- ing characteristics: Body elongate, rough, opaque; eyes trans- verse and renifonn; head pierced with closely set, small holes; front prolonged, covering the labrum, sides dilated and reflexed; surface briefly convex at middle, transversely im- pressed with a small deep fovea on the ver- tex; antennae with third segment as long as the two following; prothorax emarginate in front, rounded on the sides, basal angles pro- minent; disc coarsely oribate; elytra widi the suture and foin- costae each side acutely ele- vated; intercoxal process of first abdominal segment broader dian long; under surface strongly granulate; anterior femorae armed with a small to broad tooth; front tibiae curved and serrate on the outer edge; tarsi setose. Tills species, costatiis nevadus LaRivers 1(1-3)A-18 is described on page 29. 1(1-3)B. Genus Embaphion has the following characteristics : Thorax and elytra always acutely and sometimes broadly margined, margin more or less reflexed; epipleurae always narrow, rarely defined front (Figs. I and II) inflexed sides of the elytra, except at apex, where they are always well defined, not suddenly widened at base and never attaining the humeral angles of the elytra. Blaisdell made the following obsei-vation on the charac- teristics of this genus: "The above characters are distinctive of the genus and are not observed elsewhere in Eleodini." Biii(;iiAM VoLNc University Science Bulletin One species of this genus was collected at the test site. See page 29 of this report for a description of elongatum Horn, 1(1-3)8-19. Tlie genus Eleodes 1( 1-3)C has the following characteristics: Mentiim trilobed, middle lobe large and convex; apical joint of labial and maxillar)' palpi triangular; suture between epistoma and front distinct; eyes reniforni; antennae with ele%en segments, the last three usually compressed. Prothorax variable in shape and sculpture in some species prolonged into a cuada behind; epipleurae distinct. Legs fair- ly long, femora not strongly clavate, in some species ;irmed in one or both sexes with teeth. Tarsi usually channeled and setose beneath, spurs of the middle and hind tibiae well de- veloped. The genus Eleodes, because of the large niun- bers of species referred to it, has been separated into thirteen subgenera. For the list and char- acteristics of these subgenera see Tanner's paper (1961), Checklist and New Species of Eleodes, pp. 60-61. The species of Eleodes collected at the test site belong to six of the thirteen subgenera which may be separatt^d by means of the following key: Subgenus Mckinelcodes Anterior femora ai'med only in the male or mutic; anterior tibial spines dissimilar in the sexes; femora mutic. l(l-3)C-20 carbonaria iutinunis LeConte Tills is the only species of Mehneleodes we have collected on the test site. A description and discussion of the species will be found on page 29 of this rejiort. Subgenus Eleodes Anterior femora at least, anned in both sexes (except in caudifera and lon^ipilosa where teeth are abortive). Tlie species and subspecies of this subgenus may be separated as follows: 1. Body elongate; elytra strongly sulcate; intervals fjuite strongly convex, smooth, with a single series of irregu- larly, distantly spaced, feebly muri- cate punctures, which become de- cidedly muricate on the apical dtH.-liv- itv'. Sulci about e{|ual in width to the inter\als, with closely placed muricate puncturi's which become more densely plac-ed toward apex; iuflex sides of the eh'tra obsoletely sulcate and irregu- larly muricately punctured. Size, males, 25 to 31 mm in length; width 9 to 14 mm obscura stdcipeuuis Mann. 1(1-3)C-21 Description on page 30 of report. 2. Body large, oblong oval, black and shining; head twice as wide as long, punctation irregular, denser at the per- iphery. Antennae short and stout, reaching to the posterior fourth of the prothorax; third joint equal in length to the next two taken together; pronot- um widest at about the middle, disc smooth and shining, surface finely and sparseh' punctate, punctures arranged in distinct unimpressed series; epi- pleurae narrow, gradually narrowing from the base to the apex; abdomen sparsely punctate, with some reticulare rugosity; legs not long but stout; an- terior femora in both series armed with an acute tooth; female genitalia of the compact type (Fig. 11-4); size: males 26 to 29 mm in length, 10 to 12 mm in width; females, 27 to 30 mm in length, 10 to 12 mm in width. Figs. 1 and 2 grandicollis valida Boh. l(l-3)C-22 Description on page 31 of report. 3. Body elongate, ovate, integument dull and thick, black in color, frequently reddish along the suture; head and thorax more or less shining. Elytra slightly convex, sulci opaque and deep, intervals strongly convex and shining; antennae long, reaching the base of the prothorax; pronotimi widest at the middle; disc smooth, fineh' sparsely punctate; epipleurae gradually narrow- ing from base to apex; abdomen smooth, finely punctulate and rugu- lose; fifth segment more strongly punctate; legs slender; anterior femora armed with an acute tooth in both sexes. Size: males IS to 22 mm in length, 7 to 9 mm in width; females 19 to 24 mm in length, 8 to 10 mm in width ' hispihihris sctdpldis Blais. l(l-3)C-23 Description on page 32 of text. 4. Body elongate, siniace sparsely clotli- ed with long, black hairs; caudate; iongipdosa Horn l(l-3)C-24 Description on page 32 of report. 5. Bod\' large, elongate suI)o\al to sub- Biological Series, Vol. 6, No. 1, February, 1965 13 fusiform-ovate; dull black in color, all the femora armed with long acute spines; elytra moderately striate armata LeConte l(l-3)C-25 Description on page 33 of te.xt. 6. Body smaller, punctation fine and sparse, except on head; pronotiim slightly wider than long, sides almost straight. Femoral teeth smaller and acute .... armata piimila Blais. l(l-3)C-26 Description on page 33 of text. Subgenus Metablapylis Anterior tibial spurs similar in the sexes. Tarsi similar in the se.xes, or nearly so. Middle lobe of the mentum small; anterior tarsi compar- atively simple beneath, groove entire. Lateral lobes of the mentimi fully exposed; sculpturing comparatively simple; femora mudc. The two following species of Mctablapijlis may be characterized as follows: 1. Body elongate, usually about three times as long as wide. Head less than twice as long as wide, antennae mod- erate in length; eleventh segment ov- ate, truncate at tip; pronotimi widest at or just in front of the middle, sur- face finely, densely and irregularly punctate, elytra widest at the middle, surface with fine punctures, usually arranged without order, and more or less striate; epipleurae widened be- neath the humeri, then gradually nar- rowing to apex; legs moderate in length, mutic and stout nigrina LeConte l(l-3)C-27 This species is described on page 34 of this study. 2. Bodv clyindrico-fusiform, black, some- what depressed, smooth, elytra striae rather distant; pronotum finely, but distinctly and sparsely punctulate; tibiae and tarsi with reddish-brown setae; spinules and tarsal claws strong- ly developed dissimilis nevadensis Blais. 1(1-3) C-28 Description of this species on page 34 of this report. Subgenus Steiteleodes Anterior tarsi dissimilar in the sexes. Species not usually pubescent, rarely so. Form elongate usually large; first joining of the anterior tarsi slightly thickened at tip beneath, bearing a small transverse tuft of yellowish or brownish modi- fied spinules which interrupt the groove in the male; simple in the females. The following is a brief characterization of the only species of Steneleodes taken at the test site: Body elongate to elongate fusiform, black head twice as long as wide, finely punctate; antennae stout, pronotum wid- est at the middle; disc evenly convex, sparsely punctulate; sides finely margin- ed; elytra elongate; base truncate; humeri obtuse; surface irregularly and evenly punctate; epipleurae rather wide at the humeri, gradually narrowing to apex; fe- mora not denselv punctate, the anterior mutic in both sexes longiroUis LeConte l(l-3)C-29 For further discussion of this species see page 34 of this report. Subgenus Bhiptjlis Form short ovate, moderate in size to small, robust (elongate and depressed in tibkdis); an- terior tarsi of male with first two or three joints feebly thickened at tip beneath and clothed with dense silken or brownish tufts, obliterating the groove; joints simple \\ith grooves entire in female, femora mutic. The two species of this subgenus may be separated as follows: 1. Body oblong-oval, two-and-a-thtrd times longer than wide; head twice as wide as long; antennae with four outer joints feebly compressed, third joint equal to the next tv\'o taken together; pronotum finely and densely punc- tate, widest at the middle and evenly arcuate from apex to base; elyti-a sculpturing consisting of small shiny tubercles arising from an opaque base tenehrosa Horn l(l-3)C-30 Description on page 34 of report. 2. Bodv robust, convex, coarsely and densely sculptured; color dull black, legs dark brown; head large, two-thirds as wide as the prothorax, densely pimc- tate; antennae longer than the head and prodiorax, thiid joint four times as long as wide; prothorax evenly convex, coarsely, deeply and confluently punc- tate; elytra coarsely, densely, asperat- ely punctate hrunnipes brevisetosa Blais. 1(1-3)C-31 See page 35. 14 Subgenus Lilheleodes Form ovati', iiKKlerate in size, less robust; first joint of the anterior tarsi more or less thickened and slightly more prominent ventrally than the others, pubescent tuft variable, most evident in extricato: male first joint with a min- ute tiift of silken pubescence at tip beneath. l(l-3)C-32 extricata frigida LaRivers This is the only species of Lithcleodes thus far taken at the test site. For additional com- ments on it see page 35 of this report. (1-4) Subfiimily CONIONTINAE 1(1-4) Tribe Comontim Body oval or globose, apterous; epistoma covering the base of the mandibles; labrum prominent; mentum moderate, emarginate; gu- lar penduncle short or almost obsolete; ligula prominent, emarginate; maxillae e.vposed; eyes transverse, small elytra usually with narrow epi- pleurae; anterior co.xae subtransverse; middle c-o.\ae with distinct trochantin, side pieces of mesothorax attaining the coxal cavities; meta- stemum short; hind coxae approximate; inter- coxal proc-ess of abdomen acute; tibial spurs long, tarsi spinous beneath; tlie first joint of hind tarsi long. 1(1-4)A. Genus Sphaeiiontis has the follow- ing characteristics: Elytra widely embracing the sides of the body, the epipleura variable; anterior tibiae with e\'erted external angle at apex; basal joint of anterior tarsi long; prothorax alwavs prolongwl at the sides and envelop- ing the humeri: scutellum nearly obsolete; epipleura narrow, occupying much less than the entire inflexed sides of the elytra; epi- pleura gradually becoming wider basally, sometimes extending to the sides of the elytra at base; sides of the elytra always obtusely rounded in sections, ne\er acutely margined; antennae slender, dilated apically; intercoxal process obtuse, the coxae more widely separated throughout; body more broadly rounded, ver\ convex, the sculpture more muricate; propleura with more con- spicuous hiiirs. DiUitata LeConte l(l-4)A-33 is the only species of this genus c-oUected at the test site. Description of this species is on page 35 of report. 1(1-4)B. Cenus Eusattiis has the following characteristics: Briciiam Young University Science Bulletin Similar in characteristics to Sphaeru>Htis except the interc-oxal process of the abdomen is acute, the coxae throughout narrowly sep- arated; body oblong-o\al to parallel, mod- erately convex; propleura with or without bristling hairs. Two species of this genus, dubius and agna- tiis, collected at Mercury may be separated as follows: 1. A small species; length 7.8 to 8.5 mm; width 4.2 to 4.6 mm. Body elongate, convex, polished; prothorax i\vo and one-half times as wide as its median length; elytra narrow and elongate, al- most a third longer than wide, punc- tures fine, but distinct; anterior tibiae only feebly serrulate externally dubius LeConte l(l-4)B-34 For further information on this species see page 36 of this report. 2. A larger species; length 8.9 to 9.8 mm; width 5.1 to 5.7 mm. Body broadly ob- long-o\'al, moderately convex, subglab- rous; prothorax not two and one-half times as wide as its median length; elytra elongate, as wide as the pro- thorax, parallel, surface feebly rugose, wiih sparse small muricate punctures; anterior tibiae strongly sinuate exter- nally beyond the middle .' ' agnaius Casey l(l-4)B-35 This species is discussed on page 36 of the report. 1(1-4)C. Genus Coniontis has the following characteristics: Elytra narrowly embracing the sides of the body, the epipleura constantly narrow and oc-cupving the entire inflexed piu^t; the basal joint of the anterior tarsi short, obli(]ue- ly truncate at tip; prothorax \ariable at base, but generally more truncate; scutellum well developed, trianguUu-; posterior angles of the prothorax strongh* posteriorly produced; palpi more elongate than usual, last tliree joints of the antennae moderately dilated; basal joint of the anterior tarsi longer than the next t\vo combined; obli(|ucly prominent internally at tip, tvvo to four transverse, rap- idly diminishing in size. Nevadensis carsonica Casey I ( l-4)C-36 is the only sj>eeies of this genus c-ollected at the test site. See page 36 of the text for descrip- tion of the species of this genus. Biological Series, Vol. 6, No. 1, Febbuarv, 1965 15 1(1-4)D. Genus Coniontellus has the follow- ing characteristics: This genus is similar to Coniontides, ex- cept that the posterior angles of the pro- thora,\' are feebly produced posteriorly, the thoracic base frequenth' subtiuncate; eyes completely divided; body smaller, the legs and antennae shorter. A single species of Coniontellus argtitus Casey, l(l-4)D-37 was collected. See page 37 of text for species description. (1-5) Subfamily PEDININAE 1(1-5) Tribe Blapstini Body oval; eyes completely divided; epistoma emarginate, the inflexed part of the elytra is composed entirely oi the epiplemae; mentum not trilobed in front; dilation of the anterior tarsi of the male feeble; presence or absence of a fringe of setae along the lateral edges of the body. 1(1-5) A. Genus Bkipstinus has the following characteristics: Scutellum triangular, separating the ely- tra at base, the hind wings frequently well developed and the anterior tarsi of the male dilated as a rule; base of the prothorax bi- sinuate; anterior tibiae straight; pubescence simple; body usually oblong or oblong-oval, the sides not fimbriate; anterior tibiae simple. Two species of this genus may be separated with the aid of the following: 1. Small species. Length 5.0 to 5.1 mm, width 2.5 to 2.6 mm. Color nigra pice- ous, frontal margin, labrum and legs more or less rufous; pubescence fairly dense, decumbent and confined to the intervals; head small widest just before the eyes; epistome emarginate over the labrum; pronotiim about two-fifths wi- der than long; disc densely and evenly punctate; elytra twice as long as wide; striae distinct, punctures small; legs moderate in length and stoutness vandykci Blais. l(l-5)A-38 See page 37 of report for discussion of this species. 2. Large species. Length 6.4 to 6.5 mm. Width 3.0 to 3.1 mm. Color deep red- dish browai; pubescence yellowish, dense and decumbent on head, pro- thorax and elytra; upper portion of eyes large, round and flat; punctation on head and prothorax dense and deep; distal three segments large and oval; legs moderate in length, first and fourth tarsal segments about equal in length pubesccns LeConte 1(1-5) A-39 This species is discussed on page 37 of this report. 1(1-5B. Genus Notihtis has the following characteristics: Eyes entirely divided; scutellum very short and broad, not entering the disc of the elytra; apterous; male tarsi not dilated; prothorax laterally densely fimbriate; anter- ior tibiae broadly triangular and com- pressed; body stout, oblong-oval. One species, Notihhis stibstrintus Casey l(l-5)B-40, described on page 37 of this study. 1(1-5)C. Genus Conihiosoma has the follow- ing characteristics: Eyes entirely divided; scutellum very short and broad, not entering the disc of the elytra; apterous; male tarsi not dilated; pro- thorax laterally densely fimbriate; anterior tibiae n;irrow, non-fossorial; body narrow and parallel. Conihiosoma elongatum (Horn), 1(1-5)C-41. A description of this monotypic species will be found on page 38 of this text. (1-6) Subfamily OPATRINAE 1(1-6) Tribe Leichenini Specimens of this tribe have the fourth seg- ment of the maxillaiy palpus elongate-oval; more or less finely acuminate. 1(1-6) A. Genus Anemia has the following characteristics: Anterior tibiae not bent; vestiture not composed of short coarse recumbent hairs and long, erect, very robust bristles; anterior tibiae strongly dentate or produced exter- nally at or near the apex; eyes completely divided, or extremely neai-ly so; epipleura entire; anterior tibiae short, triangular. This genus is also a monotypic one. See page 38 for description of Anemia californica Horn, 1(1-6) A-42. BlIIGIIAM YoL'NC UiNlVEHSITV SCIENCE BULLETIN (1-7) Subfamily TENEBRIONINAE 1(1-7) Tribe Tenebbionini Body elongate, apterous, or winged, head prolonged; front dilated on the sides, covering the base of the mandibles; antenn;ie gradually thickened externally; elytra embracing feebh the sides of the abdomen; anterior coxae globose; legs long, tibial spurs small; hind margin of third and fourth ventral segments subcoriac-eous. 1(1-7) A. Genus Coeloctteviis has the follow- ing characteristic-s : Tarsi with fine, usually silken pubescence beneath; outer segments of antennae with disc-like expansions connected by a stock passing nearlv through their centers; anten- nae shorter than head and thorax; epipleura not attaining the tips of elytra; intercoxal process of abdomen broad, tnmcate. The description of C. punctata LeConte, l(l-7)A-43 will be found on page 39 of this study. 1(1-7)B. Genus Alaephus: Tarsi spinose or setose beneath; antennae elongate, slender, palpi long, tarsi slender; mentum emarginate. A single species of this genus taken at Mercury is closely related to paUidus Horn. See page 39 of this text for descTiption of Alaephus nevadensis Tanner n. sp. l(l-7)B-44. 1(1-7)C. Genus Eupsophulus: This genus is similar to Alaephus differ- ing in that the menturn is truncate in front. One species, castaneus Horn l(l-7)C-45. See page 40 for description. (1-8) Subfamily HELOPIN'AE 1(1-8) Tribe Helopini 1(1-8) A. Genus Helops: Body glabrous. Outer segments of anten- nae compressed; labriim prominent, clypeal membrane always visible; head usually pro- longed behind the eyes; elytra feebly em- bracing the body. Epipleurae entire, anterior coxae globuhir; tarsi densely pubescent be- neath; mesostemum short; intercoxae pro- cess broad or oval, never acute at tip. One apterous species attenuatus LeConte, l(l-8)A-46 is described on page 40 of tliis study. SYSTEMATIC AND ECOLOGICAL DISCUSSION OF THE SPECIES OF TENEBRIONIDAE COLLECTED AT THE NEVADA TEST SITE 1(1-1)A-1 Metoponium convexicolle LeConte References. LeConte, Ann. Lye. N. H. N. Y., V, 1851, pp. 125-216. Casey, Proc. Wash. Acad. Sei., IX, 1907, p. 309. Morphological Characteristics. Length 6 to 7..5 mm; form stout; oblong; rather convex; chestnut brown to deep reddish black. Head somewhat coarsely and closelv punctate; supra- orbital carina prominent. .Xntcnnae fairly long and slender, the last four segments lightly com- pressed and dilated. Pronotuin about as wide a.s the elytra; rather evenly iircuate, converging slightly more anteriorly than posteriorly; punc- tures strong laterally and becoming finer med- ially; scutellum transverse and oval. Elyti"a ob- tusely rounded at tip; coarse punctures in series which bec-ome confused toward the base. Legs short and stout. Plant Community Relationships. A total of 277 specimens was collected. These were most abundant in the distiu-bed Crayia-Lycium with about one-ninth this number in Larrea-Fran- seria and one-fourth in Salsola. A few were collected in the Crayia-Lycium and Mixed com- munities, but none was found in Atriplex- Kochia, Coleog\'ne, or Pinvon-Juniper. Seasonal Activity. This species was collected from February to December, but was most abundant from April through June. There was a decline in numbers collected during July and .August followed by another population peak in September and Octolwr. In the disturbed Gravia- Lvcium the jx^riod of acti\ity was from Febru- ary through December, whereas in LaiTea- Franseria, Lvcium, and Salsola it did not begin until March and .\pril and lasted only until October. In the Larrea-Franseria, activity of this species stopped in August. Comments. At the time Casey (1907) estab- lisluxl this genus he was the author of all its Biological Series, Vol. 6, No. 1, Febhu.^ry, 1965 members except two species, M. abnorme and M. convexicolle, which had previously been named by LeConte. Since then, Blaisdell des- cribed four more species. Because Casey be- lieved that there was little or no variation in a species, he named many new ones that today are considered synonyms. Representati\es from our series were studied bv Dr. Spilman at the National Museum and the senior author who compared them with the specimens in the Casey collection. Until tliis genus is revised and the validity of the Casey species determined, we propose to report this species as convexicolle. This was the ninth most common species at the site. l(l-l)B-2 Hylocrimis lahorans Casey Reference. Casey, Proc. Wash. Acad. Sci., IX, 1907, p. 337. Morphological Characteristics. Length 6 to 8 mm; oblong-oval, rather convex; varies from dull to shining; reddish brown. Head finely and densely punctate; slight supra-orbital carina; eyes large, protruding, and entire; antennae reaching the base of the pronotum. Pronotum finely and densely punctate throughout; anter- ior apical angle short and broadly acute. Elvtra wider than pronotum; twice as long as wide, punctures feeble, close-set, and arranged in lines between the intervals. Legs slender, relatively short compared to the body. Plant Community Relationships. A total of 31 specimens was collected The greatest num- ber occurred in the Grayia-Lycium community, with about two-thirds of this number in the Lycium and Mixed communities. Disturbed Grayia-Lycium areas supported slightly fewer than half, whereas Larrea-Franseria had only one-third as many as Grayia-Lycium. Salsola had one-ninth as many as disturbed Grayia- Lycium. Tliey were not found in Atriplex- Kochia, Coleogyne or Pinyon-Juniper. Seasonal Activity. This species first appeared in June. Beetles were most abundant during June and July, and persisted in smaller numbers until December. In August there was a decline in activity which increased again in September. Observed activity ceased in September in all communities except the Mixed. There was no apparent activity in October or November but in December activity was noted again in the Mixed community. Comments. This genus was established by Casey ( 1907 ) to contain sixteen species he described from the Great Basin and contiguous areas. A comparison of specimens in question was made by the senior author with the Casey species. It is most difficult to differentiate be- tween the species of the kiborans group from the Utah-Nevada areas. Without an anatomical study we conclude that the Mercury specimens should be considered as lahorans. l(l-l)C-3 Steiipliauui liibricans Casey Figure IX-H Reference. Casey, Proc. Wash. Acad. Sci. IX, 1907, p. 345. Morphological Characteristics. Body nar- rowly oval, convex, dark piceous, legs pale ru- fous; head deeply and closely punctate; sides converging and arcuate, prothorax two-thirds wider than long, basal angles obtuse and shghtly blunt; punctures stiong and fine, becoming dense and longitudinally confluent toward the sides; scutellum broadly rounded; elytra nearly one-half longer than wide, the sides parallel, punctures small but deep; abdomen sparsely punctulate medially. Length 5.1 to 6.2 mm; width 2.3 to 2.7 mm. Plant Community Relationships. Four speci- mens were collected in a Grayia-Lycium com- munity between March 29, 1960 and April 17, 1961, and one in the Atriplex community on August 22, 1960. 2(l-l)A-4 Auchmobius subborcus Blaisdell Figure.s III; IV-D; XV-E Reference. Blaisdell, Trans. Am. Ent. Soc, LX, 1934, p. 254, pis. IXII, IVII, and IVIII. Morphological Characteristics. Length 9.1 to 10 mm; width 4.3 to 4.8 mm. Form oval, tvv'ice as long as wide; color black, labrum and palpi ru- fous, also legs and apical antennal segments; sides of epistoma straight and convergent; sur- face of head evenly punctate; mentum about one-half wider than long; maxillary palpi slen- der; antennae attaining the pronotal base. Pro- notum twice as wide as long, widest at the mid- dle; disk convex from side to side, rather evenly punctate, punctures as on the frons. Elytra a third longer than wide, about three Hmes as long as the pronotum. Disk punctation rather dense, fine and not distinct, more evident lat- erally and apically; legs moderate in length and slender; metatarsi more than two-thirds as long as the tibia. Plant Community Relationships. Twelve specimens were collected in Grayia-Lycium communities between March 31, 1960, and Aug- 18 BiiiciiAM YoLNc Univebsity Science Bullct-in Figure III. Auchmobius mbboreux BUiisdell. ust 18, 1961. Eleven of the twelve vi'ere collect- ed in 1960 in March, June, July and August. The othcT one was collected in .August, 1961. Twenty specimens were collected in Larrea- Franseria communities between July 9, 1960, and September 5, 1961, all but four in June, July, August and September, 1961. The otlier four were taken in July, 1960. One was ct>!lected in a Pinyon-JuniptT com- munity on August 11, 1961. Eight were collec-ted in a Mixed community in the months of Julv, August and September, 1961. 3(l-l)A-.5 Chiloinctopon ahnoniw (Horn) Figures V-B; XV-G References. Horn, Trans. Amer. Ent. Soc., v. 1S74, p. 31. Casey, Proc. Wash. Acad. Sci., 1\, 1907, p. 372. Morphological Characterish'cs. Length 5.5 to 7 mm, form oblong; body slight; chestnut brown. Ne;u- coarsely and denscl\- punctate; eyes liu-ge, prominent, and snbcntirc. Last segment of an- tennai" as long as tiie next two together. Pro- thorax broader than long; narrower at apex than base; coarsely and densely punctured especially toward the margins. Elytra wider than the pro- notum; elongate-oval; sulci with finely muricate punctures. Legs m(xlerately long and slender, the tiu-sal claws long and arcuate. Plant Community Relationships. \ total of 17 specimens was ct)llectc>d. They were found most abundanth- in the Larrea-Franseria and .\rtemisia communities with one-fifteenth that amount in Grayia-Lycium and only a few found in the Lycium, Salsola and Mixed c-ommunities. Tlie\- apparently were not present in die .\trip- lex-Kochia or Coleogyne. Seasonal Activity. These beetles occurred from .-Vpril to .August with greatest abundance in Julv and .\ugust. They were first collected in April in the Mi.xed community, .\ctivity in Gravia-Lvcium began in June, whereas in other c-ommunities no activity occurred until July. 4( l-nA-6 Metapuloba bijossiceps Casey Figures IX-E; XIX-L Reference. Casey. Proc. Wash. Acad. Sci., IX, 1907, p. 413. Moqjhological Characteristics. Length 6 to 7 mm; elongate; fusifoiTii; polished; subglabrous; deep brown to nearly black. Head coarsely, irregularly, and spiu-sely punctate; supraorbital carina prominent, last four antennal segments dilated and compressed. Pronotnm trapezoidal; truncate apicallv and bisinuate basally; coarsely punctate. Elvtra bisinuate b;isally; coarsely punctate; broadly arcuate at the sides; blunt humeri; slightly widest behind middle; sparse irregular pimctures throughout; scutellum wider than long. Legs rather slender, not long com- pared to the length of the specimen. Plant Community Relationships. A total of 15 specimens was collectixl. The greatest num- ber (Kcurred in the Grayia-Lycium, with about three-fifths in the Coleogyne. A small number was found in the Mixed community. No speci- mens were collected in Larrea-Franseria, Ly- cium, .\triplex-Kochia, Salsola or Pinyon-Juniper. Seasonal Activity. This species was active only in JuK- in the Coleogyne and Mixed com- munities, whereas in the Grayia-Lycium and disturbed Gra\ia-Lycium communities acti%at}' continued through August. The numl>er of spec- imens collected in each of these two months was almost identical. Comments. Only a few M. hifossiceps were collected in the can traps. Most of them were taki'M while fivding on Atiiplcx coiifciiifolia Biological Series, Vol. 6, No. 1, February, 1965 19 (A) ALAEPHUS NEVADENSIS (8 ) ANEPSIUS BRUNNEUS AR AT-KO CO GR-LY LA-FR LY MIXED PI-JU SA & ( c ) ARAEOSCHIZUS SULCICOLLIS n^ (D ) AUCHMOBIUS SUBBOREUS Figure IV. Number of specimens by species (A-D) found in nine plant communities. (In this ixnd succeeding figure references to plant communities, tfie sy-mbols stand for the following: AR = Artemisia, AT-KO = Atriple.\-Kochia, CO = Coleogyne, GR-LY = Grayia-Lycium, LA-FR = Larrea-Franseria, LY = Lycium palli- dum, MIXED = Miscellaneous, PI-JU =Pinyon-Juiuper, SA = SaLsola.) during the middle of the day. A di.stinctive species. 5(l-l)A-7 Triorophus lacvis politus Casey Figures IX-I; XX-F References. LeConte, Ann. Lye. N. York. V, 1851, p. 141. Lacordaire. Gen. Col., V, 1859, p. 48. Horn, Trans. Amer. Pliil. See, XIV, New Series, 1870, p. 259. Casev, Proc. Wasli. Acad. Sci., IX, 1907, p. 435. Morphological Characteristics. Length 7 to 8 mm; elongate in form; color varies from chest- nut brown to nearly black, most commonly very deep reddish-black. Head almost as wide as pronotum; sp;u-sely punctate; two supraorbital folds at each side; antennae stout, with the tenth segment as long as wide. Pronotnm punctate with stiff yellow pubescence. Elytra elongate- oval; strongly inflated; punctures arranged in nine series. Legs long and slender; tarsi spinous beneath. Plant Community Relationships. A total of 867 specimens was collected. The greatest num- ber was found in the Grayia-L\'ciimi, with about four-fifths of this nimiber in Larrea-Franseria. They were about two-fifths as abimdant in Ly- cium, whereas the Atriplex-Kochia and Mi.xed communities supported about one-fifth as many specimens as the disturbed Gra\ia-L\cium. In the Coleogvne community they were one-tentli as abundant, whereas in Salsola they were about one-thirtieth as abundant. Tlie species was not found in Pinyon-Juniper or Artemisia. Seasonal Activity. This species occurred in large numbers from April to October with single specimens collected in December, January and March. They were most abundant in May and declined steadily from then until October. In all communities beetles became active in April e.xcept in Salsola, where they were inactive un- til June. In Atriplex-Kochia they were active imtil June. Activity stopped in the Mixed com- munitv in August, whereas in Lycium and Col- eogyne, activity continued through September. In the other communities they were active through October. 6(l-l)A-8 Edrotcs orhiis Casey Figures VI-A; XVI-D References. LeConte, Ann. Lye. N. York, V, 1951, p. 140. Lacordaire, Gen. Col., V, 1859, p. 31. Casey, Proc. Wash. Acad. Sci. IX, 1907, p. 451. LaRivers, Ann. Ent. Soc. Amer., XL, No. 2, June, 1947, pp. 318-327. Morphological Characteristics. Length 7 to 9 mm; form very round; convex; smooth; cov- ered with short, erect, ashy-white hairs; varies from dull, grayish-black to highly polish, deep 20 BrICHAM VoUNC UNIVEaSlTY SCIENXE BULLETIN I AR I AT-KO I CO I GR-LY | LA-FR I LY |miXEO I PI-JU 143? (A) CENTRIOPTERA MURICATA ( B ) CHILOMETOPON ABNORME (C ) CONIONTELLUS ARGUTUS ( D ) CONIBIOSOMA ELONGATUM ( E ) CRANIOTUS BLAISDELU ( F ) CRYPTOGLOSSA VERRUCOSA Figure V. Number of specimens by species (A-F) found in nine plant communities. black. Head much narrower than the pronotum; the front very narrow. Pronotum four times wid- er than long; apical angle verv- acute and ex- tended; well-separated hiberciilate punctures. Elytra at least one and one-half times v\ider than pronotum; the punctures are minute and sparse; each puncture is behind a small abrupt tubercle. Legs fairly long; the hind femora reach the end of the abdomen. Plant Community Relationships. A total of 2,(K)5 specimens was collected. The greatest niunber occurred in Gravia-lA'cium, whereas over half the number occuiTed in Salsola and one-third in Colcogync. In Larrea-Franseria they were one-third as abundant, whereas Lycium supported only one-fifteenth as many. A few specimens were collecttxl in the .\triplex-Kochia and Mixed communities, but none was present in Pinyou-Juniper and Artemisia. Seasonal Activity. This species was active the year roimd in disturbed Crayia-Lycium, with the months of greatest acti\itv being Feb- ruary, March, April and May. Months of least activity were June, July, November and Dec- ember. Activity increased during the months of Januarv, .'Vugust, SeptemlK'r and October. In the ri-st of the plant communities this species was acti\e verv little or not at all tluring Nhn-. June and Julv. The greatest {X'riod of activity in Larrea-Franseria and Lycium was during January and Febniarv, where;is in the .^triplex- Kochia, Salsola and (loleogN ne communities the period of greatest ac-ti\'it)' was in March. In these latter three communities there was little or no activity during November and December. 7(l-l).\-9 Araeoschiziis sulcicollis Horn Figures IV-C; XV-D References. Horn, Trans. Amer. Phil. Soc., XIV, New Series, 1870, p. 274; Trans. Amer. Ent. Soc, SVII, 1890, p. 341. Casev, Proc. Wash. Acad. Sci., IX, 1907. p. 488. Morphological Characteristics. Length uni- formly 4 mm; body fonn slender; elytra flat- tencxl; dark rcnldish-brown with light vellowish scales. Head huge; much elongated; converging from antennal prominences to basal angle; eves divided, elongate and narrow above, small round beneath; anteimae long; ver\' stout and compressed; the eleventh segment ver)' small and almost hidden in the apex of the tenth; cov- ered with \ellowish scales. Pronotum \er\' small; widest anteriorK"; sulcate along the middle from ajx'x to base; sides fringed with dose-set. \ellow scales; the .sulci deeplv punctate. Legs fairlv short and stout with no spines. Plant Community Relationships. A total of 2,fi64 specimens was collected. Tlu'V were found in greatest iiumlxT in the Coleogsne and were onl\' slightK' less abundant in the Larrea-Fnm- seria and Grayia-Lvcium coinnnmities. They were about three-fifths as abmidant in Lycium as in Coleog\'ne. A few specimens were cx)llected Biological Series, Vol. 6. No. 1. Febru.\ry, 1965 21 I AR I AT-KO I CO I GR-LY I LA-FR | LY | MIXED I PI-JU I SA I (A) EDROTES ORBUS 1745 1120 *•;•.■'■-'■'•.•'■'■'• ( B ) ELEODES ARMATA Figure VI. Number of specimens by species (A-B) found in nine plant communities. in Atriplex-Kochia and Salsola, wliereas none was found in the Pinyon-Juniper or Artemisia. Seasonal Activity. This species occurred all the year round, being most abundant in Septem- ber and April. The numbers declined in May, June and July, then increased in abundance tlirough August to the population peak in Sep- tember. Activity declined from October to Feb- ruary. In the disturbed Grayia-Lycium, Grayia- Lycium, and Mixed communities activity was evident every month of the year. In Coleogyne there was activity each month except December and February. Beetles were not active in the Larrea-Franseria community in January and February or in Lyciuin from December through March. In Salsola this species was taken in small numbers in May, June, September, October and November, whereas in Atriplex-Kochia it was collected only in July. It was not present in the Pinyon-Juniper. 8(1-1)A-I0 Anepsiiis hrunneus Casey Figures IV-B; XV-B Reference. Casey, Proc. Wash. Acad. Sci., IX, 1907, p. 506. Morphological Characteristics. Length 4 to 4.5 mm; elongate; convex; reddish brown; shin- ing. Head large; trapezoidal; stronglv and closely aspcrato-punctate; eyes completely divided with the upper lobe large and elongate; antennae long and slender. Pronotum wider than long; the an- terior angles acute and prominent; finely punc- tate. Ehtra slightly wider than the prothorax; humeri obtuse and distinct; very finely punc- tate in series. Legs fairly short and slender. Plant Community Relationships. A total of 39 specimens was collected. They were most abundant in disturbed Grayia-Lvcium, and about one-sevendi as abundant in Lycium and Grayia- Lycium. A few specimens were taken in the Salsola, Coleogyne and Mixed communities. They were not found in Larrea-Franseria, Atrip- lex-Kochia or Pinyon-Juniper. Seasonal Activity. This species was active from March through November, and most abun- dant in May. Beetles were about one-fourth as abundant during March and June as in May, with very few specimens collected in April and July through November. In disttnbed Grayia- Lycium they \vere collected from March through June, and September through Noven)ber. In the Lycium community they occurred in July and August, whereas in Grayia-Lycium they were active in May and June. In Coleogyne there was activity during April, during May in Mixed, and July in Salsola. (A ) ELEOOES BRUNNIPES BREVISETOSA lillK.MA.M VoL'Nf: l.'M\fc;H.sll V SCIENCE BULLETIN AR f AT-KO I CO I GR-LY I LA-FR I LY | MIXED | PI- J U | SA | (B) ELEOOeS CARBONARIA IMMUNIS —2J- (C ) ELEODES EXTRICATA FRIGIDA (D) ELEODES DISSIMILIS NEVADENSIS (E) ELEODES GRANDICOLLIS VALIDA , .69fe , 27 II 7 •"""^'^ },'.^-. ■■■! '— "^-""^ . ...J Figuri- VII. NumlxT of specimens by species (A-E) found in nine plant communities. I AR I AT-KO I CO I GR-LY I LA-FR I LY I MIXED | PI-JU | SA (A) ELEODES HISPILABRIS SCULPTIUS ^. .^.^ . . .. H c ( B ) ELEODES LONGICOLLIS ( C ) ELEODES NIGRINA ( D ) ELEODES OBSCURA SULCIPENNIS 27 7 ( E ) ELEODES LONGIPILOSA t F ) ELEODES TENEBRCSA (G ) EMBAPHION ELONGATUM 10 p" 1 10 7 20 f.■.■■^.^■.^.V■;^T7^%?l Figure \Ili Xuiulxr of specimens by species (A-C) found in nine pl.mt communilic JioLociCAL Series, Vol. 6, No. 1, Fedhu.^ry, 1965 23 Comments. Although this genus was estab- lished by LeConte (1851), Casey (1892, 1907) named most of the species presently therein. Comparison of our series was made with speci- mens of A. brunneus Casey. This genus is in need of revision. 9(1-1)A-11 Crt/pfoglossa vcnttcosa LeConte Figures V-F; XVI-C References. LeConte, Ann. Iac. N. York, V, 1851, p. 129. Lacordier, Gen. Col., 1859, p. 42. Horn, Trans. Amer. Phil. Sot., XIV, New Series, 1870, p. 280. Triplehorn, Coleopterist's Bull., Vol. 18, No. 2, pp. 43-52, 1964. Morphological Characteristics. Length 17 to 21 mm; form elongate-oval; veiy heavv appear- ance, light bluish-gray to deep black. Head, an- terior front coarselv punctate; coalescent; the verte.v granulate; eyes emarginate; antennae short and flattened with the eleventh segment truncate and much smaller than the tenth. Pro- notum vei"v rough and tuberculate; a medial su- ture extends from the ape.x to the base; apical angle acute and extended. Elytra evenly arcu- ate from base to apex: nine rows of large, evenly- spaced tubercles traverse the full length; apex abruptly rounded. Legs long and stout; the tarsi co\ered with reddish-orange spines. Plant Community Relationships. A total of 116 specimens was collected. The greatest num- ber occurred in the Lycium community, with about one-fourth the number in Mixed, over one-tenth in Artemisia, and slightly fewer than one-tenth in Larrea-Franseria. They were not obser\'ed in Atriplex-Kochia, Gravia-Lvcium, Salsola, Coleogvne, or Pinyon-Juniper. Seasonal Activity. This species occurred from April to September, but was most abundant in August. One specimen was collected in Novem- ber. Abundance was increased from May to June, declined slightly in July and then reached a peak in August. There was a large decline in September. In the Lycium and Mixed commun- ities beetles were active from May to September, whereas in Larrea-Franseria activity was evi- dent onh' during August and September. 9(1-1)3-12 Centrioptera muricata LeConte Figures V-A; .W-F References. LeConte, Ann. Lye. N. York, V, 1951, p. 142. Horn, Trans. Amer. Phil. Soc, XIV, New Series, 1870, p. 279. GR-LY LA-FR MIXED PI-JU (A) EUPSOPHULUS CASTANEUS ( B ) EUSATTUS DUBIUS ( C ) EUSCHIDES LUCTATUS ( D ) HELOPS ATTENUATUS ( E 1 METOPOLOBA BIFOSSICEPS z u ( F ) N0TI8IUS SUBSTRIATUS -M^ ( G ) PELECYPHORUS PANTEX I H )- STERIPHANUS LUBRICANS 31 f^ ( I ), TRIOROPHUS LAEVIS POLITUS ( J ) TROGLODERUS COSTATUS NEVADUS 135 24 9 I 34 ^.■■■■■■■■■■■■.i Figure 1\. Number of specimens by species (A-J) found in nine plant communities. Uiik;iiam Vounc L'NivtubiTY Science Bl-lletin DCC JAN FEB MAR APR MAY JUN JUL I'imirc \. N'limlKT of specimens sc;i.son;illy in Mixed, Salsola, and Coleog)ne communitiis. Morphological Characteristics. Lt'iigtli 11 to 23 mill; form t'loni^atc; l)ic)a(ll\' rounded jxjster- iorlv; \ar\ing from dull gra\' to shining black. Head dccph and sparsely punctate; antennae moderate and stout, last segment oval and only siiglith- smaller than the tenth segment. Pro- notum glabrous and shining; completely mar- gined; deeply punctate laterally; punctures be- coming verv fine medially. Elvtra elongate be- coming broadly arcuate jiosteriorly; spiculae lo- cated along the lateral edges; becoming longer toward the apex. Legs moderately long and stout. Plant Community Relationships. ,\ total of l,().5tt spccinu'ns was collected. The greatest number occurred in the I.arrea-Franseria com- munity, with about two-fifths the number in L\cium and one-fourth in C;ra\ia-Lyciuin. The Coleogyne and Mixed communities supported about one-fourteenth as many In-etles as Larrea- Franseria, whereas a few specimens were col- lected in .\triplex-Kochia anil Salsola. The\- were not found in the I'in\ ou-|uui|ier or .\rtemisia communities. DEC JAN FEB DEC JAN FEB MAR APR AUG SEP OCT Figure .\1. Ninnbir of speiimens season,ilI\ in I.,iir(M- KraiiNeria, l.vciuin, and .Mripiex-koilna com- mnnities. Figure .XII. Number of .specimens sea.sonalIy in disturbed Grayia-Lycium and Grayia-Lycium communities. Seasonal Activity. This species was active froin .April through September, and was most abundant in June. From .April to June, abun- dance of beetles increased, and from June to September, decreased. Beetles began actixits' in .April in the Larrea-Franseria, Lycium, disturbed Grayia-Lycium, Salsola and Mi.vcd communi- ties. In all these e.xcept the Salsola community, activity continued until September. In Salsola the only other month in \\hich tiiey were active was June. In the Coleog)ne community they were active from .May to .August, and in Atrip- lex-K(K'hia onh' in June. 1(1-2)A-I.3 Pelccijphonis paiilcx Casey Figures IX-G; XIII; .\.\-B References. Casey, Memoirs on the Coleop- tera, III, 1912, p. 116. Tanner and Packham, Great Basin Nat., XXII, No. 4, 1962, p. 110. Morphological Characteristics. Length 16 to 22 mm; form very ventricose; the anterior small- er than the posterior; deep black. Head not denseh- separatelv' punctate; front somewhat di- hited; last segment of antennae ver\' small and partially surrounded by the tenth segment. Pro- notum moderatcK' convex; strongly granulate medialK'; edges slighth* explanatc with the sides uiuni'iih' scalloped. Kl\tr;i greatly inflated; sur- liice gr;mulate; the outer costa strong, the in- iK"r \er\ line to subobsolete. Legs fairh long Biological Series, Vol. 6, No. 1, Febru.vry, 1965 Figure XIII. Pelecyphortis pantex Casey. and stout; the anterior tibia slightly dilated at the apex. Plant Community Relationships. A total of 228 specimens was collected. The greatest num- ber occurred in the Atriple.x-Kochia community, with slightly over one-fifth the number in Artem- isia, Grayia-Lycium and under one-fifth in Ly- cium. In Larrea-Franseria they were about one- ninth as abundant as in Atriplex-Kochia, where- as their abundance in the Salsola, Colegyne and Mixed communities was approximately one- twentieth. They were not found in Pinyon-Jun- iper. Seasonal Activity. On March 31 in the dis- turbed Grayia-Lycium seven P. pantex were col- lected. No further activity was recorded until July. Except for this collection they occurred seasonally from July to October, being most abundant in August. Very few were collected in July, December and November, whereas they were slightly over one-third as abundant in Sep- tember as in August. In the disturbed Grayia- Lycium they were active in March, July, August and September. Activity in Salsola occurred during July and August, whereas in Coleogyne they were active only in August. In the Atriplex- Kochia community they were active in August, September and November. In otlier communi- ties where this species occurred they were ac- tive only in August and September. 1(1-2)B-14 Pelecyphorus semilaevis (Horn) Figures XIV; XX-C References. Horn, Trans. Amer. Phil. Soc, XIV, New Series, 1870, p. 284. Casev, Memoirs in the Coleo., Ill, 1912, p. 182. fanner and Packham, Great Basin Nat., XXII, No. 4, 1962, p. 110. Morphological Characteristics. Length 21 to 24 mm; fonn elongate-oval; nairowing from pos- terior to anterior, black. Head coarsely and sparsely punctate; front not dilated or only slightly so; eyes large and emaiginate; third segment of antennae long; ele\enth only slightly smaller than tenth. Pronotum coarselv, sparselv, and unevenly punctate; the sides are narrowly reflexed, moderately rounded and not scalloped. Elytra elongate-oval with distinct marginal costa; tliree striiight, nearly parallel costa; the surface sliining bet\veen the suture and first costa; the remainder opaque. Legs moderately long and stout; anterior tibia expanded apically into a spine. Plant Community Relationships. A total of 31 specimens was collected. The greatest num- ber occurred in the Atriplex-Kochia and the Grayia-Lycium communities and only two-fiftlis in disturbed Grayia-Lycium. Lanea-Franseria Figure XIV. Pelecyphorus semilaevis (Horn). and Lvciiim siipportt'd about one-fourtli the population of tho Atriplex-Kochia, wliertnts the CJoli-oj^siu' and Mixed communities sup[X)rted onlv about one-eighth. They were not found in Salsola, I'iinon-Juniper or Artemisia. Seasonal Activity. P- semilacvis were col- lected only from Julv tiirough September. Thcv were most abimdant in August. In all communi- ties in which the\' were foimd they were active during this month. In Lvcium and disturbed Cravia-Lvcium thev were acti\e in July. Activity in all communities ceased in September. 1(1-2)C-15 EuschUles luctutus (Horn) Figures IX-C; XIX-J References. Horn, Trans, of the Amer. Phil. Soc., XIV, 1870, p. 286. Casey, Memoirs on the Col., HI, 1912, p. 1.S5. Morphological C^haracteristics. Length 12.5 to 17.5 mm; elongate oval; black. Head ver\' sparsely punctate; eyes large and slightly pro- truding; second .segment of antennae ver)' short. Pronotum widelv and acutely margined; spars- ely punctate medially, more coarseh' and dense- ly punctate at margins. Elvtra elongate-oval; without marginal costa or ridge; surface wetikly granulate. Legs moderate and slender. BniciiA.M VouNc University Science Bulletin Plant Community Relationships. A total of 51 specimens was c-ollected. The greatest num- ber occurred in Larrea-Franseria, with about one-seventh the number in the Coleogyne and Mixed communities. A few specimens were found in Cravia-Lvcium, .^tripIex-Kochia and Lycium, whereas none was found in Salsola, Pinyon- Juniper or .Artemisia. Seasonal Activity. This species was active from September to April. Beetles were most abundant during October, N'o\ember, Decem- ber and February. Activity was noted in disturb- eeci- mens were collected from the Lycium commun- ity in January and then from April to November. This species became active in June in Mixed, Salsola and Lturea-Franseria, and November in Mixed. Grayia-Lycium had activity from July through September, the Atriplex-Kochia in Aug- ust and September, whereas in Coleogyne com- munities there was activity only in November. 32 BldfiHAM YoLNC U.S'lVEKSI'n' SCIEN'CE BULLETIN l(l-3)C-2.3 Eleoilvs hispilahris scidptilis BlaisdHi Figures VIII-A; MX-B References. Bliiisdell, Bull. 6.3, U.S. Nat. Mtis., Mono., 19(W. p. 220. TaniuT, (iri-at Basin Nat., XXI, No. 3, 1961, p. 72. Morphological Characteristics. lA-ngth 18 to 37 mm; elongate o\ate; somewhat sliiiiing; some- what c-onN'e.\ and snleate; color black. Head wider than long; antennae long, reaching to base of pronotum; outer four segments compressed and dilated. Pronotum finely, sparsely, and even- ly punctate; apical angles acute and e\erted; basal angles obtuse. Elvtra sulcata; less than twice as long as wide; sulci have a series of evenly, closely placed, small separate punctures; costa convex, sm(K)th, and sliining, each witii a single irregular series of distantly placed punc- tures, l^egs slender, posterior femora reaching fifth segment of abdomen. Plant Community Relationships. A total of 1,385 specimens was collected. The greatest numbers occurred in the Gravia-Lycium com- munity, with three-eights of this nimiber in Salsola. In Coleogyne and .\rtemisia they were onh' one-fiftieth as abundant as in disturbed Cravia-Lycium. A few specimens were taken from Larrea-Franseria, Atriple.x-Kochia and Mi.xed communities. None was found in the Pin- von-Juniper or Lycium. Seasonal Activity. This species was active from .March to December, with the peak of abundance in March, April and .May. Tlie num- bers collected dropped off rapidly in June and reniained low from July to October. In Novem- ber only four specimens were c-ollcc-ted and in December only one. In disturbed Crayia-L\'cium, C;rayia-L\ciinTi, Salsola, Coleog\ne and Larrea- Franseria communities activity began in March. In Salsola activity was recorded until Dec-em- ber whereas the disturbed Gravia-Lycium had activity until November and Gravia-L\cium only until Ma\'. .Activity in Goleog\'ne stop[X'd in April for four months then commenced again in September and October. In Larrea-Franseria there was no activitv from the end of March imtil August, when slight activity was recorded. In -Atriplex-Kochia community this species was found active during .^pril and .\ugust, whereas Mi.xed communities had actixitv only in .August and September. l(l-3)C-24 Eleodes longipilosa Horn Figures VIIl-E; XIX-F References. Horn, Trans. Amer. Ent. Soc., XVllI, 1891, p. 42. Blaisdell, Bull. 63, U. S. Nat. Mus., Mono., 1909, pp. 212, 2.30. Tanner, Great Basin Nat., .XXl, No. 3, 1961, p. 72. Morphological C^haracteristics. Length 25 to 28 mm; elongate-oval; moderately shining; with a tail-like extension; surface sparsely covered JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC (A) NOTIBIUS SUBSTRIATUS ( e ) ( B 1 PELECYPHORUS PANTEX 153 o t C I PELECYPHORUS SEMILAEVIS ( 0 1 STERIPHANUS LUBRICANS ( E I TRICHIASIDA ACERBA _3 12 9 TRIOROPHUS LAEVIS POLITUS (G) TROGLDDERUS COSTATUS NEVAOUS Figure X.\. Numlu'r of specimens sea.son;illy collected iu ;ill the l)i()tie eoinmunifies Biological Series, Vol. 6, No. 1, February, 1965 33 with long black hairs. Head irregularly punc- tate; hairs are long and flying; antennae mod- erately long and thick; slightly dilated on the last four segments; coyered yvith rather long, stiff hairs. Pronotum widest slightly in advance of the middle; irregularly and sparsely punc- tate; long flowing hairs on tlie lateral edges. Elytra attenuated posteriorly in a tail-like ex- tension; vaguely sulcate; punctures slightly niur- icate near suture, becoming strongh' muricate laterally; both long flying luurs and short stout hairs are present. Legs moderately long and thick with long fl}'ing hairs. Plant Community Relationships. A total of eight specimens was collected in the Grayia- Lycium, Coleogyne, Salsola, and Mixed com- munities. Seasonal Activity. The three collections of this species were made in September, October and November. Tlie September collection was in Mixed, Salsola and Coleog\'ne, October in Coleogyne, and November in Grayia-Lycium. Comments. One of the eight specimens was collected in a can trap. Two others were taken by hand. Both were collected at dusk, one feed- ing on Atiiplcx confertifolia and the other emerg- ing from a rodent bunow. l(l-3)C-25 Eleodes armata LeConte Figures VI-B; XVIII-A References. LeConte, Ann. Lye. N. York, V, 185L p. 134; Arcan. Nat., 1859, p. 125; Proc. Acad. Phil., 18.58, p. 181. Horn, Trans. Amer. Phil. Soc, XIV, New Series, 1870, pp. 303, 310. Blaisdell, Bui. 63, U. S. Nat. Mus., Mono., 1909, p. 2,59. Tanner, Great Basin Nat., XXI, No 3, 1961, p. 72, Morphological Characteristics. Length vari- able 24 to 33 mm; elongate; shining. Head mod- erately convex; more or less impressed laterally; frefjuently frons broadly and transversely im- pressed with the vertex sh'ongly convex; an- tennae does not reach the base of the pronotiim. Pronotum widest in advance of middle; sparsely and evenly punctulate; apical angles finely punctate; punctures in unimpressed series. Legs moderately long; hind femur reaching the fifth abdominal segment; femora with strong teeth. Plant Community Relationships. A total of 2,878 specimens was collected. The greatest numbers occurred in the Larrea-Franseria com- munity, with about seven-tenths of this number in Grayia-Lycium and four-sevenths in Lycium. In Coleogv'ne they were about one-half as abun- dant, and one-third as abundant in Atriple.x- Kochia and Mixed communities. They were only one-tenth as abundant in Salsola, and were not found in Pi nvon- Juniper or Artemisia. Seasonal Activity. These beetles were acti\'e all \ciu- long. They were far more abundant in September than at any other time. During Nov- ember, December, January and February' small numbers were collected. In March an increase occurred and a low peak was reached in .\pril and May. In June and July the numbers collect- ed decreased again. The amount increased ab- ruptly in August and continued to increase to the high peak in September; in October collec- tions decreased more abruptly. In the disturbed Grayia-Lycium this species was acti\e in Janu- ary. In Febnuu-y they were not collected, but were from March to November. In S;dsola their activity' started in February and continued through October. In Larrea-Franseria, L)cium and Mixed communities this species' activity started in M;irch and ended in November, ex- cept in Lycium where activity' continued into December. In Atripiex-Kochia, Grayia-Lycium and Coleogyne communities they yvere active in April and continued through October, except for Coleogyne in yvhich they yvere active in November. l{l-3)C-26 Eleodes iirmutii piimihi Blaisdell Reference. Blaisdell, Trans. Am. Ento. Soc, LIX, 1933, pp. 191-210. Morphological Characteristics. Length 18.0 to 20.0 nmi; yvidth 6.0 to 8.1 mm. Color black, punctation fine and very sparse, e.xccpt on head, yvhere the punctures are large, rather closely set, and feebly muricate. Head as long as wide. Epistoma truncate, frons anterially punctate. Labrum slightly con- vex, yvith an emargination at the apex. Antennae slender, in length attaining the pronotal base, third segment four times as long as the second. Pronotum wider than long, apex truncate and eniiuginate betsveen the prominent apical angles; base slightly arcuate, angles obtuse; disk convex. Elytra subcvlindrical convex; base about ecjual to that of the pronotum; humeral angles obtuse; disk rounded from side to side; puncta- tion fine, close in strial series, interval space yvith irregular sparse punctines. Legs slender, moder- ate in length. Femoral teeth small and acute. Plant Community Relationships. A total of thirty specimens was collected in the Grayia- Lycium and Lycium communities. Bi(i(;iiAM VoLNt; UNivEHsi-n- Science Bulletin Seasonal Activity. Tliese beetles were active froi7i Jiilv until October. They were far more ahimtlant in Aiii^iist and September. A few spec- imens were taken in November. They were as- sociated with arnwta. Comments. Ptiinihi may be rather readily separated troiii (irmiita by their smaller size, ahoMt one-liaH the si/e of nrmala, the shape of the pr<)not\im; the \er\' small pimetnres on the prothorax and elytra; and the smaller legs and femoral teeth, which are acute. l(l-3)C-27 Eleodcs mecimens was collected. The largest niunbers occurred in the ColeogV'ne c-omunmity, with three-fifths of the number in the Mixed and two-fifths in Salsola. They were not found in Larrea-Franseria, Lycium, Atriple.x-Kochia, Pin- yon-Juniper or .\rtemisia. Seasonal Activity. They were active during September, October and November, with great- est abundance being in September. They were active only in September in the Salsola and Mix(>d and were active in September ;md Octo- ber in Coleogvne. In disturbed Grayia-Lycium they were active only in November. l(l-3)C-30 Eleodes tcnebwsa Horn Figure \III-F References. Horn, Trans. Amer. Phil. Soc, XIV, New Series, 1870, pp. 304, 316. Blaisdell, BiOLCXiiCAL Series, Vol. 6, No. 1, Februahy, 1965 Bull. 63, U. S. Nat. Mus., Mono., 1909, pp. 311, 326. Tanner, Great Basin Nat., XXI, No. 3, p. 73. Morphological Characteristics. Length 13 to 16.5 mm; oblong-oval; el)ixal sculpturing con- sisting of very small shining tubercles arising from a very opaque base. Head densely punc- tate laterally and on epistoma; base tiibercu- late; antennae moderate in length and sUghtly robust. Pronotum densely punctate in the center and granulate at the sides. Elytra slightly wider than pronotum, sides evenly and not strongly arcuate; densely and irregularly covered with small, rounded shining tubercles. Legs moderate, anterior tarsi dissimilar in the se.ves, middle tarsi are similar. Plant Community Relationship. A total of 16 specimens was collected. The only commun- ity in which they were found was the Pinyon- Juniper. Seasonal Activity. Members of this species were active during the month of April, and then no further activity was recorded until JuK- and August. They were equally abundant during the last t\vo months. No further activitv was found after August. 1(1-3)C-31 Eleodes hrunnipes hieuisetosa Blaisdell Figure VII-A References. Blaisdell, Ent. News, XXIX, 1918, p. 162. Tanner, Great Basin Nat., Vol. XXI, No. 3, p. 75. Morphological Characteristics. Length 12 to 13 mm; oblong-ovate; very denseh' and finely sculptured. Head tsvo-thirds as wide as the pronotum, coarsely and densely pimctate; an- tenna longer than the head and pronotum. Pro- notum one-fourth wider than long; very deeply, coarsely, and confluently punctate; feebly ar- cuate to ape.x and broadly sinuate to base. Elytra nearly a third wider than tbe base of the pronotum; abruptly and obtusely rounded behind when viewed vertically; surface densely asperate, with the summits of the granules shin- ing, each bearing a short seta. Legs moderate in length. Plant Community Relationship. A total of 10 specimens was collected. They were found only in the Pinyon-Juniper community. Seasonal Activity. This species was active only in July and August, and was equally abun- dant during these months. Comments. When Blaisdell (1918) first des- cribed E. biunnipes, he called it a variety of Eleodes pimelioides Mannerheim. Tanner ( 1961 ) raised E. bninnipes to a specific level and placed brevisetosa Blaisdell as a subspecies of that species. l(l-3)C-32 Eleodes extricnta frigida LaRivers Figures Vll-C; XVIII-E Reference. LaRivers, Journ. Ent. and Zoo., Vol. 35, No. 4, 1943, pp. 54-58. Morphological Characteristics. Length 13 to 21 mm; elongate; oblong-o\ate to ovate; spars- ely sculptured. Head deeply punctate anteriorly, becoming granulate posteriorly; antennae mod- erately long and stout, reaching to the base of the pronotum. Pronotum finely and unevenly pimctate. Elytra moderately conve.x, with the sides broadly rounded; densely sculptured \\-itli small muricate granules, shiny at their summit. Legs moderately long and slender, anterior fe- mora witli acute .spines. Plant Community Relationship. A total of 30 specimens was collected. This species was found only in the Pinyon-Juniper community. Seasonal Activity. A single specimen was taken in April. No others were found until Jidy and August when the population appeared to be ec(ual during these two months. Tliere was no activity observed after August. l(l-4).\-33 Sphaeriontls dilatata (LeConte) Reference. Casey, Proc. Wash. Acad. Sci., X, 1908, pp. 56, 59. Morphological Characteristics. Length 10 to 11 mm; elongate-oval gradually pointed behind; deep black in color. Head small; front greatly dilated and deeply emarginate at the apex; (an- tennae missing on all the specimens collected). Pronotum very sparsely and finely punctate; base bisinuate; basal angles acute and reticu- late. Elytra slightly longer than wide; very feebly subcostulate with weak muricate punctiu-es in sulca. Legs short and stout. Plans Community Relationship. A total of four specimens was collected. Tliey were found only in Lvcium. Seasonal Activity. VIembers of this species were found during Febmary, April and June. They were most abundant in June. Comments. This genus was established by LeConte (1866). Casey (1908) named most of the present species. After comparing our speci- mens with a previously identified D. knausi 36 Casey the present designation was given. Tliis genus is in need of revision. 1(1-4)8-34 Eusattus dubius LeConte Figure IX-B References. LeConte, Ann. Lvc. N. H. N. Y., V, 1851, pp. 12.5, 216. Horn, Trans. Amer. Phil. Soc., XIV, New Series, 1870, p. 294; Trans. Amer. Ent. Soc-., X, 1882, p. .305; Proc. Cal. Acad. Sci. (2), IV, 1894, p. 42.3. Casev, Proc. W;Lsh. Acad. Sci., X, 1908, pp. .56, 66. Blaisdell, Proc. Cal. Acad. Sci., XXIV, 1943, p. 192. Morphological Characteristics. Length 6 to 10 mm; glabrous with a few small hairs laterally. Head sparsely piinc-tate, densely so near the trans\'erse suture; impunctate centr;iUy; front widely dilated; antennae slender; last four seg- ments dilated; the joints loose; apical segment is subcylindrical. Pronotiim very minutely punc- tate; the sides narrowly explanate; angles both apicully and basally slightly acute; scutellum wholly obsolete. Elytra as wide as pronotum or only slightly wider; surface faintly wrinkled; punctiires fine but distinct; ape.x obtuse. Pro- stemiun has only a few short hairs; process ob- tusely rounded. Legs short and stout; anterior tibia tapering into a moderate-sized apical pro- cess. Plant Community Relationships. A total of 43 specimens was collected. The greatest num- ber occurred in the disturbed Grayia-Lycium and Larrea-Franseria and a little over one- tenth in Vli.xed. These were the only communi- ties in wliich they were found. Seasonal Activity. The species was active from Dec-ember througli June and small num- bers were collected in October. The greatest numbers were c()lkx.ted in March. Only a few were collected from December through Febru- ary. After the peak in March, the numbers collec-ted dropped off during .\pril and May and then increased again in June. From Larrea- Franseria spe<;imens were collected during Oct- ober, Janiuu^', FebniiUA', .\pri! and June. Activ- ity in disturbc-d Crayia-Lycium was more in- tense and for a shorter {x-riod. Ih-re there was activity- from March through June. From the Mixed community single specimens were taken in Miu-ch, October and December. 1( 1-4)8-35 Euxaitus agiuitus Casey Reference. Casey, Proc. Wash. Acad. Sci., X, 1908, p. 76. Morphological Characteristics. Length 9 to 12 mm; broadK rounded; \ery convex; rather BntcHAM YouNC Univehsitv Science Bulletin sliiiiing; deep black. Head finely wrinkled both ;dK)vc and below the transverse sutiu-e; finely granulate iX)steriorly; last segment of antennae obtriangular. Pronotum slightly explanate, punc- tines become less distinct dorsally; scutellum completely obsolete. Elytra as wide as the pro- thorax, piirallel, sides straight, surface feebly ru- gose with sparser muricate punctures; prostem- um sparsely punctate, under-surface quite hairy. Legs stout but moderately long; the anterior tibia extended into a long, blunt apical process. Plant Community Relationships. A total of 206 specimens was collec-ted. Tliey were most abundant in Grayia-Lycium. Tliey were sUghtly over two-fifths as abundant in Salsola, whereas a few specimens were tiiken from Mixed and Coleog\-ne communities. None was found in Artemisia. Seasonal Activity. This s[)ecies was active from MiU-ch through October, with greatest abundance in August. Only a few specimens were taken in March, .^pril. May, June and October. Activity increased abruptly during July and di- minished just as abruptly during September. .\c-tivity of this species in disturbed Grayia- Ly- cium began in NIarch and continued through October. In Salsola it did not become active until July and continued through October. It was active only in July and September in Mixed. l(l-4)C-36 Coniontis ncvadensis carsonica Casey Reference. Casey, Proc. Wash. .\cad. Sci., X, 19aS, p. 85. Moqihological Characteristics. Length 11 to 13 mm; elongate; con\ex; \eT\- dark reddish- brown to black. Head finely but strongly punc- tate; front very slightly dilatt>d; eyes emargin- ate. Pronotum almost one-half as wide as long; sides broadl\- iu-cuate; finel)' punctate, witli ex- tremeh' fine, short, light hair in each; slightly alutacix>us along suture. Legs moderately short and stoc-ky; tibiae and tarsi with hea\y spines; femora punctate. Plant Communitv Relationships. A total of 31 specimens was collected. The greatest num- bers (K-curred in the disturbed Grayia-Lycium, with two-thirds of this nimiber in Grayia-Lyciimi and Mixed comiuimities. These were the only communities in which they were found. Seasonal .\ctivity. Members of this s}>ecies occurred from March through September. They were most abundant during July, August luid September. Tliey were shghtly more abundant Biological Series, Vol. 6, No. 1, Febru.\ry, 1965 37 during March and April than they were in May and June. In disturbeil Grayia-Lycium they were active from March through August. In Grayia- Lycium their activity ^^as noted onh' in April, July and August, whereas in Mixed they were active from May through August. I(l-4)D-37 ConionteUus argutus Casey Figures V-C; XV-H Reference. Casey, Proc. Wash. Acad. Sci., X, 1908, p. 145. Morphological Characteristics. The single specimen studied was 7.5 mm in length. Oblong; rather elongate; glabrous, or appearing to be so; reddish brown to black; head very small; equal in length and width; front broadly dilated; eyes di\"ided; antennae short and rather stout. Pro- notum broadly arcuate in front; the ape.x nar- rower than the base; surface finely punctate. Elytra finely punctate, but very distinct; appear- ing to be slightly alutaceous. Legs short; yer\' stout with heavy spines. Plant Community Relationship. A total of 2 specimens was collected. They were colle-cted in the Mixed community in August. Seasonal Activity. The only collection made of this spec-ies was in August. l(l-5)A-38 Blapstinus vanchjkci Blaisdell Reference. Blaisdell, Trans. Am. Ent. Soc., LXVIII, 1942, p. 136. Morphological Characteristics. Length 5 to 6 mm; oblong; moderately convex; black; pub- escent. Head widest at the middle; densely and coarsely punctate; stiff black hairs; eyes divided, the upper jx>rtion large and round; antennae robust and short; clothed with stiff black hairs. Pronotum twice as wide as long; deeply and coarsely punctate; black hairs aris- ing in each puncture; bisinuate basally. Elytra elongate; sides parallel; broadly rounded pos- teriorly; broad striae at narrow intervals; stiff, black, decurved pubescence arising from the striae. Legs fairly stout with short spines on tibia; fourth segment of anterior tarsi very short and smaller than third; the fifth segment is long. Plant Community Relationships. A total of 35 specimens was collected. They were most abundant in Grayia-Lycium. A few specimens were found in Vlixed. They were not found in any of the other communities. Seasonal Activity. This species was active from March to October. There were two peaks of activity — one in M;irch, the other in July. In the other months only a few specimens were collected. In disturbed Grayia-Lycium their activity started in March and continued until June; then in July activity started again and lasted into September. In Grayia-Lycium their activity started in May and lasted into October. In the Mixed community they were active dur- ing June and July. l{l-5)A-39 Blapstinus pubescens LeConte Reference. LeConte, Ann. Lye. N. H. N. Y., V, 1851, p. 147. Morphological Characteristics. Lengdi of four specimens studied, 7 to 7.3 mm; elongate; deep reddish brown; short \ellowish pubescence. Head deeply and coarsely punctate with slight coalescing; yellowing hairs present around eyes and over vertex; upper portion of eves large and round; antennae fairly short and gradually diick- ened toward tip. Pronotiun broadly emarginate anteriorly and deeply bisinuate posteriorly; dens- eh' and coarsely punctate; yellowish hairs later- ally and basally; margins slightly flattened. Ely- tra elongate; broad costa covered with yellowish scale-like hairs; sulci finely punctate in series. Legs fairly short and stout. Plant Community Relationship. Only four specimens were collected. They were found near Cane Springs in a Mixed community. Seasonal Activity. The specimens were col- lected in June. Comments. Specimens of this species were compared with specimens of the Horn collection in the Academy of Natural Sciences of Phila- delphia and the U. S. National Museimi by the senior author. 1(1-5)3-40 Notibius substriatus Casey Figures IX-F; XX-A References. Casey, Ann. N. Y. Acad., V, 1890, p. 479; Ann. N. Y. Acad., VIII, 1895, p. 622. Morphological Characteristics. Length 4.5 to 5 mm; oblong; somewhat robust; fairly shiny; black with reddish legs and antennae. Head wid- est at the middle; bilobed at apex; somewhat coarsely and densely punctate, apjjearing gran- ular; eyes divided, upper lobe minute; antennae robust, much shorter than head and pronotum. Pronotum one and one-half times wider than long; evenly arcuate at the sides and fringed with 38 Bhigham Vounc Unmvehsit\- Science Bulletin stout hairs; surfat-e coiirscly, deeply and strongly punctate; laterally asperate. Elytra ;is wide ;is the pronotuin; broadly roundetl behind; both feebly impressed striae and inter\als finely punctate. Legs very stout; anterior tibia dilated; middle and hind tibia with strong short spines. Plant Clommurutv Relationships. A total of 316 specimens wiis collected. The greatest num- bers occurred in the Grayia-Lycium c-ommunit\', with about two-thirds of this number in Salsola. A few spec-imens were found in Atriple.x-Kochia, Mixed, Lycium and Larrea Franseria communi- ties. They were not found in Coleogyne or Pin- yon-Juniper. Seasonal Activity. Members of this species occurred from Nhirch through November. They were most abundant in May. There was a slight increase in the numbers collected during April, which resulted in tlie population boom in May. In June the numbers declined. The\' steadily decTCiisecl in July and August and then increased sUghtly in September. Only a few specimens were collected in October and November. Acti- vity of this species started in March in disturbed Grayia-Lycium, Grayia-Lycium, and Mixed com- munities. It continued into November in dis- turbed Grayia-Lycium, died out in October in Grayia-Lycium, whereas in Mixed they had further activity only in May, June, July and September. In Salsola they were active in July and August, whereas in Larrea-Franseria and Atriplex-Kochia they were active only in July. I(1-5)C-41 Conibiosauw elungatum (Horn) Figures V-D; XVI-A References. Horn, Trans. Amer. Phil. Soc, XIV, New Series, 1870, p. 351. Casey, Ann. N .Y. Acad., V, 1890, p. 476. Moq>hoIogical Characteristics. Length con- stant ai'ound 4 mm; elongate parallel; convex; shining; head and pronotuin retldish-brown, ely- tra black. Head wider than long; finely, rather sparsely punctate; eyes divided; superior por- tion small and linear; antennae very robust; com- pact; shorter than head and pronotum; last three segments moderately dilated. Pronotum wider than heiid; finely, sparsely punctate tow;u-ds the middle, denser and more ct>arse laterally. Elytra equal in width to the pronotum; sides nearly straight; even rows of fine punctures; the striae very feebly impresscxl; the inter\'als evenly punc- tate with esich bearing a stiff seta. Legs moder- ate, tibiae not dilatetl. Plant Community Relationships. \ total of W) sptxiinens was c-ollected. Tlie greatest num- bers ocfurred in Lycium, with one-half this number in Larrea-Franseria and about one- third in Grayia-Lycium. In Coleogyne tliis spe- cies was one-fifth as abimdiuit as in Lycium. They were one-fifth as abundant in Atriplex- Kochia and one-sixth as abundant in .Mixed, where;is there were only a few specimens col- lected in Salsola. They were not found in Pin- yon-Juniper or Artemisia. Seasonal Activity. Beetles of this species were acti\e from April through October. They were most abundant in Ma\' and July. In June, August and September slightly more than one- half as man\' specimens were collected as in May and July. Only a few specimens were taken in October. They became active in April in Ly- cium, disturbed Gravia-Lycium, Coleogyne and Mixed communities. They remained active until September in Lycium; August in distm-bed Grayia-Lycium; July and .\ugust in Coleogyne; and May, July and September in Mixed. They were active in Larrea-Franseria during May, July and September, whereas in Grayia-Lycium they were active from May through July and in Atriplex-Kochia c-ommunity in June and July. Tlie collection in Salsola was made in Oc-tober. 1 ( 1-6 )A-42 Anemia calijornica Horn Figure XV-C Reference. Horn, Trans. Amer. Phil. Soc., XIV, New Series, 1870, p. 378. Morphological Characteristics. Length 3.5 to 4 mm; short; oval; robust; deep reddish- brown; winged. Heiid broad; densely and rather coiir.sely punctate; apex deeply emarginate; sides broadly dilated; eyes deeply em;irginate; sujier- ior portion small; antennae short; robust; thicker at tip; last segniCTit longer than tenth and roundetl at tip. Pronotum ne;u-ly three times as broad as long; convex; densely and coarsely punctate; fringed with long yellowish luiirs. Ely- tra broadh' o\al, sc;u-c-el\- longer than wide; sides fringixl with long yellowish h;iirs; surface deeply and cixirsely punctate. Legs short; robust; tibiae all dilated, covered with long yellowish hairs. Plant Community Relationship. A total of 5 specimens was collected. They were found in the Lycium communit)'. Seasonal Activity. This sjjecies was collected in May and June. Comments. Beetles of this species are noc- turnal fliers. Thev were collected by their at- traction to ultra-violet light. Not enough collec- tions were made with the ultra-violet light to Biological Series, Vol. 6. No. 1, February, 1965 39 determine this s{>ecies' seasonal range of activit)' or community restrictions. Their body form re- sembles the Scarabaeidae. l(l-7)A-43 Coelocnemis punctata LeConte References. LeConte, Proc. Acad. Nat. Sci., VII, 1854, p. 22.5. Horn, Trans. Amer. Phil. Soc, XIV, New Series, 1870, p. 337. Casey, Memoirs on the Coleoptera, XI, 1924, p. 319. Morphological Characteristics. Length of specimen 20 mm; elongate; conve.\; dull black; moderately shining; resembles Eleodes. Head longer than wide; deeply, finely, and rather thickly pubescent; eyes large and reniform; an- tennae short and stout; first segment long and broad; the second segment very short; last five segments slightly compressed. Pronotum wider at ape.x than base; almost as broad as long; sur- face finely punctate. Elytra finelv punctate and finely wrinkled; posterior rather suddenly slop- ing. Legs fairly long; tibiae and tarsi with fine silken pubescence underneath. Plant Community Relationship. The single specimen collected was in Pim'on-Juniper. It was collected by hand from under rocks. Seasonal Activity. This specimen was col- lected on [uly 26. Comments. This genus needs to be com- pletely revised. l(l-7)B-44 Alaephiis nevailcnsis Tanner, New Species Figures IV-A; XV-A; XXI Form elongate, rufotestaceous, median and lateral portions of the prothorax and elytra slight- ly paler; head and prothorax densely subrugose- ly punctate, dull in contrast to the rest of the body; elytra with prominent closely set punc- tures with inconspicuous short pale setae. Head small, widest at the eyes, which is one- half as wide as the prothorax; maxillary palpi prominent, third segment hatchet-shaped. Eyes small, not noticeably projecting beyond the sides of the front; width between the e)es above, five times the length of the second joint of the an- tennae, beneath separated by four and three- tenths the length of the second antennal seg- ment; antennae slender, less than half the length of the body; third joint only a little longer than the fourth segment; tenth segment slightly long- er than the eleventh. Prothorax tAvo-thirds wider tlian long; apex four-fifths as wide as base, sides evenlv rounded. not sinuate before the hind angles, which are obtuse; disk evenly convex. Elytra four times as long and twice as wide as the prothorax; humeral angle obtuse, sides parallel and arcuate beyond the middle; punc- tures under high magnification muricate with pale short hairs, noticeable near the decUvity and margin. Scutellum prominent, wedge- shaped. Prothorax beneath rugulose punctate. Metasternum and abdomen finely, sparsely punc- tate; each puncture bearing a pale decimibent seta. Basal joint of the hind tarsus only a frac- tion longer than the distal fourth joint. Length 6.6 mm; width 3 mm. Type locality: Mercury, Nye County, Nev- ada. Collected b)' members of Brigham Young University, AEC Project, 1961-62. Type and four paratopes in entomological collection at Brigham Young Universit)'. Remarks: Nevadensis belongs in Fall's coup- let— eyes small, etc. — and is related to Horn's pallidus. It is a smaller species, darker, without the shining elytrae. Eyes are separated both Figure XXI. Alaephus nevadensis Tanner. ( 1 ) Dorsal view of female; ( 2 ) dorsal view of head showing shape and distance of separation of the eyes. Bni(;iiAM VoLNc Umvehsity Science Bulletin above and bcnt'iitli more tlian those in pallulus; antennae are shorter, the fonrtli joint is almost as long as tlie third one. Biusal joint of hind tarsae shorter than in pallulus. Plant Oommunitv Rehitionship. F"oiir speci- mens of tliis s[X,'cies were collected on July 25, 1961, on Elifintis ciiwrcux, a large-type hunch grass, in a Mixed community and one on July 1, 1961. in a Mixed community. Comments. The specimen collected on July 1 was in a Mi.xed coinmunitv near Cane Springs in tlie same can trap as Bhipsliniis puhescem. l(l-7)C-45 Eupsophidus cii.staucti.s Horn Figures IX-A; XIX-I Reference. Horn, Trans. Amer. Phil. Soc, XIV, New Series, 1870, p. 347. Morphological Characteristics. Length 9 to 14 mm; elongate; chestnut brown; moderately shining. Head elongate; front narrowing anter- iorly and broadly emarginate; ver)' sparsely punctate; eyes broad; antennae longer than the head and pronotimi; last segment long and slender. Pronotum sub(|uadrate; slightly broader than long; surface sparsely punctured. Elytra elongate-oval; broader at base than pronotum; humeri distinct; sparsely punctured. Legs slen- der; tarsi long with short spinuous hairs. Plant Community Relationships. A total of 35 specimens was collected. The greatest num- bers occurred in a Mixed cx)mmunitv', with un- der one-half this number in Lycium and one- tliird in Crayia-Lycium. In Larrea-Franseria they were one-sixth as abundant as in Lvcium. They were not present in .^tiiplex-Kochia, Salsola, C-ol- eogyne ;md Pinvon-|uniper communities. This species is a nocturnal living fonn. Most of the collections in Lvcium and Mixed were made by the beetle's being attracted to ultra-violet light. Seasonal Activity. This species was active during May, June and Julv. Comments. Due to the few specimen col- lection attempts made with ultra-violet light it is not possible to make an accurate determina- tion of .seasonal activity or relati\e abundance in the separate communities. 1(1-8) A-46 H flops attemuitiis LeConte Figiirts IX-D; XIX-K References. LeConte, Ann. Lye. N. Y., V, 1851, p. 1.37. LeConte and Horn. Class. Col. N. Amer., 1883, p. 240. Horn, Trans. Amer. Pliil. Soc, XIV, New Series, 1870, p. .397; Trans. .\mer. Ent. Soc., VIII, 1880, p. 1.52. Seidlitz, Natiirg. Ins. Deutschl., V, 1896, p. 696. Morphological Characteristics. Length 5 to 10 mm; elongate; con\ex; \;iries from reddish- brown to black with some ha\ing a lighter head and pronotum than elytra. Head fairly long; front dilated; coarse, dense punctures; eyes transN'erse and large; antennae long with outer joints siightlv compressed and pubescent. Pro- notum longer than broad; finely, densely piuic- tate. Elytra elongate-o\al; almost subcylindrical; humeri rounded; striae of coarse punctures. Legs long and fairly stout; heavy pubescent pad on all but the last segment of the tarsi. Plant Community Relationships. A total of 140 specimens was collected. Iliey were most abundant in Crayia-Lycium and about four- sevenths as abimdant in the Larrea-Franseria, Coleogyne, Salsola and .\triplex-Kochia. In Mix- ed the\' were two-sevenths as abundant as in disturbed Crayia-Lycium. They were not present in Lycium, Pinyon-Juniper, or Artemisia. Seasonal Vctivity. This species was active during even.' month except September, with the greatest numbers being collected during Febru- ary. Only a few specimens were collected in May, June, JuK-, .\ugust and October. There was an abrupt increase in the numbers «)llected during November, and then the\' remained at about the same le^•el througli December, Janu- ary, Miuch and April. In disturbed Cravia-Lv- cium and Mi.xed, activits' began in October. They remained active in disturbed Gravia-Ly- cium until June, whereas in Mixed they were active only until .March. In Crayia-Lycium, Sal- sola and Larrea-Franseria they were acti\'e through March, and in Salsola into Febniarv. In Coleog\ne the\' were active in Febniarv, March and .Vprii; whereas in .\triplex-Kochia thev were active in Februan-, .\pril. May, August and Oct- ober. Biological Series, Vol. 6, No. 1, Febhi'.\ry, 1965 DISCUSSION 41 In the desert areas of southwestern United States the darkhng beetles constitute a conspic- uous part of the ground-dwelling insects. They are primarily nocturnal and spend the day under rocks, debris, loose bark or in rodent burrows. Occasionally on cloudy days they may be seen lumbering along the desert floor. To the casual observer of such desert regions, it may seem sur- prising that 46 species of tenebrionids occur in the relatively small iu"ca comprising the Nevada Test Site. However, upon closer examination of the vegetation, it is apparent that a variety of habitats exists for which many species of beetles may be indigenous. Inasmuch as this is appar- ently one of the first studies of its kind dealing with tenebrionids of a specific area, investiga- tions in other desert areas may demonstrate these beetles to be even more common than this study has indicated. Abundance of Species At the Nevada Test Site the number of species of beetles found varied between plant communities. The Mixed and disturbed Grayia- Lycium communities supported the largest num- ber of species, whereas the fe\\'est were found in Atriple.x-Kochia and Pinvon-Juniper. These relationships may be explained on the basis of the greater variety of plant species which occur there. Such a mixture likely makes available a large variety of food for the plant-feeding dark- ling beetles. There are also a variety of micro- habitats available to the many species. Compar- ing this environment with that of the Atriplex- Kochia where relatively fev\- species were pres- ent, it is evident that in the latter community there are few plant species other than the two predominant ones. The vegetation is very short and sparse, and the number of micro-habitats is greatly reduced. These factors likely influence the number of species that may inhabit this community. The Larrea-Franseria and Lycium communities, which ;u"e typical of the Mohave Desert, supported almost as many numbers of species as the Grayia-Lycium, which is more typical of the Great Basin Desert. Other com- munities such as Atriplex-Kochia and Coleogyne supported fewer species than Larrea-Franseria and Lycium, even though they occupied the same geographic localities. Pinvon-Juniper, typ- ically Great Basin, supported the least number of species of all communities. Very likely the higher altitude, lower temperatures, increased moisture and longer periods of snow cover were limiting factors c-ompared to many species found in the other communities. This would lead one to assume tliat similar communities of the Mo- have Desert may support a greater number of species than the Great Basin communities. In areas where nuclear detonations have disturbed the normal biotic conditions, a differ- ent species association occurs. The disturbed Grayia-Lycium had a greater number of species than Grayia-Lycium whereas Salsola had less. In these areas the Salsola is just beginning the process of revegetation, and the number of in- vader plants are few. Disturbed Grayia-Lycium, however, is an ectonal area between the more stable, undisturbed plants and tliose areas where the native plants were completely eliminated. This communit)', then, may share species that are indigenous to the other two. Populations With reference to total populations of all tenebrionids, the disturbed Gra\ia-Lycium con- tained approximately one-third more individuals than Larrea-Franseria. Lycium and Coleogyne supported only one-fourtli as many specimens as did disturbed Grayia-Lycium. The Mixed community, in which the largest number of species was found, supported only one-seventh die population of disturbed Grayia-Lycium. The number of specimens in Atriplex-Kochia was considerably less than in any other community. W'ith reference to all tenebrionids there were two seasonal papulation peaks. In May and Sep- tember over 2,000 specimens were collected. Ap- proximately 1,.500 were taken in June, 1,000 in July, and 1,500 in August. From the peak in September there was a sharp decline in num- bers collected until December, when fewer than 100 individuals were found. In Coleogyne, Grayia-Lycium and Mixed communities the largest number of beetles col- lected was in September, with a lower peak in April and May (Figs. X and XII). The number collected in Larrea-Franseria, Lycium and Atriplex-Kochia increased gradually from a December low to a high in August and Septem- ber ( Fig. XI ) . Following this the number col- lected declined rapidly. High populations oc- curred in disturbed Grayia-Lycium and Salsola during March, April and May, when the num- bers of specimens taken were over a thousand each month. Collections declined in the follow- ing months, with a small increase in August and September (Figs. X and XII). 42 BitiGiiAM YoLNC UsivEHsm- Science Bulletin Plant Community Relationships Certain species demonstrated apparent plant communitv assoc-iatioii more tlian others. These associations were shouni bv Allred, ct al. ( 196.3a, pp. 42-43). One species, Eleodes obscura sulcipennis, was present in every community at the test site, whereas others were variously distributed in their occ-urrence. Si.\ species, E. extricata jri'^ida, E. tenebrosa, E. bmnnipes brevisctosa, E. nieniated ". . . in the adult or partly grown larval stage." O'Kane ( 1924 ) states that some tenebrionids have one generation annual!)'. As shoun by this study there iire t\vo population pe;ilcs — May and Sep- tember. These two peaks suggest that some species metamorphose from pupa to adult in the autumn and over-winter as adults. Others o%'er- winter as larxae and emerge as adults in the spring. This may account for the two seasonal peaks in May and September and low numbers during July and the winter months. iiOLOciCAL Sehies, Vol. 6, No. i, February, 1965 SUMMARY The intent of this study conducted over a period of three years was to ( 1 ) provide des- criptions of the species of tenebrionids found at the Nevada Test Site, (2) determine their rela- tive abundance, (3) determine their seasonal activity, and (4) ascertain their plant commun- ity relationships. A total of 14,650 beedes representing 46 kinds of tenebrionids was collected with sun- ken can traps, by hand, and ultra-violet hght. Collections were made at regular intervals in the following plant communities: Larrea-Fran- seria, Lycium, Atriplex-Kocliia, Grayia-Lycium (disturbed and undisturbed areas), Salsola, Coleogyne, Pinyon-Juniper, and Mixed. The data obtained from this studv indicate that ( 1 ) more species were present in some plant communities than in others; (2) in nuc- lear disturbed areas a larger number of species was present than in undisturbed areas; (3) some species were more closely associated with some plant associations than with others; (4) those species that were not widely distributed ecol- ogically were fewer in number of indi\dduals, whereas those that were widespread occurred in larger numbers, relatively speaking; ( 5 ) the spe- cies demonstrated variation in seasonal activity in that some were active for short periods where- as others were active during the whole vear; and (6) the two seasonal peaks in population are indicative that some species over-winter as adults whereas others over-winter as larvae. LITERATURE CITED Allred, D. M., D E.Beck, and C. D.Jorgensen. 1963a. Biotic Communities of the Nevada Test Site. Brig- ham Young Univ. Sci. Bull., Biol. Ser., Vol. 2, No. 2, 1963b. Nevada Test Site Study Areas and Specimen Depositories. Brigham Young Univ. Sci. Bull., Biol. Ser., Vol. 2, No. 4. Amett, Ross H. 1960-1962. The Beetles of the Unit- ed States, pp. 1-1111, Tcnebrionidae. pp. 645-696. Catholic University of America Press. Blackwclder, R. E. 1939. Fourth Supplement, 1933 to 1938 ( inclusive ) , to Leng's Catalogue of Cole- optera of America, North of Mexico. Mount Ver- non, N. Y.: John D. Sherman, pp. 1-146, Blackwelder, R. E., and Ruth M. 1948. Fifth Sup- plement, 1939-1947 (inclusive), to Leng's Cata- logue of Coleoptera of America, North of Mexico. Mount Vernon, N. Y.: John D. Sherm - Nh- r^»«j > ^.'-^ vip. Z0( LIBRARY ,V!AY6 1965 ^ A.V UNIVERSITY BRIGHAM YOUNG UNIVERSITY SCIENCE BULLETIN OBSERVATIONS ON THE BIOLOGY, ANATOMY, AND MORPHOLOGY OF OTOB/US LAGOPHILUS COOLEY AND KOHLS by C. Selby Herrin and D Eldlen Beck Biological Series — Vol. VI, No. 2 FEBRUARY 1965 BRIGHAM YOUNG UNIVERSITY SCIENCE BULLETIN OBSERVATIONS ON THE BIOLOGY, ANATOMY, AND MORPHOLOGY OF Or08/US LAGOPHILUS COOLEY AND KOHLS by C. Selby Herrin and D Elden Beck Biological Series — Volume VI, Number 2 FEBRUARY 1965 MUS. COMP. ZOOL UNIVERSITY. TABLE OF CONTENTS Page INTRODUCTION AND REVIEW OF THE LITERATURE I MATERIALS AND METHODS 2 GEOGRAPHIC DISTRIBUTION 3 SEASONAL OCCURRENCE 3 HOST-PARASITE RELATIONSHIP 3 LIFE HISTORY 7 DISEASE TRANSMISSION POTENTIAL 8 ANATOMICAL AND MORPHOLOGICAL OBSERVATIONS 9 Distinctive Generic Characters of Otobius 9 Adult Characters of O. lagophilus 9 Nympha] Characters of O. lagophilus II Larval Characters of O. lagophilus 12 TAXONOMIC KEYS 16 Pictorial Key for Separation of Adults 16 Pictorial Key for Separation of Nymphs 16 Pictorial Key for Separation of Larvae 17 SUMMARY 18 ACKNOWLEDGMENTS 18 REFERENCES 18 LIST OF TABLES Table I. Collection records of Otobius lagophilus 4 LIST OF FIGURES Fig. 1. Seasonal occurrence of O. lagophilus 3 Fig. 2. Geographic distrilnition of O. lagophilus 6 Fig. 3. Host preference of O. lagojihilus 7 Fig, 4. Dorsal view of adult female O. lagophilus 9 Fig. 5. Ventral view of adult female O. lagophilus 10 Fig. 6. Dorsal view of adult male O. kigophilus 10 Fig. 7. Ventral view of adult male O. lagophilus 10 Fig. 8. Legs I and IV of adult O. lagophilus 10 Fig. 9. Ventral view of capitulum of adult O. lagophilus 10 Fig. 10. Dorsal view of nymphal O. lagophilus II Fig. 11. Ventral view of nymphal O. lagophilus 11 Fig. 12. Dorsal view of unengorged nvmphal O. lagophilus , 11 Fig. 13. Dorsal view of fully engorged nymphal O. lagophilus 12 Fig. 14. Ventral view of capitulum of nymphal O. lagophilus 12 Fig. 15. Dorsal view of larval O. lagophilus 13 Fig, 16. Ventral view of larval O lagophilus 14 Fig. 17, Dorsal view of unengorged lar\'al O. kigophilus 15 Fig. 18. Ventral view of unengorged larval O. lagophilus 15 Fig. 19. Dorsal view of fully engorged larval O. lagophilus 15 Fig. 20. Ventral view of fully engorged larval O. lagophilus 15 Fig. 21. Dorsal pits of adult O. megnini 16 Fig. 22. Dorsal pits of adult O. lagophilus 16 Fig. 23. Anterodorsal view of spines of nymphal O. megnini 16 Fig. 24. Posterodorsal view of .spines of nymphal O. megnini 16 Fig. 25. Ventral view of capitulum of nymphal O. megnini 16 Fig. 26. Dorsal view of right side of nymphal O. jyiegnini 16 Fig. 27. Anterodorsal view of spines of nymphal O. lagophilus 17 Fig. 28. Posterodorsal view of spines of nymphal O. lagophilus 17 Fig. 29. Ventral view of capitulum of nymphal O. lagophilus 17 Fig. 30. Dorsal view of right side of nymphal O. lagophilus 17 Fig. 31. Dorsal view of larval O. megnini 17 Fig. 32. Dorsal view of larval O. lagophilus 17 OBSERVATIONS ON THE BIOLOGY, ANATOMY, AND MORPHOLOGY OF OTOBIUS LAGOPHILUS' by C. Selby Herrin- and D Elden Beck^ INTRODUCTION AND REVIEW OF THE LITERATURE The principal objective of this study is to bring up to date information on geographic dis- tribution, seasonal occurrence, and host-parasite relationship of the soft-bodied tick Otohius lagophilus Cooley and Kohls in western North America. Notes on life history and disease trans- mission potential are also added. Drawings and descriptions of some external anatomical and morphological features in the adult, nymphal, and larval stages are given to assist in tlie identi- fication of individual organisms. A pictorial key is included to facilitate the identification and separation of the two species, O. lagophilus and O. megnini Duges. The spinose ear tick was described by Duges (1884) as Argas megnini. It was latei- removed from Argas and placed in the genus Ornithodoros by Neumann (1896). Banks (1912) separated it from Ornithodoros aiid pro- posed the new genus Otohius, with O. megnini as the tvpe. In 1940 Cooley and Kohls described the second species of the genus, O. lagophilus. Previous to 1940 there were several reports of collections of rabbit ticks identified as Ornitho- doros megnini ( Hadwen, 1913; Cooley, 1932). These were later shown to be O. lagophilus. The first detailed study of the genus was made by Cooley and Kohls in 1944. In their paper describing the adults and nymphs of O. lagophilus, Cooley and Kohls (1940) included three photographs of whole ticks and several drawings of niouthparts, spines, and legs. The morphological and anatomical differences between O. megnini and O. lago- philus were noted, and all available collection records were reported. Later Coolev and Kohls (1944) published this same material with a key for the separation of nymphs and adults of the two species, and brought collection records up to date. The earliest recorded collections of O. lag- ophilus were from Lethbridge, Alberta, Canada, in 1912 ( Hadwen, 1913 ) and Powder^■ille, Mon- tana, in 1916 (Cooley, 1932). Additional collec- tions were later made in tlie same area of Can- ada (Coolev and Kohls, 1944). The species is now known from Montana (Cooley and Kohls, 1944), Wyoming (Cooley and Kohls, 1940, 1944), Colorado^ (Coolev and Kohls, 1944), Utah (Beck, 1955; Hopla, 1955; Rosasco, 1957; Bacha, 1957), Nevada (Cooley and Kolils, 1940, 1944; Philip, Bell, and Larson, 1955; Beck, Allred, and Brinton, 1963), California (Cooley and Kohls, 1940; Loomis, 1953; Ryckman, Lindt, Spencer, and Lee, 1955), and Mexico (Silva- Goytia and Elizondo, 1952b). Additional re- cords from Nevada and Utah iirc included in this paper. Important studies on life history have been made by Hopla (1955) and Bacha (1957). Some notes have been published bv Woodbury (1955), Loomis (1961), and Rees'(1962). The first evidence of O. lagophilus as a potential vector of disease was given by Silva- Goytia and Elizondo ( 1952b ) in dieir work on Rockv Mountain spotted fever in Mexico. A short time later Philip, et. al. (1955) reported finding rickettsiae related to Rocky Mountain spotted fever and Colorado tick fever virus in O. lagophilus in Nevada. Eklund, Kohls, and Brennan ( 1955 ) isolated tlie Colorado tick fever \irus once from O. lagophilus collected in north- ern Nevada and in northern Utah. The only other implication of this species as a potential disease vector was by the workers in the Uni- 'This investigation was supported (in part) by Research Grant AI-01273-07 from the National Institutes of Health, U.S. PuWic Health Service. "Department of Zoology and Entomology, Brighani Young Universit)', Provo, Utah. 1 BuiciiAM VoLsc Un'isehsitv Science Bulletin versity of Utah Kt-ological and Epizoologic;il Research Unit at Diigwav, Utali, in which they demonstrated hv laboratory experiini'nts the capabihty of this tick as a reservoir and agent of transfer of tularemia (Vest, 1957, 1959, 1960; Rees. 1962). Since the original description by Cooley and Koiiis (1940) little work has been done on the anatomy and morpholog}' of this tick. Cooley and Kohls (1914) listetl some features in their ki'y for the separation of nsinphs and adults of (). l(i<^()philu.s and O. vu'<:,nini. Bacha (1957) made some notes on this subject in c-onnection \\ith life hisf()r\' studies. MATERIALS AND .METIKJDS Rabbit hosts were collected afield by shoot- ing them. Kach dead rabbit was placed in a paj>er bag and returned to the iaborator\- wiiere it was carefulh' examinetl in a large, white enamel pan under incandescent illumination. The warmth prtnided bv the lamp stimulated tick movement. Most larval and nvmphal ticks were removed bv c-ombing the hair about the face near the vibrissac and eyes, and on the ears and neck. The adults are nonparasitic and field collections were specimens which \\ere found on the ground. Specimens of all stages of development were preserved in 7(Ki' ethvl alcohol contained in two-dram shell vials. An identification tag with field number, place, host, and name of collector was placed in each vial. Tlie field num- ber was rec-orded in a field n()teber ruled 4 s<]uares to the inch. This sketch was then transferred, with the U!>e of tracing pajier, to mitlium weight, cold press- ed surface illustration board. Details of anatomi- cal and morphological structure were adde t~ -H 05 00 00 < ■q- CI t^ C t- !_ OI Ol IM — Ol -^ 10 i^ o i/> i;c i/^ X as *" -? -^ "^ -? -■ H H H "J. H H '^. .a. D b D D D D sc S S S S S S S S S S S S ^ •'^ '".'"! 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U U -S .2 4J rt .2 4^^ >.§Sg^E ffl £ "*^ ^ ^ " >^> . , iT Z c/5 Z j; f2 :£ S 1 .-■ ._; .„• U .^ 1'^ I S S E j: 6 o n niOfMro iin 03 J J — • iM CO CO] Z2ZZZ2ZZZZZZZO DDDDDDDD W) M 60 BC bC bO M c c c c c c g S E S E S E 'E ^j::Xj=j= — — -c— c c o o o o o I I o C ■ - 2 o "K t3 N -a c o Z „ >^B Q O CS '2 .3 M § . 3 ■a; ^-s bO a S3 •J . BiiuaiAM VouNG Univebsitv Science Bullettin T7^ ^ Fig. 2- Gcograpliie ilislrilmtion of O. /(/^'o/i/ii/i/.v Coolcxj and KohLi Biological Series, Vol. 6, No. 2, February, 1965 the region of Montana, Wyoming, and southern Canada the tick has been collected primarily from the white-tailed jack rabbit, L. toicnsendii. A few collections from three species of Sylvilagtts of western North America have been made throughout the known range of this tick. Loomis (1953) reported finding adults, nymphs, and larvae at the entrance to an active rodent burrow. He stated that many small rod- ents may play a more significant role as hosts than has been susjjected, although he did not name species. Observations on the use of laboratory animals as suitable hosts for O. lagophilus were reported bv Bacha (1957). He stated that although the prefened laboratory host is L. californicus, larvae occasionallv attach to the cottontail rabbit, Si/lvihigu.s aiidiibonii, and the domestic white rabbit, Ori/ctolagufi cuniculu.s. His attempts to infest an adult kangaroo rat {Dipodomijs ordii), a suckling deer mouse {Peromyscus manicidattis), and a suckling west- em harvest mouse (Reithrodontomys megcdotis) were unsuccessful. Attempts to use guinea pigs as laboratory hosts have been unsatisfactory even though in several cases larvae attached to test pigs (Hopla, 1955; Bacha, 1957). An index of host preference for O. lag- ophilus is shown in Figure 3. This was deter- mined bv counting the number of times the parasite was collected from a given host, rather than the number of specimens found on the host. Fig. 3. Host preference of O. lagophilus, expressed as number of collections per host. A-Lepus cali- fornicus. B-L. toiLiificndii. C-L. species( un- identified). D-Sylvilag'is species (S. audubonii, S. nuttcillii, and S. idahoensis). E-on ground or in rodent burrows. F-all others ( Eqtius asiuus, Felis cattis, and several not known ) . LIFE HISTORY Little is known about the life history of O. lagophilus in nature, and only few laboratory studies have been made ( Hopla, 1955; Bacha, 1957). After emergence from the egg, the larva crawls about and seeks a suitable host or clings to low vegetation to await a passing host. It attaches to the host and feeds until fully engorg- ed, then molts and transforms to a nymph while remaining attached to the same host. The nymph does not detach and drop from the host until it has completely engorged (Woodbury, 1955; Bacha, 1957). Bacha ( 1957 ) observed that after the larva attaches to the host, appro.ximately 14 to 17 days are re(|uired before it molts to a nymph. The period from the larval molt to the nymphal molt averages about 41 davs ( Hopla, 1955; Bacha, 1957). Adult O. lagophilus lack functional mouth- parts, are not parasitic, and thus do not feed. During the nvmphal stage sufficient food is obtained for completion of the life cycle. After the nymphs drop from the host and molt to adidts, the males and females seek each other and copulation takes place. In Bacha's experi- ments 6 to 29 days (average 14.6) ensued after copulation before ovi{X)sition. Hopla reported 67 days. Bacha stated that copulation of adults was essential to the production of fertile eggs but not nec-essaiy for oviposition. Hopla found oviposition to be of the inter- mittent, interrupted type. In his observations all females deposited three different egg masses, except one which deposited four. Oviposition of each egg mass required about 10 days for 100 to 250 eggs per mass. He reported that by the time the larvae from one egg mass were emerg- ing, the female was laying again. Bacha did not state whether oviposition in his experiments was of the intermittent, interrupted type, but in general his obsei"vations agree with Hopla's. The average incubation time was reported to be 15 to 18 days (Hopla, 1955; Bacha, 1957). Bitir.iiAM VouNc University Science Bulletin DISEASE TRANSMISSION POTENTIAL Silva-Ciovtia and Eli/ondo (1952b) report- ed tlu- lirsf f\idfiice fliat O. hi'^ophilus iniglit be a vector of disease. Tlieir studies were con- cerned \s ith American spotted fe\er ( Rocky Mountain spotted fe^er) in uliat is termed the ■Region of tlie Laguna" winch is composed of tlie state of Coaliuila and Durango. Mexico. Thev carried out epidcniiological studii'S tliroughout this region on domestic animals and humans. In tiu' area where spotted fever was endemic, the\- found about 7-3'f of the domestic animals to be positive for complement- fi.xing antibodies against the rickettsial antigen. In their studies on lium.ms they found 30!< of the population in these endemic areas to have com- plement-fixing antibodies. In addition they were able to isolate the spotted fever rickcttsiae from the blood of about 15 patients suffering from the disease. Tlie organisms were isolated in developing chick embrjos 5 days old. The ricket- tsiae were classified as Dcrmnccntroxenus licket- tsi rickcUsi {= Rickettsia rickcitsii). The isolat- ed strains were identical to those of the Rocky Mountain spotted fe\er of tile Bitterroot Valley in Montana. In attempting to disioNcr tlic vectors of the disease, Silva-Oovtia and Eli/.ondo collected 83 lots of ectoparasites, including soft-bodied ticks of several species. Each lot was divided into two parts; one was used for guinea pig inoculations and the other for the inoculation of 6-da\' old fertile chicken eggs. Three strains of spotted fe\er rickettsiae were isolated from the guinea pig inoculations, the fertile egg in- oculations all giving negative results. Comple- ment-fixing antibodies against the rickettsiae were found in the surviving guinea pigs of the inoculations vielcling the isolated strains. These three strains were isolated from Oinifhodoros niralici, Otohitis l(iefed for life, but is not capable of transmitting the organisms to its voung. JioLOGiCAL Series, \^ol. 6, No. 2, February, 1965 Vest ( 1961 ) reported that over a period of three vears 287 O. lugophilus ticks were tested for Q fever. None were found to be infected. An experiment was conducted to determine the capabiHty of this tick to function as a reservoir and agent of transfer of Q fever. Due to teclini- cal difficulties no data were obtained (Vest, 1960). Since O. Icigophilus is a one-host tick, re- maining attached to the same host during the larval and nymphal stages, there is little chance of its being an important vector of any disease in nature. The possibility of transovarian trans- mission of disease organisms has not vet been demonstrated. This tick may be a potential re- servoir of diseases in nature if an animal eats an infected tick. ANATOMICAL AND MORPHOLOGICAL OBSERVATIONS Distinctive Generic Characters of Oto- biiis. Adults and nymphs of the genus Ofobius are distinguished from other soft-bodied ticks by the panduriform shape of the body. Tliere is no change in the te.xture of the integument at the sides of the body, and the body margin is rounded. Hood and eyes are absent except in larval O. megnini, which has two pairs of eyes. The sexes are similar, although females lu'e generally somewhat larger than males. Anatomical and moq:)hologieal features are distinctive for each stage in the life cycle. The integument of the adult is granulated, and the capitulum is distant from the anterior margin. The hypostome is vestigial and without denticles. The integument of the nymph is striated and spinose, and the capitulimi is near the anterior margin. The hypostome is v\'ell developed with denticles. Tlie body of the larva is oval, and the integument thin and striated. On the dorsal body surface is a dorsal plate which tapers slightly posteriorly. There are seven to ten pairs of dorsal setae usually divided into six or seven dorsolateral pairs and two or three centrally placed pairs. The ventral body surface has five pairs of setae. The hypostome is long, blunt anteriorly, and well developed with denticles tliroughout its entire length and in a 2/2 ar- rangement (Cooley and Kohls, 1944; Clifford, Kohls, and Sonenshine, 1964). Adult Characters of O. lagophihis. See Figures 4, 5, 6, and 7 for illustrations of dorsal and ventral views of male and female O. lag- ophilus. The illustrations are drawn to die same scale so that accurate comparisons may be made between the male and the female, and betu'een adults and nymphs. Most of the characters de- scribed may be seen in these illustrations. For those characters not shown, reference will be made to more detailed illustrations. Most of the following descriptions are taken from Cooley and Kohls (1940). The body of adults is not as definitely pandurifonn as in O. megnini. It is rounded on both ends, a little constricted just behind legs IV, and widest at legs II and III. Tlie female is generally somewhat larger than the male (Figures 4' and 6). Cooley and Kohls (1940) and Bacha ( 1957 ) made comparative measure- ments of adults and nvmphs in order to deter- mine comparative sizes at these t\\'o develop- mental stages. The respective papers may be referred to for this detailed information. The integument is granular, with numerous circular pits on both the dorsal and ventral sur- faces (Figures 4 and 5). Each pit has a single, small, central elevation with a very short fine hair on each (Figure 22). These pits are much more pronoimced dorsallv than ventrally. Dor- sally and ventrally there is a symmetrical ar- rangement of integimiental depressions, the Fig. 4. Dorsal view of adult female O. lagophilus. 10 Bkiciiam VoL'Nt: Univehsity Science Bulxetin Fig. 5. Ventral view of adult female O. lagophilus. flcK>rs of which are irregular, being more ac- centuated in tlie male tlian female ( Figures 4, 5, 6, and 7. The legs are short and moderately heavy, with few setae. On each tarsus is a moderate siibapical dorsal protuberance which is most pronoimced (m tarsus IV (Figure 8). Co.xal and supraco.xal folds are present, but less obvious in well engorged specimens. Tile basis capituli is very broad, short, cur- ved, approaching a reniform shape with a con- Fig. 7. Ventral view of adult male O. lagophilus. vex posterior border ( Figure 9 ) . The surface of the capitulum is irregular .V^entrally on the capi- tulum are a pair of posthvpostomal setae, two pairs of postpalpal setae, and fi\'e pairs of post- eromarginal setae. The palps are motlerately heav\' with article I a little more swollen than the others. Tlie palpal setae are delicate and Fig. 6. Dorsal view of .ulull m.ilc O. lugnphiliis. Fig. 8. Legs I and IV of adult O. lagoi>hilus (from Coolev and Kohls, 1940). CHELICERA HYPOSTOME PALP ARTICLE I POSTHYPOSTOMAL SETA POSTPALPAL SETAE BASIS CAPITULI POSTEROLATERAL CAPITULAR SETAE Fig. 9. Ventral view of capitulum of adult O. lag- ophilus. Biological Sebies, Vol. 6, \o. 2, February, 1965 n long. Tlie \estigial hvpostome is bluntly rounded or bilobed and without denticles. Other important characters are a pair of ovate spiracles with convex surfaces, located a little dorsal and posterior to the fourth pair of legs; a ventrally placed genital aperture in line with the posterior ends of co.xae I; a small near- ly circular anus in a postero ventral jX)sition; a short transverse postanal groove; and a faint median postanal groove. Nymphal Characters of O. lagcrphilus. See Figure.s 10 and 11 for illustrations of dorsal and ventral views of the average size nymph. Figure 12 shows an unengorged nymph and Figure 13 a fully engorged specimen. All illus- trations of nvmphs are drawn to the same scale as the adults. It should be noted that the spines are present over the entire surface of tlie body and not just around the lateral margins as is shown in the illustrations. The integument, dorsal and ventral, is smooth and shiny with fine reticulations, trans- verse striae, and spines. Spines are abundant and long at the anterior end, b€x;oming smaller and sparse toward the p)osterior end ( Figures 27 and 28). They are absent in the area surround- ing the mouthparts and are more sparse on the ventral surface than on the dorsal. In our studies we observed some variation in the size and abundance of spines in different specimens; some specimens had a rather sparse distribution of small spines, whereas other specimens had Fig. 11. Ventral view of nymphal O. lagophilus. Spines are present over entire body surface and not just around margins as shown. many large spines over most of the body. The integumental depressions so obvious in the adults are also evident in the nymphal stage, but the symmetrical arrangement is not as apparent. The legs are short and moderately heavy, with a few setae. A subapical, dorsal protviber- ance is distinct on tarsus IV as in the adult, but is absent or small on tarsi I, II, and III (See Figure 8). The co.xae are present as incon- spicuous sclerites. Coxal and supracoxal folds are faint or absent. The capitulum is somewhat broader than long and is located in a depression formed by a circular tumescence around it (Figures 11 and 14). Located ventrally on the basis capituli are a pair of posthypostomal setae, a pair of post- Fig. 10. Dorsal view of nymphal O. lagophilus. Spines are present over entire surface of body and not just around margins as shown. Fig. 12. Dorsal view of unengorged nymphal O. lag- ophilus. Spines are present over entire body surface and not just around margins as shown. 12 Bricham Young Universitt Science Bt'LLEXtN Fig. 13. Dorsal view of fully engorged nymphal O. lag- ophilus. Spines are present over entire body surface and not just around margins as shosvn. palpal setae, and three pairs of posterior central capitular setae. The palpi are moderately heavy with article I lacking a ventral swelling. Palpal setae are small and few in number. The hjpo- stome is large, w ith the sides nciuh' parallel. The denticles are long and sharp and in a 3/3 ar- rangement. Other features are a pair of circular, mildlx convex spiracles in the same position as in adults (Figure 30), and a postero\cntrally placed anus. The anus has no true grooves around it, but pre- anal and median postanal grooves are indicated CHELICERAL DIGIT CHELICERAL SHEATH HYPOSTOME DENTICLE FILE I DENTICLE FILE 2 DENTICLE FILE 3 PALPUS POSTHYPOSTOMAL SETA POSTPALPAL SETA BASIS CAPITULI POSTEROCENTRAL CAPITULAR SETAE Fig. 14. Ventr.il view of capittiluin nt ii\ iii|ili.il O. la;: ophilus. by shallow, elongated depressions. A genital aperture is not present in tlic nymph. Larval Characters of O. lagophilus. The following description of the laiva is suggest- ed by the studies being conducted b)' Clifford, Kohls and Sonenshine (Clifford, Kohls, and Sonenshine, 1964; Kohls, Sonenshine, and Clif- ford, in press). See Figures 15 and 16 for label- ed illustrations of dorsal and \entral views of laboratory reared, unengorged Iar\ac. Figures 17 and IS showing dorsal and \entral views of unengorged lar\'ae are drawn to the same scale as Figiues 19 and 20, whicli are dorsal and ven- tral views of fully engorged specimens. These illustrations give a comparison of tlie size of unengorged with fully engorged specimens. However, these are not draw n to the same scale as iue the adult and nymphal illustrations. The integument, dorsal and \entral, is thin and striated. The dorsal plate is slightly wider anteriorly than posteriorly. Seven to nine pairs of dorsal setae are present, with fi\e or si.x pairs located dorsolateral!)- and two pairs placed centrally. In all the specimens examined there were seven pairs of dorsal setae, five pairs located dorsolaterally and two piiirs centrally. Fi\e pairs of setae are present on the ventral body surface — three pairs of sternal setae locat€>d in the area between coxae II and III, one pair of anal setae within the confines of the anal circle, and a pair of postanal setae. In fiftv specimens examined the postanal setae are absent in a majority of cases, whereas in other specimens onlv one or the other of the pair is present. The other four pairs of setae are present. The three pairs of legs are long and slender, with two to eighteen setae on each segment. The coxae are not contiguous. There is a ven- trally apical spur on each coxa. Pretiu-si are long and slender. The legs of engorged larvae are often distorted and apparently functionless. The capitulum is long and slender. The Inpostome makes up a little ONer half tlie length of tlie capitulum, and the hypostome arises directly from the basis capituli and not from a median extension. On the \eutral siuface of the basis capituli are two pairs of posthypostomal setae — one pair just anterior to the point of attachment of the palps and another slightly largiM- pair ix>sterior to tiie point of attachment of the palps. Tlie palps are long and slender, each article possessing from none to nine setae. The Inpostome is long, with large, sharp denti- cles in a 2 2 anani^i'iiUMit. ■Spir.ulfs .uul a gcnit.il (i[)ening are absent, but there is a postcrior-\ entrally placed anus. JiOLOGiCAL Series, Vol. 6, No. 2, Febru.\rv, 1965 13 CHELICERAL DIGIT HYPOSTOME PALPUS BASIS CAPITULI MARGINAL DORSAL SETA I MARGINAL DORSAL SETA 2 MARGINAL DORSAL SETA 3 DORSAL PLATE CENTRAL DORSAL SETA I MARGINAL DORSAL SETA 4 SENSILLA CENTRAL DORSAL SETA 2 MARGINAL DORSAL SETA 5 Fig. 15. Dorsal view of larval O. Uigophilus. 14 Bricham Vounc; L'NivKRsi-n Science Bulletin DENTICLE FILE I DENTICLE FILE 2 POSTHYPOSTOMAL SETA I POSTHYPOSTOMAL SETA 2 STERNAL SETA I STERNAL SETA 2 STERNAL SETA 3 ANAL SETA POSTANAL SETA Fig. 16. Ventral view of lanal O. lagophilus. Biological Series, Vol. 6, No. 2, Februahy, 1965 15 Fig. 17. Dorsal view of unengorged larval O. lagophilus. Fig. 18. Ventral view of unengorged larval O. lag- ophitus. Fig. 19. Dorsal view of fully engorged larval O. lag- Fig. 20. Ventral view of fully engorged larval O. lag- ophilus showing position of body setae (refer ophilus showing position of body setae (refer to Fig. 15). to Fig. 16). 16 liuioiiAM VoL'NC University Science Bulletin TAXONOMIC Kt:YS O. Uigophilm is easily separated from O. Cooley and Kohls (1944), and the key to the megnini by the following pictorial key. The lar\ae has been prepared with assistance from kev to adults and nviiiphs is taken largely from (Hen M. Kohls. Pictorial Key for Separation of Adults Dorsal pits separated by a distance of twice or Dorsal pits separated by a distance of the dia- more the diameter of one pit (Figure 21) . . meter or less of one pit (Figure 22) O. megnini O. lagophilus • « 6 • « tf C • t PC® B ' t 6 0 * • * C C 0 C 6 ^ 0 Q ^ C 0 c , c * « <^ <^ ' 0 • ^ e ^ c « c <^ '^ c ^ c « « . ^ ^ « " « « 0 « "ft' • e « I 6«C C 0 0 0 *■'(? ^<,6 (> ^S Q Q (i Q qQ n* 0 Oft («\c c« C 0 © 6 Fig. 21 Fig. 22 PicroRiAL Key' for Separation of Nymphs ItLfil Anterodorsal integumental spines peg-like, two or three times as thick as the more slender posterodorsal spines, and about as numerous (Figures 2.3 and 24); denticles near base of hyi^ostome in 4/4 arrangement (Figure 25); ape.x angle of spiracles about equal to or less than the basal angles (Figure 26) O. megnini Ui^ Fig. 24 Fig. 2.5 Fig. 26 Biological Series, Vol. 6, No. 2, Fei3ru.\ry, 1965 17 Anterodorsal integumental spines only slightly thicker than the posterodoisal spines, but more dense in number ( Figures 27 and 28 ) ; denticles near base of hypostome in 3/3 ar- rangement (Figiu-e 29); ape.x angle of spir- acles greater than the basal angles (Figure 30) O. lagophilus ?n »f , f r fi' » f ' '*f t ! t r ' J ' f » f I T . 1 „ ' f tf'.^ Fig. 27 Fig. 29 Fig. 30 Pictorial Key for Separation of Larvae Two pairs of eyes present; 9 or 10 pairs of dorsal Eyes absent; 7 to 9 pairs of dorsal setae ( Figure setae (Figure 31) O. megnini 32) O. lagophilus Fig. 31 Fig. 32 18 UiiK^iiAM VoLNc University' Science Bulletin SUMMARY The principal objective of this study is to bring up to date information on geographic dis- tribution, seasonal occurrence, and host-parasite relationship of O. lagopliilus in western North Americii. Notes on life history and disease trans- mission potential are included. Data and information were obtained from three sources: ( 1 ) natural history collections and field records at Brigham Young University' over the past twenty years; (2) the Rock\' Mountain Laboratory in Hamilton, Nhmtana; and (3) publisiied literature. All available collection records are present- ed in a table from which infonnation on geo- graphic distribution, seasonal occurrence, and host-parasite relationship was extracted. O. lag- uphilus is known primarily from the arid and semiarid desert regions of western North America. To a marked e.xtent the known dis- tribution of this tick follows a pattern similar to that of the black-tiiiled jack rabbit, Leptis cali- fornicus descrticola, whose distribution is soutli- ern Idalio, most of Nevada, all of Utah e.'^cept the eastern parts, wi'stern Arizona, ;ind the southeastern part of California. The preferred host of O. Icifiophiltis is L. caUfoniicus descrti- cola, although outside the range of this rabbit most collections have been from L. towiisendii and Sylvilagus species. Nymphs ha\e been col- lected from rabbits in every month of the year, with the peak season in May, June, July, and August. Since most collections have been in the nymphal stage, the peak seasons for larvae and adults are not known. After emergence from the egg, the larva at- taches to the host and feeds until fully engorged, then molts and transforms to a nymph while re- maining attachetl to the same host. The nymph does not drop from the host until it is fully engorged and ready to moll to an adult. The adult, lacking functional mouthparts, is not para- sitic and does not feed. Copulation and oviposi- tion take place on the ground. O. lagophihts has been reported to be nat- urally irifeeted with Rocky Mountmn spotted fever, Colorado tick fever, and tularemia. It has been shown to be capable of luirboring the tularemia organism, PasteurcUa tuhireiviis. for as long ;ls 676 days. Evidence indicates that O. lag- ophihts may be a potential reservoir of some dis- eases in nature, but not a direct vector in trans- mission from host to host. Twentv-nine drawings of some external an- atomical and morphological features in all stages of de\'elopment were made as a basis for the construction of a pictorial ke\' for the identifica- tion of species in the genus Otohius. ACKNOWLEDGMENTS Collections made throughout the western United States by various expeditions sent out from the Brigham Young University Department of ZoologN' and Entomology have been supple- mented by gifts and loans of sjx-cimens by several institutions, organizations, and individ- uals. The Rocky Mountain Lalwratory at Hamil- ton, Montana, through the courtesy of Glen M. Kohls, has been most cooperative. Dorald M. Allred of Brigham Young Universit)' supplied laborator)'-reared specimens which he had cul- tured when a member of the University of Utah Ecological and Epizoological Research Unit at Dugwav, Utah. The collections of ticks result- ing from the four-year (1959-1963) A.E.C.- B.Y.U. Ecology project at the Nevada Test Site, Mercury, Nevada, are in our possession. We wish to express appreciation to Glen M. Kohls and Dorald M. Allred for reviewing the manuscript and giving valuable suggestions. Some of the illustrations of adults and nymphs were made by L. Douglas Hill. Identification of specimens in our cx)llection was confirmed by Glen M. Kohls ;uid Ciirlton M. Clifford. The Department of Zoologv' and Entomol- ogy, Brigham Young University, supplied lab- oratory space, equipment, and supplies. REFERENCES Baclia. \Vm. J., Jr. 19.57. The life hi,stor>' of Otohiu.i LigoplUlus. J. Parasitol., 43(5) :560-565. Banks. \. 1912. New American mites. Proc. Eiitomiil. Soc. Wash., 14:96-99. Beck, D E. 195.5. Some unusual tlistributional records of ticks in Utah. J. Parasitol., 41(2) : 198-201. Beck, D E., D. M. Allred, and E. P. Brinton. 1963. Ticks of the Nevada Test Site. Brigham Young Univ. Sci. Bull., Biol. Scr., 4( 1 ) :1-11. Brown. J. H. 1944. The spotted fever and other Al- bertan ticks. Canadian J. Res., Sec. D, Zool. Sci., 22:36-51. Biological Series, Vol. 6, \o. 2, February, 1965 19 Brow-n, J. H. and G. M. Kohls. 1950. The ticks of Alberta with special reference to distribution. Can- adian J. Res., Sec. D., Zool. Sci., 28(3): 197-205. Chfford, C. M., G. M. Kohls, iuid D. E. Sonenshine. 1964. The systematics ot the subfamily Ornitho- dorinae (Acarina: Argasidae). I. The genera and subgenera. Annals of the Entomological Soc. of America, 57(4) :429-437. Cooley, R. A. 1932. The Rocky Mountain wood tick. Montana Agric. E.\per. Sta. Bull.208:l-58. Cooley, R. A. and G. M. Kohls. 1940. Two new species of Argasidae. Publ. Health Repts, 55(21): 925-933. Cooley, R. A. and G. M. Kohls. 1944. The Argasidae of North America, Central America, and Cuba. Amer, Midland Nat., Monograph 1:1-152. Dikmans, G. 1945. Check list of internal and exter- nal animal parasites of domestic animals in North America. Amer. J. Veterinary Res.. 6(21 ) :211-241. Duges, A. 1884. Turicata y garrapata de Guanajuato. La Naturaleza, periodico sientifico de la Socicdad Mexicana de Historia Natural, 6(1882-1884): 195- 198. Eklund, C. M., G. M. Kohls, and J. M. Brennan. 1955. Distribution of Colorado tick fever and virus-carry- ing ticks. J. Amer. Med. Assoc, 157:335-337. Evans, G. O., J. G. Sheals, and D. Macfarlane. 1961. The terrestrial acari of the British Isles, Vol. 1. British Museum of Natural History, London, Eng- land. Gregson, J. D. 1956. The Ixodoidea of Canada. Can- ada Dept. of Agric, Ottawa, Canada, Publ. No. 930:1-92. Hadwen, S. 1913. Report of the Veterinary Director General, Dept. of Agric, Ottawa, Canada, for the year ending March 31st, 1913, Appendix No. 9:74- 80. Hearle, E. 1938. The ticks of British Columbia. Sci. Agric, 18:341-354. Hewitt, C. G. 1915. A contribution to the knowledge of Canadian ticks. Trans, and Proc. Roy. Soc. Canada, 3rd Series, 9:225-239. Hoffmann, A. 1962. Monografia de los Ixodoidea de Mexico. I. Parte. Revista de la Sociedad Mexicana de Historia Natural, 23:191-307. Honess, R. F. and K. B. Winter. 1956. Diseases of wildlife in Wyoming. Wyoming Game and Fish Comm. Bull., 9:1-253. Hopla, C. E. 1955. Observations on the life history of a rabbit tick (Otobius lagophilus). J. Kansas Ent. Soc, 28(3):114-116. Kohls, G. M., D. E. Sonenshine, and C. M. Clifford. The systematics of the subfiunily Ornithodorinae (Acarina: Argasidae). II. Identification of the larvae of the Western Hemisphere, and descrip- tions of three new species. Annals of the Ento- mological Soc. of America, ( In press ) . Loomis, E. C. 1953. A note on Otobius lagophilus (Acarina; Argasidae). Pan-Pacific Ent., 29:198. Loomis, E. C. 1961. Life histories of ticks under lab- oratory conditions (Acarina: Ixodidae and Argasi- dae). J. Parasitol., 47:91-99. Neumann, L. G. 1896. Revision de la famille des Ixodides. I. Argasines. Mem. Soc. Zool De France., 9:1-44. Philip, C. B, J. F Bell, and C. L. Larson. 1953. 1956. Evidence of infectious diseases and parasites in peak population of black-tailed jack rabbits in Nevada, U.S.A., 1951-52. Proc. XIV Intern. Congress of Zool., Copenhagen, 1953. Copenhagen, 1956., 341- 342. Philip, C. B., J. F. Bell, and C. L. Larson. 1955. Evidence of infectious diseases and parasites in a peak population of black-tailed jack rabbits in Nevada. J. Wildl. Mgmt., 19:225-233. Pospelova-Shtrom, M. V. 1946. On the Argasidae system ( widi description of 2 new subfamilies, 3 new tribes, and 1 new genus ) . Meditsinskaia Parazit. i Parazit. Bolezni, 15(3):55-58. Rees, D. M. 1962. A study of the ecology and epizoo- logy of the native fauna of the Great Salt Lake Desert. Annual summary progress report of the staff of ecological and epizool. res., Ecol. and Epizool. Ser. No. 70, Univ. Utah. Rosasco, M. E. 1957. Seasonal abundance of the tick Demiacentor parumapertus on the black-tailed jack rabbit, with notes on otlier ectoparasites. J. Mammal., 38( 4 ) :485-490. Ryckman, R. E., C. C. Lindt, D. Spencer, and R. D. Lee. 1955. Additional collections of ticks from south- em California.]. Parasitol, 41(3) :280-282. Sil\ a-Goytia, R. 1953. Vectores y reservorios de la fiebre manchada Americana en Mexico. Cong. Intemaz. de Microbiol. 6( 2) :603-604. Silva-Goytia, R. and A. Ehzondo. 1952a. Estudios sobre fiebre manchada en .Mexico. Medicina Revista Me.xicana, 32(652 ) :217-221. Silva-Goytia, R. and A. Elizondo. 1952b. Estudios sobre fiebre manchada en Mexico. II. Parasites hematofagos encontrados naturahnente infectados. Medicina Revista Mexicmv.i, 32(654) : 278-282. Ab- stract, Trop. Disease Bull. 49(11):1137. Silva-Goytia, R. and A. EUzondo. 1952c. Estudios sobre fiebre manchada en Mexico. IV. Characteristi- cas epidemiologicas de casos de fiebre manchada ocurridos en la Laguna. Medicina Revista Mexicana, 32 (666): 569-579. Abstract, Trop. Disease Bull., 50:500. Strandtmann, R. W. and G. W. Wharton. 1958. Manual of Mesostigmatid mites parasitic on verte- brates. Institute of Acarology, Univ. of Maryland. Vest, D. E. 1957. A study of the ecology of infectious diseases in the native fauna of the Great Salt Lake Desert. Annual report of the resident director and staff, Ecol. Res., Univ. Utah. Vest, D. E. and Staff. 1959. Studies on the ecology and epizoology of the native fauna of the Great Salt Lake Desert. Annual report of the resident director and staff, Ecol. and Epizool. Ser. No. 41, Ecol. Res., Univ. Utah. Vest, D E. and Staff. 1960. Studies on the ecology and epizoology of the native fauna of the Great Salt Lake Desert. Annual suiimiary progress report of the executive chrector and staff, Ecol. and Epizool. Ser. No. 44, Ecol. and Epizool. Res., Univ. Utah. Vest, D. E. and Staff. 1961. Studies on Ecology of Q fever in native fauna in the Great Salt Lake Desert. Summary progress report. Institute of En- vironmental Biological Research, Ecol. and Epizool. Ser. 66, Univ.Utah. Woodbury, A. M. 1954. Ecology of disease trans- mission in native animals. Semi-annual report, 1 June to 30 November, Ecol. Res., Univ. Utah. Woodbury, A. M. 1955. Ecology of tularemia trans- mission in native animals. .Annual report of the director, Ecol. Res., Univ. Utah. Woodbury, A. M. 1956. Ecological check list. The Great Salt Lake Desert Ser., Ecol. Res., Univ. Utah. (.i' iWc^ \/^* .viUS. COMP. ZOOL BRIGHAM YOUNG UNIVERSITY SCIENCE BULLETIN AAAMMALS OF THE NEVADA TEST SITE by Clive D. Jorgensen and C. Lynn Hayward Biological Series — Vol. VI, No. 3 MARCH 1965 LIBRARY HARVARD UNIVERSITY, BRIGHAM YOUNG UNIVERSITY SCIENCE BULLETIN MAMMALS OF THE NEVADA TEST SITE by Clive D. Jorgensen and C. Lynn Hayward Biological Series — Vol. VI, No. 3 MARCH 1965 FOREWORD This is another in an extensive series of pubhcations on ihe fauna of the Nevada Test Site and desert ecologv resulting from studies made by tlie Department of Zoology and Entomology, Brig- ham Young L'niversity, in cooperation with the United States Atomic Energy Commission. The data reported herein are designed to furnish basic information concerning what mammals are present, where thev live, and when they are active. This information is essential to an evaluation of the ef- fects nuclear weapons testing, peaceful use of nuclear weapons, and nuclear warfare may have on mammal populations. Dorald M. .Allred, D Elden Beck, and Clive D. Jorgensen, Project Supervisors MUS. CO MP. ZOOL LIBRARY HARVARD UNIVERSITY. TABLE OF CONTENTS Page INTRODUCTION 1 ACCOUNTS OF THE SPECIES 2 Methods 2 Results 3 Sorex tenellus 3 Sorex merriami 3 Notiosorex crawfordi 3 Myotis ciilifornicus 3 Pipiitrellus hesperus 3 Conjnorhinus townsendii 3 Antrozous pallidus 3 SylviUigus nuttallii 3 Sylvilagus auduhonii 3 Lepus californicus 4 Eutavxias dorsalis 4 Ammospermophilus leucurus 4 Spemwphilus townsendii 4 Spennophilus variegatus 4 Spermophilus tereticaudus 6 Thomomys umhrinus 6 Perognathus formosus 6 Perognathus longimembris 7 Perognathus parvus 7 Microdipodops megacephalus 7 Dipodomys ordii 7 Dipodomys microps 8 Dipodomys merriami 8 Dipodomys deserti 8 Reithrodontomys megalotis 8 Peromyscus crinitus 9 Peromyscus eremicus 9 Peromyscus maniculatus 9 Peromyscus trueii 9 Onychomys torridus 9 Neotoma lepida 9 Lagurus curtatus 9 Erethizon dorsatum 9 Canis latrans 10 Vulpes macrotis 10 Bassariscus astutus 10 Mustela frenata 10 Taxidea taxus 10 Spilogule gracilis 10 Felis concolor 10 Lynx rufus 10 Dama hemionus 1 Ovis canadensis 1 Equus caballus 1 Bos taurus 1 ACTIVITY AND BEHAVIOR 1 Daily Activity 1 Methods 1 Page Hfsults 26 Diodomys microps 17 7. Collection sites of Dipodomys merriami 18 8. Collection sites of Ammospcrmophiltis knicurus 19 9. Collection sites of Lcpux ccilifornicus 20 10. Collection sites of Tlwmomys umbrinus, Sylvilagus audubonii, and Sylvilagus nuttallii 21 11. Collection sites of Eiitamius dorscial traps and were acti\atcxl for three consecutive davs (see .\llred. Beck and Jorgen- sen. 1963a for details of each trapping design.) Large mammals wvre routinely ideijtified w ith sight observations of the animals themselves and their readily identifiable signs, e.g. feces, tracks, etc., thougii specimens were collected for almost all species. Some species were rou- tinelv recorded from vehicle kills on the high- ways (e.g. Black-tailed Jack Rabbit) wliile others Biological Series, Vol. 6, No. 3, Mahch, 1965 were recorded only after they had been killed by veliicles or predators. All field records were accompanied by ob- servations of the plant conimunity so that tlie spatial distributions and biotic communities could be coordinated for each species. Most of the specimens collected wliich were not marked and released were retained for further studies and many (466) were prepared for museum specimens. These data are presented in this section. Results Sorex tenelhi.^ Meniam Inyo Shrew Three specimens: August 12, 21; April 9. All specimens were collected from the Pin- yon-Juniper community (Jorgensen and Hay- ward, 1963). Sarex merriami leucogenys Osgood Merriam's Slirew One specimen: October 31. This specimen was collected from the Pinyon- Juniper community (Jorgensen and Hayward, 1963). Notiosorex crawfordi crawfordi (Coues) Desert Shrew One specimen: October 11. This specimen was collected from a rather mesic canyon of the west slope of Ranger Moun- tain. Myotis californicus stephensi Dalquest California Myotis Five specimens: August 3; November 28. For many years this race was known by the subspecif ic name pallid us. Dakjuest ( 1946 ) found pallidus to be preoccupied and proposed the new name stephensi for this distinctly paler inland desert race. All specimens were collected from artificial caves and were not associated with any par- ticular biotic community. Pipistrelliis hespertis hespcrus (H. Allen) Western Pipistrella Fifteen specimens: from May to October. These small bats were probably the most numerous of all bats at the test site. Observed flying in areas where insects were attracted by either lights or water, they were most abundant during the early evening. However, some were observed for most of the night. Corynorhinus toiciiscndii pallesccns Miller Townsend's Big-eared Bat Five specimens : October 22; November 28. The races of this species seem to be separated exclusively on the basis of color. The specimens from die test site are somewhat darker dian specimens of pallescens from southern California but decidedly paler dian intermedins. Hall (1946) comments that this is also the case widi the Nevada specimens he examined. This species was collected entirely from the vicinity of standing water. Antrozous pallidus pallidus (LeConte) Pallid Bat Four specimens: May 1; July 1, 8; August 11. On the basis of size (average length of 3 females and 1 male, 107.7 mm) the test site specimens are closer to typical pallidus tlian to pacificus. This species was observed and collected pri- marily from the vicinity of standing water. One was collected by Killpack and Goates (1963) in a Museum Special trap set for small mammals. Sylvilagus nuttallii grangeri (J. A. Allen) Nuttall's Cottontail (Fig. 10) One specimen: November 21. This secretive species was observed primari- ly in the Pinyon-Juniper community, and never on the valley floors. Sylvilagus audubonii and nuttallii overlapped their ranges at the bases of mountains which were topjjed with Pinyon and Juniper. Although few were collected and only one preserved, they were not uncommon in their preferred community. This species seemed to be much more secretive and shy than audt4bonii. Sylvilagus audubonii arizonae (J. A. Allen) Desert Cottontail (Fig. 10) Eight specimens: August 4, 25; November 1, 22, 28. This species usually occupied shelters pro- vided by abandoned structures, of which there are many scattered throughout the test site. They were also found inhabiting the natmal shelter of rock outcrops and dense cover of sagebrush. Collections and observations were made from Larrea-Franseria, Grayia-Lycium, Coleogyne, Bricham Younc Unive3«ity Science Bulletin Salsola, and Pinyon-Jiinipcr communities, al- being observed only sparsely in areas where the though it was probably the shelter of abandoned upper bajada meets the base of mountains c-on- stnietures in these areas that attracted them. taining Pinvon and Juniper. Lejms calijornicus descrticola Mearns Black-tailed Jack Rabbit (Fig. 9) One specimen: January 9. Tliis wiUT species was observed and collected in all the biotic communities as well as the transition areas between. On several occasions large numbers were attracted to small mammal study grids where they robbed the traps of their bait (Jorgensen, 1962). They were observed and collec-ted from Larrea-Franseria, Grayux- Lycium, Coleogyne. Atriplcx-Kochia, Salsola, and Pinyon-Juniper. Leptts califcfrnicus lexianus Waterhouse Black-tailed Jack Rabbit About 500 specimens of this subspecies pur- chased from a commercial supplier in Fort Sum- ner, New Mexico, were released at the test site during the first part of April, 1959 by personnel from the University of Califoniia, Ix)s Angeles (personal communication from Page Hayden, December 12, 1961). Several specimens were captured a few days later, after which the pro- ject was discontinued. The last specimen was seen at Jackass Flats, July 6, 1959. Etttamias dorsalis griimeUi Burt Chff Chipmunk (Fig. 11) Twenty-six specimens: April 26, 27; August 1; September 14, 16; November 29. Specimens of dorsalis from the VViisatch .\Ioimtains of c-entral Utah were somewhat larg- er in nearly all measurements taken when com- pared with the test site material. The lesser in- flation of the braincase ascribed to cies was obser\ed and collected only from the heavily wooded Pinyon-Juniper cx)m- munitv. Biological Series, Vol. 6, No. 3. March, 1965 ippeajq [Eiiqjoja^ui 4sK3q H-^ ippcajq {EIUVJ3 q;pc3jq opEuio^A^ Ijn^s JO 4;5U3I 4O0J q}2u3i p^jox jaquinjvj iunasnj\ q}Su3| JESBfJ ippi!3jq lC4iqjoja}ui jsBa^ ippROJCj [BttlUJ^ tppcajq oi4Biuo§X2 n"1S JO ipSua^ 4S3JP9JQ ipSuaj 40o,{ tpSuaj jrex 1[4SU3I IB40X jaquirijY ranasnj>j QO 00 00 Oi n m Oi t~ »n CO CO eq eo t-; Oi a Oi Oi 05 00 05 CO rH eq (M c^ CO CO CO CO 00 — I 00 O -1 in ID CO t-^ 00 00 00 CD CO lO lO CO ^ a> 00 oq CO as 00 CO 00 o> -H p >ra 00 q ■*' ^ CO CO ■*' cO CO CO CO CO CO CO CO CO CO Oi a oi 00 Oi oi o o rt — ( rt oi ^ ■-I CO U5 CD >ri lO Tf »f5 CO CO CO CO (M ^ (M IN — I CO CO CO CO CO (M (N (M <3^ 00 —1 -H -< (M 00 00 00 CO m CO 00 o> a> CO CO CO CO CO. CO lo CO ira O rt o (N (N OJ Bkicmam Young University Science Bulletin Spcniuipliilus tcrcticaudus tercticauclu.s Baird Hound-tailed Ground Squirrel (Fig. 12) Two specimens: July 16; August 9. This squirrel was collected from Larrca- Franseria onlv. Thomonujs uiiil)iiiiits tidiius llal! Southern Pwket Clopher (Fig. 10) Si.xteen specimens: January 26; February 16; March 7, 16, 17, 22, 26, 28; j'une 16; November 6; December 15. Our specimens agree rather well in skull measurements with tliose of the smaller race mnus as described by Hall (1932, 1946). Our male specimens measure slightly larger both in body and skull than tliose measured by Hall; however, our females are almost identical, es- pecially in skull measurements (Table 2). The test site specimens also exhibit the darker than cinnamonbuff and black postauricular patch mentioned bv Hall. The t\'pe locality for n(inu\ is given as 5.5 miles northwest of W'hiterock Spring, Nye County, Nevada. This species was collected from the valley floors most frequently, although some were found living among the rushes at Cane Springs, where they constructed an extensive system of runways. Burrows were more numerous in areas with loose soU, particularly in the Larrea-Franseria (Lyciiim pallidum association) community in Frenchman Flat. They were collected from Lar- rea-Franseria, Crayia-Lycium, and Atriplex- Kocliia communities. Perogmithua fonuuxus mohavensis Huey Long-tailed Pocket Mouse (Fig. 4) Twenty-three specimens: NLircli 10, Julv 13; September 18, 21, 27. On geographical grounds tlie test site popu- lation of formastts falls within the area occupied by the subspecies mohavtmis (Hall, 1946; Hall and Kelson, 1959). Compared with near topo- types of P.f. farmosus from Washington County, Utah, skull differenc-es are difficult to detect except that the Nevada specimens (adults) do have a slightly more inflated tvnipanic bulla. According to Huey (19.38) in his original de- scription of mohavcn.'iis this race is sup[X)sed to have less inflated bullae than formostis, but Dur- rant ( 1952 ) found the opposite to be the case. Our observations tend to confirm Durrant's analysis provided we are actually dealing with Huey's race. From the standpoint of color, most of our specimens possess the lighter quality as- cribed to nwhavensis but a few specimens are almost identical with topot\pes of formost4s in tliis respect. Since we ha\e not had an oppor- tunity to compare Huey's type material with our series, we are still uncertain of the possible intergradation at the test site. This species was collected from all of the biotic communities, although more abundant in some than others. On the valley floors, it seem- ed to prefer deep soils w ith small rocks scattered throughout. It was also one of the few found to inhabit the desert pavement. Specimens were c-oUected from Larrea-Franseria, Cravia-Lvcium, Coleogyne, Atriplex-Kochia, Salsola, Pinyon- Juniper, and the dr\' mountain ranges. Table 2. Measurements of Thomomys umbrinus from the test site. Museum number Basilar length Zygomatic breadth Least interorbital breadth Mastoidal breadth Nasal length Total lengtli Tail loni;th Foot length Female 4068 28.3 20.2 6.5 17.3 11.1 185 55 26 4480 27.2 18.6 6.3 16.7 10.5 176 66 24 4161 28.9 20.8 6.6 17.7 10.5 205 57 25 4063 28.8 19.8 6.4 17.9 11.3 195 48 26 Avg 28.3 19.8 6.5 17.4 10.8 190 56 25 Male 4482 30.0 21.6 6.8 18.4 11.8 200 65 25 4064 31.7 23.0 6.5 19.7 12.5 227 70 26 4066 31.2 22.8 6.5 18.6 13.5 230 66 28 4067 28.2 20..5 6.6 17.2 12,5 185 55 25 4065 28.6 20.2 7.1 17.7 11.6 197 70 27 Avg 29.9 21.6 6.7 18.3 12.4 208 65 26 Biological Series, Vol. 6, No. 3. March, 1965 Perognathus parvus olivacetts Merriam Great Basin Pocket Mouse (Fig. 11) Si.xteen specimens: March 25; June 21; Aug- ust 1; September 16. The community distiibution of this species was difficult to determine because of their spar- city and tlie conditions under which they were collected. Generally, they were most frequently collected in Coleogyne and Pinvon- Jumper com- munities, although one of the highest popula- tions obser\'ed was in a Grayia-Lycium commun- ity which had been denuded by nuclear weapons testing about four years earlier. Collections were also made in Kawich Valley, north of the test site, which is more typical of Great Basin vege- tation. They were collected from Larrea-Fran- seria, Grayia-Lycium, Coleog\ne, Salsola, Pin- yon-Juniper, and the dry mountain ranges. They appeared to be scattered in low densities throughout tlie entire test site, but concentrated in only a few. Perognathus loiigimembris (Coues) Little Pocket Mouse ( Fig. 2 ) Thirty-one specimens: March 15, 29; April 7, 16, 27; June 14; July 8, 9; August 3, 4, 20. Although we have a large series of specimens of P. loiigimembris from the Nevada Test Site, their subspecific status is not clear. Their gen- erally smaller measurements would indicate that they come closer to paiuiiuinfinus of eastern California and western Nevada, but there mav be some intergradation especially in the lower valleys with virginis, named orginally from southwestern Utah by Huev (1938). This species was collected from all biotic communities except Pinvon-Juniper. They seemed to prefer soils which were relatively deep but over-laid with small rocks. They were collected from Larrea-Franseria, Grayia-Lycium, Coleogyne, Atriplex-Kochia, and Salsola com- munities as well as the marginal areas between dry mountains and the upper bajadas. Microdipodops megacephalus sahidonis Hall Dark Kangaroo Mouse Three specimens: April 25. The few specimens at our disposal seem to fit well tlie description gi\en by Hall (1946) for the race sahidonis. The darker color, longer tail, and plumbeous rather than white bases of the ventral hairs and smaller skull distinguish it from the races paididus and megacephalus that have adjoining ranges. Altliough we expected to collect tliis species on die test site, it was collected only from an Artemisia tridentata community in Kawich Val- ley north of the test site. Dipodomys ordii monoensis (Grinnell) Ord's Kangaroo Rat ( Fig. 1 ) Ten specimens: Januar)' 22; March 10; June 21; October 3, 7. The Nevada Test Site lies in an area where the D. ordii races monoensis and fetosus are likely to overlap. Compared \vith a series of fetosus from western Millard County, Utah, the test site specimens have longer tails and feet, but the size of the skulls is about the same. Accord- ing to Hall ( 1946 ) monoensis is smaller than fetosus with respect to the above measurements but the difference is not great. Comparing speci- mens in bright pelage, taken in October and September, the test site series is decidedly more reddish on the whole but individual specimens can be selected that match closely with the Utah series (Table 3). This color difference seems to be the best justification for assigning our speci- mens to the race monoensLi. Table 3. Comparative mea.surement.s of adult Dipodonujs ordii from the Nevada Test Site and Millard Co., Utah. Nevada Test Site Series Millard Co., Utah Series D. 0. vionoen.sts D. , 3. fetosus Museum TaU Foot Basal Greatest Museum Tail Foot Basal Greatest number length length length breadth number length length length breadth 4477 144 42 26.1 23.7 2674 136 40 26.0 23.4 4478 135 41 25.6 23.5 2677 134 39 26.1 23.1 4075 142 39 25.1 23.4 2675 133 37 26.1 23.3 4076 145 40 26.1 23.7 2673 141 39 26.8 24.0 4036 133 40 26.3 23.5 2681 129 40 25.7 23.8 4037 130 38 25.8 23.3 2676 135 40 26,9 23.7 4038 134 38 26.8 23.2 1474 132 39 26.0 23.2 4039 135 41 26.2 23.8 Avg 137.2 39,8 26.0 23.6 134.3 36.3 26.2 23.5 Bkicham Vounc Univebsity Science Bulletin The community distribution of this species was difficult to determine since it was widely c-oUected, but never especially abundantly. It w;is most frequently collecti'd from areas dis- turbed h\ nuclear weapons testing. It was col- lected from Larrea-Franseria, Grayia-Lycium, Coleogvne, Salsola, imd several marginal areas adjac-ent to these communities. Dipodomijs microps occiclentalis Hall and Dale Chisel-toothed Kangaroo Rat (Fig. 6) Twentv-nine specimens: March 4, 15, 16; July 11; August 21, 27; September 4, 10, 16, 21; Oc4ober 3, 8; November 5, 11, 13. In me;isurements the Nevada Test Site ser- ies approaches nearer to the smaller occidentalis than centralis (Hall, 1946), both with respect to external body measurements and several skull measiu-ements although the skull measurements are not strikingly different in most instances (Table 4). W'c have seen no specimens of centralis for cximparison of color. This species was the most widely distributed kangaroo rat at the test site. It was collected from Larrea-Franseria, Grayia-Lycium, Coleo- gyne, .^triple.x-Kochia, Salsola, and the dry mountain ranges, but it was rather rare in the Larrea-Franseria. Dipodomijs merriami merriami Meams Merriam's Kangaroo Rat (Fig. 7) Twentv-eight specimens: Febniary 26; March 10; Julv 11; August 2, 18, 20, 21; September 4, 10; November 17, 28. Hall (1946) recognizes only the one sub- species (merriami) from Nevada. While tliere appears to be a gradient in certain measurements from south to north, particularly tail length, no clear-cut races can be recognized, according to him. Tliis species was collected from all of the communities in the vallevs, although usually least abundantK' in the Coleogyne and Atriplex- Kochia. In one case, Mid-Valley, it was tlie most abundant species of kangaroo rat in Artemisia tridentala stands and \irtually absent from ad- jacent Colcoi^i/ne stands. They were c-ollected from Larrea-P'ranseria, Grayia-Lycium, Coleo- gyne, Atripk'x-Kochia, Salsola, and foothills sur- rounding the valleys. Dipodomijs deserti deserti Stephens Desert Kangaroo Rat (Fig. 1) Twenty-one specimens: February 3; March 18, 23; July 31; August 2, 3, 25. Hall ( 1946 ) was unable to find sufficient \ariation in the Nevada population of deserti to justify subspecific names and dierefore included all of liis material in tlie race deserti. This species had a very limited distribution at the test site. It was found entirely in areas which showed some e%'idence of disturbance, particularly man-made disturbance, and was most abundant in Frenchman Flat on the playa where dikes had been constructed to divert water. \\'herever found, they were always in loose and/or sandy soil. Specimens were collect- ed from Larrea-Franseria and Salsola communi- ties. Reithrodontomijs meer. Peromyscus truci truci (Shufeldt) Piiion Mouse (Fig. 13) Six specimens: March 29; .April 26; May 19; June 6; July 6. This species was trapped almost entirely from the Pinyon-Juniper community and the foothills adjacent to it. One specimen was collected in Grayia-Lycium, but near a rocky outcrop at the base of a mountain on which Pinyon-Juniper occurred. Omjchomys torridus longicaudus Merriam Southern Grasshopper Mouse (Fig. 5) Fourteen specimens: June 14, 16; July 11; September 5, 11; October I, 5, 27; November 1. This species was trapped from all communi- ties, although it was apparently not abundant anywhere. Neotoma lepida lepida Thomas Desert Wood Rat ( Fig. 1 ) Seventy-nine specimens: January; June; July; August; September; October; November; De- cember. All of the specimens for which the baculum was saved possessed the long, slender, and curved structure characteristic of lepida (Burt and Barkalow, 1942). The characteristic of all the hairs on the venter being plumbeous at the base as gi\en frequently in descriptions and keys is by no means true in many specimens of lepida, not only in the test site aiea, but elsewhere. The amount of pure white ventral hairs varies in the test site material from a small pectoral spot to an extension onto the throat and even the chin. It frequently also extends well down onto the belly. As one would e.xpect this sj>ecies was col- lected most abundantly in the mountainous areas where its shelters could be built in the pro- tection of the rocks. They were also found on the valley floors in areas of extensive Yucca on the bajada. On occasion, they were collected some cUstance from any appiirent shelters or areas suitable for shelters. This led us to sus- pect they moved over the valley floors more frequently than might be expected in view of their usual nesting habits. They were collected from Larrea-Franseria, Grayia-Lycium, Coleo- gyne, .Atriplex-Kochia, Salsola, Pinyon-Juniper and dry mountain ranges. Lagurus curiatus curtatus (Cope) Sagebrush Vole (Fig. 13) One specimen: April 12. The single specimen is placed in the sub- species curtatus entirely on a geographical basis. Intergradation between curtatus and iiitermedius occurs in the general area of the test site ( Hall, 1946). The specimen was collected from Pinyon- Juniper, but may also be present in Artemisia tridentata which coinhabits certain areas with Pinyon and Juniper. Erethizon dorsatum (Linnaeus) Porcupine Although seat of this species was occasionally seen in Pinyon-Juniper, the only specimen re- corded was killed on a highway in Larrea-Fran- seria, about 20 miles from the nearest Pinyon or Juniper. 10 BnicHAM Young University Science Bulletin Canis latrans Say Coyote (Fig. 14) Four sjxvimcns: February 8; August 17; November 22; Dec-ember S. The Nevada Test Site lies in an area of in- tergradation of C. /. Icstes and C. /. mearmi (Hall, 1946). It seems evident that this area of intergradation is very wide and we have insuf- ficient comparative material to assign a sub- specific name. Either signs were seen or specimens c-ollected in all of the communities. Vulpcs macrotis Merriam Kit Fox (Fig. 14) Seven specimens: January 19; Febniary 16; September 14; Dec-ember 18, 22, 30. Both the races nevadensis and arsipiis are listed for Nye County by Mall (1946). He stated that nevadetisis differs from arsipus in that it has "black instead of brown or grayish upper lips, dark instead of light-colored forehead and usually black instead of always brown tip on tail." We are unable to see any color variations in our material that would indic;ite any racial difference between the test site material and specimens from farther north in the Great Basin which were assigned by Hall to the race nevad- ensis. The possible effect of taiming on colora- tions complicates ade(juate compiuisons. Com- parison of skulls which appeared to be of about the same age indicated that in most cases the braincase in the more northern Great Basin specimens tends to be more inflated than in those from the test site, although this was not always the case. Judging from the material at hand, it would seem that if there is justification for the recognition of two geographical races the test site population is intermtxliate Ix^tvveen them. We therefore hesitate to assign it a sub- specific name. Kit fo.xes were unusually abundant in many areas and signs were observed in Larrea-Fran- seria, Grayia-Lycium, .\triple.\-Kocliia, Salsola, and the foothills surrounding the valleys. Bassariscus astutus nevadensis Miller Ringtail One specimen: September 22. This specimen was collected from Pin\'on- Juniper. Mustela frenata iwvadensis Hall Long-tailed Weasel One specimen: May 15. This species w;is collected only once, after one had been killed on a highwav in Gravia- Lycium. It was killed only a short distance from a spring with rather dense slirubb\' vegetation, and this rather than the open desert floor was suspected to be its habitat. Taxidea taxits (Schreber) Badger (Fig. 14) Four specimens: June 30; July 9, 16, 13. Our specimens appcnir to be intergrades be- tween T. t. ta xus dnd T. I. hcrlandieri. One adult skull suitable for measurements was narrower across the z\'gomatic arches ( 81 mm ) and across the miistoids ( 77.3 mm ) than specimens of T. t. taxus from central Utah. In all of the test site specimens the white dorsal stripe extends well back to the shoulders and is decidedlv longer than that of central Utah specimens. This stripe never extended anywhere near as far back as the base of the tail as it is supposed to do in some individuals of hcrlandieri. Badgers seemed to appear almost anywhere in the valleys, but were not observed or cx)llected from the mountainous areas. They were cx>lJected or recorded from Larrea-Franseria, Grayia-Ly- cium, Coleog)'ne, Atriple.x-Kochia, and Salsola. Spilogale gracilis Merriam Western Spotted Skunk On a geographical basis the spotted skunks of the test site might be either S. g. gracilis or S. g. saxatilis; or both subspecies might also be present. Without specimens it is not possible to identify the subspecies. Felis concolor kaibahctisis Nelson and Goldman Mountain Lion Sight records were made entirely from the mountainous areas and the Pin\(>n-Juniper com- munity. No specimens were collected. Lt/nx rufiis hailei/i Meniam Bobcat One specimen: Jul v. On the basis of paler color, smaller size, and smaller skull, the specimen a\'ailable to us ap- pears to be the race bailciji rather tlian palle- scens. Biological Series, Vol. 6, No. 3, March, 1965 The bobcat was observed primarily on the upper bajada, although it was also sighted on the valley floor and mountainous areas. It was sighted and/or collected from Larrea-Franseria, Grayia-Lycium, Coleog\'ne, and the mountain- ous areas. Though not seen in the Pinyon-Juni- per, it is assumed to be present. Duma hemionus hemionus (Rafinesque) Mule Deer Although this species was occasionally sight- ed on the valley floor and upper bajadas, it in- habited primarily the Finvnii-Juniper community or mountainous area^ uhitli were capped with Pinyon ami Juniper. OLUi camuleiibis nthani Merriam Mountain Sheep Mountain sheep were never observed oi col- lected from the test site, but they were observed in the mountains around it. Also, scat be- lieved to belong to mountain sheep was fre- quently seen among the low, dry mountains east of Frenchman Flat. It is very likely that they occasionally enter the test site when crossing from one mountain range to another, particularly in the winter and spring months when water is more plentiful. Equus caballits Horse Horses have been rather abundant at the test site in former years. At the present, only a few small bands inhabit the mountains on the west side of the test site. They are frecjuently seen near tfie several springs, e.g Cane Springs, VN'hiterock Spring, and Tippipah Spring. Bus ttiui ua Ca)w Cattle are maintained bv the Atomic Energy ("onimission and are found grazing throughout the test site. V\'ater is supplied, thus allowing thein to spend rather long periods of time on the valley floors. ACTIVITY AND BEHAVIOR Activity is a tenn which has been used many different wavs and determined with a rather wide variety of metfuxls. It is freijuently dif- ficult to interpret fjecause of the difficulty in isolating the influence e.xerted on the results by the method of sampling or niea.suring. If this influence is not understoiid, tlie investiga- tor could form inferences and possibly conclu- sions c-oncerning the populations that are in error. Evidences of activity in our studies are based entirely on the trapping data and are in every case subject to the influence the traps themselves may have had on the animal's })e- havior. Our conclusions are necessarily drawn with these limitations in mind. Data will be presented concerning the activi- ty of individuals as well as the activity of the population; however, only certain species are disiussed with respect to each phase of activity. Since many species were not present in our samples, data concerning tlieir activity simply are not availaV)le. DAILY ACTIVITY Ecological investigations of the fauna at the Nevada Test Site have resulted in considerable data concerning the activity of A. leucurus, P. lungimembris, D. anlii, D. microps, and D. mer- lUitni. This section discusses some aspects of daily activity and activity fluctuations of these species relative to seasons, meteorological condi- tions, se.\ ratios, movement, and competition. Daily activity cun'es have been demonstrated for several species in North America: D. mer- ruimi (Reynolds, 1960), Microtus (Hamilton, 1937; Calhoun, 1945; Pearson, 1959), Neotoma (Spencer, 1941), Sigmodon (Callioun, 1945), Hiithrodontomi/x (Pearson, 1959). Bartliolomew and Cade ( 1957 ) suggested that no daily per- iods of dormancy were evident in P. longimem- bris. Methods Trappuig incidence was used as the index to demonstrate the time of day when activity was most intense as well as the way in which populations reacted to climatic changes in their emironment. Two trapping designs were used. The first was a single U-shaped transect which contained 200 Young-type live small mammal traps spaced at 9.2 in (.30 ft) intervals, and baited with rolled oats. This transect (designated as 5CP) was 12 Bhicham Young Univehsity Science Buuletin f.:-^; PAHUTE MESA >["fy>jNDU;V Figure 1. Collection sites of Dipodomtjs deserti (triangles), Dipodomys ordii (squares), and Neotoma lepida ( circles ) . 3IOLOCICAL Series, Vol. 6, \o. 3. March, 1965 13 Figure 2. Collection sites of Perognathus longimembris. BmoHAM VouNc University Science Bulletin Figure 3. Collection sites of Pcmmyscu.s crinitus. Biological Series, Vol. 6, No. 3. March, 1965 15 PAHUTE MES/1 ■■\1 MOU L D Figure 4. Collection sites of Pewgnathus formosus. 16 Bnir.iiAM Young Un^'ersity Science Bulletin Figure 5. Collection sites of Onycliomys torridus. Biological Series, Vol. 6, No. 3. M.^rch, 1965 17 L □. Figure 6. Collection sites of Dipodomys microps. 18 BiiiciiAM Young Univehsitv Science Bulletin i m- ii r ii ^ / M'^^'^.^Mf^ I LARREA- FRANSEfllfl f.RAYlA - lyCIUM '^ D DCMIA C( D ATRIPLEX-KOCMH MOUNTAtNOUS AREA I 1 f if TEST SITE I^^Sfei Kigiir<' 7. Collcclion sites of Dipoclomij.i mcrriami. Biological Series, Vol. 6, No. 3, March, 1965 19 PAHUTE ME A ^VEST STE BOONDiR'^ ^'''"''" '^ ' Figure 8. Collection sites of Ammonpermophilus leiwurus. 20 Bhiciiam Young University Science Bulletin i* TEST sue eoufj^ Figure 9. Collection sites and sight records of Lcpiis culiforiiicus. Biological Series, Vol. 6, No. 3. March, 1965 21 ' PAHUTE MESA ' ; V TEST SITE'eOUNDfiRY^ r LARREA-FRANSER A GRAYIA LYC UM &s^^3 n ATRIPLEX-KOCHIA COLEOGYNE m n SALSOLA E3 „ NTAINOUS Afi .■ L. 1 1 Figure 10. Collection sites of Thomomtjs utnbrinus (circles), collection sites and sight records of Sylvilagus audu- bonii (triangles) and Sylvilagus nuttallii (squares). 22 Bhiciiam Vounc; Univkksitv Science Bulletin MOUNTAINOUS *Re n L_.._...X3_ KigiiR- 11. Collection sites of Eulamius dorsalis (sfiiiares), Pcrognalhiix partus- (circles), and Reithrodontomys megalotus ( triimgles ) . Biological Series, Vol. 6, No. 3, M.\bch, 1965 23 Figure 12. Collection .site.s of Spcnnophilus varicgutus (ciTcles), Spennophilus townsendii (squares), Spermophilus tereticaudus (triangles) and Pcromysctis eremicus ( sla.shed circles ) . 24 Hhi(;ha.m VoiNc Univeksity Science Bulletin t'^^ ^^5T^ TE |*5;.U«,H^^^' / ") ^^M^.k/'t^ ^z/- :TUOV AREA eOUNOART-.-. Figure 13. Collection sites of Pcromijscus maniciilatus (cinles), Peromijscus truci (squares), iuid Laguriis curtatus ( triangles ) . Biological Series, Vol. 6, No. 3. .March, 1965 25 Figure 14. Collection .site.s and sight records of Taxidea taxus (circles), Viilpcs macroiis (tiiangles), and Canis latruns ( squares ) . 26 Bhigham Young University Science Bulletin located in a Ltjcium fxillidiim plant c-ommunit)'. Other plant spec-ies associated in this comiminity are Ltjcium mulcrsonii. Crmjiii spiiwso. Eurotia lanuta. Alriplcx aincMCiis, Alhplcx confcrtifolui. Dalca polijadcuUi. Larrea divaricata, and Ory- zopsis hijmemndcs. Tlie "second design (designated as IF) was a grid consisting of six transects, each witli 12 Young-tspe live small mammal traps. Tlie tran- sects and the traps were 22.9 m (75 ft) apart; thus, the grid covered 31.2 ares (7.81 acres) and contained 72 traps. Study IF was located in an area in Yiict-a Flat which had previously been denuded of its original vegetation by nuclear weapons testing between 1952 and 1957. The grid was in a Salsoh kali plant community. Other plant species c-ommon in tliis area were Onjzopsis htjmenoidcs, Chaciuictis stevioides, and several other less abundant annuals. See Allred, Beck and Jorgensen (1963b) for the precise location of 5CP and IF. Traps were checked once each hour for 48 constK-utive hours each month from February tlirough .August. Before animals from 5CP were released, the date, time of capture, species, se.\, stage of development, and ambient temperatures were recorded. The animals from IF were marked with a combination of ear and toe cUps and their identifying marks were recorded along with the data listed above before they were released. In this manner the activity of individ- uals as well as the population was recorded. Temperature readings were taken 3 dm ( 12 in.) below ground sm-face, upon ground, and 12.19 dm (48 in.) above the ground surface. Temperatiu-es were mea-sured with a Tele-ther- mometer.' Meteorological factors such as cloud cover, wind, and phase of the moon were also noted. Sunrise and sunset were rec-orded for each plot since tlie time period differed slightly between them. Results Dial Cycles Since hours Ix-twcen sunset and sunrise vary slightly from month to month, any one time of dav cannot be inteqireted efjually each month. To effect an equal staitiiig point, sunset wiis selected us a c-ommon starting point for each night's observations, and the hours of the night enumerated as iiours after sunset. This adjust- ment became nec-essary when it was evident that the time of sunset Wius import;uit in the activity of tlu-se desert sjX'cies of small mammals. Fig- ure 15 presents a summar\' of the diel activity PwraiWIlmi WOfUKMt*'!* QL. Di J L J L tk- th- Figure 15. Composite graph depicting the percent of total captures plotted for each hour after sunset, and for the time of day when they were captured. when plotted before (time of capture) and after (hours after sunset) the adjustment for sun- set. Because the length of the nights varies dur- ing the year, obsei-\ ations at the right ends of the curves do not represent identical conditions of light. Activitv of D. mcrriami. D. microps. D. ordii, and P. lonf]^imcml)ris was nocturnal, beginning soon iifter sunset and frecjuently persisting for 'Tele-fhermometer, models 43TC and 43TE, manufactured by Yellow Springs Instrument Company, Inc., Yellow Springs. Oliio. Biological Series, Vol. 6, No. 3. March, 1965 27 a short time after sunrise. Activity of A. leucunis was entirely diurnal. Dipodomijs onlii and D. merriami had activity peaks near the second hour after sunset and again between the eighth and tenth hours. Dipodomijs microps also had two peaks, but the first appeared about the fifth hour after sunset rather than the second. Perog- nathus longimembris reached its activity peak on the second hour after sunset, maintained it through the fifth hour, and then decreased. From Figure 15 it is apparent that the mode of plotting can make considerable difference in the interpretation. This is particularly evident in the IF study plot. It is our opinion that plotting of these types of data should be adjusted to some common denominator such as sunset, in order that a more realistic concept of their dial activity can be estabUshed. This seems more reliable even though the right ends of the curves are not directly comparable. Hourly Fluctuations Aside from an obvious temperature decrease at the time activity' commenced and a subse- quent increase when activity subsided, no cor- relation was evident between animal activity and temperature fluctuations (Fig. 16-28). Dipodomys merriami, D. ordii, and D. mic- rops - There was no correlation between moon- light and trapping activity. For example, some extreme activity fluctuations were observed in IF during July (Fig. 28) and the moon was never obstructed by clouds. Similar fluctuations were observed in May (Fig. 26) when the moon was frequently concealed by clouds. These con- cealments were not correlated with depressions or peaks in animal activit)'. During the April 21- 23 period in 5CP (Fig. 18) when the moon set near midnight there was a distinct increase of activity after the moon went do\vn on April 22, but not on April 23, indicating that there was not a consistent correlation between the lunar events and small mammal activity. Perognathus longimembris - A sizeable in- crease was recorded at a time when the moon was concealed by heavy clouds at 0300* hours on May 31 (Fig. 19) in 5CP. Short periods of cloudiness had less influence than periods of sustained moonlight interrupted by less fre- quent cloudiness. Fluctuations did not appear to deviate from the diel cycle on nights when there was no moon. Intermittent rains and cloud- iness began at about midnight and lasted for nearly three hours on August 18-19 (Fig. 22) in 5CP. This suppressed activity. A similar reaction was evident on the following night when it rained from 2200 to 2400 hours. The rain ceased for t\vo hours and activity increased, but dropped abruptly with more rain. Sex Ratios There were no significant differences^ be- tween the numbers of males and females, yet the ratios differed from one night to the next. Correlations were not evident between these ratio changes and the meteorological changes. Dipodomys microps was the only species vvitli a significant'' seasonal change in its sex ratios. The ratio switched from predominantly males in February and March to predominantly females in May, June, July, and August. The ratio was even during April. The sexes were simultaneously active each hour for there were no significant differences" in the hourly ratios. Tlie right-hand tail of the activity curve (Fig. 15) was excluded from this analysis to avoid possible exaggeration as a re- sult of small numbers being trapped. Individual Activity The activity and number of individuals ac- tive was examined to determine if their activity influenced population data and diiily activity curves. Tliis was determined by using marked D. merriami and D. ordii trapped in IF. The total number of animals trapped is of particular interest because it served as tlie index of activity. The number of individuals active during any given trapping period was also im- portant. A certain proportion of the animals trapped were not marked, so it was necessary to correct for that by estimating the total num- ber active. n=lc+^c {la— lb) la a=traps containing animals/hour. i»= traps containing marked animals/hour. c=the individuals trapped with marks/ hour. n=the individuals active/trapping period (48 hr). 'Time Is e.xpressed in 24-hours military time: 1200 = noon and 2400 = midnight. 'The t test was used to test the hypothesis that the difference between population means of males and females was equal to zero (P<.05). "Analysis of variance was used to test tlie hypothesis that the ratio of males and females did not change for each of the months between February and August (P<.05). 'Analysis of variance was used to test the hypothesis that the ratio of males and females did not change for each hour they were collected during the day (P<.05). 28 Bkicham Younc UNiviaisiTY Science Bulletin -ssiuNns- -J.39Nn9- o > ■ -asmNns- -i3Sf4nS- lO * ro CM — o>oo t^ to m* row— o oj «/ a a 5 a. ^ a 1 3 'S v> ffl (0 UJ vf^ u. — ■" J3 <■ M . = g CM — u c o CM •s-s-i eg !^^- o CM 7?U 00 III -~ (0 O oj 3 ♦ 00 ^=1 o 2 •■" C K M CM O CD U m oo rig- (0 £ 3 - ■s -^ •= * c 9 » cu CM" — ill CsJ CM |§-Q 6U. 6 O) - SJ5 CD ^ (UT3 UJ O TJ C >^^ — « U) u. -^ ^ * ^sls *" 'O £.g.? CM - £ E S Biological Series, Vol. 6, No. 3, March, 1965 29 lOlOWiOiOiOio.. ooh.(Oio^tO(M!Gio -BsiaNns -i3SNnS o -3SI«NnS- iBSNns- CVJ right ordina line is subsu ngimembris; O "" a> .S 00 CD = J 3 a: i ^-5 -• (0 < -3 a /• s s-g^l ^ > CVl CM — rt ,^ -a CM •S^ § r ?^ O *- 2 CM "^ '"■ 5 s 00 cle); 1 bottom tempe > (0 o -3 o ^ c « ♦ 5 00 r 2 '" f ■ ^ a: C £ M 0 a,— > O < C S U of > C.2t3 00 — 1 6 * (0 * CP, line lerria leuci ca in 5 lUOUS ys m hilus CM" — mammals op contir Dipodom ospermop * CM V) '^ o ^^-5 CM CM Efc E< ^ CO = §iS ir £ M — < ■^^"S-S <0 S t ;S 3 3^ ^ S S E !^ s- a. o tSi E S g ^ ?? ii iJ^ jO^ row— o- -a = C^-2 M^^ cvj £ §^2 * cw"^ £i) CM s ^ s CM CM 5 S*^ O ..s,i CM ^i| n -a .i2 OD ^.§-•5 SQ g (0 "" S| to :Ji t to a-^ s CM — >- o^iJ < "? "J g 05 IN m^ s^ 00 C 0) 3 0 Oi "1 ii-^ (0 * CD g-K o> o ° -H g-T3 ^ " o » CM * ^ •- -s i CM oT H o = U"t^ CM lO ^ ^ J, CM .5 iM o ^ .S g^n. CM — is|| CM (0 1-::-a S — > < ^2 CM ^Sl1 ■~ ^ 1. r. i' O alp 00 sllj = 0* to to — o 32 BiticiiAM VouNc Univkrsity Science Bulletin — o o) 00 r^ (0 lo r^ lO (O ~ o> m ro — o — CU :^ ;§.:.- 2 y. S a _ c ~ o = o ^ o ^ IN i: ^ u Biological Series, Vol. 6, No. 3. Mabch, 1965 33 » u J, S^SSS2>t!22 = o>'- «oro-o 00 I-. V: rH o § (0 so S "!; t ill CM £ "a S lO « o = O CVJ Wr ~ -J 00 3 .12 s a: ~i <0 .5 S S O o o ^ ■M.5-° 12 Q -a ii g g — £ .a iJ ° 34 BitioiiAM YouNC University Science Bulletin .Vc -lasNns -38l8Nn6 -i3SNnS- J . - 8^ = 1-2 00 (O o CM fsJ * O ill D < l.'^-a OJ 5 s' = ^ 5 » o CM 3 ~" SB CSJ O Irs CM "5-2 2 GO ■i: .~-o ■SfS <£ * "r 2 0) "S-^ C. N -> 11^ o < ^ £ - ■g 3 S 5^ oo <0 * CD C ^ 2 S-5 C\J CM — Ch g fc 3 CJ u i fe 3 CVJ c .s ^ a o ■; = r^ CM " ^ -1 "a. 00 § ="=-1 00 s^5 1 (0 -J — .1 2 ^ < Vtles of sm e ( degrees ind bottom line is Amr CM :--.ti o 00 22. Di temper mperatu )m dot-d CVJCViCVJCVj'-^ — — ~~" Biological Series, Vol. 6, No. 3. March, 1965 35 lO lO lO « (O W ,rt -BSIUNOS- ^ i c £ "§ ■" (£ o ^ tit: -fi 3 ^ c „ CVJ o .5 if w ^laSNDS- -3sidNns- -lasNns- ti£ — *!2^ — 9 WOON- in li -^sidNns -13SNnS BSIdNnS i3SNnS h-tOIO^WCVJ — OOOON-tDlO^rOCM — — CVJ ~ a: < O 2 Biological Series, Vol. 6, No. 3, March, 1965 37 lOlOiOlOlOiOioiO,- '3SI)JNnS X 13SNnS asidNns o (0 M M M M O CM 00 M O 0) (0 * CsJ NtOm^rOCM— O 0>0)K- 00 (0 (M CM (M O _ CM — < f^<0 !G* rocM — 00)00 h-(om ^ rocM— o Biological Series, Vol. 6, No. 3, March, 1965 39 Si — ^ q> 00 h- (o «o » fo (\j £ lo -SSIdNHS -IBSNnS o 3smNns- i3SNnS- NjOiO^ !2MzOo>ooh- CM £2 O S'=3 CM ■'£ ^ DO (U s^ II U> O .2- * ^ Ji ■- to CM .. S = o z -9 n circle ) nd botto temperat o >: M <0 a 2 S O Cu 5 (0 =11 M 2 o a c ° CM — I,-- ° CM fc.';§ § CM """*:«■- O •2 o g CM ^.sl 0) |§s 1 o^S (0 to „ °-§ * CM F* Z CM 3 -> o g^s-^ 2 2 S 00 (0 40 Briciiam Young University Science Bulletin ^ E .5 S "2 "J CSJ = ^ "* o ■a- •C V, en O g;a to 1. a u> _l c- 5 3 r; ^ ^ -a = c CJ * ^ s CM CVJ CSJ £5 O — .2 CM 7?§ 00 (0 "S = C . «t 0) ~i = CM c c W J S E 3 __ — o -3 •=r „--^ 00 i i (0 "5 -iC * ._- c = c CM '. .5 * £ 5 CM 1 3 CM E = CM ^^ O e'^ CM ■■" -./' oo •^ .'^ 00 CM fei o "3 (0 -I 3 cT i -3 V fl * Q 1 00 e CM N- 0t)f»-<0lO^«Ocvl -o Biological Series, Vol. 6, No. 3, Mabch, 1965 41 Using this estimate and assuming that marked and unmarked animals were equally likely to be trapped, the values for ;i were com- puted and presented in Table 5. Following tlie estimation of the number of animals actually involved (;i) in determining the e.\tent of ac- tivity (-a), correlation coefficients were com- puted between them. There was a positive cor- relation (P<.05) \vith D. merriami (r=.924) but, no correlation with D. ordii (r=:.728). The values of r were transformed to z with the me- thod illustrated by Snedecor (1946) and the value of t was determined to evaluate density dependency of the two species. Neither D. mer- riami nor D. ordii appeared to be density de- pendent (P<.05). TTie frequency that individ- uals were active was measured by grouping them into several categories which could then be expressed in percentages (Table 6). Movement The distance between traps where an indi- vidual was captured was measured to determine how f;rr an animal moved during one night or a single trapping period. This was not intended to measure the actual range of movement, but only the distance between trapping stations traveled by individuals during a single night or trapping period. Dipodomys merriami - Table 7 summarizes the movement of D. merriami and relative num- bers of animals participating in each distance category'. Movement was primarily less than 45.7 m ( 1.50 ft ) since 85.8% did not exceed that distance during one night. In one trapping per- iod 80.0% moved less than 45.7 m (150 ft). The ma.ximum distance moved in one night and a single trapping period was 248.5 m (815 ft). Table 5. Corrected number of Dipodomys merriami and Dipodomys ordii individuals that were active during each trapping period in IF; a = traps containing animals/hour, fc = traps containing marked animals/hour, c=the individuals trapped with marks/hour, and n= corrected number of individuals which were active/ trapping period. Species Month 2a 2fc 2c n Dipodomys merriami Feb 23 23 16 16.00 Mar 59 43 23 29.23 Apr 47 45 23 23.97 May 80 66 21 24.67 Jun 73 45 18 24.90 Jul 136 91 39 51.90 Dipodomys ordii Feb 5 5 4 4.00 Mar 35 23 16 21.48 Apr 88 69 19 23.10 May 74 56 16 19.89 Jun 59 26 6 9.36 Jul 78 49 21 28.81 Table 6. Summary of individual activity of Dipodomys merriami and Dipodomys ordii during a trapping period Period Activity Dipodomys merriami Total Percentage Dipodomys ordii Total Percentage Marked Captvired 1 night only/trapping period Both nights/trapping period 2 times in 1 night/trapping period 3 times in 1 night/trapping period 4 times in 1 night /trapping period 5 times in 1 night/trapping period 2 or more times in pm, not in AM/trapping period 2 or more times in am, not in PM/trapping period In PM only In AM only 63 62.4 28 46.0 38 37.6 33 54.0 50 49.5 46 75.4 18 17.8 21 34.4 7 6.9 10 9.9 2 2.0 4 6.6 12 11.9 7 11.5 6 6.0 6 9.8 20 19.8 5 8.2 18 17.8 11 18.0 "AH individuals which were marked from February to July are included in this table. 42 Bi(J(;ham Voi.N<; Univehmtv Science Bulletin During P'ebniary 100*:^ moved less than 22.8 m (75 ft), but as the season progressed this percentage decreased until June, when it raised again. In March M.y/c moved 0 - 22.8 m (75 ft), in .\pril 80.0''*, in May 46.1%, in June 66.7%, and in July 77..3%. This species mo\ed farthest in Ma\-; 46.1% mo\'ed between 0 and 22.8 m (75 ft), 23.1% between 22.8 m (75 ft) and 61.0 m (2(X) ft), 1.5.4% bet^veen 61.0 m (200 ft) and 152.4 m (500 ft), and 23.1% between 152.4 m (500 ft) iind 4.57.3 m ( 1,500 ft). A total of 42.9% moved in excess of 91.5 m (.300 ft) during a full moon and 57.1% during a partial moon. No ex- cessive movement was recorded wlien tliere was no moon, but this may have been coincidental with months when movement was much re- duced for other reasons. Dipodomijs orclii - A summary of movement and relative numbers of animals participating in each distance categoiy is presented in Table 7. The majority (79.6%) moved less tlian 45.7 m ( 150 ft) during one night, whereas 75.1% moved this distance in two nights ( one trapping period ) . The ma.ximum distance one animal moved was 388.7 (1275 ft) in one night and 4.57.3 m (1500 ft) in a single trapping period. All animals moved less than 22.8 m in Feb- ruary, but as the season progressed this percent- age decreased until May when it began to rise again. In March 80.0% moved less than 22.8 m (75 ft), in April 64.3%, in May 18.2%, in June .50.0%, and in July 74.0%. This species mosed farthest in May; 18.2% movetl between 0 and 22.8 m (75 ft)', 27..3% between 22.9 m (75 ft) and 61.0 m (200 ft), 36.4% between 61.1 m (200 ft) and 152.4 m (.5(X) ft), and 27..3% be- tween 152.5 m (.500 ft) and 457.3 m (1500 ft). None moved more than 61.0 m (200 ft) in June or July. Of those that moved in excess of 91.5 m (300 ft), 71.4% did so when the mfK)n was full and 28.6% when it was only partially full. No excessive movement oc-curred when there was no moon, probably because this was coincidental with months when movement was reduced for other reasons. Spatial Distribution Distribution of U. incnUimi and D. ordii within the grid (IF) was investigated from the point of view of trap utilization and the use of available space. Table 8 presents the percentage of traps that were visited from one to five times in one night and one to six times in a trapping period of tvvo nights. Table 9 presents the per- centage of the traps that were visited from one to five consecutive hours. Tliese percentages were derived from an analysis of all 72 traps. It Table 7. Summary of movement during a single night and a single trapping period (48 hr) for Di})odomijs mcr- riami and Dipodomys ordii, which were trapped two or more times. Percentage of animals that moved in One night Two nights meters merriami ordii merriami ordii 0- 22.8 65.2 53.6 58.3 42.7 22.9- 45.7 20.6 26.0 21.7 32.4 45.8- 68.6 6.5 7.8 3.3 2.8 68.7- 91.5 1.1 3.1 3.3 8.3 91.6-114.3 3.3 1.6 5.0 5.5 114.4-137.2 0.0 1.6 1.7 2.8 137.3-160.1 0.0 3.1 0.0 0.0 160.2 - 182.9 1.1 0.0 1.7 0.0 183.0 - 274.4 2.2 1.6 5.0 0.0 274.5 - 457.3 1.6 5.5 Total 16 14 12 10 Talile 8. Percentage of traps that were visited by Dipodoiiii/x tncrritniii and Dipodoniijs ordii 1-6 tijne.s during one night, and 1-6 times in a single trapping period (48 lir) Month One night Two nights 1 2 3 4 5 1 2 3 4 5 6 Feb 26 03 40 07 04 Mar 33 13 04 72 33 18 04 03 01 Apr 53 28 19 10 03 65 42 29 24 17 11 May 54 29 15 06 06 83 51 33 22 08 07 lun 49 28 17 13 07 68 47 35 24 15 11 Jul 78 53 35 13 04 83 72 56 46 29 26 Biological Series, Vol. 6, No. 3. March, 1965 43 Table 9. Percentage of traps that were visited by Dipodomijs merriami and Dipodomijs ordii on 1 - 5 consecutive hours of one night. Month Hours of Consecutive Trapping 1 2 3 4 5 Feb 40 Mar 72 08 Apr May lun 65 83 68 14 25 43 01 06 08 01 01 01 04 Jul 83 39 04 01 01 is apparent from Table 8 that the percentage of traps visited twice during a single night was rather low (3-53). In two nights the percentage increased considerably (7 - 72). The percentage of the traps that were visited twice on consecu- tive hours was low (8 - 43 ) . A rapid percentage decrease was noted as the number of \'isits was increased. It seemed best to demonstrate spatial distri- bution by using the month of July, in which the largest number of captures was recorded. AU other months were similar-. The captures plotted on a grid revealed no consistent pattern of dis- tribution (Fig. 29). The distribution changed from one hour to the next. There were areas which seemed to have more activity than others, but these same areas frequently had less activity on the following night. Even at times when ac- tivit\' was highest large areas had no captures during a given hour, but made several captures 0 0 ■ M 0 M . . . 0 M 0 0 M . . M M DOOM M M • M 0 Figure 29. Distribution of captures in IF during a single trapping period (48 hours) in July, 1961; dots are that were empty; O's are Dipodomys ordii; and M's are Dipodomijs merriami. traps 44 Bkioham Young Univehsity Science Buixetin during the next hour. Distribution concentrations ditl not repeat themselves between consecutive nights. Discussion of Daily Activity Diel cycles have been studied for several species of small mammals in North .\merica: Bartholomew and Cade (1957), Belmey (1936), Calhoun (1945), Chabreck (1962)', Foster (1961), Hansen (1957), John.son (1926), Orr (1959), Pearson (1959), Reynolds (1960), Spencer (1941), and others. The.sc studies were frequently conducted under controlled condi- tions using small numbers of animals and some records were made of the activity of individual animals only. Data from these reports are valu- able in interpreting field data and serve well in understanding the reaction of the population to its environment. Calhoun (1952) stated that as the density of rats increases there is an increase in complexity and frequency of behavior ad- justments. If this is so, an increase in activity could effect similar results on behavior adjust- ments as would an increase in population densitv'. Increased activity would also enhance the pos- sible physical contact of individuals, resulting in greater competitive stresses. These stresses could, in turn, alter phenomena such as long- evity and home range. With the apptirent in- fluence that activity has on trapping results, it must be considered when interpreting certain population parameters. Competition among Species Staggering periods of activity' often allows two or more species to occupy the same habitat- niche. Tliis seemed to be the situation at 5CP where A. leucurus occupied the area during the day that D. merriami, D. microps, and P. hii^i- membris occupied during the night (Fig. 16-28). Although not nearly as evident D. mcnianii and D. ordii also staggered their daily cycles with those of D. microps (Fig. 15). The largest peak in activity of D. microps was on the fifth hour when D. merriami and D. orris switchetl from entirely males in March to little difference from April to August. This jx'riod (April-Aug- ust) agrees with the results of Duke (1957), who stated that reprcxluction in Utaii Pero'^na- thus was from April to July. The results of our studies indicate that the se.\ ratio for this species was even after the females had emerged from winter hibernation. No females were captured in February, and it is assumed that the large pro- portion of males was due to tiieir early emer- gence from winter hibernation. Hall (194B) assumed this species to hibernate and later Bar- tholomew and C^ade ( 1957 ) successfully demon- strated both hibernation and aestivation. Since no c-orrelation was evident between environ- mental stresses and switches in se.\ ratios for any of the species studied, it was concluded that no explanation is readily available for the abrupt decrease of activity of one or the other sex, re- sulted in some hourlv fluctuations. Environment in Relation to .Vctivity of Different Species Seasonal changes in trapping results seem to be correlated with the intensity of individual activity in the case of D. ordii, but not witli D. merriami. Movement was also demonstrated to change as the season progressed, and was most extensive in June. The percentages of animals that were captured on consecutive hours during one night also changed and were highest dur- ing Julv. The percentages of animals that were captiired on consecutive nights were greatest in July. Animals apparently moved farther in June, but inore were out two or more times in a shorter range in July. Seasonal variations can generally be explained in terms of changing population di-nsities for most species. However, as was j')<)inted out in the case of D. iiicnunui and D. onlii. variations might be at least par- tially due to changes in activity. Hibernation and aestivation also influences seasonal varia- tions in trapping activity, as v\as pointed out in the case of P. loiiiiinicnihris: flight appeared to be the environmental factor primarily responsible for triggering activi- ty. Figures Hi- 28 demonstrate that A. Iciinini'i ceased to be active anil D, iiicnuiiiti. D. oidii. D. niicrop.s. and P. /()ngiHit'»i/;rK initiated their activity at sunset. From February to June there was a difference between simset and sun- rise of 8.0 to 5.5 hours, respectively. Regardless of this 5.2 hour variation from Februarv' to June, activity was initiated at sunset or soon after throughout the time ol this stndv. I'.nvironmental factors such as temperatures, moonlight, wind, and light intermittent rains had little influence on dailv trapping results of D. orilii and D. merriami. in one case of D. ordii a rather sharp decrease in numbers was shown to be a result of decreased activity on the part of females. Other cases were noted in which changes in the activity of one sex resulted in hourly and/or dailv fluctuations. Hourly fluctua- tions of P. loui^imcmhris may be partially ex- plained in terms of their negative response to rains and changes in moonlight. Bartholomew and Cade (1957) demonstrated that P. lonoi- mcmbris hibernated within 24 hours when f(K)d was not available, but if it were available only a fevs- hibernated in several days. HOME RANGE The concept of home range and other meth- ods of measuring animal movement have been considered as important behavior chiirarcter- istics of mammals for many years. Some inter- esting studies were made by Brant (1962), Burt (1940), Calhoun and Casby (19.58), Dice and Clark (1953), Harrison (1958), Hayne (1949b), Jackson and Strecker (1962), Jorgcn- sen and Tanner (196.3), Mohr and Stunipf (1964), Spencer and Davis ( 19.50), Stumpf and .Mohr (1962). Tanaka, Sugivama and Teramuro (19.58), Tinkle, .McCregor and Sumner (1962), and others. Some of the advantages and disad- vantages inherent in tiie methods used to deter- mine home range have been discussed by Hayne (1949b), Calhoun and Ca.sby (1958), and Jor- gensen and Tanner (1963). The home range concept must include relative intensity of usage if it is to furnish data useful in analyzing popu- lation data. Uniform usage, regardless of the shape of the area, is not realistic and must be reevaluated if specific interactions are consid- ered. .\ rotnul home range is e(jually as unreal- istic but provides the most convenient data that can be applied to population density determina- tions. .\notIn'r aspect ol home range tluit is fre- (luentlv negleeted is the time interval reipiired to gather tlie field data. It is becoming increa.s- inglv evident as we continue to work with small mammal interactions that this factor will have to be evalu.ited more completely. Biological Series, Vol. 6, No. 3. Mabch, 1965 47 Home-range data have been used by us in several ways. They were used in our density determinations which were in turn used to eval- uate the effects plant communities have on small mammal distribution. They were also c-onsidered in evaluating spatial interactions of individuals Home range or more precisely "range of move- ment" was used to measure the effects of nu- clear weajjons testing on small mammals by White and Allred (1961). Methods Home ranges were measured in ten grids which were situated in different plant associa- tions at the test site. The trapping design of these grids is described bv Allred, Beck and Jor- gensen (1963a). Since several grids had small mammal species in common, home ranges were measured several times for certain species. In other cases the home range of a given species was measured in only one grid. Vegetation analyses were made for most of the grids and these are summarized in Table 10. The grids and the species measured in each are sum- marized in Table 11. These plant analyses were taken with the method described by Jorgensen (1963). Table 10. Percentage of ground cover and composition of trapping grids at the test site. Plant Species Grids " 12Ai» 12E>' lOD 6A 5A 5E 4A IF" JA TA Percentage ground cover X X 25.4 21.0 11.4 11.9 19.6 X 17.4 31.0 Artemisia spinescens 0.9 3.0 0.5 3.4 Artemisia tridentata X X 67.5 Atriplex canescens 2.7 6.4 Atriplex conf ert if olia 60.7 0.3 Bromus rubeiu X Cercocarpus ledifolius X X Chaenactis stevioides X Coleogyne ramosissima X X 64.2 30.0 Cowania stansburiaiia X X Dalea polyadenia 3.3 7.0 1.2 Ephedra nevadensis 2.8 6.3 15.2 7.9 Ephedra viridis X X Eriogonum sp. X Eurotia latuita 0.1 10.6 2.7 15.1 1.9 Franseria dumosa 20.2 9.9 Grayia spinosa 24.2 7.9 17.4 53,8 9.9 1.6 Hymenoclea salsola 2.0 9.5 0.4 Junipenis osteosperma X X Kochia amcricana 25.7 Larrea divaricata 44.9 5.1 Lycium andersonii 2.1 7.9 8.2 15.4 9.5 Lycium pallidum 60.0 9.8 Mirabilis pudica 0.9 X Oryzopsis hymcnoidcs 2.4 0.3 3.7 Firms vxonophylla X X Quercus gamhelii X X Salsola kali X Sitanion lianscmi 0.5 0.4 2.5 Stipa comata X X 1.8 Tetradymia axillaris 0.5 1.3 Tetradymia glabrata 0.3 Stipa speciosa 20.2 Haplopappus cooperi 0.3 0.1 Chrysothaninus viscidiflorus 2.8 0.2 Krameria parvifolia 0.1 Dalea frcinuntii 1.3 Lcpiiliuiii frcmontii 0.6 Stanleya pinnata 0.7 ^Refer to Allred, Beck and Jorgensen (1963b) for location of each grid. 12A - Pinyon-Juniper (disturbed by testing), 12E - Pinyon-Juniper, lOD - Coleogyne, 6A - Atriple.x-Kochia, 5A - Larrea-Franseria, 5E - Larrrea- Frnnseria (Lycium }mlUdum association), 4A - Grayia-Lycium, IF - Salsola (disturbed by testing), JA - Larrea- Fran.seria (mixed plant association), TA - Coleogyne (Artemisia tridentata association). ''Vegatation imalysis data are not available for these grids. 48 Bhickam ^'ounc University Science Bulletin (X, a. a, E >^ L. 6 2 Q o a, u Q E ^1 cu.g .2 e OQ E X X XXX oi in (N in ;D — 1 CO —I 03 —1 t-5 O! -■ ^ *" -i -• , ^^ - -^ - w^ - v., - ,^ ™, ,„ 00^ cocjioiio-ico o^iricot-:--i^ot-:'"^'°°oi '"-^'-'oi <»g5' _, Ol 00 t^ S t^ CO CO O) CO 00 in , CD in o in — ■^^0„— loico — ^^oq ,.,co_,r^ cot--Q : J2 ^ J; K s Q CO ^ — ' ^ ^ ^ ^ (^ rt ^ :< « Q^ :a s «°l V *— * "a, ■c CI < « 2 c fa .g in ■B 5i s ^ 1 >, X S S e J &i a .S T^ .S B o >> ^ TSna O 5 ^-^ 1 1 "o ^ < _c .C ii m" &, s a o d ^ S? C/5 n _3 "Is a s , C o C J; rH PX, [I, <; 2 52 BiiioiA.M Young Univeh.sity Science Bulletin -Table 13. T)i. Iiomc ranges of smull mammals among thu plant communities. Average Ai •ea for each Species (Ares)-^ Grid and Biotic Community Amm leu Dip mer Dip mic Dip ord Ony tor t' Ion Prg par Per man Per tru IF Salsola 168 (4.20) 133 (3.33) 4A Crayia-Lycium 304 (7.60) 516 (12.90) 249 (6.23) 127 (3.18) 5A Larrca-Franseria 384 (9.60) 269 (6.73) 208 (5.20) 242 (6.05) 5E Larrea-Fnuiscria 196 (4.90) 246 (6.15) 107 (2.68) 145 (3.63) 203 (5.08) 6A Atriple.\-Kochia 157 (3.93) lOD Coleogyne 779 ( 19.48 ) 148 (3.70) 209 (5.23) 675 (16.88) 193 (4.83) 601 (15.03) 12A Pinyon-Juniper 112 (2.80) 47 (1.18) 12E Pinyon-Juniper 76 (1.90) 159 (3.98) 108 (2.70) JA Larrea-Franseria 324 (8.10) 161 (4.03) 131 (3.28) 533 (13.33) 136 (3.40) 50 (1.25) TA Coleogyne 467 (11.68) 462 (11.55) 740 (18.50) 85 (2.13) 108 (2.70) 221 (5.53) LSD. « 268 n.s." n.s. n.c." n.s. n.s. n.s. n.c. n.s. n.c. LSD. „, 433 n.s. n.s. n.C. n.s. n.s. n.s. n.c. n.s. n.c. »Not significant. ■■Not computed because of insufficient data. 'Amm leu - Ammvupennophilu.t leucunm. Dip mer - Dipodomys mcniami. Dip mic - Dipodomys microps. Dip ord - Dipodomys ordii. Ony tor - Onychomys torridus, Prg for - Perognathus formosus, Prg Ion - Perognathus loiigimembris, Prg par - Pcrogiutthus parvus, Per man - Peromyscus maniculatus. Per tru - Pewmyscus truei. Numbers in parentheses are areas in acres. Table 14. Differences in the average home ranges of male and female small mammals. Average . Area for each Species (Ares)" Species Male Female Difference Ammospermophilus leucurus 504 (12.60) 477 (11.93) 27 (0.68) Dipodomys mcrriami 378 (9.45) 185 (4.63) 193 (4.83) Dipodomys microps 491 (12.28) 360 (9.00) 131 (3.28) Dipodomys ordii 85 (2.13) 180 (4.50) -95 (-2.38) Onycliomys torridus 676 (16.90) 622 (15.55) 54 (1.35) Perognathus formosus 243 ( 6.08 ) 82 (2.05) 161 (4,03) Perognathus loiigimcmhris 196 (4.90) 104 (2.60) 92 (2.30) Perogruithus parvus 92 (2.30) 92 (2.30) 0 (0.0) Peromyscus municuUitus 340 (8.50) 206 (5.15) 134 (3.35) Peromyscus truei 87 (2.18) 68 (1.70) 19 (0.48) ^Numlx.rs in parentheses are are.ts in acres. To provide an estimate of their intraspecific interactions, the nunilxr of recapture centers that would fit on a linear transect through tlie computed radius of respective home ranges was determined. This determination was made by measuring the distance between each recapture center and its nearest neighbor. Measurements were made betvveen male and male, female and female, and male and female. After these mea- surements had been taken, the average was computed and divided into the recapture radius to determine tiie numbers of recapture centers that would be expected to occur within any given individuals rec-apture radius. Tliis pro- vided a tx>ntrast of the distance between re- capture centers of nearest neiglibors and recap- ture radii. The results of this analysis are pre- sented in Table 16. Tile most apparent obserxation that can be made from this analysis is that the number of recapture c-enters per recapture radius increases as the density- of recapture centers increiuses on each grid. These observations suggest that the size of home range is not entirely dependent on the densit\' of organisms measured, thus adding Biological Series, Vol. 6, No. 3, Mabch, 1965 53 Table 15. Summary of the grid size adjustment, resulting from marginal extensions by the distance of the recap- ture radii. Recapture Adjusted Species St udy'' Radii (m)-- Grid Ai rea Percent; ige P<.05 (Ares: ]•= Increase Male Female Male Female Male Female AmmospeTTiwphilus leucurus 4A 114 81 2304 1713 269 74 (374) (266) (57.6) (42.8) 5A d 109 (358) — 2209 (55.2) — 254 5E 62 (203) — 1413 (35.3) — 126 — lOD 145 170 2937 3504 370 461 (476) (558) (73.4) (87.6) JA 113 90 2284 1866 266 199 (371) (295) (57.1) (46.7) TA 132 113 2662 2284 326 266 (433) (371) (66.6) (57.1) Dipodomys merriami IF 74 73 1600 1584 156 153 (243) (239) (40.0) (39.6) 4A 175 50 3624 1259 480 98 (574) (164) (90.6) (31.5) 5A 116 62 2342 1413 275 126 (380) (203) (58.6) (35.3) 5E 105 70 1274 1536 104 146 (344) (230) (31.9) (38.4) lOD 66 (216) — 1474 (36.9) — 136 — JA 85 55 1780 1310 185 109 (279) (180) (44.5) (32.8) TA 114 126 2304 2540 269 307 (374) (413) (57.6) (63.5) Dipodomys microps 4A 100 78 2043 1664 218 166 (328) (256) (51.1) (41.6) 5E 61 56 1398 1324 124 112 (200) (184) (55.0) (33.1) 6A 78 63 1664 1428 166 228 (256) (207) (41,6) (35.7) lOD 87 77 1814 1648 190 264 (285) (253) (45.4) (41.2) JA 66 63 1474 1428 136 228 (216) (207) (36.9) (35.7) TA — 35 (115) — 1036 (25.9) — 66 Dipodomys ordii IF 52 76 1267 1632 103 161 (171) (249) (31.7) (40.8) Onychomys torridus lOD 133 160 2683 3271 330 424 (436) (525) (67.1) (81.8) JA — 123 (403) — 2480 (62.0) — 297 TA 169 139 3481 2509 457 350 (554) (456) (87.0) (62.7) Perognathus fonnosus 5A 108 41 2190 1556 251 78 (354) (134) (54,8) (38.9) 5E 85 46 1780 1183 185 89 (279) (151) (44.5) (29.6) JA 67 65 1490 1459 138 133 (220) (213) (37.3) (36,5) Ferognathus longimemhris 4A 80 41 1697 1115 171 78 (262) (134) (42.4) (27.9) 5A 101 74 2061 1600 230 156 (331) (243) (51.5) (40.0) 5E 80 82 2061 1730 171 177 (262) (269) (51.5) (43.3) lOD 102 46 2079 1183 233 89 (335) (151) (52,0) (29.6) 54 Bkicham Young Univehsity Science Bulletin JA 43 (141) 37 (121) 1142 (28.6) 1062 (26.6) 83 70 TA 52 (171) 52 (171) 1267 (31.7) 1267 (31.7) 103 103 Perufi^iMlhus jmrvus 12E 47 (l.'>4) — 624 (15.6) — 121 — TA 61 (200) 56 (184) 1398 (35.0) 1324 (33.1) 124 112 Pcromy.scus tnuuiculatus too 173 (567) 94 (308) 3576 (89.4) 1936 (48.4) 473 210 12A 60 (197) 60 ( 197) 838 (21.0) 838 (21.0) 197 197 12E 78 (256) 64 (210) 955 (23.9) 885 (22.1) 239 214 TA 65 (213) 104 (341) 1459 (36.5) 2116 (52.9) 133 239 Pcromyscus trtici 12A 47 (154) 37 (121) 624 (15.6) 591 (14.8) 121 109 12E 63 (207) 55 (180) 873 (21.8) 780 (19.5) 209 176 "IF - Salsola, 4A - Grayia -Lvcium, 5A - Larrea-Franseria, 5E - Larrea-Franseria, 6A - ■ Atriplex-Kochia, lOD - Coleogyiic, 12A - Pinvon-Juniper, 12E - Pinyon -Juniper, JA - Larrea-Franseria, TA - Coleogyne. '■Numbers in parentheses are distances in feet. 'Numbers in parenfhe.se.s iire areas in acres. "'None was collected three or more times in at least two stations. Table 16. Number of recapture centers along the recapture radii of home ranges. Average Distance (m) Recapti ore between Centers per Species Study^ Nearest Neighbors Recapture Radii Male" Female Female WAc Female to to to to to Male Female MiUe Male Female Ammospermophilui Icucurus JA 37.08 (122) 38.56 (126) 41.87 (137) 3.07 2.10 TA 48.68 (160) 56.93 (187) 40.28 (132) 2.71 1.98 Dipoclomyx mcrrumii IF 14.96 (49) 16.72 (55) 13.51 (44) 4.94 4.36 5A 31.00 (102) 22.71 (74) 33.52 (110) 3.74 2.73 5E 42.86 (141) 52.70 (173) 43.21 (142) 2.44 1.32 TA 53.07 (174) 67.10 (220) 42.42 ( 139) 2.14 1.87 Dipodomys mkropi 101) 15.94 (52) 17.43 (57) 16,52 (54) 5.45 4.41 6A 20.61 (68) 28.75 (94) 22.23 (73) 3.87 2.19 JA 28.70 (94) 28.88 (95) 31.02 (102) 2.29 1.77 5E 28.50 (93) 63.02 (207) 36.06 (118) 2.14 .89 4A 46.86 (154) 39.34 (129) 41.93 (138) 2.13 1.98 DifHtdomys ordii IF 48.89 ( 160) 37.30 (122) 53.06 (174) 1.06 2.03 Pcroj'niithus /oriiio.Mi.y JA 24.13 (79) 36.69 (120) 24.71 (81) 2.77 1.79 Pcroj^iiutliiis longinicml>h.s JA 32.86 (108) 28.14 (92) 23.27 (76) 1.30 1.31 JioLOcicAL Series, Vol. 6, No. .3. M.irch, 1965 55 4A 33.51 33.26 32.07 2.39 1.23 (110) (109) (105) 5E 34.25 55.10 28.15 2.33 1.49 (112) (181) (92) 5A 41.97 43.92 40.03 2.41 1.68 (138) (144) (131) TA 36.38 36.73 26.95 1.43 1.34 (119) (120) (88) 12A 19.92 23.74 17.44 3.01 2.53 (65) (78) (57) 12E 28.79 51.24 32.04 2.71 2.69 (94) (168) (105) Peromyscus maniculatus "IF - Salsola, 4A - Grayia-Lycium, 5A - Larrea-Franseria, 5E - Larrea-Franseria, 6A - Atriple.\-Kochia, lOD Coleogyne, 12A - Pinyon-Juniper, 12E - Pinyon-Juniper, J A - Larrea-Franseria, TA - Coleog)Tie. •■Numbers in parentheses are distances in feet. Dipodomys merriami Male Dipodomys merriomi Female Male-I, Female— — Figure 30. Recaptvire centers and home ranges of Dipodomi/s mcrrian 56 BiiicHAM YouNC UsrvERsiTV Science Bulletin support to our c-ontention that competition for spiice among desert species of small mammals is relieved somewhat by their behavior. Discussion of Home Range Home range was considered from the {X)int of view of where individual animals were cap- tured and recaptured within grids with station- ar)' trapping stations. No effort was made to move the traps to other locations or to alter the baiting procedure from one month to the next. It is possible, therefore, that some "trap-hap- piness" mav ha\e cle\'el()[K"d. But, since the grids were trapped for onJv three days each month, it is doubtful that the habit would have been easily detected. Oipodomys microps Mole-», Female Dlpodomys microps Figure 31. Retapturc centers antl home ranges of Dipodomys microps. Biological Series. Vol. 6, No. 3. March, 1965 57 Another problem that arises from this tvpe of an approach is the time inter\als in which the data were actually gathered. Using the den- sity probabilitv- method of home range determi- nation over a long period of time would not allow detection of small changes in the range. For this reason the home ranges could actually be smaller at anv particular shorter time interval than our results indicate. \Ye attempted to ad- just for this by excluding those observations that fell outside what would be e.xpected (P<.05). -Although home range for an animal is cer- tainly subject to change from environmental stresses, only population density and trap density have been con\incingIv shown to be important factors. Such factors as se.xual activity, location. Perognolhus longimembri Perognolhus longimembns 5E Perognothus longimembns ** Figure 32. Recapture eentcr.s and home range.s of Pcrogriathus longimcmbris. 58 Bhicham VoiNc; University Science Bulletin wintering activity, etc. would likely ha\e an in- tluence on the animals' wandering habits. Our data indicate that although short wanderings mav have occurred, extensive wandering was rather rare and was not included in the analyses. Rather than resulting in a change of the actual center of the home range, it is more likel\ that the extent of their wanderings would incrciise. causing the home range to increase. It could he argued that computing home range over such a long period of time would increase home range, and this would certainly be true if the actual center were to change. But if only the range were to change, a long time period would do no more than measure the largest movement. We consider our data to represent the largest home range that would be expected and that any shorter time period would yield data showing home ranges e(|ual to or less than ours. For the purpose we have used home range ( cxnnputa- tion of small mammal densities) and jxjssible intraspecific interaction, this seemed to be ade- Ammospermophilus leucurus ^^ Ammospermophiljs leucurus JA Psrognathus formosus Mole Dipodomys ordii Female - Mala -4, Femole— -» Figure .3.3. Recapture centcr.s aiul home ranges of Ammospcrmophilus leucurus, Pcrognuthus formosus, and Di- podonxijs ordii. Biological Series, Vol. 6, No. 3. March, 1965 59 Peromyscus maniculatus 12 E Peromyscus maniculatus I2A Ma\e Female Male—*, Female — ► Figure 34. Recaphire centers and home ranges of Peromyscus maniculatus. Where only one recapture radius is presented ( 12A ) , both sexes had the same radius. quate. We must state, however, that if one is interested in other factors such as gene flow within the population, a short time measurement during the breeding season would likely yield the most useful data. Another factor which influences home range data is the margins of the grids. In this case the margins have the effect of limiting the recapture radii, causing the average home range to appear smaller. When home ranges are as large as tliey were generallv found to be during our work, it is difficult to assess the influence the margins may have on the average home range. All of the recaptures were included in our analyses, except for those excluded for reasons discussed in the methods; consequently, the a\'erage home ranges may be computed somewhat smaller than they actually are. The influence of the border on home ranges has the effect of being distance dependent. As the recapture radii distances increase, the border of the grid becomes more of a factor, while smaller recapture radii are influenced less by this border. In this sense it is probable that large computed home ranges are actually underesti- mated more than those wliich are smaller. Al- though the home ranges discussed in this report may at first appear large, if one considers all the factors contriljuting to the calculated estimates, it seems conceivable that they are underesti- mated rather than overestimated. One may wish to challenge these conclusions on the basis of short-term trapping results, but this is justifiable only if the short-term occurs during the time the animals have their longest ranges. Some observations resulting from the analyses of home range are of interest in terms of be- havior. Males generally range farther than the females, although tliis is not always true for individuals (Tables 12 and 14). The variation during the time of this study was rather high and would be expected to remain high when the data are gathered on a long-term basis. Note that though rather wide differences are observed between studies (Table 13), they were signifi- cant (P<.05) only in the case of A. leuciirus, and in this case the samples were questionably low. Interaction among species and individuals of the same species is sometimes thought to be rather specific, to the point of mutually exclud- ing some species and indi\'iduals while establish- ing discrete territories. Daily activity demon- strated that this interaction may not be nearly as competitive as is sometimes thought. Home range also indicated that competition is not so specific in establishing territoriality in the classic 60 Bkicham Young Univebsity Science Bulletin sense. In fact, as many as 5.45 average distances between the recapture centers of nearest neigh- bors may be found along one recapture radius (Table 16), thus allowing for tremendous inter- action in space. One must keep in mind the time interval in which these studies were made, for the longer the time the greater the number of recapture centers and the shorter the distance between them. This procedure, though used to illustrate interaction, would tend to overestimate the specific interaction at a given time. The extent of ON'erestiniation could not be determined from our work since it did cover a long time span, but it does illustrate that considerable interaction is present at all times. This interaction is thought to be such that it would not lead to the mutual exclusion of neighboring small mammals from a specific area. SPECIES DISTRIBUTION In keeping with one of our primary objectives at the Nevada Test Site, seasonal distribution of the small mammals and their distribution among the plant communities were investigated. This has been discussed, in part, bv Allred, Beck and Jorgensen (1963a), Murdock (1961), and Allred and Beck ( 1963 ) , but their work was focused essentially on the readily identifiable plant com- munities and the small mammals collected from within them. Similar studies were made bv Hardy (1945), Burt (1934), and Hall (1946) in other locaUties. The section of this paper entitled "Acc-ounts of the S{>ecies" briefly listed the biotic c-ommun- ities occupied by the mammals. The present section will deal with two aspects of distribu- tion— namely, the species distribution in the ecotone areas betvveen major biotic communi- ties and seasonal distribution within the estab- lished grids. The importance of plant species or complexes of plant species on small mammal distribution will also be discussed. Methods The trapping design and procedures for operating the ten grids as well as the arrange- ment and operation of the 136 transects have been described previously. The density of small mammals in the grids was computed with the methods described by Hayne ( 1949a ) . The margins of the grids were expanded to include the .95 probability radius of a recapture from the estimated activity cen- ter. The expanded grid was used for the density estimate. Densities were estimated each month, based on a three-day trapping period. Methods for computing densities when kill trapping techniques are used have been dis- cussed bv Leslie and Da\is (1939), DeLurv (1947), Havne (1949a). Moran (1951), Zippin (1956), and Calhoun and Casby (1958). Per- haps the most difficult problem encountered in estimating populations is whether or not all animals are equally at risk. In most cases it is assumed thev are, but Calhoun and Casby (1958) recognized the difficult)' of this assump- tion and attempted to correct for home-range centers which were apparently different dis- tances from the trap lines. We simply used the recapture radii com- puted for each species in the \arious biotic com- munities to extend the trapped area, thus ex- panding the size of the area bv the distance of their recapture radii on all four sides. For exam- ple, each of our 136 transects enclosed 39.6 ares (.99 acres), but to estimate the number of D. merriami it had to be expanded so as to include the total area apparently trapped. If the tran- sect (5CX) were considered to be in a Larrea- Franseria communit}', the recapture radii for D. merriami in 5A ( Larrea-Franseria, Table 13) was used to expand the actual area trapped to 421.6 ares (10.54 acres). This procedure was re- peated in every instance in which densit)' deter- minations were made. One might question why the recapture radii were not integrated in the densit}' estimate as described bv Calhoun and Casbv (1958). The principal reason was that the assumptions re- (juired for their procedures were not satisfied. In view of these difficulties it was felt it would be better to simply expand the trapping area rather than imply that these assumptions had been sat- isfied. The problem of estimating the population size was also replete with difficulties. Tlie prin- cipal problem centers, again, around whether or not the animals are ecjuallv at risk from day to day. If an animal used only fragments of its home range each day or if it were not trappable each day, the assumption that all are equally at risk is not valid. We ha\e no data concerning Biological Series, Vol. 6, No. 3. March, 1965 61 the first behavior problem, but our observations have led us to question the latter. When the species were pooled for analyses ( i.e., all the new marks on the first, second, and third days in each grid), there was no indication of variable trappability. When the individual trapping per- iods each month were considered, however, wide variation was apparent. On the strength of this, some adjustment of the technique proposed by Calhoun and Casby ( 1958 ) was made in our computation techniques. The population size was estimated with tlie following method: n=Ci/(l-c-/Ci) n= initial population size. c,= total captured on the two days when most were trapped. C2=total captured on the remaining day when fewest were trapped. This modification will obviously increase the slope of the regression curve and provide a more conservative estimate of the population. Due to the large fluctuations on individual trapping nights and since the second night frequently provided smaller estimates than the third, this adjustment seemed justifiable. The vegetation in the vicinity of each of the 136 transects was evaluated, but no quantitative data recorded. The predominant plant species along with those that were rather common in the vicinity of each transect were recorded. Results Spatial Distribution Trapping results from the transects are pre- sented in Table 17. These data were then grouped to examine the interactions of small mammals where they occur together. Correla- tion coefficients were computed for contrasting species to determine if any were significant (Table 18). From this table it is evident that for the most part there was no correlation in those cases where both species were present in the same area. The notable exceptions are A. leucurus vs. D. microps (r^.399) and A. leti- curus vs. P. longimembris (r=.331). The transects in which one species was pre- sent and another absent were examined (Table 19). Little can be observed from this table alone, but it does indicate which species were more universally distributed. For instance, P. longimemhris was absent from an average of only 17% of the transects, D. merriami from 27%, A. leucurus from 32%, D. microps from 39%, P. formosus from 49%, and O. torridus from 52%. Other data such as slope and soil texture con- cerning the transects were then examined to determine if some explanation was available that would assist our analvses. Tlie vegetation was the first environmental factor examined. A summarv of the vegetation and its relative abundance within each transect is presented in Table 20. A comparison of the small maiTunals and plant species can be seen from this table as the percentage of transects where both were present. Two items of particular interest may be ob- served from Table 20. Certain plant species ap- parently had little or no effect on small mammal distribution because of their ubiquitous na- ture or general absence at the time surveys were made. Atriplex confertifolia, Coleogijne ramoslssima, and Ephedra ncvadensis are exam- ples of those with a rather extensive distribution, while Chaenactis freniontii. Dalea pohjadenia, and Lepidium fremontii are examples of species which are generally not abundant. The second observation that may be made from this table is the apparent influence certain plant species have on small mammal distiibution. This does not necessarily indicate a causal effect and may re- sult entirely from secondary influences. Exam- ples of this type of interaction appear with Atriplex canescens, Franseria dumosa, and juni- perus osteosperma. To facilitate a graphic correlation betweeri small mammal abundance and relative abund- ance of predominant plant species, the predom- inant plant species were assigned the arbitrary value of two and the common species were as- signed the value of one. The transects were pooled into three categories, the selection of which was essentially arbitrary, but based on major breaks in the decrease in small mammal density. With this type of analysis any correla- tion would be visible graphically even though its interpretation would be somewhat limited. Only the principally important plant species (that repeatedly occurred in each transect) were included in these analyses. These results are pre- sented in Figures 35-40. Some general trends may be observed from an examination of Figures 35-40. For instance, it appears that A. leucurus decreases as Lijcium andersonii, Larrea divaricata, Franseria dumosa, and Grayia spinosa increase; and Eurotia lanata, Atriplex confertifolia, and Lijcium pallidum de- crease (Fig. 35). Dipodomys merriami tends to decrease as Larrea divaricata, Franseria dumosa, and Grayia spinosa decrease; and Eurotia lanata increases (Fig. 36). Bricham Vounc Univehsity Science Bulletin a, a. o^S. 15 S 3 ft- 6 a, 3 Is is Q E •a 3 S2 ' T O ■q- — • in 05— 050 OOt- t»-tM OOO 0> ^ yf o a> I 05 CO m "T — I -< 05 (N 1 S:: X X 0OO5— < CD 0505rt t- (MM -< CO CO CO int*0 (NCOIOCS(N— CO cooocococococooo T}" ic O 00 CO -H o -^ — ' CO CO OO CO ^x >.si <« UQ MU. 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X t: U.-1 ~i~i U-J -lu. ? .2 .2 .2 .2 .2 .2 ^ s I o i i c c c c c ^ 10 u o t t :-cpo8cOQCcp^si)f?P 5.S 2 fe o o — S-iJSSJ-JoooooojjESuJ-JuOuuOT; « CO o'o'5'o'c;= JUUUUUUOS oc oS CO cU U" '•-"■ '■■" "" " TfiJ" -V-T •T'V ^00 OQ UUtJtjUUUOUOOUUUCJUuSUtJCJOUOCJUUCJ ooascQ«y(JWuau,u.u.u.u.u,u.x> X,Z HHHHHHHHH II II o . o 2.2 5 I o a, Q S E a .11 E § = E e u a, u u E s"^ 5? a o .-- = t •*' i2 § E a- i; •a •§ ^ - = 3 != i: = & S) „ 5 § K C V. ;'^ ^ t; S Q *- E ci. ■5 - to^ c li .S 5 becaus u,?. Dip Per cri imembr 'i^ f-- e to ares us leucu torridus, hus long IS ?, 0 «'?"=' •9 SO c S 3 used Amr tor- rg lo 1 30 5 .J! < Biological Series, Vol. 6, No. 3. Mabch, 1965 65 Dipodomys microps tends to decrease as Eurotm lanatci decreases, and Larrea divaricata and Fmnseria dumosa increase (Fig. 37). Onychomys torridus appears to decrease as Larrea divaricata, Atriplcx confertifolia, and Ettrotia lanata decrease; and Grayia spinosa and Sitanion hansenii increase (Fig. 38). Perognathus formosm seems to decrease with a decrease in Coleogyne ramosissima and an in- crease in Ephedra nevadensis and Oryzopsis hymenoides (Fig. 39). Perognathus longimembris appears to de- crease with a decrease in Lycium andersunii, Atriplex cenfertifolia, Eurotia lanata, and Ory- zopsis hymenoides and an increase in Larrea divaricata (Fig. 40). It is apparent that the interactions of these small mammal species with the vegetation in the biotic community can only be alluded to in the absence of quantitative data on the vegetation. Also, perhaps more samples would be needed in fewer more carefully selected sites in which distributional interrelationships between major biotic communities could be established. Seasonal Distribution Seasonal distribution was discussed by All- red, Beck and Jorgensen (1963a). Their data were presented as "butterfly" graphs and repre- sented relative estimates of abundance based on trap nights. Both relative densities and the trap night index can lead to rather misleading con- clusions if factors such as response to traps and activity are not considered, and neither proce- dure is designed to consider these variables. Ab- solute numbers were computed in this study to reduce the possibilitv of erroneous conclusions. The results of our analyses are presented in Figures 41-48. These figures do not include all of the species collected, for some were not col- lected in sufficient quantity to allow estimates of their densities. Each species will be briefly Table 18. Correlation coefficients for contrasting species of small mammals among the distribution transects. Species^ Species Amm leu Dip mer Dip mic Ony tor for Ion Ammospermophilus leucurus .0247 .3993"' • .0985 .1135 .3311"" Dipodomys meTtiami -.0370 .1687 .1766 .0409 Dipodomys microps .2251 .1588 .2741 Onychomys torridus -.2795 .0674 Perognathus formosus .0041 "Refer to left-hand species column for the abbreviated species names, except Prg Ion •""Significant at the 5% level. Perognathus longimembris. Table 19. Number of transects in which the presence and absence of certain small mammal species are contrasted. Species Present Species Absent - Species Amm leu Dip mer Dip mic Ony tor Prg for Prg Ion Total Transects Ammospermophilus leucurus 20 (29) 26 (37) 37 (53) 33 (47) 8 (11) 70 Dipodomys merriami 30 (38) 36 (45) 43 (54) 40 (50) 14 (18) 80 Dipodomys microps 19 (30) 20 (32) 31 (49) 27 (43) 9 (14) 63 Onychomys torridus 16 (31) 13 (25) 18 (35) 24 (47) 10 (19) 51 Perognathus formosus 16 (31) 12 (23) 19 (37) 26 (50) 13 (25) 52 Perognathus longimembris 29 (32) 23 (26) 36 (40) 48 (53) 50 (56) 90 Average percentage 32 27 39 52 49 17 "Refer to left-hand species column for the abbreviated species names. Percentages of the transects are in par- entheses. BllIGllAM VOLNC UnIVEHSITY SciE.NCE BULLETIN 0:° ^ in -< 00 ^ op O) 00 '^ CO (O t^ o d d o> o d o o o — c^ d d d -H c-j o o ■* o 05 d "2 d -^ s s o c q N -* d d d ^• -H — IN C — -H d oJ d ■* o 00 ^ op ^^ 05 p 00 OJ c CO d d t~ c t~ 05 p OJ o rt -^' d -H d „ CO -H -H -H (N O o CO -c — . TJ. CO — I -< CO -H Oj CO -c (>3 CO -i ■^ p p in t-^ d CO d O CO -< -H I = E Ji < t^ t^ IN 00 p •^ r- w M- O CO 05 O p o CO o c in —■cm (35 CO 05 — . -H O 00 O Ol C5 05 Ol 00 00 c 00 CD CD C CD i CD CD CD C5 o 00 CD 05 C-J CD 05 00 § c:> g §8 — i in ai —■' ^' ° t rt --i '^' -^ CO o t-^ ^ CO CO —i t-: ui CO —1 lO r-l t~ ■* O p r- oi io 05 o O) t- ■^ o p t^ t^ p ^ o -H CO d CO ,-, '-I -^ o o o o o d o d d d o o o o c d d d d c o fM o c — : o cj d d ;^ 10 10»OICO OCDloiO •* Tf Tt ■<}■ o C CO 'T ■* ''■ o o ■* CO - d d <6 d o -H ^ o P d -^ -^ d '^ o o o o o d d d d d o c o o o d d d d d o o o o P d d d d d E 1 3 CD in _, CD 00 CD OI m CI CD _ CO 'S Ol t (M 00 c-i in p CI in CO CI in ^ t~^ CO O 00 O 00 ci d ci d CI -*' S .2 2 i5 ^ "2 = -^ -2 3_ 5 -= £ ^ ^ ■= o 3 C :^ CJ o C a 1) S-. t<; :^ kJ ^ kJ - .5 S .2 c -S "S ~ '4-s 5 d, o o~ c 2 s tg £ S a 'm =1 •2 c ~ .2 ^^ c a a. .2 ..2 _c o o C3 6 Cj 2 1 ti ■| '5 a 0-. s cC i; C^ c^ tJ5 cJ5 E t 2 -2 *-»-. a :; S 3 ^ a g ~- ojo = 2 •- 2~ ^ a S CJ a, -5 •- o ^ 2 S £ "^ ^■:§ ■§'-§' CO CO ^ E*' E^ o iS Z 60 ^ •*r CL( ■W i« ^ o g •4.^ 3^ S 3 O CJ "e o s> 1 1 a- "S 1 o 2 Cu 4^ a s 5 S'e 6D ■£ B § g-O . o £ ' g ■^ -^ to . >.a; Pi 68 Bhicham Young University Science Buu-etin esuopunqv SAjioie^ uopunqv »A!>oi«ij Biological Series, Vol. 6, No. 3. March, 1965 SOUOpunqV 9A|iD|diJ eouopunqv 8a|4D|9^ 70 Bricham Yol'nc University Science Bulletin esuopunqv 9Ar(oteti -6 &- • suopunqv aAiioiCii Biological Series, Vol. 6, No. 3, Mabch, 1965 71 itlft harsh winter months. Perhaps the small popu- lation build-up during the 1961 season was due to the winter mortaUtv during the preceding winter. Perognathus longimembris (Fig. 44) has a seasonal distribution similar to that of P. for- mosus, being active essentially from March through September. They were captured only spKjradicaUy during the winter. Striking differences in numbers frequently appeared between successive years. During 1961 the population which had been present the previous year in 5E had dropped considerably. No explanation is readily available for this type of yearly decline. Figure 41. Seasonal distribution of Peromyscus truei; 12E - undisturbed Pinyon-Juniper. Numbers in parentheses represent those captured with no re- captures. Males — linear bars; Females — stippled bars. summarized to facilitate a better evaluation of these data. Peromyscus truei (Fig. 41) was collected abundantly only from Pinyon-Juniper commun- ities and then primarily from the grid which had not been disturbed by nuclear weapons testing. This grid (12E) was discontinued October, 1961 because of inclement conditions and not resumed until April, 1962. The lack of sampling accounts for the sudden drop. Peromyscus maniculatus (Fig. 42) was col- lected in small numbers in all of the grids, but was abundant only in the Pinyon-Juniper. Both of the grids placed in Pinyon-Juniper were dis- continued in October, 1961 because of inclement conditions. The differences in densities between April, 1962 and April, 1961 are rather striking in each grid. The wide fluctuations are not easily explained, but could be due in part to extended home ranges of females during the supposed lactating period. PerogTUithus formosus ( Fig. 43 ) was not col- lected during the winter months because of its inactivity. It became active during the early spring and generally remained active through October. Occasionally, a few individuals were trapped during the winter, but no explanation for this activity is available. During the summer of 1961 they were rather abundant in JA (Lar- rea-Franseria ) , but essentially absent from 5E ( Larrea-Franseria ) . Also in 5E there appear to have been more individuals active during the m _r Figure 42. Seasonal distribution of Peromyscus man- iculatus; 12E - undisturbed Pinyon-Juniper, 12A - disturbed Pinyon-Juniper. Numbers in parentheses represent those captured with no recaptures. Males — linear bars; Females — stippled bars. 72 Bhioham Young Univehsity Science BuLLmN Dipoclomys orclii (Fig. 45) was collected abundantly from only one grid (IF), and it was in a Salsola community. The high density during tlie spring of 1961 gradually decreased until November, when very few animals were pre- sent. Subsecjuent trappings in this area indicated that they have never yet returned in substantial numbers. It is evident that this reaction is a response to the Salsola kali which invaded the area shortly after the last nuclear weapons test (Shields and Wells, 1960). As growing condi- tions become less suitable for Russian thistle, and since no other vegetation has replac-ed it, the area was once again almost void of vegeta- tion. As the food supply in the summer of 1961 dwindled, so did D. orclii until in the winter it I i Month! Trapped k Figure 43. Seasonal distribution of Perogtiathus form- osus; JA - mixed Larrea-Fran.scria, 5E - Lyciitm pal- lidum association of Larrea-Franseria. Numbers in parentheses represent those captured with no re- captures. Males — linear bars; Females — stippled bars. appeared that there was not sufficient food or cover to maintain them. Dipoclomys merriami (Fig. 46) fluctuated considerably throughout the year, but was gen- erally most abundant in the spring and summer months. The rather significant decrease in IF during the spring of 1961 resulted essentially from the death of adults and sub-adults pre- sumably unable to survive the winter months. This decline resulted in their elimination, which has persisted since and probably resulted from the lack of food when Salsola kali failed to re- turn. The highest populations were evidently during the spring months when the largest num- bers of young were present. Dipoclomys microps (Fig. 47) had seasonal distributions which were generally similar to those of D. merriami except that the largest pop- ulation generally was somewhat later in the spring and early summer. Also, the decline dur- ing the winter months was usually more abrupt, sometimes resulting in practically no captures. This probably does not stem from hibernation behavior, for on trapping days which were favor- able, large numbers were frequently trapped (e.g. lOD; January, 1961). It seems more likely to result from foraging behavior. Trapping results of Ammosjyermophihis leu- curtis (Fig. 48) were extremely sporadic. This probably resulted from their large activity ranges and the fact that the grids were generally too small to include their movement. Also, since the traps were serviced during the early morn- ing only and A. leucurus is active during the day, many were found dead in the traps. Data for this species must be carefully evaluated, because the two behavior characteristics de- scribed would influence the trapping results considerably. Some general comments concerning these data may also be made. It is easily seen that rather Ifirge fluctuations in small mammal densities are evident from one month to the next. Also, rather large differences appear bet^veen the den- sities of males and females. On the surface those differenc ' / r^^wv y. ^ ---^ i/ic: Vj^s*^ MUS. COViP. ZOOL BRIGHAM YOUNG UNIVERSITY ^'^''^''^ JUL 'J i^t^y SCIENCE BULLETIN HARVARD UNIVERSITY. SCORPIONS OF THE NEVADA TEST SITE by Willis J. Gertsch and Dorald M. Allred Biological Series — Volume VI, No. 4 March 1965 BRIGHAM YOUNG UNIVERSITY SCIENCE BULLETIN SCORPIONS OF THE NEVADA TEST SITE by Willis J. Gertsch and Dorald M. Allred Biological Series — Volume VI, No. 4 March 1965 FOREWORD This is another of a series of major publications on desert ecolog\' resulting from studies at the Nevada Test Site bv the Brigham Y'oung University' Department of Zoolog)' and Entomology in cooperation with the United States Atomic Energy Commission. Although some of the studies are the result of independent investigations by specialists who are not on our departmental staff, they are part of the major projec-t initiated cooperatively by B.Y.U. and the A. E.G. to determine the effect of nuclear detonations on the native animals of the Nevada Test Site. Doruld M. Allrcd and D Elden Beck Project Supervisors MUS. COMP. ZOOL LIBRARY JUL y laoiJ HARVAKU UNIVERSITY TABLE OF CONTENTS INTRODUCTION 1 THE SCORPION FAUNA 1 Key to the Species of Scorpions 2 Family Vejovidae 3 Genus Vejovis 3 V. confusus 4 V. wupatkiensis 8 V. hirsuticauda 8 V. boreus 9 V. becU 9 Genus Anuroctonus 11 A. phaeodactylus 11 Genus Hadrurus 12 H. arizonensis 12 H. spadix 14 Family Chactidae 14 Genus Superstitionia 14 S. donensis 14 Ecological Summary 15 REFERENCES 15 LIST OF FIGURES Figure Page Vejovis becki, new species. Carapace of female • 3 Vejovis becki, new species. Sting of female, lateral view 3 Vejovis confusus Stahnke. Carapace of female 3 Vejovis becki, new species. Right chelicera of female, ventral view 3 Vejovis becki, new species. Sternum, genitid operculum and combs of female 3 Vejovis becki, new species. Right cheUcera of female, dorsal view 3 Vejovis becki, new species. Sternum, genital operculum and combs of male 3 Vejovis boreus (Girard). Left chela of female, dorsal view 4 Vejovis confusus Stahnke. Left chela of female, dorsal view 4 Vejovis becki, new species. Left chela of female, dorsal view 4 Vejovis wupatkiensis Stahnke. Left chela of female, dorsal view 4 Vejovis confusus Stalinke. Sting of female, lateral view 4 Vejovis hirsuticauda Banks. Sting of female, lateral view 4 Hadrurus arizonensis Ewing. Right chelicera of female, ventral view 6 Hadrurus arizonensis Ewing. Right chelicera of female, dorsal view 6 Anuroctonus phaeodactylus (Wood). Sternum, genital operculum and combs of female 6 Anuroctonus phaeodactylus (Wood). Sting of male, lateral view 6 Anuroctonus phaeodactylus (Wood). Sternum, genital operculum and combs of male 6 Anuroctonus phaeodactylus (Wood). Sting of female, lateral view 6 Distribution and relative abundance of scorpions in the various plant communities 7 SCORPIONS OF THE NEVADA TEST SITE' By Willis J. Gertsch^ and Dorald M. Allred' INTRODUCTION The distinctive body form of the scorpions distinguishes them as well-known land arachnids familiar to most peoples in temperate and trop- ical regions. In front large chelate pedipalps with grasping fingers reach out to seize and hold insects and other small ground animals making up their prey. The greatly elongated p>ostabdomen, or tail, which is looped forward over the body to strike in front of the head or to the side, bears a sharp terminal sting used to inject venom into their victims. The venoms of some scorpions (in North America almost exclusively those of a few species of Centru- Toides) contain neuroto.xic elements that cause severe or lethal systemic reactions in warm- blooded animals. In man the venoms of these species are capable of causing grave symptoms or even death, especially in children. No species of Centrurokles is known from the Nevada Test Site although the genus has a wide range in Arizona, even into some nortliem counties. This absence of Centruroides is also conspicuous in the Mojave Desert and other desert and foothill country of southern California which would seem to offer ideal conditions for the genus. Scorpions live in many climatic zones but have reached their highest de\elopment in warm, arid regions. They are nocturnal in habit and during the day hide under rocks or ground detritus, in biurows, or Ue buried in sand. By this activity pattern they escape the heat of the day. However, desert scorpions are especially hardy tvpes known to be able to survive the extremely hot air and ground temf)eratures of this habitat even better than desert insects. Scorpions hve for several vears and grad- ually attain full size by periodic molting. Dur- ing this development they modifv' some of their featiues to the confusion of the systematist. The population of any species is a somewhat hetero- geneous assortment with many variables of color base and pattern, size, and proportions of seg- ments affecting robustness, as well as sex. Ma- ture males of the V'ejovidae are topically smaller than females with more slender p>ostabdomens and stouter pedipaipi. Verv voung specimens can most often be assigned to the prof>er sex on the basis of features of the genital operculum and orifice. Such immature scorpions are less easilv placed to species because of morphologi- cal changes during growth. On the otlier hand, it is possible to rec-ognize some species on the basis of characters, sometimes seemingly trivia! details of color pattern, readily traced from young to adult, .'\lmost nothing is known about the bionomics of any of our North American sc-orpions. The systematics of our southwestern scor- pion fauna has been largely neglected in spite of the accumulation of hu'ge collections in var- ious depositories. The opportunitv to studv the present material from the Nevada Test Site was made available b\' Dr. D Eiden Beck and his associates of Brigham Young Universit)', to whom we proffer our sincere thanks. The re- sponsibilit\^ of the senior author of this paper rests with the systematics, whereas that of the jimior author is concerned with the bionomics and ecology. THE SCORPION FAUNA This paper is based on the large, representa- tive scorpion collections made from 19.59 to 1964 at the Nevada Test Site by members of Brigham Young University's Department of Zo- ology and Entomology. The physical appear- ance and biotic communities of this large ex- panse of arid land in southern Nevada, com- prising more than a thousand square miles, were described by AUred et al. (1963a and 1963b). Nine species of scorpions live in the area, and 'BYU-AEC Report COO-1335-5. Field work completed under AEC Research Grant AT( 11-1)786. "Curator, Department of Entomology, The American Museum of Natural History-, New York. 'Associate Professor, Department of Zoology and Entomology, Brigham Voung University, Provo, Utah. 2 BnicHAM YoLNC University ScrESCE Blxletin all repres<'nt now records for Nevada since there em Nevada are the most northern for this small ha\e been to our knowledge no published rec- species. ords of sc-orpions from the state. Few areas of The remaining eight species belong to the similar size in our southwestern region can boast family Vejovidae, the most notable of which of so large a representation of species. From are some species of the genus VcjolLs. Vejovis this same area Muma (1963) reported 28 twi/uvH.v Stahnke is the most abundant scorpion six-cies of another group of arachnids, the Sol- "^ f''*^" T^'=*^ ^'''' ''"^ accounts for more than pugida, also strongly represented in arid reg- V''^ *'•''' T^'""^ 'P^^^J'^'^^ "\ t»'e entire c-ollection. . " <-> . I " Vcpvis hirsuticauaa Banks is an uncommon ■ r , ^1 1 1 species until now known onlv from San Bemar- The sc-orpion famil>' Chactidae is represented j\„^ Count^^ CaUfomia. adjacent .'Arizona, and by SuperstitUmu, chncisii Stahnke, which oc- northern Ba'ja CaUfomia. Vejovis- boreus Cirard curs in the foothill country from eastem Ari- j^ a boreal spec-ies with ven- uide distribuHon, zona to southern California and southward into which lives at the Test Site with its near rela- Baja California. Tlie present rec-ords from south- ti\e, Vejovis becki, new sf>ecies. KEY TO THE SPECIES OF SCORPIONS 1. Onlv tv\o side eyes present (Family Chactidae) Superstitionia doiiensis Stahnke Three principal side eyes present (Family Vejovidae) 2 2. Lower margin of movable finger of chelicera with single conspicuous dark tooth (Fig. 14); genus Hadrurus 3 Louer miirgin lacking single large tooth, variable, with keel smooth, crenate, lobed or pluridentate 4 3. Carapace all dark brown or black to front margin Hadrurus spadix Stahnke Carapace pale in interocidar area Hadrurus arizonetisis Ewing 4. Middle lamellae of pectines consisting of about five irregular pieces (Fig. 16); telson of male usually with swollen sting (Fig. 17); pedipalps heavy with black fingers Anuroctonus phaeodactylus (Wood) Middle lamellae consisting of si.x or more regular pieces (Fig. 5) 5 5. Hand cf pedipalp essentially smooth; lower margin of movable finger usually smooth 6 Hand of pedipalp with prominent, granulose keels; lower margin of mo\able finger us- ually crenulate or dentate 8 6. Vesicle of telson ( Fig. 13) with thick bnish of vcPv' long, soft hairs Vcjaois hirsutkauda Banks Vesicle of telson with only a few scattered hairs or bristles 7 7. Hand of pedipalp (Fig. 9) with fi.ved finger somewhat longer than palm Vejovis confusus Stahnke Hand of pedipalp (Fig. 11) with fi.\ed finger very much longer than palm Vejovis u'upatkiciisis Stahnke 8. Haiul of pedipalp (Fig. S) robust, with palm as broad as length of fixed finger; fingers relatively short, with inner margins sinuate or angled; preabdomen with d;u-k pattern ... Vejovis boreus (Girard) Hand of pedip.ilp (Fig. 10) more sliMKler, with palm about half as broad ;is fi.xed finger; fingers more slender, with inner margins not much angled; preabdomen pale Vejovis becki. new species Biological Series, Vol. 6. No. 4, March, 1965 Fig.s. 1, 2. Vejovis hecki, new species. 1. Carapace of female. 2. Sting of fem;de, lateral view. Fig. 3. Vejovis confu.sus Stahnke, carapace of female. Figs. 4-7. Vejovii becki, new species. 4. Right chelicera of female, ventral view. 5. Sternum, genital operculum and combs of female. 6. Right chehcera of female, dorsal view. 7. Sternum, genital operculum and combs of male. Family Vejovtdae Genus Vejovis Koch The genus Vejovis comprises the largest and most diverse generic group of the largely Amer- ican family Vejovidae. Species are numerous in the United States and Mexico but none occurs in tropical America. In the past the genus has been restricted to mostly small species with numerous middle lamellae and numerous teeth in the pectines and without so-called teeth on the lower margin of the movable finger of the chelicera. This last feature is subject to consid- erable variation, is inexplicit as now used, and has occasioned the formation of genera here considered superfluous. In some, mostly small species of the genus as here used, the lower cheliceral margin of the movable finger is es- sentially smooth. In other mostly larger species it is irregularly dissected into trivial, unequal lobes or teeth, and finally in large or robust species it is frequently dissected into irregular lobes or series of dark teeth. All these extremes can be found in species groups otherwise close- Briciiam Young University Science Bulletin Fig. 8. Vejovis boreus (Girard), left chela of female dorsal view. Fig. 9. Vejovis confusus Stahnke, left chela of female, dorsal view. Fig. 10. Vejovis becki, new .species, left chela of female, dorsal view. Fig. 11. Vejovis wupatkiensis Stahnke, left chela of female, dorsal view. Fig. 12. Vejovis confusus Stahnke, sting of female, lateral view. Fig. 13. Vejovis hirsuticauda Banks, sting of female, lateral view. ly bound together by many other features. It seems clear that the genus Vroctonus, seeming- ly distinctively based on a smaller number of middle lamellae and teeth on the chehceral carina, and Paruroctonus, based on a larger number of such lamellae and chehceral teeth, are merely opposite ends of a series with many intergrading elements. To maintain tlit^e genera would demand further subdivision of Vejovvi into other e(|uallv valid taxa and result in un- desirable fragmentation of a group at present not e.xcessive in size. In this paper Paruroctonus is regarded merely as a subgenus, as one of tlie species groups of Vejovis, and easily contained witliin the boreus group. A corollary is the necessity to incorporate the whole subfamily Uroctoninae into the Vejovinae. Vejovis confusus Stahnke Figures 3. 9, 12, 20; Table 1 Vejovis confusus Stahnke, 1940, Iowa State College Jour. Sci., vol. 15, p. 101. Vejovis flavus Stahnke, 1956, Scorpions, Sec- ond Edition. Arizona State College, Tempe, .\rizona, p. 27, fig. 10. Type data. Svnt^■pes from Coolidge, Mesa, Superior, Tucson, W'ichenburg, and Casa Grande National Monument in .Arizona. In Arizona State University collection (H. L. Stahnke). Diagnosis. This very common species, wliich has been confused with Vejovis flavus Banks of New Mexici), is of small to median size and sometimes attains 55 mm in length. The whole bmlv varies from vellow to orange-brown and Biological Series, Vol. 6, No. 4, March, 1965 Table 1. Measurements (in millimeters) of species of Vejovis. toupath iensls hirsitticauda confustts Female Male Female Male Female Male Total length 34.0 25.9 36.5 35.1 47.3 39.1 Carapace Length 4.2 3.4 4.5 4.7 5.8 4.9 Width at side eyes 2.3 1.8 2.3 2.2 3.5 2.7 Width at caudal edge 4.1 3.0 3.8 3.8 5.5 3.8 Preabdomen Length 10.3 6.5 12.0 9.0 14.0 10.0 Width 4.3 3.0 4.2 3.8 5.3 4.2 Postabdomen, length 19.5 16.0 20.0 21.4 27.5 24.2 Segment I Length 2.2 1.7 2.2 2.5 3.0 2.7 Width 2.3 1.9 2.0 2.2 3.4 2.5 Segment II Length 2.4 2.0 2.6 3.0 3.2 3.0 Width 2.2 2.0 1.8 2.0 3.3 2.5 Segment III Length 2.7 2.1 2.9 3.1 3.5 3.0 Width 2.1 2.0 1.7 1.8 3.3 2.5 Segment IV Length 3.0 2.7 3.5 3.8 4.8 4.0 Width 2.0 1.8 1.5 1.7 3.5 2.6 Segment V Length 4.7 3.8 4.5 5.0 6.3 5.5 \\'idth 1.8 1.8 1.3 1.5 3.5 2.6 Telson, length 4.5 3.7 4.3 4.0 6.7 6.0 Vesicle Length 2.7 2.2 2.5 3.0 4.5 3.7 Width 1.4 1.3 0.9 1.0 3.2 2.3 Depth 1.2 1.0 0.9 1.0 2.3 1.9 Spine, length 1.5 1.3 1.5 1.5 2.0 1.7 Pedipalp 16.1 12.5 13.6 14.0 18.4 15.7 Femur Length 4.2 3.2 3.3 3.5 4.7 4.1 Width 1.0 0.8 1.3 1.3 1.5 1.1 Tibia Length 4.5 3.5 3.5 3.5 5.2 4.8 Width 1.3 1.0 1.5 1.5 1.9 1.4 Hand Length 7.4 5.8 6.8 7.0 8.5 6.8 Width 1.5 1.3 2.0 2.8 2.2 1.5 Depth 1.3 1.1 2.3 2.7 2.0 1.4 Palm length 3.1 2.5 4.0 4.5 4.0 3.2 Moveable finger, length 5.0 3.7 3.7 3.5 5.3 4.6 Combs, number of teeth 15-16 17 15-16 16-18 13-17 17-19 BmcHAM Yoi'Nc I'sivERsiTY Science Bulletin Figs. 14, 15. Iladrurus arizonensis Ewing. 14. Right chelicera of female, ventral view. 15. Right chelicera of female, dorsal view. Figs. 16-19. Amiroctonus phaeoJactijlus (Wood). 16. Sternum, genital operculum and combs of female. 17. Sting of male, lateral \iew. 18. Sternum, genital opereuUim and combs of male. 19. Sting of female, lateral view. usually lacks darker contrasting markings. This is a variable scorpion in morphological features. Smaller sj^ecimens are usually slender, but larg- er and presumably older specimens ha\e thick abdomens. The telson is rather thick but bears a short sting. In females with thick cauda the telson is often heavy and ccmspiciiously granu- lated. The fingers of the pedipalpi are long and slender as are the palms of the hands which are smooth or very weakly granulated. Coloration. Base color yellowish to dusky brown in preser\'ed specimens; appendages and underside paler. Carapace without contrasting markings except for black eyes and tubercles. Preabdomen and postabdomen t^'l)ically im- marked with granidated keels and black sting providing some contrast. Males somewhat paler, often with narrow black seam outlining tergites. Structure. Similar in both sexes but male more slender with proportionately longer post- abdomen. Carapace: Slightly longer than broad in fe- male, considerabh' longer in male (Fig. 3). An- terior margin essentialK' straight, set with six suberect bristles. Surface granulose, with rows and clusters of large granules (ner most areas. Median groo\'e distinct to near caudal edge and siiallow trench passing for\vard to margin. Med- ian e\'es small, set on low tubercle; width of median diad about one-fiftli the widtii of cara- Biological Series, Vol. 6, No. 4, March, 1965 ANUROCTONUS PHAEODACTYLUS HADRURUS ARIZONENSIS HADRURUS SPADIX SUPERSTITIONIA OONENSIS VEJOVIS BECKI VEJOVIS BOREUS VEJOVIS HIRSUTICAUDA VEJOVIS CONFUSUS VEJOVIS WUPATKIENSIS MIXED LY LA -FR GR-LY AR CO SA AT-KO PI-JU if 71= 100 SPECIMEN S_ = L£SS THAN 25 SPECIMENS Fig. 20. Distribution and relative abundance of scorpion.s in the various plant communities. pace at this point. Lateral eyes of each side three in number, of which posterior one is smal- ler and set above others. Preabdomen: Tergites granulosa, with sev- eral transverse rows of heavy granules in pos- terior half of each segment; tergite VII with heavy, granulose keels. Postabdomen: Dorsal and superior lateral keels prominent, set with heavy granular teeth, of which last one on each segment only slight- ly enlarged. Inferior lateral keels distinct and granular but those on basal segments less prom- inent. Inferior median keels weak and smooth on first, stronger and smooth on second, par- tially granulate on third, and strong and gran- ulose on apical segments. Fifth segment slight- ly longer than carapace in both sexes, with num- erous coarse granules between ventral keels. Telson: Sting short, curved, about half as long as vesicle (Fig. 12). Subaculear nodule pre- sent. Vesicle not fully as wide as segment V of postabdomen, set with rows of conspicuous, rounded granules. Pectines: Those of female small; median piece deeply grooved in front half, two-thirds as long as wide; middle lamellae consisting of about 10 rounded pieces; pectinal teeth short, broad at apices, numbering 13 or 14. Those of male much larger and broader as usual; median piece as in female; middle lamellae about 12 rounded, less distinct pieces; pectinal teeth larger, curved, numbering 17 to 19. Genital operculum: Similar to that of Vejovis becki ( see figs. 5, 7 ) . Chelicerae: Tooth structure typical for gen- us; lower margin of movable finger with keel essentially smooth, weakly crenate under higher power. Pedipalps: Femur of female about three times as long as broad, with all carinae promi- nent and granular. Tibia not fully three times as long as broad, thickened below, with carinae distinct and granulate. Hand essentially smooth, without distinctive keels (Fig. 9). Inner keel of both fi.xed and movable fingers with unequal series of close-set brown teeth, broken into six groups by enlarged teeth flanked by six large supernumerary teeth. Hand of male thinner than that of female. Distribution and abundance. Known from southern Nevada and the warmer parts of Ari- zona and adjacent California. This was the most abundant and widely distributed species at the test site. It was taken in areas 1, 4, 5, 6, 10, 12, A, B, C, E, J, M, and T. It was found in every plant community, but was predominant in Grayia-Lycium, Larrea-Franseria, and Mixed. Brkmiam Yoi'Nf. Univkrsity SciENfE Bulletin It was least abundant in Atriplcx-Kocliia and Pinvon-JuniptT. A total of 858 specimens was colli'tted. Sex ratio and seasonal occurrence. Many of our eariv identifications did not include sex dif- ferentiation. However, from a random sample of about 200 specimens, there were about half again as many males as females. Adult males were active from May through September, pre- dominantly in Jul\- and .\ugiist. Females were active from .\prii through September, predom- inantly in June. Immature scoq)ions were taken from Nlay through September, predominantly in June. Other scorpions not detennined to sex were taken in small numbers as early as March and as late as November. Vejovis wupatkiensis Stahnke Figures 11, 20; Table 1 Vejovis umpatkiensis Stahnke, 1940, Iowa State College Jour. Sci., vol. 15, p. 101. Type data. Male and female syntypes from the W'upatki National Monument near Flagstaff, Arizona. In the collection of .\rizona State Uni- versity (H. L. Stahnke collection). Diagnosis. This is a small, slender scor|:)i()n which rarely exceeds 35 mm in length. The en- tire body is uniform yellow to orange-brown without contrasting darker markings. The smooth carapace, which has the front edge es- sentially straight, is finely granular with few- conspicuous larger granules. The eyes are small and the median diad covers little more tlian one-fifth the width of the carapace at that point. The conventionally toothed chelicerae have the lower margin of the movable finger essentially smooth. The hands of the pedipalp bear incon- spicuous keels which are set irregidarly with granules (Fig. 11). Tlie fingers are very long and the movable finger is nearly twice tlie length of the palm. All keels on the post- abdomen are distinct and granular except the inferior median keels on segments I and II which are very weak. The sting of the telson is t\vo-thirds the length of the vesicle and often bears a subaculear tubercle or distinct tooth beneath the base. Distribution aiid abundance. Known from northern .\ri/.()na westward to Nevada and adja- cent California. This species is seventh in abundance at the test site. Geographically it was found in areas 1, 4, 5, A, C, J and M. Ecologicallv it was found predominantly in the Mixed community, and infreiiuently in Grayia- Lycium, Larrea-Franseria, Lvcium, and Salsola. Twenty-eight specimens were collected. Sex ratio and seasonal occurrence. Males and females were taken in about equal numbers, with females slightly predominant. Adult males were active in July, August, October, and No- vember, and females the same months plus March, June, and September. Immature scor- pions were taken in June, July, and August. Vejou.s iiirsuticauda Banks Figures 13, 20; T;il)le 1 Vejovis hirsuticauda Banks, 1910, Pomona College Jour. Ent., vol. 2, p. 189, fig. 81J. Ewing, 1928, Proc. U. S. Nad. Mus., vol. 7.3, art. 9, p. 10 (Vacjovis). Type data: Female type from San Bernar- dino County, California. In the Museum of Comparative Zcx)log\', Harvard University. Diagnosis. The small, uniform yellow to orange-brown scorpion shows little sexual di- morphism and rarely exceeds 40 mm in length. The carapace, which has a small but distinct emargination in front, and preabdomen are studded with distinct coarse granules over much of the surface. All the carinae on the post- abdomen are well developed and evenly set with small, pointed denticles. The thin post- abdomen diminishes gradually from base to tip and ends with an elongated telson liberally clothed with a thin brush of fine hairs mostly on the \entral surface (Fig. 13). This distincti\e feature makes the common name "hairy-tailed scorpion" verv' appropriate. The hands of the pedipalp are considerably incrassated and the distinct keels are set with coarse granules. The fingers are of moderate length with the mov- able one about equal to the length of the palm. The lower margin of the movable finger of the chelicera is essentially smooth and bears only small points and irregularities under high power. The combs are of a\erage size for the group, and the teeth vary from 15 to 16 in females and 16 to 18 in males. Distribution and abundance. Knoun from southern .Nevada and adjacent California, south- ward into Baja California. This species is next to the least abimdant at the test site. It is geo- graphically limited to areas 5, A, C, and J. Ecologicailv it was found predominantly in the Mixed community and infrequently in Larrea- Franseria and L\ciiuii. (^nly 18 specimens were taken. Sex ratio and seasonal occurrence. Males and fiMiales were taken in about eijual numbers. BioLCXJiCAL Series, Vol. 6, No. 4, March, 1965 Adult males were active in June, July, Septem- ber, and October, and females during the same months plus May. Immatures were found in June and October. Vejovis boretis (Girard) Figures 8, 20; Table 2 Scorpio (Telegonus) boreus Girard, 1854, in Marcy, E.xploration of the Red Ri\er of Louis- iana in the year 1852, p. 257. Vejovis silvestrii BorreUi, 1908, Bol. Lab. Zool. Gen. Agraria, Portici, vol. 3, pp. 225-227. Vejovis boreiis Ewing, 1928, Proc. U. S. Natl. Mus., vol. 73, art. 9, p. 12. Gertsch, 1958, Amer. Mus. Novitates, no. 1903, p. 6. Type data. The Valle)' of the Great Salt Lake. Specimen collected by Captain Howard Stansbury. Diagnosis. This is a medium-sized scorpion of conventional pale yellow coloration with a V-shaped black marking centered on the med- ian eyes, and dusky tiansverse bands on the segments of the preabdomen. Specimens from the Nevada Test Site are lightly marked with black as compared with the bold, black pattern of examples from the California mountains. The median eyes are average in size, set on a low tubercle, and the width of the diad is at most one-fourth the width of the median eyes at that point. The inferior median keels of the Cauda are essentially obsolete on segments I to in, but their presence is indicated by a pair of diffuse, brown bands. The thick hands of the pedipalpi are provided with well-marked ridges bearing numerous granules (Fig. 8). The chelicerae are rather small and have the keel on the lower margin of the movable finger ir- regularly crenate as in becki. The pectinal tooth count is variable, in females being about 19 and in males 25 to 30. For comparative mea- surements, see Table 2. Distribution and abundance. This wide- spread species, called "northern scorpion" bv Ewing in 1928, ranges widely from the southern Canadian Provinces (Saskatchewan to British Columbia) southward into Mexico. This was the fifth most abundant scorpion at the test site. It was found in areas 5, 10, 12, E and J. It was collected in all the plant communities except Atriplex-Kochia, Coleogyne, and Salsola, although it occurred in abundance only in the Pinyon-Juniper. Sixty specimens were collected. Sex ratio and seasonal occurrence. Males and females were taken in a ratio of 6:1. Adult males were active from June through Septem- ber, predominantly in the latter three months. Females were active also from June through September. Immatures were taken only in July. Vejovis becki, new species Figures 1, 2, 4-7, 10, 20; Table 2 Type data. Male holotype from the Nevada Test Site, approximately 34 miles due north of Mercur)', Nye County, Nevada, taken 21 July 1961. (Brigham Young Universitv Ref. No. 275, Collection Code lODAllC). Captvired in a sunken ain trap in a Coleogyne ramosissima plant community (refer to Allred, Beck, and Jorgcnsen, 1963b); deposited in American Mus- eum of Natural History. Diagnosis. This species belongs to the boreus group of Vejovis, which comprehends in addition to the txpical species (boi-eiis Girard and acjuilonalis Stahnke) the three North .Amer- ican species assigned to the genus Paruroctonus {gracilior Hoffman, mesaensis Stahnke, and vachoni Stahnke). Vejovis becki agrees with the first two species of this latter group in having the dark median eyes greatly enlarged so that the diad is about one-third the width of the carapace at that point. It is a much smal- ler and more slender species than vachoni and far less slender than mesaensis, from which it is readily separated by the lesser number of teeth in the pectines and the lack of distinct dark granules or teeth at the base of the fixed finger of the chelicera. In general appearance it resembles gracilior, but the chela of the ped- ipalp is far thinner with much longer fingers. Vejovis becki is considerably paler and never bears the dark markings on the preabdomen present in boreus. Measurements are given in Table 2. Coloration. Base color yellow to orange- brown in preserved specimens of both sexes, but legs and pectines pale yellow and flexible cuticula white. Carapace with dark pattern as follows: Eyes and eye tubercles black; dark central dusky patch enclosing median eyes and from it inconspicuous dusky shadings radiating forward and to sides. Preabdomen and post- abdomen unmarked; tip of sting dark red. Structure. Similar in both sexes but males as usual in this group smaller and somewhat more slender as shown in comparative measure- ments. Carapace: Clearly longer than broad in both sexes (Fig. 1). Anterior margin essentially straight, set with six suberect bristles. Much of surface finely granulose, with rows of coarser 10 Bricham Young University Science Bulletin Table 2. Measurements ( in millimeters ) of species of Vejovis and Anuroctonus. V. boreus V. becki A. phaeodactyliis Female Male Female Male Female Male Total length 44.5 46.1 45.9 37.3 58.7 62.2 Carapace Length Width at side eyes Width at caudal edge Preabdomen Length Width Postabdomen, length Segment I Length Width Segment II Length Width Segment III Length Width Segment IV Length Width Segment V Length Width Telson, length Vesicle Length Width Depth Spine, lengtli Pedipalp Femur Length Depth Tibia Lengtli Depth Hand Length Width Depth Palm length Movable finger, lengdi Combs, number of teeth 19 25-30 5.5 5.5 3.3 3.3 5.2 5.2 14.5 12.0 6.0 5.5 2A.5 28.6 2.5 3.0 2.8 3.0 2.7 3.4 2.5 2.9 3.0 3.8 2.5 2.8 4.0 4.5 2.5 2.6 6.0 7.2 2.5 2.7 6.3 6.7 4.5 4.5 2.6 2.6 2.3 2.0 2.3 2.2 15.4 18.3 4.3 4.8 1.4 1.5 4.8 4.8 1.7 1.9 6.3 8.7 3.3 3.0 2.7 4.0 4.5 5.0 5.3 5.6 5.7 4.3 10.0 9.5 3.5 2.7 6.2 5.5 5.0 3.8 9.0 8.3 13.7 9.0 17.0 20.0 5.5 4.2 8.7 8.5 26.5 24.0 .31.7 32.7 2.7 2.7 3.0 3.0 2.7 2.2 4.0 3.7 3.0 3.0 3.5 3.5 2.4 2.1 3.7 3.5 3.3 3.3 4.5 4.3 2.3 2.0 3.6 3.3 4.3 4.0 5.5 5.5 2.1 1.8 3.5 3.3 6.5 5.7 7.5 7.7 2.3 1.7 3.5 3.0 6.7 5.3 7.7 8.7 4.3 3.5 5.0 6.4 2.5 1.7 2.7 3.7 2.2 1.4 2.7 4.3 2.3 1.8 2.5 2.9 17.2 14.8 29.5 29.0 4.5 4.0 6.0 6.0 1.3 1.0 2.7 3.0 4.5 4.0 7.0 7.5 1.7 1.2 3.5 4.3 8.2 6.8 16.5 15.5 L7 1.7 6.0 5.3 1.9 1.8 5.0 6.3 4.0 3.5 9.0 10.0 5.2 4.0 8.8 8.5 17-21 24-29 5-7 8-10 Biological Series, Vol. 6, No. 4, March, 1965 granules forming inconspicuous lines and patch- es. Median groove distinct from median eyes to posterior margin, with flanking elevations set with coarse granules. Median eves large, on conspicuous oval tubercle; width of median diad about one-third the width of carapace at this point. Lateral eyes of each side three in num- ber, of which posterior one is smallest. Preabdomen: Traces of weaklv granulated median keel on tergites I to VII still persistent. Tergites finely granulose throughout (essentially smooth under low power), with transverse rows of inconspicuous granules on posterior edges of tergites and more conspicuous scattered series on posterior tergites. Postabdomen: Dorsal and superior lateral keels prominent, surmounted with rows of ser- rate to crenate teeth of regular size. Inferior median keels essentially obsolete on segments I to III, represented on segment IV by slight, smooth keels, and on segment V with single granulate median keel. Inferior lateral keels on segments I to III largely smooth, on seg- ment IV smooth with series of weak granules in distal half, on segment V with series of serrate teeth becoming larger apically. Segment V slightly longer than carapace in female, consid- erably longer in male. Tclson: Sting moderately curved, shorter than vesicle (Fig. 2). Subaculear nodule not present. Vesicle about as wide as segment V of postabodmen. Pectines: Those of female small and of med- ium width as shown in Fig. 5; median piece broader than long; middle lamellae consisting of about 20 small oval pieces; fulcra small, sub- triangular; pectinal teeth of medium length and stoutness, numbering 17 to 21 in three females; those of male much larger and broader (Fig. 7); median piece about as long as broad; mid- dle lamellae about 30 small round to oval pieces; pectinal teeth long, curved, numbering 24 to 29 in 20 males examined. Cenital operculum: In the female with a longitudinal fissure but free only in posterior fourth (Fig. 5); in the male free for most of length ( Fig. 7 ) . Chelicerae; Tooth structure typical, that of female shown in figures 4 and 6; upper margins of both fingers with strong teeth; lower margin of fi.ved finger essentially obsolete, with weak keel and faint granulations; lower margin of movable finger with distinct thin keel of which edge is irregularly crenate to form weak pale rounded denticles. Pedipalps: Femur of female about three times as long as broad, with all carinae distinct and granulated. Tibia not fully three times as long as broad, narrowed at base, inflated at center, with all carinae granulated. Chela rath- er thin with long fingers (Fig. 10). Hand with low carinae set with small granulations. Inner keel of fixed finger with thick series of close- set brown teeth broken into six groups by en- larged teeth, adjacent to which are six large supemumerarv' teeth. Inner keel of movable fin- ger like fi,xed finger but bearing additional supemumerarv tooth near distal end. Male like female but an additional supernumerary tooth often present. Distribution and abundance. Known from southern Nevada and adjacent California. This species was the third most abundant taken at the test site. It was widely distributed geo- graphically, found in areas 1, 4, 5, 6, 10, C, E, and J. Ecologically it was also widely distrib- uted, found in all the plant communities except Artemisia and Pin\on-Juniper. It was predom- inant and about ecjual in numbers in Atriplex- Kochia, Grayia-Lycium, Larrea-Franseria, and Mixed communities. A total of 114 specimens was collected. Sex ratio and seasonal occurrence. Males and females were taken in a ratio of 2:1. Adult males were active from May through Septem- ber, predominantly June. Females were active from March through November. Immature specimens were taken from April through Sep- tember, predominantly in July and August. Genus Anuroctonn^ Pocock This exclusively American genus is repre- sented by the single distinctive species diag- nosed below. Anurocfonus differs from the mordax group of Vejovis only in the following features: The fourth segment of the postab- domen completely lacks inferior ventral keels whereas those on the preceding segments are distinct and granular. The sting of the telson in most males is inflated at the base. The med- ian lamellae of the pectines consist of a few irregular pieces. Amiroctonus phaeoclactijlus (Wood) Figure.s 16-20; Table 2 Centrurus phaiadactijlus Wood, 1863, Proc. Acad. Nat. Sci. Philadelphia, p. Ill; 1863, Jour. Acad. Nat. Sci. Philadelphia, ser. 2, vol. 5, p. 372. Amiroctonus phacodactijltis Pocock, 1902, Biologia Centrali-Americana, Arachnida, Scor- piones, Pedipalpi and Solfugae, p. 14, pi. 3, figs. Bmr.nAM VouNc Universitv Science Bulletin 4-4f, pi. 4, figs. 1-lc. liwing, 1928. Phk-. U. S. Natl. Mils., vol. 73, art. 9. p. 14. Hoffmann, 1931, An. last. Biol, .\le.\ico, pp. 40.3-405. Certscii, 1958, AmtT. Mus. Novitates, no. 1903, p. 14. Type data. Male type from L'tali Territory. Presumed to be in the U. S. National Museum (Smithsonian Museum). Diagnosis. This stout sc-orjiion is of medium to large size and often attiiins a length of about 90 mm from front of carapace to tip of sting. In size it is overshadowed by species of Haclru- rus. Its base color is dull yellow to dark brown, and the heavy pedipalps bear short black fin- gers. The front margin of the rough, granular carapace is provided with a shallow \'-shaped emargination. The median eyes are rather small with the diad ecjualing about one-si.\th the width at that point. The vesicle of the telson is hirge, shining veilow, and in typical males the black sting is inflated at the base (Fig. 17). In some smaller males the sting resembles that of the female in being drawn out e\enly as a curved spine (Fig. 19). The ventral keels on the post- abdomen arc distinct and cvarsely granular on all segments but IV where they are obsolete. The heavy hands are smooth above with smooth keels, but the sides and ventral surfaces bear coarse granules. The chelicerae are liirge, toothed as in Vejovis, and the lower margin of the movable finger bears one to three small, pale teeth near the base, llie genital operculum is \er\- large in the female, is deeply grooved longitudinalh', but remains tied for most of the length (Fig. 16). In the male the genital oper- culum is nearly as large as that of the female, is deeplv grooved to form free valves, and pre- sents distinct papillae at the posterior edge ( Fig. 18). The pectines are rather small, separated by a large median piece, and the teeth are few in number — 5 to 6 in females, 8 to 10 in males. Distribution and abundance. Known from Utah, southern Nevada, and southern California to Baja California. This scorpion is not c-onsid- ered to be abundant at the test site, ranking si.xth in occurrence. IIowe\er, it is widely dis- tributed geographically, found in areas 1, 4, 5, 6, 12, C, J. and T. Ecologically, it was most abundant in the Crayia-Lycium communit\', next common in .\rtemisia and ,\triplex-Kochia, and was taken only rarely in Coleogync, Lycium, and Mixed communities. Forty-eight specimens were taken. Sex ratio and seasonal occurrence. Males and females were taken in a ratio ol 13: 1. .\tlult males were active from July tiirough September. most predominantK' in .■\ugust. .\dult females were taken in small numbers only in Januar\', March, and June. Immature scorpions were tak- en in about e(|ual numbers in March, June, and October. Genus llatlruru.s Thorell The presence of a single, large, sharp tooth on the lower margin of the movable finger of the chelicera (jiiicklv identifies this North Amer- ican genus (Fig. 14). The genital operculum is grooved longitudinallv with the two valves free in both sexes, but genital papillae are lacking in males as well as females. The broader than long middle piece of the comb bears a deep groove in front at the mid- dle and is similar in both sexes. The combs are large, supplied with numerous teeth as in species of the Vejovis boreus group, and show the sexiial dimorphism of that genus, those of the male being larger with longer, more num- erous teeth. The presence of many hirge bristles on the appendages and distal segments of the postabdomen, far more numerous than in our other scorpions, has occasioned the popular name "giant hairy scorpions" for these, our largest and in some ways most distinctive scor- pions. The systematic status of the three popula- tions of Hadrurus in the United States {hirstitus Wood, arizonctisis Ewing, and spadix Stahnke) at present given specific status presents a dif- ficult and interesting problem. There seems to be little or no morphological difference between them and they largely replace each other geo- graphicallv. The color features separating hir- siitus, which is a large form with pale pre- abdomen largely confined to southern California and adjacent .Mexico, from the commoner, wide- spread darker aiizonensis are not so precise as one would wish. It seems likely that arizonensis is merelv a subspecies of hirmitus. The status of spadix remains obscure but it seems prob- able that it deserves specific status. The all- dark color of the carapace and tnmk is an in- variable feature of adults and young specimens of many sizes. There are no intergrades be- tween spadix and arizoneiisis and they oc-cur together at the Ne\ ada Test Site. Hadrurus arizoiiensis Ewing Kii;uri-s 14. 1.5. 20; Table 3 Hadrurus hirsutus arizonensis Ewing, 1928, I'roc. U. S. Natl. Mus., vol. 73, p. 8. Hadrurus arizonensis Stahnke, 1945, .\mer. .Mus. Novitates, no. 1298, p. 6; 1956, Scorpions. Biological Series, Vol. 6, No. 4, March, 1965 13 Table 3. Measurements ( in milhmeters ) of species of Hadrurus and Superstitionia. H. arizonensis H. 5- padix S. donensis Female Male Female Male Female Male Total length 102.6 108.5 96.2 104.0 23.8 22.6 Carapace Length Width at side eyes 13.5 10.7 13.0 9.0 11.0 7.0 13.0 8.3 2.8 1.7 2.8 1.7 Width at caudal edge 13.5 13.0 11.0 13.0 2.8 2.8 Preabdomen Length 26.0 26.5 30.0 27.5 8.5 5.7 Width 14.0 14.5 13.0 13.0 3.0 3.2 Postabdomen, length 63.1 68.0 55.2 63.5 12.5 14.1 Segment I Length 7.5 8.5 6.7 8.0 1.2 1.2 Width 7.0 6.7 6.1 7.0 1.8 2.1 Segment II Length Width 8.7 6.5 9.5 6.3 7.5 6.8 9.0 6.2 1.3 1.7 1.3 2.0 Segment III Length Widtli 9.4 6.3 10.5 6.3 8.0 6.8 9.5 6.0 1.5 1.7 1.6 2.0 Segment IV Length Width 10.5 6.1 11.5 6.3 9.5 5.6 10.5 6.2 2.2 1.7 2.6 2.0 Segment V Length Width 13.0 5.3 14.0 6.0 11.0 5.5 13.0 6.0 3.3 1.2 3.7 2.0 Telson, length 14.0 15.0 12.5 13.5 3.0 3.7 Vesicle Length Width 10.0 6.2 10.0 5.8 7.5 5.3 9.0 6.5 2.3 1.6 2.6 1.7 Depth Spine, length 5.8 4.0 5.5 4.5 4.8 4.5 5.7 4.5 1.2 0.8 1.3 1.0 Pedipalp, length 41.0 43.0 35.5 42.5 8.0 8.0 Femur Length Width 10.0 3.5 11.0 3.3 8.8 2.8 10.5 3.2 2.0 0.7 2.0 0.7 Tibia Length Width 12.0 4.6 12.0 4.3 10.0 3.8 12.0 4.0 2.3 1.0 2.3 1.1 Hand Length Width 19.0 6.5 20.0 6.3 16.7 5.0 20.0 5.7 3.7 1.2 3.7 1.8 Depth Palm lengtli 5.0 10.0 4.5 9.5 4.0 7.5 4.3 9.5 1.2 2.3 1.7 2.3 Movable finger, length 13.0 13.3 11.7 13.6 2.0 2.0 Combs, number of teeth 27-33 33-39 27-33 34-39 ±6 ±6 14 Briciiam Young Univehsitv Science Bulletin Type data. Female type from Papago Sag- iiaro National Monument. In the L'. S. National Miisciiin. Diagnosis. Tliis large species wlien fiillv grown averages about 100 mm in length and often attains 115 mm. The carapace is duskv brown c.vcrpt in front of the median eyes, where most of the interocuiar space is vellow. The black median eves lie at the center of a crescen- tric darker marking which margins the pale front portion. Tiie preabdonicn is duskv brown, but the postabdomen and the appendages are yel- low to light yellowish brown. The carapace, which is widelv rounded in front, is evenly and c-oarselv granulated, and similar granulations occur over the seventh segment of the preab- domen and on {portions of the preceding seg- ments. Nearly all keels cm the postabdomen are distinct and granular e.xcept the inferior ventral keels, which are smooth in segments I to III. The telson is thick, covered with long red bristles, and the black sting is ()nJ\- about half as long as the vesicle. The hands of the {>edipalps are weakly keeled and granulated mainlv along the rounded sides. The inner edges of the long fingers bear nine slightlv oblique rows of granular denticles, each row marked by an enlarged granule, and nearby large supernumerarv gnmules, nine on die mo\- able finger and seven on the fixed one. Distribution and abundance. Known from .\riz