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DNIVERSITY OF ILLINOIS
ZOOLOGICAL SERIES
OF

FIELD MUSEUM OF NATURAL HISTORY

Volume 24 CHICAGO, OCTOBER 20, 1943 No. 27

SNAKES OF THE PERUVIAN COASTAL REGION

By Karu P. SCHMIDT
CHIEF CURATOR, DEPARTMENT OF ZOOLOGY

AND

WARREN F. WALKER, JR.
HARVARD UNIVERSITY

The Andes divide Peru into three regions familiar to every
Peruvian as the “costa,” the “sierra,’’ and the ‘“‘montafia.”” These
regions, the desert coast with its numerous oases formed by the
transecting valleys; the sierra with its high plateaus and mountain
ridges extending far above snow line; and the tropical forest region
of the deep valleys and of the connected Amazonian lowland east of
the mountains, are in fact the major phytogeographic and zoogeo-
graphic divisions of Peru. The herpetological fauna of the highland
is extremely limited, with only a single species of snake, Tachymenis
peruviana, traceable above 12,000 feet, together with a common
lizard and a few frogs and toads. The tropical lowland has the rich
and complex fauna of the Amazon Basin, further complicated by
the forms proper to the cloud forest zone at intermediate altitudes
on the eastern side of the Andes. In this region much collecting
remains to be done before an adequate study can be made even of
creatures as relatively conspicuous as the snakes. The snake fauna
of the coastal region, though somewhat impoverished in species, is
of great interest, since the species and subspecies are with few
exceptions endemic. In view of the relative simplicity of the coastal
fauna, and with the accumulation of considerable collections from
coastal Peru in Field Museum and in the Museum of Comparative
Zoology, we feel that a review of the snakes of this faunal region
may be a useful preliminary to further studies on the amphibians
and reptiles of Peru.

In addition to a summary of the literature and an attempt to
disentangle the nomenclature of the coastal forms, we here report

No. 533 297

| NAT.
HST,

298 FIELD MUSEUM OF NATURAL HISTORY—ZOOLOGY, VOL. 24

on two considerable collections from the Peruvian coast. The
first of these was assembled by Dr. Axel A. Olsson while stationed at
Negritos as geologist for the International Petroleum Company,
with some increments from Mr. E. W. MacCormack, and more
recently from Mrs. Harriet Frizzell, also of Negritos. The second
consists of an accumulation of preserved snakes presented to Field
Museum’s Magellanic Expedition by Sr. Constante Larco Hoyle on
the occasion of a visit of the senior author to the Hacienda Chiclin
(north of Trujillo) in 1989. A few additional specimens from the
coastal region were received from other sources as results of the
continued interest of Mr. Colin C. Sanborn, also of the Magellanic
Expedition of 1939. Mr. Sanborn collected at Chucurapi, the
hacienda of the Romana family near Mollendo, in 1939, and in the
little-known Ica region in 1942. A single small snake of the genus
Leptotyphlops was presented by Mr. Bruce A. Hertig, of Lima, with
several other additions to the collection from Dr. Marshall Hertig,
of the Instituto Nacional de Higiene y Salud Pablica, in Lima.

The collections of snakes lent to Field Museum for study by
the University of Arequipa have been reported upon by the present
authors. This collection makes available a considerable number of
specimens from the southern portion of the coastal region of Peru.
Finally, the junior author has had the advantage of examining all
of the Peruvian collection at the Museum of Comparative Zoology,
a collection which has been augmented recently by specimens
received from Mr. W. F. Walker, Sr., of Oroyo, Peru, and from
Messrs. J. A. Griswold, Jr., and G. P. Gardner, obtained on their
expeditions to Peru.

The coastal region of Peru may be defined for the purpose of the
present paper as the coastal drainage extending from the Ecuadorean
border to Chile, and from the Pacific coast to the crest of the western
cordillera. The Catamayo Valley, extending into the Ecuadorean
Department of Loja, the low passes of the Cordillera Occidental in
Cajamarca at the north, and the southwestern continuation of the
coastal desert into Chile, make necessary some consideration of
these outlying areas in the discussion of various species in our list.

The Hispanic Map published by the American Geographic
Society indicates that there are three passes over the western
cordillera-near the Ecuadorean border of Peru somewhat below
10,000 feet elevation, and various passes between coastal Piura
and Lambayeque and Andean Cajamarca at less than 8,000 feet.
These passes apparently explain the presence of some non-endemic

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Fic. 26. Map of Peru, showing localities mentioned in the text.

300 FIELD MUSEUM OF NATURAL HISTORY—ZOOLOGY, VOL. 24

forms of Amazonian or Ecuadorean origin in the northern part of
the coastal area and also throw light on the transgression of certain
elements of the coastal fauna into the arid northern portion of
the Marafion Valley. Farther south the passes are at fourteen to
sixteen thousand feet, well above the altitude reached by any species
of the coastal fauna proper. This stupendous mountain barrier is
not again transgressed by reptiles of the lowland east of the Andes
until, at the south, the lake region of southern Chile again provides
passes at low altitude.

The Peruvian coastal region is one of the most barren areas in
the world, much of it rock and sand desert, extending for miles
without visible plant or animal life. It contrasts strongly with the
Sonoran desert in southwestern North America, familiar to North
American biologists, with its wealth of conspicuous plants and
animals adapted to desert conditions through age-long evolution.
Our Sonoran desert is literally the headquarters of the reptilian fauna
of a continent, with numerous forms exhibiting remarkable and
extreme adjustment to desert conditions. In the Peruvian desert,
the reptiles form a mere appendage to the rich reptilian fauna of
South America as a whole, and in spite of the endemism of numerous
species, it seems clearly to be a recent desert, in which there has not
been time for the evolution of specifically xerocole types.

The most remarkable botanical feature of coastal Peru, the rich
seasonal flora of the ‘‘lomas,’’ which depends on concentration of
the coastal fogs in certain slopes and in certain valleys, appears to
have no associated amphibians or reptiles. There are considerable
botanical differences between the Piura region and the coastal desert
farther to the south. The most useful account of the phytogeography
of Peru appears to be that of Weberbauer (1922, 1936).

Much of the interest of the Peruvian coastal fauna and flora
lies in its linear extent from north to south; the biota is richest in
Piura at the north, becoming gradually impoverished to the south,
where the coastal plain is all but pinched out between the mountains
and the sea in northern Chile. In this region only a minimum of
land life persists. To the south of Antofagasta, a scrub vegetation
develops, essentially with only an impoverished desert fauna. The
characteristic Peruvian lizard Tropidurus peruvianus persists on
the coastal strip and the common highland snake of Peru (Tachy-
menis peruviana) descends to low altitudes in central Chile. In
southern Chile, where the humid evergreen forest begins, there is
a radical faunal change, with numerous endemic genera of frogs,

1943 PERUVIAN SNAKES—SCHMIDT AND WALKER 301

though none of snakes. It is evident, even from our necessarily
limited studies, that a systematic survey of the coastal fauna
through its 2,500-mile range from north to south would disclose
numerous variation clines, the establishment of which is necessary
to any definitive taxonomic arrangement of the elements compos-
ing the fauna.

LIST OF LOCALITIES

The localities mentioned in the text are shown on the accom-
panying map. A list of the coastal localities from which specimens
have been examined follows:

Arequipa: The vicinity of Arequipa, capital of the Department of Arequipa,

elevation 7,500 feet. Arid slopes, a semi-desert except in irrigated valley
bottoms.

Bayovar: A port on the southern shore of the Bahia de Sechura, Department
of Piura.

Cajamarquilla: Adobe ruins in the Rimac Valley a few miles inland from Lima,
Department of Lima. Matted bromeliad vegetation.

Chiclin: A sugar-producing hacienda between Trujillo and Chicama, Depart-
ment of Libertad. Irrigated cane fields and pastures, surrounded by
sandy desert toward the coast and by stony pavement desert farther
inland.

Chimbote: A port near the mouth of the Rio Santa at the northern boundary
of the Department of Ancash.

Chongollapi: A village at the desert border in Piura.

Chosica: A resort town above Lima, in the Rimac Valley, at an elevation of
2,800 feet, Department of Lima.

Chucurapi: A sugar hacienda near Mollendo, in the Department of Arequipa.

Ica: A considerable metropolis inland from the port of Pisco, in a broad allu-
vial valley.

Jequetepeque: A valley in the Department of Libertad, entering the sea near
Pacasmayo.

Lima: Capital of Peru, Department of Lima, on the irrigated alluvial plain
of the Rimac River.

Majes Valley: A long, well-watered valley north of the Vitor Valley, Depart-
ment of Arequipa.

Negritos: A port in northern Piura just south of Talara.

Pacasmayo: The port of entry for Cajamarca in the northern part of the
Department of Libertad.

Quebrada Montero: An arroyo in the oil-field region, Department of Piura.

Quebrada Parinas: An arroyo emptying into the ocean at Parinas just south
of Negritos, Department of Piura.

Quebrada Paxul: An arroyo in the oil-field region, Department of Piura.
Quebrada Sal Grande: An arroyo in the oil-field region, Department of Piura.
Quebrada Seca: An arroyo in the oil-field region, Department of Piura.

302 FIELD MUSEUM OF NATURAL HISTORY—ZOOLOGY, VOL. 24

Surco: A small town at an elevation of about 6,000 feet, in the Rimac Valley
below Matucana, Department of Lima.

Talara: The port and headquarters of the International Petroleum Company,
Department of Piura.

Tambo: A small town on the Rio Tambo, in the southern part of the Depart-
ment of Arequipa.

Toquepala: A mining camp at an elevation of 8,000—10,000 feet, east of the
city of Moquegua, Department of Tacna.

Vitor Valley: A valley crossing the coastal desert of the Department of
Arequipa below Arequipa.

Other localities from which specimens have been examined
include especially Perico, the Rio Marafion, and Bellavista, in the
Marajfion Valley (eastern Cajamarca), where the late G. K.
Noble made collections for the Museum of Comparative Zoology
in 1916.

Specimens of coastal species in the collections of the University
of Arequipa recorded as from ‘“‘Selvas de Sandia” and ‘‘Madre de
Dios” appear to bear erroneous data (Schmidt and Walker, 1948,
p. 284).

Serpentes
Leptotyphlopidae

Leptotyphlops rufidorsus Taylor

Leptotyphlops rufidorsum Taylor; Univ. Kans. Sci. Bull., 26, p. 588, fig. 2,

1940—Lima, Peru.

A medium-sized Leptotyphlops, without cephalic or caudal spots,
with a median dorsal brownish band covering three scale rows and
the adjacent half scale rows; dorsal scales about 260.

Known only from the type locality and from Chiclin, Libertad,
as here reported, thus possibly characteristic of the central portion
of the desert region. |

A single specimen, No. 34805, from Chiclin, Libertad, has dorsal
scales 256, caudals 16, scales around body 14, around mid-tail 10;
length 241, tail 12; diameter of body contained in total length
about 40 times. Supraocular and labial separating rostral from
ocular on both sides. Coloration in close agreement with Taylor’s
description.

We have read Werner’s description of Glauconia albifrons var.
rubrolineata (Werner, 1901, p. 6), said to be from Lima, with atten-
tion.. It does not appear to refer to any of the species here recorded,
and, as remarked below (p. 313), the type locality may well be
erroneous.

1943 PERUVIAN SNAKES—SCHMIDT AND WALKER 303

Leptotyphlops subcrotillus Klauber
Leptotyphlops subcrotilla Klauber, Trans. San Diego Soc. Nat. Hist., 9, pp.
59-66, fig. 2, 1939—Grau Tombes, northern Peru [=Grau, Tumbez].
A small slender worm snake of the albifrons group, with a white
spot on the rostral and on the caudal spine; dorsal scales from
rostral to tail spine about 330.

Known only from the type locality and from Chiclin, Libertad,
as here reported, thus apparently ranging through the northern
desert region.

Two specimens, Nos. 34267 and 34304, from Chiclin, Libertad,
agree excellentiy with Klauber’s description. The dorsal scales
number respectively 325 and 324; scale rows 14; scales around
mid-tail 10; total length and tail length 137 and 6, and 184 and 8;
diameter of body contained in total length 70 to 90 times.

Leptotyphlops melanurus sp. nov.

Type from Chiclin, Libertad, Peru. No. 34269 Field Museum
of Natural History. Presented to Magellanic Expedition of Field
Museum, November, 1939, by Sr. Constante Larco Hoyle.

Diagnosis.—A small slender worm snake, nearly uniform in
coloration, not distinctly lineate; no caudal spot, rostral spot
occasionally present; dorsal scales 395; ocular shield in contact
with the nasal.

Description of type.-—Body slender, head very little widened,
tail about three times as long as its diameter, ending in a small
spine-bearing scale. Snout rounded, projecting.

Rostral narrowed posteriorly, extending backward barely to the
eye; upper portion of nasal considerably larger than lower; ocular
broadly in contact with nasal; ocular widest at eye-level, eye dis-
tinct, at anterior border of ocular supraoculars wider than long,
posterior larger than anterior, both larger than the median series
- of scales; third scale of median series largest, followed by a narrower
scale with a small scale on each side, while the fifth scale is wider,
though not longer, than the third; scales following the fifth gradually
narrowed to the uniform mid-dorsal series; parietals about as wide
as posterior supraoculars; chin shields small.

The scales are in 14 rows throughout the length of the body, 10
around the middle of the tail. Dorsal scales from rostral to caudal
spine 395; caudals 18.

304: FIELD MUSEUM OF NATURAL HISTORY—ZOOLOGY, VOL. 24

General color brown, a little lighter beneath, the outlines of the
scales lighter; a light spot on the rostral, none on the tail; upper
head shields all with light pores.

Measurements of type.-—Length 135; tail 6; diameter of body 2.

Notes on paratype.—The single paratype, No. 34268, obtained
with the type at Chiclin, measures only 91 mm., tail 5. It agrees
almost exactly with the type, with dorsal scales 396 and caudal 20.

Range.—Known only from type locality.

Leptotyphlops tessellatus Tschudi
Typhlops tessellatum Tschudi, Fauna Peruana, Herp., p. 46, 1845—Lima.

Two specimens of a small Leptotyphlops of the albifrons type from
Lima may be referred with little hesitancy to Tschudi’s species.
One of these was collected and presented by Mr. Bruce A. Hertig,
the other was collected in the wall of an old adobe house in Lima
by Mr. Felix Woytkowski, a well-known collector of Peruvian
insects. Leptotyphlops tessellatus is here redescribed in some detail
for comparison with recent descriptions of species of this genus.

Diagnosis.—A small worm snake with lineate pattern, darker
on the upper half of the body, and with white spot present on rostral
and tail spine. Ocular separated from nasal by supraocular and
labial; dorsal scales about 260.

Description (No. 85097).—Body slender, head scarcely wider
than body, tail three and one-half times as long as its diameter,
ending in a rather large pointed scale. Snout rounded, projecting.

Rostral sharply narrowed posteriorly, extending backward
barely to the level of the eye; upper and lower portions of nasal
subequal; ocular separated from nasal by a contact of the supra-
ocular with the first labial; eye distinct at upper anterior corner
of the ocular; anterior supraoculars a little smaller than posterior,
directed obliquely forward and outward; posterior supraoculars
about equal to parietals; median scales very narrow, fifth behind
rostral widest.

The scales are in 14 rows throughout; 10 scales around middle
of tail. Dorsal scales from rostral to tail spine 261; caudals 17.

General color brown, lighter on the edges of the scale rows,
producing a lineate appearance; seven dorsal rows darker than the
seven ventral; a light spot on the rostral and lower portions of the
nasals, and one covering the entire tail spine and two adjacent

1943 PERUVIAN SNAKES—SCHMIDT AND WALKER 805

scales; upper head shields all with light pores. Length 90; tail 5;
diameter of body 2.

The second specimen in our collection (No. 36726) measures 102;
tail 6; diameter of body 2. It has 262 dorsal scales from rostral to
tail spine.

Range.—Known only from the coastal area of north-central
Peru near Lima.

Remarks.—There appears to be no doubt that the Leptotyphlops
albifrons of authors is an omnium gatherum of species of varying
degrees of distinctness. In view of the generally endemic nature
of the Peruvian coastal fauna, it is extremely unlikely that true
albifrons, an Amazonian species, should occur there. It is never-
theless surprising that four fully distinct species of Leptotyphlops
should occur in this faunal area.

The reference of the present form to tessellatus is based primarily
on the fact that the type locality is Lima, where Tschudi obtained
three specimens from houses, so that it appears to be reasonably
abundant. Darwin obtained a specimen from Lima, recorded by
Boulenger (1898, p. 36), which presumably belongs here, as may a
specimen from Chimbote reported by Cope (1877, p. 35).

Boidae

Constrictor constrictor ortonii Cope
Boa ortonii Cope, Proc. Amer. Phil. Soc., 17, p. 35, 1878—Chilete, near
Pacasmayo.

Constrictor constrictor Dunn, Proc. Biol. Soc. Wash., 36, p. 186, 1923—Perico

and Rio Marafion.

A medium-sized boa constrictor, pale in coloration in association
with its desert habitat, related to C. c. imperator in the relatively
low number of dorsal seale rows. It differs from imperator of Central
America and northwestern South America in having a higher number
of ventrals and in its lighter and more sandy ground color.

The range of C. c. ortonii appears to extend from Perico and the
upper Marafion Valley to Piura and south to Libertad, in the arid
region of northwestern Peru.

The two specimens in Field Museum, No. 8360, from Parinas
Valley, Piura, and No. 34301, from Chiclin, Libertad, are both
males, with dorsal scales 57-62 at mid-body, ventrals 250-251, and
caudals 46-55. The five specimens collected by the late G. K.
Noble for the Museum of Comparative Zoology, Nos. 17664 and

306 FIELD MUSEUM OF NATURAL HISTORY—ZOOLOGY, VOL. 24

18960, from Perico, and Nos. 18977-18979 from the Rio Marafion,
include three males and two females. The total ventral range in
males is 246-252, and caudals 46-59. In two females, the ventral
range is 246-248, caudals 49-51. The maximum of dorsal scale
rows in both sexes is 72.

The separation of the orbital scales from the labials in the type,
thought by Cope to distinguish this form, holds in several of our
specimens, but is not diagnostic.

Colubridae!

Dryadophis boddaertii heathii Cope
Drymobius heathii Cope, Journ. Acad. Nat. Sci. Phila., 8, p. 179, 1876—Valley
of Jequetepeque; Proc. Amer. Phil. Soc., 17, p. 34, 1877.
Herpetodryas boddaertii var. heathiit Boettger, Ber. Senck. Ges., 1889, p. 313,
1889.
Dryadophis heathit Stuart, Misc. Publ. Mus. Zool. Univ. Mich., 49, p. 77,
1941.

The common Dryadophis of the Peruvian coastal region is a
medium-sized grayish-colored ground snake, with a light lateral
stripe on each side. It is distinguishable from the race D. b. bod-
daertit of the Amazon Basin by the position of the lateral stripe on
scale rows 4, 5, and 6 anteriorly and 3, 4, and 5 posteriorly, instead
of on 4 and 5 only. The young are crossbarred.

The subspecies heathii is confined to the Peruvian coastal region,
ranging from Libertad to Lima and from sea level to at least 6,000
feet altitude.

The specimens examined in Field Museum collections are No.
5706, from Pacasmayo, collected by W. H. Osgood and M. P.
Anderson in 1912; Nos. 34288, 34296-34299, 34312, and 34316-19,
from Chiclin; and No. 38108, collected at Surco, and presented by
Dr. Marshall Hertig.

In this series, four male specimens have ventrals 176-185 and
caudals 103-107; five females have ventrals 189-192 and caudals
103-108, thus altering Stuart’s diagnosis of heathit by a slight
lowering of the range of caudals and a considerable lowering of
that of the ventrals. This is not surprising, in view of the small
number of specimens of this form previously available. The color-

1Jan’s record of Rabdosoma badium multicinctum (Icon. Gén. Ophid., Livr.

10, pl. 4, fig. 5, 1865), from Lima, is not included. It is doubtless based on a
transported specimen.

1943 PERUVIAN SNAKES—SCHMIDT AND WALKER 307

ation of the under surface is not always immaculate; it may be
dotted with gray, and the limit of the encroachment of the dorsal
ground color upon it is faintly marked by a narrow whitish line on
each side. These changes tend to reduce the differences between
heathti and boddaerti, and we have accordingly placed heathii as a
race of boddaertii.

The series before us includes four specimens from Chiclin with
the typical juvenile crossbarred coloration of the boddaertit group
(Stuart, 1941, p. 21). A fifth specimen, No. 38108, a male, from
Surco, Lima, taken at an altitude of 6,000 feet, measures only 275
mm. in body length, but has no trace of the juvenile markings.
We agree with Stuart (l.c., p. 73) in suspecting that there may be
a dwarfed Andean race, or that both b. heathii and b. boddaertii
may be dwarfed at altitudes above their normal range.

Stuart (l.c., p. 70) reports a specimen from Huaraz, in the
coastal drainage, as boddaerti: boddaertii. On geographic grounds,
we question this allocation of the specimen.

Drymarchon corais melanurus Duméril and Bibron
Spilotes melanurus Duméril and Bibron, Erp. Gén., 7, p. 224, 1854—Mexico.

Spilotes pullatus dichrous Dunn, Proc. Biol. Soc. Wash., 36, p. 186, 1923
(not of Peters, part).

Drymarchon corais melanurus Ruthven, Misc. Publ. Mus. Zool. Univ. Mich.,
8, p. 65, 1922; Parker, Ann. Mag. Nat. Hist., (11), 2, p. 448, 1938.
Drymarchon corais melanurus is a large terrestrial snake, charac-
terized by black coloration on the head and neck and on the posterior
part of the body and tail, with the dorsal scales in slightly oblique
rows.

Its presence in coastal Peru rests on the somewhat dubious record
from Chongollapi, Piura (Dunn, 1928, p. 186), but further records
from the Catamayo Valley in Ecuador (Parker, 1938) make its oceur-
rence in the arid coastal region probable.

We do not find characters to differentiate this form from the
Mexican and Central American melanurus, but it is evident that
the Peruvian and Ecuadorean population affords a taxonomic
problem, especially in view of the various races of corais in Mexico
demonstrated by Smith (1941, p. 466). The Chongollapi specimen
has 214 ventrals and 75 caudals. It apparently represents the
southern extreme of a trend toward lower numbers of ventrals,
which has been pointed out by Smith.

308 FIELD MUSEUM OF NATURAL HISTORY—ZOOLOGY, VOL. 24

We are not convinced of the desirability of nomenclatural
changes on the grounds offered by Smith (1941, p. 474); see Harper
(Copeia, 1942, p. 180) for the contrary argument. It is evident
that a malevolent person, applying the interpretation of the rules
as followed by Smith, could upset a very large proportion of current
names.

Dromicus angustilineatus sp. nov.
Dromicus chamissonis Schmidt and Walker, Field Mus. Nat. Hist., Zool. Ser.,
24, p. 283, 1943 (in part, not of Wiegmann).

Type from Toquepala, Tacna, Peru. No. 45908 Museum of
Comparative Zoology. Adult male, collected in April, 1938, by
W. F. Walker, Sr.

Diagnosis.—A Dromicus allied to chamissonis of coastal Chile,
but with ventrals 204-217 (maximum known in chamissonis 200)
and with a narrow dark mid-dorsal line instead of the wider band
of the Chilean form.

Description of type-——Form of body typically colubrid; rostral
broader than deep, just visible from above; internasals shorter.
than prefrontals; frontal twice as long as broad, longer than its
distance from the tip of the snout, as long as the parietals; supra-
oculars nearly as wide as the frontal; nasal divided; loreal longer
than deep; preocular single, reaching the upper surface of the head,
but not in contact with the frontal; 2 postoculars on each side;
temporals 1-2 on each side; upper labials 8, fourth and fifth entering
the eye; lower labials 10, six in contact with the chin shields; pos-
terior chin shields longer than the anterior; dorsal scales smooth,
with single apical pits, scale reduction formula 19-17-15, the scale
rows at mid-body 19; ventrals 204; anal divided; caudals 111.

Posterior maxillary teeth enlarged. Hemipenis bifurcate,
with bifureate sulcus and with tips of the bifurcations calyculate.

A mid-dorsal dark line three scales wide on the nape soon nar-
rowing to the width of the mid-dorsal scale row; a light gray band
extending to the fifth scale row, bounded below by a sharply marked
though somewhat interrupted black line on the middle of that scale
row; a more obscure dark line along the middle of the light gray
band; darker gray on the sides, merging below into the lighter
ventral color; head brownish above, with a dark streak from the
rostral through the eye and across the temporals to become con-
tinuous with the lateral darker gray band.

1943 PERUVIAN SNAKES—SCHMIDT AND WALKER 309

Notes on paratypes.—In addition to M.C.Z. No. 45907 from the type
locality, we have examined six specimens in the collection of the
University of Arequipa (Schmidt and Walker, 1948, p. 283), of which
four have now been accessioned by Field Museum as Nos. 40035—
40088. Three of these, F.M.N.H. Nos. 40037-40038 and U.A. No.
141, are said to be from Madre de Dios, in Amazonian Peru; this
we regard as a mistake caused by confusion of data. The remaining
paratypes are from Tambo, F.M.N.H. No. 40035; from the vicinity
of Arequipa, F.M.N.H. No. 40036; and from the Vitor Valley, U.A.
No. 10. This series of specimens, though much faded from exposure
to light, agrees well with the type. Two have 21 scale rows on the
neck; one has upper labials 7-8, and one has upper labials 9-9;
anterior temporals 2 in two specimens; four males have ventrals
195-204, caudals 111-125; three females have ventrals 205-217 and
caudals 110-111. The narrow black lines of the back tend to be
broken into series of spots, but are distinct in six paratypes; in
M.C.Z. 45907 they have disappeared entirely.

Measurements.—Type 584; tail 161. Largest female (U.A. 10)
891; tail 280.

Range.—Southwestern Peru, from near sea level to about 10,000
feet.

Remarks.—It seems evident that Dromicus angustilineatus is
directly related to D. chamissonis of Chile, which it replaces in
southern Peru, and from which it differs in its higher number of
ventrals, and in the narrow dorsal line, instead of the broad dorsal
band of the Chilean species.

Dromicus tachymenoides sp. nov.

Type from Chucurapi (near Mollendo), Department of Arequipa,
Peru. No. 34261 Field Museum of Natural History. Adult female,
collected in October, 19389, by Colin C. Sanborn.

Diagnosis.—A Dromicus allied to D. chamissonis of Chile and
to angustilineatus described above; differing from the former in its
higher number of ventrals (202-220) and from the latter in having
a spotted coloration, without longitudinal lines and bands.

Description of type-—A snake of typical colubrid proportions;
rostral nearly as deep as broad, visible from above, internasals
shorter than the prefrontals, frontal nearly twice as long as broad,
a little longer than its distance from the end of the snout, and
nearly as long as the parietals; supraoculars large, as wide as the

310 FIELD MUSEUM OF NATURAL HISTORY—ZOOLOGY, VOL. 24

frontal posteriorly; nasal divided; loreal nearly twice as long as
deep; preocular single, extending to the upper surface of the head,
not in contact with the frontal; 2 postoculars; temporals 2-2 on
each side; supralabials 10 on the left side, fifth and sixth entering
the eye, 8 on the right, fourth and fifth entering the eye; several
labials horizontally divided; lower labials 11-18, 7 and 6 in contact
with the chin shields. Dorsal scales smooth, with single apical pit,
scale rows 19 at mid-body, 23 immediately behind the head, full
formula 23-21-19-17-15; ventrals 202, anal divided, caudals 107.

Posterior maxillary teeth enlarged, not grooved.

General coloration light gray (superficial epidermis lacking),
with black punctulation on most scales; two parallel rows of paired
black or dark gray spots along the back, the pairs uniting anteri-
orly to form transverse bars on the neck; venter mottled gray and
yellow. Head brownish gray above, with a dark gray band from the
rostral through the eye to the neck, not in contact with the anterior
dark crossbars; labials and chin yellowish, slightly mottled with
gray. ;

Measurements.—Total length 1,055; tail 300.

Notes on paratypes.—Two paratypes received from the Uni-
versity of Arequipa agree excellently with the type in scale and color
characters. Both are females; F.M.N.H. No. 40033 is without data;
U.A. No. 15 is said to be from the “Selvas de Sandia,” a locality
that we regard as an error in labeling. The former specimen has
ventrals 220, caudals 106; in the latter the ventrals can not be
counted; it has caudals 102. The edges of the ventrals are dotted
with black in both specimens. A third paratype, M.C.Z. 45940,
is from Toquepala. It agrees in coloration but has a somewhat
broader rostral, longer frontal, and shorter loreal than the type; it
has ventrals 216, and caudals 95.

Range.—Known only from southern coastal Peru, where it occurs
together with angustilineatus, from sea level to ten thousand feet
altitude.

Remarks.—It will be seen that the numbers of ventrals and
caudals in tachymenoides are little different from those in angusti-
lineatus; the species appears to be adequately distinguished by its
spotted and crossbarred color pattern, which bears a general resem-
blarice to that of Tachymenis peruviana. It is obvious that the
range and habitat of Dromicus angustilineatus and of D. tachy-
menoides afford unsolved geographic problems.

1943 PERUVIAN SNAKES—SCHMIDT AND WALKER 311

Boigidae

Leptodeira larcorum sp. nov.
Sibon annulatum (not of Linnaeus) Cope, Proc. Amer. Phil. Soc., 17, p. 33,
1877—Chimbote Valley.
Leptodeira annulata Dunn, Proc. Biol. Soc. Wash., 36, p. 186, 1923.

Type from Chiclin, Libertad, Peru. No. 34802 Field Museum
of Natural History. A male specimen, presented to the Magellanic
Expedition of Field Museum by Sr. Constante Larco Hoyle, in 1939.

Diagnosis.—A Leptodeira resembling L. rhombifera of Central
America and northwestern South America in having vertebral and
paravertebral scale rows little if at all enlarged, and thus differing
from L. annulata annulata; differing from rhombifera in having a
higher number of ventrals, 175-184 versus 158-178, and caudals,
78-91 versus 64-84, and in the strong tendency for the dorsal spots
to fuse into a zigzag line (in the latter respect resembling annulata
annulata; Dunn, 1936, p. 691).

Description of type-—A snake with large head, distinct from the
neck, with a large eye; body slightly compressed. Rostral much
broader than high, scarcely visible from above; internasals shorter
than the prefrontals; frontal one-third longer than broad, as long
as its distance from the end of the snout, shorter than the parietals;
nasal divided; loreal slightly longer than high; a large preocular, in
contact with the frontal; a small inferior preocular formed by divi-
sion of the third labial; 2 postoculars; temporals 1-2, with a small
additional anterior temporal cut off from the seventh labial; upper
labials 8, the fourth and fifth entering the eye; lower labials 10, six
in contact with the chin shields; posterior chin shields slightly longer
than anterior; dorsal scales smooth, simplified formula 19-21-15;
ventrals 184, anal divided, caudals 91.

Head grayish brown with a butterfly-shaped darker marking on
the parietals and occiput, and a dark band from snout to angle of
mouth; grayish brown above, with alternating paravertebral blotches
that tend to fuse into a zigzag dorsal band; a lateral row of alter-
nating spots, with still smaller spots on the first and second scale
rows; lateral spots disappearing on the tail; uniform yellow beneath,
with faint brown markings on the chin and lower labials.

Measurements of type.—Total length 630; tail 172.

Notes on paratypes.—Twenty-three specimens in addition to the
type are referred to this species: F.M.N.H. Nos. 34806-34311, from
the type locality, presented by Sr. Constante Larco Hoyle; M.C.Z. Nos.

312 FIELD MUSEUM OF NATURAL HISTORY—ZOOLOGY, VOL. 24

17412-17416 from Perico, and 17454-17465 from Bellavista, collected
by G. K. Noble in 1916. In this series, in excellent agreement with
the type in coloration, the preocular is in contact with the frontal in
about half the specimens, and several agree with the type in the
presence of a small lower preocular, and in the small supernumerary
anterior temporal.

There is some geographic variation in the caudals in females,
not discernible in the smaller series of males, as shown below:

Number of
specimens Sex Ventrals Caudals
b merle 065 tert 3 ee 178-184 88-91
aaa aig { 3 Q 183-188 75-82
Caj ego h hs SF 2 re i 178-182 89-91
ee re { 10 Q 175-184 78-84

The largest paratype, F.M.N.H. No. 34806, measures 905;
tail 204.

Range.—Northern coastal Peru, extending into the arid parts of
the Marafion Valley.

Remarks.—The new form is named for the brothers Rafael, Con-
stante, and Xavier Larco Hoyle, who together manage the Hacienda
Chiclin, where their régime is characterized by modern and ingenious
agricultural methods, social consciousness, and a wide interest in
general science. Thus it was not an accident that they should have
accumulated the considerable collection of snakes presented by them
to the Magellanic Expedition of Field Museum and here reported
upon.

Oxyrhopus fitzingeri fitzingeri Tschudi
Siphlophis fitzingert Tschudi, Fauna Peruana, Herp., p. 56, pl. 8, 1845—coast
of Peru.

Oxyrhopus fitzingeri Jan, Elenco Syst. Ophid., p. 93, 1863; Icon. Gén.
Ophid., Livr. 35, pl. 5, fig. 1, 1870; Boulenger, Cat. Snakes Brit. Mus.,
3, p. 108, 1896; Werner, Abh. Mus. Dresden, 9, No. 2, p. 8, 1900 (part).

Pseudoboa fitzingeri Amaral, Proc. U. S. Nat. Mus., 67, art. 24, p. 12, 1925
(part)—Verrugas Canyon.

Oxyrhopus fitzingeri fitzingert is a medium-sized snake with the
strong musculature of a constricting species, characterized by singu-
larly irregular dark brown markings on a yellowish ground color.
These spots may cover only a single scale, or may be confluent into
blotches or zigzag lines. It is distinguished from its northern sub-
species (described below) by a much higher number of ventrals and

1943 PERUVIAN SNAKES—SCHMIDT AND WALKER 313

caudals. It is a common snake of the arid coastal region from sea
level to at least 6,000 feet altitude in the Rimac Valley.

We have examined a single specimen in Field Museum, No.
34361, from Surco, collected by Marshall Hertig in 1938. This
specimen, a female, has ventrals 227 and caudals 94; by division
of anterior labials, there are 10 upper labials on each side; preoculars
2 on the left, 1 on the right side; length 714, tail 157.

Search of the literature discloses two additional female specimens
from the Rimac Valley or presumably so, and these agree with our
Sureo specimen and with the type in number of ventrals. In the
type the ventrals number 236 and caudals 77, and it undoubtedly
is a female; the specimen recorded by Boulenger has ventrals 232 and
caudals 81; and one from Verrugas Canyon (see Hertig, 1942, pt. III,
p. 24 and pl..1), collected by C. H. T. Townsend, has ventrals 227
and caudals 79. The senior author has elsewhere called attention
to the confusion of data in the Dresden Museum collection
reported upon by Werner (1901). Much of the Chanchamayo
material in the collection undoubtedly was received from the Chan-
chamayo near La Merced in the Department of Junin, the residence
of Carlos Schunke, a dealer in museum specimens; but this could
searcely have been the locality where Oxyrhopus fitzingeri and
Micrurus tschudit were collected. Such confusion of data in
collections received from foreign correspondents is a not infrequent
occurrence. The Dresden collection includes specimens with both
high and low numbers of ventrals; but as these are not sexed
they cannot be assorted, even arbitrarily, to the two subspecies of
fitzingeri.

Oxyrhopus fitzingeri frizzelli subsp. nov.

Oxyrhopus fitzingeri Cope, Journ. Acad. Nat. Sci. Phila., 8, p. 177, 1876—
Jequetepeque; Proc. Amer. Phil. Soc., 17, p. 33, 1877—-Chimbote; Boettger,
Ber. Senck. Ges., 1889, p. 314, 1889—Pacasmayo; Peracca, Bol. Mus.
Zool. Torino, 19, No. 465, p. 14, 1904—Puntilla Santa Elena, Ecuador.

Clelia fitzingeri Dunn, Proc. Biol. Soc. Wash., 36, p. 186, 1923—Chongollapi,
Piura, Peru.

Pseudoboa fitzingeri Amaral, Proc. U. S. Nat. Mus., 67, Art. 24, p. 12, 1925—
part, Piura; Parker, Ann. Mag. Nat. Hist., (11), 2, p. 444, 1938—Cata-
mayo Valley, Ecuador.

Type from Negritos, Piura, Peru. No. 35997 Field Museum of

Natural History. A male specimen, collected in 1939 and presented
by Harriet E. and Don L. Frizzell.

314 FIELD MUSEUM OF NATURAL HISTORY—ZOOLOGY, VOL. 24

Diagnosis.—An Oxyrhopus with the typical fitzingeri coloration,
but with a much lower number of ventrals, 202-207 in females,
contrasted with 227-236 in four female fitzingeri; and of caudals
57-69 instead of 77-94.

Description of type—A relatively slender snake with small
pointed head scarcely distinct from the neck. Rostral wider than
high, well visible from above; internasals much smaller than pre-
frontals, their suture less than half that of the prefrontals; frontal
a little longer than wide, shorter than the parietals; loreal twice as
long as high; preocular single, widely separated from the frontal,
postoculars 2 on each side; upper labials 8-8, the fourth and fifth
entering the eye; lower labials 9-9.

General ground color pale yellow, the venter and lowermost
scale rows immaculate; back heavily and irregularly marked with
dark brown spots, mostly following scale outlines; top of head
mottled with dark on a paler brown ground color; a solid dark
brown nuchal mark nearly as long as the head.

Measurements of type.—Total length 647; tail 131.

Notes on paratypes.—Six paratypes are available for the estab-
lishment of O. f. frizzelli: An additional specimen, No. 35998,
collected by V. J. Molonoy and Don L. Frizzell at the mouth of the
Quebrada Paxul, Amotape Mountains, Piura; No. 5665, collected
by M. P. Anderson at Chimbote, Ancash, in 1912; No. 11014,
collected by A. A. Olsson at Bayovar, Piura; Nos. 34284 and 34300,
presented by Sr. Constante Larco Hoylein 1939;and M.C.Z. No. 17383,
collected by G. K. Noble at Chongollapi, Piura, in 1916. These are
in close agreement with the type. The last-named specimen has
the loreal fused with the prefrontal on both sides. With these may
be associated the U. S. National Museum specimen from Piura
collected by C. H. T. Townsend; two British Museum specimens
recorded from the Catamayo Valley in Ecuador by Parker; and two
specimens reported by Peracca from Puntilla Santa Elena, in ‘‘a
dry region of the coast”? of Ecuador, west of Guayaquil; with the
type, there are five female and seven male specimens. Ventrals .
and caudals in this series may be compared with those of the typical
race:

Number of

Subspecies specimens Sex Ventrals Caudals

, FRCENOENE Ss eh PS 4 Q 227-236 77-94
; : Ff fof 188-206 68-77

Pes ITASROUG ston See { 5 9 209-207 57-69

1943 PERUVIAN SNAKES—SCHMIDT AND WALKER 315

Amaral (1925, p. 12) noted the wide difference in ventrals between
the male specimen from Piura and the female from Verrugas Canyon,
supposing this to be a sexual difference. The female specimens now
at hand from northern Peru and adjacent Ecuador make it clear
that a distinct geographic race (with intermediates not yet demon-
strated) is recognizable in this region.

Range.—Coastal Peru from Pacasmayo to Piura, in the adjacent
Catamayo Valley in Ecuador, and in the dry coastal area near
Guayaquil.

Remarks.—The Peruvian and Guayaquil series of five male and
five female specimens forms a compact group with ventrals 197-206
in males and 202-207 in females. Two specimens, both males,
reported by Parker from the Catamayo Valley, indicate a possible
further reduction of ventrals in populations to the northeast, as
these specimens have ventrals respectively 188 and 190.

Tachymenis peruviana Wiegmann
Tachymenis peruviana Wiegmann, Nova Acta Acad. Leop.-Carol., 17, p.
252, pl. 20, fig. 1, 1835—Peru.

Tachymenis peruviana is the common highland snake in Peru,
ranging above 15,000 feet on the plateaus and mountain masses
and extending downward on both sides of the Andes to about 6,000
feet. In Chile it reaches sea level at the latitude of Coquimbo.

The wide range of this species and the large series accumulating
in American museums warrant treatment of this species as a special
problem.

Philodryas elegans rufidorsatus Giinther

Dromicus rufidorsatus Giinther, Cat. Colubrine Snakes Brit. Mus., p. 130,
1858—America (here restricted to northern coastal Peru).

Tachymenis canilatus Cope, Proc. Acad. Nat. Sci. Phila., 20, p. 104, 1868—
Guayaquil.

Lygophis poecilostomus Cope, Journ. Acad. Nat. Sci. Phila., (2), 8, p. 180,
1876—Valley of Jequetepeque.

Dryophylax vitellinus Cope, Proc. Amer. Phil. Soc., 17, p. 33, 1877—Pa-
casmayo.

Dryophylax elegans Cope, Proc. Amer. Phil. Soc., 17, p. 34, 1877.

Tachymenis elegans Boettger, Ber. Senck. Ges., 1889, p. 312, 1889.

Philodryas elegans Boulenger, Cat. Snakes Brit. Mus., 3, p. 1896 (part);?
Werner, Abh. Mus. Dresden, 9, No. 2, p. 9, 1901 (part).

1Boulenger includes Dromicus rufidorsatus in his synonymy of elegans with
the notation “part,’’ but we find no other reference to Giinther’s species in his
catalogue.

316 FIELD MUSEUM OF NATURAL HISTORY—ZOOLOGY, VOL. 24

Philodryas simonsii Boulenger, Ann. Mag. Nat. Hist., (7), 6, p. 185, 1900—
Cajamarca at 9,000 feet.

Philodryas elegans rufidorsatus is a small or medium-sized ter-
restrial snake with a dark vertebral band broken anteriorly into
paired or alternating spots, or into crossbands. This band is sepa-
rated from the light band bordering it on each side by a row of black
dots, which fuse to form a continuous line posteriorly; below this is
a darker lateral band.

This race ranges from the semi-arid areas near Guayaquil,
Ecuador, to the Department of Libertad in Peru, from sea level
to about 9,000 feet altitude.

We have examined twenty specimens: No. 5730, Verdun; No.
8386, Quebrada Sal Grande; Nos. 8887-8388, Quebrada Montero;
9807-9808, Quebrada Seca; Nos. 9776 and 9790, Quebrada Parinas;
and No. 9791, Bayovar—all collected by A. A. Olsson; Nos. 8448-
8449 from Parinas Valley, collected by E. W. MacCormack; No.
38682, Negritos, collected by H. E. Frizzell; all in the Department
of Piura. Eight specimens were presented to the senior author at
the Hacienda Chiclin, Libertad, in 1939.

This considerable series makes possible the partition of elegans
with its complicated synonymy into a northern and a southern race,
essentially paralleling other forms with two subspecies in the coastal
province. The northern form may be redescribed as follows:

Description.—A_ slender, long-headed snake. Rostral much
broader than deep in the adult, nearly as deep as broad in the young;
frontal long and narrow; nasal divided; loreal about as long as deep;
a single preocular which may reach the frontal or be separated from
it to varying degrees; 2 postoculars; temporals 1-1, 1-2, or 1-38,
usually with a small shield cut off from the anterior temporal so
that the temporal formula may appear as 1-1-1, 1-1-2, 1-1-3, or
2-8; upper labials usually fourth and fifth entering the eye, occa-
sionally 9; lower labials usually 10, six in contact with the chin
shields, occasionally 9. Dorsal scale rows 19-17, 19 at mid-body.
Ventrals 188-208, caudals 96-108 in males; 191-212 and 88-96
in females.

Coloration variable, typically with a darker dorsal band bounded
by a lighter one, and with darker sides; head gray above with yellow-
ish markings on the parietals and frontal; a darker grayish streak
extending from the snout, through the eye, across the temporals
and last upper labial to become continuous with the darker lateral
band; upper and lower labials yellow with gray spots; venter yellow,

1943 PERUVIAN SNAKES—SCHMIDT AND WALKER $17

usually regularly spotted with brown or gray, occasionally uniform.
One specimen completely uniform in coloration, like the type of
vitellinus; two others approach uniformity of coloration.

Remarks.—The original description is poor and without exact
locality. The fact that this form has been re-described four times
as a new species seems to be related to the variable coloration and
to the differences between the juvenile and adult, as well as to the
fallibility of taxonomists.

Philodryas elegans rufidorsatus has heretofore been confused
with elegans elegans of central and southern Peru. P. e. rufidorsatus
has a somewhat lower number of ventrals and caudals, 17 instead
of 15 scale rows posteriorly, and a somewhat different color pattern,
when a pattern is developed.

Within rufidorsatus we can detect a cline in numbers of ventrals
and caudals from north to south, as in Oxyrhopus fitzingeri.

, Number of
Region : specimens Sex Ventrals Caudals

Philodryas elegans rufidorsatus

Sy |, PAR MMAR SAP a at Oa ets See 5 ou 188-208 99-108
a { 4 g 191-212 88-96
[Thon + SRR tht Ate act OnE EE 4 ou 195-199 96-108
_e { 5 Q 199-207 89-94
Philodryas elegans elegans
] i 6 ot 207-217 112-123
Central and southern Peru { | 3 5 199-208 oid

Philodryas elegans elegans Tschudi
Lygophis elegans Tschudi, Fauna Peruana, Herp., p. 53, pl..6, 1845—Uru-
bamba and Lima (type locality here restricted to Lima).
Dromicus elegans Jan, Elenco Sist. Ophid., p. 67, 1868; Icon. Gén. Ophid.,
Livr. 25, pl. 1, fig. 2, 1867.

Philodryas elegans Boulenger, Cat. Snakes Brit. Mus., 3, p. 133, 1896 (part);
Werner, Abh. Mus. Dresden, 9, No. 2, p. 9, 1901 (part); Amaral, Proc.
U.S. Nat. Mus., 67, Art. 24, p. 15, 1925.

Dryophylax freminvillei Duméril and Bibron, Erp. Gén., 7, p. 1115, 1854—
Guyane and Callao, Peru (type locality here restricted to Callao).

Philodryas freminvillei Jan, Elenco Sist. Ophid., p. 83, 1863; Icon. Gén.
Ophid., Livr. 49, p. 4, fig. 2, 1879.

Philodryas elegans elegans is a ground snake with a conspicuous
dark dorsal band which is continuous anteriorly instead of being
broken into spots and which is bounded by a continuous black line
instead of the row of black spots of elegans rufidorsatus. It has,

318 FIELD MUSEUM OF NATURAL HISTORY—ZOOLOGY, VOL. 24

apparently, a considerably higher number of ventrals and caudals
in both sexes.

This subspecies extends southward in the arid coastal region
from the Rimac Valley to northern Chile. It is known to us from
two specimens in Field Museum, Nos. 34177-34178, collected at
the Cajamarquilla ruins, near Lima, by the senior author, and
from a specimen in the Museum of Comparative Zoology, labeled
only ‘‘Peru.’’ Boulenger’s specimens from Lima and the Island of San
Lorenzo agree excellently with our Cajamarquilla specimens and
with the type in numbers of ventrals and caudals. We are unable
to allocate all of the specimens reported by Boulenger and all of
the cotypes of Dryophylax freminvillei, without re-examination of
the specimens, since many of them have inadequate data as to
locality or sex. There is some indication that a third form with
fewer ventrals and caudals is to be found in southern Peru and adja-
cent Chile (cf. Boulenger’s specimens from Tacna and Chile).

Amaral’s record of this species from Valparaiso, Chile, is doubt-
less in error.

Oxybelis acuminatus Wied

Coluber acuminatus Wied, Isis, p. 667, 1824; Beitr. Naturg. Bras., 1, p. 322,

1825—Espirito Santo River, Brazil.
Dryiophis acuminata Cope, Proc. Amer. Phil. Soc., 17, p. 34, 1877; Boettger,
Ber. Senck. Ges., 1889, p. 314, 1889.

Oxybelis acuminatus Steindachner, Reise Novara, Rept., p. 177, 1867; Dunn,
Proc. Biol. Soc. Wash., 36, p. 186, 1923; Parker, Ann. Mag. Nat. Hist.,
(11), 2, p. 445, 1938.

This extremely elongate snake, often referred to as a typically
arboreal form, appears to extend into arid regions in many parts of
its range. It is one of the few forms in coastal Peru not racially
distinguishable, as far as is known, from specimens in other parts
of its vast range, which extends from northern Mexico to eastern
Brazil and Bolivia.

There are no specimens of this species from coastal Peru in the
collections at our disposal.

Tantilla melanocephala capistrata Cope
Tantilla capistrata Cope, Journ. Acad. Nat. Sci. Phila., (2), 8, p. 181, 1876—
Valley of Jequetepeque, Libertad, Peru.

Tantilla melanocephala (not of Linnaeus) Dunn, Proc. Biol. Soc. Wash., 36,
p. 186, 1923; Parker, Ann. Mag. Nat. Hist., (11), 2, p. 445, 1938.

1943 PERUVIAN SNAKES—SCHMIDT AND WALKER 319

Tantilla melanocephala capistrata is a small terrestrial snake,
brownish above with a black head and nape crossed by yellow bands
on the snout and back of the head and with a yellow spot behind
‘the eye. It is distinguished by contact of the prefrontal and second
supralabial from the Amazonian race or races of melanocephala.

The range of capistrata as here defined appears to include besides
northern coastal Peru the arid valley of the Marafion (Dunn, 1923)
and the Catamayo and Malacatos valleys in southern Ecuador, thus
transgressing the Andes.

Five specimens examined: four from Chiclin, Libertad, presented
by Sr. Constante Larco Hoyle, F.M.N.H. Nos. 33744 and 34285-
34287; and one collected by G. K. Noble at Perico, Cajamarca,
in 1916, M.C.Z. No. 17391.

The Chiclin series includes three males with ventrals respectively
132, 133, and 133, and caudals 56, 30+, and 53; the single female
has ventrals 148 and caudals 46. The Perico specimen, a female,
has ventrals 155 and the tail incomplete. Parker’s female specimen
from the Catamayo Valley has ventrals 158, caudals 49. Thus the
more northern specimens have a considerably higher number of
ventrals; we assume that this gap may be filled by specimens from
Piura. The Chiclin specimens agree in coloration with the type,
which has ventrals 189 and caudals 71, and differs from our speci-
mens in having only a single postocular.

Elapidae

Micrurus mertensi Schmidt

Elaps circinalis Cope, Proc. Amer. Phil. Soc., 17, p. 33, 1877 (not of Duméril

and Bibron).

Micrurus mertensi Schmidt, Field Mus. Nat. Hist., Zool. Ser., 20, p. 192—

Pacasmayo; Parker, Ann. Mag. Nat. Hist., (2), 11, p. 446, 1938.

A coral snake with black rings bordered by yellow rings, the
black rings not in triads; top of head black, the black crown connected
by a single black scale with the nuchal black ring; about 215 ventrals
in males, 233 in females; and caudals respectively about 49 and 35.

Micrurus mertensi appears to be confined to the northern part
of the Peruvian coastal region and the adjacent Catamayo Valley
in Ecuador.

The type and paratypes were examined by the senior author in
the Senckenberg Museum in 1932. His speculation as to a possible
coastal locality, Chanchamayo, to account for a paratype so labeled

320 FIELD MUSEUM OF NATURAL HISTORY—ZOOLOGY, VOL. 24

in the British Museum appears to be unnecessary in view of the
common mislabeling of specimens from dealers; the ‘“Chanchamayo”’
collection in the Dresden Museum, which includes coastal species
like Micrurus tschudii and Oxyrhopus fitzingeri, re-enforces the
suspicion that specimens from Carlos Schunke have repeatedly been
mislabeled, perhaps through the fault of the receiving museum rather
than his.

The relation of the coastal fauna to that of the Marafion Valley
in Cajamarca may indicate that Micrurus peruvianus, from Perico
and Bellavista, is more closely allied to mertensi than was thought
when these two forms were described. Parker (1938, p. 446) has
shown that this species meets Micrurus ecuadorianus and that it
may be directly related; Micrurus peruvianus should also fall into
this series of forms. Additional material is required for an adequate
review of the problem thus raised.

A specimen in the collections of the Academy of Natural Sciences
of Philadelphia, No. 6788, is presumably the specimen recorded by
Cope from Pacasmayo; it is a male with ventrals 212 and caudals 42,
and has black rings 18 + 6, thus differing slightly from the range of
variation in the Senckenberg Museum specimens.

Micrurus tschudii tschudii Jan

Elaps tschudii Jan, Rev. Mag. Zool., 1858, p. 524, 1858—Peru (restricted to
Rimac Valley, Department of Lima); Cope, Proc. Amer. Phil. Soc., 17,
p. 83, 1877; Boettger, Ber. Senck. Ges., 1889, p. 316, 1889; Boulenger,
Cat. Snakes Brit. Mus., 3, p. 422, 1896; Werner, Abh. Mus. Dresden, 9,
No. 2, p. 10, 1901.

Micrurus tschudii Schmidt and Schmidt, Field Mus. Nat. Hist., Zool. Ser.,
12, p. 182, pl. 12, 1925.

Micrurus tschudii tschudii Schmidt, Field Mus. Nat. Hist., Zool. Ser., 20,
p. 202, 1936.

A coral snake readily distinguished from any other snake in the
Peruvian coastal region by the arrangement of its black rings in
triads, enclosing the pairs of yellow rings within the outer black
rings and the triads separated by relatively narrow red rings. Dis-
tinguished from the subspecies olssoni by black spotting of the
lower labials and anterior chin shields and of the yellow rings, by
the tendency for the first black ring (the nuchal ring) to be complete
beneath, and by a lower number of ventrals.

The typical subspecies ranges from the Department of Libertad
to the Rimac Valley. See discussion of the variation cline under
Micrurus tschudii olssoni, below.

1943 PERUVIAN SNAKES—SCHMIDT AND WALKER 321

Micrurus tschudii olssoni Schmidt and Schmidt
Micrurus olssoni Schmidt and Schmidt, Field Mus. Nat. Hist., Zool. Ser., 12,
p. 180, pl. 11, 1925—Negritos, Piura, Peru.
Micrurus tschudii olssoni Schmidt, Field Mus. Nat. Hist., Zool. Ser., 20, p.
202, 1936.
Micrurus tschudit Amaral, Proc. U. S. Nat. Mus., 67, Art. 24, p. 17, 1925;
Parker, Ann. Mag. Nat. Hist., (11), 2, p. 445, 1938.
Distinguished from Micrurus tschudii tschudii, in addition to
the characters mentioned above, by considerably larger size.

Confined to the northern part of the Peruvian coastal region,
in Piura, perhaps meeting M. t. tschudii in Libertad, and ranging
from Piura into southern Ecuador, where, as Parker (1938, p. 445)
points out, an additional form may perhaps be distinguished.

Considerable series of Micrurus tschudii are now available, and
examination of these specimens shows that there is a well-marked
cline in the number of ventrals from low at the north, in the Cata-
mayo Valley in Ecuador, to high in the Rimac Valley. This is
shown below.

Region pce cl Sex Ventrals —
Catamayo Valley.......... { ; o ronan 18-14
Pirate ce ean { 4 score ter
Libertad and Ancash....... { a 2 tie 12-19
RANMA han ged sh ad or es { : . er fone
SADOVIR Caan eco ee { : e A io GR ee

The regularity of the above tabulation is marred by a male
specimen in the Museum of Comparative Zoology from the desert
between Trujillo and Chicama (No. 43751) with ventrals only 188,
and a similarly aberrant male from Chiclin with only 193. It
is by no means impossible that the Chiclin specimen might have
been collected at a more northern locality, as the collection received
from the Hacienda Chiclin had accumulated over a considerable
period of years.

A further difficulty arises in allocating specimens without specific
locality or with the supposedly erroneous locality Chanchamayo; we
have assigned these as best we could to the Department of Lima.

322 FIELD MUSEUM OF NATURAL HISTORY—ZOOLOGY, VOL. 24

Four specimens in the Museum d’Histoire Naturelle in Paris,
collected by M. Wiener, are entered as from ‘“‘Bolivia.”” We believe
this to be in error. These specimens have a low number of ventrals,
agreeing with the Piura series, but have a higher number of triads
than is to be found in the forty-five other specimens.

On the whole, the most conspicuous step in the cline of ventrals
is between the Chiclin and Pacasmayo specimens and the series
from Piura. Thus the break between the northern and southern
forms does not correspond with that in Oxyrhopus fitzingeri or
Philodryas elegans. It may well be that the supposed “step’’ is
illusory and that a larger and more widely distributed series will
exhibit a more uniform cline.

Crotalidae

Trimeresurus barnetti Parker

Bothrops barnetti Parker, Ann. Mag. Nat. Hist., (11), 2, p. 447, 1938—mouths
of the Quebradas Honda and Perines between Lobitos and Talara, Piura,
Peru; paratypes from Lobitos.
T. barnettt is a small desert pit-viper closely resembling the
fer-der-lance (7. atrox) but differing in its smaller size, lower number
of subeaudals, and the enlarged terminal scute of the tail.

This species is known only from the low coastal desert of northern
Piura, between Lobitos and Negritos.

The material examined consists of a single female specimen,
F.M.N.H. No. 11018, collected at Quebrada Parinas near Negritos
by A. A. Olsson, May, 1928. This has ventrals 184, caudals 48, and
agrees essentially with the type series; a row of small lateral spots
present in our specimen is not mentioned by Parker.

Trimeresurus pictus Tschudi

Lachesis picta Tschudi, Fauna Peruana, Herp., p. 61, pl. 10, 1845—higher
montafia of Peru (in error); Boulenger, Cat. Snakes Brit. Mus., 3, p. 540,
1896—Lima, Peru.

Bothrops pictus Jan, Elenco Sist. Ophid., p. 126; Icon. Gén. Ophid., Livr.
47, pl. 3, fig. 3, pl. 4, fig. 2, 1875; Amaral, Proc. U. S. Nat. Mus., 67,
Art. 24, p. 29, 19265.

Trimeresurus pictus is a medium-sized pit-viper characterized
by a lower number of scale rows at mid-body than barnetti, 21-23
as opposed to 23-25, a series of irregular mid-dorsal blotches, two
rows of alternating lateral spots, and a head pattern of obliquely
transverse markings.

1943 PERUVIAN SNAKES—SCHMIDT AND WALKER 323

This is the common pit-viper of the coastal desert region, ranging
from Libertad south to Arequipa. It is said to occur at Chiclin, and
is here reported from Chimbote, Chosica, and the Majes Valley.

We have examined six specimens, F.M.N.H. Nos. 5662-5664, from
Chimbote, Ancash, collected by M. P. Anderson in 1912; No. 39991,
from the Majes Valley, collected by Sr. Romano; M.C.Z. No. 3578,
taken at Lima by Samuel Garman; and M.C.Z. No. 45716, from
Chosica, collected by David and Bruce Hertig and G. P. Gardner
in 1940.

In the three male specimens the ventrals number 167-169 and
caudals 46-49; in three females 170-173 and 44-48. We assume
the number of caudals given by Tschudi, 74, to be a misprint for
47. Our series agrees well with Boulenger’s re-description of the
species, but exhibits considerable variation in the head shields.
Scale rows between eye and upper labials one or two; upper labials
8 to 12, the second usually entering the pit, occasionally the third
(one side on M.C.Z. No. 45716), or none (F.M.N.H. No. 39991).
The general coloration may be pale brown or light gray. With the
few specimens available, we are not able to divide the series into a
northern and a southern race, as we had thought might be possible
(Schmidt and Walker, 1948, p. 295).

REFERENCES

AMARAL, AFRANIO DO

1925. South American Snakes in the Collection of the United States National
Museum. Bull. U. S. Nat. Mus., 67, Art. 24, pp. 1-30.

1930. Revisio do genero Drymarchon Fitzinger, 1843. Mem. Inst. Butantan,
4, pp. 321-330, figs. 1-3.

BOETTGER, OSKAR

1889. Herpetologische Miscellen. XI. Nordwest-Peru. Ber. Senck. Ges., 1889,
pp. 308-316.

BOULENGER, G. A.
1893. Catalogue of Snakes in the British Museum (Natural History). 1, xiii
+448 pp., figs. 1-26, pls. 1-28.
1894. Idem. 2, xi+382 pp., figs. 1-24, pls. 1-20.
1896. Idem. 3, xiv+727 pp., figs. 1-37, pls. 1-25.

Copg, E. D.

1876. Report on the Reptiles Brought by Professor James Orton from the
Middle and Upper Amazon, and Western Peru. Journ. Acad. Nat. Sci.
Phila., (2), 8, pp. 159-183.

1877. Synopsis of the Cold-blooded Vertebrata Procured by Prof. James
Orton during His Exploration of Peru in 1876-77. Proc. Amer. Phil. Soc.,
17, pp. 33-49.

324 FIELD MUSEUM OF NATURAL HISTORY—ZOOLOGY, VOL. 24

Dunn, E. R.
sini a Snakes from Northwestern Peru. Proc. Biol. Soc. Wash., 36, pp.

1936. Notes on North American Leptodeira. Proc. Nat. Acad. Sci., 22, pp.
689-698.

HERTIG, MARSHALL
1942. Phlebotomus and Carri6n’s disease. Suppl. Amer. Journ. Trop. Med.,
22, No. 5, pp. 1-81, 9 pls.

PARKER, H. W.

1938. Vertical Distribution of Some Reptiles and Amphibians in Southern
Ecuador. Ann. Mag. Nat. Hist., (11), 2, pp. 488-450.

PERACCA, M. G.

1904. Viaggio del Dr. Enrico Festa nell’Ecuador e regioni vicine. Rettili ed
Anfibii. Bol. Mus. Zool. Torino, 19, No. 465, pp. 1-41.

SCHMIDT, K. P.
1936. Preliminary Account of Coral Snakes of South America. Field Mus.
Nat. Hist., Zool. Ser., 20, pp. 189-203.

—— and ScHMIpT, F. J. W.

1925. New Coral Snakes from Peru. Field Mus. Nat. Hist., Zool. Ser., 12, pp.
127-134, pls. 11-12.

—— and WALKER, W. F., IR.
1943. Peruvian Snakes from the University of Arequipa. Field Mus. Nat.
Hist., Zool. Ser., 24,.pp. 279-296.

SMITH, H. M.

1941. A Review of the Subspecies of the Indigo Snake (Drymarchon corais).
Journ. Wash. Acad. Sci., 31, pp. 466-481, 2 figs.

Stuart, L. C.

1941. Studies of Neotropical Colubrinae VIII. A revision of the genus Dry-
odeokts. oh Mise. Publ. Mus. Zool. Univ. Mich., 49, pp. 1-106, figs.
—13, pls. ,

TSCHUDI, J. J. VON
1845. Untersuchungen iiber die Fauna Peruana. Herpetologie. St. Gallen.
pp. 1-80, pls. 1-12.

WEBERBAUER, AUGUST
1922. Die Vegetationskarte der peruanischen Anden zwischen 5° und 17° S.
Petermann’s Geogr. Mitt., 68, pp. 89-91, 120-122, pl. 13.

1936. Phytogeography of the Peruvian Andes, in MACBRIDE, J. F., Flora of
Peru. Field Mus. Nat. Hist., Bot. Ser., 13, pt. 1, pp. 13-87, map.
WERNER, FRANZ

1901. Reptilien und Batrachier aus Peru und Bolivien. Abh. Ber. Mus.
Dresden, 9, No. 2, pp. 1-14, 1 fig.

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