Variation, Distribution, and Taxonomic Status of
the Xantusiid Lizard Lepidop/zyma tarascae
UBALDO Gu z.\IA"'· VILLA
OSCAR nORES· \1LLELA
WALTER SCIIMIDT·BALLARDO
MlUeo d~ Zoo/agia. Foclliuui de CienciaJ
Unil'ersidiui AUlanomo NacioM! de Mhico
A.P. 70·399, Mizico D.F. 04SJO. Minco
DNi
ROBERT L BEZY
Amphibiaru and Rtptiles. Natural Hislory' Mu.uum of Los AngcIts Count)'
Los Angtles. Coli/ornia 90007. US.-4.
Lepidophyma torascoe was described by Bezy et al. (1982) on
the basis of three specimens from "near Mexiquillo. Aquila Dis·
trict. Michoacan, Mexico." This locality is on the coast of
Michoad.n. ca. 16 km (by Hwy 200) Vi'NW Caleta de Cam pos at
18°08'N, J02 ' 56'W, but was listed inadvenentl y as 18°08'N,
103°56'W in the original description. Our observations indica te
that the vegeution near Mexiquillo consists of degraded "Bosque
Tropical Caducifolio" (Rzedowski 1978 ). whereas Alvarez and
Diaz· Pardo (1983:143) list the type specimens as having been
collected in "encinar," Moreover. field work conducted bv the
authors in the vicinity of Mexiquillo has failed to produce addi.
tional specimens of the species. A speci3.1 effon was made to se:lrC h
rocky habitats similar to that mentioned in the original descrip·
tion. As members of the 2enus can be ex[[aordinarilv difficult to
collect, additional work-is necessary ' to establi sh 'definiti\'ely
whether L. roroscoe actually occurs at Mexiquillo. or wh ether
the designated type locality may have been in error.
Recent field work. however. has established the presence of
Lepidophyma torascoe in the nonhern sector of the Sierra de
Coalcoman. A specimen (MZFC 8603) was collected in a cave
(Cueva de la Virgen) on the canyon of the Ri o Chilitos (18' 52 ':-;
and 102°50W) in the m unicipality ofAguililia. Michoacan. Ths
is ca. 65 krn N of the designated type locality and places the spe·
cies near the Balsas Basin. The Coalcoman locality lies at 1225
m ele\'3tion in a transition zone between tropical de cid uous forest and oak woodland, conforming close r with the vegetation reo
poned by Alvarez and Diaz·Pardo ('1 983: 143) for the type series.
The specimen from the Sierra de Coalcoman differs somewhat
in morphology from the type series of Lepidoph\'ma /Oroscoe. It
has slightly fewer total fe moral pores (14 v's. 16-1 8) and gulars
(40 vs. 41 -43) and more dorsal scales ( 159 vs. 145-150). lt shares
with the type series the presence (on each side of the neck) of an
uninterrupted longitudinal row of enlarged tubercles extending
from the posteroventral margin of the tympan um to above the
gular fold (Fig. 3 in Bezy et al. 1982). a feature th at was uti lized
by Bezy and Camarillo (1995) to identify L. /Oroscoe in their key
10 the xantusiids of Mexico. However. in the Coal coman speci ·
men this post·tympartic row of tubercles is nOt as di stinct, i.e .. it
is less clearly separated from the scattered enlarged tubercles of
the upper nuchal area than it is in the type series. approaching the
condition obse rved in some L. smiIhii fro m Chiapas (e.g .. MVZ
19 1448-49). The Coalcoman specimen lacks an other di stinctive
feature foun d in the type series of L. lorascae. It has three dorsal
interwhorls separating the enlarged caudal whorls throughout the
length of the tail. whereas in the type series there are twO in most
of the proximal caudal segments (but three distall y).
As is often the case with LepidophynUl. species deci sions must
78
co~te~d with limited sample sizes. discordant morphological
vanaDon, and geographically disjunct populations (Bezy 1984).
Although the Coalcoman specimen differs somewhat from the
o,ther,three known specimens of L. Tarascae we provisionally as.
"gn II to that species. The four specimens thu s assigned to L.
to roscoe have fe wer total femoral pores (14-18) than al l other
members of the genus except L. dOn/omasi, L. occulor. and L.
smithii. From these L. Ioroscoe differs most markedly from L.
donromosi in having strongl y enlarged lateral tubercle rows. In
some morphological features the Coal coman specimen bridges
the morphological gap between L. to roscoe and L. smithii. How·
ever, we retain L. 1arascae as a separate species as all four known
specimens differ from L. smithii (302 specimens examined) and
L. occulor (lJ exami ned ) in having fewer than ] 62 dorsal scales
and fewer than 44 gu lars.
Ackrw\dedgnunrs.- \Ve thank H. W. Greene (MVZ) for making specimens a\'ailable for siudy. Francisco Vargas Santa Maria for assistance
with the field work. and Kathryn Bolles. Lee Fitzgerald. and an anony~
mous re viewe r for critica1 review of a previous version of the manu·
script. OFV was supponed by a Grant of Direcci6n General de Asun los
del PeI!>onaJ AC::ldemico. DGAPA. U ~AM (L"'':!03493) and l'\,alionaJ
Science Foundauon gram DEB91·1909 J.
ALVAREZ. T. . .-\="o E. DJ.-\Z,P"ROO. 1983. Estudio de una col ecci6n
herpelofaunislica de la costa de ~1ich oacan. Mexico. An. Esc. !'\ac.
Cien.:. BioI.. ~1ex . ~ 7; 129-14 7.
BEZY . R. L. J9 8~. Systematics of xantusiid lizard s of the genus
upidophyma in nonheaslem Mexico. Contrib. Sci . 3~9: 1-16.
_ _ _ , A~D J. L c'-\M .-\RllLO R. 1995. Key to the species of the
Xantusiidae in Mexico. In O. Flores v.. F. Mendoza Q .. an d G.
GonuJez P. reds.). RecopiJaci 6n de Cla\'es para la Detenninaci6n de
Anfibios y Reptiles de Mexico. pp. 186-188. Pub!. Esp. Mus. Zoo!.
U~A.\lIO :I -~ 85.
___ . R. G. WEBB. A!\"D T. ALVAREZ. 1982. A new species of the genus
upidophyma (Sauna: XaOlusiidae ) from Michoadn. Mexico. Herpe loiogica 38:36 1-366.
RzEoov.st.;J. J. 19i5. Ve£etaci6n de Mex ico. Ed. Limosa. Mexico. ~ 3 ~
pp.
Hyla cm t'~a fGreen Treefr01!-). llIusltation by Michael G. Frick.
HerpelOlogicol Redew 29(2). 1998