Produced by Chris Curnow, Joseph Cooper, Josephine Paolucci
and the Online Distributed Proofreading Team at
https://www.pgdp.net.
UNIVERSITY OF KANSAS PUBLICATIONS
MUSEUM OF NATURAL HISTORY
Volume 15, No. 1, pp. 1-148, pls. 1-6, 11 figs.
December 20, 1961
[Transcriber's Note: Words surrounded by cedillas, like ~this~ signifies
words in bold. Words surrounded by underscores, like _this_, signifies
words in italics.]
The Amphibians and Reptiles of Michoacan, Mexico
BY
WILLIAM E. DUELLMAN
UNIVERSITY OF KANSAS
LAWRENCE
1961
UNIVERSITY OF KANSAS PUBLICATIONS, MUSEUM OF NATURAL HISTORY
Editors: E. Raymond Hall, Chairman, Henry S. Fitch,
Theodore H. Eaton, Jr.
Volume 15, No. 1, pp. 1-148, pls. 1-6, 11 figs.
Published December 20, 1961
UNIVERSITY OF KANSAS
Lawrence, Kansas
PRINTED IN
THE STATE PRINTING PLANT
TOPEKA, KANSAS
1961
The Amphibians and Reptiles of Michoacan, Mexico
BY
WILLIAM E. DUELLMAN
CONTENTS
PAGE
INTRODUCTION 3
Acknowledgments 5
Historical Account 7
NATURAL LANDSCAPE 9
GEOGRAPHY OF THE HERPETOFAUNA 13
ANNOTATED LIST OF SPECIES 13
Amphibia 14
Caudata 14
Salientia 20
Reptilia 56
Testudines 56
Crocodilia 58
Sauria 59
Serpentes 88
SPECIES OF QUESTIONABLE OCCURRENCE 124
GAZETTEER 129
SUMMARY 141
LITERATURE CITED 142
INTRODUCTION
For almost 30 years North American herpetologists have been making
extensive collections of reptiles and amphibians in Mexico. Some parts
of the country, because of their accessibility, soon became relatively
well known; other regions lying off the beaten path were bypassed or
inadequately sampled. Principally in the last decade herpetologists have
been entering regions from which no collections previously were
available in an attempt to fill gaps in known distributions and to
discover unknown species of animals. In 1950 Dr. Donald D. Brand led an
exploration party from the University of Texas to the poorly explored
and faunistically unknown region of southwestern Michoacan. James A.
Peters accompanied Brand and collected amphibians and reptiles. In 1951
I welcomed the opportunity to accompany Brand on a second expedition to
southwestern Michoacan. Such was the beginning of my interest in the
herpetofauna of the region. I have been fortunate to return to Michoacan
on four successive trips, all of which had as their purpose the
accumulation of data on the herpetofauna that would result in a survey
of the component species and an analysis of their distribution.
My original intention was to amplify Peters' (1954) study based on the
collections made by him in 1950 and by me in 1951 in the Sierra de
Coalcoman. But it soon became evident that in order to understand the
relationships of the herpetofauna of the Sierra de Coalcoman, the
species inhabiting the Tepalcatepec Valley and adjacent mountain ranges
would have to be studied. In the course of making that study I examined
all specimens from Michoacan already in museums.
There have been few detailed herpetofaunal studies in Mexico. The first
such study of any consequence was that by Bogert and Oliver (1945) on
the herpetofauna of Sonora. In that paper the authors analyzed the fauna
from a geographic view and showed the transition from tropical species
in the southern part of the state to members of the Sonoran Desert
assemblage to the north. Martin (1958) made a detailed study of the
herpetofauna of the Gomez Farias region in southern Tamaulipas; he
emphasized the ecological distribution of amphibians and reptiles in
that region with special reference to cloud forests. Duellman (1958c)
presented a preliminary geographic analysis of the herpetofauna of
Colima with special reference to the continuity of the species
inhabiting the lowlands. Zweifel (1960) discussed in detail the
herpetofauna of the Tres Marias Islands and commented on the derivation
of the fauna. Duellman (1960d) provided a detailed account of the
geographic distribution of the amphibians known to occur in the lowlands
of the Isthmus of Tehuantepec and attempted to account for the present
patterns of distribution.
The present report is the first of two parts dealing with the
herpetofauna of Michoacan. The purpose of this part is to present a full
account of the species of amphibians and reptiles known to inhabit the
state of Michoacan; the accounts of the species are accompanied by a
brief description of the natural landscape and of the various
assemblages of species comprising the major faunistic groups within the
region. A gazetteer of collecting localities is appended. The second
part of the study, now in preparation, deals with the ecological and
historical geography of the herpetofauna. Since the present part will be
of interest primarily to systematic herpetologists, I have decided to
separate it from the more general material of interest to
biogeographers.
One of the major problems that faces the worker undertaking a faunal
study is the presence of species or genera of unsettled systematic
status. My work in Michoacan has been no exception; fifteen separate
studies were undertaken in an attempt to solve systematic problems in
certain groups. Some systematic problems still remain but are of little
consequence insofar as the entire faunal picture is concerned, or are so
involved as to be impractical to undertake at this time. In accounts of
species, such problems are mentioned in the hope that they will interest
some worker who will be inclined to investigate them.
ACKNOWLEDGMENTS
While engaged in the study of the herpetofauna of Michoacan I have built
up a debt of gratitude to many individuals, without whose aid my
ambition to complete my study never would have been realized. I am
especially grateful to those individuals who accompanied me in the
field; Lee D. Beatty, Richard E. Etheridge, Carter R. Gilbert, Fred G.
Thompson, Jerome Tulecke, and John Wellman offered stimulating
companionship and valuable assistance. On many occasions they suffered
hardships on behalf of my interests.
Studies of my own specimens have been augmented by material from other
institutions. For permitting me to examine specimens in their care I am
indebted to W. Frank Blair, Charles M. Bogert, Doris M. Cochran, William
B. Davis, James R. Dixon, the late Emmett R. Dunn, Josef Eiselt, Alice
G. C. Grandison, Norman Hartweg, Robert F. Inger, Arthur Loveridge, the
late Karl P. Schmidt, Hobart M. Smith, Robert C. Stebbins, Margaret
Storey, Edward H. Taylor, and Richard G. Zweifel.
Several people have aided me in the study of specimens and in the
analysis of data; I am grateful to Donald D. Brand, who first introduced
me to Michoacan; since that time I have benefited much from his
knowledge of the area. James A. Peters provided me with essential
information concerning his field work in southern Michoacan in 1950.
James R. Dixon and Floyd L. Downs have permitted me to use freely the
material and data that they accumulated in their recent field work in
Michoacan. Norman E. Hartweg allowed me to use the specimens and data
that he gathered in his survey of the herpetofauna in the region of
Volcan Paricutin. L. C. Stuart, Charles F. Walker, and Richard G.
Zweifel have helped in unraveling some of the systematic and
distributional problems.
I am especially grateful to my wife, Ann, who for six months helped me
track down elusive species and explore new areas. Furthermore, she has
stimulated me to carry this study to completion.
Many people in Michoacan favored the field parties with quarters,
transportation, and valuable information, which greatly facilitated the
field work. In this respect I am especially indebted to Ingeniero Ruben
Erbina of Ingenieros Civiles Asociados, who not only let us use his home
as our headquarters, but through a letter of introduction gave us the
"key" to southern Michoacan. Ingeniero Pedro Tonda aided us in Arteaga
and San Salvador. Ingeniero Anastacio Perez Alfaro of the Comision
Tepalcatepec in Uruapan provided the latest maps of southern Michoacan
and much essential information pertaining to travel conditions in the
area. Senor Nefty Mendoza gave us a home in Dos Aguas; this kindness
allowed us to work in this interesting region during the height of the
rainy season. Mr. and Mrs. Bob Thomas let us make use of their
facilities at Hacienda Zirimicuaro. The naval officers at the Estacion
Marina at Playa Azul made pleasant what might have been a dreadful stay
in that small coastal village. To the managers and pilots of Lineas
Aereas Picho in Uruapan I owe special thanks for going out of their way
on more than one occasion to transport a stranded snake-hunter.
Throughout the months of field work beginning in 1955 I constantly have
been aided by the authorities and workers of the Comision Tepalcatepec,
a subdivision of the Secretaria de Caminos y Obras Publicas, and of the
private corporation, Ingenieros Civiles Asociados. Much of the field
work in Michoacan was made possible only through the co-operation of the
natives who supplied mules, acted as guides, and aided in the collection
of specimens. I have learned a great deal from these people. They will
never see this report. Their work as guides, muleteers, and collectors
greatly assisted me with the mountains of equipment that had to be piled
on the backs of scrawny mules for transportation to places where the
natives seldom trod. Their efforts in behalf of Don Guillermo never will
be forgotten; I extend an especially hearty _muchas gracias_ to
Benjamin, Ignacio, Jesus, Lorenzo, Mariano, and Remigio.
Much of the work on this report was done while I was associated with the
Museum of Zoology at the University of Michigan. I thank Norman E.
Hartweg and T. H. Hubbell for making available to me the facilities of
the museum and for their numerous courtesies that aided me so much.
My field work in Michoacan was supported by the Museum of Zoology at the
University of Michigan (1951), by the Horace H. Rackham School of
Graduate Studies of the University of Michigan (1955), by the Penrose
Fund of the American Philosophical Society (1956), by the Bache Fund of
the National Academy of Sciences (1958), and by the University of Kansas
Endowment Association (1960).
Permits for collecting specimens in Mexico were provided by the
Direccion General de Caza through the courtesy of Ing. Juan Lozano
Franco and Luis Macias Arellano.
Historical Account
Unlike many parts of southern Mexico and northern Central America,
Michoacan received no attention from the collecting expeditions of the
European museums in the last century. The earliest known herpetological
specimens from Michoacan were obtained by Louis John Xantus, who was
appointed U. S. Consul to Colima in 1859. In April, 1863, Xantus
collected at Volcan Jorullo in Michoacan; in April and May of the same
year he collected along the coast of Michoacan between the Rio Cachan
and the Rio Nexpa. His small collection of 19 extant specimens is in the
United States National Museum. Alfredo Duges, a resident of Guanajuato,
Mexico, made early contributions to the knowledge of the herpetofauna of
Michoacan. In 1885 he described _Sonora michoacanensis_, and in 1891 he
described _Eumeces altamirani_; from what is known of the distribution
of these species, he probably had collected in the Tepalcatepec Valley.
During their biological survey of Mexico, Edward W. Nelson and Edward A.
Goldman spent a limited amount of time in Michoacan in 1892 and again in
1903 and 1904. Most of their collecting was done on the plateau in the
north-central part of the state; their collections are in the United
States National Museum. While collecting fishes in southern Mexico, Seth
E. Meek obtained some amphibians and reptiles from Lago de Patzcuaro in
1904; these are in the collections of the Chicago Natural History
Museum. In 1908 Hans Gadow ventured into the then unexplored "tierra
caliente" of the Balsas Valley and collected at Volcan Jorullo and other
localities in the valley. Later in the same year he collected at
Guayabo, San Salvador, and Arteaga in the Sierra de Coalcoman and at
Buena Vista and Cofradia in the Tepalcatepec Valley. His collections
were deposited in the British Museum (Natural History) and the
Naturhistorisches Museum Wien.
The first thirty years of the present century saw little more field work
in Michoacan. In the 1930's Edward H. Taylor and Hobart M. Smith
collected throughout much of Mexico. At various times they worked in
Michoacan, principally along the road from Mexico City to Guadalajara.
In 1935 Hobart M. Smith spent a week at Hacienda El Sabino south of
Uruapan; he revisited the locality again in 1936 and made a large and
important collection of amphibians and reptiles from the upper limits of
the arid tropical scrub forest in the Tepalcatepec Valley. Specimens
collected by Smith and Taylor were incorporated into the Edward H.
Taylor-Hobart M. Smith collection, which subsequently was deposited in
part in the Museum of Natural History at the University of Illinois and
in part in the Chicago Natural History Museum. In 1939 Hobart M. Smith
collected at Patzcuaro and between Uruapan and Apatzingan; these
collections, made while he was a Walter Rathbone Bacon Scholar of the
Smithsonian Institution, are deposited in the United States National
Museum. In 1940 and 1941 Frederick A. Shannon, who was a member of the
Hoogstraal Expeditions under the auspices of the Chicago Natural History
Museum, collected on Cerro de Tancitaro and at Apatzingan; an account of
the specimens collected there was published by Schmidt and Shannon
(1947).
The eruption of Volcan Paricutin in February, 1943, attracted the
attention of many biologists, a group of which from the Museum of
Zoology at the University of Michigan collected in the Cordillera
Volcanica in 1945 and 1947. The amphibians and reptiles were collected
and studied by Norman E. Hartweg. In 1950 James A. Peters accompanied
Donald D. Brand on a preliminary exploration of the western part of the
Sierra de Coalcoman and adjacent Pacific coast of Michoacan; in the same
year Peters collected also on the Mexican Plateau and at Volcan Jorullo.
His specimens are in the Museum of Zoology at the University of
Michigan. Since 1950 many biologists have collected in Michoacan in the
course of work on certain groups of animals or in general surveys. In
this way Raymond Alcorn, Robert W. Dickerman, James R. Dixon, Floyd L.
Downs, Emmet T. Hooper, and Robert R. Miller have contributed to our
knowledge of the herpetofauna.
As stated previously, my own field work in Michoacan began in 1951, when
I accompanied Donald D. Brand on an exploring expedition to the
southern part of the state. In that year a short time was spent on the
Mexican Plateau, principally in the area around Lago de Cuitzeo, and at
Volcan Jorullo. In July and August we made our headquarters at
Coalcoman. From that town the field party travelled southward to Maruata
on the Pacific coast and thence back over the mountains to Coalcoman.
Later in that summer we travelled by mule from Coalcoman southeastward
to the mouth of the Rio Nexpa. In 1955, accompanied by Lee D. Beatty,
Carter R. Gilbert, and Fred G. Thompson, I collected in the Tepalcatepec
Valley and at Coalcoman. We made a mule trip from Coalcoman to Cerro de
Barolosa, where we made the first collections from the pine-fir forests
in the Sierra de Coalcoman. Later in the same summer Carter R. Gilbert
and I spent a week at Playa Azul on the Pacific coast. In March, April,
and May, 1956, my wife and I collected for a short time in the
Cordillera Volcanica and on the Mexican Plateau. In early April we moved
into the Tepalcatepec Valley, where we collected intensively between
Churumuco and Tepalcatepec. In May we collected on the Pacific coast
between Boca de Apiza and La Placita. In July and August, 1956,
accompanied by Richard E. Etheridge, we returned to Michoacan and again
collected on the Mexican Plateau and in the Cordillera Volcanica, before
moving into the Tepalcatepec Valley. In an attempt to fill in gaps in
the known distributions of many species and to sample the fauna in some
previously uncollected areas, I returned to Michoacan in June, 1958.
Accompanied by Jerome B. Tulecke and John Wellman, I collected on the
Mexican Plateau in the northwestern part of the state, on the southern
slopes of the Cordillera Volcanica, and in the Tepalcatepec Valley. Most
of our time was spent in the Sierra de Coalcoman, where we collected at
Aguililla, Artega, and Dos Aguas. In 1960 two days were spent in
Michoacan; a small collection was made in the eastern part of the
Cordillera Volcanica. With the exception of the specimens collected in
1960, which are at the Museum of Natural History at the University of
Kansas, the specimens that I have collected in Michoacan are in the
Museum of Zoology at the University of Michigan.
NATURAL LANDSCAPE
A proper understanding of the geographical distribution of animals in a
given region is possible only after a thorough acquaintance with the
geography of the region. Likewise, in order to gain a knowledge of the
ecological distribution and relationships of the components of the
fauna, it is necessary to study the animals in their natural
environments. In order to give the reader a picture of the physical
features and the major animal habitats within the state of Michoacan,
the following brief description is offered. Each of these facets
mentioned below will be elaborated in detail in my final report on the
herpetofauna of Michoacan.
Physiography
The state of Michoacan comprises an area of 60,093 square kilometers
(Vivo, 1953). Within this area the rugged terrain has a total relief of
nearly 4000 meters. There have been several attempts to classify the
physiographic provinces of Mexico; the classification used here is a
slight modification of the scheme proposed by Tamayo (1949). I have
tried to keep the system as simple as possible, but still useful in
discussing the distribution of animals living in the region. For general
purposes the state of Michoacan can be divided into lowlands and
highlands as follows:
LOWLANDS
Pacific Coastal Plain
Balsas-Tepalcatepec Basin
HIGHLANDS
Mexican Plateau
Cordillera Volcanica
Sierra de Coalcoman
Although the lowlands in the state are continuous, they are only
narrowly connected and thus form two distinct physiographic and biotic
areas. The Pacific Coastal Plain in Michoacan extends for a distance of
about 200 kilometers (airline) from the Rio Coahuayana to the Rio
Balsas. The coastal plain is broad between the Rio Coahuayana and San
Juan de Lima, and between Las Penas and the Rio Balsas, where the hills
rise some 12 kilometers inland from the sea. Between San Juan de Lima
and Las Penas the mountains extend to the sea; in this region rocky
promontories form precipitous cliffs dropping into the sea. Between the
promontories are small sandy or rocky beaches.
Lying to the north of the Sierra de Coalcoman and the Sierra del Sur,
but south of the Cordillera Volcanica, is a broad structural depression,
the Balsas-Tepalcatepec Basin. The western part of this basin, which
separates the Sierra de Coalcoman from the Cordillera Volcanica, is the
valley of the Rio Tepalcatepec, a major tributary of the Rio Balsas. The
eastern part of the basin is the valley of the Rio Balsas. From the
point of junction of the two rivers, the Rio Balsas flows southward
through a narrow gorge, which separates the Sierra de Coalcoman from
the Sierra del Sur, to the Pacific Ocean. In Michoacan the floor of the
Balsas-Tepalcatepec Basin varies from 200 to 700 meters above sea level.
The central part of Mexico is a vast table-land, the Mexican Plateau,
the southern part of which extends into northern Michoacan. In this
region the terrain is rolling and varies from 1500 to 1900 meters above
sea level. Many small mountain ranges rise from the plateau and break
the continuity of the rolling table-land. Located on the southern part
of the Mexican Plateau in Michoacan are several lakes, the largest of
which are Lago de Chapala, Lago de Cuitzeo, and Lago de Patzcuaro.
Bordering the southern edge of the Mexican Plateau is a nearly unbroken
chain of volcanos, the Cordillera Volcanica. The highest peaks in
Michoacan, Cerro San Andres (3930 meters) and Cerro de Tancitaro (3870
meters), are in this range. Parts of the Cordillera Volcanica in
Michoacan are known by separate names; these are, from west to east:
Sierra de los Tarascos, Sierra de Ozumatlan, and Serrania de Ucareo.
Lying between the Tepalcatepec Valley and the Pacific Ocean, and east of
the Rio Coahuayana and west of the Rio Balsas, is an isolated highland
mass, the Sierra de Coalcoman. This mountain range rises to elevations
of slightly more than 3000 meters. It has a length of about 200
kilometers and a width of about 80 kilometers. Except for a relatively
low connection with the Cordillera Volcanica, the Sierra de Coalcoman is
isolated from other mountain ranges in southwestern Mexico.
CLIMATE
The climates in Michoacan vary from tropical in the lowlands to cool
temperate at high elevations in the Sierra de Coalcoman and Cordillera
Volcanica. The highest temperatures are known in the Balsas-Tepalcatepec
Basin, where at Churumuco the mean annual temperature is 29.3 deg. C. and
the range of monthly means is 3.5 deg. C. (Contreras, 1942). Frosts occur
sporadically on the Mexican Plateau, and in the winter snow falls on the
highest mountains.
Precipitation varies geographically and seasonally. Most of the rain
falls between June and October. In the Balsas-Tepalcatepec Basin
rainfall in the rest of the year is negligible. The annual average
rainfall at Coahuayana on the Pacific Coastal Plain is 871 mm.
(Guzman-Rivas, 1957:52). In the Balsas-Tepalcatepec Basin rainfall
seldom exceeds 800 mm. per year. In the mountains precipitation is
heavier and somewhat more evenly distributed throughout the year, but
still definitely cyclic. For example, Uruapan (elevation, 1500 meters)
receives an average annual rainfall of 1674 mm. (Contreras, 1942). The
prevailing winds are from the Pacific Ocean. The southern (windward)
slopes of the Sierra de Coalcoman probably receive more rain than any
other part of the state. The Balsas-Tepalcatepec Basin lies in a rain
shadow of the Sierra de Coalcoman, and the Mexican Plateau lies in a
somewhat less drastic rain shadow of the Cordillera Volcanica; these are
the driest regions in the state.
VEGETATION AND ANIMAL HABITATS
For the purposes of this report I have adopted the classification of
types of vegetation that seem to me most significant in terms of
ecological distribution of reptiles and amphibians in Michoacan. These
types are as follows:
TEMPERATE (1000-4000 meters)
Fir Forest (2400-4000 meters)
Pine-oak Forest (1000-4000 meters)
Mesquite-grassland (1500-2100 meters)
TROPICAL (0-1000 meters)
Arid Tropical Scrub Forest (0-1000 meters)
Tropical Semi-deciduous Forest (150-600 meters)
The vegetation of the Pacific Coastal Plain and the Balsas-Tepalcatepec
Basin consists of arid tropical scrub forest, composed of deciduous
trees, which in many places are stunted and widely spaced. In the dry
season there is little cover provided by this forest. In the rainy
season there is a sparse growth of grasses and some shade provided by
the small leaves of the thorny trees.
In Michoacan the rainfall is heaviest on the southern slopes of the
Sierra de Coalcoman and somewhat less so on the southwestern slopes of
the Cordillera Volcanica. At these relatively low elevations (150 to 600
meters) there is tropical semi-deciduous forest, characterized by
relatively dense shade throughout the year and by a leaf mulch on the
ground. This type of forest forms the gallery forest along the larger
streams in the Balsas-Tepalcatepec Basin and on the Pacific Coastal
Plain.
Rainfall also is heavy on the high mountain ridges, where temperatures
are low. On these ridges, fir forest, often mixed with pine and oaks, is
found. This habitat is characterized by a cool, moist climate, many
rotting logs, and a moist ground cover of leaves and needles.
Most of the mountains are covered with pine-oak forest, which in most
places is decidedly subhumid, but where this forest occurs on the
windward sides of high ridges, it sometimes is noticeably humid. In
this forest the important animal habitats include the needle- and
leaf-litter, and in some areas, bromeliads.
The rolling terrain of the Mexican Plateau supports cacti, small
leguminous trees, and grasses. Like the arid tropical scrub forest, this
type of vegetation, the Mesquite-grassland association, is deciduous and
thus provides little shelter in the dry season. Unlike the areas in
which arid tropical scrub forest is developed, the Mesquite-grassland is
found in areas having warm days and cool nights.
GEOGRAPHY OF THE HERPETOFAUNA
Although the main part of my final report on the herpetofauna of
Michoacan will deal with the geographical and ecological patterns of
distribution of the herpetofauna, a brief summary of the faunal
assemblages is presented here.
In Michoacan there are two major faunal assemblages, one in the
lowlands, and one in the highlands. A large number of the species
inhabiting the lowlands are wide-ranging species, such as _Bufo
marinus_, _Iguana iguana_, and _Boa constrictor_. Sixty-three species
are known to occur on the Pacific Coastal Plain; 41 of these, together
with 36 others occur in the Balsas-Tepalcatepec Basin, a physiographic
region to which several species of reptiles are endemic; for example,
_Enyaliosaurus clarki_, _Urosaurus gadowi_, _Cnemidophorus calidipes_,
and _Eumeces altamirani_.
Generally speaking, the members of the highland faunal assemblage have
more restricted geographic ranges. The major exceptions are those
species that are widely distributed on the Mexican Plateau, such as:
_Bufo compactilis_, _Sceloporus torquatus_, and _Salvadora bairdi_. In
the montane habitats of the Cordillera Volcanica, 45 species of
amphibians and reptiles are known; 34 species have been found in the
Sierra de Coalcoman. Fourteen species are known to occur in both ranges.
Several species are known only from the Cordillera Volcanica and
adjacent highlands, and three species are endemic to the Sierra de
Coalcoman.
ANNOTATED LIST OF SPECIES
In the following pages the 176 species and subspecies of amphibians and
reptiles known to occur in the state of Michoacan are discussed in
relation to their variation, life histories, ecology, and distribution
in the state. Data have been gathered from 9676 specimens. I have not
prolonged the accounts of species with information that has been
presented elsewhere. Consequently, the length and completeness of the
accounts are variable. I have given only the information that I consider
a worthwhile contribution to our knowledge of the particular species.
The synonymies given at the beginning of each account include the first
use of the trivial name by the original author, the first usage of the
combination that I am using, and, if the circumstances make it
necessary, additional names or combinations that have been proposed
since the publication of the checklists of Mexican amphibians and
reptiles by Smith and Taylor (1945, 1948, and 1950b). References cited
only in the synonymies are not listed in the Literature Cited. Preceding
the discussion of each species is an alphabetical list of the localities
in Michoacan from which specimens have been examined. The listing of a
locality means that one or more specimens, as indicated, has been
examined from that locality. Only for those specimens especially
mentioned in the text are catalogue numbers given. Abbreviations for the
various museums and scientific collections are, as follows:
AMNH American Museum of Natural History
ANSP Academy of Natural Sciences of Philadelphia
BMNH British Museum (Natural History)
CNHM Chicago Natural History Museum
EHT-HMS Edward H. Taylor-Hobart M. Smith collection
JRD James R. Dixon collection, College Station, Texas
KU University of Kansas Museum of Natural History
MCZ Museum of Comparative Zoology
MVZ Museum of Vertebrate Zoology
NMW Naturhistorisches Museum Wien
SU Stanford University Museum of Natural History
TCWC Texas Cooperative Wildlife Collection
UIMNH University of Illinois Museum of Natural History
UMMZ University of Michigan Museum of Zoology
USNM United States National Museum
UTNHC University of Texas Natural History Collection
Throughout the accounts of the species all measurements are given in
millimeters; if the range of variation is given, the mean follows in
parentheses.
AMPHIBIA
Caudata
~Ambystoma amblycephalum~ Taylor
_Ambystoma amblycephala_ Taylor, Univ. Kansas Sci. Bull.,
26: 420, November 27, 1940.--Fifteen kilometers west of
Morelia, Michoacan, Mexico.
Fifteen km. W of Morelia (19); 11 km. SSE of Opopeo (12); 8
km. S of Patzcuaro; 24 km. S of Patzcuaro (2); Quiroga (20);
Tacicuaro (167).
Taylor and Smith (1945:530) presented data on 137 specimens collected at
Tacicuaro on October 1, 1939; these are all larvae and metamorphosing
individuals. Aside from these, the largest larva examined (UMMZ 104962
from 15 km. W of Morelia) has a snout-vent length of 70.0 mm. and a tail
length of 53.5 mm. The larvae are pale pinkish tan above and somewhat
paler below; there is a lateral row of cream colored spots. The
tail-fin, which is deepest at mid-length, extends to the back of the
head and is flecked with brown. In small larvae the outer edge of the
tail-fin is dark brown. The eyes are large. Two small metamorphosed
specimens (UMMZ 98967) from 24 kilometers south of Patzcuaro are
tentatively referred to this species. These specimens have body lengths
of 49.0 and 45.0 mm. and tail lengths of 36.0 and 31.5 mm.,
respectively. They have 17-17 and 16-15 vomerine teeth arranged in a
broad arch behind the choanae, 10 costal grooves, and 7 intercostal
spaces between adpressed toes. The dorsal color is uniform brown; that
of the venter is a dusty cream.
Larvae were collected from shallow ponds near Quiroga and 15 kilometers
west of Morelia; metamorphosed individuals were taken from beneath logs
in pine and fir forests at elevations from 2300 to 2800 meters.
~Ambystoma dumerili dumerili~ (Duges)
_Siredon Dumerili_ Duges, La Naturaleza, 1:241, 1870--Lago
de Patzcuaro, Michoacan, Mexico.
_Bathysiredon dumerilii_, Dunn, Notulae Naturae, 36:1,
November 9, 1939.
_Bathysiredon dumerilii dumerilii_, Maldonado-Koerdell, Mem.
y Rev. Acad. Nac. Cien., 56:199, 1948.
_Ambystoma_ (_Bathysiredon_) _dumerili_, Tihen, Bull.
Florida State Mus., 3:3, June 20, 1958.
Lago de Patzcuaro (22);? Morelia.
For many years this unusual salamander was known from only a few
specimens mostly collected in the last century; Smith and Taylor
(1948:7) stated: "It is presumed that this species is extinct owing to
the introduction of exotic game and food fishes." In 1951 and in 1955 I
had been told that _axolotls_ were sold in the market at Patzcuaro;
nevertheless, none was found on my visits there. In 1956 Charles M.
Bogert obtained several large specimens at the market in Patzcuaro.
These establish the continued existence of the salamander in Lago de
Patzcuaro. On January 27, 1955, R. W. Dickerman procured a specimen (KU
41573) in the market at Morelia. Since fish are brought to Morelia from
Lago de Patzcuaro, the specimen probably was from that lake.
Nevertheless, the species may occur in other permanent bodies of water
in Michoacan. Maldonado-Koerdell (1948) described _Bathysiredon dumerili
queretarensis_ from San Juan del Rio, Queretaro. This locality is about
200 airline kilometers northeast of Lago de Patzcuaro and is in the Rio
Moctezuma drainage.
~Ambystoma ordinarium~ Taylor
_Ambystoma ordinaria_ Taylor, Univ. Kansas Sci. Bull.,
26:422, November 27, 1940.--Four miles west of El Mirador,
near Puerto Hondo, Michoacan, Mexico.
Axolotl (56); Cerro San Andres; 22 km. W of Mil Cumbres; 46
km. E of Morelia (34); 8 km. SE of Opopeo (5); Puerto de
Garnica (8); Puerto Hondo (41); San Gregorio (16); San Jose
de la Cumbre (20).
Of 16 specimens (KU 51520-35) collected on June 18, 1955, near San
Gregorio, 15 are adult females with swollen cloacae and minute ovarian
eggs. Possibly these specimens had just recently deposited their mature
eggs. In preservative the specimens are black above and dull creamy gray
below. Measurements for the 15 females are: snout-vent length,
80.0-102.0 (92.5); tail length, 69.0-93.0 (84.2); head width, 15.8-20.5
(17.7); head length, 22.8-26.6 (24.4). A larval specimen with small
gills has a snout-vent length of 72 mm. and a tail length of 62 mm.
Three specimens have 12 costal grooves; the other have 11.
Of 20 specimens from San Jose de la Cumbre (UMMZ 112857 and 115143), 14
are neotenic adults; the others are larvae. In life the salamanders were
blackish to olive-brown above with scattered cream-colored dots on the
dorsum and flanks but in preservative are dull grayish black with
indistinct pale spots and dark reticulations. The belly is pale gray
with indistinct dark spots. Eleven females and three males have the
following measurements, respectively: snout-vent length, 76.0-90.0
(80.7), 64.0-84.0 (74.3); tail length, 70.0-81.0 (75.0), 58.0-71.0
(66.7); head width, 19.5-23.5 (20.7), 17.5-20.5 (19.3); head length,
22.0-25.0 (23.0), 20.0-22.5 (21.5). The smallest larva has a snout-vent
length of 43.0 mm. and a tail length of 38.0 mm. Two individuals have 12
costal grooves; the others have 11. All of the females contained eggs,
the largest of which were 1.5 mm. in diameter. The stomachs of most of
the specimens were distended with oligochaets, aquatic insect larvae,
and small aquatic beetles.
A series of 34 larvae (JRD 5904-37) from 46 kilometers east of Morelia
are tentatively referred to this species. These specimens are
olive-brown above with cream-colored spots on the flanks; the dorsal
tail-fin does not extend onto the body.
This species has been found only at elevations in excess of 2400 meters
in pine and fir forests. At Rancho Axolotl James A. Peters collected
larvae and neotenic individuals in a rocky stream and adults from
beneath rocks and logs in the forest near the stream. Neotenic
individuals and larvae were found in a clear stream in pine-fir forest
at an elevation of 2700 meters near San Jose de la Cumbre; specimens
were collected there in July, 1955, and again in July, 1956. The site
was visited in April, 1956, at which time the stream consisted of only a
few puddles; no salamanders were found.
~Ambystoma tigrinum velasci~ Duges
_Ambystoma velasci_ Duges, La Naturaleza, ser. 2, 1:142,
1888.--Laguna Santa Isabel, near Guadalupe Hidalgo, Distrito
Federal, Mexico.
_Ambystoma tigrinum velasci_, Dunn, Copeia, no. 3:157,
November 14, 1940.
Patzcuaro (5); Tacicuaro (9).
Definite specific assignment of these specimens, all larvae, cannot be
made at this time. They have shovel-shaped heads and laterally
compressed bodies with the dorsal tail-fin extending anteriorly to the
back of the head. The eyes are small. The body is pale tan with dark
mottling on the tail and flanks. The average snout-vent length for nine
specimens from Tacicuaro is 61.0 mm.
The larvae from Tacicuaro (UMMZ 89255) were collected by Dyfrig Forbes
in October, 1939; those from Patzcuaro, presumably Lago de Patzcuaro
(BMNH 1914.1.28-247-8 and CNHM 948), were collected by Hans Gadow and
Seth Meek in 1908.
~Pseudoeurycea belli~ (Gray)
_Spelerpes belli_ Gray, Catalogue Batrachia Gradientia
British Museum, p. 46, 1850.--Mexico. Type locality
restricted to 2 miles east of Rio Frio, Puebla, Mexico, by
Smith and Taylor (1950a:341).
_Pseudoeurycea bellii_, Taylor, Univ. Kansas Sci. Bull.,
30:209, June 12, 1944.
Axolotl (2); Carapan; Cerro Tancitaro (84); Macho de Agua;
22 km. W of Mil Cumbres; Opopeo; Patzcuaro (8); Puerto Hondo
(2): San Jose de la Cumbre; San Juan de Parangaricutiro
(42); Uruapan (5); Zacapu (4).
This salamander seems to reach its greatest abundance in Michoacan in
the Sierra de los Tarascos between Patzcuaro and Tancitaro, where it is
found at elevations from 1500 to 2900 meters. It is found less commonly
in the eastern part of the Cordillera Volcanica in Michoacan, where it
sometimes occurs in association with _Pseudoeurycea robertsi_.
On June 22 and 23, 1955, four clutches of eggs of this species were
found beneath adobe bricks and rocks on the volcanic ash that has buried
the village of San Juan de Parangaricutiro. The eggs were unstalked and
separate, but adherent in clumps of three or four (Pl. 2, Fig. 1). The
outer membranes were covered with fine particles of ash. The ash beneath
the stones where the eggs were found was only slightly moist; one clump
of eggs was partially desiccated. Three complete clutches have 20, 23,
and 34 eggs; one clutch of 15 eggs was being eaten by beetles
(Tenebrionidae: _Eleodes_ sp.). The eggs vary in size from 4.6 to 6.5
mm. and average 5.3 mm. in diameter. They are unpigmented. Surrounding
the embryo is a vitelline membrane, an inner, and an outer envelope
(Fig. 1). In an average-sized egg having an embryo 4 mm. in length, the
diameter of the outer membrane is 5.3 mm., the inner membrane 5.0 mm.,
and the vitelline membrane 4.6 mm. All of the eggs contained embryos in
which the limb buds were developed; in about half of these the eyes were
distinctly visible.
[Illustration: Fig. 1. Diagram of an egg of _Pseudoeurycea belli_ from
San Juan de Parangaricutiro, Michoacan. x 10.]
The first heavy rain of the season occurred on the night of June 22,
1955. Thus, at least sometimes, _Pseudoeurycea belli_ lays its eggs
before the onset of the rainy season. A female having a snout-vent
length of 110 mm., collected on June 22, 1955, contained 36 ovarian eggs
having diameters from 3.0 to 3.5 mm. The fact that small juveniles were
collected on the same date indicates that this salamander lays eggs over
a period of several weeks in late spring and early summer.
The smallest juvenile examined has a snout-vent length of 17.0 mm. and a
tail length of 7.5 mm. Twelve juveniles from the vicinity of San Juan de
Parangaricutiro have an average snout-vent length of 19.4 mm. and an
average tail length of 9.7 mm. In juveniles the adpressed limbs either
touch or overlap by one intercostal space; in adults there are two or
three intercostal spaces between adpressed toes. Therefore the greatest
number of intercostal spaces between adpressed limbs is found in the
largest specimens. A similar relationship between adpressed limbs (=
length of limbs) and snout-vent length was shown for _Plethodon
richmondi_ by Duellman (1954a). The number of vomerine teeth is
variable; the number of teeth seems to be closely correlated with the
size of the salamander (Fig. 2). A similar correlation between the
number of maxillary teeth and body length was reported for
_Chiropterotriton multidentatus_ by Rabb (1958). In 12 juvenile
_Pseudoeurycea belli_ there are 6-13 (8.8) vomerine teeth, and in 11
adults having snout-vent lengths greater than 90 mm. there are 39-49
(44.0) vomerine teeth. The coloration of the juveniles resembles that of
the adults (Pl. 1).
[Illustration: FIG. 2. Correlation between the number of vomerine teeth
and snout-vent length in 79 _Pseudoeurycea belli_ from Michoacan.]
The differences between this species and _Pseudoeurycea gigantea_ are
minor. Taylor (1939a) distinguished _gigantea_ from _belli_ by the
larger size, fewer intercostal spaces between adpressed limbs, more
vomerine teeth, and absence of occipital spots in _gigantea_. Taylor and
Smith (1945) stated that in life the spots in _gigantea_ are orange
instead of red as in _belli_. Five specimens of _Pseudoeurycea belli_
from Michoacan, including one juvenile, lack occipital spots. In the 34
living individuals that I have seen from Michoacan the spots varied from
deep red to orange. Therefore, of the characters listed by Taylor (_op.
cit._) to diagnose _Pseudoeurycea gigantea_, only the over-all larger
size and smaller number of intercostal spaces between adpressed limbs (=
relatively longer limbs) are useful in separating _Pseudoeurycea belli_
and _gigantea_.
~Pseudoeurycea robertsi~ (Taylor)
_Oedipus robertsi_ Taylor, Univ. Kansas Sci. Bull., 25:287,
July 10, 1939.--Nevado de Toluca, Mexico.
_Pseudoeurycea robertsi_ Taylor, Univ. Kansas Sci. Bull.,
30:209, June 12, 1944.
Atzimba (3); Macho de Agua (9); Puerto Lengua de Vaca (14).
Previously this species has been recorded only from the type locality.
In July, 1956, individuals referable to this species were found at two
sites in pine-fir forest immediately to the east of Macho de Agua and in
pine-oak-fir forest at Atzimba. On August 20, 1958, a series was
collected in pine-fir forest at Puerto Lengua de Vaca. These localities
are between 2900 and 3000 meters in the Cordillera Volcanica in eastern
Michoacan.
In life the coloration of these salamanders was highly variable. The
belly and undersurfaces of the tail and hind limbs were pale gray, with
or without silvery white flecks; the chin was a cream-color and flecked
with silvery white in some specimens. The middorsal area was brown,
orange-brown, or dull grayish yellow. The flanks and lateral surfaces of
the tail were black with yellowish flecks or streaks on the flanks and
yellowish or orange-brown flecks on the tail. The iris was golden brown.
Measurements of eight males and two females are, respectively:
snout-vent length, 42.5-56.0 (49.5), 54.0-60.0 (57.0); tail length,
42.0-56.0 (48.1), 52.0-55.0 (53.5). The smallest juvenile has a
snout-vent length of 28.0 mm. and a tail length of 23.0 mm. Of the 26
available specimens, six have 12 costal grooves, and the others have 11.
In comparison with 36 topotypes, the specimens from Michoacan have a
less striking dorsal color pattern; none has a well-defined dorsal
reddish brown area or bold reddish mottling on the tail. Furthermore,
the specimens from Michoacan have paler venters than do topotypic
specimens.
Salientia
~Rhinophrynus dorsalis~ Dumeril and Bibron
_Rhinophrynus dorsalis_ Dumeril and Bibron, Erpetologie
generale, vol. 8:758, 1841.--Veracruz, Veracruz, Mexico.
Mouth of the Rio Balsas (10).
These specimens (BMNH 1914.1.28.181-90) were collected by Gadow in 1908
and reported by him (1930:72): "Whilst this very sluggish termite-eating
toad is common enough in the sweltering hot country of the state of Vera
Cruz, up to an elevation of 1500 feet, it was unknown on the west side
of the Isthmus until I found it in great numbers near the mouth of the
Balsas River, in and near fresh-water pools, where it attracted
attention by its loud peculiar voice during the pairing season in the
month of July." Subsequently, Peters (1954:3) verified the
identification of these specimens. Although torrential rains fell during
the week in July, 1955, that I spent at Playa Azul near the mouth of the
Rio Balsas, the distinctive voice of _Rhinophrynus_ was not heard.
Elsewhere on the Pacific coast of Mexico adult _Rhinophrynus_ have been
reported only from Tehuantepec and a few localities on the coastal
lowlands of Chiapas. Taylor (1942b:37) found on the coast of Guerrero a
tadpole that was referred to the genus _Rhinophrynus_ by Orton (1943).
In the summer of 1960 adults of _Rhinophrynus_ were collected near
Acapulco, Guerrero (Fouquette, _in litt._). These recent collections
verify the existence of the species along the Pacific lowlands of Mexico
at least as far north as Michoacan.
~Scaphiopus hammondi multiplicatus~ Cope
_Scaphiopus multiplicatus_ Cope, Proc. Acad. Nat. Sci.
Philadelphia, 15:52, June 8, 1863.--Valley of Mexico.
_Scaphiopus hammondi multiplicatus_, Kellogg, Bull. U. S.
Natl. Mus., 160:22, March 31, 1932.
Angahuan (5); Cuitzeo (4); Cuseno Station (2); Jiquilpan
(9); Morelia (7); Patzcuaro (3); Quiroga; Tarecuaro; Uruapan
(24); Zacapu.
This small toad has been found at elevations between 1500 and 2500
meters on the Mexican Plateau and associated mountain ranges; it occurs
in mesquite-grassland and in pine forests. Calling males and females
laden with eggs have been collected in the rainy season in the months of
July and August. The call is a medium-pitched snore. In living
individuals the dorsal ground color varies from pale brown to gray with
dark brown or olive-brown markings. In many individuals the tips of the
small dorsal pustules are red.
~Bufo coccifer~ Cope
_Bufo coccifer_ Cope, Proc. Acad. Nat. Sci. Philadelphia,
18:130, 1866--Arriba, Costa Rica.
Apatzingan (27); Lombardia; Nueva Italia (5).
In life the dorsal color pattern consists of a yellowish tan ground
color with dark brown spots; the middorsal stripe is deep yellow or
cream color. The venter is a dusty cream color, and the iris is pale
gold. Males have dark brown horny nuptial tuberosities on the thumb. The
following measurements are of 21 males and four females, respectively:
snout-vent length, 43.5-51.7 (48.1), 55.6-62.6 (59.1); tibia length,
16.6-18.8 (17.6), 18.8-20.3 (19.3); head width, 16.7-19.7 (18.4),
20.6-22.2 (21.4); head length, 13.8-16.6 (14.8), 16.5-18.2 (17.3).
The specimens from the Tepalcatepec Valley differ slightly from
specimens from southeastern Mexico and Central America. Those from
Michoacan have low and narrow cranial crests; in about one-half of the
specimens the occipital crest exists only as a row of tubercles, and in
some the postorbital and suborbital crests are barely discernible.
Specimens from the southern part of the range, Costa Rica and Nicaragua,
have much higher and thicker cranial crests; in these the occipital
crest is well defined and extends posteriorly to a point back of the
anterior edge of the parotid gland; the postorbital and suborbital
crests are well marked. Of 48 specimens from Esquipulas, Guatemala, all
have high crests, but these are not so well developed as in ten
specimens from Matagalpa, Nicaragua, and three from various localities
in Costa Rica. Six specimens from Tehuantepec, Oaxaca, have cranial
crests that are lower than those in specimens from Guatemala. In three
of the specimens from Tehuantepec the occipital crests are reduced to a
series of tubercles. Of six specimens from Agua del Obispo, Guerrero,
four have poorly developed occipital crests. These observations suggest
the presence of a cline in the development of the cranial crests;
specimens have higher crests in the southern part of the range than in
the northern part.
In Mexico _Bufo coccifer_ has been collected only in semi-xeric
habitats, but to the south, from Guatemala to Costa Rica, it has been
found in more upland and humid habitats. Southern specimens are darker
than those from the north, a possible correlation with the differences
in habitat.
These toads probably range throughout the Tepalcatepec Valley, but they
are unknown from the coast of Michoacan. Breeding choruses were found
after heavy rains on June 24, 1955, and on August 2, 1956. The first was
in a muddy ditch; the second was in a flooded grassy field. The call is
a high-pitched, but not loud, "whirrr." Males were calling from the edge
of the water or from clumps of grass in the water. Clasping pairs were
in the water; amplexus is axillary.
~Bufo compactilis compactilis~ Wiegmann
_Bufo compactilis_ Wiegmann, Isis von Oken, 26:661,
1833.--Mexico. Type locality restricted to Xochimilco,
Distrito Federal, Mexico, by Smith and Taylor (1950a:330).
_Bufo compactilis compactilis_, Smith, Herpetologica, 4:7,
September 17, 1947.
Cuitzeo (2); Emiliano Zapata (20); Jiquilpan (5); La Palma
(5); Morelia; Tupataro.