Published in the United States of America

2013 • VOLUME 7 • NUMBER 1

AMPHIBIAN & REPTILE

CONSERWION

SPECIAL MEX CO ISSUE

amphibian-reptile-conservation.org

ISSN: 1083-446X

elSSN: 1525-9153

Editor

Craig Hassapakis

Berkeley, California, USA

Associate Editors

Raul E. Diaz Howard O. Clark, Jr. Erik R. Wild

University of Kansas, USA Garcia and Associates, USA University of Wisconsin-Stevens Point, USA

Assistant Editors

Alison R. Davis

University of California, Berkeley, USA

Daniel D. Fogell

Southeastern Community College, USA

Editorial Review Board

David C. Blackburn

California Academy of Sciences, USA

C. Kenneth Dodd, Jr.

University of Florida, USA

Harvey B. Lillywhite

University of Florida, USA

Peter V. Lindeman

Edinboro University of Pennsylvania, USA

Jaime E. Pefaur

Universidad de Los Andes, VENEZUELA

Jodi J. L. Rowley

Australian Museum, AUSTRALIA

Bill Branch

Port Elizabeth Museum, SOUTH AFRICA

Lee A. Fitzgerald

Texas A&M University, USA

Julian C. Lee

Taos, New Mexico, USA

Henry R. Mushinsky

University of South Florida, USA

Rohan Pethiyagoda

Australian Museum, AUSTRALIA

Peter Uetz

Virginia Commonwealth University, USA

Jelka Crnobrnja-Isailovc

IBISS University of Belgrade, SERBIA

Adel A. Ibrahim

Ha’il University, SAUDIA ARABIA

Rafaqat Masroor

Pakistan Museum of Natural History, PAKISTAN

Elnaz Najafimajd

Ege University, TURKEY

Nasrullah Rastegar-Pouyani

Razi University, IRAN

Larry David Wilson

Institute Regional de Biodiversidad, USA

Allison C. Alberts

Zoological Society of San Diego, USA

Michael B. Eisen

Public Library of Science, USA

Advisory Board

Aaron M. Bauer

Villanova University, USA

James Hanken

Harvard University, USA

Walter R. Erdelen

UNESCO, FRANCE

RoyW. McDiarmid

USGS Patuxent Wildlife Research Center, USA

Russell A. Mittermeier

Conservation International, USA

Robert W. Murphy

Royal Ontario Museum, CANADA

Eric R. Pianka

University of Texas, Austin, USA

Antonio W. Salas

Environment and Sustainable Development, PERU

Dawn S. Wilson

AMNH Southwestern Research Station, USA

Honorary Members

Carl C. Gans Joseph T. Collins

( 1923 - 2009 ) ( 1939 - 2012 )

Cover :

Upper left: Bolitoglossa franklini. Photo by Sean Rovito.

Upper right: Diaglena spatulata. Photo by Oscar Medina Aguilar.

Center left: Agkistrodon bilineatus. Photo by Chris Mattison.

Center right: Trachemys gaigeae. Photo by Vicente Mata-Silva.

Lower left: Heloderma horridum. Photo by Tim Burkhardt.

Lower right: Cerro Mariana, Balsas-Tepalcatepec Depression, ca. 12 km NW of Caracuaro, Michoacan.

Photo by Javier Alvar ado -Diaz.

Amphibian & Reptile Conservation — Worldwide Community-Supported Herpetological Conservation (ISSN: 1083-446X; elSSN: 1525-9153) is

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bution, conservation, species profiles, ecology, natural history, sustainable management, conservation breeding, citizen science, social network-

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Amphibian & Reptile Conservation 7(1): /-//.

PREFACE

AMPHIBIAN & REPTILE CONSERVATION

SPECIAL MEXICO ISSUE

Citation: Wilson LD. 2013. Preface ( Amphibian & Reptile Conservation Special Mexico Issue). Amphibian & Reptile Conservation 7(1):

The allure of Mexico first beckoned me in 1957, but only

from across the border, as along with my parents and

sister I was visiting family members in Mission, Texas.

Mission is a bit west of McAllen, just north of the interna-

tional border, with Reynosa located on the southern bank

of the Rio Bravo directly across from McAllen. We went

to Reynosa just to say we had been in Mexico.

My first herpetological trip to Mexico occurred in

1966, when Ernest A. Liner kindly took me on one of his

many journeys. We traveled as far south as Chiapas, and

saw much of the country and plenty of amphibians and

reptiles.

In the ensuing years, I traveled south of the border on

several occasions, and ultimately visited all but one of

Mexico’s 31 states. Among several others, 1 took one of

those trips with Louis Porras, the senior author of the pa-

per on cantils in this issue. I made another extensive trip

with my father, Ward Wendell Wilson, and visited many

of the ancient ruins for which the country is well known.

During my career I have always been interested in

Mexico, although in recent years I spent much of my

time in Central America. Nevertheless, I was delighted

at the opportunity to work on the book Conservation of

Mesoamerican Amphibians and Reptiles (2010), which

dealt with all of Mexico and Central America. This mas-

sive undertaking presented me with the chance to work

closely with two long-time friends, Jerry Johnson, one of

my co-editors, and Louis Porras, the proprietor of Eagle

Mountain Publishing, LC, and both are involved in this

Special Mexico Issue.

The herpetofauna of Mexico is impressive from a

number of perspectives. At 1,227 species, it is almost

twice the size of that of its northern neighbor (presently,

the United States is known to contain 628 native species,

according to the Center for North American Herpetol-

ogy [naherpetology.org]; data accessed 17 March 2013);

Mexico, however, is only about one-fifth the size of the

United States. Mexico’s herpetofauna also is larger than

that of the seven Central American nations combined

(1,024 native species, according to Wilson and Johnson

[2010], and my updating since), although the disparity be-

tween Mexico and its southern neighbors is much smaller.

Notably, Central America’s land area is slightly over one-

fourth that of Mexico.

amphibian-reptile-conservation.org

The level of endemicity in Mexico also is spectacu-

lar. In this Special Mexico Issue, Wilson, Mata-Silva, and

Johnson report that 482 species of reptiles (excluding

the marine species) of a total of 849 (56.8%) are Mexi-

can endemics; Wilson, Johnson, and Mata-Silva indicate

that 253 species of amphibians of a total of 378 (66.9%)

are not found outside of Mexico. The combined figure is

736 endemics out of 1,227 species (60.0%), a percent-

age substantially higher than that for Central America.

In Central America, 367 endemic species have been re-

corded to date (Wilson and Johnson [2010], and my up-

dating since), which equates to 35.8%. According to the

accounting at the Center for North American Herpetol-

ogy website (www.cnah.org), however, compared to the

figures for Mexico (see the two Wilson et al. papers in-

dicated below), Canada (www.carcnet.ca) and the West

Indies (Powell and Henderson 2012), of the 628 species

listed, 335 are endemic to the United States, for which

the resulting percentage (53.3%) is much closer to that

of Mexico than for Central America. Because the United

States is about five times the size of Mexico, when one

compares the degree of endemism in these two countries

with their respective land areas (area/number of endem-

ics), the resulting figures (areas from the CIA World Fact-

book; www.cia.gov) are as follows: Mexico (1,943,945

km 2 /736 = 2,641); and the United States (9,161,966

km 2 /335 = 25,808). Thus, the area/endemism ratio for the

United States is almost 10 times that of Mexico, indicat-

ing that endemism in Mexico is that much greater than

that of its neighbor to the north. The comparable figure

for Central America is 507,966 km 2 /367 = 1,384, which is

even lower than that for Mexico, and this region already

is regarded as a major source of herpetofaunal diversity

(Wilson et al. 2010).

The Mexican herpetofauna also is of immense impor-

tance and interest from a conservation standpoint. In both

of the Wilson et al. papers indicated below, the authors

applied the Environmental Vulnerability Score (EVS)

measure to Mexico’s herpetofauna and found that 222

of 378 amphibian species (58.7%) and 470 of 841 rep-

tile species in (55.9%) were assigned an EVS that falls

into the high vulnerability category. In total, 692 species

(56.8%) fall into the highest category of susceptibility to

environmental deterioration. The relatively small portion

/ June 2013 I Volume 7 | Number 1 | e62

Preface

of humanity that recognizes the value and critical neces-

sity of biodiversity is fighting an uphill battle to salvage

as much biodiversity as possible before it disappears into

extinction (Wilson 2006). Given the rate of human popu-

lation growth and the commensurate rate of loss of natu-

ral habitats, populations of these unique components of

the Mexican patrimony likely will decline steadily, as is

happening over the remainder of the planet (Raven et al.

2011 ).

One of the most important imperatives we face, there-

fore, is to take appropriate steps to conserve the Mexican

herpetofauna. Toward this end, five papers collectively

written by 10 contributors are expected to appear in this

Special Mexico Issue of Amphibian & Reptile Conserva-

tion. These papers are as follows:

A conservation reassessment of the reptiles of Mexico

based on the EVS measure by Larry David Wilson,

Vicente Mata-Silva, and Jerry D. Johnson.

A taxonomic reevaluation and conservation assess-

ment of the common cantil, Agkistrodon bilinea-

tus (Squamata: Viperidae): a race against time by

Louis W. Porras, Larry David Wilson, Gordon W.

Schuett, and Randall S. Reiserer.

Patterns of physiographic distribution and conserva-

tion status of the herpetofauna of Michoac an, Mex-

ico by Javier Alvarado-Diaz, Ireri Suazo-Ortuno,

Larry David Wilson, and Oscar Medina- Aguilar.

Taxonomic reevaluation and conservation of beaded

lizards, Heloderma horridum (Squamata: Helo-

dermatidae) by Randall S. Reiserer, Gordon W.

Schuett, and Daniel D. Beck.

A conservation reassessment of the amphibians of

Mexico based on the EVS measure by Larry David

Wilson, Jerry D. Johnson, and Vicente Mata-Silva.

All of these papers deal with issues of herpetofaunal con-

servation, and range in coverage from the entire country

of Mexico, through a single Mexican state, to what have

been regarded as single species. Each study provides a set

of recommendations.

These five papers are gathered under this Preface and

an issue cover. The concept behind the cover is to draw

the papers into a coherent whole that reinforces the mis-

sion of the journal, which is to “support the sustainable

management of amphibian and reptile biodiversity.”

Thus, the photograph of Cerro Mariana, located in the

Balsas-Tepalcatepec Depression between Huetamo and

Morelia, in Michoacan, is intended to illustrate dry forest,

the type of vegetation most heavily damaged in Meso-

america (Janzen 1988), one of the major features of the

state’s environment and in which a significant portion of

the herpetofauna is found. This type of environment is

amphibian-reptile-conservation.org

inhabited by two of the reptiles featured in this issue, the

common cantil (Agkistrodon bilineatus ) and the beaded

lizard (Heloderma horridum ), as well as the shovel-head-

ed treefrog (Diaglena spatulataf all three of these species

are relatively broadly distributed in subhumid environ-

ments along the Pacific coastal region of Mexico, as well

as in the extensive valley of the Balsas and Tepalcatepec

rivers, of which the western portion lies in the state of

Michoacan.

Finally, our aim is to examine the conservation status

of the amphibians and reptiles of Mexico, in general, and

to focus more closely on a state herpetofauna (of Micho-

acan) and on two prominent and threatened Mexican flag-

ship species, the common cantil and the beaded lizard.

Thus, we hope to contribute to the ongoing effort to pro-

vide for a sustainable future for the world’s amphibians

(Stuart et al. 2010) and reptiles (Bohm et al. 2013).

Literature Cited

Bohm M et al. 2013. The conservation status of the

world’s reptiles. Biological Conservation 157: 372-

385.

Janzen DH. 1988. Tropical dry forests: the most en-

dangered major tropical ecosystem. Pp. 130-137 In:

Biodiversity. Editor, Wilson EO. National Academy

Press, Washington, DC, USA.

Powell R, Henderson RW (Editors). 2012. Island lists of

West Indian amphibians and reptiles. Florida Museum

of Natural History Bulletin 51 : 85—166.

Raven PH, Hassenzahl DM, Berg LR. 2011. Environ-

ment (8 th edition). John Wiley & Sons, Inc., Hoboken,

New Jersey, USA.

Stuart SN, Chanson JS, Cox NA, Young BE. 2010. The

global decline of amphibians: current trends and fu-

ture prospects. Pp. 2-15 In: Conservation of Meso-

american Amphibians and Reptiles. Editors, Wilson

LD, Townsend JH, Johnson JD. Eagle Mountain Pub-

lishing, LC, Eagle Mountain, Utah, USA.

Wilson, EO. 2006. The Creation: An Appeal to Save Life

on Earth. W. W. Norton & Company, New York, New

York, USA.

Wilson LD, Johnson JD. 2010. Distributional patterns

of the herpetofauna of Mesoamerica, a biodiversity

hotspot. Pp. 30-235 In: Conservation of Mesoameri-

can Amphibians and Reptiles. Editors, Wilson LD,

Townsend JH, Johnson JD. Eagle Mountain Publish-

ing, LC, Eagle Mountain, Utah, USA.

Wilson LD, Townsend JH, Johnson JD. 2010. Conserva-

tion of Mesoamerican Amphibians and Reptiles. Ea-

gle Mountain Publishing, LC, Eagle Mountain, Utah,

USA.

Larry David Wilson

2 May 2013

ii June 2013 | Volume 7 | Number 1 | e62

mons Attribution-NonCommercial-NoDerivs 3.0 Unported License, which permits unrestricted use for non-com-

mercial and education purposes only provided the original author and source are credited.

Amphibian & Reptile Conservation 7(1): iii-vi.

DEDICATIONS

Citation: Johnson JD, Porras LW, Schuett GW, Mata-Silva V, Wilson LD. 2013. Dedications ( Amphibian & Reptile Conservation Special Mexico Issue).

Amphibian & Reptile Conservation 7(1): iii-vi.

With the publication of this Special Mexico Issue (SMI),

the contributing authors were provided with an opportu-

nity to dedicate it to herpetologists who have played a sig-

nificant role in their lives, as well as the lives of other her-

petologists past and present. Each of the 10 contributors

was asked to identify the person who was most influential

in their respective careers, especially with respect to what

each of them has contributed to SMI. The dedicatees are:

Miguel Alvarez del Toro.

Miguel Alvarez del Toro (August 23, 1917-August 2,

1996) was bom in the city of Colima, Colima, Mexico,

according to an obituary in Herpetological Review by Os-

car Flores-Villela and Wendy Hodges in 1999. He moved

to Mexico City in 1932, where he attended and later grad-

uated from high school. Although his formal education

was limited, his repute as an avid naturalist spread rapidly

and at the age of 21, while still in Mexico City, he began

a long career devoted to a multitude of zoological and

conservation related disciplines. He moved to Chiapas in

1942, and after a short stint as keeper and curator became

the Director of what then was known as the Instituto de

Historia Natural located near downtown Tuxtla Gutierrez.

His reputation grew exponentially because of his tireless

work at the Zoological Park and Natural History Muse-

um, his publication record, including books and papers on

numerous vertebrate and invertebrate groups, and his sol-

emn activism on conservation issues. One of his greatest

legacies was convincing several generations of politicians

in Chiapas to help develop a system of natural protected

areas, and also to expand the Zoological Park and move it

to “El Zapotal,” a relatively pristine site on the southern

edge of the city. That new and remarkable facility was

s .

named “Zoologico Regional Miguel Alvarez del Toro, or

ZOOMAT as it is popularly called today. Because of his

lifetime efforts, “Don Miguel,” as he was called respect-

fully, was justly awarded honorary doctoral degrees from

the Universidad de Chapingo, in 1992, and from the Uni-

versidad Autonomo de Chiapas, in 1993. Over his long

career he received a plethora of other awards, and also

was involved in numerous conservation projects in con-

junction with various local, state, national, and interna-

tional organizations.

Jerry D. Johnson, an avid “herper” since grade school

and recently discharged from the Marine Corps after a

stint in Viet Nam, enrolled in the 1971 wintermester

course at Fort Hays State University (Kansas), and ac-

companied Dr. Charles A. Ely to Chiapas on a migratory

bird study. Dr. Ely, after recognizing Johnson’s eagerness

to search for amphibians and reptiles through all sorts

of tropical and highland environments, included him on

many return trips during the next several years. On that

initial 1971 trip, Johnson briefly met Don Miguel at the

old Zoological Park. In 1974, Dr. Ely arranged for he and

Johnson to pitch tents in Don Miguel’s back yard, located

near the Zoo. This initiated an opportunity to mingle with

s

all sorts of interesting people, including the Alvarez del

Toro family, their friends, and a continuous flow of trav-

eling naturalists who were visiting the Zoo. During those

times Johnson realized just how influential Don Miguel’s

scientific and conservation work had become, in Chiapas

and elsewhere. On a typical day, Don Miguel often would

walk among the Zoological Park’s animal enclosures, and

during those walks Jerry came to know him while dis-

cussing the status of herpetology in Chiapas, how con-

servation efforts were in dire straits, and pondering his

doubts about the possibility that anything resembling a

natural Chiapas would persist into the future. In 1985,

Don Miguel published a book entitled \Asi Era Chiapasl

that described how Chiapas had changed in the 40 years

since he had arrived in the state. Even today, Johnson of-

ten thinks about how habitat destruction had altered the

Chiapan environment since he began investigations there

in 1971, as a college sophomore. He now realizes that

his life and professional experiences have passed rather

quickly, but sadly, environmental decay is accelerating

at an even greater pace. Johnson now concentrates much

of his professional efforts on conservation issues, hoping

that humankind can avoid total environmental devasta-

tion. Jerry also is reasonably sure that Don Miguel really

didn’t expect preservation efforts to be very successful,

amphibian-reptile-conservation.org

Hi

June 2013 I Volume 7 | Number 1 | e64

Dedications

but he didn’t give up his dream of a more conservation-

oriented populace by continually teaching people why

preserving natural habitats is important to their own well-

being, which probably is the only way conservation will

ever succeed. With great pleasure, Johnson dedicates his

contributions to this special Mexico edition of Amphib-

s

ian and Reptile Conservation to Miguel Alvarez del Toro,

who in his opinion was the leading advocate and pioneer

of biodiversity conservation in 20 th century Mexico.

Roger Conant in his early 20s.

Roger Conant (May 6, 1909-December 19, 2003) was

born in Mamaroneck, New York, USA. As a child he de-

veloped a passion for reptiles, especially snakes, and at

the age of 19 became the Curator of Reptiles at the Tole-

do Zoo. After assembling a sizeable collection of reptiles

for public display, he was promoted to General Curator.

Because of the close proximity of Toledo to Ann Arbor,

he occasionally would visit herpetologists at the Univer-

sity of Michigan and became close friends with a then-

graduate student, Howard K. Gloyd. Eventually, Roger

left Toledo to become the Curator of Herpetology at the

Philadelphia Zoo, and in time became the zoo’s Director.

Throughout his 38-year career at Philadelphia he partici-

pated in weekly radio shows, edited the zoo’s publica-

tions, and made frequent television appearances. During

this time he also helped establish the Philadelphia Herpe-

tological Society, served as President of the Association

of Zoological Parks and Aquariums, and as President of

the American Association of Ichthyologists and Herpe-

tologists. In 1947 Roger married Isabelle Hunt Conant,

an accomplished photographer and illustrator who had

been working at the zoo for several years, and during the

following two decades the couple made several collecting

trips to Mexico. Roger’s first of 240 scientific publica-

tions (including 12 books) came at the age of 19; about a

decade later he authored The Reptiles of Ohio, a landmark

amphibian-reptile-conservation.org

book that set the standard for state herpetological publi-

cations. Roger perhaps is best known as the author of the

best selling book in herpetological history, A Field Guide

to the Reptiles and Amphibians of Eastern North Ameri-

ca, which was illustrated by Isabelle. The book was pub-

lished in 1958, and expanded versions followed in 1975,

1991, and 1998. For the majority of amphibian and reptile

enthusiasts and herpetologists living in the eastern part of

the United States during those years, this book became

their bible. In 1973, Roger retired early from the Philadel-

phia Zoo, after Isabelle had become ill. The Conants then

moved to Albuquerque, where Roger became an adjunct

professor at the University of New Mexico and devoted

much of his time to herpetology. Isabelle passed away

in 1976, and soon after Roger discovered that his close

friend, Howard K. Gloyd, was terminally ill. Howard had

been busy working on a project that he and Roger started

in 1932, and because of Howard’s deteriorating condi-

tion Roger made an enormous commitment and assured

Howard that the project would be completed. This hugely

important contribution, entitled Snakes of the Agkistro-

don Complex: a Monographic Review, was published

by the Society for the Study of Amphibians and Reptiles

(SSAR) in 1990. During this time Roger also was busy

writing his memoirs, A Field Guide to the Life and Times

of Roger Conant, which was published in 1997 by Selva,

and details his remarkable life and illustrious career.

Roger Conant in Santa Rosa National Park,

Costa Rica (1982).

Louis W. Porras and Gordon W. Schuett, two very

close friends of Roger’s, were involved at several levels

with the Agkistrodon monograph and Roger’s autobiog-

raphy. Because of their mutual interest in Agkistrodon, in

January of 1982 the trio traveled to Costa Rica in search

of cantils and although no individuals were found in the

iv June 2013 | Volume 7 I Number 1 | e64

Dedications

field, they managed to secure preserved specimens for

study. In July of that year, Porras returned to Costa Rica

with John Rmdfleish and collected what became the holo-

type of Agkistrodon bilineatus howardgloydi. Additional

information on the life of Roger Conant appears in an

obituary published in the June 2004 issue of Herpetologi-

cal Review. Among several solicited tributes indicating

how Roger had affected his colleague’s lives and careers,

Porras wrote the following summary:

As a giant in herpetology, no doubt many will be writing

about Roger Conant ’s amazing organizational skills, at-

tention to detail, literary contributions, lifelong produc-

tivity, and so on. From a personal perspective, however,

Roger was my friend, mentor, and father figure. He en-

riched my life in so many ways, and it would warm his

heart to know that by simply following his example, he

will continue to do so.

Schuett summarized his tribute as follows:

In reflection, I have no doubt that Roger Conant pos-

sessed genius. His was not displayed in eccentric man-

nerisms and arrogant actions, but in a subtle and quiet

ability to collect, organize, and process information for

large-scale projects. In his research, each and every de-

tail was painstakingly considered. Roger’s vast achieve-

ments are even more remarkable knowing that he was

largely self-educated. If genius is measured by the degree

to which one’s ideas and work influence others, Roger

stands among the giants of knowledge. . . Cheers to you,

Roger, to your remarkable and enviable life.

Yes, Indeed!

Aurelio Ramfrez-Bautista was bom in Xalapa, Vera-

cruz, Mexico, and today is a professor and biological in-

vestigator at the Universidad Autonoma del Estado de Hi-

dalgo. Dr. Ramfrez-Bautista has authored or co-authored

more than 100 publications, including five books and

40 book chapters, made numerous presentations on the

ecology and conservation of the Mexican herpetofauna,

and has become one of the leading herpetologists in the

country. During his many years as an educator and re-

searcher, Dr. Ramfrez-Bautista advised numerous bache-

lor, master, and doctoral students. Vicente Mata-Silva met

Dr. Ramfrez-Bautista in the summer of 1998, as an un-

dergraduate student working on his thesis on the herpeto-

fauna of a portion of the state of Puebla. They developed

a friendship, and through Dr. Ramirez-Bautista’s mentor-

ing Vicente developed a passion for Mexican herpetolo-

gy, especially Chihuahuan Desert reptiles, that continued

throughout his undergraduate studies and later through

master’s, doctoral, and post-doctoral work in the Ecology

and Evolutionary Biology program at the University of

Texas at El Paso. They have continued to work on sig-

nificant research projects on the conservation and ecology

of the Mexican herpetofauna. Vicente is extremely grate-

amphibian-reptile-conservation. org

Aurelio Ramfrez-Bautista in Chamela, Jalisco (2011).

ful to Dr. Ramfrez-Bautista for his farsighted and life-al-

tering introduction to herpetology. Their association has

led to a lifetime friendship, and a road of excitement and

opportunities that Vicente never envisioned possible. Dr.

Ramfrez-Bautista is the epitome of what an educator and

mentor should be, providing students the opportunity to

become professional scientists working in a world sorely

in need of commitment to environmental sustainability.

Hobart M. Smith in Mexico (1930).

Hobart Muir Smith (September 26, 1912-March 4,

2013) was bom Frederick William Stouffer in Stanwood,

Iowa, USA. At the age of four, he was adopted by Charles

and Frances Smith; both of his adoptive parents died,

however, before Dr. Smith finished college at Kansas

State University (KSU). In the engaging “historical per-

spective” written by David Chiszar, Edwin McConkey,

i/ June 2013 | Volume 7 | Number 1 | e64

Dedications

and Margaret M. Stewart and published in the 2004(2)

issue of Copeia, the authors recount an amazing story in-

dicating that when Dr. Smith (HMS) was in his senior

year in high school he was plagued by tachycardia and

an allergy to caffeine, which ended his interest in running

and led to youthful resolution that they reported as fol-

lows: “If I’m gonna do anything worthwhile, I had better

get to it, because I not gonna live very long” (!). Upon

completing high school, he headed for KSU with expecta-

tions of a major in entomology. A fortunate meeting with

Howard K. Gloyd, a somewhat older student who was

majoring in herpetology, brought HMS a change of heart,

however, and he became determined to study amphibians

and reptiles. He made this decision after having traveled

to the American West on collecting trips with Dr. Gloyd,

whose association with Dr. Conant is discussed above.

Gloyd and his major professor at the University of Michi-

gan, Dr. Frank Blanchard, suggested that HMS contact

Edward H. Taylor at the University of Kansas (KU). As

noted by Chiszar et al. (2004: 419), “this was probably the

act that cinched HMS to a herpetological orientation and

kiboshed entomology.” In fact, these authors also claim

that “HMS literally collected his BA and moments later

hopped into Taylor’s car bound for Mexico,” and that “the

rest is history.”

Hobart M. Smith and Rozella B. Smith at the

University of Wyoming (1960).

In 1940 (Wilson’s birth year), at age 26, he married

Rozella Pearl Beverly Blood, who he met while both

were graduate students at KU. Their marriage endured

until Rozella’s death in 1987. Dr. Smith began working

in Mexico in 1932, before any of the SMI contributors

was born, and those early collecting trips instilled a life-

long dedication for studying the Mexican herpetofauna.

Other collecting ventures followed during the remainder

of the decade. The material assembled during these trips

allowed him to begin a life-long journey to record the

composition, distribution, and systematics of the amazing

Mexican herpetofauna. During his long life he authored

more than 1,600 publications, including 29 books — the

greatest output in the history of herpetology. Chiszar et al.

(2004: 421-422) indicated that HMS was most proud of

the three Mexican checklists, the Sceloporus monograph,

the Handbook of Lizards, the comparative anatomy text-

book (which Wilson used when he took the course under

HMS), the Synopsis of the Herpetofauna of Mexico, the

Pliocercus book, and the Candoia monograph. In 1947,

HMS became a professor of zoology at the University of

Illinois at Urbana-Champaign, and remained there until

1968. During this period in his career, one of the SMI

contributors came under his influence. In 1958, Larry Da-

vid Wilson graduated from Stephen Decatur High School

in Decatur, Illinois, and the following year enrolled at

Millikin University in that city. After two years and hav-

ing exhausted the coursework offered by the biology

department at Millikin, Wilson decided to move to the

U of I, which became a turning point in his life. There,

he met HMS and managed to survive a number of his

courses, including comparative anatomy. During the two

years that led to his graduation, Wilson cemented his in-

terest in zoology and, due to Smith’s influence, decided

to attend graduate school and major in herpetology. Also,

due to Smith’s interest in Mesoamerican amphibians and

reptiles, Wilson was determined to specialize in studying

these creatures, and in 1962 ventured south and never re-

turned to live in the flatlands of the “Great Corn Desert.”

In 1983, Wilson had the opportunity to acknowledge his

gratitude to the Smiths by organizing a symposium on the

Mexican herpetofauna in their honor, which was held in

connection with the annual SSAR meeting in Salt Lake

City, Utah. Although much of Wilson’s overall work has

focused on the Honduran herpetofauna, this special issue

on the Mexican herpetofauna provided him with an op-

portunity to reawaken his love for the country where his

fieldwork outside the US began in 1966, and to again ac-

knowledge his debt to Dr. Hobart Muir Smith, one of the

most important people in the history of herpetology. As

Wilson stated in a tribute to HMS on his centenary pub-

lished last year in Herpetological Review, “I know I am

only one of many people who are indebted to Dr. Smith

in ways small and large. For me, however, his influence

determined the direction of my career and, in a significant

way, the nature of the contributions I have made to our

field.”

Acknowledgments. — The authors of the papers com-

prising the Special Mexico Issue are very grateful to Sally

Nadvornik, who kindly supplied the photographs we used

of her father, Hobart M. Smith, and Uriel Hemandez-Sali-

nas, who helpfully provided the image we used of Aurelio

Ramfrez-Bautista. Louis Porras provided the photographs

/

of Roger Conant. The image of Miguel Alvarez del Toro

was taken from the 3 rd edition of his book, Los Reptiles

de Chiapas.

amphibian-reptile-conservation.org

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June 2013 I Volume 7 | Number 1 | e64

Xenosaurus tzacualtipantecus. The Zacualtipan knob-scaled lizard is endemic to the Sierra Madre Oriental of eastern Mexico.

This medium-large lizard (female holotype measures 188 mm in total length) is known only from the vicinity of the type locality

in eastern Hidalgo, at an elevation of 1,900 m in pine-oak forest, and a nearby locality at 2,000 m in northern Veracruz (Woolrich-

Pina and Smith 2012). Xenosaurus tzacualtipantecus is thought to belong to the northern clade of the genus, which also contains X.

newmanorum and X. platyceps (Bhullar 2011). As with its congeners, X. tzacualtipantecus is an inhabitant of crevices in limestone

rocks. This species consumes beetles and lepidopteran larvae and gives birth to living young. The habitat of this lizard in the vicinity

of the type locality is being deforested, and people in nearby towns have created an open garbage dump in this area. We determined

its EVS as 17, in the middle of the high vulnerability category (see text for explanation), and its status by the IUCN and SEMAR-

NAT presently are undetermined. This newly described endemic species is one of nine known species in the monogeneric family

Xenosauridae, which is endemic to northern Mesoamerica (Mexico from Tamaulipas to Chiapas and into the montane portions of

Alta Verapaz, Guatemala). All but one of these nine species is endemic to Mexico. Photo by Christian Berriozabal-Islas.

amphibian-reptile-conservation.org

01

June 2013 I Volume 7 | Number 1 | e61

mons Attribution-NonCommercial-NoDerivs 3.0 Unported License, which permits unrestricted use for non-com-

mercial and education purposes only provided the original author and source are credited.

Amphibian & Reptile Conservation 7(1): 1-47.

A conservation reassessment of the reptiles of Mexico

based on the EVS measure

^arry David Wilson, 2 Vicente Mata-Silva, and 3 Jerry D. Johnson

1 Centro Zamomno de Biodiversidad, Escuela Agricola Panamericana Zamorano, Departamento de Francisco Morazdn, HONDURAS 2 3 Depart-

ment of Biological Sciences, The University of Texas at El Paso, El Paso, Texas 79968-0500, USA

Abstract. — Mexico is the country with the most significant herpetofaunal diversity and endemism

in Mesoamerica. Anthropogenic threats to Mexico’s reptiles are growing exponentially, commensu-

rate with the rate of human population growth and unsustainable resource use. In a broad-based

multi-authored book published in 2010 ( Conservation of Mesoamerican Amphibians and Reptiles ;

CMAR), conservation assessment results differed widely from those compiled in 2005 by IUCN for

a segment of the Mexican reptile fauna. In light of this disparity, we reassessed the conservation

status of reptiles in Mexico by using the Environmental Vulnerability Score (EVS), a measure previ-

ously used in certain Central American countries that we revised for use in Mexico. We updated the

total number of species for the Mexican reptile fauna from that reported in CMAR, which brought

the new number to 849 (three crocodilians, 48 turtles, and 798 squamates). The 2005 assessment

categorized a small percentage of species in the IUCN threat categories (Critically Endangered, En-

dangered, and Vulnerable), and a large number of species in the category of Least Concern. In view

of the results published in CMAR, we considered their approach overoptimistic and reevaluated the

conservation status of the Mexican reptile fauna based on the EVS measure. Our results show an

inverse (rather than a concordant) relationship between the 2005 IUCN categorizations and the EVS

assessment. In contrast to the 2005 IUCN categorization results, the EVS provided a conservation

assessment consistent with the threats imposed on the Mexican herpetofauna by anthropogenic en-

vironmental degradation. Although we lack corroborative evidence to explain this inconsistency, we

express our preference for use of the EVS measure. Based on the results of our analysis, we provide

eight recommendations and conclusions of fundamental importance to individuals committed to

reversing the trends of biodiversity decline and environmental degradation in the country of Mexico.

Key words. EVS, lizards, snakes, crocodilians, turtles, IUCN categories, IUCN 2005 Mexican Reptile Assessment

Resumen. — Mexico es el pais que contiene la diversidad y endemismo de herpetofauna mas signifi-

cative en Mesoamerica. Las amenazas antropogenicas a los reptiles de Mexico crecen exponencial-

mente acorde con la tasa de crecimiento de la poblacion humana y el uso insostenible de los recur-

sos. Un libro publicado por varios autores en 2010 ( Conservation of Mesoamerican Amphibians and

Reptiles; CMAR) produjo resultados sobre conservacion ampliamente contrarios a los resultados

de una evaluacion de un segmento de los reptiles mexicanos conducida en 2005 por la UICN. A la

luz de esta disparidad, se realizo una nueva evaluacion del estado de conservacion de los reptiles

mexicanos utilizando una medida llamada el Calculo de Vulnerabilidad Ambiental (EVS), revisado

para su uso en Mexico. Se actualizo el numero de especies de reptiles mexicanos mas alia del es-

tudio de CMAR, por lo que el numero total de especies se incremento a 849 (tres cocodrilidos, 48

tortugas, y 798 lagartijas y serpientes). La evaluacion de 2005 de la UICN clasifico una proporcion

inesperadamente pequena de especies en las categories para especies amenazadas (En Peligro

Critico, En Peligro, y Vulnerable) y un porcentaje respectivamente grande en la categoria de Preo-

cupacion Menor. En vista de los resultados publicados en CMAR, consideramos que los resultados

de este enfoque son demasiado optimistas, y reevaluamos el estado de conservacion de todos los

reptiles mexicanos basandonos en la medida de EVS. Nuestros resultados muestran una relacion

inversa (mas que concordante) entre las categorizaciones de la UICN 2005 y EVS. Contrario a los

resultados de las categorizaciones de la UICN 2005, la medida de EVS proporciono una evaluacion

para la conservacion de reptiles mexicanos que es coherente con las amenazas impuestas por la

degradacion antropogenica del medio ambiente. No tenemos la evidencia necesaria para propor-

cionar una explicacion para esta inconsistencia, pero expresamos las razones de nuestra prefer-

ence por el uso de los resultados del EVS. A la luz de los resultados de nuestro analisis, hemos

Correspondence. Emails: 'bufodoc@aol.com (Corresponding author), 2 vmata@ utep.edu, 3 jjohnson@ utep.edu

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June 2013 I Volume 7 | Number 1 | e61

Wilson et al.

construido ocho recomendaciones y conclusiones de importancia fundamental para las personas

comprometidas en revertir las tendencias asociadas con la perdida de biodiversidad y la degra-

dation del medio ambiente.

Palabras claves. EVS, lagartijas, culebras, cocodrflidos, tortugas, categories de UICN, 2005 UICN valoracion de

reptiles mexicanos

Citation: Wilson LD, Mata-Silva V, Johnson JD. 2013. A conservation reassessment of the reptiles of Mexico based on the EVS measure. Amphibian &

Reptile Conservation 7(1 ): 1-47 (e61 ).

The history of civilization is a history of human beings as

they become increasingly knowledgeable about biologi-

cal diversity.

Beattie and Ehrlich 2004: 1.

Introduction

From a herpetofaunal standpoint, Mexico is the most

significant center of diversity in the biodiversity hotspot

of Mesoamerica (Mexico and Central America; sensu

Wilson and Johnson [2010]). Of the 1,879 species of

amphibians and reptiles listed by Wilson and Johnson

(2010) for all of Mesoamerica, 1,203 (64.0%) occur in

Mexico; reptiles are especially diverse in this country,

with 830 species (72.3%) of the 1,148 species distributed

throughout Mesoamerica.

Wilson and Johnson (2010) also reported that the

highest level of herpetofaunal endemism in Mesoamerica

is found in Mexico (66.8% for amphibians, 57.2% for

reptiles [60.2% combined]), with the next highest level

in Honduras (36.2% for amphibians, 19.2% for reptiles

[25.3% combined]). The reported level of herpetofaunal

diversity and endemism in Mexico has continued to in-

crease, and below we discuss the changes that have oc-

curred since the publication of Wilson et al. (2010).

Interest in herpetofaunal diversity and endemicity in

Mexico dates back nearly four centuries (Johnson 2009).

Herpetologists, however, only have become aware of the

many threats to the survival of amphibian and reptile

populations in the country relatively recently. The prin-

cipal driver of these threats is human population growth

(Wilson and Johnson 2010), which is well documented as

exponential. “Any quantity that grows by a fixed percent

at regular intervals is said to possess exponential growth”

(www.regentsprep.org). This characteristic predicts that

any population will double in size depending on the

percentage growth rate. Mexico is the 11 th most popu-

lated country in the world (2011 Population Reference

Bureau World Population Data Sheet), with an estimated

mid-2011 total of 114.8 million people. The population

of Mexico is growing at a more rapid rate (1.4% rate of

natural increase) than the global average (1.2%), and at a

1 .4% rate of natural increase this converts to a doubling

time of 50 years (70/1.4 = 50). Thus, by the year 2061

the population of Mexico is projected to reach about 230

amphibian-reptile-conservation.org 03

million, and the population density will increase from 59

to 118/km 2 (2011 PBR World Population Data Sheet).

Given the widely documented threats to biodiversity

posed by human population growth and its consequences

(Chiras 2009; Raven et al. 2011), as well as the increas-

ing reports of amphibian population declines in the late

1980s and the 1990s (Blaustein and Wake 1990; Wake

1991), the concept of a Global Amphibian Assessment

(GAA) originated and was described as “a first attempt

to assess all amphibians against the IUCN Red List Cat-

egories and Criteria” (Stuart et al. 2010). The results of

this assessment were startling, and given broad press

coverage (Conservation International 2004; Stuart et al.

2004). Stuart et al. (2010) reported that of the 5,743 spe-

cies evaluated, 1,856 were globally threatened (32.3%),

i.e., determined to have an IUCN threat status of Criti-

cally Endangered (CR), Endangered (EN), or Vulnerable

(VU). An additional 1,290 (22.5%) were judged as Data

Deficient (DD), i.e., too poorly known for another deter-

minable status. Given the nature of the Data Deficient

category, eventually these species likely will be judged

in one of the threat categories (CR, EN, or VU). Thus,

by adding the Data Deficient species to those determined

as globally threatened, the total comes to 3,146 species

(54.8% of the world’s amphibian fauna known at the

time of the GAA). Our knowledge of the global amphib-

ian fauna has grown since the GAA was conducted, and

a website (AmphibiaWeb) arose in response to the real-

ization that more than one-half of the known amphibian

fauna is threatened globally or too poorly known to con-

duct an evaluation. One of the functions of this website is

to track the increasing number of amphibian species on a

global basis. On 8 April 2013 we accessed this website,

and found the number of amphibian species at 7,116, an

increase of 23.9% over the number reported in Stuart et

al. (2010).

As a partial response to the burgeoning reports of

global amphibian population decline, interest in the con-

servation status of the world’s reptiles began to grow

(Gibbons et al. 2000). Some of this interest was due to

the recognition that reptiles constitute “an integral part

of natural ecosystems and [...] heralds of environmental

quality,” just like amphibians (Gibbons et al. 2000: 653).

Unfortunately, Gibbons et al. (2000: 653) concluded that,

“reptile species are declining on a global scale,” and fur-

ther (p. 662) that, “the declines of many reptile popula-

tions are si mil ar to those experienced by amphibians in

June 2013 I Volume 7 | Number 1 | e61

Conservation reassessment of Mexican reptiles

Dermatemys mawii. The Central American river turtle is known from large river systems in Mexico, from central Veracruz south-

ward into Tabasco and Chiapas and northeastward into southwestern Campeche and southern Quintana Roo, avoiding the northern

portion of the Yucatan Peninsula. In Central America, it occurs in northern Guatemala and most of Belize. The EVS of this single

member of the Mesoamerican endemic family Dermatemyidae has been calculated as 17, placing it in the middle of the high vulner-

ability category, and the IUCN has assessed this turtle as Critically Endangered. This image is of an individual emerging from its

egg, with its egg tooth prominently displayed. The hatching took place at the Zoologico Miguel Alvarez del Toro in Tuxtla Gutier-

rez, Chiapas, as part of a captive breeding program for this highly threatened turtle. The parents of this hatchling came from the

hydrologic system of the Rio Usumacinta and Playas de Catazaja. Photo by Antonio Ramirez Velazquez.

Terrapene mexicana. The endemic Mexican box turtle is distributed from southern Tamaulipas southward to central Veracruz and

westward to southeastern San Luis Potosf. Its EVS has been determined as 19, placing it in the upper portion of the high vulnerabil-

ity category, but this turtle has not been evaluated by IUCN. This individual is from Gomez Farias, Tamaulipas, within the Reserva

de la Biosfera El Cielo. Photo by Eli Garda Padilla.

amphibian-reptile-conservation.org 04 June 2013 | Volume 7 | Number 1 | e61

Wilson et al.

terms of taxonomic breath, geographic scope, and sever-

ity.” They also identified the following significant threats

to reptile populations: habitat loss and degradation, intro-

duced invasive species, environmental pollution, disease

[and parasitism], unsustainable use, and global climate

change. Essentially, these are the same threats identified

by Vitt and Caldwell (2009) in the Conservation Biology

chapter of their textbook Herpetology.

In the closing chapter of Conservation of Mesoameri-

can Amphibians and Reptiles, Wilson and Townsend

(2010: 774-777) provided six detailed and intensely

critical recommendations for the conservation of the

herpetofauna of this region, based on the premise that

“problems created by humans ... are not solved by treat-

ing only their symptoms.” Because of the nature of these

recommendations, we consider it important to note that

the IUCN conducted a conservation assessment of the

Mexican reptiles in 2005, for which the results were made

available in 2007 (see NatureServe Press Release, 12

September 2007 at www.natureserve.org). The contents

of this press release were startling and unexpected, how-

ever, as indicated by its title, “New Assessment of North

American Reptiles Finds Rare Good News,” and contrast

the conclusions of Wilson and Townsend (2010), which

were based on the entire herpetofauna of Mesoamerica.

The principal conclusion of the press release was that “a

newly completed assessment of the conservation status

of North American reptiles shows that most of the group

is faring better than expected, with relatively few spe-

cies at severe risk of extinction.” Wilson and Townsend

(2010: 773) commented, however, that “conserving the

Mesoamerican herpetofauna will be a major challenge

for conservation biologists, in part, because of the large

number of species involved and the considerable number

that are endemic to individual countries, physiographic

regions, and vegetation zones.”

Given the contrast in the conclusions of these two

sources, and because the 2005 Mexican reptile assess-

ment was based on the IUCN categories and criteria

without considering other measures of conservation sta-

tus, herein we undertake an independent reassessment of

the reptile fauna of Mexico based on the Environmen-

tal Vulnerability Score (EVS), a measure developed by

Wilson and McCranie (2004) for use in Honduras, which

was applied to the herpetofauna of certain Central Amer-

ican countries in Wilson et al. (2010), and modified in

this paper for use in Mexico.

The IUCN System of Conservation Status

Categorization

The 2005 Mexican reptile assessment was conducted

using the IUCN system of conservation status categori-

zation. This system is used widely in conservation biol-

ogy and applied globally, and particulars are found at the

IUCN Red List of Threatened Species website (www.

iucnredlist.org). Specifically, the system is elaborated in

amphibian-reptile-conservation.org

the online document entitled “IUCN Red List of Catego-

ries and Criteria” (2010), and consists of nine categories,

identified and briefly defined as follows (p. 9):

Extinct (EX): ‘ ‘A taxon is Extinct when there is no rea-

sonable doubt that the last individual has died.”

Extinct in the Wild (EW): ‘ ‘A taxon is Extinct in the

Wild when it is known only to survive in cultivation,

in captivity or as a naturalized population (or popula-

tions) well outside the past range.”

Critically Endangered (CR): ‘ ‘A taxon is Critically En-

dangered when the best available evidence indicates

that it meets any of the criteria A to E for Critically

Endangered, and it is therefore considered to be fac-

ing an extremely high risk of extinction in the wild.”

Endangered (EN): “A taxon is Endangered when the

best available evidence indicated that it meets any of

the criteria A to E for Endangered, and is therefore

considered to be facing a very high risk of extinction

in the wild.”

Vulnerable (VU): ‘ ‘A taxon is Vulnerable when the best

available evidence indicates that it meets any of the

criteria A to E for Vulnerable, and it is therefore con-

sidered to be facing a high risk of extinction in the

wild.”

Near Threatened (NT): “A taxon is Near Threatened

when it has been evaluated against the criteria but

does not quality for Critically Endangered, Endan-

gered, or Vulnerable now, but is close to qualifying

for or is likely to qualify for a threatened category in

the near future.

Least Concern (LC): “A taxon is Least Concern when

it has been evaluated against the criteria and does not

qualify for Critically Endangered, Endangered, Vul-

nerable or Near Threatened. Widespread and abun-

dant taxa are included in this category.”

Data Deficient (DD): “A taxon is Data Deficient when

there is inadequate information to make a direct, or

indirect, assessment of its risk of extinction based on

its distribution and/or population status.”

Not Evaluated (NE): “A taxon is Not Evaluated when

it is has not yet been evaluated against the criteria.”

As noted in the definition of the Near Threatened catego-

ry, the Critically Endangered, Endangered, and Vulner-

able categories are those with a threat of extinction in the

wild. A lengthy discussion of criteria A to E mentioned

in the definitions above is available in the 2010 IUCN

document.

A Revised EVS for Mexico

In this paper, we revised the design of the EVS for Mex-

ico, which differs from previous schemes in the compo-

nents of geographic distribution and human persecution.

Initially, the EVS was designed for use in instances

where the details of a species’ population status (upon

June 2013 I Volume 7 | Number 1 | e61

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Conservation reassessment of Mexican reptiles

Trachemys gaigeae. The Big Bend slider is distributed along the Rio Grande Valley in south-central New Mexico and Texas, as well

as in the Rio Conchos system in Chihuahua. Its EVS has been calculated as 18, placing it in the upper portion of the high vulner-

ability category, and the IUCN has assessed this turtle as Vulnerable. This individual is from the Rio Grande about 184 straight kilo-

meters SE of Ciudad Juarez, Chihuahua. Although the picture was taken on the US side (about 44 km SSW of Van Horn, Hudspeth

County, Texas), it was originally in the water. Photo by Vicente Mata-Silva.

Kinosternon oaxacae. The endemic Oaxaca mud turtle occurs in southern Oaxaca and adjacent eastern Guerrero. Its EVS has been

estimated as 15, placing it in the lower portion of the high vulnerability category, and the IUCN considers this kinosternid as Data

Deficient. This individual was found in riparian vegetation along the edge of a pond in La Soledad, Tututepec, Oaxaca. Photo by

Vicente Mata-Silva.

amphibian-reptile-conservation.org 06 June 2013 | Volume 7 | Number 1 | e61

Wilson et al.

which many of the criteria for the IUCN status catego-

rizations depend) are not available, so as to estimate its

susceptibility to future environmental threats. In this

regard, the EVS usually can be calculated as soon as a

species is described, as it depends on information gen-

erally available when the species is discovered. Use of

the EVS, therefore, does not depend on population as-

sessments, which often are costly and time consuming.

Nonetheless, its use does not preclude the implementa-

tion of other measures for assessing the conservation sta-

tus of a species, when these measures can be employed.

After all, conservation assessment measures are only a

guide for designing conservation strategies, and consti-

tute an initial step in our effort to protect wildlife.

The version of the EVS algorithm we developed for

use in Mexico consists of three scales, for which the val-

ues are added to produce the Environmental Vulnerabil-

ity Score. The first scale deals with geographic distribu-

tion, as follows:

1 = distribution broadly represented both inside

and outside Mexico (large portions of range are

both inside and outside Mexico)

2 = distribution prevalent inside Mexico, but

limited outside Mexico (most of range is inside

Mexico)

3 = distribution limited inside Mexico, but preva-

lent outside Mexico (most of range is outside

Mexico)

4 = distribution limited both inside and outside

Mexico (most of range is marginal to areas

near border of Mexico and the United States or

Central America)

5 = distribution only within Mexico, but not re-

stricted to vicinity of type locality

6 = distribution limited to Mexico in the vicinity of

type locality

The second scale deals with ecological distribution

based on the number of vegetation formations occupied,

as follows:

1 = occurs in eight or more formations

2 = occurs in seven formations

3 = occurs in six formations

4 = occurs in five formations

5 = occurs in four formations

6 = occurs in three formations

7 = occurs in two formations

8 = occurs in one formation

The third scale relates to the degree of human persecution

(a different measure is used for amphibians), as follows:

1 = fossorial, usually escape human notice

2 = semifossorial, or nocturnal arboreal or aquatic,

nonvenomous and usually non-mimicking,

sometimes escape human notice

3 = terrestrial and/or arboreal or aquatic, generally

ignored by humans

4 = terrestrial and/or arboreal or aquatic, thought to

be harmful, might be killed on sight

5 = venomous species or mim ics thereof, killed on

sight

6 = commercially or non-commercially exploited

for hides, meat, eggs and/or the pet trade

The score for each of these three components is added to

obtain the Environmental Vulnerability Score, which can

range from 3 to 20. Wilson and McCranie (2004) divided

the range of scores for Honduran reptiles into three cat-

egories of vulnerability to environmental degradation, as

follows: low (3-9); medium (10-13); and high (14-19).

We use a similar categorization here, with the high cat-

egory ranging from 14-20.

For convenience, we utilized the traditional classifica-

tion of reptiles, so as to include turtles and crocodilians,

as well as lizards and snakes (which in a modern context

comprise a group).

Recent Changes to the Mexican Reptile

Fauna

Our knowledge of the composition of the Mexican rep-

tile fauna keeps changing due to the discovery of new

species and the systematic adjustment of certain known

species, which adds or subtracts from the list of taxa that

appeared in Wilson et al. (2010). Since that time, the fol-

lowing nine species have been described:

Gopherus morafkai : Murphy et al. (2011). ZooKeys

113:39-71.

Anolis unilobatus : Kohler and Vesely (2010). Herpe-

tologica 66: 186-207.

Gerrhonotus f cirri: Bryson and Graham (2010). Her-

petologica 66: 92-98.

Scincella kikaapoda : Garcia- Vasquez et al. (2010).

Copeia 2010: 373-381.

Lepidophyma cuicateca: Canseco-Marquez et al.

(2008). Zootaxa 1750: 59-67.

Lepidophyma zongolica : Garcia- Vasquez et al.

(2010). Zootaxa 2657: 47-54.

Xenosaurus tzacualtipantecus : Woolrich-Pina and

Smith (2012). Herpetologica 68: 551-559.

Coniophanes michoacanensis : Flores- Villela and

Smith (2009). Herpetologica 65: 404-412.

Geophis occabus : Pavon-Vazquez et al. (2011). Her-

petologica 67: 332-343.

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Conservation reassessment of Mexican reptiles

Abronia smithi. Smith’s arboreal alligator lizard is endemic to the Sierra Madre de Chiapas, in the southeastern portion of this

state. Its EVS has been determined as 17, placing it in the middle of the high vulnerability category; the IUCN, however, lists this

lizard as of Least Concern. This individual was found in cloud forest in the Reserva de la Biosfera El Triunfo, Chiapas. Photo by

Eli Garcia- Pad ilia.

amphibian-reptile-conservation.org 08 June 2013 | Volume 7 | Number 1 | e61

Wilson et al.

The following 1 8 taxa either have been resurrected from

the synonymy of other taxa or placed in the synonymy of

other taxa, and thus also change the number of species in

the CMAR list:

Phyllodactylus nocticolus : Blair et al. (2009). Zoo-

taxa 2027 : 28-42. Resurrected as a distinct species

from P. xanti.

Sceloporus albiventris : Lemos-Espinal et al. (2004).

Bulletin of the Chicago Herpetological Society 39:

164-168. Resurrected as a distinct species from S.

horridus.

Sceloporus bimaculatus : Leache and Mulcahy (2007).

Molecular Ecology 16: 5216-5233. Returned to

the synonymy of S. magister.

Plestiodon bilineatus : Feria-Ortiz et al. (2011). Her-

petological Monographs 25: 25-51. Elevated to

full species from P brevirostris.

Plestiodon dicei: Feria-Ortiz et al. (2011). Herpeto-

logical Monographs 25: 25-51. Elevated to full

species from P. brevirostris.

Plestiodon indubitus : Feria-Ortiz et al. (2011). Herpe-

tological Monographs 25: 25-51. Elevated to full

species from P. brevirostris.

Plestiodon nietoi: Feria-Ortiz and Garcia- Vazquez

(2012). Zootaxa 3339: 57-68. Elevated to full spe-

cies from P brevirostris.

Aspidoscelis sticto gramma: Walker and Cordes

(2011). Herpetological Review 42: 33-39. Elevat-

ed to full species from A. burti.

Xenosaurus agrenon: Bhullar (2011). Bulletin of the

Museum of Comparative Zoology 160: 65-181. El-

evated to full species from X. grandis.

Xenosaurus rackhami : Bhullar (2011). Bulletin of the

Museum of Comparative Zoology 160: 65-181. El-

evated to full species from X. grandis.

Lampropeltis californiae: Pyron and Burbrink (2009).

Zootaxa 2241: 22-32. Elevated to full species from

L. getula.

Lampropeltis holbrooki: Pyron and Burbrink (2009).

Zootaxa 2241: 22-32. Elevated to full species from

L. getula.

Lampropeltis splendida: Pyron and Burbrink (2009).

Zootaxa 2241: 22-32. Elevated to full species from

L. getula.

Sonora aequalis: Cox et al. (2012). Systematic s and

Biodiversity 10: 93-108. Placed in synonymy of S.

mutabilis.

Coniophanes taylori: Flores-Villela and Smith (2009).

Herpetologica 65: 404-412. Resurrected as a dis-

tinct species from C. piceivittis.

Leptodeira maculata: Daza et al. (2009). Molecular

Phylogenetics and Evolution 53: 653-667. Synon-

ymized with L. cussiliris. The correct name of the

taxon, however, contrary to the decision of Daza et

al. (2009), is L. maculata , inasmuch as this name

was originated by Hallowell in 1861, and thus has

priority. Leptodeira cussiliris, conversely, origi-

nally was named as a subspecies of L. annulata by

Duellman (1958), and thus becomes a junior syn-

onym of L. maculata.

Crotalus ornatus: Anderson and Greenbaum (2012).

Herpetological Monographs 26: 19-57. Resur-

rected as a distinct species from the synonymy of

C. molossus.

Mixcoatlus browni: Jadin et al. (2011). Zoological

Journal of the Linnean Society 163: 943-958. Res-

urrected as a distinct species from M. barbouri.

The following species have undergone status changes,

including some taxa discussed in the addendum to Wil-

son and Johnson (2010):

Anolis beckeri: Kohler (2010). Zootaxa 2354: 1-18.

Resurrected as a distinct species from A. pentapri-

on, which thus no longer occurs in Mexico.

Marisora brachypoda: Hedges and Conn (2012). Zoo-

taxa 3288: 1-244. Generic name originated for a

group of species formerly allocated to Mabuya.

Sphaerodactylus continentalis: McCranie and Hedges

(2012). Zootaxa 3492: 65-76. Resurrection from

synonymy of S. millepunctatus, which thus no lon-

ger occurs in Mexico.

Holcosus chaitzami, H. festivus, and H. undulatus:

Harvey et al. (2012). Zootaxa 3459: 1-156. Gener-

ic name originated for a group of species formerly

allocated to Ameiva.

Lampropeltis knoblochi: Burbrink et al. (2011). Mo-

lecular and Phylogenetic Evolution. 60: 445-454.

Elevated to full species from L. pyromelana, which

thus no longer is considered to occur in Mexico.

Leptodeira cussiliris: Mulcahy. 2007. Biological

Journal of the Linnean Society 92: 483-500. Re-

moved from synonymy of L. annulata, which thus

no longer occurs in Mexico. See Leptodeira macu-

lata entry above.

Leptodeira uribei: Reyes- Velasco and Mulcahy

(2010). Herpetologica 66: 99-110. Removed from

the genus Pseudoleptodeira.

Rhadinella godmani: Myers. 2011. American Muse-

um Novitates 3715: 1-33. Species placed in new

genus from Rhadinaea.

Rhadinella hannsteini: Myers (2011). American Mu-

seum Novitates 3715: 1-33. Species placed in new

genus from Rhadinaea.

Rhadinella kanalchutchan: Myers (2011). American

Museum Novitates 3715: 1-33. Species placed in

new genus from Rhadinaea.

Rhadinella kinkelini: Myers (2011). American Mu-

seum Novitates 3715: 1-33. Species placed in new

genus from Rhadinaea.

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Conservation reassessment of Mexican reptiles

Barisia ciliaris. The widespread Sierra alligator lizard is endemic to Mexico, and is part of a complex that still is undergoing system-

atic study. Its distribution extends along the Sierra Madre Occidental from southern Chihuahua southward through western Durango

and into central Jalisco, and thence into northern Guanajuato and central Queretaro and northward in the Sierra Madre Oriental to

central Nuevo Leon. Its EVS has been calculated as 15, placing it in the lower portion of the high vulnerability category. The IUCN

does not recognize this taxon at the species level, so it has to be considered as Not Evaluated. This individual is from 10. 1 km WNW

of La Congoja, Aguascalientes. Photo by Louis W. Porras.

Lampropeltis mexicana. The endemic Mexican gray-banded kingsnake is distributed from the Sierra Madre Occidental in southern

Durango and the Siena Madre Oriental in extreme southeastern Coahuila southward to northern Guanajuato. Its EVS has been

gauged as 15, placing it in the lower portion of the high vulnerability category, but its IUCN status, however, was determined as of

Least Concern. This individual was found at Banderas de Aguila (N of Coyotes), Durango. Photo by Ed Cassano.

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Wilson et al.

RhadineUa lachrymans : Myers (2011). American Mu-

seum Novitates 3715: 1-33. Species placed in new

genus from Rhadinaea.

RhadineUa posadasi: Myers (2011). American Mu-

seum Novitates 3715: 1-33. Species placed in new

genus from Rhadinaea.

RhadineUa schistosa : Myers (2011). American Mu-

seum Novitates 3715: 1-33. Species placed in new

genus from Rhadinaea.

Sonora aemula: Cox et al. (2012). Systematic s and

Biodiversity 10: 93-108. Generic name changed

from Procinura, which thus becomes a synonym

of Sonora.

Epictia goudotii: Adalsteinsson et al. (2009). Zootaxa

2244: 1-50. Species placed in a new genus from

Leptotyphlops.

Rena boettgeri: Adalsteinsson et al. (2009). Zootaxa

2244: 1-50. Species placed in a new genus from

Leptotyphlops.

Rena bressoni: Adalsteinsson et al. (2009). Zootaxa

2244: 1-50. Species placed in a new genus from

Leptotyphlops.

Rena dissecta: Adalsteinsson et al. (2009). Zootaxa

2244: 1-50. Species placed in a new genus from

Leptotyphlops.

Rena dulcis: Adalsteinsson et al. (2009). Zootaxa

2244: 1-50. Species placed in a new genus from

Leptotyphlops.

Rena humilis: Adalsteinsson et al. (2009). Zootaxa

2244: 1-50. Species placed in a new genus from

Leptotyphlops.

Rena maxima : Adalsteinsson et al. (2009). Zootaxa

2244: 1-50. Species placed in a new genus from

Leptotyphlops.

Rena myopica: Adalsteinsson et al. (2009). Zootaxa

2244: 1-50. Species placed in a new genus from

Leptotyphlops.

Mixcoatlus barbouri: Jadin et al. (2011). Zoological

Journal of the Linnean Society 163: 943-958. New

genus for species removed from Cerrophidion.

Mixcoatlus melanurus: Jadin et al. (2011). Zoological

Journal of the Linnean Society 163: 943-958. New

genus for species removed from Ophryacus.

Results of the 2005 Mexican Reptile

Assessment

The 2005 Mexican Reptile Assessment “was carried out

by zoologists from the non-profit conservation group

NatureServe, working in partnership with reptile ex-

perts from universities, the World Conservation Union

(IUCN), and Conservation International” (NatureServe

Press Release; available at natureserve.org/aboutUS/

PressReleases). This study dealt with “721 species of

lizards and snakes found in Mexico, the United States,

and Canada.” Turtles and crocodilians previously were

assessed. The press release indicated that, “about one

amphibian-reptile-conservation.org

in eight lizards and snakes (84 species) were found to

be threatened with extinction [i.e., judged as Critically

Endangered, Endangered, or Vulnerable], with another

23 species labeled Near Threatened. For 121 lizards and

snakes, the data are insufficient to allow a confident es-

timate of their extinction risk [i.e., judged as Data Defi-

cient], while 493 species (about two-thirds of the total)

are at present relatively secure [i.e., judged as Least Con-

cern].” Thus, the percentages of species that fall into the

standard IUCN assessment categories are as follows: CR,

EN, and VU (11.7); NT (3.2); DD (16.8); and LC (68.4).

Inasmuch as the above results include species that

occur in the United States, Canada, and also those not

evaluated in the survey, we extracted information from

the IUCN Red List website on the ratings provided for

Mexican species alone, and also used the “NE” designa-

tion for species not included in the 2005 assessment. We

list these ratings in Appendix 1 .

Critique of the 2005 Results

Our primary reason for writing this paper is to critique

the results of the Mexican reptile assessment, as reported

in the above press release, and to reassess the conserva-

tion status of these organisms using another conserva-

tion assessment tool. We begin our critique with the data

placed in Appendix 1, which we accessed at the IUCN

Red List website up until 26 May 2012. The taxa listed

in this appendix are current to the present, based on the

changes to the Mexican reptile fauna indicated above.

The data on the IUCN ratings are summarized by family

in Table 1 and discussed below.

We based our examination on the understanding that

the word “critique” does not necessarily imply an unfa-

vorable evaluation of the results of the Mexican reptile

assessment, as conducted using the IUCN categories and

criteria. “Critique,” in the strict sense, implies neither

praise nor censure, and is neutral in context. We under-

stand, however, that the word sometimes is used in a neg-

ative sense, as noted in the 3 rd edition of The American

Heritage Dictionary (1992: 443). Nonetheless, our usage

simply means to render a careful analysis of the results.

Presently, we recognize 849 species of reptiles in

Mexico, including three crocodilians, 48 turtles, 413 liz-

ards and amphisbaenians, and 385 snakes, arrayed in 42

families. This total represents an increase of 19 species

(14 lizards, five snakes) over the totals listed by Wilson

and Johnson (2010). The number and percentage of each

of these 849 species allocated to the IUCN categories,

or not evaluated, are as follows: CR = 9 (1.1%); EN =

38 (4.5%); VU = 45 (5.3%); NT = 26 (3.1%); LC = 424

(49.9%); DD = 118 (13.9%); and NE (not evaluated) =

189 (22.2%). The number and percentage of species col-

lectively allocated to the three threat categories (CR, EN,

and VU) are 92 and 10.8%, respectively. This number is

exceeded by the 118 species placed in the DD category,

and is slightly less than one-half of the 189 species not

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Conservation reassessment of Mexican reptiles

Anolis dollfusianus . The coffee anole is distributed on the Pacific versant from southern Chiapas to western Guatemala. Its EVS has

been determined as 13, placing it at the upper end of the medium vulnerability category, and its IUCN status is undetermined. This

individual was found in cloud forest in Reserva de la Biosfera El Triunfo, Chiapas. Photo by Eli Garcia-Padilla.

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June 2013 I Volume 7 | Number 1 | e61

Table 1 . IUCN Red List categorizations for the Mexican reptile families (including crocodilians, turtles, lizards, and snakes).

Families

Number of

species

IUCN Red List categorizations

Critically

Endangered

Vulnerable

Near

Threatened

Least

Concern

Data

Deficient

Not

Evaluated

Alligatoridae

1

—

1

—

Crocodylidae

2

—

1

—

1

—

Subtotals

3

—

1

—

2

—

Cheloniidae

5

2

1

—

Chelydridae

1

—

1

—

Dermatemydidae

1

—

Dermochelyidae

1

—

Emydidae

15

—

2

4

2

1

4

Geoemydidae

3

—

2

—

1

Kinosternidae

17

—

6

3

2

Testudinidae

3

—

1

—

1

—

1

Trionychidae

2

—

1

—

1

Subtotals

48

4

7

10

4

9

Biporidae

3

—

3

—

Anguidae

48

—

10

4

1

17

10

6

Anniellidae

2

—

1

—

1

—

Corytophanidae

6

—

1

—

5

Crotaphytidae

10

—

1

8

Dactyloidae

50

—

3

2

—

16

12

17

Dibamidae

1

—

1

—

Eublepharidae

7

—

6

—

1

Gymnophthalmi-

dae

1

—

1

Helodermatidae

2

—

1

—

Iguanidae

19

1

—

2

3

—

11

Mabuyidae

1

—

1

Phrynosomatidae

135

1

5

8

6

89

6

20

Phyllodactylidae

15

—

1

10

1

3

Scincidae

23

—

1

—

12

5

Sphaerodactylidae

4

—

4

Sphenomorphidae

6

—

3

—

3

Teiidae

46

—

3

1

35

2

5

Xantusiidae

25

—

1

2

—

6

8

Xenosauridae

9

—

2

1

—

2

1

3

Subtotals

413

2

23

24

12

214

45

93

Boidae

2

—

1

—

1

Colubridae

136

2

3

1

3

77

18

32

Dipsadidae

115

—

3

—

44

38

27

Elapidae

19

—

1

—

13

4

1

Leptotyphlopidae

8

—

5

1

2

Loxocemidae

1

—

1

Natricidae

33

—

2

3

—

20

3

5

Typhlopidae

2

—

2

—

Ungaliophiidae

2

—

1

—

1

Viperidae

59

1

3

4

1

33

4

13

Xenodontidae

8

—

3

1

4

Subtotals

385

3

11

13

4

198

69

87

Totals

849

9

38

45

26

424

118

189

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Conservation reassessment of Mexican reptiles

Mastigodrycis cliftoni. The endemic Clifton’s lizard eater is found along the Pacific versant from extreme southeastern Sonora

southward to Jalisco. Its EVS has been determined as 14, placing it at the lower end of the high vulnerability category, and its IUCN

status has not been assessed. This individual is from El Carrizo, Sinaloa. Photo by Ed Cassano.

Geophis dugesi. The endemic Duges’ earthsnake occurs from extreme southwestern Chihuahua along the length of the Sierra

Madre Occidental southward to Michoacan. Its EVS has been assessed as 13, placing it at the upper end of the medium vulner-

ability category, and its IUCN status has been determined as of Least Concern. This individual was found at El Carrizo, Sinaloa.

Photo by Ed Cassano.

amphibian-reptile-conservation.org 014 June 2013 | Volume 7 | Number 1 | e61

Wilson et al.

evaluated on the website. Thus, of the total of 849 spe-

cies, 307 (36.2%) are categorized either as DD or NE.

As a consequence, only 542 (63.8%) of the total number

are allocated to one of the other five categories (CR, EN,

VU, NT, or LC).

These results provided us with a substantially in-

complete picture of the conservation status of reptiles

in Mexico, which sharply contrasts the picture offered

for Central American reptiles (the other major portion

of Mesoamerica), as recorded in Wilson et al. (2010).

This situation is underscored by the relatively low spe-

cies numbers of Mexican reptiles placed in any of the

three IUCN threat categories. In addition, a substantial

proportion (13.9%) of the Mexican species are assessed

as DD, indicating that insufficient information exists for

the IUCN rating system to be employed. Finally, 189

species (22.3%) are not evaluated, largely because they

also occur in Central America (and in some cases, also

in South America) and will be assessed presumably in

future workshops, which was the case for most of these

species when they were assessed in a Central American

workshop held on May 6-10, 2012; as yet, the results of

that assessment are not available.

Given that only 10.8% of the Mexican species were

allocated to one of the three IUCN threat categories

and that about six in 10 species in the country are en-

demic, we examined the IUCN ratings reported for spe-

cies inhabiting five of the countries in Central America

(see Wilson et al. 2010). For Guatemala, Acevedo et al.

(2010) reported that 56 reptile species (23.0%) of a total

of 244 then recognized were assigned to one of the three

threat categories. Of 237 Honduran reptiles assessed by

Townsend and Wilson (2010), 74 (31.2%) were placed in

one of the threat categories. Sunyer and Kohler (2010)

listed 165 reptile species from Nicaragua, a country with

only three endemic reptiles known at the time, but judged

10 of them (6.1%) as threatened. Of 231 reptile species

assessed by Sasa et al. (2010) for Costa Rica, 36 (15.6%)

were placed in a threat category. Finally, Jaramillo et

al. (2010) placed 22 of 248 Panamanian reptile species

(8.9%) in the threat categories. Collectively, 17% of the

reptile species in these countries were assessed in one of

the three threat categories.

The number of species in Central America placed

into one of the threat categories apparently is related to

the number allocated to the DD category. Although the

DD category is stated explicitly as a non-threat category

(IUCN Red Fist Categories and Criteria 2010), its use

highlights species so poorly known that one of the other

IUCN categories cannot be applied. The percentage of

DD species in the reptile faunas of each of the five Cen-

tral American countries discussed above ranges from 0.9

in Honduras to 40.3 in Panama. Intermediate figures are

as follows: Nicaragua = 1.2; Guatemala = 5.3; Costa Rica

= 34.2. These data apparently indicate that the conser-

vation status of the Costa Rican and Panamanian reptile

faunas are by far more poorly understood than those of

Guatemala, Honduras, and Nicaragua.

The length of time for placing these DD species into

another category is unknown, but a reassessment must

await targeted surveys for the species involved. Given

the uncertainty implied by the use of this category sup-

plemented by that of NE species in Mexico, we believe

there is ample reason to reassess the conservation status

of the Mexican reptiles using the Environmental Vulner-

ability Score (EVS).

EVS for Mexican Reptiles

The EVS provides several advantages for assessing the

conservation status of amphibians and reptiles. First, this

measure can be applied as soon as a species is described,

because the information necessary for its application

generally is known at that point. Second, the calculation

of the EVS is an economical undertaking and does not

require expensive, grant-supported workshops, such as

those held in connection with the Global Reptile Assess-

ment sponsored by the IUCN. Third, the EVS is predic-

tive, because it provides a measure of susceptibility to

anthropogenic pressure, and can pinpoint taxa in need of

immediate attention and continuing scrutiny. Finally, this

measure is simple to calculate and does not “penalize”

species that are poorly known. One disadvantage of the

EVS, however, is that it was not designed for use with

marine species. So, the six species of marine turtles and

two of marine snakes occurring on the shores of Mexico

could not be assessed. Nevertheless, given the increas-

ing rates of human population growth and environmental

deterioration, an important consideration for a given spe-

cies is to have a conservation assessment measure that

can be applied simply, quickly, and economically.

We calculated the EVS for each of the 841 species

of terrestrial reptiles occurring in Mexico (Wilson and

Johnson 2010, and updated herein; see Appendix 1). In

this appendix, we listed the scores alongside the IUCN

categorizations from the 2005 Mexican Reptile Assess-

ment, as available on the IUCN Red List website (www.

iucnredlist.org) and as otherwise determined by us (i.e.,

as NE species).

Theoretically, the EVS can range from 3 to 20. A score

of 3 is indicative of a species that ranges widely both

within and outside of Mexico, occupies eight or more

forest formations, and is fossorial and usually escapes

human notice. Only one such species (the leptotyphlo-

pid snake Epictia goudotii) is found in Mexico. At the

other extreme, a score of 20 relates to a species known

only from the vicinity of the type locality, occupies a

single forest formation, and is exploited commercially or

non-commercially for hides, meat, eggs and/or the pet

trade. Also, only one such species (the trionychid turtle

Ap alone atra ) occurs in Mexico. All of the other scores

fall within the range of 4-19. We summarized the EVS

for reptile species in Mexico by family in Table 2.

June 2013 I Volume 7 | Number 1 | e61

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Conservation reassessment of Mexican reptiles

Rhadinaea laureata. The endemic crowned graceful brownsnake is distributed along the Sierra Madre Occidental from west-central

Durango southward into the Tran verse Volcanic Axis as far as central Michoacan, Morelos, and the Distrito Federal. Its EVS has

been calculated as 12, placing it in the upper portion of the medium vulnerability category, and its IUCN status has been determined

as Least Concern. This individual is from Rancho Las Canoas, Durango. Photo by Louis W. Porras.

Thamnophis mendax. The endemic Tamaulipan montane gartersnake is restricted to a small range in the Sierra Madre Oriental in

southwestern Tamaulipas. Its EVS has been determined as 14, placing it at the lower end of the high vulnerability category, and its

IUCN status has been assessed as Endangered. This individual came from La Gloria, in the Gomez Farias region of Tamaulipas.

Photo by Ed Cassano.

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Wilson et al.

Table 2. Environmental Vulnerability Scores for the Mexican reptile species (including crocodilians, turtles, lizards, and snakes, but excluding the

marine species), arranged by family. Shaded area to the left encompasses low vulnerability scores, and to the right high vulnerability scores.

Families

Number

of

species

Environmental Vulnerability Scores

8

10

11

12

13

14

15

16

17

18

19

20

Alligatoridae

1

Crocodylidae

Subtotals

Subtotal %

33.3

Chelydridae

Dermatemydi-

dae

Emydidae

15

Geoemydidae

Kinosternidae

17

Testudinidae

Trionychidae

Subtotals

42

Subtotal %

2.4

7.1

2.4

7.1

19.0

14.3

9.5

7.1

11.9

14.3

2.4

Bipedidae

Anguidae

48

11

Anniellidae

Corytophani-

dae

Crotaphyti-

dae

10

Dactyloidae

50

15

Dibamidae

Eublephari-

dae

Gymnoph-

thalmidae

Heloderma-

tidae

Iguanidae

19

Mabuyidae

Phrynosoma-

tidae

135

11

18

22

16

23

11

Phyllodactyli-

dae

15

Scincidae

23

Sphaerodac-

tylidae

Sphenomor-

phidae

Teiidae

46

14

Xantusiidae

25

Xenosauridae

Subtotals

413

11

13

14

28

39

49

54

67

78

38

10

Subtotal %

Boidae

0.2

0.7

1.5

2.7

3.1

3.4

6.8

9.4

11.9

13.1

16.2

18.9

9.2

2.4

0.5

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Conservation reassessment of Mexican reptiles

Table 2. Continued.

Colubridae

136

—

4

7

3

6

10

15

8

18

22

14

16

5

—

Dipsadidae

115

—

1

3

8

4

7

6

13

14

13

19

15

6

—

Elapidae

17

—

2

—

2

—

2

3

—

2

3

1

—

Leptotyphlo-

pidae

8

1

—

1

—

2

—

2

—

Loxocemidae

1

Natricidae

33

—

3

1

—

2

3

6

7

4

2

1

—

Typhlopidae

2

1

Ungaliophi-

idae

2

—

1

—

1

—

Viperidae

59

—

1

2

1

3

7

5

6

9

8

5

6

—

Xenodontidae

8

—

1

—

3

1

—

1

—

Subtotals

383

1

7

10

9

19

17

30

25

31

47

52

50

44

24

9

7

—

Subtotal %

—

0.3

1.8

2.6

2.3

5.0

4.4

7.8

6.5

8.1

12.3

13.6

13.1

11.5

6.3

2.3

1.8

—

Totals

841

1

8

13

15

31

30

47

54

71

100

115

123

127

65

24

15

1

Total %

—

0.1

1.0

1.5

1.8

3.7

3.6

5.6

6.4

8.4

11.9

13.7

14.6

15.1

7.7

2.9

1.8

0.1

The range and average EVS for the major reptile

groups are as follows: crocodilians = 13-16 (14.3); tur-

tles = 8-20 (15.3); lizards = 5-19 (13.8); and snakes =

3-19 (12.8). On average, turtles are most susceptible and

snakes least susceptible to environmental degradation,

with lizards and crocodilians falling in between. The av-

erage scores either are at the upper end of the medium

category, in the case of snakes and lizards, or at the lower

end of the high category, in the case of crocodilians and

turtles. The average EVS for all the reptile species is

13.4, a value close to the lower end of the high range of

vulnerability.

Nineteen percent of the turtle species were assigned

an EVS of 14, at the lower end of the high vulnerability

category. For lizards, the respective figures are 18.9%

and 16, about midway through the range for the high vul-

nerability category; for snakes, the values are 13.6% and

14.

The total EVS values generally increase from the low

end of the scale (3) to about midway through the high end

(16), with a single exception (a decrease from 31 to 29

species at scores 8 and 9), then decrease thereafter to the

highest score (20). The peak number of taxa (127) was

assigned an EVS of 16, a score that falls well within the

range of high vulnerability.

Of the 841 total taxa that could be scored, 99 (11.8%)

fall into the low vulnerability category, 272 (32.3%) in

the medium category, and 470 (55.9%) in the high cat-

egory. Thus, more than one-half of the reptile species

in Mexico were judged as having the highest degree of

vulnerability to environmental degradation, and slightly

more than one-tenth of the species the lowest degree.

This increase in absolute and relative numbers from

the low portion, through the medium portion, to the high

portion varies somewhat with the results published for

both the amphibians and reptiles for some Central Amer-

ican countries (see Wilson et al. 2010). Acevedo et al.

(2010) reported 89 species (23.2%) with low scores, 179

(46.7%) with medium scores, and 115 (30.0%) with high

scores for Guatemala. The same trend is seen in Hon-

duras, where Townsend and Wilson (2010) indicated the

following absolute and relative figures in the same order,

again for both amphibians and reptiles: 71 (19.7%); 169

(46.8%); and 121 (33.5%). Comparable figures for the

Panamanian herpetofauna (Jaramillo et al. 2010) are: 143

(33.3%); 165 (38.4%); and 122 (28.4%).

The principal reason that EVS values are relatively

high in Mexico is because of the high level of endemism

and the relatively narrow range of habitat occurrence.

Of the 485 endemic species in Mexico (18 turtles, 264

lizards, 203 snakes), 124 (25.6%) were assigned a geo-

graphic distribution score of 6, signifying that these crea-

tures are known only from the vicinity of their respective

type localities; the remainder of the endemic species (361

[74.4%]) are more broadly distributed within the country

(Appendix 1). Of the 841 terrestrial Mexican reptile spe-

cies, 212 (25.2%) are limited in ecological distribution to

one formation (Appendix 1). These features of geograph-

ic and ecological distribution are of tremendous signifi-

cance for efforts at conserving the immensely important

Mexican reptile fauna.

Comparison of IUCN Categorizations and

EVS Values

Since the IUCN categorizations and EVS values both

measure the degree of environmental threat impinging on

a given species, a certain degree of correlation between

the results of these two measures is expected. Townsend

and Wilson (2010) demonstrated this relationship with

reference to the Honduran herpetofauna, by comparing

the IUCN and EVS values for 362 species of amphibians

and terrestrial reptiles in their table 4. Perusal of the data

in this table indicates, in a general way, that an increase in

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June 2013 I Volume 7 | Number 1 | e61

Wilson et al

Crotalus catalinensis . The endemic Catalina Island rattlesnake is restricted in distribution to Santa Catalina Island in the Gulf of

California. Its EVS has been determined as 19, placing it in the upper portion of the high vulnerability category, and its IUCN status

as Critically Endangered. Photo by Louis W. Porras.

Crotalus stejnegeri. The endemic Sinaloan long-tailed rattlesnake is restricted to a relatively small range in western Mexico, where

it is found in the western portion of the Sierra Madre Occidental in western Durango and southeastern Sinaloa. Its EVS has been

determined as 17, placing it in the middle of the high vulnerability category, and its IUCN status as Vulnerable. This individual came

from Plomosas, Sinaloa. Photo by Louis W. Porras.

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Conservation reassessment of Mexican reptiles

Table 3. Comparison of the Environmental Vulnerability Scores (EVS) and IUCN categorizations for terrestrial Mexican reptiles.

Shaded area on top encompasses the low vulnerability category scores, and at the bottom high vulnerability category scores.

EVS

IUCN categories

Totals

Critically

Endangered

Vulnerable

Near

Threatened

Least

Concern

Data

Deficient

Not

Evaluated

3

—

1

4

—

1

—

1

5

—

3

—

5

8

6

—

5

—

8

13

7

—

5

—

10

15

8

—

20

—

11

31

9

—

1

—

16

—

13

30

10

—

25

1

21

47

11

—

1

36

2

14

54

12

—

1

—

49

4

16

71

13

—

2

5

3

66

5

19

100

14

—

5

6

8

65

15

16

115

15

—

13

11

7

54

25

13

123

16

—

8

3

6

48

38

24

127

17

4

3

11

1

21

14

11

65

18

—

2

—

4

12

4

24

19

2

3

—

4

2

15

20

—

1

Totals

6

36

44

26

422

118

189

841

EVS values is associated with a corresponding increase

in the degree of threat, as measured by the IUCN catego-

rizations. If average EVS values are determined for the

IUCN categories in ascending degrees of threat, the fol-

lowing figures result: LC (206 spp.) =10.5; NT (16 spp.)

= 12.9; VU (18 spp.) = 12.5; EN (64 spp.) = 14.1; CR

(50 spp.) = 15.1; and EX (2 spp.) = 16.0. The broad cor-

respondence between the two measures is evident. Also

of interest is that the average EVS score for the six DD

species listed in the table is 13.7, a figure closest to that

for the EN category (14.1), which suggests that if and

when these species are better known, they likely will be

judged as EN or CR.

In order to assess whether such a correspondence ex-

ists between these two conservation measures for the

Mexican reptiles, we constructed a table (Table 3) simi-

lar to table 4 in Townsend and Wilson (2010). Important

similarities and differences exist between these tables.

The most important similarity is in general appearance,

i.e., an apparent general trend of decreasing EVS values

with a decrease in the degree of threat, as indicated by the

IUCN categorizations. This similarity, however, is more

apparent than real. Our Table 3 deals only with Mexi-

can reptiles, excludes the IUCN category EX (because

presently this category does not apply to any Mexican

species), and includes a NE category that we appended

to the standard set of IUCN categories. Apart from these

obvious differences, however, a closer examination of

the data distribution in our Table 3 reveals more signifi-

cant differences in the overall picture of the conserva-

tion status of the Mexican reptiles when using the IUCN

categorizations, as opposed to the EVS, especially when

viewed against the backdrop of results in Townsend and

Wilson (2010: table 4).

1. Nature of the IUCN categorizations in

Table 3

Unlike the Townsend and Wilson (2010) study, we in-

troduced another category to encompass the Mexican

reptile species that were not evaluated in the 2005 IUCN

study. The category is termed “Not Evaluated” (IUCN

2010) and a large proportion of the species (189 of 841

Mexican terrestrial reptiles [22.5%]) are placed in this

category. Thus, in the 2005 study more than one-fifth of

the species were not placed in one of the standard IUCN

categories, leaving their conservation status as undeter-

mined. In addition, a sizable proportion of species (118

[14.0%]) were placed in the DD category, meaning their

conservation status also remains undetermined. When

the species falling into these two categories are added,

evidently 307 (36.5%) of the 841 Mexican terrestrial rep-

tiles were not placed in one of the IUCN threat assess-

ment categories in the 2005 study. This situation leaves

less than two-thirds of the species as evaluated.

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Wilson et al.

Xantusia sanchezi ■ The endemic Sanchez’s night lizard is known only from extreme southwestern Zacatecas to central Jalisco. This

lizard’s EVS has been assessed as 16, placing it in the middle of the high vulnerability category, but its IUCN status has been deter-

mined as Least Concern. This individual was discovered at Huaxtla, Jalisco. Photo by Daniel Cruz-Sdenz.

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Conservation reassessment of Mexican reptiles

2. Pattern of mean EVS vs. IUCN categoriza-

tions

In order to more precisely determine the relationship be-

tween the IUCN categorizations and the EVS, we calcu-

lated the mean EVS for each of the IUCN columns in Ta-

ble 3, including the NE species and the total species. The

results are as follows: CR (6 spp.) = 17.7 (range 17-19);

EN (36 spp.) = 15.4 (12-19); VU (44 spp.) = 15.3 (10-

19); NT (26 spp.) = 14.6 (11-17); LC (422 spp.) = 13.0

(4-19); DD (118 spp.) = 15.5 (10-19); and NE (189 spp.)

= 12.0 (3-20); and Total (841 spp.) = 13.3 (3-20). The

results of these data show that the mean EVS decreases

from the CR category (17.7) through the EN category

(15.4) to the VU category (15.3), but only slightly be-

tween the EN and VU categories. They also continue to

decrease from the NT category (14.6) to the LC category

(13.0). This pattern of decreasing values was expected.

In addition, as with the Townsend and Wilson (2010)

Honduran study, the mean value for the DD species

(15.5) is closest to that for the EN species (15.4). To us,

this indicates what we generally have suspected about the

DD category, i.e., that the species placed in this category

likely will fall either into the EN or the CR categories

when (and if) their conservation status is better under-

stood. Placing species in this category is of little benefit

to determining their conservation status, however, since

once sequestered with this designation their significance

tends to be downplayed. This situation prevailed once the

results of the 2005 assessment were reported, given that

the 1 1 8 species evaluated as DD were ignored in favor of

the glowing report that emerged in the NatureServe press

release (see above). If the data in Table 3 for the DD spe-

cies is conflated with that for the 86 species placed in one

of the three threat categories, the range of EVS values

represented remains the same as for the threat categories

alone, i.e., 10-19, and the mean becomes 15.5; the same

as that indicated above for the DD species alone and only

one-tenth of a point from the mean score for EN species

(15.4). On the basis of this analysis, we predict that if

a concerted effort to locate and assess the 118 DD spe-

cies were undertaken, that most or all of them would be

shown to qualify for inclusion in one of the three IUCN

threat categories. If that result were obtained, then the

number of Mexican reptile species falling into the IUCN

threat categories would increase from 86 to 204, which

would represent 24.3% of the reptile fauna.

Based on the range and mean of the EVS values, the

pattern for the LC species appears similar to that of the

NE species, as the ranges are 4-19 and 3-20 and the

means are 13.0 and 12.0, respectively. If these score dis-

tributions are conflated, then the EVS range becomes the

broadest possible (3-20) and the mean becomes 12.7,

which lies close to the upper end of the medium vulner-

ability category. While we cannot predict what would

happen to the NE species once they are evaluated (pre-

sumably most species were evaluated during the Central

amphibian-reptile-conservation.org

American reptile assessment of May, 2012), because they

were evaluated mostly by a different group of herpetolo-

gists from those present at the 2005 Mexican assessment,

we suspect that many (if not most) would be judged as

LC species. A more discerning look at both the LC and

NE species might demonstrate that many should be par-

titioned into other IUCN categories, rather than the LC.

Our reasoning is that LC and NE species exhibit a range

of EVS values that extend broadly across low, medium,

and high categories of environmental vulnerability. The

number and percentage of LC species that fall into these

three EVS categories are as follows: Low (range 3-9)

= 50 spp. (11.8%); Medium (10-13) = 176 (41.7); and

High (14-20) = 196 (46.5). For the NE species, the fol-

lowing figures were obtained: Low = 48 (25.8); Medium

= 68 (36.6); and High = 70 (37.6). The percentage values

are reasonably similar to one another, certainly increas-

ing in the same direction from low through medium to

high.

Considering the total number of species, 99 (11.8%)

fall into the low vulnerability category, 272 (32.3%) into

the medium vulnerability category, and 470 (55.9%) into

the high vulnerability category. These results differ sig-

nificantly from those from the 2005 study. If the three

IUCN threat categories can be considered most compa-

rable to the high vulnerability EVS category, then 86 spe-

cies fall into these three threat categories, which is 16.1%

of the total 534 species in the CR, EN, VU, NT, and LC

categories. If the NT category can be compared with the

medium vulnerability EVS category, then 26 species fall

into this IUCN category (4.9% of the 534 species). Fi-

nally, if the LC category is comparable to the low vul-

nerability EVS category, then 422 species (79.0%) fall

into this IUCN category. Clearly, the results of the EVS

analysis are nearly the reverse of those obtained from the

IUCN categorizations discussed above.

Discussion

In the Introduction we indicated that our interest in con-

ducting this study began after the publication of Wilson

et al. (2010), when we compared the data resulting from

that publication with a summary of the results of a 2005

Mexican reptile assessment conducted under the aus-

pices of the IUCN, and later referenced in a 2007 press

release by NatureServe, a supporter of the undertaking.

Our intention was not to critique the IUCN system of

conservation assessment (i.e., the well-known IUCN cat-

egorizations), but rather to critique the results of the 2005

assessment. We based our critique on the use of the En-

vironmental Vulnerability Score (EVS), a measure used

by Wilson and McCranie (2004) and in several Central

American chapters in Wilson et al. (2010).

Since the IUCN assessment system uses a different

set of criteria than the EVS measure, we hypothesized

that the latter could be used to test the results of the for-

mer. On this basis, we reassessed the conservation status

June 2013 I Volume 7 | Number 1 | e61

022

Wilson et al.

of the reptiles of Mexico, including, by our definition of

convenience, crocodilians, turtles, lizards, and snakes,

by determining the EVS value for each terrestrial spe-

cies (since the measure was not designed for use with

marine species). Based on our updating of the species

list in Wilson and Johnson (2010), our species list for

this study consisted of 841 species. We then developed

an EVS measure applicable to Mexico, and employed it

to calculate the scores indicated in Appendix 1 .

Our analysis of the EVS values demonstrated that

when the scores are arranged in low, medium, and high

vulnerability categories, the number and percentage

of species increases markedly from the low category,

through the medium category, to the high category (Ta-

ble 2). When these scores (Table 3) are compared to the

IUCN categorizations documented in Table 1, however,

an inverse correlation essentially exists between the re-

sults obtained from using the two methods. Since both

methods are designed to render conservation status as-

sessments, the results would be expected to corroborate

one another.

We are not in a position to speculate on the reason(s)

for this lack of accord, and simply are offering a reassess-

ment of the conservation status of Mexico’s reptile spe-

cies based on another measure (EVS) that has been used

in a series of studies since it was introduced by Wilson

and McCranie (1992), and later employed by McCranie

and Wilson (2002), Wilson and McCranie (2004), and

several chapters in Wilson et al. (2010). Nonetheless, we

believe our results provide a significantly better assess-

ment of the conservation status Mexico’s reptiles than

those obtained in the 2005 IUCN assessment. We con-

sider our results more consonant with the high degree of

reptile endemism in the country, and the restricted geo-

graphic and ecological ranges of a sizable proportion of

these species. We also believe that our measure is more

predictive, and reflective of impact expected from con-

tinued habitat fragmentation and destruction in the face

of continuing and unregulated human population growth.

Conclusions and Recommendations

Our conclusions and conservation recommendations

draw substantially from those promulgated by Wilson

and Townsend (2010), which were provided for the en-

tire Mesoamerican herpetofauna; thus, we refined them

specifically for the Mexican reptile fauna, as follows:

1. In the introduction we noted the human population

size and density expected for Mexico in half a cen-

tury, and no indication is available to suggest that

this trend will be ameliorated. Nonetheless, although

66% of married women in Mexico (ages 15-49) use

modern methods of contraception, the current fertility

rate (2.3) remains above the replacement level (2.0)

and 29% of the population is below the age of 15, 1%

above the average for Latin America and the Carib-

bean (2011 PRB World Population Data Sheet).

2. Human population growth is not attuned purposefully

to resource availability, and the rate of regeneration

depends on the interaction of such societal factors as

the level of urbanization; in Mexico, the current level

is 78%, and much of it centered in the Distrito Fed-

eral (2011 PRB World Population Data Sheet). This

statistic is comparable to that of the United States

(79%) and Canada (80%), and indicates that 22% of

Mexico’s population lives in rural areas. Given that

the level of imports and exports are about equal (in

2011, imports = 350.8 billion US dollars, exports =

349.7 billion; CIA World Factbook 2012), the urban

population depends on the basic foodstuffs that the

rural population produces. An increase in human pop-

ulation demands greater agricultural production and /

or efficiency, as well as a greater conversion of wild

lands to farmlands. This scenario leads to habitat loss

and degradation, and signals an increase in biodiver-

sity decline.

3. Although the rate of conversion of natural habitats to

agricultural and urban lands varies based on the meth-

ods and assumptions used for garnering this determi-

nation, most estimates generally are in agreement.

The Secretarfa del Medio Ambiente y Recursos Na-

turales (SEMARNAT; Secretariat of Environment and

Natural Resources; semarnat.gob.mx) has attempted

to measure the rate of deforestation from 1978 to

2005, with estimates ranging from about 200,000 to

1.500.000 ha/yr. Most estimates, however, range from

about 200,000 to 400,000 ha/yr. A study conducted

for the years 2000 to 2005 reported an average rate of

260.000 ha/yr. Another source of information (www.

rainforests.mongabay.com) reports that from 1990 to

2010 Mexico lost an average of 274,450 ha (0.39% of

the total 64,802,000 ha of forest in the country), and

during that period lost 7.8% of its forest cover (ca.

5.489.000 ha). No matter the precise figures for for-

est loss, this alarming situation signifies considerable

endangerment for organismic populations, including

those of reptiles. About one-third of Mexico is (or

was) covered by forest, and assuming a constant rate

of loss all forests would be lost in about 256 years

(starting from 1990), or in the year 2246. Forest loss

in Mexico, therefore, contributes significantly to the

global problem of deforestation.

4. As a consequence, no permanent solution to the prob-

lem of biodiversity decline (including herpetofaunal

decline) will be found in Mexico (or elsewhere in the

world) until humans recognize overpopulation as the

major cause of degradation and loss of humankind’s

fellow organisms. Although this problem is beyond

the scope of this investigation, solutions will not be

June 2013 I Volume 7 | Number 1 | e61

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Conservation reassessment of Mexican reptiles

available until humanity begins to realize the origin,

nature, and consequences of the mismatch between

human worldviews and how our planet functions. Wil-

son (1988) labeled this problem “the mismanagement

of the human min d.” Unfortunately, such realignment

is only envisioned by a small cadre of humans, so

crafting provisional solutions to problems like biodi-

versity decline must proceed while realizing the ul-

timate solution is not available, and might never be.

5. Mexico is the headquarters of herpetofaunal diver-

sity and endemism in Mesoamerica, which supports

the conclusions of Ochoa-Ochoa and Flores-Villela

(2006), Wilson and Johnson (2010), and the authors

of four chapters on the Mexican herpetofauna in Wil-

son et al. (2010). Furthermore, field research and sys-

tematic inquiry in Mexico will continue to augment

the levels of diversity and endemicity, which are of

immense conservation significance because reptiles

are significant contributors to the proper functioning

of terrestrial and aquatic ecosystems (Gibbons et al.

2000). From a political and economic perspective,

diversity and endemism are important components

of Mexico’s patrimony, as well as a potential source

of income from ecotourism and related activities. In-

vesting in such income sources should appeal to local

stakeholders, as it provides an incentive for preserv-

ing natural habitats (Wilson 2011).

6. Given that the ultimate solutions to biodiversity de-

cline are unlikely to be implemented in any pertinent

time frame, less effective solutions must be found.

Vitt and Caldwell (2009) discussed a suite of ap-

proaches for preserving and managing threatened

species, including the use of reserves and corridors

to save habitats, undertaking captive management

initiatives, and intentionally releasing individuals to

establish or enlarge populations of target species. Un-

questionably, preserving critical habitat is the most

effective and least costly means of attempting to res-

cue threatened species. Captive management is less

effective, and has been described as a last-ditch effort

to extract a given species from the extinction vortex

(Campbell et al. 2006). Efforts currently are under-

way in segments of the herpetological community to

develop programs for ex situ and in situ captive man-

agement of some of the most seriously threatened her-

petofaunal species, but such efforts will succeed only

if these species can be reproduced in captivity and

reintroduced into their native habitats. In the case of

Mexico, Ochoa-Ochoa, et al. (2011: 2710) comment-

ed that, “given the current speed of land use change,

we cannot expect to save all species from extinction,

and so must decide how to focus limited resources to

prevent the greatest number of extinctions,” and for

amphibians proposed “a simple conservation triage

method that: evaluates the threat status for 145 micro-

endemic Mexican amphibian species; assesses current

potential threat abatement responses derived from

existing policy instruments and social initiatives; and

combines both indicators to provide broad-scale con-

servation strategies that would best suit amphibian

micro-endemic buffered areas (AMBAs) in Mexico.”

These authors concluded, however, that a quarter of

the micro-endemic amphibians “urgently need field-

based verification to confirm their persistence due to

the small percentage of remnant natural vegetation

within the AMBAs, before we may sensibly recom-

mend” a conservation strategy. Their tool also should

apply to Mexican reptiles, and likely would produce

similar results.

7. The preferred method for preserving threatened spe-

cies is to protect habitats by establishing protected

areas, both in the public and private sectors. Habitat

protection allows for a nearly incalculable array of re-

lationships among organisms. Like most countries in

the world, Mexico, has developed a governmentally

established system of protected areas. Fortunately,

studies have identified “critical conservation zones”

(Ceballos et al. 2009), as well as gaps in their cover-

age (Koleff et al. 2009). The five reserves of great-

est conservation importance for reptiles are the Los

Tuxtlas Biosphere Reserve, the islands of the Gulf of

California in the UNESCO World Heritage Site, the

Sierra Gorda Biosphere Reserve, the Tehuacan-Cui-

catlan Biosphere Reserve, and the Chamela-Cuixmala

Biosphere Reserve. Significantly, all of these areas

are part of the UNESCO World Network of Biosphere

Reserves, but attainment of this status does not guar-

antee that these reserves will remain free from anthro-

pogenic damage. Ceballos et al. (2009, citing Dirzo

and Garcia 1992) indicated that although the Los

Tuxtlas is the most important reserve in Mexico for

amphibians and reptiles, a large part of its natural veg-

etation has been lost. This example of deforestation is

only one of many, but led Ceballos et al. (2009: 597)

to conclude (our translation of the original Spanish)

that, “The determination of high risk critical zones has

diverse implications for conservation in Mexico. The

distribution of critical zones in the entire country con-

firms the problem of the loss of biological diversity

is severe at the present time, and everything indicates

it will become yet more serious in future decades.

On the other hand, the precise identification of these

zones is a useful tool to guide political decisions con-

cerning development and conservation in the country,

and to maximize the effects of conservation action.

Clearly, a fundamental linchpin for the national con-

servation strategy is to direct resources and efforts to

protect the high-risk critical zones. Finally, it also is

evident that tools for management of production and

development, such as the land-use planning and en-

vironmental impact, should be reinforced in order to

June 2013 I Volume 7 | Number 1 | e61

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024

Wilson et al.

fully comply with their function to reconcile develop-

ment and conservation.” We fully support this recom-

mendation.

8. Humans have developed an amazing propensity for

living in an unsustainable world. Organisms only can

persist on Earth when they live within their environ-

mental limiting factors, and their strategy is sustain-

ability, i.e., in human terms, living over the long term

within one’s means, a process made allowable by or-

ganic evolution. Homo sapiens is the only extant spe-

cies with the capacity for devising another means for

securing its place on the planet, i.e., a strategy of un-

sustainability over the short term, which eventually is

calculated to fail. Conservation biology exists because

humans have devised this unworkable living strategy.

What success it will have in curbing biodiversity loss

remains to be seen.

Acknowledgments. — We are grateful to the follow-

ing individuals for improving the quality of this contri-

bution: Irene Goyenechea, Pablo Lavm-Murcio, Julio

Lemos-Espinal, and Aurelio Ramirez-Bautista. We are

especially thankful to Louis W. Porras, who applied his

remarkable editorial skills to our work.

Literature Cited

Acevedo M, Wilson LD, Cano EB, Vasquez-Almazan C.

2010. Diversity and conservation status of the Gua-

temalan herpetofauna. Pp. 406-435 In: Conservation

of Mesoamerican Amphibians and Reptiles. Editors,

Wilson LD, Townsend JH, Johnson JD. Eagle Moun-

tain Publishing, LC, Eagle Mountain, Utah, USA.

Adalsteinsson SA, Branch WR, Trape S, Vitt LJ, Hedges

SB. 2009. Molecular phylogeny, classification, and

biogeography of snakes of the family Leptotyphlopi-

dae (Reptilia, Squamata). Zootaxa 2244: 1-50.

American Heritage Dictionary (3 rd edition). 1993. Hough-

ton Mifflin Company, Boston, Massachusetts, USA.

Anderson CG, Greenbaum E. 2012. Phylogeography of

northern populations of the black-tailed rattlesnake

(Crotalus molossus Baird and Girard, 1853), with the

revalidation of C. ornatus Hallowell, 1854. Herpeto-

logical Monographs 26: 19-57.

Beattie A., Ehrlich PR. 2004. Wild Solutions: How Bio-

diversity is Money in the Bank (2 nd edition). Yale Uni-

versity Press, New Haven, Connecticut, USA.

Bhullar, B-AS. 2011. The power and utility of morpho-

logical characters in systematics: a fully resolved

phylogeny of Xenosaurus and its fossil relatives

(Squamata: Anguimorpha ). Bulletin of the Museum of

Comparative Zoology 160: 65-181.

Blair C, Mendez de la Cruz FR, Ngo A, Lindell J, Lath-

rop A, Robert WM. 2009. Molecular phylogenetics

and taxonomy of leaf-toed geckos (Phyllodactylidae:

Phyllodactylus ) inhabiting the peninsula of Baja Cali-

fornia. Zootaxa 2027: 28-42.

Blaustein AR, Wake DB. 1990. Declining amphibian

populations: A global phenomenon? Trends in Ecol-

ogy and Evolution 5: 203-204.

Bryson Jr. RW, Graham MR. 2010. Anew alligator lizard

from northeastern Mexico. Herpetologica 66: 92-98.

Burbrink FT, Yao H, Ingrasci M, Bryson Jr RW, Guiher

TJ, Ruane S. 2011. Speciation at the Mogollon Rim

in the Arizona mountain kingsnake ( Lampropeltis py-

romelana). Molecular and Phylogenetic Evolution 60:

445_454.

Campbell NA, Reese JB, Taylor MR, Simon EJ. 2006.

Biology: Concepts and Connections (5 th edition).

Pearson Benjamin Cummings, New York, New York,

USA.

Canseco-Marquez L, Gutierrez-Mayen G, Mendoza-

Hernandez AA. 2008. A new species of night-lizard

of the genus Lepidophyma (Squamata: Xantusiidae)

from the Cuicatlan Valley, Oaxaca, Mexico. Zootaxa

1750: 59-67.

Ceballos G, Diaz Pardo E, Espinosa H, Flores-Villela

O, Garcia A, Martinez L, Martinez Meyer E, Navarro

A, Ochoa L, Salazar I, Santos Barrera G. 2009. Zo-

nas criticas y de alto riesgo para la conservacion de

la biodiversidad de Mexico. Pp. 575-600 In: Capital

natural de Mexico (Volume II). Estado de conserva-

cion y tendencias de cambio. CONABIO, Mexico,

DF, Mexico.

Central Intelligence Agency. 2012. The World Factbook.

United States Government Printing Office, Washing-

ton, DC, USA.

Chiras DD. 2009. Environmental Science (8 th edition).

Jones and Bartlett Publishers, Burlington, Massachu-

setts, USA.

Conservation International. 2004. Amphibians in dramatic

decline; study finds nearly one-third of species threat-

ened with extinction. ScienceDaily. Available: www.

sciencedaily.com/releases/2004/ 10/041015103700.

htm [Accessed: 21 May 2012].

Cox CL, Dadis Rabosky AR, Reyes- Velasco J, Ponce-

Campos P, Smith EN, Flores-Villela O, Campbell

JA. 2012. Molecular systematics of the genus Sonora

(Squamata: Colubridae) in central and western Mexi-

co. Systematics and Biodiversity 10: 93-108.

Daza JM, Smith EN, Paez VP, Parkinson CL. 2009.

Complex evolution in the Neotropics: The origin and

diversification of the widespread genus Leptodeira

(Serpentes: Colubridae). Molecular Phylogenetics

and Evolution 53: 653-667.

Dirzo R, Garcia MC. 1992. Rates of deforestation in Los

Tuxtlas, a Neotropical area in southeast Mexico. Con-

servation Biology 6: 84-90.

Duellman WE. 1958. A monographic study of the colu-

brid snake genus Leptodeira. Bulletin of the American

Museum of Natural History 114: 1-152.

June 2013 I Volume 7 | Number 1 | e61

amphibian-reptile-conservation.org

025

Conservation reassessment of Mexican reptiles

Feria-Ortiz MN, Manrfques-Moran NL, Nieto-Montes

de Oca A. 2011. Species limits based on mtDNA and

morphological data in the polytypic species Pleist-

odon brevirostris (Squamata: Scincidae). Herpeto-

logical Monographs 25: 25-51.

Feria-Ortiz M, Garcia- Vazquez. 2012. A new species of

Plestiodon (Squamata: Scincidae) from Sierra Madre

del Sur of Guerrero, Mexico. Zootaxa 3339: 57-68.

Flores-Villela O, Smith EN. 2009. A new species of Co-

niophanes (Squamata: Colubridae), from the coast of

Michoacan, Mexico. Herpetologica 65: 404-412.

Garcia- Vasquez UO, Canseco-Marquez L, Aguilar-

Lopez JL. 2010. A new species of night lizard of the

genus Lepidophyma (Squamata: Xantusiidae) from

southern Puebla, Mexico. Zootaxa 2657: 47-54.

Garcia- Vasquez UO, Canseco-Marquez L, Nieto-Montes

de Oca A. 2010. A new species of Scincella (Squa-

mata: Scincidae) from the Cuatra Cienegas Basin,

Coahuila, Mexico. Copeia 2010: 373-381.

Gibbons, JW, Scott DE, Ryan TJ, Buhlmann KA, Tu-

berville TD, Metts BS, Greene JL, Mills T, Leiden

Y, Poppy S, Winne CT. 2000. The global decline of

reptiles, deja vu amphibians. BioScience 50: 653-666.

Hallowell E. 1861 (1860). Report upon the Reptilia of

the North Pacific Exploring Expedition, under com-

mand of Capt. John Rogers [sic], U.S.N. Proceedings

of the Academy of Natural Sciences of Philadelphia

12: 480-510.

Harvey, MB, Ugueto GN, Gutberlet Jr. RL. 2012. Re-

view of teiid morphology with a revised taxonomy

and phylogeny of the Teiidae ( Lepidosauria : Squa-

mata). Zootaxa 3459: 1-156.

Hedges SB, Conn CE. 2012. Anew skink fauna from Ca-

ribbean islands (Squamata, Mabuyidae, Mabuyinae).

Zootaxa 3288: 1-244.

IUCN Red List Categories and Criteria. 2010. Available:

www.iucnredlist.org [Accessed: 22 July 2011].

Jadin R, Smith EN, Campbell JA. 2011. Unravelling a

tangle of Mexican serpents: A systematic revision of

highland pitvipers. Zoological Journal of the Linnean

Society 163: 943-958.

Jaramillo C, Wilson LD, Ibanez R, Jaramillo F. 2010.

The herpetofauna of Panama: Distribution and con-

servation status. Pp. 604-673 In: Conservation ofMe-

soamerican Amphibians and Reptiles. Editors, Wilson

LD, Townsend JH, Johnson JD. Eagle Mountain Pub-

lishing, LC, Eagle Mountain, Utah, USA.

Johnson JD. 2009. Prologue. Pp. xvii-xx In: Herpetofau-

na del Valle de Mexico: Diversidad y conservacion.

Ramfrez-Bautista A, Hernandez-Salinas U, Garcfa-

Vazquez UO, Leyte-Manrique A, Canseco-Marquez

L. Universidad Autonoma del Estado de Hidalgo,

CONABIO, Tlalpan, Mexico, DF, Mexico.

Kohler G. 2010. A revision of the Central American spe-

cies related to Anolis pentaprion with the resurrection

of A. beckeri and the description of a new species

(Squamata: Polychrotidae). Zootaxa 2354: 1-18.

Kohler G, Vesely M. 2010. A revision of the Anolis seri-

ceus complex with the resurrection of A. wellbornae

and the description of a new species (Squamata: Poly-

chrotidae). Herpetologica 66: 186-207.

Koleff P, Tambutti M, March IJ, Esquivel R, Cantu C,

Lira-Noriega A et al. 2009. Identification de priori-

dades y analisis de vatios y omisiones en la conser-

vacion de la biodiversidad de Mexico. Pp. 651-718

In: Capital Natural de Mexico (Volume II). Estado

de conservacion y tendencias de cambio. CONABIO,

Mexico, DF, Mexico.

Leache AD, Mulcahy DG. 2007. Phylogeny, divergence

times and species limits of spiny lizards ( Sceloporus

magister species group) in western North American

deserts and Baja California. Molecular Ecology 16:

5216-5233.

Lemos-Espinal JA, Chiszar D, Smith HM, Woolrich-

Pina G. 2004. Selected records of 2003 lizards from

Chihuahua and Sonora, Mexico. Bulletin of the Chi-

cago Herpetological Society 39: 164-168.

McCranie JR, Hedges SB. 2012. Two new species of

geckos from Honduras and resurrection of Sphaero-

dactylus continentalis Werner from the synonymy of

Sphaerodactylus millepunctatus Hallowell (Reptilia,

Squamata, Gekkonoidea, Sphaerodactylidae). Zoo-

taxa 3492: 65-76.

McCranie JR, Wilson LD. 2002. The Amphibians of

Honduras. Society for the Study of Amphibians and

Reptiles, Contributions in Herpetology, Number 19.

Ithaca, New York, USA.

Mulcahy DG. 2007. Molecular systematics of Neotropi-

cal cat-eyed snakes: A test of the monophyly of Lep-

todeirini (Colubridae: Dipsadinae) with implications

for character evolution and biogeography. Biological

Journal of the Linnean Society 92: 483-500.

Murphy RW, Berry KH, Edwards T, Leviton AE, Lathrop

A, Riedle JD. 2011. The dazed and confused identity

of Agassiz’s land tortoise, Gopherus agassizii (Testu-

dines, Testudinidae) with the description of a new spe-

cies, and its consequences for conservation. ZooKeys

113:39-71.

Myers CW. 201 1 . A new genus and new tribe for Enicog-

nathus melanauchen Jan, 1863, a neglected South

American snake (Colubridae, Xenodontinae), with

taxonomic notes on some Dipsadinae. American Mu-

seum Novitates 3715: 1-33.

NatureServe Press Release. 2007. New assessment of

North American reptiles finds rare good news. Avail-

able: www.natureserve.org [Accessed: 21 May 2012].

Ochoa-Ochoa LM, Bezaury-Creel JE, Vazquez L-B,

Flores-Villela O. 2011. Choosing the survivors? A

GIS-based triage support tool for micro-endemics: ap-

plication to data for Mexican amphibians. Biological

Conservation 144: 2710-2718.

Ochoa-Ochoa LM, Flores-Villela OA. 2006. Areas de

amphibian-reptile-conservation.org

026

June 2013 I Volume 7 | Number 1 | e61

Wilson et al.

Diversidad y Endemismo de la Herpetofauna Mexi-

cana. Universidad Nacional Autonoma de Mexico-

Comision Nacional para el Conocimiento y Uso de la

Biodiversidad, Mexico, DF, Mexico.

Pavon-Vazquez CJ, Garcia- Vazquez UO, Blancas-

Hernandez JC, Nieto-Montes A. 2011. A new species

of the Geophis sieboldi group (Squamata: Colubridae)

exhibiting color pattern polymorphism from Guerre-

ro, Mexico. Herpetologica 67: 332-343.

Population Reference Bureau. 2011. World Population

Data Sheet. Available: www.prb.org [Accessed: 27

January 2012].

Pyron RA, Burbrink FT. 2009. Systematics of the com-

mon kingsnake ( Lampropeltis getula; Serpentes: Col-

ubridae) and the burden of heritage in taxonomy. Zoo-

taxa 2241: 22-32.

Raven PH, Hassenzahl DM, Berg LR. 2009. Environ-

ment (8 th edition). John Wiley & Sons, Inc. Hoboken,

New Jersey, USA.

Reyes- Velasco J, Mulcahy DG. 2010. Additional taxo-

nomic remarks on the genus Pseudoleptodeira (Ser-

pentes: Colubridae) and the phylogenetic placement

of “P. uribeiC Herpetologica 66: 99-110.

Sasa M, Chaves G, Porras LW. 2010. The Costa Rican

herpetofauna: conservation status and future perspec-

tives. Pp. 510-603 In: Conservation of Mesoameri-

can Amphibians and Reptiles. Editors, Wilson LD,

Townsend JH, Johnson JD. Eagle Mountain Publish-

ing, LC, Eagle Mountain, Utah, USA.

Stuart SN, Chanson JS, Cox NA, Young BE, Rodrigues

ASL, Fischman DL, Waller RW. 2004. Status and

trends of amphibian declines and extinctions world-

wide. Science 306(5702): 1783-1786.

Stuart SN, Chanson JS, Cox NA, Young BE. 2010. The

global decline of amphibians: Current trends and fu-

ture prospects. Pp. 2-15 In: Conservation of Meso-

american Amphibians and Reptiles. Editors, Wilson

LD, Townsend JH, Johnson JD. Eagle Mountain Pub-

lishing, LC, Eagle Mountain, Utah, USA.

Sunyer J, Kohler G. 2010. Conservation status of the

herpetofauna of Nicaragua. Pp. 488-509 In: Conser-

vation of Mesoamerican Amphibians and Reptiles.

Editors, Wilson LD, Townsend JH, Johnson JD. Eagle

Mountain Publishing, LC, Eagle Mountain, Utah,

USA.

Townsend JH, Wilson LD. 2010. Conservation of the

Honduran herpetofauna: issues and imperatives. Pp.

460-487 In: Conservation of Mesoamerican Amphib-

ians and Reptiles. Editors, Wilson LD, Townsend JH,

Johnson JD. Eagle Mountain Publishing, LC, Eagle

Mountain, Utah, USA.

Vitt LJ, Caldwell JP. 2009. Herpetology (3 rd edition).

Academic Press, Burlington, Maine, USA.

Wake DB. 1991. Declining amphibian populations. Sci-

ence 253(5022): 860.

Walker JM, Cordes JE. 2011. Taxonomic implications

of color pattern and meristic variation in Aspidoscelis

burti burti, a Mexican whiptail lizard. Herpetological

Review 42: 33-39.

Wilson EO (Editor). 1988. Biodiversity. National Acad-

emy Press, Washington, DC, USA.

Wilson LD. 2011. Imperatives and opportunities: refor-

mation of herpetology in the age of amphibian de-

cline. Herpetological Review 42: 146-150.

Wilson LD, Johnson JD. 2010. Distributional patterns

of the herpetofauna of Mesoamerica, a biodiversity

hotspot. Pp. 30-235 In: Conservation of Mesoameri-

can Amphibians and Reptiles. Editors, Wilson LD,

Townsend JH, Johnson JD. Eagle Mountain Publish-

ing, LC, Eagle Mountain, Utah, USA.

Wilson LD, McCranie JR. 1992. Status of amphibian

populations in Honduras. Unpublished Report to the

Task Force on Declining Amphibian Population, 15

August 1992. 14 p.

Wilson LD, McCranie JR. 2004. The conservation status

of the herpetofauna of Honduras. Amphibian & Rep-

tile Conservation 3: 6-33.

Wilson LD, Townsend JH. 2010. The herpetofauna of

Mesoamerica: biodiversity significance, conservation

status, and future challenges. Pp. 760-812 In: Con-

servation of Mesoamerican Amph ibians and Reptiles.

Editors, Wilson LD, Townsend JH, Johnson JD. Eagle

Mountain Publishing, LC, Eagle Mountain, Utah,

USA.

Wilson LD, Townsend JH, Johnson JD. 2010. Conserva-

tion of Mesoamerican Amphibians and Reptiles. Ea-

gle Mountain Publishing, LC, Eagle Mountain, Utah,

USA.

Woolrich-Pina, GA, Smith GR. 2012. A new species of

Xenosaurus from the Sierra Madre Oriental, Mexico.

Herpetologica 68: 551-559.

World Wildlife Fund. 2012. Living Planet Report 2012.

WWF International, Gland, Switzerland.

Received: 18 Feb 2013

Accepted: 24 April 2013

Published: 09 June 2013

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Conservation reassessment of Mexican reptiles

Larry David Wilson is a herpetologist with lengthy experience in Mesoamerica, totaling six collective years

(combined over the past 47). Larry is the senior editor of the recently published Conservation ofMeso-

american Amphibians and Reptiles and a co-author of seven of its chapters. He retired after 35 years of

service as Professor of Biology at Miami-Dade College in Miami, Florida. Larry is the author or co-author

of more than 290 peer-reviewed papers and books on herpetology, including the 2004 Amphibian & Rep-

tile Conservation paper entitled “The conservation status of the herpetofauna of Honduras.” His other

books include The Snakes of Honduras, Middle American Herpetology, The Amphibians of Honduras,

Amphibians & Reptiles of the Bay Islands and Cay os Cochinos, Honduras, The Amphibians and Reptiles

of the Honduran Mosquitia, and Guide to the Amph ibians & Reptiles ofCusuco National Park, Honduras.

He also served as the Snake Section Editor for the Catalogue of American Amphibians and Reptiles for

33 years. Over his career, Larry has authored or co-authored the descriptions of 69 currently recognized

herpetofaunal species and six species have been named in his honor, including the anuran Craugastor

lauraster and the snakes Cerrophidion wilsoni, Myriopholis wilsoni, and Oxybelis wilsoni.

Vicente Mata-Silva is a herpetologist interested in ecology, conservation, and the monitoring of amphibians

and reptiles in Mexico and the southwestern United States. His bachelor’s thesis compared herpetofaunal

richness in Puebla, Mexico, in habitats with different degrees of human related disturbance. Vicente’s

master’s thesis focused primarily on the diet of two syntopic whiptail species of lizards, one unisexual

and the other bisexual, in the Trans-Pecos region of the Chihuahuan Desert. Currently, he is a postdoctoral

research fellow at the University of Texas at El Paso, where his work focuses on rattlesnake populations

in their natural habitat. His dissertation was on the ecology of the rock rattlesnake, Crotalus lepidus, in

the northern Chihuahuan Desert. To date, Vicente has authored or co-authored 34 peer-reviewed scientific

publications.

Jerry D. Johnson is Professor of Biological Sciences at The University of Texas at El Paso, and has exten-

sive experience studying the herpetofauna of Mesoamerica. He is the Director of the 40,000 acre “Indio

Mountains Research Station,” was a co-editor on the recently published Conservation of Mesoamerican

Amphibians and Reptiles, and is Mesoamerica/Caribbean editor for the Geographic Distribution section

of Herpetological Review. Johnson has authored or co-authored over 80 peer-reviewed papers, includ-

ing two 2010 articles, “Geographic distribution and conservation of the herpetofauna of southeastern

Mexico” and “Distributional patterns of the herpetofauna of Mesoamerica, a biodiversity hotspot.”

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Appendix 1 . Comparison of the IUCN Ratings from the 2005 Mexican Assessment (updated to the present time) and the Environmental Vulner-

ability Scores for 849 Mexican reptile species (crocodilians, turtles, lizards, and snakes). See text for explanation of the IUCN and EVS rating sys-

tems. * = species endemic to Mexico. 1 = IUCN status needs updating. 2 = Not rated because not recognized as a distinct species. 3 = not described

at the time of assessment.

Species

IUCN

Ratings

Environmental Vulnerability Scores

Geographic

Distribution

Ecological

Distribution

Degree of Human

Persecution

Total

Score

Order Crocodylia (3 species)

Family Alligatoridae (1 species)

Caiman crocodilus

LC 1

3

7

6

16

Family Crocodylidae (2 species)

Crocodylus acutus

VU

3

5

6

14

Crocodylus moreletii

LC

2

5

6

13

Order Testudines (48 species)

Family Cheloniidae (5 species)

Caretta caretta

EN

—

Chelonia mydas

EN

—

Eretmochelys imbricata

CR

—

Lepidochelys kempii

CR

—

Lepidochelys olivacea

VU

—

Family Chelydridae (1 species)

Chelydra rossignonii

VU

4

7

6

17

Family Dermatemydidae (1 species)

Dermatemys mawii

CR

4

7

6

17

Family Dermochelyidae (1 species)

Dermochelys coriacea

CR

—

Family Emydidae (15 species)

Actinemys marmorata

VU

3

8

6

17

Chrysemys picta

LC

3

8

3

14

Pseudemys gorzugi

NT

4

6

16

Terrapene coahuila*

EN

5

8

6

19

Terrapene mexicana*

NE

5

8

6

19

Terrapene nelsoni*

DD

5

7

6

18

Terrapene ornata

NT

3

6

15

Terrapene yucatana*

NE

5

7

6

18

Trachemys gaigeae

VU

4

8

6

18

Trachemys nebulosa*

NE

5

7

6

18

Trachemys ornata*

VU

5

8

6

19

Trachemys scripta

LC

3

7

6

16

Trachemys taylori*

EN

5

8

6

19

Trachemys venusta

NE

3

4

6

13

Trachemys yaquia*

VU

5

8

6

19

Family Geoemydidae (3 species)

Rhinoclemmys areolata

NT

4

6

3

13

Rhinoclemmys pulcherrima

NE

1

4

3

8

Rhinoclemmys rubida*

NT

5

6

3

14

Family Kinosternidae (17 species)

Claudius angustatus

NT 1

4

7

3

14

Kinosternon acutum

NT 1

4

7

3

14

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Conservation reassessment of Mexican reptiles

Kinosternon alamosae*

DD

5

6

3

14

Kinosternon arizonense

LC

4

8

3

15

Kinosternon chimalhuaca*

LC

5

8

3

16

Kinosternon creaseri*

LC

5

7

3

15

Kinosternon durangoense*

DD

5

8

3

16

Kinosternon flavescens

LC

3

6

3

12

Kinosternon herrerai*

NT

5

6

3

14

Kinosternon hirtipes

LC

2

5

3

10

Kinosternon integrum*

LC

5

3

11

Kinosternon leucostomum

NE

3

4

3

10

Kinosternon oaxacae*

DD

5

7

3

15

Kinosternon scorpioides

NE

3

4

3

10

Kinosternon sonoriense

NT

4

7

3

14

Staurotypus salvinii

NT 1

4

6

3

13

Staurotypus triporcatus

NT 1

4

7

3

14

Family Testudinidae (3 species)

Gopherus berlandieri

LC 1

4

8

6

18

Gopherus flavomarginatus*

VU

5

8

6

19

Gopherus morafkai

NE 3

4

5

6

15

Family Trionychidae (2 species)

Apalone atra*

NE

6

8

6

20

Apalone spinifera

LC

3

6

15

Order Squamata (798 species)

Family Bipedidae (3 species)

Bipes biporus*

LC

5

8

1

14

Bipes canaliculatus*

LC

5

6

1

12

Bipes tridactyl us*

LC

5

8

1

14

Family Anguidae (48 species)

Abronia bogerti*

DD

6

8

4

18

Abronia chiszari*

EN

6

7

4

17

Abronia deppii*

EN

6

4

16

Abronia fuscolabialis*

EN

6

8

4

18

Abronia graminea*

EN

5

6

4

15

Abronia leurolepis*

DD

6

8

4

18

Abronia lythrochila*

LC

6

7

4

17

Abronia martindelcampoi*

EN

5

6

4

15

Abronia matudai

EN

4

7

4

15

Abronia mitchelli*

DD

6

8

4

18

Abronia mixteca*

VU

6

8

4

18

Abronia oaxacae*

VU

6

7

4

17

Abronia ochoterenai

DD

4

8

4

16

Abronia ornelasi*

DD

6

8

4

18

Abronia ramirezi*

DD

6

8

4

18

Abronia reidi*

DD

6

8

4

18

Abronia smithi*

LC

6

7

4

17

Abronia taeniata*

VU

5

6

4

15

Anguis ceroni*

NE

5

7

2

14

Anguis incomptus*

NE

5

8

2

15

Baris ia ci Haris*

NE

5

7

3

15

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Wilson et al.

Baris ia herrerae*

EN

5

7

3

15

Barisia imbricata*

LC

5

6

3

14

Barisia jonesi*

NE 2

6

7

3

16

Barisia levicollis*

DD

5

7

3

15

Barisia planifrons*

NE 2

5

7

3

15

Barisia rudicollis*

EN

5

7

3

15

Celestus enneagrammus*

LC

5

6

3

14

Celestus ingridae*

DD

6

8

3

17

Celestus iegnotus*

LC

5

6

3

14

Celestus rozellae

NT

4

6

3

13

Elgaria cedrosensis*

LC

5

8

3

16

Elgaria kingii

LC

2

5

3

10

Elgaria multicarinata

LC

3

4

3

10

Elgaria nana*

LC

5

8

3

16

Elgaria paucicarinata*

VU

5

3

13

Elgaria velazquezi*

LC

5

6

3

14

Gerrhonotus farri*

NE 3

6

8

3

17

Gerrhonotus infernal is*

LC

5

3

13

Gerrhonotus liocephalus

LC

2

1

3

6

Gerrhonotus lugoi*

LC

6

8

3

17

Gerrhonotus ophiurus*

LC

5

4

3

12

Gerrhonotus parvus*

EN

6

8

3

17

Mesaspis antauges*

DD

6

7

3

16

Mesaspis gadovii*

LC

5

6

3

14

Mesaspis juarezi*

EN

5

7

3

15

Mesaspis moreleti

LC

3

9

Mesaspis viridiflava*

LC

5

8

3

16

Family Anniellidae (2 species)

Anniella geronimensis*

EN

5

7

1

13

Anniella pulchra

LC

3

8

1

12

Family Corytophanidae (6 species)

Basiliscus vittatus

NE

1

3

7

Corytophanes cristatus

NE

3

5

3

11

Corytophanes hernandesii

NE

4

6

3

13

Corytophanes percarinatus

NE

4

3

11

Laemanctus longipes

NE

1

5

3

9

Laemanctus serratus

LC

2

3

8

Family Crotaphytidae (10 species)

Crotaphytus antiquus*

EN

5

8

3

16

Crotaphytus collaris

LC

3

7

3

13

Crotaphytus dickersonae*

LC

5

8

3

16

Crotaphytus grismeri*

LC

5

8

3

16

Crotaphytus i ns u laris*

LC

6

7

3

16

Crotaphytus nebrius

LC

2

7

3

12

Crotaphytus reticulatus

VU

4

5

3

12

Crotaphytus vestigium

LC

3

9

Gambelia copeii

LC

2

6

3

11

Gambelia wislizenii

LC

3

7

3

13

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Family Dactyloidae (50 species)

Anolis allisoni

NE

3

7

3

13

Anolis alvarezdeltoroi*

DD

6

8

3

17

Anolis anisolepis*

LC

5

7

3

15

Anolis barkeri*

VU

5

7

3

15

Anolis beckeri

NE 3

3

6

3

12

Anolis biporcatus

NE

3

4

3

10

Anolis breedlovei*

EN

6

7

3

16

Anolis capito

NE

3

6

3

13

Anolis compressicauda*

LC

5

7

3

15

Anolis crassulus

NE

3

4

3

10

Anolis cristifer

DD

4

6

3

13

Anolis cuprinus*

LC

6

7

3

16

Anolis cymbops*

DD

6

8

3

17

Anolis dollfusianus

NE

4

6

3

13

Anolis duellmani*

DD

6

8

3

17

Anolis dunni*

LC

5

8

3

16

Anolis forbesi*

DD

6

7

3

16

Anolis gadovi*

LC

5

8

3

16

Anolis hobartsmithi*

EN

6

3

15

Anolis isthmicus*

DD

5

8

3

16

Anolis laeviventris

NE

3

9

Anolis lemurinus

NE

3

2

3

8

Anolis liogaster*

LC

5

6

3

14

Anolis macrinii*

LC

5

8

3

16

Anolis matudai

NE

4

6

3

13

Anolis megapholidotus*

LC

5

8

3

16

Anolis microlepidotus*

LC

5

7

3

15

Anolis milleri*

DD

5

6

3

14

Anolis naufragus*

VU

5

3

13

Anolis nebuloides*

LC

5

6

3

14

Anolis nebulosus*

LC

5

3

13

Anolis omiltemanus*

LC

5

7

3

15

Anolis parvicirculatus*

LC

6

7

3

16

Anolis petersii

NE

2

4

3

9

Anolis polyrhachis*

DD

5

8

3

16

Anolis pygmaeus*

EN

5

8

3

16

Anolis quercorum*

LC

5

8

3

16

Anolis rodriguezii

NE

4

3

10

Anolis sagrei

NE

2

7

3

12

Anolis schiedii*

DD

5

8

3

16

Anolis schmidti*

LC

5

8

3

16

Anolis sericeus

NE

2

3

8

Anolis serranoi

NE

4

5

3

12

Anolis simmonsi*

DD

5

7

3

15

Anolis subocu laris*

DD

5

7

3

15

Anolis taylori*

LC

5

8

3

16

Anolis tropidonotus

NE

4

2

3

9

Anolis uniformis

NE

4

6

3

13

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Anolis unilobatus

NE 3

1

3

7

Anolis utowanae*

DD

6

8

3

17

Family Dibamidae (1 species)

Anelytropsis papillosus*

LC

5

4

1

10

Family Eublepharidae (7 species)

Coleonyx brevis

LC

4

6

4

14

Coleonyx elegans

NE

2

3

4

9

Coleonyx fasciatus*

LC

5

8

4

17

Coleonyx gypsicolus *

LC

6

8

4

18

Coleonyx reticulatus

LC

4

7

4

15

Coleonyx switaki

LC

4

6

4

14

Coleonyx variegatus

LC

4

3

4

11

Family Gymnophthalmidae (1 species)

Gymnophthalmus speciosus

NE

3

9

Family Helodermatidae (2 species)

Heloderma horridum

LC

2

4

5

11

Heloderma suspectum

NT

4

6

5

15

Family Iguanidae (19 species)

Ctenosaura acanthura

NE

2

4

6

12

Ctenosaura alfredschmidti

NT

4

8

3

15

Ctenosaura dark!*

VU

5

7

3

15

Ctenosaura conspicuosa*

NE

5

8

3

16

Ctenosaura defensor*

VU

5

7

3

15

Ctenosaura hemilopha*

NE

5

7

6

18

Ctenosaura macrolopha*

NE

5

8

6

19

Ctenosaura nolascensis*

NE

6

8

3

17

Ctenosaura oaxacana*

CR

5

8

6

19

Ctenosaura pectinata*

NE

5

4

6

15

Ctenosaura similis

LC

1

4

3

8

Dipsosaurus catalinensis*

NE

6

8

3

17

Dipsosaurus dorsalis

LC

4

3

11

Iguana iguana

NE

3

6

12

Sauromalus ater

LC

4

6

3

13

Sauromalus hispid us*

NT

5

6

3

14

Sauromalus klauberi*

NE

6

7

3

16

Sauromalus slevini*

NE

5

8

3

16

Sauromalus varius*

NE

5

8

3

16

Family Mabuyidae (1 species)

Marisora brachypoda

NE

1

2

3

6

Family Phrynosomatidae (135 species)

Callisaurus draconoides

LC

4

5

3

12

Cophosaurus texanus

LC

4

7

3

14

Holbrookia approximans*

NE

5

6

3

14

Holbrookia elegans

LC

4

6

3

13

Holbrookia lacerata

NT

4

7

3

14

Holbrookia maculata

LC

1

6

3

10

Holbrookia propinqua

LC

4

8

3

15

Petrosaurus mearnsi

LC

4

5

3

12

Petrosaurus repens*

LC

5

3

13

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Petrosaurus slevini*

LC

5

8

3

16

Petrosaurus thalassinus*

LC

5

3

13

Phrynosoma asio

NE

2

6

3

11

Phrynosoma blainvillii

NE

3

7

3

13

Phrynosoma braconnieri*

LC

5

7

3

15

Phrynosoma cerroense*

NE

6

7

3

16

Phrynosoma cornutum

LC

1

7

3

11

Phrynosoma coronatum*

LC

5

4

3

12

Phrynosoma ditmarsi*

DD

5

8

3

16

Phrynosoma goodei

NE

4

6

3

13

Phrynosoma hernandesi

LC

3

7

3

13

Phrynosoma mcallii

NT

4

8

3

15

Phrynosoma modestum

LC

4

5

3

12

Phrynosoma orbiculare*

LC

5

4

3

12

Phrynosoma platyrhinos

LC

3

7

3

13

Phrynosoma solare

LC

4

7

3

14

Phrynosoma taurus*

LC

5

4

3

12

Phrynosoma wigginsi*

NE

5

8

3

16

Sceloporus acanthinus

NE

3

7

3

13

Sceloporus adleri*

LC

5

7

3

15

Sceloporus aeneus*

LC

5

3

13

Sceloporus albiventris*

NE

5

8

3

16

Sceloporus anahuacus*

LC

5

7

3

15

Sceloporus angustus*

LC

5

8

3

16

Sceloporus asper*

LC

5

6

3

14

Sceloporus bicanthalis*

LC

5

3

13

Sceloporus bulled*

LC

5

7

3

15

Sceloporus carinatus

LC

4

5

3

12

Sceloporus cautus*

LC

5

7

3

15

Sceloporus chaneyi*

EN

5

7

3

15

Sceloporus chrysostictus

LC

4

6

3

13

Sceloporus clarkii

LC

2

5

3

10

Sceloporus couchii*

LC

5

7

3

15

Sceloporus cowlesi

NE

4

6

3

13

Sceloporus cozumelae*

LC

5

7

3

15

Sceloporus cryptus*

LC

5

6

3

14

Sceloporus cupreus*

NE

5

8

3

16

Sceloporus cyanogenys*

NE

6

7

3

16

Sceloporus cyanostictus*

EN

5

8

3

16

Sceloporus druckercolini*

NE

5

6

3

14

Sceloporus dugesii*

LC

5

3

13

Sceloporus edwardtaylori*

LC

5

6

3

14

Sceloporus exsul*

CR

6

8

3

17

Sceloporus formosus*

LC

5

7

3

15

Sceloporus gadoviae*

LC

5

3

11

Sceloporus goldmani*

EN

5

7

3

15

Sceloporus grammicus

LC

2

4

3

9

Sceloporus grandaevus*

LC

6

7

3

16

Sceloporus halli*

DD

6

8

3

17

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Sceloporus heterolepis*

LC

5

6

3

14

Sceloporus horrid us*

LC

5

3

11

Sceloporus hunsakeri*

LC

5

6

3

14

Sceloporus ins ignis*

LC

5

8

3

16

Sceloporus internasalis

LC

4

3

11

Sceloporus jalapae*

LC

5

3

13

Sceloporus jarrovii

LC

2

6

3

11

Sceloporus lemosespinali*

DD

5

8

3

16

Sceloporus licki*

LC

5

3

13

Sceloporus lineatulus*

LC

6

8

3

17

Sceloporus lineolateralis*

NE

5

8

3

16

Sceloporus lundelli

LC

4

7

3

14

Sceloporus macdougalli*

LC

5

8

3

16

Sceloporus maculosus*

VU

5

8

3

16

Sceloporus magister

LC

1

5

3

9

Sceloporus marmoratus

NE

2

6

3

11

Sceloporus megalepidurus*

VU

5

6

3

14

Sceloporus melanorhinus

LC

2

4

3

9

Sceloporus merriami

LC

4

6

3

13

Sceloporus minor*

LC

5

6

3

14

Sceloporus mucronatus*

LC

5

3

13

Sceloporus nelsoni*

LC

5

3

13

Sceloporus oberon*

VU

5

6

3

14

Sceloporus occidentalis

LC

3

6

3

12

Sceloporus ochoterenae*

LC

5

4

3

12

Sceloporus olivaceus

LC

4

6

3

13

Sceloporus orcutti

LC

2

3

7

Sceloporus ornatus*

NT

5

8

3

16

Sceloporus palaciosi*

LC

5

7

3

15

Sceloporus parvus*

LC

5

7

3

15

Sceloporus poinsetti

LC

4

5

3

12

Sceloporus prezygus

NE

4

8

3

15

Sceloporus pyrocephalus*

LC

5

4

3

12

Sceloporus salvini*

DD

5

7

3

15

Sceloporus samcolemani*

LC

5

7

3

15

Sceloporus scalaris*

LC

5

4

3

12

Sceloporus serrifer

LC

2

1

3

6

Sceloporus shannonorum*

NE

5

7

3

15

Sceloporus siniferus

LC

2

6

3

11

Sceloporus slevini

LC

2

6

3

11

Sceloporus smaragdinus

LC

4

5

3

12

Sceloporus smithi*

LC

5

7

3

15

Sceloporus spinosus*

LC

5

4

3

12

Sceloporus squamosus

NE

3

5

3

11

Sceloporus stejnegeri*

LC

5

3

13

Sceloporus subniger*

NE

5

7

3

15

Sceloporus subpictus*

DD

6

7

3

16

Sceloporus sugillatus*

LC

5

8

3

16

Sceloporus taeniocnemis

LC

4

5

3

12

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Sceloporus tanneri*

DD

6

7

3

16

Sceloporus teapensis

LC

4

6

3

13

Sceloporus torquatus*

LC

5

3

11

Sceloporus uniformis

NE

3

7

3

13

Sceloporus utiformis*

LC

5

7

3

15

Sceloporus vandenburgianus

LC

4

7

3

14

Sceloporus variabilis

NE

1

3

5

Sceloporus virgatus

LC

4

8

3

15

Sceloporus zosteromus*

LC

5

4

3

12

Uma exsul*

EN

5

8

3

16

Uma notata

NT

4

8

3

15

Uma paraphygas*

NT

6

8

3

17

Uma rufopunctata*

NT

5

8

3

16

Urosaurus auriculatus*

EN

6

7

3

16

Urosaurus bicarinatus*

LC

5

4

3

12

Urosaurus clarionensis*

VU

6

8

3

17

Urosaurus gadovi*

LC

3

6

3

12

Urosaurus graciosus

LC

3

8

3

14

Urosaurus lahtelai*

LC

5

8

3

16

Urosaurus nigricaudus

LC

3

2

3

8

Urosaurus ornatus

LC

2

5

3

10

Uta encantadae*

VU

6

8

3

17

Uta lowei*

VU

6

8

3

17

Uta nolascensis*

LC

6

8

3

17

Uta palmeri*

VU

6

8

3

17

Uta squamata*

LC

6

8

3

17

Uta stansburiana

LC

3

1

3

7

Uta tumidarostra*

VU

6

8

3

17

Family Phyllodactylidae (15 species)

Phyllodactylus bordai*

LC

5

3

13

Phyllodactylus bugastrolepis*

LC

6

8

3

17

Phyllodactylus davisi*

LC

5

8

3

16

Phyllodactylus delcampoi*

LC

5

8

3

16

Phyllodactylus duellmani*

LC

5

8

3

16

Phyllodactylus homolepidurus*

LC

5

7

3

15

Phyllodactylus lanei*

LC

5

7

3

15

Phyllodactylus mural is*

LC

5

6

3

14

Phyllodactylus nocticolus

NE

2

5

3

10

Phyllodactylus partidus*

LC

5

8

3

16

Phyllodactylus paucituberculatus *

DD

6

7

3

16

Phyllodactylus tuberculosus

NE

1

4

3

8

Phyllodactylus u rictus*

NT

5

7

3

15

Phyllodactylus xanti*

LC

5

7

3

15

Thecadactylus rapicauda

NE

3

4

3

10

Family Scincidae (23 species)

Mesoscincus altamirani*

DD

5

6

3

14

Mesoscincus schwartzei

LC

2

6

3

11

Plestiodon bilineatus*

NE

5

3

13

Plestiodon brevirostris*

LC

5

3

11

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Plestiodon callicephalus

LC

2

7

3

12

Plestiodon colimensis*

DD

5

6

3

14

Plestiodon copei*

LC

5

6

3

14

Plestiodon dicei*

NE

5

4

3

12

Plestiodon dugesi*

VU

5

8

3

16

Plestiodon gilberti

LC

3

6

3

12

Plestiodon indubitus*

NE

5

7

3

15

Plestiodon lagunensis*

LC

6

3

15

Plestiodon lynxe*

LC

5

2

3

10

Plestiodon multilineatus*

DD

5

8

3

16

Plestiodon multivirgatus

LC

3

8

3

14

Plestiodon nietoi*

NE

6

8

3

17

Plestiodon obsoletus

LC

3

5

3

11

Plestiodon ochoterenae*

LC

5

3

13

Plestiodon pan/iauriculatus*

DD

5

7

3

15

Plestiodon pan/ulus*

DD

5

7

3

15

Plestiodon skiltonianus

LC

3

5

3

11

Plestiodon sumichrasti

NE

4

5

3

12

Plestiodon tetragrammus

LC

4

5

3

12

Family Sphaerodactylidae (4 species)

Aristelliger georgeensis

NE

3

7

3

13

Gonatodes albogularis

NE

3

5

3

11

Sphaerodactylus continentalis

NE

4

3

10

Sphaerodactylus glaucus

NE

4

5

3

12

Family Sphenomorphidae (6 species)

Scincella gemmingeri*

LC

5

3

11

Scincella kikaapoda*

NE 3

6

8

3

17

Scincella lateralis

LC

3

7

3

13

Scincella silvicola*

LC

5

4

3

12

Sphenomorphus assatus

NE

2

3

7

Sphenomorphus cherriei

NE

3

2

3

8

Family Teiidae (46 species)

Aspidoscelis angusticeps

LC

4

6

3

13

Aspidoscelis bacata*

LC

6

8

3

17

Aspidoscelis burti

LC

4

8

3

15

Aspidoscelis calidipes*

LC

5

6

3

14

Aspidoscelis cana*

LC

5

8

3

16

Aspidoscelis carmenensis*

LC

6

8

3

17

Aspidoscelis catalinensis*

VU

6

8

3

17

Aspidoscelis celeripes*

LC

5

7

3

15

Aspidoscelis ceralbensis*

LC

6

8

3

17

Aspidoscelis communis*

LC

5

6

3

14

Aspidoscelis costata*

LC

5

3

11

Aspidoscelis cozumela*

LC

5

8

3

16

Aspidoscelis danheimae*

LC

6

7

3

16

Aspidoscelis deppii

LC

1

4

3

8

Aspidoscelis espiritensis*

LC

5

8

3

16

Aspidoscelis exanguis

LC

4

7

3

14

Aspidoscelis franciscensis*

LC

6

8

3

17

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Aspidoscelis gularis

LC

2

4

3

9

Aspidoscelis guttata*

LC

5

4

3

12

Aspidoscelis hyperythra

LC

2

5

3

10

Aspidoscelis inornata

LC

4

7

3

14

Aspidoscelis labial is*

VU

5

7

3

15

Aspidoscelis laredoensis

LC

4

7

3

14

Aspidoscelis lineattissima*

LC

5

6

3

14

Aspidoscelis marmorata

NE

4

7

3

14

Aspidoscelis martyris*

VU

6

8

3

17

Aspidoscelis maslini

LC

4

8

3

15

Aspidoscelis mexicana*

LC

5

6

3

14

Aspidoscelis motaguae

LC

4

5

3

12

Aspidoscelis neomexicana

LC

4

8

3

15

Aspidoscelis opatae*

DD

5

8

3

16

Aspidoscelis parvisocia*

LC

5

7

3

15

Aspidoscelis picta*

LC

6

8

3

17

Aspidoscelis rodecki*

NT

5

8

3

16

Aspidoscelis sackii*

LC

5

6

3

14

Aspidoscelis semptemvittata

LC

3

7

3

13

Aspidoscelis sexlineata

LC

3

8

3

14

Aspidoscelis sonorae

LC

4

6

3

13

Aspidoscelis stictogramma

NE

4

7

3

14

Aspidoscelis tesselata

LC

4

7

3

14

Aspidoscelis tigris

LC

3

2

3

8

Aspidoscelis uniparens

LC

4

8

3

15

Aspidoscelis xanthonota

NE

4

7

3

14

Holcosus chaitzami

DD

4

7

3

14

Holcosus festiva

NE

3

5

3

11

Holcosus undulatus

NE

2

3

7

Family Xantusiidae (25 species)

Lepidophyma chicoasense*

DD

6

8

2

16

Lepidophyma cuicateca*

NE 3

6

8

2

16

Lepidophyma dontomasi*

DD

6

2

14

Lepidophyma flavimaculatum

NE

1

5

2

8

Lepidophyma gaigeae*

VU

5

6

2

13

Lepidophyma lineri*

DD

5

8

2

15

Lepidophyma lipetzi*

EN

6

8

2

16

Lepidophyma lowei*

DD

6

8

2

16

Lepidophyma micropholis*

VU

5

8

2

15

Lepidophyma occulor*

LC

5

7

2

14

Lepidophyma pajapanense*

LC

5

6

2

13

Lepidophyma radula*

DD

6

5

2

13

Lepidophyma smithii

NE

2

4

2

8

Lepidophyma sylvaticum*

LC

5

4

2

11

Lepidophyma tarascae*

DD

5

7

2

14

Lepidophyma tuxtlae*

DD

5

4

2

11

Lepidophyma zongolica*

NE 3

6

8

2

16

Xantusia bolsonae*

DD

6

8

3

17

Xantusia extorris*

LC

5

7

3

15

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Xantusia gilberti*

NE

5

8

3

16

Xantusia henshawi

LC

4

5

3

12

Xantusia jaycolei*

NE

5

8

3

16

Xantusia sanchezi*

LC

5

8

3

16

Xantusia sherbrookei*

NE

5

8

3

16

Xantusia wigginsi

NE

4

7

3

14

Family Xenosauridae (9 species)

Xenosaurus agrenon*

NE

5

4

3

12

Xenosaurus grandis*

VU

5

1

3

9

Xenosaurus newmanorum*

EN

5

7

3

15

Xenosaurus penai*

LC

6

7

3

16

Xenosaurus phalaroanthereon*

DD

5

8

3

16

Xenosaurus platyceps*

EN

5

6

3

14

Xenosaurus rackhami

NE

4

3

11

Xenosaurus rectocol laris*

LC

5

8

3

16

Xenosaurus tzacualtipantecus*

NE

6

8

3

17

Family Boidae (2 species)

Boa constrictor

NE

3

1

6

10

Charina trivirgata

LC

4

3

10

Family Colubridae (136 species)

Arizona elegans

LC

1

3

5

Arizona pacata*

LC

5

4

14

Bogertophis rosaliae

LC

2

5

3

10

Bogertophis subocularis

LC

4

7

3

14

Chilomeniscus savagei*

LC

6

7

2

15

Chilomeniscus stramineus

LC

4

2

8

Chionactus occipitalis

LC

4

6

2

12

Chionactus palarostris

LC

4

7

2

13

Coluber constrictor

LC

1

6

3

10

Conopsis acuta*

NE

5

7

2

14

Conopsis amphisticha*

NT

5

8

2

15

Conopsis biserial is*

LC

5

6

2

13

Conopsis lineata*

LC

5

6

2

13

Conopsis megalodon*

LC

5

7

2

14

Conopsis nasus*

LC

5

4

2

11

Dendrophidion vinitor

LC

3

7

3

13

Drymarchon melanurus

LC

1

4

6

Drymobius chloroticus

LC

1

3

4

8

Drymobius margaritiferus

NE

1

4

6

Ficimia hardyi*

EN

5

6

2

13

Ficimia olivacea*

NE

5

2

9

Ficimia publia

NE

4

3

2

9

Ficimia ramirezi*

DD

6

8

2

16

Ficimia ruspator*

DD

6

8

2

16

Ficimia streckeri

LC

3

7

2

12

Ficimia variegata*

DD

5

7

2

14

Geagras redimitus*

DD

5

7

2

14

Gyalopion canum

LC

4

3

2

9

Gyalopion quadrangulare

LC

3

6

2

11

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Lampropeltis alterna

LC

4

7

3

14

Lampropeltis californiae

NE 2

3

4

3

10

Lampropeltis catalinensis*

DD

6

8

3

17

Lampropeltis herrerae*

CR

6

8

3

17

Lampropeltis holbrooki

NE 2

3

8

3

14

Lampropeltis knoblochi

NE 2

2

5

3

10

Lampropeltis mexicana*

LC

5

7

3

15

Lampropeltis ruthveni*

NT

5

8

3

16

Lampropeltis splendida

NE 2

4

5

3

12

Lampropeltis triangulum

NE

1

5

7

Lampropeltis webbi*

DD

5

8

3

16

Lampropeltis zonata

LC

3

7

5

15

Leptophis ahaetulla

NE

3

4

10

Leptophis diplotropis*

LC

5

4

14

Leptophis mexicanus

LC

1

4

6

Leptophis modestus

VU

3

7

4

14

Liochlorophis vernalis

LC

3

8

3

14

Masticophis anthonyi*

CR

6

8

3

17

Masticophis au rig ulus*

LC

5

4

13

Masticophis barbouri*

DD

6

8

3

17

Masticophis bilineatus

LC

2

5

4

11

Masticophis flagellum

LC

1

3

4

8

Masticophis fuiiginosus

NE

2

3

4

9

Masticophis lateralis

LC

3

4

10

Masticophis mentovarius

NE

1

4

6

Masticophis schotti

LC

4

5

4

13

Masticophis slevini*

LC

6

8

3

17

Masticophis taeniatus

LC

1

5

4

10

Mastigodryas cliftoni*

NE

5

6

3

14

Mastigodryas melanolomus

LC

1

4

6

Opheodrys aestivus

LC

3

7

3

13

Oxybelis aeneus

NE

1

3

5

Oxybelis fulgidus

NE

3

2

4

9

Pantherophis bairdi

NE

4

7

4

15

Pantherophis emoryi

LC

3

6

4

13

Phyllorhynchus browni

LC

4

7

2

13

Phyllorhynchus decurtatus

LC

4

5

2

11

Pituophis catenifer

LC

4

1

4

9

Pituophis deppei*

LC

5

4

14

Pituophis insulanus*

LC

6

4

16

Pituophis lineaticollis

LC

2

4

8

Pituophis vertebral is*

LC

5

3

4

12

Pseudelaphe flavirufa

LC

2

4

10

Pseudelaphe phaescens*

NE

5

7

4

16

Pseudoficimia frontalis*

LC

5

3

13

Pseustes poecilonotus

LC

3

4

3

10

Rhinocheilus antonii*

NE

5

8

3

16

Rhinocheilus etheridgei*

DD

6

7

3

16

Rhinocheilus lecontei

LC

1

3

4

8

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Salvadora bairdi*

LC

5

6

4

15

Salvadora deserticola

NE

4

6

4

14

Salvadora grahamiae

LC

4

2

4

10

Salvadora hexalepis

LC

4

2

4

10

Salvadora intermedia*

LC

5

7

4

16

Salvadora lemniscata*

LC

5

6

4

15

Salvadora mexicana*

LC

5

6

4

15

Scaphiodontophis annulatus

NE

1

5

11

Senticolis triaspis

NE

2

1

3

6

Sonora aemula*

NT

5

6

5

16

Sonora michoacanensis*

LC

5

6

3

14

Sonora mutabilis*

LC

5

6

3

14

Sonora semiannulata

LC

1

3

5

Spilotes pullatus

NE

1

4

6

Stenorrhina degenhardtii

NE

3

9

Stenorrhina freminvillii

NE

1

2

4

7

Symphimus leucostomus*

LC

5

6

3

14

Symphimus mayae

LC

4

7

3

14

Sympholis lippiens*

NE

5

6

3

14

Tantilla atriceps

LC

2

7

2

11

Tantilla bocourti*

LC

5

2

9

Tantilla briggsi*

DD

6

8

2

16

Tantilla calamarina*

LC

5

2

12

Tantilla cascadae*

DD

6

8

2

16

Tantilla ceboruca*

NE

6

8

2

16

Tantilla coronadoi*

LC

6

7

2

15

Tantilla cuniculator

LC

4

7

2

13

Tantilla deppei*

LC

5

6

2

13

Tantilla flavilineata*

EN

5

7

2

14

Tantilla gracilis

LC

3

8

2

13

Tantilla hobartsmithi

LC

3

6

2

11

Tantilla impensa

LC

3

5

2

10

Tantilla johnsoni*

DD

6

8

2

16

Tantilla moesta

LC

4

7

2

13

Tantilla nigriceps

LC

3

6

2

11

Tantilla oaxacae*

DD

6

7

2

15

Tantilla planiceps

LC

4

3

2

9

Tantilla robusta*

DD

6

8

2

16

Tantilla rubra

LC

2

1

2

5

Tantilla schistosa

NE

3

2

8

Tantilla sertula*

DD

6

8

2

16

Tantilla shawi*

EN

5

8

2

15

Tantilla slavensi*

DD

5

7

2

14

Tantilla striata*

DD

5

7

2

14

Tantilla tayrae*

DD

6

7

2

15

Tantilla triseriata*

DD

5

6

2

13

Tantilla vulcani

NE

4

6

2

12

Tantilla wilcoxi

LC

2

6

2

10

Tantilla yaquia

LC

2

6

2

10

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Tantillita brevissima

LC

4

3

2

9

Tantillita canula

LC

4

6

2

12

Tantillita lintoni

LC

4

6

2

12

Trimorphodon biscutatus

NE

2

1

4

7

Trimorphodon lambda

NE

4

5

4

13

Trimorphodon lyrophanes

NE

4

2

4

10

Trimorphodon paucimaculatus*

NE

5

6

4

15

Trimorphodon tau*

LC

5

4

13

Trimorphodon vilkinsonii

LC

4

7

4

15

Family Dipsadidae (115 species)

Adelphicos latifasciatum*

DD

6

7

2

15

Adelphicos newmanorum*

NE

5

2

12

Adelphicos nigrilatum*

LC

5

7

2

14

Adelphicos quadrivirgatum

DD

4

2

10

Adelphicos sargii

LC

4

6

2

12

Amastridium sapperi

NE

4

2

10

Chersodromus liebmanni*

LC

5

2

12

Chersodromus rubriventris*

EN

5

7

2

14

Coniophanes alvarezi*

DD

6

8

3

17

Coniophanes bipunctatus

NE

1

5

3

10

Coniophanes fissidens

NE

1

3

7

Coniophanes imperialis

LC

2

3

8

Coniophanes lateritius*

DD

5

3

13

Coniophanes melanocephalus*

DD

5

6

3

14

Coniophanes meridanus*

LC

5

7

3

15

Coniophanes michoacanensis*

NE 3

6

8

3

17

Coniophanes piceivittis

LC

1

3

7

Coniophanes quinquevittatus

LC

4

6

3

13

Coniophanes sarae*

DD

5

7

3

16

Coniophanes schmidti

LC

4

6

3

13

Coniophanes taylori*

NE

5

7

4

16

Cryophis hallbergi*

DD

5

7

2

14

Diadophis punctatus

LC

1

2

4

Dipsas brevifacies

LC

4

7

4

15

Dipsas gaigeae*

LC

5

8

4

17

Enuiius flavitorques

NE

1

3

5

Enulius oligostichus*

DD

5

7

3

15

Geophis anocu laris*

LC

6

8

2

16

Geophis bicolor*

DD

5

8

2

15

Geophis blanchardi*

DD

5

8

2

15

Geophis cancellatus

LC

4

6

2

12

Geophis carinosus

LC

2

4

2

8

Geophis chalybeus*

DD

6

7

2

15

Geophis dubius*

LC

5

6

2

13

Geophis duellmani*

LC

5

8

2

15

Geophis dugesi*

LC

5

6

2

13

Geophis immaculatus

LC

4

8

2

14

Geophis incomptus*

DD

6

8

2

16

Geophis isthmicus*

DD

6

8

2

16

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Geophis juarezi*

DD

6

8

2

16

Geophis juliai*

VU

5

6

2

13

Geophis latici rictus*

LC

5

4

2

11

Geophis laticol laris*

DD

6

8

2

16

Geophis lati frontal is*

DD

5

7

2

14

Geophis maculiferus*

DD

6

8

2

16

Geophis mutitorques*

LC

5

6

2

13

Geophis nasalis

LC

4

3

2

9

Geophis nigrocinctus*

DD

5

8

2

15

Geophis occabus*

NE 3

6

8

2

16

Geophis omiltemanus*

LC

5

8

2

15

Geophis petersi*

DD

5

8

2

15

Geophis pyburni*

DD

6

8

2

16

Geophis rhodogaster

LC

3

7

2

12

Geophis russatus*

DD

6

8

2

16

Geophis sallei*

DD

6

7

2

15

Geophis semidoliatus*

LC

5

6

2

13

Geophis sieboldi*

DD

5

6

2

13

Geophis tarascae*

DD

5

8

2

15

Heterodon kenneriyi

NE

3

4

11

Hypsigiena affinis*

NE

5

7

2

14

Hypsiglena chlorophaea

NE

1

5

2

8

Hypsigiena jani

NE

1

3

2

6

Hypsiglena ochrorhyncha

NE

2

4

2

8

Hypsigiena slevini*

NE

5

4

2

11

Hypsiglena tanzeri*

DD

5

8

2

15

Hypsiglena torquata*

LC

5

1

2

8

Imantodes cenchoa

NE

1

3

2

6

Imantodes gemmistratus

NE

1

3

2

6

Imantodes tenuissimus

NE

4

7

2

13

Leptodeira frenata

LC

4

12

Leptodeira maculata

LC

2

1

4

7

Leptodeira nigrofasciata

LC

1

3

4

8

Leptodeira punctata*

LC

5

8

4

17

Leptodeira septentrionalis

NE

2

4

8

Leptodeira splendida*

LC

5

4

14

Leptodeira uribei*

LC

5

8

4

17

Ninia diademata

LC

4

3

2

9

Ninia sebae

NE

1

2

5

Pliocercus elapoides

LC

4

1

5

10

Pseudoleptodeira latifasciata *

LC

5

4

14

Rhadinaea bogertorum*

DD

6

8

2

16

Rhadinaea cuneata*

DD

6

7

2

15

Rhadinaea decorata

NE

1

6

2

9

Rhadinaea forbesi*

DD

5

8

2

15

Rhadinaea fulvivittis*

VU

5

4

2

11

Rhadinaea gaigeae*

DD

5

2

12

Rhadinaea hesperia*

LC

5

3

2

10

Rhadinaea laureata*

LC

5

2

12

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Rhadinaea macdougalli*

DD

5

2

12

Rhadinaea marcel lae*

EN

5

2

12

Rhadinaea montana*

EN

5

7

2

14

Rhadinaea myersi*

DD

5

2

12

Rhadinaea omiltemana*

DD

5

8

2

15

Rhadinaea quinquelineata*

DD

5

8

2

15

Rhadinaea taeniata*

LC

5

6

2

13

Rhadinella godmani

NE

3

5

2

10

Rhadinella hannsteini

DD

4

5

2

11

Rhadinella kanalchutchan*

DD

6

8

2

16

Rhadinella kinkelini

LC

4

6

2

12

Rhadinella lachrymans

LC

4

2

8

Rhadinella posadasi

NE

4

8

2

14

Rhadinella schistosa*

LC

5

6

2

13

Rhadinophanes monticola*

DD

6

7

2

15

Sibon dimidiatus

LC

1

5

4

10

Si bon linearis*

DD

6

8

2

16

Sibon nebulatus

NE

1

2

5

Sibon sanniolus

LC

4

6

2

12

Tantalophis discolor*

VU

5

6

3

14

Tropidodipsas annulifera*

LC

5

4

13

Tropidodipsas fasciata*

NE

5

4

13

Tropidodipsas fischeri

NE

4

3

4

11

Tropidodipsas philippi*

LC

5

4

14

Tropidodipsas repleta*

DD

5

8

4

17

Tropidodipsas sartorii

NE

2

5

9

Tropidodipsas zweifeli*

NE

5

7

4

16

Family Elapidae (19 species)

Laticauda colubrina

LC

—

Micruroides euryxanthus

LC

4

6

5

15

Micrurus bernadi*

LC

5

15

Micrurus bogerti*

DD

5

7

5

17

Micrurus browni

LC

2

1

5

8

Micrurus diastema

LC

2

1

5

8

Micrurus distans*

LC

5

4

5

14

Micrurus elegans

LC

4

5

13

Micrurus ephippifer*

VU

5

15

Micrurus laticol laris*

LC

5

4

5

14

Micrurus latifasciatus

LC

4

5

13

Micrurus limbatus*

LC

5

7

5

17

Micrurus nebu laris*

DD

5

8

5

18

Micrurus nigrocinctus

NE

3

5

11

Micrurus pachecogili*

DD

6

7

5

18

Micrurus proximans*

LC

5

8

5

18

Micrurus tamaulipensis*

DD

6

8

5

19

Micrurus tener

LC

1

5

11

Pelamis platura

LC

—

Family Leptotyphlopidae (8 species)

Epictia goudotii

NE

1

3

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Rena boettgeri*

NE

5

8

1

14

Rena bressoni*

DD

5

8

1

14

Rena dissecta

LC

4

6

1

11

Rena dulcis

LC

4

8

1

13

Rena humilis

LC

4

3

1

8

Rena maxima*

LC

5

1

11

Rena myopica*

LC

5

7

1

13

Family Loxocemidae (1 species)

Loxocemus bicolor

NE

1

5

4

10

Family Natricidae (33 species)

Adelophis copei*

VU

5

8

2

15

Adelophis foxi*

DD

6

8

2

16

Nerodia erythrogaster

LC

3

4

11

Nerodia rhombifer

LC

1

5

4

10

Storeria dekayi

LC

1

4

2

7

Storeria hidalgoensis*

VU

5

6

2

13

Storeria storerioides*

LC

5

4

2

11

Thamnophis bogerti*

NE

5

7

4

16

Thamnophis chrysocephalus*

LC

5

4

14

Thamnophis conanti*

NE

5

8

4

17

Thamnophis cyrtopsis

LC

2

1

4

7

Thamnophis elegans

LC

3

7

4

14

Thamnophis eques

LC

2

4

8

Thamnophis errans*

LC

5

7

4

16

Thamnophis exsul*

LC

5

7

4

16

Thamnophis fulvus

LC

4

5

4

13

Thamnophis godmani*

LC

5

4

14

Thamnophis hammondii

LC

4

5

4

13

Thamnophis lineri*

NE

5

8

4

17

Thamnophis marcianus

NE

1

5

4

10

Thamnophis melanogaster*

EN

5

6

4

15

Thamnophis mendax*

EN

5

4

14

Thamnophis nigronuchalis*

DD

5

3

4

12

Thamnophis postremus*

LC

5

6

4

15

Thamnophis proximus

NE

1

2

4

7

Thamnophis pulch hiatus*

LC

5

6

4

15

Thamnophis rossmani*

DD

6

8

4

18

Thamnophis rufipunctatus

LC

4

7

4

15

Thamnophis scalaris*

LC

5

4

14

Thamnophis scaliger*

VU

5

6

4

15

Thamnophis sirtalis

LC

3

7

4

14

Thamnophis sumichrasti*

LC

5

6

4

15

Thamnophis validus*

LC

5

3

4

12

Family Typhlopidae (2 species)

Typhlops microstomus

LC

4

7

1

12

Typhlops tenuis

LC

4

6

1

11

Family Ungaliophiidae (2 species)

Exiliboa placata*

VU

5

8

2

15

Ungaliophis continentalis

NE

3

5

2

10

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June 2013 I Volume 7 I Number 1 I e61

Conservation reassessment of Mexican reptiles

Family Viperidae (59 species)

Agkistrodon bilineatus

NT

1

5

11

Agkistrodon contortrix

LC

3

6

5

14

Agkistrodon taylori*

LC

5

7

5

17

Atropoides mexicanus

NE

3

4

5

12

Atropoides nummifer*

LC

5

3

5

13

Atropoides occiduus

NE

4

6

5

15

Atropoides olmec

LC

4

6

5

15

Bothriechis aurifer

VU

3

6

5

14

Bothriechis bicolor

LC

4

5

14

Bothriechis rowleyi*

VU

5

6

5

16

Bothriechis schlegelii

NE

3

4

5

12

Bothrops asper

NE

3

4

5

12

Cerrophidion godmani

NE

3

5

11

Cerrophidion petlalcalensis*

DD

5

8

5

18

Cerrophidion tzotzilorum*

LC

6

8

5

19

Crotalus angelensis*

LC

6

7

5

18

Crotalus aquilus*

LC

5

6

5

16

Crotalus atrox

LC

1

3

5

9

Crotalus basiliscus*

LC

5

6

5

16

Crotalus catalinensis*

CR

6

8

5

19

Crotalus cerastes

LC

4

7

5

16

Crotalus culminatus*

NE

5

15

Crotalus enyo*

LC

5

3

5

13

Crotalus ericsmithi*

NE

5

8

5

18

Crotalus estebanensis*

LC

6

8

5

19

Crotalus helleri

NE

4

3

5

12

Crotalus intermedius*

LC

5

15

Crotalus lannomi*

DD

6

8

5

19

Crotalus lepidus

LC

2

5

12

Crotalus lorenzoensis*

LC

6

8

5

19

Crotalus mitchellii

LC

4

3

5

12

Crotalus molossus

LC

2

1

5

8

Crotalus muertensis*

LC

6

8

5

19

Crotalus ornatus

NE

4

5

13

Crotalus polystictus*

LC

5

6

5

16

Crotalus price i

LC

2

7

5

14

Crotalus pusillus*

EN

5

8

5

18

Crotalus ravus*

LC

5

4

5

14

Crotalus ruber

LC

2

5

9

Crotalus scutulatus

LC

2

4

5

11

Crotalus simus

NE

3

2

5

10

Crotalus stejnegeri*

VU

5

7

5

17

Crotalus tancitarensis*

DD

6

8

5

19

Crotalus tigris

LC

4

7

5

16

Crotalus totonacus*

NE

5

7

5

17

Crotalus transversus*

LC

5

7

5

17

Crotalus triseriatus*

LC

5

6

5

16

Crotalus tzabcan

NE

4

7

5

16

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June 2013 I Volume 7 I Number 1 I e61

Wilson et al.

Crotalus viridis

LC

1

6

5

12

Crotalus willardi

LC

2

6

5

13

Mixcoatlus barbouri*

EN

5

15

Mixcoatlus browni*

NE

5

7

5

17

Mixcoatlus melanurus*

EN

5

7

5

17

Ophryacus undulatus*

VU

5

15

Porthidium dunni*

LC

5

6

5

16

Porthidium hespere*

DD

5

8

5

18

Porthidium nasutum

LC

3

6

5

14

Porthidium yucatanicum*

LC

5

7

5

17

Sistrurus catenatus

LC

3

5

13

Family Xenodontidae (8 species)

Clelia scytalina

NE

4

5

4

13

Conophis lineatus

LC

2

3

4

9

Conophis morai*

DD

6

7

4

17

Conophis vittatus

LC

2

5

4

11

Manolepis putnami*

LC

5

3

13

Oxyrhopus petolarius

NE

3

6

5

14

Tretanorhinus nigroluteus

NE

3

5

2

10

Xenodon rabdocephalus

NE

3

5

13

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June 2013 I Volume 7 I Number 1 I e61

Cantils (genus Agkistrodon ) are some of the most feared snakes in Mesoamerica, as their bite and powerful venom have caused

numerous human fatalities. Equipped with a large and strikingly-marked head, a stout body, and a nervous attitude that often is mis-

taken for aggression, these snakes usually are killed on sight. Cantils primarily are found in tropical forests that undergo a prolonged

dry season, but occasionally inhabit savannas and areas that flood seasonally after heavy rains. Pictured here is a cantil from Parque

Nacional Santa Rosa, in northwestern Costa Rica. Photo by Louis W. Porras.

June 2013 I Volume 7 I Number 1 I e63

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048

Attribution-NonCommercial-NoDerivs 3.0 Unported License, which permits unrestricted use for non-commer-

cial and education purposes only provided the original author and source are credited.

Amphibian & Reptile Conservation 7(1): 48-73.

A taxonomic reevaluation and conservation assessment of

the common cantil, Agkistrodon bilineatus (Squamata:

Viperidae): a race against time

1 Louis W. Porras, 2 Larry David Wilson, 34 Gordon W. Schuett,

and 4 Randall S. Reiserer

1 7705 Wyatt EarpAvenue, Eagle Mountain, Utah, 84005, USA 2 CentroZamoranodeBiodiversidad, EscuelaAgncolaPanamericanaZamorano, Francisco

Morazdn, HONDURAS; 16010 S. W. 207th Avenue, Miami, Florida, 33187, USA 3 Department of Biology and Center for Behavioral Neuroscience,

Georgia State University, Atlanta, Georgia, 30303, USA 4 The Copperhead Institute, P.O. Box 6755, Spartanburg, South Carolina 29304, USA

Abstract. — Several lines of evidence suggest that numerous populations of cantils (Agkistrodon bi-

lineatus, A. taylori), New World pitvipers with a distribution in Mesoamerica, are in rapid decline. We

examined the IUCN conservation status for A. bilineatus, assessed for the entire range of the spe-

cies, as well as the Environmental Vulnerability Scores (EVS) provided for certain countries along

its distribution. Because of pronounced disparities in these conservation assessments and notable

phenotypic differences that coincide with the geographic distribution of certain cantil populations,

we conduct a taxonomic reassessment of the common cantil, Agkistrodon bilineatus (Gunther

1863), to determine if the recognized subspecies of A. bilineatus merit specific status. Based on

our morphological assessment, biogeographical evidence, and the results of previous DNA-based

studies, we elevate the three previously recognized subspecies of A. bilineatus to full species (A.

bilineatus, A. russeolus, and A. howardgloydi). Given this taxonomic reassessment, we examine the

conservation status of the newly elevated taxa, suggest avenues for future studies within this com-

plex of pitvipers, and provide conservation recommendations.

Key words. Character evolution, evolutionary species, Mesoamerica, subspecies concept

Resumen. — Varias lineas de evidencia sugieren que numerosas poblaciones de cantiles ( Agkistrodon

bilineatus, A. taylori), viboras de foseta del Nuevo Mundo con una distribucion en Mesoamerica, es-

tan en rapido declive. Examinamos los resultados sobre el estado de conservacion propuestos por

la UICN para A. bilineatus, que fueron evaluados para la distribucion total de la especie, asi como

los resultados de los Indices de Vulnerabilidad Ambiental (en ingles, Environmental Vulnerability

Scores [EVS]) que fueron determinados para esta especie en algunos paises a lo largo de su distri-

bucion. Por haber disparidades pronunciadas en estas evaluaciones de conservacion y diferencias

fenotipicas notables que coinciden con la distribucion geografica de ciertas poblaciones de can-

tiles, en este trabajo realizamos una reevaluacion taxonomica del cantil comun, Agkistrodon biline-

atus (Gunther 1863), para determinar si las subespecies reconocidas de A. bilineatus merecen el

estatus de especie. Basado en nuestro analisis morfologico, evidencia biogeografica y los resulta-

dos de anteriores estudios basados en ADN, elevamos las tres subespecies de A. bilineatus previa-

mente reconocidas al nivel de especie (A. bilineatus, A. russeolus y A. howardgloydi). Tomando en

cuenta esta nueva evaluacion taxonomica, examinamos el estado de conservacion de los taxones

aqui elevados, hacemos sugerencias para estudios futuros dentro de este complejo de viboras de

foseta y ofrecemos recomendaciones para su conservacion.

Palabras claves. Evolucion de caracteres, especies evolutivas, Mesoamerica, concepto de subespecies

Citation: Porras LW, Wilson LD, Schuett GW, Reiserer RS. 2013. A taxonomic reevaluation and conservation assessment of the common cantil,

Agkistrodon bilineatus (Squamata: Viperidae): a race against time. Amphibian & Reptile Conservation 7(1): 48-73 (e63).

Correspondence. Emails: 1 empub@msn.com (Corresponding author) 2 bufodoc@ aol.com gwschuett@yahoo.com

4 rreiserer@ gmail. com

June 2013 I Volume 7 I Number 1 I e63

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049

Porras et al.

Although the restoration of tropical dry forest is still pos-

sible, humanity will not give the globe back to its wild-

land denizens, and old-growth tropical dry forest will

never again cover large areas.

Janzen 2004: 80.

Introduction

The common cantil ( Agkistrodon bilineatus) is a poly-

typic species of North American pitviper with a variably

fragmented distribution extending from extreme south-

western Chihuahua and southern Sonora, Mexico, to

northwestern Costa Rica, on the Pacific versant, and parts

of the Yucatan Peninsula, northern Belize, Guatemala,

and extreme western Honduras on the Atlantic versant;

it also occurs in Las Islas Marias, an archipelago of four

islands located about 100 km west of the state of Nayarit,

Mexico (Gloyd and Conant 1990; Campbell and Lamar

2004; Lemos-Espinal and Smith 2007; Babb and Dugan

2008; Garcfa-Grajales and Buenorostro-Silva 2011;

McCranie 2011). With few exceptions, the dominant

vegetation zones occupied by A. bilineatus are dry for-

est, deciduous forest, thorn scrub, and savanna, primarily

areas of low relief that have been exploited heavily for

irrigated agriculture and where this species mostly has

become a rare snake; the elevational range of A. bilinea-

tus extends from near sea level to about 1,500 m (Gloyd

and Conant 1990; Conant 1992). Along the Pacific coast

of Mesoamerica, tropical dry forests were reported as the

most endangered of the major tropical ecosystems, with

only 0.09% of that region afforded official conservation

status (Janzen 1988). A quarter of a century after Janzen’s

elucidative paper, aside from protected areas, dry forests

throughout this region have continued to deteriorate.

In a monographic study of the Agkistrodon complex,

Gloyd and Conant (1990) provided an extensive review

of the cantils, including information on their taxonomy,

morphology, distribution, and aspects of their natural

history. Based on multiple lines of evidence, Parkinson

et al. (2002) conducted a phylogeographic analysis of

the cantils and elevated A. b. taylori to the rank of full

species, emphasizing that the loss of forested areas in

the habitat of this species underscored the need for its

conservation. More recently, Wilson et al. (2010) com-

piled an extensive conservation assessment for the en-

tire Mesoamerican herpetofauna, in which numerous

authorities provided information on the status of can-

tils. Although the methodological approaches of these

authors varied, it was clear from the outcome that the

conservation status of A. bilineatus showed dramatic

differences when analyzed on a country by country or

regional basis, since the reported or estimated IUCN

rankings for this species extended the gamut from Least

Concern to Critically Endangered (Lavin-Murcio and

Lazcano 2010; Sasa et al. 2010). Some authors also

Amphib. Reptile Conserv. | http://amphibian-reptile-conservation.org 050

provided Environmental Vulnerability Scores (EVS; a

conservation measure developed and used by Wilson and

McCranie 1992, 2004, and McCranie and Wilson 2002)

for certain countries, and their results were more infor-

mative. This measure provides a rough gauge of the theo-

retical degree that herptofaunal species are vulnerable to

environmental degradation; the scores at the upper end

of the scale (ranging from 14 to 20) indicate a greater de-

gree of concern (Wilson et al. 2013), and the EVS for A.

bilineatus was reported as 15 for Honduras, Nicaragua,

and Costa Rica, and as 16 for Belize (Sasa et al. 2010;

Stafford et al. 2010; Sunyer and Kohler 2010; Townsend

and Wilson 2010).

Based on our field experiences, recent discussions

with several colleagues working in regions where cantils

occur, and information from the published literature, we

echo the statements of several of the aforementioned au-

thorities that in many regions A. bilineatus has declined

significantly, largely as a result of human activities.

Our principal goal in this paper is to reexamine the

conservation status of A. bilineatus , inasmuch as the

available information suggests that certain populations

are declining or imperiled. In conservation biology the

threat status of an organism typically is evaluated at the

species level, so first we reevaluate the taxonomic status

of the three subspecies of A. bilineatus ( bilineatus , rus-

seolus, and howardgloydi ) to determine if any (or all) of

them shows sufficient lineage divergence to warrant full

species recognition. Accordingly, our conservation as-

sessment develops from our taxonomic conclusions.

Morphological Assessment

Gloyd and Conant (1990) and Campbell and Lamar

(2004) provided an extensive amount of biological in-

formation on cantils, including excellent drawings of the

scalation and pattern of the relevant taxa discussed in

this paper, so we relied largely on these sources for our

morphological assessment. Unlike previous views (see

Gloyd and Conant 1990), the genus Agkistrodon now is

restricted to the New World (see Molecular Assessment).

As in other pitviper genera, Agkistrodon (sensu

stricto) is characterized by the presence of a deep fa-

cial pit, a vertically elliptical pupil, a large venom

gland in the temporal region, and a canaliculated fang

on the maxilla followed by a series of smaller replace-

ment fangs. In Agkistrodon , however, the scales on the

crown generally are large and plate-like, although often

they are fragmented or contain partial sutures, and the

skull is relatively broad and equipped with short fangs.

Other characters include a pronounced canthus rostra-

lis, the presence of a loreal scale in all members except

A. piscivorus, a robust (or relatively robust) body, and a

moderate to long tail. Scale characters such as supralabi-

als, infralabials, and dorsal scale rows at midbody show

little variation among the species, although the last of

these characters is slightly higher in A. piscivorus. The

June 2013 I Volume 7 I Number 1 I e63

Taxonomy and conservation of the common cantil

number of ventral scales is lower in A. bilineatus and A.

taylori than in A. contortrix and A. piscivorus, and the

number of subcaudals is slightly lower in the latter two

species. In Agkistrodon, some or most of the subcaudal

scales are divided, and the terminal spine on the tail tip

is turned downward in all the taxa except A. piscivorus.

Moderate hemipenial differences have been reported

among the taxa, but the similarities are more pronounced

when comparing A. contortrix and A. piscivorus to A. bi-

lineatus and A. taylori (Gloyd and Conant 1990; Malnate

1990). The tail tip of neonates and juveniles of all spe-

cies of Agkistrodon is brightly colored and typically is

yellow, white, or pink (Gloyd and Conant 1990). The

coloration of the tail tip changes as animals mature, to a

faded yellow, green, gray, black, or sometimes to match

the color of the dorsum. Young individuals often use their

tail to lure prey (e.g., anurans, lizards) by way of vertical

undulations and waving, a behavior termed “caudal lur-

ing” (reviewed by Strimple 1988, 1992; Carpenter and

Gillingham 1990).

1. The cantils

Commonly known as cantils, A. bilineatus and A. taylori

are thick-bodied pitvipers (Serpentes: Viperidae) with a

large head and a moderately long and slender tail, and

their maximum total lengths are similar. As in the other

species of Agkistrodon , the scale characters of cantils

only show a moderately low range of variation (Table 1).

A wide range of color pattern variation is evident in

Agkistrodon , and these characters were used to diag-

nose the three subspecies of A. bilineatus (Burger and

Robertson 1951; Gloyd 1972; Conant 1984), as well to

elevate A. taylori to the rank of full species (Parkinson

et al. 2000). The coloration of the head is distinctive, as

cantils are adorned with five conspicuous pale stripes,

one vertically on the front of the snout and two laterally

on each side of the head. The dorsal color pattern con-

sists of crossbands, at least in juveniles, and this char-

acter shows a notable degree of geographic and ontoge-

netic variation. The chin color and ventral coloration also

demonstrate considerable geographic variation.

2. Color and pattern characteristics of the

ornate cantil

Among the cantils, the color pattern of A. taylori is the

most vivid (Fig.l). The lower facial stripe is broad and

extends to cover the lower edge of the supralabials, the

dorsal pattern is composed of pronounced black cross-

bands separated by gray or pale brown areas that often

contain yellowish brown or orange, the chin is patterned

with bold markings with wide white or yellow elements,

and the venter contains dark gray or black markings

Fig. 1 . Adult female Agkistrodon taylori from Aldamas, Tamaulipas, Mexico. The ornate cantil often is vividly marked.

Photo by Tim Burkhardt.

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051

Porras et al.

Table 1. Maximum total length and selected scale characters in the three subspecies of Agkistrodon bilineatus and in A. taylori.

Min-max values are followed by the mean (in parentheses). Data derived from Gloyd and Conant (1990).

Character

A. b. bilineatus

A. b. russeolus

A. b. howardgloydi

A. taylori

Total length

1,090 mm

1,050 mm*

960 mm

Ventrals

127-143 (134.5)

131-141 (136.1)

128-135 (131.1)

127-138 (133.7)

Subcaudals

52-71 (61.6)

46-62 (55.4)

54-61 (58.8)

40-56 (48.3)

Supralabials

5-9 (8.1)

8-9 (8.0)

7-9 (8.0)

Infralabials

9-13(10.7)

8-12(10.8)

9-12(10.9)

9-12 (10.4)

Dorsal scale rows

(midbody)

21-25 (22.9)

23-25 (23.1)

23-25 (23.4)

21-23 (22.9)

* Specimen with an incomplete tail.

arranged in a somewhat checkerboard pattern. In contrast

to juveniles, adults exhibit a subdued pattern that con-

tains brighter colors, but older individuals of both sexes

tend to become melanistic, and sexual color dimorphism

is present in all age classes (Burchfield 1982). The tail tip

of young individuals has been reported as sulphur yellow,

ivory white, or salmon pink (Burchfield 1982; Gloyd and

Conant 1990); the tail tip of most young individuals,

however, is sulphur yellow (LWP, GWS, pers. observ.;

Fig. 2).

Fig. 2. Neonate female Agkistrodon taylori born in captivity

from adults collected in the state of Tamaulipas, Mexico. Sexual

color pattern dimorphism is evident in all age classes, except in

very old individuals that sometimes darken with age. In young

males, the rhombs on the dorsum tend to form bands and the

interstitial pattern is reduced. Photo by Breck Bartholomew.

3. Color and pattern characteristics of the

common cantil

In A. b. bilineatus, both the upper and lower facial stripes

are relatively broad, and the lower stripe is continuous

and bordered below by dark pigment along the mouth

line. From a frontal view, the vertical stripe along the

rostral and mental and the lateral head stripes often meet

on the tip of the snout. In adults, the dorsal ground color

ranges from very dark brown to black, and if crossbands

are present often they are difficult to distinguish. The

dorsal pattern consists of small white spots or streaks.

The chin and throat are dark brown or black with a pat-

tern of narrow white lines or markings, and the venter is

dark brown or black with pale markings. The coloration

of neonates and juveniles is some shade of brown, and

consists of brown or chestnut crossbands separated by a

paler ground color, with the lateral edges of the cross-

bands flecked with white. The crossbands gradually fade

with maturity, however, as the overall dorsal coloration

darkens (Fig. 3). The tail tip of neonates and juveniles

has been reported in numerous publications as bright yel-

low (e.g., Allen 1949; Gloyd and Conant 1990). Sexual

color dimorphism has not been reported in any age class.

In A. b. russeolus, the upper facial stripe is narrow

and sometimes is intermittent posterior to the eye, and

the lower stripe is broader and continuous and separated

from the commissure by a band of dark pigment. From a

frontal view, the vertical stripe along the rostral and men-

tal and the two upper lateral head stripes typically meet

on the tip of the snout. The dorsal ground color of adults

generally is pale reddish brown, and the pattern consists

of broad, deep reddish brown to brown crossbands that

are separated dorsally by areas of paler coloration, and

often are edged irregularly with white. The crossbands

remain apparent, even in older adults. Laterally, the cen-

ters of the crossbands are paler and usually contain one

or two dark spots. The pattern on the chin and throat of-

ten is reduced, with small whitish spots or lines present

on a darker background. Approximately the median third

of the venter lacks a pattern or contains a few markings.

The coloration of a neonate (150 to 175 mm TL) col-

lected near Merida, Yucatan, was described from life

by Howard K. Gloyd (Gloyd and Conant 1990: 83) as

showing a velvety appearance, and its pattern consisted

of rich chestnut-brown crossbands with rufous brown

interspaces, which were edged with blackish brown and

interrupted lines of white, “and the tip of the tail gray.”

A neonate from Dzibilchaltun, Yucatan, showed a similar

coloration except that the banding was edged intermit-

tently only with white, and the tail tip was pale gray with

faint white banding (Fig. 4). This individual was main-

tained in captivity and by the time it had grown to a total

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052

Fig. 3. Young adult Agkistrodon b. bilineatus from Apatzingan, Michoacan, Mexico, at an elevation of 330 m. Adult individuals

from much of the west coast of Mexico often lose the dorsal banding (see cover of this issue). Photo by Javier Alvarado.

Fig. 4. Neonate Agkistrodon bilineatus russeolus from

Dzibilchaltun, Yucatan, Mexico. Note the pale gray tail tip with

faint white banding, and the overall dorsal color pattern.

Photo by Javier Ortiz.

Fig. 5. Juvenile (ca. 400 mm TL) Agkistrodon bilineatus russeo-

lus from Dzibilchaltun, Yucatan, Mexico (same individual as in

Fig. 4). With growth, the inner portion of the crossbands turned

the same color as the interspaces, and the snake’s pattern de-

veloped a more fragmented appearance. Photo by Javier Ortiz.

length of ca. 400 mm, a marked transformation in color

pattern had taken place (Fig. 5). With growth, the inner

portion of the crossbands gradually turned the same pale

color as the interspaces and the individual’s pattern de-

veloped a more fragmented appearance; the color of the

tail tip also shifted to include darker gray tones (Fig. 5).

Henderson (1978) reported the dorsal pattern of a pre-

served young individual (ca. 380 mm) from Orange Walk

Town, Orange Walk District, Belize, as faintly banded,

and the tail as grayish-yellow with faint narrow bands.

Although Gloyd and Conant (1990: 83) reported the tail

tip of an individual from the same locality as “bright

green,” they did not indicate the total length of the snake

and an ontogenetic color shift might have occurred. The

fragmentation of the banding in A. b. russeolus is appar-

ent in the photograph of an adult collected in the outskirts

of Consejo, Corozal, Belize (Fig. 6). Sexual color dimor-

phism has not been reported in juveniles or adults of A.

b. russeolus.

In A. b. howardgloydi, the upper facial stripe is narrow

and the posterior part often is absent in adults, and the

lower facial stripe is broader and usually divided into

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Taxonomy and conservation of the common cantil

Fig. 6. Adult Agkistrodon bilineatus russeolus from the outskirts of Consejo, Corozal, Belize. Note the fragmented color pattern.

Photo by Kevin Zansler, courtesy of Robert A. Thomas.

Fig. 7. Adult Agkistrodon bilineatus howardgloydi from Volcan Telica, Leon,

Nicaragua. The color pattern of individuals from this volcanic region often contains

black pigment. Photo by Nony Sonati, courtesy of Javier Sunyer.

components that sometimes meet at the suture between

the second and third suprlabials, and below is bordered

by a dark line; the lower edges of the supralabials also are

pale in color. From a frontal view, of the five facial stripes

only the top two generally meet on

the tip of the snout, but in some

individuals all five stripes are con-

nected. The dorsal ground color of

adults generally is reddish brown or

brown. Adults with black pigment,

however, are known from Reserva

Natural Volcan Telica in northwest-

ern Nicaragua, with a pattern con-

sisting of darker crossbands that

contrast moderately with the dorsal

ground color, and along this volcanic

area adults sometimes show a dark

coloration (J. Sunyer, pers. comm.;

Figs. 7, 8). A cantil also was sighted

on the eastern shore of Laguna de

Xiloa, north of Managua (R. Earley,

pers. comm.). The chin and throat

are orange yellow, bright orange, or

brownish orange with a pattern of a

few small white spots, but this col-

oration terminates abruptly after the

first few ventrals. The venter usually

is dark reddish brown. The dorsal coloration of juveniles

is tan to reddish orange, or reddish, with distinguishable

reddish brown crossbands that are edged intermittently

with white and/or black, especially as they approach

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Porras et al.

Fig. 8. Young Agkistrodon bilineatus howardgloydi from Volcan Masaya, Masaya,

Nicaragua. The color pattern of adults from this area sometimes darkens with age.

Photo by Javier Sunyer.

Fig 9. Juvenile (311 mm TL) Agkistrodon bilineatus howardgloydi from Parque

Nacional Santa Rosa, Guanacaste, Costa Rica. Note the color pattern of the tail tip,

which anteriorly to posteriorly turns from very dark to pale gray with corresponding

pale gray to white interspaces. Photo by Alejandro Solorzano.

the venter. The tail tip of juveniles

is banded with a sequential pattern

that ranges from very dark gray an-

teriorly to paler gray toward the tip,

with the interspaces alternating from

pale gray to white (Fig. 9). Although

Villa (1984: 19) indicated that in

Nicaragua “the bright sulphur-

yellow tail of the young becomes

dark in the adult,” and a photograph

of a “juvenile individual” of A. b.

howardgloydi with what is indicated

as a “yellowish tail” appears on the

frontispiece, the robust body features

of the snake clearly show that it is

not a juvenile and its tail is not yel-

low. We question, therefore, whether

Villa might not have assumed that

the tail color of A. b. howardgloydi

would be yellow, as this information

long was entrenched in literature re-

garding A. b. bilineatus. With regard

to sexual color dimorphism, unlike

the other subspecies of A. bilineatus,

sub-adults and adults of A. b. how-

ardgloydi show a moderate degree

of sexual color dimorphism; in indi-

viduals from Costa Rica, females are

distinctly banded and paler in overall

coloration, whereas males tend to be

darker, with their banding obscured

(Figs. 10, 11). Metachrosis, the abil-

ity to change color at will or under

external stimuli (such as light), was

observed in the holotype of A. b.

howardgloydi (Conant 1984). The

coloration of this individual was

paler at night (LWP, pers. observ.).

055

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Taxonomy and conservation of the common cantil

Fig. 10. Adult female Agkistrodon bilineatus howardgloydi from Colonia Jobo de la Cruz, Guanacaste, Costa Rica. The color pattern

of subadults and adults is paler in females. Photo by Louis W. Porras.

Fig. 11. Adult male A. b. howardgloydi (holotype) from 0.8 kilimeters north of Mirador Canon del Tigre, Parque Nacional Santa

Rosa, Guanacaste, Costa Rica. The color pattern of subadults and adults is darker in males. Photo by Louis W. Porras.

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Porras et al.

Molecular Assessment

Gloyd and Conant (1990) recognized 33 taxa (spe-

cies and subspecies) in Agkistrodon (sensu lato), with a

distribution in the Old World and the New World, but

subsequent studies using molecular (mtDNA) methods

partitioned Agkistrodon and demonstrated that the name

applies to a monophyletic group of species restricted to

the New World (Knight et al. 1992; Kraus et al. 1996;

Parkinson et al. 1997, 2002; Parkinson 1999; Castoe and

Parkinson 2006; Malhotra et al. 2010). Agkistrodon cur-

rently is viewed as containing four species, A. bilineatus,

A. contortrix, A. piscivorus, and A. taylori (Parkinson et

al. 2000; Campbell and Lamar 2004), although one sub-

species of A. piscivorus and two of A. contortrix appear

to constitute distinct species (Guiher and Burbrink 2008;

Douglas et al. 2009).

1. Molecular studies of cantils

Parkinson et al. (2000) provided the first phylogeo-

graphic (mtDNA) analysis of cantils, and tested all of the

recognized subspecies ( bilineatus , howardgloydi, rus-

seolus, and taylori). Using maximum parsimony (MP)

and maximum likelihood (ML) methods, these authors

recovered the clades ( taylori + ( bilineatus ( howardgloydi

-t- russeolus ))). Furthermore, based on additional lines

of evidence (e.g., biogeography, morphology) they rec-

ommended the elevation of taylori to full species status,

whereas the remaining subspecies were thought to be

more recently diverged (i.e., having shallower relation-

ships). Using other mtDNA regions (ATPase 8 and 6),

and both ML and Bayesian methods of analyses, Douglas

et al. (2009) corroborated the results of Knight et al.

(1992) and Parkinson et al. (2000) with respect to New

World Agkistrodon, including the relationships of cantils,

although in their study they lacked DNA samples of A. b.

russeolus.

2. Current views of cantil systematics and

taxonomy

Despite efforts by the various aforementioned authori-

ties, a considerable gap in our understanding of the tax-

onomy and phylogeography of cantils remains. We at-

tribute this outcome largely to insufficient sampling,

based on the number of specimens used in their analy-

ses and the number of localities sampled. For example,

Knight et al. (1992) included only two samples of can-

tils ( bilineatus and taylori ) and both lacked locality in-

formation, although their samples of taylori presumably

were collected in Tamaulipas, Mexico (A. Knight, pers.

comm.). Similarly, Parkinson et al. (2000) reported on

only seven samples of cantils, of which two lacked lo-

cality data, and their respective samples of taylori (n =

2) and howardgloydi (n = 2) each came from the same

locality (see Parkinson et al. 2000: table 2). In testing

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phylogeographic hypotheses in Agkistrodon, Guiher and

Burbrink (2008) and Douglas et al. (2009) used extensive

sampling of A. contortrix and A. piscivorus, and both

studies used cantils as an outgroup. No new localities for

cantils, however, were sampled.

Presently, only limited mtDNA-based sequence data

(no nuclear genes have been tested) are available for a

handful of specimens of cantils. No definitive molecular

information exists for the no min ate form, A. b. bilinea-

tus (i.e., no study has provided precise locality informa-

tion) and only one specimen of A. b. russeolus (Yucatan,

Mexico) has been subjected to a DNA-based inquiry

(Parkinson et al. 2000). Given the extensive range of can-

tils, the limited number of specimens sampled and tested

thus far (Mexico: Tamaulipas [no specific locality],

Yucatan, [no specific locality]; Costa Rica: Guanacaste

Province, Santa Rosa) is inadequate to provide a robust

view of their phylogeography. Nonetheless, despite these

deficiencies, the available molecular (mtDNA) evidence

suggests that the three subspecies of cantils (A. b. bilin-

eatus, A. b. howardgloydi, and A. b. russeolus ) can be

diagnosed as separate evolutionary entities (per Wiley

1978, 1981).

Character Mapping

Character mapping is a powerful analytical procedure

for producing information and gaining insights into

character evolution, particularly with respect to origin,

direction, and frequency (Brooks and McLennan 1991;

Harvey and Pagel 1991; Martins 1996; Fenwick et al.

2011; Maddison and Maddison 2011). Ideally, characters

(traits) should be traced onto trees constructed from an

explicitly independent data set (Harvey and Pagel 1991;

Maddison and Maddison 2011), such as morphological

characters mapped onto trees constructed using mol-

ecules (e.g., proteins, DNA).

1. Methods

We conducted a character mapping analysis (CMA) of

the cantils by using morphological data derived from the

literature (Gloyd and Conant 1990; Campbell and Lamar

2004), new information presented in this paper, and un-

published personal data on all species of Agkistrodon

(sensu stricto) (see Appendix 1). All characters were

coded as binary (i.e., 0, 1) or multi-state (e.g., 0, 1, 2).

Non-discrete multi-state characters (e.g., color pattern)

were ordered from lowest to highest values. Character

polarity was established by using two congeners (A. con-

tortrix and A. piscivorus ) as outgroups. The cottonmouth

(A. piscivorus) is confirmed as the sister group to cantils

(Douglas et al. 2009). Ten characters were selected as

potential apomorphies (shared-derived traits) and were

traced onto a fully resolved tree (six taxa) based on the

mtDNA-markers used in Parkinson et al. (2000) and

Douglas et al. (2009). Character tracing was performed

June 2013 I Volume 7 I Number 1 | e63

Taxonomy and conservation of the common cantil

separately for each of the 10 traits using outgroup analy-

sis and parsimony procedures in Mesquite (Madison and

Madison 2011), and then combining the individual re-

sults onto a global tree.

2. Results and discussion

We found 10 morphological characters (scutellation,

color pattern traits) selected for the CMA useful in pro-

viding broad support for the topology of the molecular

tree, as well as robust evidence for the distinctiveness of

the taxa, in particular the three subspecies of A. bilinea-

tus (Table 2). We thus assign these characters as putative

synapomorphies and autapomorphies for Agkistrodon

(Fig. 12). Although we had a priori knowledge of spe-

cific and unique traits used to originally diagnose each of

the subspecies, the CMA presents them in a phylogenetic

and temporal framework. Accordingly, we show trait

evolution with respect to origin, direction, and frequency.

For example, we recovered dark dorsal coloration (dark

brown or black) as the putative ancestral condition of

Agkistrodon (Outgroup 1), which is retained in the basal-

most cantils (A. taylori and A. b. bilineatus ), but evolved

to reddish-brown in the sister clade A. b. howardgloydi +

A. b. russeolus. These types of data can be used in CMA

to test explicit hypotheses concerning adaptation, such

as seeking correlations of body color to climate, habitat

types, and a range of other variables (e.g., Martins 1996).

Allopatry in A. bilineatus

In prioritizing a list of vipers for future conservation mea-

sures, Greene and Campbell (1992: 423) considered A.

bilineatus (sensu lato) a taxon of special interest because

of its “highly fragmented and biogeographically interest-

ing distribution.” Parkinson et al. (2002) also commented

on the relictual nature of the distribution of cantils, and

used allopatry as one of their criteria for elevating A. b.

taylori to species level.

As presently understood, the distribution of A. b.

bilineatus extends along the Pacific coast of Mexico

(including the offshore Las Islas Marias) and northern

Central America, from extreme southwestern Chihuahua

and southern Sonora to central El Salvador; inland in

Mexico, this species has been recorded in northwest-

ern and extreme southeastern Morelos, as well as in the

Rio Grijalva Valley (Central Depression; Johnson et al.

2010) of Chiapas (Gloyd and Conant 1990; Campbell

and Lamar 2004; Castro-Franco and Bustos Zagal 2004;

Herrera et al. 2006; Lemos-Espinal and Smith 2007;

Garcfa-Grajales and Buenorostro-Silva 2011). McCranie

(2011) included a photograph of a cantil from extreme

western Honduras (Copan, Copan). Based on that pho-

tograph, and others provided to us by the collector (R.

Garrado, pers. comm.) taken after the animal had reached

maturity, the color pattern characteristics of this individ-

ual are most similar to those of A. b. bilineatus (Fig. 13).

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Table 2. Morphological characters used in the character map-

ping analysis (Fig. 12). See text for details.

Character

State

Designation

Facial striping

absent

A0

present

Al

Upper facial stripe

absent

B0

variable

B1

broad

B2

narrow

B3

Adult coloration

tan

CO

black/dark brown

Cl

reddish-brown

C2

Adult dorsal band

no

DO

(same as ground color)

yes

D1

Adult dorsal band

brown

E0

color (when present)

black/dark brown

El

multi-colored

E2

reddish-brown

E3

Throat color

ground-color

F0

cream/white

FI

multi-colored

F2

dark

F3

brown

F4

yellow-orange

F5

Juvenile to adult

slight

GO

color ontogeny

pronounced

G1

moderate

G2

Neonate tail-tip color

yellow

HO

gray

HI

Neonate tail pattern

slight

10

moderate

11

pronounced

12

Sexual color

absent

JO

dimorphism

present

J1

A photograph of what appears to be A. b. bilineatus , with

a locality of Honduras, also appears in Kohler (2001: fig.

264). The distribution of A. b. russeolus primarily extends

along the outer part of the Yucatan Peninsula, from west-

central Campeche and the northern portion of Yucatan and

Quintana Roo on the Gulf side, and in northern Belize on

the Caribbean side, although isolated records are avail-

able from extreme southeastern Campeche and central

Peten, Guatemala (Gloyd and Conant 1990; Campbell

1998; Campbell and Lamar 2004; Kohler 2008). The

southernmost population of cantil (A. b. howardgloydi )

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Porras et al.

AO- JO

Fig. 12. Character mapping analysis of morphological traits in cantils (A. b. bilineatus,

A. b. howardgloydi, A. b. russeolus, and A. taylori ). Outgroup 1 = A. piscivorus;

Outgroup 2 = A. contortrix. See Table 2 and Appendix 1 .

Fig. 13. Young adult Agkistrodon b. bilineatus from La Chorcha Lodge, Copan,

Honduras at an elevation of 610 m (2,000 feet). Two sighting of this species have

occurred at the lodge, in 2003 and 2008. Photo by Robert Gallardo.

occurs along the Pacific coast of

Central America from Isla Zacate

Grande, in the Golfo de Fonseca,

and the adjacent mainland of south-

ern Honduras to the southern limit

of Parque Nacional Santa Rosa Park

in northwestern Costa Rica (Sasa

and Solorzano 1995).

The taxonomic assignment of

certain populations of A. bilineatus,

however, remains problematical. A

single individual of cantil was re-

ported from north of Palma Sola,

in central coastal Veracruz, an area

disjunct from that of all other popu-

lations (Blair et al. 1997). Smith

and Chiszar (2001) described the

specimen as a new subspecies (A.

b. lemosespinali ), but Campbell and

Lamar (2004: 266) indicated that

this taxon “was diagnosed by sev-

eral characteristics, all of which are

within the normal range of variation

for A. taylori or might be artifacts

in a specimen preserved for more

than 30 years.” After examining

additional specimens of A. taylori

from Hidalgo and Veracruz, how-

ever, Bryson and Mendoza-Quijano

(2007) concluded that the speci-

men was most closely related to, if

not conspecific with, A. b. bilinea-

tus, but that it also differed from all

of the subspecies of A. bilineatus

in its tail length to total length ra-

tio. Bryson and Mendoza-Quijano

(2007) further commented that the

presence of A. bilineatus in coastal

Veracruz lends corroboration to the

transcontinental dispersal hypoth-

esis presented by Parkinson et al.

( 2002 ).

Another isolated population is

known from the Atlantic versant

of central Guatemala, from the Rfo

Chixoy (Negro) Valley (Campbell

and Lamar 1989). Gloyd and Conant

(1990) commented that two speci-

mens from this area show similari-

ties in color pattern to each of the

three populations of A. bilineatus

occurring in Central America. Until

additional specimens and/or molec-

ular data are available, however, the

taxonomic status of this allopatric

population is uncertain and remains

for future investigation. Similarly,

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059

Taxonomy and conservation of the common cantil

the population in the Central Depression of Chiapas,

Mexico, and adjacent western Guatemala merits further

examination.

In summary, the distribution of A. bilineatus is disjunct

or fragmented throughout its extensive range, and thus

we contend that three identifiable areas of its distribution

are biogeographically distinct. Except for certain issues

that remain unresolved (see Discussion), these regions of

allopatry constitute the ranges of A. b. bilineatus , A. b.

russeolus, and A. b. howardgloydi (see Distribution Map

[Fig. 14] below).

Our Taxonomic Position

Six decades ago, Wilson and Brown (1953) discussed the

recognition of subspecies in biology and were among the

first to advocate, with compelling academic vigor, to halt

the use of trinomials in taxonomy. Since their provoca-

tive paper was published, a flurry of literally hundreds of

papers on the utility of infraspecific categories has ap-

peared, of which many applauded the insights of Wilson

and Brown (1953) and supported abandoning the recogni-

tion of subspecies (e.g., Edwards 1954; Donoghue 1985;

Ball and Avise 1992; Douglas et al. 2002; Zink 2004),

whereas others criticized their views as biologically short

sighted (e.g., Sibley 1954; Durrant 1955; Crusz 1986;

Mallet 1995). Even with the application of an integrative

taxonomic approach (reviewed by Padial and de la Riva

2010), a unified concept of species and consequences

for solving the problems of species delimitation (see de

Queiroz 2007), or a general species concept approach as

presented by Hausdorf (2011), no perfect solutions are

available to resolve all of the conflicting viewpoints.

Nevertheless, Padial and de la Riva (2010: 748) argued

that on the basis of the evolutionary species concept, “the

point of separation from [a] sister lineage is what marks

the origin of a species... and neither subspecies nor ‘sub-

speciation’ are logically needed.” Importantly, this state-

ment implies that there are no “stages of speciation,” i.e.,

subspecies are not “on their way” to becoming species.

We also share the opinion of Johnson et al. (2010: 327),

who asserted that the species level is “the lowest evolu-

tionary lineage segment that should be used in a formal

phylogenetically based taxonomy... In this modern taxo-

nomic hierarchy, all taxa except for subspecies are hy-

pothesized to consist of separate evolutionary lineages,

and thus subspecies should not be recognized as a formal

taxonomic unit.” Moreover, today new subspecies rarely

are described in most major zoological journals, although

many authors retain already-recognized subspecies as a

provisional measure (e.g., Oatley et al. 2011). Here, we

adopt the position on subspecies outlined by Wilson and

Brown (1953) and subsequently supported by hundreds

of biologists (reviewed by Burbrink et al. 2000; Douglas

et al. 2002; Johnson et al. 2010).

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Taxonomic Conclusions

The taxonomic overview and analysis we provide for

the three putative subspecies of the common cantil (A.

b. bilineatus, A. b. russeolus, and A. b. howardgloydi )

substantiates that sufficient morphological (color and

pattern), molecular (mtDNA), and ecological (biogeo-

graphical) data are available to consider these taxa as

separate and diagnosable entities with their own evolu-

tionary trajectories (see Wiley 1981; Wiley and May den

2000; Douglas et al. 2002). As we view it necessary to

adopt and identify a species concept (Padial and de la

Riva 2010), we used the evolutionary species concept

(ESC) introduced by Wiley (1978, 1981). We agree with

others that the ESC is preferred among the species hy-

potheses, since it best accommodates both morphologi-

cal and molecular information (Wiley and May den 2000;

Schwentner et al. 2011).

Accordingly, we elevate the three subspecies of A.

bilineatus to full species and suggest the following com-

mon names: Agkistrodon bilineatus (common cantil),

A. russeolus (Yucatecan cantil), and A. howardgloydi

(southern cantil). We indicate the reported localities for

all the cantils, including A. taylori, in a distribution map

(Fig. 14).

Conservation Assessment

Up to 2006, the conservation status of Agkistrodon bili-

neatus (sensu lato) was judged by the IUCN as Least

Concern, but in 2007, presumably as a result of the rep-

tile assessment undertaken in September 2005, in Jalisco,

Mexico, the status was changed to Near Threatened

(IUCN Red List website; accessed 20 February 2013).

Given that we elevated each of the three subspecies of A.

bilineatus to full species, we will assess their conserva-

tion status individually.

1. Application of the IUCN rankings

The IUCN categories for assigning conservation status

are the most widely used scheme for attempting to as-

sess the degree of extinction risk for taxa at the species

level (www.iucnredlist.org). The criteria used for this

assessment are stipulated in the Guidelines for Using

the IUCN Red List Categories and Criteria (Version

8.1; August 2010). Those with the greatest application

to Mesoamerican reptile populations involve the extent

of occurrence (i.e., geographic range), and at least two

criteria regarding the degree of range fragmentation, the

degree of decline in one of a number of distributional or

populational characteristics, or the degree of fluctuations

in any of these characteristics. The extent of occurrence

is related to the threat categories as follows: Critically

Endangered (< 100 km 2 ); Endangered (< 5,000 km 2 ); and

Vulnerable (< 20,000 km 2 ).

June 2013 I Volume 7 I Number 1 I e63

Porras et al.

Q Agkistrodon t&ylori

£ Agkistrodon bilineatus

O Agkistrodon russeolus

O Undetermined

San Juanita

Maria Madre

Q' .

I M^rra Magdalena

? <] Man’s Cleofas

Las [si as Manas

= IMI \ IH

2in» mi

Fig. 14. Distribution map of the reported localities for cantils, including some indicated in this paper. Green is used to designate

localities from where we regard the systematic status of cantils as undetermined.

Under our new taxonomic arrangement, the distribu-

tion of A. bilineatus (sensu stricto) is extended to include

extreme western Honduras, in the vicinity of the city of

Copan on the Caribbean versant (McCranie 2011). Thus,

its extent of distribution well exceeds the 20,000 km 2

that forms the upper cutoff for a Vulnerable species; it

also is greater than the 250,000 km 2 indicated by Garcia

(2006) as the combined extent of the six dry forest ecore-

gions in Pacific coastal Mexico, in addition to its range

in Central America. Given its approximate geographic

distribution, it clearly lies outside of the upper size limits

for any of the IUCN threat categories. In addition, this

species does not appear to qualify as Near Threatened,

given that “the taxon should be close to qualifying for

the Vulnerable category. The estimates of population size

or habitat should be close to the Vulnerable thresholds,

especially when there is a high degree of uncertainty”

(IUCN 2010: 63). If, however, A. bilineatus cannot be

judged as Near Threatened, only three other categories

are available, viz., Extinct, Least Concern, and Data

Deficient. The species is not Extinct, or as we maintain

in this paper not of Least Concern, and also does not clas-

sify as Data Deficient because enough information was

Amphib. Reptile Conserv. | http://amphibian-reptile-conservation.org 061

available for it to be judged as Near Threatened (Lee and

Hammerson 2007). In light of this information, we con-

tend that A. bilineatus (sensu stricto) should be judged

as Near Threatened. A broad-scale assessment of this

snake’s conservation status throughout its distribution

is extremely critical, however, since much of its area of

occurrence has been subjected to considerable human

population growth.

In Mexico, A. bilineatus primarily occurs in the

coastal portion of nine states from Sonora to Chiapas, as

well as in Morelos. According to information obtained

from Wikipedia (www.wikipedia.org), here and else-

where in this section, these 10 states have a combined

human population of 33,432,935 (29.0% of the 2012

population of Mexico). With a growth rate of 1.4% for

the country (Population Reference Bureau 2010) and

an estimated doubling time of 50 years, if these growth

rates remain comparable the population of these states

will reach 66,865,870 by the year 2063. Although these

figures and projections apply to an area greater than the

total range of A. bilineatus in Mexico, they signal grave

concern for the survival of these populations.

June 2013 I Volume 7 I Number 1 I e63

Taxonomy and conservation of the common cantil

The prospects for the future of A. bilineatus in

Guatemala and El Salvador are equally as disturbing.

Guatemala is the most rapidly growing country in Central

America, with a human population 13,824,463 in 2011,

a growth rate of 2.8%, and an estimated doubling time of

25 years, and El Salvador already has become the most

densely populated region in Mesoamerica. These statis-

tics, therefore, portend a gloomy picture for the flora and

fauna of these countries.

Consequently, in light of these data, we consider A.

bilineatus as Near Threatened, while conceding that fu-

ture population analyses might demonstrate a threatened

status.

The distribution of A. russeolus is much greater

than 100 km 2 (the upper cutoff point for a Critically

Endangered species), but significantly less than 5,000

km 2 (the upper cutoff point for an Endangered species).

Thus, based on the extent of occurrence, A. russeolus

should be judged as an Endangered species. According

to the maps in Gloyd and Conant (1990), Lee (1996),

Campbell and Lamar (2004), and Kohler (2008), A. rus-

seolus is known from up to twelve localities, depend-

ing on the level of discrimination. Most of these locali-

ties are from the state of Yucatan, from the vicinity of

Merida, Motul, and Piste. Given this number of locations

( n = 12), A. russeolus should be assessed as Vulnerable,

since the criterion for this category is < 10, as opposed to

Endangered, which is < 5. These records are historical,

however, with some dating prior to 1895 (sensu Gloyd

and Conant 1990), and to our knowledge no modem sur-

vey has been undertaken to ascertain the viability of can-

til populations in these regions.

The human population of the three Mexican states

occupying the Yucatan Peninsula, Campeche, Yucatan,

and Quintana Roo, is over 4,000,000 (Population Refer-

ence Bureau 2010). Most of the historical records for

A. russeolus are from the state of Yucatan, the most

populous of the three with a current population of about

2,000,000. Specimens assigned to A. russeolus have been

reported from seasonally dry forest in northern Belize,

from Corozal and northern Belize Districts (Stafford

and Meyer 2000), and the savanna area of central Peten,

Guatemala (Campbell 1998).

Lee and Hammerson (2007) indicated that the major

factor affecting the long-term viability of populations of

A. bilineatus (sensu lato) is “the extreme pressure from

persecution leading to population reductions of close

to 30% over the last 15 to 30 years...” According to

J. Lee (pers. comm.), this evaluation cannot be applied

precisely to A. russeolus, but would point to a Critically

Endangered status based on criterion Cl, i.e., an estimate

of continuing decline of at least 25% in 3 years or one

generation (IUCN 2010). Lee (1996: 399) commented

that, u Agkistrodon bilineatus [sensu lato] is a danger-

ously venomous snake that is widely feared by the na-

tive people of Yucatan. It is believed to be capable of

Amphib. Reptile Conserv. | http://amphibian-reptile-conservation.org 062

prodigious jumps and to deliver venom both through

its bite and with its tail, which is thought to act as a

stinger...” Lee (1996: 416) also discussed the historical

and the modern attitude toward snakes in general and A.

russeolus (as A. bilineatus ) in particular, in his chapter

on ethnoherpetology in the Yucatan Peninsula, indicating

that the cantil or uolpoch (the Mayan name) “is consid-

ered by many contemporary Maya to be the most danger-

ous of all Yucatecan snakes.” This attitude translates into

this snake being killed on sight (J. Lee, pers. comm.).

Consequently, based on the available information on the

conservation status of A. russeolus, we consider this spe-

cies as Endangered. A conservation assessment needs to

be undertaken, however, to determine if this categoriza-

tion is appropriate, or whether the category of Critically

Endangered would be more applicable.

Agkistrodon howardgloydi is distributed in appar-

ently fragmented populations that extend from Isla

Zacate Grande in the Golfo de Fonseca and the adja-

cent mainland of southern Honduras (McCranie 2011),

western Nicaragua in the area west of Rio Tipitapa and

the northwestern shore of Lago de Nicaragua (Kohler

1999, 2001), and in extreme northwestern Costa Rica

from Bahia Salinas, near the Nicaraguan border, to the

s

sectors of Santa Rosa and Guanacaste, both in Area de

Conservacion Guanacaste (Conant 1984; Solorzano

2004). Gloyd and Conant (1990: 92) discussed additional

Nicaraguan localities that would extend the distribution

northeastward into the southwestern tip of Departamento

Jinotega, but this record is one of several supplied to the

authors by Jaime Villa. Unfortunately, these specimens

were in Villa’s “personal collection that was destroyed

during the earthquake and fire that devastated Managua

beginning on December 23, 1972.” Like Kohler (1999,

2001) , we discounted these records until museum speci-

mens are available from those areas to provide verifica-

tion. The extent of this species’ range, therefore, appar-

ently is greater than 100 km 2 but less than 5,000 km 2 ,

so on the basis of its extent of occurrence it would be

assessed as Endangered. With respect to the number of

localities, three have been reported for Honduras, includ-

ing one based on a photograph in Kohler et al. (2006),

five from Nicaragua (Kohler 2001; a sight record in this

paper), and five from Costa Rica (Conant 1984; Savage

2002) ; most of these localities in Costa Rica, however, fall

within Parque Nacional Santa Rosa, so their total number

could be considered as few as two. Thus the total number

of localities would range from 10 to 13, which techni-

cally would place this species in the Near Threatened cat-

egory, but again historical records (Nicaragua) date back

to 1871 (Gloyd and Conant 1990). As a consequence, this

species would appear to fall in the Vulnerable category.

Furthermore, given the localized distribution of A. how-

ardgloydi in Costa Rica, it is noteworthy that this species

was not reported from the country until 1970 (Bolanos

and Montero 1970).

June 2013 I Volume 7 I Number 1 I e63

Porras et al.

Agkistrodon howardgloydi occurs in disjunct popula-

tions in Honduras, Nicaragua, and Costa Rica, in low-

land dry forest — the most endangered of the major for-

est types in Mesoamerica (Janzen 2004). In Honduras,

nearly all of this forest has been removed from the Pacific

coastal plain. A telling feature in McCranie (2011: table

22) is that of the protected areas in Honduras currently

supporting “some good forest,” not one contains lowland

dry forest. Based on figures from 2001, the departments

of Choluteca and Valle each rank among the top five in

human population density in the country. As noted by

Solorzano et al. (1999), M. Sasa was unsuccessful in

finding this species at several localities in the Golfo de

Fonseca and indicated that most of the locals were un-

aware of its existence. These disturbing reports and ob-

servations suggest that low population densities (or lo-

cal extirpation) might be the trend. Similarly, McCranie

(2011) noted that professional collectors in Choluteca

failed to identify this species from photographs. Also,

three of us (LWP, LDW, GWS) have been unsuccessful

in finding this species on Isla Zacate Grande, in the Golfo

de Fonseca, and on the adjacent mainland.

According to Sunyer and Kohler (2010: 494), similar

population trends prevail in Nicaragua, since A. how-

ardgloydi (as A. bilineatus ) is restricted to lowland dry

forest in the western part of the country, and “this forma-

tion has undergone severe human alteration.” Although

A. howardgloydi apparently occurs in at least three pro-

tected areas, 75% of the protected areas in Nicaragua

“contain less than 50% of their original forest cover...”

(Sunyer and Kohler 2010: 505). The five known locali-

ties for this species in Nicaragua (Kohler 2001; this pa-

per) all are from the most heavily populated region in

the country, an area that likely harbored more extensive

populations of this species in the past.

In Costa Rica, the conservation of A. howardgloydi

is more promising, as most of the restricted range of

✓

this species is located within the Area de Conservacion

Guanacaste. In this region, populations have been re-

ported as “relatively stable and protected” (Solorzano

2004: 622). At Parque Nacional Santa Rosa, for exam-

ple, 21 individuals were obtained for study from 1993

to 1996 (Solorzano et al. 1999). Nonetheless, Sasa et al.

(2010: table 8) indicated that although the distribution of

this species has been reduced by slightly more than 20%

from a potential distribution of 6,883 km 2 , only a little

more than 13% of that reduced distribution (5,465 km 2 )

is located within reserves. Like other venomous snakes,

we can assume that this species is killed on sight in the

87% of the reduced range outside of protected areas. An

important factor in this species’ favor is that the human

population growth rate of Costa Rica (1.2%) is the lowest

in Central America, and that Guanacaste Province, which

encompasses the snake’s entire range in Costa Rica, is

the most sparsely populated of all the provinces.

Although the population of A. howardgloydi in pro-

tected areas of Costa Rica apparently remains stable,

Amphib. Reptile Conserv. | http://amphibian-reptile-conservation.org 063

throughout most of the range populations have been ex-

tirpated (or are nearing extirpation). Thus, in light of the

conservation prospects for A. howardgloydi, we consider

this species as Endangered with the understanding that

a range-wide conservation assessment is required, espe-

cially in Honduras and Nicaragua.

2. Application of the EVS

The conservation status algorithm known as the

Environmental Vulnerability Score (EVS) was developed

by Wilson and McCranie (1992) for use with amphibians

in Honduras and subsequently applied to both amphib-

ians and reptiles in this country (Wilson and McCranie

2004). The EVS was utilized in a broader fashion in most

of the chapters dealing with Central American countries

in Wilson et al. (2010), and in all cases used at the country

level. As noted in the Introduction of this paper, the EVS

for A. bilineatus (sensu lato) in four Central American

countries fell within the upper end of the vulnerability

scale (Wilson and McCranie 2004).

Originally, the EVS algorithm was constructed for

use strictly within Honduras, and thus had limited utility

outside of that country. For example, the scale used for

Honduras was as follows:

1 = widespread in and outside of Honduras

2 = distribution peripheral to Honduras, but wide-

spread elsewhere

3 = distribution restricted to Nuclear Middle America

(exclusive of Honduran endemics)

4 = distribution restricted to Honduras

5 = known only from the vicinity of the type locality

In its original form, four of the five levels of this scale

could not be used outside of Honduras. For the EVS to

have a broader application, therefore, it required recon-

struction and this recently was accomplished for Belize

(Stafford et al. 2010), Nicaragua (Sunyer and Kohler

2010), and Costa Rica (Sasa et al. 2010).

In order to use the EVS measure independent of coun-

try divisions, it requires additional reconstruction, as

follows:

1 = distribution extending from North America (United

States and Canada) to South America

2 = distribution extending from North America to

Mesoamerica or from Mesoamerica to South America

3 = distribution restricted to Mesoamerica

4 = distribution restricted to a single physiographic

region within Mesoamerica

5 = known only from the vicinity of the type locality

The other components of the gauge require only mini-

mal reconstruction. The ecological distribution compo-

nent can be revised as follows:

1 = occurs in eight or more formations

2 = occurs in seven formations

3 = occurs in six formations

4 = occurs in five formations

June 2013 I Volume 7 I Number 1 I e63

Taxonomy and conservation of the common cantil

5 = occurs in four formations

6 = occurs in three formations

7 = occurs in two formations

8 = occurs in one formation

The only modification of this component is that the first

level was changed from “occurs in eight formations” to

“occurs in eight or more formations” (see Wilson and

McCranie 2004). This change appears acceptable, since

very few species in Mesoamerica occupy more than eight

formations (see Wilson and Johnson 2010: table 16).

The component for the degree of human persecution

in reptiles (a different measure was used for amphibians)

is the same as used by Wilson and McCranie (2004), as

follows:

1 = fossorial, usually escape human notice

2 = semifossorial, or nocturnal arboreal or aquatic,

non-venomous and usually non-mimicking, sometimes

escape human notice

3 = terrestrial and/or arboreal or aquatic, generally ig-

nored by humans

4 = terrestrial and/or arboreal or aquatic, thought to be

harmful, might be killed on sight

5 = venomous species or mimics thereof, killed on

sight

6 = commercially or non-commercially exploited for

hides and/or meat and/or eggs

Based on these changes to the EVS, the calculated scores

for the three species of cantils are as follows:

A. bilineatus : 3 + 5 + 5 = 13

A. russeolus: 4 + 6 + 5 = 15

A. howardgloydi : 4 + 8 + 5 = 17

Consequently, the value for A. bilineatus falls at the up-

per end of the medium vulnerability category, and the

values for A. russeolus and A. howardgloydi fall into the

high vulnerability category.

In summary, the IUCN categorizations and EVS val-

ues for these three taxa are as follows: A. bilineatus (Near

Threatened and 13); A. russeolus (Endangered and 15);

and A. howardgloydi (Endangered and 17). Interestingly,

the IUCN has assessed A. taylori as a species of Least

Concern (Lavin et al. 2007), whereas the EVS for this

taxon is reported as 17 (Wilson et al. 2013).

Discussion

We provided a substantive review of the taxonomy and

conservation status of the common cantil (A. bilineatus,

sensu lato). Our taxonomic assessment led us to elevate

the three subspecies of A. bilineatus to full species (A.

bilineatus, A. howardgloydi, and A. russeolus), based on

multiple lines of evidence. Nonetheless, we are not con-

fident that this arrangement necessarily captures the full

diversity of this widely distributed group of pitvipers.

Amphib. Reptile Conserv. | http://amphibian-reptile-conservation.org 064

Accordingly, we identified several regions where ad-

ditional sampling must be accomplished, but overall

we recommend a thorough phylogeographic analysis

employing morphological analyses and the use of both

mtDNA and nuclear (e.g., introns, microsatellites) mark-

ers. Owing largely to the isolation of certain populations,

we suspect that additional species will be discovered

within this complex.

The population of A. bilineatus in southern Sonora

and adjacent southwestern Chihuahua, Mexico, for ex-

ample, occurs in a distinctive habitat (“Sonoran-Sinaloan

transition subtropical dry forest” according to the WWF

[see Garcia 2006]), the color pattern of adults differs

somewhat from that of typical A. bilineatus (Fig. 15), and

a moderate hiatus exists from the closest-known popu-

lation to the south (49 miles [78.8 kilometers] south of

Culiacan, Sinaloa, Mexico; Hardy and McDiarmid 1969;

Campbell and Lamar 2004).

Another example is the insular population on Las Islas

Marias. On this offshore group of islands, two speci-

mens collected in 1881 were reported from the “Tres

Marias” (without naming a specific island), and one

specimen from Isla Maria Grande was collected in 1 897

(Boulenger 1896; Stejneger 1899; see Zweifel 1960).

Interestingly, Gloyd and Conant (1990) indicated that the

cantil with the greatest total length is among these speci-

mens, as well as the A. b. bilineatus (sensu lato) with

the lowest number of subcaudals. Gloyd and Conant

(1990), however, considered this latter specimen as aber-

rant, but commented (p. 69) that “Whether other aberrant

specimens occurred on the islands probably will never

be known, inasmuch as the species may now have been

extirpated from the archipelago.” Casas-Andreu (1992)

indicated the presence of A. bilineatus on other islands

of the Las Islas Marias chain (on Isla San Juanito and

Isla Maria Magdalena). According to G. Casas-Andreu

(pers. comm.), however, these records were not based

on new material, as no cantils were encountered dur-

ing his survey in 1986, but rather they were obtained

from the literature. Inasmuch as no literature citations or

museum numbers for these specimens appear in Casas-

Andreu (1992), our knowledge of the distribution of A.

bilineatus on Las Islas Marias remains sketchy. Although

some areas of “good habitat” were present in the archi-

pelago in 1986 (G. Casas-Andreu, pers. comm.), habitat

destruction, a growing human population (including a

large penal colony), the presence of agricultural camps

and domestic animals, the outright killing of fauna, and

the introduction of rats and feral cats all had become a

significant problem (Casas-Andreu 1992). In 2000, the

archipelago and its surrounding waters were declared an

international protected area (Reserva de la Biosfera Islas

Marfas). In spite of the lack of information on A. bilinea-

tus from these islands, the only reptiles protected under

the Secretarfa del Medio Ambiente y Recursos Naturales

(SEMARNAT) are Crocodylus acutus (special protec-

tion), Iguana iguana (special protection), Ctenosaura

June 2013 I Volume 7 I Number 1 I e63

Porras et al.

Fig. 15. Adult Agkistrodon bilineatus found by Larry Jones and Thomas Skinner in

August of 2005, ca. 12 km NW of Alamos, Sonora, Mexico. This individual later was

released. Photo by James C. Rorabaugh.

Fig. 16. Young cantil from Aldea La Laguna, Nenton, Huehuetenango, Guatemala.

The specific allocation of this population remains uncertain (see Fig. 14).

Photo by Manuel Acevedo.

pectinata (threatened), and Eretmochelys imbricata (in

danger of extinction) (Anonymous 2007). A determina-

tion of the actual distribution and population status of A.

bilineatus on Las Islas Marias, therefore, is a conserva-

tion priority.

The taxonomic status of A. b. lemosespinali , which

tentatively was assigned to A. b. bilineatus by Bryson

and Mendoza-Quijano (2007), remains unresolved.

Known from a single specimen from Palma Sola, in

coastal central Veracruz, Mexico, this area was noted

by Smith and Chizar (2001: 133) as

highly agricultural and located next

to a nuclear power plant regarded by

“many local residents and environ-

mentalists in general as having con-

taminated the surrounding area with

radioactivity.” These authors further

indicated that if “A. b. lemosespinali

ever occurred in that area, it is likely

now to be extinct, or it likely would

have been found [again] long ago.”

Other disjunct populations of

cantils merit a closer examination

at both morphological and molecu-

lar levels, such as those from the

Central Depression of Chiapas and

the headwaters of the Rio Grijalva

that extend into northwestern

Guatemala (Fig. 16), the Rio Chixoy

and Motagua valleys of Guatemala,

as well as isolated populations of

A. russeolus (Gloyd and Conant

1990; Campbell and Lamar 2004;

McCranie 2011).

Assigning protected areas for the

conservation of cantil populations is

not simply a matter of determining

regions that exist within the range

of the three species, as these have

been shown to vary in their level of

protection. Jaramillo et al. (2010:

650) presented a model that could

be used to analyze systems of pro-

tected areas in Mesoamerica, and

based on six requisites concluded

that the system of protected areas

in Panama is impressive due to the

number of areas included and their

collective territory; a detailed ex-

amination of the features, however,

demonstrated that all but one of the

97 areas failed, to some degree, “in

meeting the necessary requirements

for the long-term protection of its

biotic resources.” In Honduras,

McCranie (2011) indicated that, “at

first glance, Honduras appears to have in place a robust

system of protected areas, especially when compared to

nearby countries. However, most of those areas exist on

paper only.” Similarly, Acevedo et al. (2010) stated that,

“the existing system of protected areas in Guatemala is

insufficient to protect the country’s herpetofauna, be-

cause most of the legally designated areas must be con-

sidered as ‘paper parks’.” Essentially the same story can

be told about systems of protected areas in other coun-

tries where cantils occur (see various chapters in Wilson

Amphib. Reptile Conserv. | http://amphibian-reptile-conservation.org 065 June 2013 | Volume 7 | Number 1 | e63

Taxonomy and conservation of the common cantil

et at. 2010), an unfortunate aspect of reality in ongoing

efforts to conserve biodiversity.

Unfortunately, because of the continuing destruction

of natural habitats and the potential for the extirpation of

cantil populations, the answers to some of the aforemen-

tioned questions are on the brink of being lost forever, if

not lost already. This problem is critical, and we view it

as a race against time to generate the necessary informa-

tion that could help set aside protected areas to conserve

disjunct and relictual populations of cantils for posterity.

Conservation Recommendations

Our recommendations for the long-term conservation of

A. bilineatus, A. howardgloydi, A. russeolus , and A. tay-

lori are as follows:

1. In light of the paucity of information regarding the

relative health of populations of these species, it will

be essential to undertake population assessments for

all the cantils at or near localities where they have

been recorded, most critically for A. howardgloydi

and A. russeolus because of their relatively limited

geographic ranges.

2. Once these surveys are completed, a conservation

management plan should be developed to ascertain

if populations of all four species are located within

established protected areas, or if new areas should

be considered. Such a plan is critical to the survival

of cantils, especially since outside of protected areas

these snakes generally are killed on sight or other-

wise threatened by persistent habitat destruction or

degradation.

3. Inasmuch as not all protected areas can be expected to

provide adequate levels of protection to support viable

populations of cantils, long-term population monitor-

ing will be essential.

4. Given the elevation of these taxa to full species,

conservation agencies can now use these vipers as

“flagship species” in efforts to publicize conserva-

tion efforts in their respective countries at all lev-

els of interest and concern, including education and

ecotourism.

5. We recommend the establishment of zoo conserva-

tion (e.g., AZA) and outreach programs, such as those

currently in progress for the venomous Guatemalan

beaded lizard (e.g., www.ircf.org; see Domfnguez-

Vega et al. 2012) and a wide variety of highly en-

dangered anuran species (e.g., www.zooatlanta.org).

Captive assurance colonies might help maximize fu-

ture options for the recovery of wild populations.

Amphib. Reptile Conserv. | http://amphibian-reptile-conservation.org 066

6. One major conclusion of this paper is that our knowl-

edge of the taxonomy and phylogeography of cantils

remains at an elementary level. Thus, as conservation

assessments proceed, it will be important to obtain tis-

sue samples from a sufficiently broad array of popu-

lations to allow for more robust molecular analyses.

Similarly, we need more detailed morphological as-

sessments and more sophisticated levels of analyses,

such as geometric morphometric approaches (Davis

2012 ).

Acknowledgments. — We thank the following peo-

ple for submitting or helping us obtain photographs

for this paper: Manuel Acevedo, Javier Alvarado Dias,

Breck Bartholomew, Tim Burkhardt, Eric Dugan,

Robert Gallardo (La Chorcha Lodge), Javier Ortiz,

James C. Rorabaugh, Alejandro Solorzano, Ireri Suazo-

Ortuno, Javier Sunyer, Robert A. Thomas, R. Wayne

Van Devender, and Kevin Zansler. Additionally, Chris

Mattison graciously provided a photo of Agkistrodon

bilinatus for the cover of this issue. We also are grate-

ful to the following individuals for providing regional

biological information on cantils: Gustavo Casas-Andreu

(Las Islas Marias), Alec Knight (Tamaulipas), Javier

Ortiz (Yucatan), Julian C. Lee (Yucatan Peninsula),

Manuel Acevedo (Guatemala), Ryan Earley and Javier

Sunyer (Nicaragua), and Mahmood Sasa and Alejandro

Solorzano (Costa Rica). Lor other courtesies, we appre-

ciate the efforts and cooperation provided by Vicente

Mata-Silva, Robert A. Thomas, and Josiah H. Townsend.

Lran Platt assisted with image cleanup and the layout of

this paper. The molecular work we discussed was made

possible through the courtesy of Michael Douglas and

Marlis Douglas. Several anonymous reviewers provided

valuable insights that helped to improve this paper. Over

the years, numerous people have accompanied one or

more of the authors into the field in search of cantils,

and we reminisce about the good times spent with Ed

Cassano, the late Roger Conant, W. W. Lamar, James R.

McCranie, John Rindfleish, Alejandro Solorzano, and

Mahmood Sasa. Of these, we are especially indebted to

Roger Conant, for without his encouragement and in-

spiration this paper might never have come to fruition.

Beyond this, we wish to dedicate this paper to this re-

markable man, whose influence has been so broadly felt

in our own lives and among herpetologists far and wide.*

*This paper is part of a special issue of Amphibian & Reptile

Conservation that deals with the herpetofauna of Mexico. In ad-

dition to Dr. Conant ’s seminal work on Agkistrodon (with Dr.

Howard K. Gloyd), readers should be reminded that he also pro-

duced important works on this country’s Nerodia (then Natrix )

and Thamnophis.

June 2013 I Volume 7 I Number 1 I e63

Porras et al.

Literature Cited

Acevedo M, Wilson LD, Cano EM, Vasquez-Almazan

C. 2010. Diversity and conservation status of

the Guatemalan herpetofauna. Pp. 406-435 In:

Conservation of Mesoamerican Amphibians and

Reptiles. Editors, Wilson LD, Townsend JH, Johnson

JD. Eagle Mountain Publishing, LC, Eagle Mountain,

Utah, USA.

Allen ER. 1949. Observations on the feeding habits of

the juvenile cantil. Copeia 1949: 225-226.

Anonymous. 2007. Programa de conservation y manejo

Reserva de la Biosfera Islas Marias. Comision

✓

Nacional de Areas Naturales Protegidas, Secretarfa

de Seguridad Publica. Draft, October 2007. 1-150 pp.

Babb RD, Dugan EA. 2008. Geographic Distribution.

Agkistrodon bilineatus (cantil). Mexico: Sonora.

Herpetological Review 39: 110.

Ball RM, Avise JC. 1992. Mitochondrial DNA

phylogeographic differentiation among avian

populations and the evolutionary significance of

subspecies. The Auk 109: 626-636.

Blair KB, Killebrew FC, Smith HM, Chiszar D. 1997.

Mexican amphibians and reptiles in the West Texas

A & M University Natural History Museum. Bulletin

of the Chicago Herpetological Society 32: 174-177.

Bolanos R, Montero JR. 1970. Agkistrodon bilineatus

Gunther from Costa Rica. Revista de Biologia

Tropical 16: 277-279.

Boulenger GA. 1896. Catalogue of the Snakes in the

British Museum ( Natural History). Volume 3. London,

United Kingdom.

Brooks DR, McLennan DA. 1991. Phylogeny, Ecology,

and Behavior: A Research Program in Comparative

Biology. The University of Chicago Press, Chicago,

Illinois, USA.

Bryson RW Jr., Mendoza-Quijano F. 2007. Cantils of

Hidalgo and Veracruz, Mexico, with comments on

the validity of Agkistrodon bilineatus lemosespinali.

Journal of Herpetology 41: 536-539.

Burbrink FT, Lawson R, Slowinski JB. 2000.

Mitochondrial DNA phylogeography of the polytypic

North American rat snake ( Elaphe obsoleta): a critique

of the subspecies concept. Evolution 54: 2107-2118.

Burchfield PM. 1982. Additions to the natural history

of the crotaline snake Agkistrodon bilineatus taylori.

Journal of Herpetology 16: 376-382.

Burger WL, Robertson WB. 1951. A new subspecies

of the Mexican moccasin, Agkistrodon bilineatus.

University of Kansas Science Bulletin 24: 213-218.

Campbell JA. 1998. Amphibians and Reptiles of Northern

Guatemala, the Yucatan, and Belize. University of

Oklahoma Press, Norman, Oklahoma, USA.

Campbell JA, Lamar WW. 1989. The Venomous Reptiles

of Latin America. Comstock Publishing Associates,

Cornell University Press, Ithaca, New York, USA.

Campbell JA, Lamar WW. 2004. The Venomous Reptiles

of the Western Hemisphere (2 volumes). Comstock

Publishing Associates, Cornell University Press,

Ithaca, New York, USA.

Carpenter CC, Gillingham JC. 1990. Ritualized behavior

in Agkistrodon and allied genera. Pp. 523-531 In:

Snakes of the Agkistrodon Complex: A Monographic

Review. Editors, Gloyd HK, Conant R. Society for the

Study of Amphibians and Reptiles, Ithaca, New York,

USA.

Casas- Andreu G. 1992. Anfibios y reptiles de Las

Islas Marias y otras islas adyacentes a la costa de

Nayarit, Mexico. Aspectos sobre su biogeograffia y

conservacion. Anales del Instituto de Biologia de la

Universidad Nacional Autonomade Mexico (Serie

Zoologfa) 63: 95-112.

Castoe TA, Parkinson CL. 2006. Bayesian mixed models

and the phylogeny of pitvipers (Viperidae: Serpentes).

Molecular Phylogeography 39: 91-110.

Castro-Franco R, Bustos Zagal MG. 2004. Additional

records and range extensions of reptiles from Morelos,

Mexico. Herpetological Review 35: 196-197.

Conant R. 1984. A new subspecies of the pit viper

Agkistrodon bilineatus (Reptilia: Viperidae) from

Central America. Proceedings of the Biological

Society of Washington 97: 135-141.

Conant R. 1992. Comments on the survival status of

members of the Agkistrodon complex. Pp. 29-33

In: Contributions in Herpetology. Editors, Strimple

PE, Strimple JL. Greater Cincinnati Herpetological

Society, Cincinnati, Ohio, USA.

Crasz H. 1986. Report of the Society for Researches on

Native Livestock. Tokyo 11: 65-80.

Davis MA. 2012. Morphometries, Molecular Ecology

and Multivariate Environmental Niche Define the

Evolutionary History of the Western Rattlesnake

(Crotalus viridis) complex. Ph.D. Dissertation,

University of Illinois at Urbana-Champaign, Illinois,

USA.

de Queiroz K. 2007. Species concepts and species

delimitation. Systematic Biology 56: 879-886.

Domfguez-Vega H, Monroy-Vilchis O, Balderas- Valdivia

CJ, Geinger CM, Ariano-Sanchez A. 2012. Predicting

the potential distribution of the beaded lizard and

identification of priority areas for conservation.

Journal for Nature Conservation 20: 247-253.

Donoghue MJ. 1985. A critique of the Biological Species

Concept and recommendations for a phylogenetic

alternative. Bryologist 88: 172-181.

Douglas ME, Douglas MR, Schuett GW, Porras LW,

Holycross AT. 2002. Phylogeography of the western

rattlesnake ( Crotalus viridis) complex, with emphasis

on the Colorado Plateau. Pp. 11-50 In: Biology of the

Vipers. Editors, Schuett GW, Hoggren M, Douglas

ME, Greene HW. Eagle Mountain Publishing, LC,

Eagle Mountain, Utah, USA.

June 2013 I Volume 7 I Number 1 I e63

Amphib. Reptile Conserv. | http://amphibian-reptile-conservation.org

067

Taxonomy and conservation of the common cantil

Douglas ME, Douglas MR, Schuett GW, Porras. LW.

2009. Climate change and evolution of the New World

pitviper genus Agkistrodon (Viperidae). Journal of

Biogeography 36: 1164-1180.

Durrant SD. 1955. In defense of subspecies. Systematic

Zoology 4: 186-190.

Edwards JG. 1954. A new approach to infraspecific

categories. Systematic Zoology 3: 1-20.

Fenwick AM, Greene HW, Parkinson CL. 2011. The

serpent and the egg: Unidirectional evolution of

reproductive mode in vipers? Journal of Zoological

Systematics and Evolutionary Research 50: 59-66.

Garcia A. 2006. Using ecological niche modeling to

identify diversity hotspots for the herpetofauna of

Pacific lowlands and adjacent interior valleys of

Mexico. Biological Conservation 120: 25-46.

Garcia-Grajales J, Buenrostro-Silva A. 2011. Ampliacion

del area de distribucion geografica de Oxybelis

fulgidus (Serpentes: Colubridae) y Agkistrodon

bilineatus (Serpentes: Viperidae) en la planicie costera

central de Oaxaca, Mexico. Acta Zooldgica Mexicana

(n.s.) 27:491-495.

Gloyd HK. 1972. A subspecies of Agkistrodon bilineatus

(Serpentes: Crotalidae) on the Yucatan Peninsula,

Mexico. Proceedings of the Biological Society of

Washington 84: 327-334.

Gloyd HK, Conant R. 1990. Snakes of the Agkistrodon

Complex: A Monographic Review. Society for the

Study of Amphibians and Reptiles, Contributions in

Herpetology, Number 6, Ithaca, New York, USA.

Greene HW, Campbell JA. 1992. The future of pitvipers.

Pp. 421-427 In: Biology of the Pitvipers. Editors,

Campbell JA, Brodie ED Jr. Selva, Tyler, Texas, USA.

Guiher TJ, Burbrink FT. 2008. Demographic and

phylogeographic histories of two venomous North

American snakes of the genus Agkistrodon. Molecular

Phylogenetics and Evolution 48: 543-553.

Gunther A. 1863. Third account of new species of snakes

in the collection of the British Museum. The Annals and

Magazine of Natural History (3 rd Series) 12: 348-365.

Hardy LM, McDiarmid RW. 1969. The amphibians and

reptiles of Sinaloa, Mexico. University of Kansas

Publications, Museum of Natural History 18: 39-252.

Harvey PH, Pagel MD. 1991. The Comparative Method

in Evolutionary Biology. Oxford University Press,

New York, USA.

Hausdorf B. 2011. Progress toward a general species

concept. Evolution 64: 923-931.

Henderson RW. 1978. Notes on Agkistrodon bilineatus

(Reptilia, Serpentes, Viperidae) in Belize. Journal of

Herpetology 12: 412M13.

Herrera N, Henrfquez V, Vaquerano R. 2006. Herpetofauna

del Bosque Seco de El Salvador: nuevos registros de

distribucion. Mesoamericana 19(4): 37-43.

IUCN. 2010. Guidelines for using the IUCN Red List

Categories and Criteria. Version 8.1. Available: www.

redlist.org [Accessed 22 July 2011].

Amphib. Reptile Conserv. | http://amphibian-reptile-conservation.org 068

Janzen DH. 1988. Tropical dry forests: the most

endangered major tropical ecosystem. Pp. 130-137 In:

Biodiversity. Editor, Wilson EO. National Academy

Press, Washington, DC, USA.

Janzen DH. 2004. Ecology of dry-forest wildland insects

in the Area de Conservacion Guanacaste. Pp. 80-96

In: Biodiversity Conservation in Costa Rica: Learning

the Lessons in a Seasonal Dry Forest. Editors, Frankie

GW, Mata A, Vinson SB. University of California

Press, Berkeley, California, USA.

Jaramillo C, Wilson LD, Ibanez R, Jaramillo F. 2010.

The herpetofauna of Panama: distribution and

conservation status. Pp. 604-673 In: Conservation

of Mesoamerican Amphibians and Reptiles. Editors,

Wilson LD, Townsend JH, Johnson JD. Eagle

Mountain Publishing, LC, Eagle Mountain, Utah,

USA.

Johnson JD, Mata-Silva V, Ramfrez-Bautista A. 2010.

Geographic distribution and conservation of the

herpetofauna of southeastern Mexico. Pp. 323-360

In: Conservation of Mesoamerican Amphibians and

Reptiles. Editors, Wilson LD, Townsend JH, Johnson

JD. Eagle Mountain Publishing, LC, Eagle Mountain,

Utah, USA.

Knight A, Densmore LD, Rael ED. 1992. Molecular

systematics of the Agkistrodon complex. Pp. 49-69

In: Biology of the Pitvipers. Editors, Campbell JA,

Brodie ED Jr. Selva, Tyler, Texas, USA.

Kohler G. 1999. The amphibians and reptiles of

Nicaragua: a distributional checklist with keys.

Courier F or s chung sinstitut Senckenberg 213: 1-121.

Kohler G. 2001. Anfibios y Reptiles de Nicaragua.

Herpeton, Verlag Elke Kohler, Offenbach, Germany.

Kohler G. 2008. Reptiles of Central America (2 nd edition).

Herpeton, Offenbach, Germany.

Kohler G, Vesely M, Greenbaum E. 2006. The

Amphibians and Reptiles of El Salvador. Krieger

Publishing Company, Malabar, Florida, USA.

Kraus F, Mink DG, Brown WB. 1996. Crotaline

intergeneric relationships based on mitochondrial

DNA sequence data. Copeia 1996: 763-773.

Lavin-Murcio PA, Lazcano D. 2010. Geographic

distribution and conservation of the herpetofauna of

northern Mexico. Pp. 274-301 In: Conservation of

Mesoamerican Amphibians and Reptiles. Editors,

Wilson LD, Townsend JH, Johnson JD. Eagle

Mountain Publishing, LC, Eagle Mountain, Utah,

USA.

Lavin P, Mendoza-Quijano F, Hammerson GA. 2007.

Agkistrodon taylori. In: IUCN 2012. IUCN Red List

of Threatened Species. Version 2012.2. Available:

www.iucnredlist.org [Accessed: 01 March 2013].

Lee JC. 1996. The Amphibians and Reptiles of the

Yucatan Peninsula. Comstock Publishing Associates,

Cornell University Press, Ithaca, New York, USA.

Lee JC, Hammerson GA. 2007. Agkistrodon bilineatus.

In: IUCN 2012. IUCN Red List of Threatened

June 2013 I Volume 7 I Number 1 I e63

Porras et al.

Species. Version 2012.2. Available: www.iucnredlist.

org [Accessed 20 February 2013].

Lemos-Espinal JA, Smith HM. 2007. Anfibios y Reptiles

del Estado de Chihuahua, Mexico / Amphibians

and Reptiles of the State of Chihuahua, Mexico.

Universidad Nacional Autonoma de Mexico,

Tlalnepantla, Mexico, and Comision Nacional Para el

Conocimiento y Uso de la Biodiversidad (CONABIO),

Mexico, DF, Mexico.

Maddison WP, Maddison DR. 2011. Mesquite: a

modular system for evolutionary analysis. Version

2.75. Available: www.mesquiteproject.org [Accessed

12 March 2013].

Malhotra A, Creer S, Pook CE, Thorpe RS. 2010.

Inclusion of nuclear intron sequence data helps to

identify the Asian sister group of New World pitvipers.

Molecular Phylogenetics and Evolution 54: 172-178.

Mallet J. 1995. A species definition for the Modern

Synthesis. Trends in Ecology & Evolution 10: 294-

299.

Malnate EV. 1990. A review and comparison of

hemipenial structure in the genus Agkistrodon (sensu

lato). Pp. 583-588 In: Snakes of the Agkistrodon

Complex: A Monographic Review. Society for the

Study of Amphibians and Reptiles, Contributions to

Herpetology, Number 6, Ithaca, New York, USA.

Martins EP. 1996. Phytogenies and the Comparative

Method in Animal Behavior. Oxford University Press,

New York, USA.

McCranie JR. 20 1 1 . The Snakes of El onduras: Systematics,

Distribution, and Conservation. Society for the

Study of Amphibians and Reptiles, Contributions to

Herpetology, Volume 26, Ithaca, New York, USA.

McCranie JR, Wilson LD. 2002. The Amphibians of

Honduras. Society for the Study of Amphibians and

Reptiles, Contributions to Herpetology, Volume 19,

Ithaca, New York, USA.

Oatley G, Bowiel RCK, Crowe TM. 2011. The use of

subspecies in the systematics of southern African

white-eyes: historical entities or eco-geographic

variants. Journal of Zoology 284: 21-30.

Padial JM, de la Riva I. 2010. A response to recent

proposals for integrative taxonomy. Biological

Journal of the Einnean Society 101: 747-756.

Parkinson CL. 1999. Molecular systematics and

biogeographical history of pitvipers as determined

by mitochondrial ribosomal DNA sequences. Copeia

1999: 576-586.

Parkinson CL, Moody SM, Ahlquist JE. 1997.

Phylogenetic relationships of the “ Agkistrodon

complex” based on mitochondrial DNA sequence

data. Pp. 63-78 In: Venomous Snakes: Ecology,

Evolution and Snakebite. Editors, Thorpe RS, Wiister

W, Malhotra A. Clarendon Press, Oxford, United

Kingdom.

Parkinson CL, Zamudio KR, Greene HW. 2000.

Phylogeography of the pitviper clade Agkistrodon:

historical ecology, species status, and conservation of

cantils. Molecular Ecology 9: 411-420.

Parkinson CL, Campbell JA, Chippindale P. 2002.

Multigene phylogenetic analysis of pitvipers, with

comments on their biogeography. Pp. 93-110 In:

Biology of the Vipers. Editors, Schuett GW, Hoggren

M, Douglas ME, Greene HW. Eagle Mountain

Publishing, LC, Eagle Mountain, Utah, USA.

Population Reference Bureau. 2010 World Population

Data Sheet. Available: www.prb.org [Accessed: 27

January 2012].

Sasa M, Chaves G, Porras LW. 2010. The Costa

Rican herpetofauna: conservation status and future

perspectives. Pp. 510-603 In: Conservation of

Mesoamerican Amphibians and Reptiles. Editors,

Wilson LD, Townsend JH, Johnson JD. Eagle

Mountain Publishing, LC, Eagle Mountain, Utah,

USA.

Sasa M, Solorzano A. 1995. The reptiles and amphibians

of Santa Rosa National Park, Costa Rica, with

comments about the herpetofauna of xerophytic areas.

Herpetological Natural History 3: 113-125.

Savage JM. 2002. The Amphibians and Reptiles of Costa

Rica: A Herpetofauna between Two Continents,

between Two Seas. The University of Chicago Press,

Chicago, Illinois, USA.

Schwentner M, Timms B V, Richter S . 20 1 1 . An integrative

approach to species delineation incorporating different

species concepts: a case study of Limnadopsis

(Branchiopoda: Spinicaudata). Biological Journal of

the Einnean Society 104: 575-599.

Sibley CG. 1954. The contribution of avian taxonomy [to

a symposium on subspecies and clines]. Systematic

Zoology 3: 105-110, 125.

Smith HM, Chiszar D. 2001. A new subspecies of cantil

( Agkistrodon bilineatus ) from central Veracruz,

Mexico (Reptilia: Serpentes). Bulletin of the Maryland

Herpetological Society 37: 130-136.

Solorzano A. 2004. Serpientes de Costa Rica:

Distribucion, Taxonomia, e Historia Natural / Snakes

of Costa Rica: Distribution, Taxonomy, and Natural

History. Instituto Nacional de Biodiversidad, Santo

Domingo de Heredia, Costa Rica.

Solorzano A, Romero M, Gutierrez JM, Sasa M. 1999.

Venom composition and diet of the cantil Agkistrodon

bilineatus howardgloydi (Serpentes: Viperidae).

Southwestern Naturalist 44: 478-483.

Stafford PJ, Meyer JR. 2000. A Guide to the Reptiles of

Belize. Academic Press, San Diego, California, USA.

Stafford PJ, Walker P, Edgar P, Penn MG. 2010.

Distribution and conservation of the herpetofauna of

Belize. Pp. 370-405 In: Conservation of Mesoamerican

Amphibians and Reptiles. Editors, Wilson LD,

Townsend JH, Johnson JD. Eagle Mountain Publishing,

LC, Eagle Mountain, Utah, USA.

Stejneger L. 1899. Reptiles of the Tres Marias and Isabel

Islands. North American Fauna 14: 63-77 .

June 2013 I Volume 7 I Number 1 I e63

Amphib. Reptile Conserv. | http://amphibian-reptile-conservation.org

069

Strimple P. 1988. Comments on caudal luring in snakes

with observations on this behavior in two subspecies of

cantils, Agkistrodon bilineatus ssp. Notes from Noah,

The Northern Ohio Association of Herpetologists

15(6): 6-10.

Strimple P. 1992. Caudal-luring: a discussion on

definition and application of the term. Pp. 49-54

In: Contributions in Herpetology. Editors, Strimple

PD, Strimple JL. Greater Cincinnati Herpetological

Society, Cincinnati, Ohio, USA.

Sunyer J, Kohler G. 2010. Conservation status of

the herpetofauna of Nicaragua. Pp. 488-509 In:

Conservation of Mesoamerican Amphibians and

Reptiles. Editors, Wilson LD, Townsend JH, Johnson

JD. Eagle Mountain Publishing, LC, Eagle Mountain,

Utah, USA.

Townsend JH, Wilson LD. 2010. Conservation of the

Honduran herpetofauna: issues and imperatives.

Pp. 460-487 In: Conservation of Mesoamerican

Amphibians and Reptiles. Editors, Wilson LD,

Townsend JH, Johnson JD. Eagle Mountain

Publishing, LC, Eagle Mountain, Utah, USA.

Villa JD. 1984. The venomous snakes of Nicaragua: a

synopsis. Contributions in Biology and Geology,

Milwaukee Public Museum 59: 1-41.

Wiley EO. 1978. The evolutionary species concept

reconsidered. Systematic Zoology 27: 17-26.

Wiley EO. 1981. Phylogenetics: The Theory and Practice

of Phylogenetic Systematics. Wiley-Interscience, New

York, USA.

Wiley EO, Mayden RL. 2000. The Evolutionary Species

Concept. Pp. 70-89 In: Species Concepts and

Phylogenetic Theory: A Debate. Editors, Wheeler

QD, Meier R. Columbia University Press, New York,

New York, USA.

Wilson EO, Brown WL. 1953. The subspecies concept

and its taxonomic application. Systematic Zoology 2:

97-111.

Wilson LD, Johnson JD. 2010. Distributional patterns

of the herpetofauna of Mesoamerica, a biodiversity

hotspot. Pp. 30-235 In: Conservation of Mesoamerican

Amphibians and Reptiles. Editors, Wilson LD,

Townsend JH, Johnson JD. Eagle Mountain

Publishing, LC, Eagle Mountain, Utah, USA.

Wilson LD, Mata-Silva V, Johnson JD. 2013. A

conservation reassessment of the reptiles of Mexico

based on the EVS measure. Amphibian & Reptile

Conservation 7(1): 1-47 (e61).

Wilson LD, McCranie JR. 1992. Status of amphibian

populations in Honduras. Unpublished report to the

task force on Declining Amphibian Populations. 14 pp.

Wilson LD, McCranie JR. 2004. The conservation

status of the herpetofauna of Honduras. Amphibian &

Reptile Conservation 3: 6-33.

Wilson LD, Townsend JH, Johnson JD. 2010.

Conservation of Mesoamerican Amphibians and

Reptiles. Editors, Wilson LD, Townsend JH, Johnson

JD. Eagle Mountain Publishing, LC, Eagle Mountain,

Utah, USA.

Zink RM. 2004. The role of subspecies in obscuring avian

biological diversity and misleading conservation

policy. Proceedings of the Royal Society of London B

271: 561-564.

Zweifel RG. 1960. Results of the Puritan-American

Museum of Natural History expedition to western

Mexico. 9. Herpetology of the Tres Marias Islands.

Bulletin of the American Museum of Natural History

119 (article 2): 77-128.

Received: 18 March 2013

Accepted: 24 May 2013

Published: 20 June 2013

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Louis W. Porras is President of Eagle Mountain Publishing, LC, a company that has published Biology of

the Vipers (2002), Biology of the Boas and Pythons (2007), Amphibians, Reptiles, and Turtles in Kansas

(2010), Conservation of Mesoamerican Amphibians and Reptiles (2010), and Amphibians and Reptiles of

San Luis Potosi (2013). For many years Louis served as Vice-President and President of the International

Herpetological Symposium, and during his tenure was instrumental (along with Gordon W. Schuett) in

launching the journal Herpetological Natural History. A native of Costa Rica, Porras has authored or

co-authored over 50 papers in herpetology. During the course of his studies he has traveled extensively

throughout the Bahamas and Latin America. Two taxa, Sphaerodactylus nigropunctatus porrasi, from the

Ragged Islands, and Porthidium porrasi , from Costa Rica, have been named in his honor.

Larry David Wilson is a herpetologist with lengthy experience in Mesoamerica, totaling six collective

years (combined over the past 47). Larry is the senior editor of the recently published Conservation of

Mesoamerican Amphibians and Reptiles and a co-author of seven of its chapters. He retired after 35 years

of service as Professor of Biology at Miami-Dade College in Miami, Florida. Larry is the author or co-

author of more than 290 peer-reviewed papers and books on herpetology, including the 2004 Amphibian &

Reptile Conservation paper entitled “The conservation status of the herpetofauna of Honduras.” His other

books include The Snakes of Honduras, Middle American Herpetology, The Amphibians of Honduras,

Amphibians & Reptiles of the Bay Islands and Cay os Cochinos, Honduras, The Amphibians and Reptiles

of the Honduran Mosquitia, and Guide to the Amphibians & Reptiles ofCusuco National Park, Honduras.

He also served as the Snake Section Editor for the Catalogue of American Amphibians and Reptiles for

33 years. Over his career, Larry has authored or co-authored the descriptions of 69 currently recognized

herpetofaunal species and six species have been named in his honor, including the anuran Craugastor

lauraster and the snakes Cerrophidion wilsoni, Myriopholis wilsoni, and Oxybelis wilsoni.

Gordon W. Schuett is an evolutionary biologist and herpetologist who has conducted extensive research

on reptiles. His work has focused primarily on venomous snakes, but he has also published on turtles,

lizards, and amphibians. His most significant contributions to date have been studies of winner-loser ef-

fects in agonistic encounters, mate competition, mating system theory, hormone cycles and reproduction,

caudal luring and mimicry, long-term sperm storage, and as co-discoverer of facultative parthenogenesis

in non-avian reptiles. He served as chief editor of the peer-reviewed book Biology of the Vipers and

is presently serving as chief editor of an upcoming peer-reviewed book The Rattlesnakes of Arizona

(rattlesnakesofarizona.org). Gordon is a Director and scientific board member of the newly founded non-

profit The Copperhead Institute (copperheadinstitute.org). He was the founding Editor of the journal

Herpetological Natural History. Dr. Schuett is an adjunct professor in the Department of Biology at

Georgia State University.

Randall S. Reiserer is an integrative biologist whose research focuses on understanding the interrelation-

ships among ecology, morphology, and behavior. Within the broad framework of evolutionary biology,

he studies cognition, neuroscience, mimicry, life-history evolution, and the influence of niche dynamics

on patterns of evolutionary change. His primary research centers on reptiles and amphibians, but his

academic interests span all major vertebrate groups. His studies of behavior are varied and range from

caudal luring and thermal behavior in rattlesnakes to learning and memory in transgenic mice. His studies

of caudal luring in snakes established methods for studying visual perception and stimulus control. He

commonly employs phylogenetic comparative methods and statistics to investigate and test evolutionary

patterns and adaptive hypotheses. Dr. Reiserer is an editor of the upcoming peer-reviewed book, The

Rattlesnakes of Arizona.

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June 2013 I Volume 7 I Number 1 I e63

Porras et al.

Appendix 1 . Morphological characters of the subspecies of Agkistrodon bilineatus (ingroup) and two outgroups (A. contortrix and A.piscivorus)

used for character mapping analysis in this study. Unless otherwise indicated, characters are based on adult stages. *Not used in analysis.

Ingroup (cantils)

Agkistrodon bilineatus bilineatus

Upper facial stripe (lateral view): relatively broad and white.

Lower facial stripe (lateral view): relatively broad and continuous with dark pigment below; white.*

Dorsal coloration of adults: very dark brown to black; crossbands usually absent; if present, difficult to distinguish;

pattern composed of small white spots or streaks.

Chin and throat: dark brown or black, with narrow white lines or markings.

Venter: dark brown or black with pale markings.*

Coloration of neonates/juveniles: some shade of brown with crossbands separated by a paler ground color; lateral

edges of crossbands flecked with white.

Tail tip of neonates: bright yellow.

Sexual color dimorphism: absent.

Agkistrodon bilineatus howardgloydi

Upper facial stripe (lateral view): narrow and white; posterior portion often absent in adults.

Lower facial stripe (lateral view): broader than upper stripe, and divided into two components; stripe bordered

below by dark line, followed by pale pigment to lower edge of supralabials; white.*

Dorsal coloration of adults: reddish brown or brown; pattern of dark crossbands contrasts moderately with dorsal

ground color.

Chin and throat: orange yellow, bright orange, or brownish orange with few white spots.

Venter: dark reddish brown.*

Coloration of neonates/juveniles: tan to reddish orange, or reddish, with reddish brown crossbands edged intermit-

tently with white and/or black, especially as they approach venter.

Tail tip of neonates/juveniles: banded with sequential pattern ranging from very dark gray anteriorly to paler gray

toward the tip, with interspaces alternating from pale gray to white.

Sexual color dimorphism: moderate sexual color dimorphism present in sub-adults and adults.

Agkistrodon bilineatus russeolus

Upper facial stripe (lateral view): narrow and white; sometimes intermittent posterior to eye.

Lower facial stripe (lateral view): broader than upper stripe and continuous, with narrow band of dark pigment

below; white.*

Dorsal coloration of adults: pale reddish brown; broad deep reddish brown to brown crossbands separated by paler

areas, and strongly edged irregularly with white; crossbands remain apparent, even in older adults; laterally, centers

of crossbands paler and usually contain one or two dark spots.

Chin and throat: pattern often reduced; small whitish spots or lines evident on a darker background.

Venter: approximately the median third is not patterned.*

Coloration of neonates/juveniles: pattern of brown crossbands with paler brown interspaces; banding intermittently

edged with white; with growth, inner portion of crossbands turns same color as interspaces, thereby developing a

highly fragmented pattern.

Tail tip of neonates/juveniles: pale gray with faint white banding; darker gray tones evident with growth.

Sexual color dimorphism: absent.

Agkistrodon taylori

Upper facial stripe (lateral view): relatively broad and white.

Lower facial stripe (lateral view): broad and continuous, and extends to lower edge of supralabials.

Dorsal coloration of adults: pronounced black crossbands separated by gray, pale brown, or lavender areas that

often contain yellow-brown or orange.*

Chin and throat: bold markings, with white, yellow and or orange elements.

Venter: dark gray or black markings arranged in a somewhat checkerboard pattern.

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Taxonomy and conservation of the common cantil

Coloration of neonates/juveniles: strongly patterned, but with markings like those of adults but less intense.

Tail tip of neonates/juveniles: yellow (rarely, white).

Sexual color dimorphism: present in all age classes; sometimes difficult to detect in older adults that darken.

Outgroups

Agkistrodon piscivorus (outgroup 1)

Upper facial stripe (lateral view): variable in size and appearance; pale but not white.

Lower facial stripe (lateral view): relatively broad and continuous with dark pigment below.*

Dorsal coloration of adults: very dark brown to black; crossbands present in some populations, difficult to distin-

guish; pattern composed of small white spots or streaks.

Chin and throat: pale, cream to white.

Venter: dark brown or black with pale markings.*

Coloration of neonates/juveniles: pale ground color with pronounced bands; strong ontogenetic change

Tail tip of neonates: bright yellow.

Sexual color dimorphism: absent.

Agkistrodon contortrix (outgroup 2)

Upper facial stripe (lateral view): absent.

Lower facial stripe (lateral view): absent.*

Dorsal coloration of adults: light tan ground color; brown crossbands of varying size present.

Chin and throat: tan; typically same as ground color of face and dorsum.

Venter: pale tan with dark tan markings.*

Coloration of neonates/juveniles: ground color pale tan; similar to adults but subdued.

Tail tip of neonates: bright yellow.

Sexual color dimorphism: absent.

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June 2013 I Volume 7 I Number 1 I e63

Dr. Daniel D. Beck (right) with Martin Villa at the Centro Ecologia de Sonora, in Hermosillo, Mexico. Dr. Beck is holding a near-

record length Rio Fuerte beaded lizard ( Heloderma horridum exasperation). Photo by Thomas Wiewandt.

July 2013 | Volume 7 | Number 1 | e67

Amphib. Reptile Conserv. | http://amphibian-reptile-conservation.org

074

mons Attribution-NonCommercial-NoDerivs 3.0 Unported License, which permits unrestricted use for non-com-

mercial and education purposes only provided the original author and source are credited.

Amphibian & Reptile Conservation 7(1): 74-96.

Taxonomic reassessment and conservation status

of the beaded lizard, Heloderma horridum

(Squamata: Helodermatidae)

Randall S. Reiserer, 1 2 Gordon W. Schuett, and 3 Daniel D. Beck

'The Copperhead Institute, P. O. Box 6755, Spartanburg, South Carolina 29304, USA department of Biology and Center for Behavioral Neuro-

science, Georgia State University, 33 Gilmer Street, SE, Unit 8, Atlanta, Georgia, 30303-3088, USA 3 Department of Biological Sciences, Central

Washington University, Ellensburg, Washington 98926, USA

Abstract. — The beaded lizard ( Heloderma horridum) and Gila monster ( H . suspectum) are large,

highly venomous, anguimorph lizards threatened by human persecution, habitat loss and degrada-

tion, and climate change. A recent DNA-based phylogenetic analysis of helodermatids (Douglas et

al. 2010. Molecular Phylogenetics and Evolution 55: 153-167) suggests that the current infraspecific

taxonomy (subspecies) of beaded lizards underestimates their biodiversity, and that species status

for the various subspecies is warranted. Those authors discussed “conservation phylogenetics,”

which incorporates historical genetics in conservation decisions. Here, we reassess the taxonomy

of beaded lizards utilizing the abovementioned molecular analysis, and incorporate morphology by

performing a character mapping analysis. Furthermore, utilizing fossil-calibrated sequence diver-

gence results, we explore beaded lizard diversification against a backdrop of the origin, diversifica-

tion, and expansion of seasonally dry tropical forests (SDTFs) in Mexico and Guatemala. These for-

ests are the primary biomes occupied by beaded lizards, and in Mesoamerica most are considered

threatened, endangered, or extirpated. Pair-wise net sequence divergence (%) values were greatest

between H. h. charlesbogerti and H. h. exasperatum (9.8%), and least between H. h. alvarezi and H. h.

charlesbogerti (1%). The former clade represents populations that are widely separated in distribu-

tion (eastern Guatemala vs. southern Sonora, Mexico), whereas in the latter clade the populations

are much closer (eastern Guatemala vs. Chiapas, Mexico). The nominate subspecies ( Heloderma h.

horridum) differed from the other subspecies of H. horridum at 5.4% to 7.1%. After diverging from a

most-recent common ancestor ~35 mya in the Late Eocene, subsequent diversification (cladogen-

esis) of beaded lizards occurred during the late Miocene (9.71 mya), followed by a lengthy stasis of

up to 5 my, and further cladogenesis extended into the Pliocene and Pleistocene. In both beaded

lizards and SDTFs, the tempo of evolution and diversification was uneven, and their current distribu-

tions are fragmented. Based on multiple lines of evidence, including a review of the use of trinomi-

als in taxonomy, we elevate the four subspecies of beaded lizards to full species: Heloderma alvarezi

(Chiapan beaded lizard), H. charlesbogerti (Guatemalan beaded lizard), H. exasperatum Rio Fuerte

beaded lizard), and H. horridum (Mexican beaded lizard), with no changes in their vernacular names.

Finally, we propose a series of research programs and conservation recommendations.

Key words. mtDNA, ATPase, nuclear genes, character mapping, genomics, seasonally dry tropical forests, reptiles

Resumen. — El escorpion ( Heloderma horridum) y el monstruo de Gila (H. suspectum) son lagartijas

grandes, anguimorfas, y muy venenosas que estan sufriendo diversas amenazas como resultado de

la persecucion humana, degradacion y perdida del habitat y el cambio climatico global. Un analisis

filogenetico reciente basado en ADN de este grupo (Douglas et al. 2010. Molecular Phylogenetics

and Evolution 55: 153-167) sugiere que la actual taxonomia intraespecifica (subespecies) del es-

corpion esta subestimando la diversidad biologica, y el reconocimiento de especies es justificable.

Estos autores discuten la utilidad del enfoque denominado “conservacion filogenetica”, que hace

hincapie en la incorporacion de la genetica historica en las decisiones de conservacion. En este

estudio, reevaluamos la taxonomia del escorpion utilizando el analisis molecular antes mencionado

e incorporamos la morfologia en un analisis de mapeo de caracteres. Asi mismo, con los resultados

de la secuencia de divergencia calibrada con fosiles, se explora la diversificacion del escorpion en

forma yuxtapuesta al origen, la diversificacion y la expansion de los bosques tropicales estacional-

mente secos (SDTFs) en Mexico y Guatemala. Estos bosques son los principales biomas ocupados

por los escorpiones, y en Mesoamerica la mayoria son considerados amenazados, en peligro o

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075

Reiserer et al.

extirpados. Los valores de la secuencia de divergencia neta por pares (%) fueron mayores entre H.

h. charlesbogerti y H. h. exasperatum (9,8%) y menores entre H. h. alvarezi y H. h. charlesbogerti

(1%). El primer grupo representa a poblaciones que estan muy distantes una de la otra en su distri-

bucion (este de Guatemala vs. sur de Sonora, Mexico), mientras que las poblaciones en el segundo

grupo estan mucho mas relacionadas (este de Guatemala vs. Chiapas, Mexico). La subespecie de-

nominada (Heloderma h. horridum) difirio de las otras subespecies de H. horridum entre un 5,4% a

7,1%. Despues de la separacion de un ancestro comun mas reciente, ~35 mda a finales del Eoceno,

ocurrio una diversificacion (cladogenesis) posterior de Heloderma a finales del Mioceno tardfo (9,71

mda), seguida de un estancamiento prolongado de hasta 5 mda, con una cladogenesis posterior

que se extendio hasta el Plioceno y Pleistoceno. En ambos grupos, escorpiones y bosques tropi-

cales estacionalmente secos, los procesos de evolucion y diversificacion fueron desiguales, y su

distribucion fue fragmentada. Hoy en dia, el escorpion esta distribuido de manera irregular a lo

largo de su amplio rango geografico. Basandonos en varias lineas de evidencia, incluyendo una re-

vision del uso de trinomios taxonomicos, elevamos las cuatro subespecies del escorpion al nivel de

especie: Heloderma alvarezi (escorpion de Chiapas), H. charlesbogerti (escorpion Guatemalteco),

H. exasperatum (escorpion del Rio Fuerte), y H. horridum (escorpion Mexicano), sin cambios en los

nombres vernaculos. Por ultimo, proponemos una serie de programas de investigacion y recomen-

daciones para su conservacion.

Palabras claves. ADNmt, ATPasas, genes nucleares, mapeo de caracteres, genomica, bosque tropical estacionalmente

seco, reptiles

Citation: Reiserer RS, Schuett GW, Beck DD. 2013. Taxonomic reassessment and conservation status of the beaded lizard, Heloderma horridum

(Squamata: Helodermatidae). Amphibian & Reptile Conservation 7(1): 74-96 (e67).

The century-long debate over the meaning and utility of

the subspecies concept has produced spirited print but

only superficial consensus. I suggest that genuine con-

sensus about subspecies is an impossible goal ... the sub-

species concept itself is simply too heterogeneous to be

classified as strict science.

Fitzpatrick 2010: 54.

Introduction

The beaded lizard ( Heloderma horridum) is a large, high-

ly venomous, anguimorph (Helodermatidae) squamate

with a fragmented distribution in Mesoamerica that ex-

tends from northwestern Mexico (Sonora, Chihuahua) to

eastern Guatemala (Bogert and Martin del Campo 1956;

Campbell and Vannini 1988; Campbell and Lamar 2004;

Beck 2005; Beaman et al. 2006; Anzueto and Campbell

2010; Wilson et al. 2010, 2013; Dominguez- Vega et

al. 2012). Among the reptilian fauna of this region, the

beaded lizard (in Spanish, known as the “escorpion”) is

well known to local inhabitants, yet its natural history

is surrounded by mystery, notoriety and misconception.

Consequently, it is frequently slaughtered when encoun-

tered (Beck 2005).

Adding to this anthropogenic pressure, beaded lizard

populations, with rare exceptions (Lemos-Espinal et al.

2003; Monroy-Vilchis et al. 2005), occur primarily in

seasonally dry tropical forests, SDTFs (Campbell and

Lamar 2004; Beck 2005; Campbell and Vannini 1988;

Dominguez- Vega et al. 2012), the most endangered

biome in Mesoamerica owing to persistent deforesta-

tion for agriculture, cattle ranching, and a burgeoning

human population (Janzen 1988; Myers et al. 2000; Trejo

and Dirzo 2000; Hoekstra et al. 2005; Miles et al. 2006;

Stoner and Sanchez- Azofeifa, 2009; Williams-Linera

and Lorea 2009; Beck 2005; Pennington et al. 2006;

Wilson et al. 2010, 2013; Dirzo et al. 2011; De-Nova et

al. 2012; Dominguez- Vega et al. 2012; Golicher et al.

2012). Furthermore, drought and fires escalate the above

threats (Beck 2005; Miles et al. 2006), and recent predic-

tive models of climate change show that the persistence

of SDTFs in this region is highly dubious (Trejo and

Dirzo 2000; Miles et al. 2006; Golicher et al. 2012).

Despite its large size and charismatic nature, our

knowledge of the ecology, geographical distribution,

and status of populations of H. horridum remains lim-

ited (Beck and Lowe 1991; Beck 2005; Ariano- Sanchez

2006; Douglas et al. 2010; Domiguez-Vega et al. 2012).

Furthermore, based on multiple lines of evidence, a taxo-

nomic reevaluation of this group of lizards is long over-

due (Beck 2005; Douglas et al. 2010).

Here, we continue the dialogue concerning the infra-

specifc (subspecific) taxonomy and conservation status

of beaded lizards. We reviewed recent publications by

Beck (2005) and Dominguez-Vega et al. (2012), and aug-

ment their conclusions based on personal (DDB) field re-

search in Mexico. We reassess the taxonomic status of

the populations of H. horridum using morphology, bio-

geography, and a recent molecular-based (mtDNA,

nDNA) analysis conducted by Douglas et al. (2010).

Although Douglas et al. (2010) commented on the mo-

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Taxonomy and conservation of beaded lizards

lecular diversity of Heloderma, especially in H. horri-

dum, they did not provide explicit taxonomic changes.

In this paper, therefore, we reevaluate and expand upon

their conclusions. To gain insights into phenotypic (mor-

phological) evolution of extant Heloderma , with em-

phasis on H. horridum, we conduct a character mapping

analysis (Brooks and McLennan 1991; Harvey and Pagel

1991; Martins 1996; Maddison and Maddison 2011), uti-

lizing the phylogenetic information (trees) recovered by

Douglas et al. (2010).

Overview of Morphology and Molecules

in the genus Heloderma

1. Morphological assessment

Published over half a century ago, Bogert and Martin del

Campo’s (1956) detailed and expansive monograph of

extant and fossil helodermatid lizards remains the defini-

tive morphological reference (reviewed in Campbell and

Lamar, 2004; Beck, 2005), and it contains the diagno-

ses and descriptions of two new subspecies (. Heloderma

horridum alvarezi and H. h. exasperatum). Thirty-two

years later, Campbell and Vannini (1988) described a

new subspecies (H. h. charlesbogerti ), from the Rio Mo-

tagua Valley in eastern Guatemala, in honor of Charles

Bogert’ s pioneering work on these lizards. With few ex-

ceptions, such as Conrad et al. (2010) and Gauthier et al.

(2012), who examined higher-level relationships of the

Helodermatidae and other anguimorphs, a modern phy-

logeographic analysis of morphological diversity for ex-

tant helodermatids is lacking. However, as we illustrate

in our character mapping analysis, the morphological

characters used by Bogert and Martin del Campo (1956)

in diagnosing and describing the subspecies of beaded

lizards, though somewhat incomplete, remains useful in

analyzing phenotypic variation.

2. Diagnosis, description, and distribution

of Heloderma horridum

Diagnosis and description . — Bogert and Martin del

Campo (1956) and Campbell and Vannini (1988) pro-

vided diagnoses and descriptions of the subspecies of

Heloderma horridum. Recent information on the biol-

ogy, systematics, and taxonomy of H. horridum and H.

suspectum is summarized and critiqued by Campbell and

Lamar (2004) and Beck (2005), and Beaman et al. (2006)

provided a literature reference summary of the Heloder-

matidae. Presently, four subspecies of H. horridum are

recognized (Figs. 1-5).

Mexican beaded lizard: H. h. horridum (Wiegmann

1829)

Rio Fuerte beaded lizard: H. h. exasperatum Bogert

and Martin del Campo 1956

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Chiapan beaded lizard: H. h. alvarezi Bogert and Mar-

tin del Campo 1956

Guatemalan beaded lizard: H. h. charlesbogerti

Campbell and Vannini 1988

The four subspecies of H. horridum were diagnosed

and described on the basis of scutellation, color pattern,

and geographical distribution, and we refer the reader to

the aforementioned works for detailed descriptions and

taxonomic keys. The characters used by Bogert and Mar-

tin del Campo (1956) and Campbell and Vannini (1988)

to diagnose the subspecies have been reevaluated as to

their stability, albeit informally (Campbell and Lamar

2004; Beck 2005). Poe and Wiens (2000) and Douglas

et al. (2007) discussed the problem of character stabil-

ity in phylogenetic analyses. Kraus (1988), for example,

commented that reasonable evidence for character stabil-

ity, and thus its usefulness as a shared-derived character

(apomorphy), was the occurrence of a discrete trait in

adults at a frequency of 80% or greater. In our character

mapping analysis using published morphological char-

acters (discussed below), character stability was a major

assumption. Consequently, further research is warranted

for substantiation.

Geographic distribution . — The geographic distribu-

tion of Heloderma horridum extends from southern So-

nora and adjacent western Chihuahua, in Mexico, south-

ward to eastern and southern Guatemala (Campbell and

Lamar 2004; Beck 2005; Anzueto and Campbell 2010;

Domiguez-Vega et al. 2012).

The Rio Fuerte Beaded Lizard (H. h. exasperatum) in-

habits the foothills of the Sierra Madre Occidental, with-

in the drainage basins of the Rio Mayo and Rio Fuerte of

the Sonoran-Sinaloan transition subtropical dry forest in

southern Sonora, extreme western Chihuahua, and north-

ern Sinaloa (Campbell and Lamar 2004; Beck 2005). Its

distribution closely matches the fingers of SDTFs within

this region, but it has also been encountered in pine-oak

forest at 1,400 m near Alamos, Sonora (Schwalbe and

Lowe 2000). Bogert and Martin del Campo (1956) com-

mented that as far as their records indicated, a consider-

able hiatus existed between the distribution of H. h. exas-

peratum (to the north) and H. h. horridum (to the south),

but owing to the narrow contact between the supranasal

and postnasal in H. h. horridum from Sinaloa, intergra-

dation might be found in populations north of Mazatlan.

Based on this information, Beck (2005: 24) stated, “...in

tropical dry forest habitats north of Mazatlan, Sinaloa, H.

h. exasperatum likely intergrades with H. h. horridum .”

Definitive data on intergradation remains unreported,

however, and published distribution maps have incorpo-

rated that assumption (e.g., Campbell and Lamar 2004;

Beck 2005). Campbell and Lamar (2004, p. 104) show

a single example of H. suspectum from El Dorado in

west-central Sinaloa, Mexico (deposited in the American

Museum of Natural History [90786]), a locality 280 km

south from northern records in Rio del Fuerte, Sinaloa.

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Reiserer et al.

Fig. 1. A. Adult Rio Fuerte bended lizaid ( Heloderma h o f' fid it m exasperatum ) in a defensive display (Alamos, Sonoia). B. Adult

Rio Fuerte beaded lizard raiding a bird nest (Alamos, Sonora). Photos by Thomas Wiewandt.

Fig. 2. Adult Mexican beaded lizard ( H . h. horridum ) observed on 11 July 2011 at Emiliano Zapata, municipality of La Huerta,

coastal Jalisco, Mexico. Photo by Javier Alvarado.

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Fig. 3. Adult Chiapan beaded lizard ( Heloclerma horridum alvarezi ) from Sumidero Canyon in the Rio Grijalva Valley, east of

Tuxtla Gutierrez, Chiapas, Mexico. Photo by Thomas Wiewandt.

Fig. 4. Adult Guatemalan beaded lizard ( Heloderma horridum charlesbogerti ) from the Motagua Valley, Guatemala.

Photo by Daniel Ariano-Sdnchez.

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Reiserer et al.

Owing to this unusual location, we suggest a re-examina-

tion of this museum specimen to verify its identity. Neo-

nates and juveniles of H. h. exasperatum resemble adults

in color pattern (Fig. 5a), but they show greater contrast

(i.e., a pale yellow to nearly white pattern on a ground

color of brownish-black). Also, their color pattern can be

distinguished from that of adults (e.g., no yellow speck-

ling between the tail bands), and an ontogenetic increase

in yellow pigment occurs (Bogert and Martin del Campo

1956; Beck 2005).

The Mexican beaded lizard ( H . h. horridum ), the

subspecies with the most extensive distribution, occurs

primarily in dry forest habitats from southern Sinaloa

southward to Oaxaca, including the states of Jalisco,

Nayarit, Colima, Michoacan, and Guerrero, and inland

into the states of Mexico and Morelos (Campbell and

Lamar 2004; Beck 2005). Monroy-Vilchis et al. (2005)

Fig. 5. A. Juvenile Heloderma horridum exasperatum (in situ,

/

Alamos, Sonora, Mexico). Photo by Stephanie Meyer.

B. Neonate Heloderma h. horridum (wild-collected July 2011,

Chamela, Jalisco). Photo by Kerry Holcomb.

C. Neonate Heloderma horridum alvarezi (Rio Lagartero

Depression, extreme western Guatemala).

Photo by Quetzal Dwyer.

D. Neonate Heloderma horridum charlesbogerti (hatched at

Zoo Atlanta in late 2012). Photo by David Brothers, courtesy

of Zoo Atlanta.

recorded an observation of this taxon at mid eleva-

tions (e.g., 1861 m) in pine-oak woodlands in the state

s

of Mexico. Campbell and Vannini (1988), citing Alva-

rez del Toro (1983), indicated the probability of areas

of intergradation between H. h. horridum and H. h. al-

varezi , in the area between the Isthmus of Tehuantepec

s

and Cintalapa, Chiapas. Nonetheless, Alvarez del Toro

(1983) stated that individuals of beaded lizards with yel-

low markings (a coloration character present in H. h.

horridum ) are found in the region from Cintalapa to the

Isthmus of Tehuantepec, as well as in dry areas along the

coast from Arriaga (near the Isthmus of Tehuantepec) to

Huixtla (near the Guatemalan border). Literature infor-

mation on intergradation between these two subspecies

is inconclusive and, therefore, will require further inves-

tigation. Neonates and juveniles of H. h. horridum , like

those of H. h. exasperatum , resemble adults in color pat-

tern (Fig. 5b), but their color contrast is greater (Bogert

and Martin del Campo 1956; Beck 2005).

The Chiapan beaded lizard ( H . h. alvarezi ) inhab-

its dry forests in the Central Depression (Rio Grijalva

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Taxonomy and conservation of beaded lizards

Depression) of central Chiapas and the Rio Lagartero

Depression in extreme western Guatemala (Campbell

and Lamar 2004; Beck 2005; Johnson et al. 2010; Wil-

son et al. 2010: p. 435). This taxon is unique among the

subspecies in that it undergoes an ontogenetic increase

in melanism, whereby it tends to lose the juvenile color

pattern (Bogert and Martin del Campo 1956; Beck 2005).

Neonates and juveniles often are distinctly marked with

yellow spots and bands, including on the tail (Fig. 5c),

whereas the color pattern of adults gradually transforms

to an almost uniform dark brown or gray. Black individu-

als, however, are uncommon. Yellow banding on the tail,

a characteristic typical of the other subspecies of beaded

lizards, (Fig. 2), is essentially absent in adults (Bogert

and Martin del Campo 1956; Beck 2005).

The Guatemalan beaded lizard ( H . h. charlesbogerti )

inhabits the Rio Motagua Valley, in the Atlantic versant

of eastern Guatemala (Campbell and Vannini 1988). Re-

cently, however, Anzueto and Campbell (2010) reported

three specimens from two disjunct populations on the

Pacific versant of Guatemala, to the southwest of the

Motagua Valley. Neonates resemble adults in color pat-

tern, though they tend to be paler (Fig. 5d).

In summary, the distribution of H. horridum is frag-

mented throughout its extensive range and corresponds

closely with the patchy distribution of SDTFs in Mexico

and Guatemala (Beck 2005; Miles et al. 2006; Domin-

guez- Vega et al. 2012). The distribution of the Guate-

malan beaded lizard ( H . h. charlesbogerti ) is distinctly

allopatric (Campbell and Vannini 1988; Beck 2005;

Ariano-Sanchez 2006; Anzueto and Campbell 2010).

3. Molecular assessment

Douglas et al. (2010) provided the first detailed molec-

ular-based (mtDNA, nDNA) analysis of the phylogeo-

graphic diversity of helodermatid lizards, which is avail-

able at www.cnah.org/cnah_pdf.asp. Two authors (GWS,

DDB) of this paper were co-authors. Specifically, Doug-

las et al. (2010) used a “conservation phylogenetics”

approach (Avise 2005, 2008; Avise et al. 2008), which

combines and emphasizes the principles and approaches

of genetics and phylogeography and how they can be ap-

plied to describe and interpret biodiversity.

Methods . — Douglas et al. (2010) sampled 135 locality-

specific individuals of Heloderma (48 H. horridum , 87 H.

suspectum) from throughout their range (their ingroup).

The outgroup taxa included multiple lineages of lizards

and snakes, with an emphasis on anguimorphs. Based on

both morphological and DNA-based analyses, all author-

ities have recognized the extant helodermatid lizards as

monotypic (a single genus, Heloderma ), and as members

of a larger monophyletic assemblage of lizards termed

the Anguimorpha (Pregill et al. 1986; Estes et al. 1988;

Townsend et al. 2004; Wiens et al. 2010, 2012; Gauthier

et al. 2012). This lineage includes the well-known va-

ranids ( Varanus ), alligator lizards and their relatives

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(Anguidae), as well as such relatively obscure taxa as the

Old World Lanthanotidae ( Lanthanotus ) and Shinisauri-

dae ( Shinisaurus ), and the New World Xenosauridae (Xe-

nosaurus). The mtDNA analyses in Douglas et al. (2010)

were rooted with the tuatara ( Sphenodon punctatus), and

Bayesian and maximum parsimony (MP) analyses were

conducted using Mr. Bayes (Hulsenbeck and Rohnquist

2001 ).

Douglas et al. (2010) used sequence data from both mi-

tochondrial (mt) DNA and nuclear (n) DNA as molecular

markers in their phylogenetic analyses. Specifically, they

discussed reasons for selecting mtDNA regions ATPase

8 and 6, and the nDNA introns alpha-enolase (ENOL)

and ornithine decarboxylase (OD). The utility of com-

bining mt- and nDNAs (supertree) in recovering phylo-

genetic signals has been discussed (Douglas et al. 2007,

2010), yet each of these markers and the procedure of

combining sequence data have both benefits and pitfalls

(Wiens 2008; Castoe et al. 2009). Long-branch attraction

and convergence, for example, can result in misleading

relationships (Bergsten 2005; Wiens 2008; Castoe et al.

2009). The tools for detecting and potentially correcting

these problems have been discussed (e.g., Castoe et al.

2009; Assis and Rieppel 2011).

Results and discussion. — Douglas et al. (2010) recov-

ered the genus Heloderma as monophyletic (Heloder-

matidae), with H. horridum and H. suspectum as sister

taxa. In a partitioned Bayesian analysis of mtDNA, He-

lodermatidae was recovered as sister to the anguimorph

clade {Shinisaurus {Abronia + Elgaria )), which in turn

was sister to the clade Lanthanotus + Varanus. Recent

molecular studies of squamates by Wiens et al. (2012, see

references therein) recovered a similar topology to that

of Douglas et al. (2010). However, an extensive morpho-

logical analysis by Gauthier et al. (2012) supported a tra-

ditional topology of Heloderma as sister to varanids and

Lanthanotus borneensis (see Estes et al. 1986; Pregill et

al. 1988). In Douglas et al. (2010), a partitioned Bayes-

ian analysis of the nuclear marker alpha-enolase (intron 8

and exon 8 and 9), however, recovered Heloderma as sis-

ter to a monophyletic Varanus. Using a combined analy-

sis of morphology (extant and fossil data), mitochondrial,

and nuclear markers, Lee (2009) recovered Varanidae as

sister to the clade Helodermatidae + Anguidae. In a com-

bined approach, Wiens et al. (2010) recovered results that

were similar to those of Lee (2009). A recent DNA-based

analysis of Squamata by Pyron et al. (2013) examined

4151 species (lizards and snakes), and they recovered

Helodermatidae as sister to the clade Anniellidae + An-

guidae. Moreover, they recovered the clade Varanidae +

Lanthanotidae as sister to Shinisauridae.

How do systematists deal with this type of incon-

gruity (discordance) in studies that use different types

(e.g., morphology vs. molecular) of phylogenetic mark-

ers? Recently, Assis and Rieppel (2011) and Losos et al.

(2012) discussed the common occurrence of discordance

between molecular and morphological phylogenetic

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Reiserer et al.

analyses. Specifically, with respect to discordance, As-

sis and Rieppel (2011) stated that, “...the issue is not to

simply let the molecular signal override the morphologi-

cal one. The issue instead is to make empirical evidence

scientific by trying to find out why such contrastive

signals are obtained in the first place.” We concur with

their opinions, and thus further research is warranted to

resolve such conflicts in the phylogeny of anguimorph

squamates.

Relationships among the four subspecies of H. hor-

ridum recovered in the analysis by Douglas et al. (2010,

p. 158-159, fig. 3a, b) are depicted in Fig. 6. This topol-

ogy was derived from a partitioned Bayesian analysis of

the mtDNA regions ATPase 8 and 6. The Gila monster

(H. suspectum ) was the immediate outgroup. Two sets of

sister pairs of beaded lizards were recovered: H. h. exas-

peratum (HHE) + H. h. horridum (HHH), and H. h. al-

varezi (HHA) + H. h. charlesbogerti (HHC). The current

subspecific designations for H. horridum were robustly

supported (concordant) by these genetic analyses. Un-

like results obtained for Gila monsters ( H . suspectum ),

haplotype and genotype data for H. horridum were both

diverse and highly concordant with the designated sub-

species and their respective geographic distributions.

Douglas et al. (2010) generated pair-wise net sequence

divergence (%) values based on their recovered relation-

ships (Table 1, Fig. 6). The greatest divergence was be-

tween HHE and HHC (9.8%), and the least between HHA

and HHC (1%). The former pair represents populations

widely separated in distribution (southern Sonora, Mex-

ico vs. eastern Guatemala), whereas the latter are much

more closely distributed (Chiapas, Mexico vs. eastern

Guatemala). The nominate subspecies ( Heloderma h.

horridum) differed from the other three subspecies of

beaded lizards, from 5.4% to 7.1%.

Table 1. Pair-wise net sequence divergence (%) values between

the four subspecies of the beaded lizard ( Heloderma horridum )

derived from a partitioned Bayesian analysis of the mtDNA re-

gions ATPase 8 and 6 (modified from Douglas et al. 2010, pp.

157-159, 163; fig. 3a, b, tables 1 and 3). Values in parentheses

denote evolutionary divergence times, which represent mean

age. Mean age is the time in millions of years (mya) since the

most-recent common ancestor (tree node) and is provided for

the sister clades HHE-HHH and HHA-HHC (Fig. 6). Beaded

lizards and Gila monsters (H. suspectum ) are hypothesized

to have diverged from a most-recent common ancestor in the

late Eocene ~35 mya (Douglas et al. 2010, p. 163). Percent se-

quence divergence was greatest for HHC-HHE, and was lowest

for HHA-HHC. See text for further details.

HHA

HHC

HHE

HHH

HHA

HHC

HHE

1% (3.02)

9.3%

9.8%

HHH

5.4%

6.2%

7.1% (4.42)

—

HHA = H. h. alvarezi', HHC = H. h. charlesbogerti ; HHE = H. h. exas-

peratum; HHH = H. h. horridum.

Fig. 6. Character mapping analysis. Tree topology and node dates based on Douglas et al. (2010). Morphological characters (Table

2) were mapped via parsimony and outgroup methods using the software program Mesquite (Maddison and Maddison 2011). Node

1 = Late Eocene (—35 million years ago, mya); Node 2 = 9.71 mya; Node 3 = 4.42 mya; and Node 4 = 3.02 mya (see Table 1). See

text for details of the analysis.

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Table 2. Morphological characters used for the character mapping analysis (see Table 1, Fig. 6). See text for details.

Character

State

Designation

Tail length

41-55% of snout-to-vent length

A0

> 65% of snout-to-vent length

A1

Number of caudal vertebrae

25-28

B0

40

B1

Number of transverse rows of ventromedial

absent

CO

caudal scales (vent to tail tip) greater than 62

present

Cl

Usually one pair of enlarged preanal scales

present

DO

absent

D1

First pair of infralabials usually in contact with

present

E0

chin shields

absent

El

Number of maxillary teeth

8-9

F0

6-7

FI

Upper posterior process of splenial bone

overlaps inner surface of coronoid

GO

does not overlap coronoid

G1

Number of black tail bands (including black

4-5

HO

terminus on tail of juveniles)

6-7

HI

Adult total length

< 570 mm

10

> 600 mm

11

Tongue color

black or nearly so

JO

pink

J1

Supranasal-postnasal association

in contact

KO

separated by first canthal

K1

Association of second supralabial and

in contact

LO

prenasal/nasal plates

separated by lorilabial

LI

Shape of mental scute

shield-shaped (elongate and triangular)

MO

wedge-shaped (twice as long as wide)

Ml

Dominant adult dorsal coloration

orange, pink

NO

black or dark brown

N1

yellow

N2

Adult dorsal yellow spotting

absent

OO

extremely low

01

low

02

med

03

high

04

Mental scute

scalloped edges absent

PO

moderately scalloped edges

PI

Enlarged preanal scutes in some females

absent

QO

present

Qi

Ontogenetic melanism

absent

RO

present

R1

Spots on tail in adults

absent

SO

present

SI

Bands on tail

black

TO

yellow

T1

absent

T2

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Reiserer et al.

4. Character mapping analysis

A character mapping analysis (CMA) is one of several ro-

bust tools used in comparative biology to comprehend the

distribution of traits (e.g., morphology), often by explic-

itly utilizing molecular phylogenetic information (Brooks

and McLennan 1991; Harvey and Pagel 1991; Martins

1996; Freeman and Herron 2004; Maddison and Mad-

dison 2011; for a critique, see Assis and Rieppel 2011).

Specifically, the CMA aims to provide insights to the ori-

gin, frequency, and distribution of selected traits formally

expressed onto a tree (e.g., Schuett et al. 2001, 2009; Fen-

wick et al. 2011). These procedures also are potentially

useful in disentangling homology from homoplasy (Free-

man and Herron 2004). Furthermore, the CMA provides

a framework for testing hypotheses of adaptive evolution

and the identification of species (Harvey and Pagel 1991;

Futuyma 1998; Freeman and Herron 2004; Schuett et al.

2001, 2009; Maddison and Maddison 2011). However,

CMA does not replace a strict phylogenetic analysis of

morphological traits (Assis and Rieppel 2011).

Here, we used character mapping to investigate the

morphological traits of the four subspecies of H. horri-

dum, to gain insights on the distribution, divergence, and

homology (e.g., shared-derived traits, such as possible

autapomorphies) of these traits.

Methods . — We used published morphological data on

Heloderma (Bogert and Martin del Campo 1956; Camp-

bell and Vannini 1988; Campbell and Lamar 2004; Beck

2005) and selected 20 morphological characters for the

CMA (Table 2). All characters were coded as binary (i.e.,

0, 1) or multi-state (e.g., 0, 1, 2). Non-discrete multi-state

characters (e.g., color pattern) were ordered from low-

est to highest values. Character polarity was established

by using H. suspectum as the outgroup. The CMA traced

each character independently by using the outgroup anal-

ysis and parsimony procedures in Mesquite (Maddison

and Maddison 2011), and we combined the individual

results onto a global tree.

Results and discussion . — The CMA results (Fig. 6)

show that multiple morphological traits are putative apo-

morphies or autapomorphies (traits unique to a single

taxon) for the various H. horridum clades (subspecies)

delimited in the molecular tree recovered by Douglas et

al. (2010). Although we had a priori knowledge of spe-

cific and unique traits (presumptive autapomorphies)

used to diagnose each of the subspecies, the CMA pres-

ents them in a phylogenetic and temporal framework.

Our results show trends in scutellation (e.g., presence-

absence, relative positions), relative tail length, and body

color pattern, including ontogenetic melanism. Are the

characters we used in the CMA stable in the subspecies?

That question remains for future investigation; however,

we have no evidence to the contrary. Indeed, we antici-

pate that these characters, and others likely to be revealed

through detailed studies, will exhibit stability.

Importantly, each of these traits is amenable to further

investigation and formal tests. For examples, what is

the evolutionary and ecological significance of tongue

color differences in beaded lizards (always pink) and

Gila monsters (always black), the extreme differences in

adult dorsal color pattern in H. h. exasperatum (yellow

is predominant) vs. H. h. alvarezi (dark brown and pat-

ternless predominate), and ontogenetic melanism in H. h.

alvarezi ? As we discussed, beaded lizards occupy similar

seasonally dry tropical forests, yet each of the subspe-

cies exhibits pronounced molecular and morphological

differentiation.

Similar types of questions concerning adaptation have

used a CMA to explore social systems and sexual dimor-

phisms in lizards (Carothers 1984), male fighting and

prey subjugation in snakes (Schuett et al. 2001), types

of bipedalism in varanoids (Schuett et al. 2009), and di-

rection of mode of parity (oviparous vs. viviparous) in

viperids (Fenwick et al. 2011).

Subspecies and the Taxonomy of Beaded

Lizards

Introduced in the late 19 th century by ornithologists to de-

scribe geographic variation in avian species, the concept

of subspecies and trinomial taxonomy exploded onto the

scene in the early 20 th century (Bogert et al. 1943), but

not without controversy. The use of subspecies has been

both exalted and condemned by biologists (see perspec-

tives by Mallet 1995; Douglas et al. 2002; Zink 2004;

Fitzpatrick 2010). Thousands of papers have been pub-

lished in an attempt to either bolster the utility and prom-

ulgation of subspecies, or to denounce the concept as

meaningless and misleading in evolutionary theory (Wil-

son and Brown 1953; Zink 2004). What is the problem?

One common critical response is that the subspecies con-

cept lacks coherence in meaning, and hence is difficult

to comprehend (Futuyma 1998; Zink 2004). Moreover,

the use of subspecies often masks real diversity (cryptic

species, convergence) or depicts diversity that is non-ex-

istent or only trivial (e.g., lack of support in DNA-based

analyses; Zink 2004). Indeed, as John Fitzpatrick attests

(2010, p. 54), “The trinomial system cannot accurately

represent the kind of information now available about ge-

netic and character variation across space. Instead, even

more accurate tools are being perfected for quantitative,

standardized descriptions of variation. These analyses —

not subspecies classifications — will keep providing new

scientific insights into geographic variation.”

Even with the identification of a variety of problems,

many authors recommend that complete abandonment

of the trinomial category in taxonomy is not necessary

nor advised (e.g., Mallett 1995, Hawlitschek et al. 2012).

Unfortunately, a consensus among biologists concerning

the use of subspecies is not likely to emerge (Fitzpatrick

2010). In step with Fitzpatrick’s (2010) comments, we

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Taxonomy and conservation of beaded lizards

contend that the plethora of variation detected in organ-

isms must be approached in a modern sense that does

not rely upon a cumbersome and outdated taxonomic

system. Indeed, we anticipate that the description of

geographic variation in organisms, once emancipated

from infraspecific taxonomy, will actually accelerate our

understanding of variation and its complexities. In our

view, the confusion in recognizing subspecies can also

mislead conservation planning, and it has on more than

one occasion (e.g., the dusky seaside sparrow, see Avise

and Nelson 1989). We thus agree with Wilson and Brown

(1953), Douglas et al. (2002), Zink (2004), Fitzpatrick

(2010) and others in their insightful criticisms leveled at

the subspecies concept and the use of trinomials in taxon-

omy. Other authors have echoed similar views (Burbrink

et al., 2000; Burbrink 2001; Douglas et al. 2007; Tobias

et al. 2010; Braby et al. 2011; Hoisington-Lopez 2012;

Porras et al. 2013).

Given our reassessment of molecular (mt- and

nDNAs), phylogeographic, morphological, and biogeo-

graphic evidence, we elevate the subspecies of Heloder-

ma horridum to the rank of full species (Wiley, 1978;

Zink 2004; Tobias et al. 2010; Braby et al. 2011; Porras

et al. 2013). Indeed, Douglas et al. (2010, p. 164) stated

that, “... unlike H. suspectum, our analyses support the

subspecific designations within H. horridum. However,

these particular lineages almost certainly circumscribe

more than a single species . . . Thus, one benefit of a con-

servation phylogenetic perspective is that it can properly

identify biodiversity to its correct (and thus manageable)

taxonomic level.” Accordingly, based on multiples lines

of concordant evidence, we recognize four species of

beaded lizards. They are:

Mexican beaded lizard: Heloderma horridum (Wieg-

mann 1829)

Rio Fuerte beaded lizard: Heloderma exasperatum

(Bogert and Martin del Campo 1956)

Chiapan beaded lizard: Heloderma alvarezi (Bogert

and Martin del Campo 1956)

Guatemalan beaded lizard: Heloderma charlesbogerti

(Campbell and Vannini, 1988)

In the above arrangement, we do not recognize subspe-

cies and vernacular names remain unchanged. The geo-

graphic distribution of the four species of beaded lizards

is presented in Fig. 7. Locality data for the map were

derived from Bogert and Martin del Campo (1956),

Campbell and Vannini (1988), Schwalbe and Lowe

(2000), Lemos-Espinal et al. (2003), Campbell and La-

mar (2004), Beck (2005), Monroy-Vilchis et al. (2005),

Ariano-Sanchez and Salazar (2007), Anzueto and Camp-

bell (2010), Domiguez-Vega et al. (2012), and Sanchez-

De La Vega et al. (2012). The “?” on the map (coastal

Oaxaca, municipality: San Pedro Tututepec) denotes a

jet-black adult specimen photographed by Vicente Mata-

Silva (pers. comm.) in December 2010. The validity of

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this record is questionable owing to its striking coloration

resemblance to H. alvarezi from the Central Depression

(Rio Grijalva Depression) of Chiapas and extreme west-

ern Guatemala, rather than to H. horridum. Although the

individual might represent an isolated population of H.

alvarezi , further study in this area of Oaxaca is required

to rule out human activity as an agent (e.g., displace-

ment).

Beaded Lizards and Seasonally Dry

Tropical Forests

The key to understanding the evolution and biogeogra-

phy of beaded lizards and the prospects for implementing

meaningful conservation measures is through a recogni-

tion of the biomes they occupy, which we emphasize are

the widely but patchily distributed low elevation season-

ally dry tropical forests (SDTFs; see Trejo and Dirzo

2000; Campbell and Lamar 2004; Beck 2005; Ariano-

Sanchez 2006; Miles et al. 2006; Pennington et al. 2006;

Dirzo et al. 2011; Domiguez-Vega et al. 2012).

The evolution of SDTFs in Mesoamerica is a complex

evolutionary scenario (Stuart 1954, 1966), and our un-

derstanding of their origin and temporal diversification

is in its infancy (Janzen, 1988; Becerra 2005; Pennington

et al. 2006; Dirzo et al. 2011; De-Nova et al. 2012). One

approach to grapple with complex issues such as the ori-

gin and historical construction of SDTFs in Mesoamerica

has been to examine a single but highly diverse plant tax-

on within a phylogenetic (phylogenomic) backdrop. This

approach, accomplished by Becerra (2005) and more re-

cently by De-Nova et al. (2012), uses the woody plant

(tree) Bursera (Burseracae, Sapindales), a highly diverse

genus (> 100 species) with a distribution in the New

World and emblematic of most dry forest landscapes

(De-Nova et al. 2012). Owing to this diversity, coupled

with extensive endemism, this taxon has yielded valuable

information that serves as a reasonable proxy for diver-

sification and expansion of the SDTF biomes (Dick and

Pennington 2012). Hence, plant (angio sperm) species

richness and expansion of SDTF biomes in Mesoamerica

is hypothesized to parallel the diversification of Bursera

(Dick and Wright 2005).

Based on both plastid and nuclear genomic markers

that were analyzed using fossil-calibrated techniques and

ancestral habitat reconstruction, the origin of Bursera in

Mesoamerica is hypothesized to be in northwestern Mex-

ico in the earliest Eocene (-50 mya), with subsequent ex-

tensive diversification and southern expansion along the

Mexican Transvolcanic Belt in the Miocene, especially

-7-10 mya (De-Nova et al. 2012). Accelerated clade di-

versification of Bursera and its sister genus Commiphora

occurred during the Miocene, a period of increased arid-

ity likely derived from seasonal cooling and rain shadow

effects (Dick and Wright 2005). Although causal con-

nections are complex, they include global tectonic pro-

July 2013 | Volume 7 | Number 1 | e67

Reiserer et al.

Fig. 7. The distribution of beaded lizards in Mexico and Guatemala. Colored dots represent verified sightings (populations) and

museum records. Note the fragmented populations of all four species, which closely approximates the patchy distribution of sea-

sonal dry tropical forests (see map in Brown and Lowe [1980]). See text for explanation of question marks (“?”) and other details.

cesses, orogenic activities (uplifting of the Sierra Madre

Occidental and Sierra Made Oriental) and local volca-

nism (Dick and Wright 2005; De-Nova et al. 2012). De-

Nova et al. (2012) concluded by emphasizing that their

phylogenomic analysis of Bursera points to high species

diversity of SDTFs in Mesoamerica that derives from

within-habitat speciation rates that occurred in the enve-

lope of increasing aridity from the early Miocene to the

present. Furthermore, they stated (p. 285), “This scenario

agrees with previous suggestions that [angiosperm] lin-

eages mostly restricted to dry environments in Mexico

resulted from long periods of isolated evolution rather

than rapid species generation....”

Beaded Lizard Evolution and Diversification

The phylogenetic analyses of Heloderma horridum

(sensu lato) by Douglas et al (2010) provided fossil-

calibrated estimates of divergence times, which allow us

to draw connections to the origin and diversification of

SDTFs in Mesoamerica (Table 1, Fig. 6). Based on those

analyses, H. horridum (sensu lato) and H. suspectum are

hypothesized to have diverged from a most-recent com-

mon ancestor in the late Eocene (~35 mya), which cor-

responds to the establishment of Bursera in northwestern

Mexico. Subsequent diversification (cladogenesis) of the

beaded lizards occurred during the late Miocene (9.71

mya), followed by a lengthy period of stasis of up to 5

my, with subsequent cladogenesis extending into the

Pliocene and Pleistocene. Of particular interest is that

this scenario approximately parallels the diversification

and southern expansion of SDTFs (Dick and Wright

2005; De-Nova et al. 2012). Accordingly, based on the

above discussion of SDTFs and phylogenetic analyses,

we suggest that beaded lizard lineage diversification

resulted from long periods of isolated (allopatric) evo-

lution in SDTFs. Douglas et al. (2010) referred to the

fragmented tropical dry forests of western Mexico as

“engines” for diversification. The extralimital distribu-

tion of H. exasperatum and H. horridum into adjacent

pine-oak woodland and thorn scrub biomes appears to be

relatively uncommon (Schwalbe and Lowe 2000; Beck

2005; Monroy-Vilchis et al. 2005).

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086

Taxonomy and conservation of beaded lizards

Conservation of Beaded Lizards

A primary aim of this paper is to provide a useful and

accurate synthesis of information on the taxonomy of

beaded lizards that will lead to informed decisions re-

garding their conservation (see Douglas et al., 2010).

Until recently, H. horridum (sensu lato) was designated

as Vulnerable on the World Conservation Union (IUCN)

Red List. In 2007, that designation was changed to Least

Concern based on more stringent criteria (Canseco-

Marquez and Munoz 2007; categories and criteria ver-

sion 3.1). The 2007 IUCN Red List also determined that,

“Additional research is needed into the taxonomic status,

distribution and threats to this species” (Canseco-Mar-

quez and Munoz 2007). The critically endangered status

of H. h. charlesbogerti (sensu lato) in Guatemala (Ari-

ano-Sanchez 2006; Ariano-Sanchez and Salazar 2007)

has not altered the current IUCN Red List designation

of this taxon, because population trends of other beaded

lizards in Mexico remain “unknown” (www.iucnredlist.

org/search; see International Reptile Conservation Foun-

dation, IRCF; www.ircf.org). As more information on the

population status of the newly elevated beaded lizards

becomes available, in view of their fragmented distribu-

tions and threats to their habitats, the IUCN likely will

designate these taxa as Vulnerable or a higher threat cat-

egory (see our EVS analysis below). For example, H. ex-

asperatum, H. alvarezi, and H. charlesbogerti all occupy

limited areas of SDTF (Beck 2005).

In Mexico, helodermatid lizards are listed as “threat-

ened” (amenazadas) under the Mexican law (NOM-

059-SEMARNAT-2010), legislation comparable to that

in the United States Endangered Species Act. The threat-

ened category from Mexican law coincides, in part, with

the “Vulnerable” category of the IUCN Red List. This

document defines “threatened” as species or populations

that could become at risk of extinction in a short to me-

dium period if negative factors continue to operate that

reduce population sizes or alter habitats. Heloderma h.

charlesbogerti (sensu lato) is listed on the Guatemalan

Lista Roja (Red List) as “endangered,” with approxi-

mately 200-250 adult individuals remaining in under

26,000 ha of its natural habitat of SDTF and thorn scrub,

(Ariano-Sanchez 2006).

Furthermore, H. h. charlesbogerti (sensu lato) is listed

on CITES Appendix I, a designation that includes spe-

cies threatened with extinction (see CITES document

appended to Ariano-Sanchez and Salazar 2007). Trade

in CITES Appendix I species is prohibited except under

exceptional circumstances, such as for scientific research

(CITES 2007). The remaining taxa of Heloderma hor-

ridum (sensu lato) ( H . h. alvarezi, H. h. exasperatum,

and H. h. horridum) are listed on Appendix II of CITES

(CITES 2007). International trade in Appendix II species

might be authorized under an export permit, issued by

the originating country only if conditions are met that

show trade will not be detrimental to the survival of the

Amphib. Reptile Conserv. | http://amphibian-reptile-conservation.org 087

species in the wild. The United States Fish & Wildlife

Service issues permits only if documentation is provided

proving legal origin, including a complete paper trail

back to legal founder animals. This procedure allows the

importation of beaded lizards into the United States to

be tightly regulated (in theory), and also subjects such

imports to provisions of the Lacey Act that control com-

merce in illegally obtained fish and wildlife (Beck 2005).

Beaded Lizards: Denizens of Endangered

SDTFs

Although occasional sightings of beaded lizards have

been reported from mid elevation pine-oak woodlands, all

four species primarily inhabit lowland SDTFs and rarely

in associated thorn scrub, in both Mexico and Guatemala

(Schwalbe and Lowe 2000; Lemos-Espinal et al. 2003;

Campbell and Lamar 2004; Beck 2005; Monroy-Vilchis

et al. 2005; Ariano and Salazar 2007; Domiguez-Vega et

al. 2012). Thus, the optimal measure to reduce threats to

beaded lizards is to maintain the integrity of their tropi-

cal dry forest habitats. Current threats to beaded lizards

throughout their range include habitat loss, road mor-

tality, poaching, and illegal trade (Beck 2005; Miles et

al. 2006; Golicher et al. 2012). Habitat loss takes many

forms, from the conversion of SDTFs to areas of agricul-

ture and cattle ranching, to forest fragmentation owing

to roads and other forms of development (Pennington et

al. 2006). Degradation from human-introduced invasive

(exotic) organisms and fire also are contributing factors

(Beck 2005).

When the Spaniards arrived in the Western Hemi-

sphere, Mesoamerican SDTFs covered a region stretch-

ing from Sonora (Mexico) to Panama, an area roughly the

size of France (-550,000 km 2 ). Today, only 0.1% of that

region (under 500 km 2 ) has official conservation status,

and less than 2% remains sufficiently intact to attract the

attention of conservationists (Janzen 1988; Hoekstra et

al. 2005). Of all 13 terrestrial biomes analyzed by Hoek-

stra et al. (2005), the SDTF biome has the third highest

conservation risk index (ratio of % land area converted

per % land area protected), far above tropical wet forest

and temperate forest biomes (Miles et al. 2006).

Mexico ranks among the most species rich countries

in the world (Garcia 2006; Urbina-Cardona and Flores-

Villela 2010; Wilson and Johnson 2010; Wilson et al.

2010, 2013). Nearly one-third of all the Mexican herpe-

tofaunal species are found in SDTFs (Garcia 2006; De-

Nova et al. 2012). Neotropical dry forests span over 16

degrees of latitude in Mexico, giving way to variation

in climatic and topography that results in a diversity of

tropical dry forest types, and a concurrent high propor-

tion of endemism of flora and fauna (Garcia 2006; De-

Nova et al. 2012; Wilson et al. 2010; 2013). Mexican

seasonally tropical dry forest, classified into seven ecore-

gions that encompass about 250,000 km 2 , has enormous

conservation value and has been identified as a hotspot

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Reiserer et al.

for conservation priorities (Myers et al. 2000; Sanchez-

Azofeifa et al. 2005; Garcia 2006; Urbina-Cardona and

Flores-Villela, 2010; Wilson et al. 2010, Mittermeier et

al. 2011). The vast majority (98%) of this region, how-

ever, lies outside of federally protected areas (De-Nova

et al. 2012). With few exceptions, most of the protected

areas in Mexico occur in the states of Chiapas and Jalis-

co, leaving much of the region (e.g., Nayarit and Sinaloa)

without government (federal) protection (Garcia 2006).

In Guatemala, less than 10% of an estimated 200,000

ha of original suitable habitat have been established as

protected critical habitat in the Motagua Valley for the

endangered H. charlesbogerti (Najera Acevedo 2006). A

strong effort led by local citizens, conservation workers,

biologists, government officials, NGOs, and conserva-

tion organizations (e.g., The Nature Conservancy, Inter-

national Reptile Conservation Association, Zoo Atlanta,

and Zootropic) negotiated to have H. h. charlesbogerti

(sensu lato) placed on CITES Appendix I, to purchase

habitat, conduct research, employ local villagers in mon-

itoring the lizards, and promote environmental education

(Lock 2009). Similar efforts for beaded lizards have been

underway for many years in Chiapas (Mexico), spear-

headed at ZooMAT (Ramirez-Velazquez 2009), and in

Chamela, Jalisco (www.ibiologia.unam.mx/ebchamela/

www/reserva.html). Such efforts will need to expand in

the years ahead and will doubtless play a crucial role if

we hope to retain the integrity of existing SDTFs inhab-

ited by beaded lizards throughout their range.

Discussion

In this paper, we reassessed the taxonomy of Heloderma

horridum (sensu lato) using both published information

and new analyses (e.g., CMA). We concluded that diver-

sity in beaded lizards is greater than explained by infra-

specific differences and that the recognition of subspecies

is not warranted, as it obscures diversity. Our decision to

elevate the four subspecies of H. horridum to full species

status is not entirely novel (Beck 2005; Douglas et al.

2010). Furthermore, our taxonomic changes are based on

integrative information (i.e., morphology, mt- and nDNA

sequence information, biogeography) and changing per-

spectives on the utility of formally recognizing infraspe-

cific diversity using a trinomial taxonomy (Wilson and

Brown 1953; Douglas et al. 2002; Zink 2004; Porras et

al. 2013). This decision not only adds to a better under-

standing of the evolution of helodermatids, but also pro-

vides an important evolutionary framework from which

to judge conservation decisions with prudence (Douglas

et al. 2002).

Below, we delineate and discuss prospective research

and conservation recommendations for beaded lizards

based on our present review. Borrowing some of the

guidelines and recommendations for future research and

conservation for cantils, also inhabitants of SDTFs, by

Porras et al. (2013), we outline similar ones for the four

Amphib. Reptile Conserv. | http://amphibian-reptile-conservation.org 088

species of beaded lizards ( H . alvarezi, H. charlesbogerti ,

H. exasperatum, and H. horridum ).

Future Research and Conservation

Recommendations

I . Throughout this paper we emphasized the importance

of SDTFs in the distribution of beaded lizards, yet most

SDTFs within their distribution are not Protected Natural

Areas (PNAs; Beck 2005; Urbina-Cardona and Flores-

Villela 2009; Domiguez-Vega et al. 2012). Accordingly,

emphasis should be placed on those areas of SDTFs for

prospective research, new conservation projects, and for

establishing new PNAs. The protection of beaded liz-

ards must be placed into a larger context of conservation

planning. Proper stewardship of SDTFs and other biomes

must include meaningful (scientific) protective measures

for all of the flora and fauna, rather than piecemeal (e.g.,

taxon-by-taxon) approaches that lack a cohesive conser-

vation plan (Douglas et al. 2010).

We applaud the efforts of Domiguez-Vega et al.

(2012) in identifying conservation areas for beaded liz-

ards; however, we do not agree with all of their conclu-

sions. In particular, based on field experiences by one

of us (DDB), we contend that the potential (predicted)

range of H. exasperatum in Sonora (Mexico) based on

the results of their habitat suitability modeling, appears

exaggerated and thus may be misleading. In our opin-

ion, their distribution maps (figs. 2 and 3) overestimate

the extent of true SDTFs in Sonora, showing their occur-

rence in a type of biome that is more accurately classi-

fied as Sinaloan Thorn Scrub (see the excellent maps in

Brown and Lowe 1980; Robichaux and Yetman 2000).

In Sonora, beaded lizards ( H . exasperatum) are rarely

found in association with pure thorn scrub, while Gila

monsters, in contrast, are frequently encountered in that

type of habitat (Schwalbe and Lowe 2000; Beck 2005).

2. With few exceptions, the population viability of beaded

lizards is largely unknown (Beck 2005; Ariano- Sanchez

2006; Ariano- Sanchez et al. 2007; Domiguez-Vega et al.

2012). We highly recommend that modem assessments

of the four species occur at or near localities where they

have been recorded (e.g., Jimenez- Valverde and Lobo

2007). Whereas H. charlesbogerti , and to a lesser degree

H. alvarezi (Ramirez-Velazquez 2009), are receiving in-

ternational conservation attention, we feel that similar

consideration is necessary for H. exasperatum owing

to its relatively limited geographic range (Sonora, Chi-

huahua, Sinaloa), the large extent of habitat destruction

and fragmentation (Fig. 8), and limited areas receiving

protection (Trejo and Dirzo 2000; Domiguez-Vega et

al. 2012; see http://www.conanp.gob.mx/regionales/). In

1996, about 92, 000 hectares in the Sierra de Alamos and

the upper drainage of the Rio Cuchujaqui were declared

a biosphere reserve by the Secretary of the Environment

and Natural Resources (SEMARNAT 2010), called the

July 2013 | Volume 7 | Number 1 | e67

Taxonomy and conservation of beaded lizards

/ ✓

Area de Protection de Fauna y Flora Sierra de Alamos

y Rio Cuchujaqui (Martin and Yetman 2000; S. Meyer,

pers. comm.). Efforts continue in Sonora to set aside ad-

ditional habitat for conservation, but, other than Alamos,

no other areas with true SDTFs presently exist (Robich-

aux and Yetman 2000; S. Meyer, pers. comm.).

3. Conservation management plans for each of the spe-

cies of beaded lizards should be developed from an

integrative perspective based on modern population

assessments, genetic information, and ecological (e.g.,

soil, precipitation, temperature) and behavioral data

(e.g., social structure, mating systems, home range size).

Such a conservation plan is in place for the Guatemalan

beaded lizard ( H . charlesbogerti ) by CONAP-Zootropic

(www.ircf.org/downloads/PCHELODERMA-2Web.

pdf). Also, aspects of burgeoning human population

growth must be considered, since outside of PNAs these

large slow -moving lizards generally are slaughtered on

sight, killed on roads by vehicles (Fig. 9), and threatened

by persistent habitat destruction primarily for agriculture

and cattle ranching (Fig. 10). For discussions on conser-

vation measures in helodermatid lizards, see Sullivan et

al. (2004), Beck (2005), Kwiatkowski et al. (2008), Doug-

las et al. (2010), Domfguez-Vega et al. (2012), and Ariano-

Sanchez and Salazar (2013).

In Mexico, the IUCN lists

Heloderma horridum (sensu

lato) under the category of Least

Concern. Recently, Wilson et al.

(2013) reported the Environmen-

tal Vulnerability Score (EVS)

for H. horridum (sensu lato) as

11. Briefly, an EVS analysis as-

sesses the potential threat sta-

tus of a given species based on

multiple criteria and provides a

single score or index value (Wil-

son and McCranie 2004; Porras

et al. 2013; Wilson et al. 2013).

High EVS scores (e.g., 17), for

example, signify vulnerability.

With the taxonomic changes we

proposed for beaded lizards, an

EVS assessment is thus required

for each species. Using the new

criteria developed by Wilson et

al. (2013; see Porras et al. 2013),

we recalculated the EVS for the

species of beaded lizards, which

are presented below:

Fig. 8. Destruction of seasonally dry tropical forest near Alamos, Sonora, Mexico.

Photo by Daniel D. Beck.

H. horridum'. 5 + 4 + 5 = 14

H. exasperatum : 5 + 7 + 5 = 17

H. alvarezi'. 4 + 6 + 5 = 15

H. charlesbogerti'. 4 + 8 + 5 = 17

Fig. 9. A dead-on-the-road (DOR) H. exasperatum (sensu stricto) near Alamos, Sonora,

Mexico. Vehicles on paved roads are an increasing threat to beaded lizards, Gila monsters,

and other wildlife. Photo by Thomas Wiewandt.

These recalculated values fall into

the high vulnerability category

(Wilson et al. 2013; Porras et al.

2013), underscoring the urgency

for the development of conserva-

tion management plans and long-

term population monitoring of all

species of beaded lizards. These

values thus need to be reported

to the appropriate IUCN commit-

tees, so immediate changes in sta-

tus can be made and conservation

actions implemented.

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090

Reiserer et al.

Fig. 10. Agave cultivation in Mexico results in the destruction of seasonally dry tropical

forests. Photo by Thomas Wiewandt.

natural habitat, small population

size (200-250 adults) and endan-

gered status, H. charlesbogerti is

currently listed as CITES Appen-

dix I (Ariano- Sanchez and Sala-

zar 2007). Given the taxonomic

elevation of these taxa, conserva-

tion agencies can use these char-

ismatic lizards as flagship species

in efforts to publicize conserva-

tion efforts in their respective

countries at all levels of interest

and concern, including educa-

tion and ecotourism (Beck 2005).

Eli Lilly Co., Disney Worldwide

Conservation Fund and The Na-

ture Conservancy support the

conservation of H. charlesboger-

ti (Ariano-Sanchez and Salazar

2012). Such corporate involve-

ment provides funds and positive

public exposure (e.g., social net-

work advertising) that otherwise

would not be possible.

Fig. 11. Antonio Ramirez Ramirez- Velazquez, a herpetologist, discusses the beauty and

importance of beaded lizards ( H . alvarezi, sensu stricto) to a group of enthusiastic children

and their teacher at Zoo Miguel Alvarez del Toro (ZooMAT) in Tuxtla Gutierrez, Chiapas,

Mexico. The zoo was named in honor of its founding director, Senor Miguel Alvarez del

Toro, who had a keen academic and conservation interest in beaded lizards. He collected

the type specimen of H. alvarezi (described in Bogert and Martin del Campo, 1956), which

was named in his honor. ZooMAT offers hands-on environmental education programs to

schoolchildren and other citizens of southern Mexico. Photo by Thomas Wiewandt.

4. We recommend the establishment of zoo conservation

(AZA) educational outreach programs, both ex situ and

in situ, such as those currently in progress for H. charles-

bogerti (www.IRCF.org;www.zooatlanta.org) and for

H. alvarezi in Chiapas (Ramirez-Velazquez, 2009, see

Fig. 11). Because of its limited range, destruction of its

5. One of the major conclusions

of this paper is that our knowl-

edge of the taxonomy and phy-

logeography of beaded lizards

remains at an elementary level.

As discussed, a robust phylogeo-

graphic analysis using morpho-

logical characters is not avail-

able. Our character mapping

exercise, for various reasons, is

not a substitute procedure for

detailed phylogenetic analyses

using morphology (Assis 2009;

Assis and Rieppel 2011). Other

authors have made similar pleas

concerning the importance of

morphology, including fossils, in

phylogenetic reconstruction (Poe

and Wiens 2000; Wiens 2004,

2008; Gauthier et al. 2012).

Moreover, further studies on the

historical biogeography of he-

lodermatids (e.g., ancestral area

reconstruction) are needed (e.g.,

Ronquist 1997, 2001; Ree and

Smith 2008). Detailed morpho-

logical analyses can be conducted with new tools such as

computed tomography (CT) scans of osteological char-

acters of both extant and fossil specimens (Gauthier et al.

2012), and geometric morphometric approaches to exter-

nal characters (Davis 2012). Furthermore, in the expand-

ing field of “venomics” new venom characters in beaded

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Taxonomy and conservation of beaded lizards

lizards will likely be discovered, which might prove use-

ful in phylogenetic analyses (Fry et al. 2009, 2010).

As we progress into the “Age of Genomics” with

ever-growing computational advancements (e.g., bio-

informatics; Homer et al. 2009), new and exciting meth-

ods to explore organismal diversity are opening, includ-

ing such next-generation approaches as pyrosequencing

(microsatellite isolation), establishing transcriptome

databases, and whole-genome sequencing (Wiens 2008;

Castoe et al. 2011; Culver et al. 2011). Currently, plans

are underway to apply pyrosequencing methods to helo-

dermatids to generate a nearly inexhaustible supply of

microsatellite markers for a variety of proposed analy-

ses (W. Booth and T. Castoe, pers. comm.). Standing on

the shoulders of The Human Genome Project (Culver et

al. 2011), and reaping the success of genome projects in

other reptilian taxa (Castoe et al. 2011), it is now possible

to establish a “Helodermatid Genome Project.” Beaded

lizards and the Gila monster are especially good candi-

dates for such an investment, especially given the impor-

tance of their venom components in medical research and

recent pharmaceutical applications (Beck 2005; Douglas

et al. 2010; Fry et al. 2009, 2010).

6. An important take-home message from Douglas et al.

(2010) is that future conservation efforts will require a

robust understanding of phylogenetic diversity (e.g.,

conservation phylogenetics) to make sensible (logical)

and comprehensive conservation plans. For example, the

range of H. horridum (sensu stricto) is the most expansive

of the species of beaded lizards and has not been fully

explored with respect to genetic diversity. Accordingly,

sampling throughout its range may yield cryptic genetic

diversity, perhaps even new species. We emphasize that

viable conservation planning must incorporate all intel-

lectual tools available, including those that incorporate

old methods (e.g., paleoecological data) but viewed

through a new lens (Douglas et al. 2007, 2009; Willis

et al. 2010). Wisely, Greene (2005) reminds us that we

are still grappling with understanding basic and essential

issues concerning the natural history of most organisms.

To that end, we must continue in our efforts to educate

students and the public of the need for and importance of

this branch of science.

7. The new taxonomic arrangement of beaded lizards

we proposed will affect other fields of science, such as

conservation biology and human medicine (Beck, 2005;

Douglas et al., 2010). In Fry et al. (2010, p. 396, table 1),

toxins are matched to the subspecies of beaded lizards

and Gila monsters. Yet as noted by Beck (2005) and

Douglas et al. (2010), the banded Gila monster (H. s.

cinctum) is not a valid subspecies, which is based on

several levels of analysis (i.e., morphology, geographic

distribution, and haplotype data). Individuals assigned to

H. s. cinctum based on color and pattern, for example,

have been found in southwestern Arizona near the Mexi-

can border and in west-central New Mexico (Beck 2005).

Furthermore, most venom researchers, including those

who study helodermatids, often obtain samples from cap-

tive subjects in private collections and zoological institu-

tions. Many of these animals have been bred in captivity

and result from crossing individuals of unknown origin

or from different populations (D. Boyer, pers. comm).

Among other negative outcomes, such “mutts” will con-

found results of the true variation of venoms. Geographic

and ontogenetic variation in venom constituents is well

established in other squamates (Minton and Weinstein

1986; Alape-Giron et al. 2008; Gibbs et al. 2009), which

is apparently the case in helodermatids (Fry et al. 2010).

Thus, we strongly encourage researchers investigating

helodermatid venoms for molecular analysis and phar-

maceutical development to use subjects with detailed lo-

cality information, as well as age, gender, and size, and

to provide those data in their publications.

8. Owing to problems that many scientists, their stu-

dents, and other interested parties from Mesoamerica

have in gaining access to primary scientific literature,

we highly recommend that authors seek Open Access

peer-reviewed journals as venues for their publications

on beaded lizards, an important factor in our choice for

selecting the present journal (www.redlist-ARC.org) as a

venue for our data and conservation message.

Acknowledgments. — We thank Larry David Wilson

for inviting us to participate in the Special Mexico Is-

sue. A Heritage Grant from the Arizona Game and Fish

Department and a Research Incentive Award/Scholarly

Research and Creative Activities Award (Arizona State

University) awarded to GWS funded parts of this re-

search. Zoo Atlanta (Dwight Lawson, Joe Mendelson III)

and Georgia State University (Department of Biology)

provided various levels of support. Warren Booth, Donal

Boyer, Dale DeNardo, Andres Garcia, Stephanie Mey-

er, and Tom Wiewandt were always willing to discuss

beaded lizard and tropical dry forest biology with us. We

thank Brad Lock, Louis Porras, and Larry David Wilson

for their suggestions and valuable insights in improving

an earlier version of this manuscript. Also, three review-

ers, including Daniel Ariano-Sanchez, provided key

information and sharpened our focus, though we bear

the burden of any blunders. We thank Javier Alvarado,

Daniel Ariano-Sanchez, David Brothers, Quetzal Dwyer,

Kerry Holcomb, Vicente Mata-Silva, Stephanie Meyer,

Adam Thompson, and Tom Wiewandt for graciously

supplying us with images. Vicente Mata-Silva kindly as-

sisted us in preparing the resumen and locating literature

on Heloderma.

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Literature Cited

Alape-Giron A, Sanz L, Escolano J, Flores-Dfaz M,

Madrigal M, Sasa M, et al. 2008. Snake venomics of

the lancehead pitviper Bothrops asper : geographic,

individual, and ontogenetic variations. Journal of

Proteome Research 7: 3556-3571.

Alvarez del Toro M. 1983 (1982). Los Reptiles de Chi-

apas (3 rd edition). Publicacion del Instituto de Historia

Natural, Tuxtla Gutierrez, Chiapas, Mexico.

Anzueto VR, Campbell JA. 2010. Guatemalan beaded

lizard ( Heloderma horridum charlesbogerti ) on the

Pacific versant of Guatemala. The Southwestern Natu-

ralist 55: 453-454.

Ariano-Sanchez D. 2006. The Guatemalan beaded lizard:

endangered inhabitant of a unique ecosystem. Iguana

13: 179-183.

Ariano-Sanchez D, Salazar G. 2007. Notes on the distri-

bution of the endangered lizard, Heloderma horridum

charlesbogerti, in the dry forests of eastern Guatema-

la: an application of multi-criteria evaluation to con-

servation. Iguana 14: 152-158.

Ariano-Sanchez D, Salazar G. 2012. Natural History

Notes. Heloderma horridum charlesbogerti (Guate-

malan beaded lizard). Shelter use. Herpetological Re-

view 43: 645-646.

Ariano-Sanchez D, Salazar G. 2013. Natural History

Notes. Heloderma horridum charlesbogerti (Guate-

malan Beaded Lizard). Wild reproductive ecology.

Herpetological Review 44: 324.

Assis LCC. 2009. Coherence, correspondence, and the

renaissance of morphology in phylogenetic systemat-

ics. Cladistics 25: 528-544.

Assis LCC, Rieppel O. 201 1 . Are monophyly and synapo-

morphy the same or different? Revisiting the role of

morphology in phylogenetics. Cladistics 27: 94-102.

Avise JC. 2005. Phylogenetic units and currencies above

and below the species level. Pp. 76-119 In: Phyloge-

ny and Conservation. Editors, Purvis A, Gittleman JL,

Brooks T. Cambridge University Press, Cambridge,

United Kingdom.

Avise JC. 2008. Three ambitious (and rather unorthodox)

assignments for the field of biodiversity genetics. Pro-

ceedings of the National Academy of Sciences USA

105: 11564-11570.

Avise JC, Nelson WS. 1989. Molecular genetic relation-

ships of the extinct dusky seaside sparrow. Science

243 : 646-649.

Avise JC, Hubbell SP, Ayala FJ. 2008. In the light of evo-

lution II: biodiversity and extinction. Proceedings of

the National Academy of Sciences USA 105: 1 1453—

11457.

Beaman KR, Beck DD, McGurty BM. 2006. The beaded

lizard {Heloderma horridum) and Gila monster {Helo-

derma suspectum): a bibliography of the family Helo-

dermatidae. Smithsonian Herpetologica Information

Service 136: 1-66.

Amphib. Reptile Conserv. | http://amphibian-reptile-conservation.org 092

Becerra JX. 2005. Timing the origin and expansion of the

Mexican tropical dry forests. Proceedings of the Na-

tional Academy of Sciences USA 102: 10919-10923.

Beck DD. 2005. Biology of Gila Monsters and Beaded

Lizards. University of California Press, Berkeley,

California, USA.

Beck DD, Lowe CH. 1991. Ecology of the beaded liz-

ard, Heloderma horridum, in a tropical dry forest in

Jalisco, Mexico. Journal of Herpetology 25: 395-406.

Bergsten J. 2005. A review of long-branch attraction.

Cladistics 21: 163-193.

Bogert CM, Blair WF, Dunn ER, Hall ER, Hubbs CL,

Mayr E, Simpson GG. 1943. Criteria for vertebrate

subspecies, species and genera. Annals of the New

York Academy of Sciences 34: 105-188.

Bogert CM, Martin del Campo R. 1956. The Gila monster

and its allies: the relationships, habits, and behavior of

the lizards of the family Helodermatidae. Bulletin of

the America Museum of Natural History 109: 1-238.

Braby MF, Eastwood R, Murray N. 2012. The subspecies

concept in butterflies: Has its application in taxonomy

and conservation biology outlived its usefulness? Bio-

logical Journal of the Linnean Society 106: 699-716.

Brooks DR, McLennan DA. 1991. Phylogeny, Ecology,

and Behavior: A Research Program in Comparative

Biology. The University of Chicago Press, Chicago,

Illinois, USA.

Brown DK, Lowe CH. 1980. Biotic communities of the

Southwest. U.S. Forest Service General Technical Re-

port RM-78 (map).

Burbrink, FT. 2001. Systematics of the eastern ratsnake

complex {Elaphe obsoleta). Herpetological Mono-

graphs 15: 1-53.

Burbrink FT, Lawson R, Slowinski JB. 2000. Mitochon-

drial DNA phylogeography of the polytypic North

American rat snake (Elaphe obsoleta ): a critique of

the subspecies concept. Evolution 54: 2107-2118.

Campbell, JA, Lamar WW. 2004. The Venomous Reptiles

of the Western Hemisphere (2 volumes). Comstock

Publishing Associates, Cornell University Press, Itha-

ca, New York, USA.

Campbell JA, Vannini JP. 1988. A new subspecies of

beaded lizard, Heloderma horridum, from the Mo-

tagua Valley of Guatemala. Journal of Herpetology

22: 457-468.

Canseco Marquez, L, Munoz, A. 2007. Heloderma hor-

ridum. In IUCN 2012. IUCN Red List of Threatened

Species, version 2012.2.

Carothers JH. 1984. Sexual selection and sexual dimor-

phism in some herbivorous lizards. The American

Naturalist 109: 83-92.

Castoe TA, de Koning APJ, Kim, HM, Gu W, Noonan

BP, Naylor G, Jiang ZJ, Parkinson CL, Pollock DD.

2009. Evidence for an ancient adaptive episode of

convergent molecular evolution. Proceedings of the

National Academy of Sciences USA 106: 8986-8991.

July 2013 | Volume 7 | Number 1 | e67

Taxonomy and conservation of beaded lizards

Castoe TA, de Koning APJ, Hall KT, Yokoyama KD, Gu

WJ, Smith EN, Feschotte C, Uetz P, Ray DA, Dobry

J, Bogden R, Mackessy SP, Bronikowski AM, Warren

WC, Secor SM, Pollock DD. 2011. Sequencing the

genome of the Burmese python {Python molurus

bivittatus ) as a model for studying extreme adapta-

tions in snakes. Genome Biology 12: 406.

CONAP-Zootropic. Available: www.ircf.org/downloads/

PCHELODERMA-2Web.pdf [Accessed: 17 June

2013].

Conrad JL, Montanari S, Aast JC, Norell MA. 2010. A

combined evidence phylogenetic analysis of Angui-

morpha (Reptilia: Squamata). Cladistics 26: 1-48.

Convention on International Trade in Endangered Spe-

cies (CITES) of Wild Fauna and Flora. 2007. Resume

of the 14 th Convention of the Parts, The Hague, The

Netherlands.

Culver M, Fitak R, Herrmann H-W. 2011. Genetic meth-

ods for biodiversity assessment. Pp. 208-335 In: Bio-

logical Diversity: Frontiers in Measurement and As-

sessment. Editors, Magurran AE, McGill BJ. Oxford

University Press, New York, USA.

Davis MA. 2012. Morphometries, molecular ecology and

multivariate environmental niche modeling define the

evolutionary history of the western rattlesnake (Cota-

lus viridis) complex. Ph.D. Dissertation, University of

Illinois at Urbana-Champaign, Illinois, USA.

De-Nova JA, Medina R, Montero JC, Weeks A, Rosell

JA, Olson ME, Eguiarte LE, Magallo S. 2012. In-

sights into the historical construction of species-rich

Mesoamerican seasonally dry tropical forests: the

diversification of Bursera (Burseraceae, Sapindales).

New Phytologist 193: 276-287.

Dick CW, Wright J. 2005. Tropical mountain cradles

of dry forest diversity. Proceedings of the National

Academy of Sciences USA 102: 10757-10758.

Dick CH, Pennington RT. 2012. Molecular systematic

perspective on biome origins and dynamics. New Phy-

tologist 193: 9-11.

Dirzo R, Young HS, Mooney HA, Ceballos G. 2011. (Ed-

itors). Seasonally Dry Tropical Forests. Island Press,

Washington, DC, USA.

Domlguez-Vega H, Monroy-Vilchis O, Balderas- Valdiv-

ia, Gienger CM, and Ariano- Sanchez D. 2012. Pre-

dicting the potential distribution of the beaded lizard

and identification of priority areas for conservation.

Journal for Nature Conservation 20: 247-253.

Douglas ME, Douglas MR, Schuett GW, Porras LW, and

Holycross AT. 2002. Phylogeography of the western

rattlesnake ( Crotalus viridis ) complex, with empha-

sis on the Colorado Plateau. Pp. 1 1-50 In: Biology of

the Vipers. Editors, Schuett GW, Hoggren H, Doug-

las ME, and Greene HW. Eagle Mountain Publishing,

LC, Eagle Mountain, Utah, USA.

Douglas ME, Douglas MR, Schuett GW, Porras LW,

Thomason BL. 2007. Genealogical concordance

between mitochondrial and nuclear DNAs supports

Amphib. Reptile Conserv. | http://amphibian-reptile-conservation.org 093

species recognition of the Panamint rattlesnake ( Cro-

talus mitchellii stephensi). Copeia 2007: 920-932.

Douglas ME, Douglas MR, Schuett GW, Porras LW.

2009. Climate change and evolution of the New

World pitviper genus Agkistrodon (Viperidae). Jour-

nal of Bio geography 36: 1164-1180.

Douglas ME, Douglas MR, Schuett GW, Beck DD, Sul-

livan BK. 2010. Conservation phylogenetics of he-

lodermatid lizards using multiple molecular markers

and a supertree approach. Molecular Phylogenetics

and Evolution 55: 153-167.

Estes R, de Queiroz K, Gauthier JA. 1988. Phylogenetic

relationships within Squamata. Pp. 119-281 In: Phy-

logenetic Relationships of the Lizard Families. Edi-

tors, Estes R, Pregill GK. Stanford University Press,

Stanford, California, USA.

Fenwick AM, Greene HW, Parkinson CL. 2011. The ser-

pent and the egg: Unidirectional evolution of repro-

ductive mode in vipers? Journal Zoological Systemat-

ics and Evolutionary Research 50: 59-66.

Fitzpatrick JW. 2010. Subspecies are for convenience.

Ornithological Monographs 67: 54-61.

Freeman S, Herron JC. 2004. Evolutionary Analysis (3 rd

edition). Prentice Hall, Upper-Saddle River, New Jer-

sey, USA.

Fry BG et al. 2009. Novel venom proteins produced by

differential domain-expression strategies in beaded

lizards and Gila monsters (genus Heloderma). Mo-

lecular Biology and Evolution 27: 395-407.

Fry BG et al. 2010. Functional and structural diversifica-

tion of the Anguimorpha lizard venom system. Mo-

lecular and Cellular Proteomics 9: 2369-2390.

Futuyma DJ. 1998. Evolutionary Biology (3 rd edition).

Sinauer Associates, Sunderland, Massachusetts, USA.

Garcia A. 1995. Conserving neotropical biodiversity: the

role of dry forests in Western Mexico. Conservation

Biology 9: 1349-1353.

Garcia A. 2006. Using ecological niche modeling to

identify hotspots for the herpetofauna of the Pacific

lowlands and adjacent interior valleys of Mexico. Bio-

logical Conservation 130: 25-46.

Gauthier JA, Kearney M, Maisano JA, Rieppel O, Behl-

ke ADB. 2012. Assembling the squamate Tree of Life:

perspectives from the phenotype and the fossil record.

Bulletin of the Peabody Museum of Natural History

53: 3-308.

Gibbs HL, Sanz L, Calvete JJ. 2009. Snake population

venomics: proteomics-based analyses of individual

variation reveals significant gene regulation effects on

venom protein expression in Sistrurus rattlesnakes.

Journal of Molecular Evolution 68: 113-25.

Golicher DJ, Cayuela L, Newton, AC. 2012. Effects of

climate change on the potential species richness of

Mesoamerican forests. Biotropica 44: 284-293.

Greene HW. 2005. Organisms in nature as a central fo-

cus for biology. Trends In Ecology & Evolution 20:

23-27.

July 2013 | Volume 7 | Number 1 | e67

Reiserer et al.

Harvey PH, Pagel MD. 1991. The Comparative Method

in Evolutionary Biology. Oxford University Press,

Oxford, United Kingdom.

Hawlitschek, O, Nagy ZT, and Glaw F. 2012. Island evo-

lution and systematic revision of Comoran snakes:

why and when subspecies still make sense. PLoS

ONE 7: e42970.

Hoekstra JM, Boucher TM, Ricketts TH, Roberts C.

2005. Confronting a biome crisis: global disparities of

habitat loss and protection. Ecology Letters 8: 23-29.

Hoisington-Lopez JL, Waits LP, Sullivan J. 2012. Spe-

cies limits and integrated taxonomy of the Idaho

ground squirrel ( Urocitellus brunneus ): genetic and

ecological differentiation. Journal of Mammalogy 93:

589-604.

Homer DS, Pavesi G, Castrignano T, D’Onorio De Meo

P, Liuni S, Sammeth M, Picardi E, Pesole G. 2009.

Bioinformatics approaches for genomics and post ge-

nomics applications of next-generation sequencing.

Briefings in Bioinformatics 2: 181-197.

Huelsenbeck JP, Rohnquist F. 2001. MrBayes: Bayesian

inference of phylogeny. Bioinformatics 17: 754-755.

IUCN 2012. IUCN Red List of Threatened Species.

Version 2012.2. Available: www.iucnredlist.org [Ac-

cessed: 7 June 2013].

Janzen DH. 1988. Tropical dry forests: the most en-

dangered major tropical ecosystem. Pp. 130-137 In:

Biodiversity. Editor, Wilson EO. National Academy

Press, Washington, D.C., USA.

Jimenez-Valverde A, Lobo JM. 2007. Threshold crite-

ria for conversion of probability of species presence

to either-or presence-absence. Acta Oecologica 31:

361-369.

Johnson JD, Mata-Silva V, Rarmrez-Bautista A. 2010.

Geographic distribution and conservation of the

herpetofauna of southeastern Mexico. Pp. 323-369

In: Conservation of Mesoamerican Amphibians and

Reptiles. Editors, Wilson LD, Townsend JH, Johnson

JD. Eagle Mountain Publishing, LC, Eagle Mountain,

Utah, USA.

Kraus F. 1988. An empirical evaluation of the use of the

ontogeny polarization criterion in phylogenetic infer-

ence. Systematic Zoology 37: 106-141.

Kwiatkowski MA, Schuett GW, Repp RA, Nowak EN,

Sullivan BK. 2008. Does urbanization influence the

spatial ecology of Gila monsters in the Sonoran Des-

ert? Journal of Zoology 276: 350-357.

Lee MSY. 2009. Hidden support from unpromising data

sets strongly unite snakes with anguimorph “lizards.”

Journal of Evolutionary Biology 22: 1308-1316.

Lemos-Espinal JA, Chiszar D, Smith HM. 2003. Pres-

ence of the Rfo Fuerte beaded lizard ( Heloderma hor-

ridum exasperatum) in western Chihuahua. Bulletin of

the Maryland Herpetological Society 39: 47-51.

Lock B. 2009. Project Heloderma'. A Conservation Pro-

gram for the Guatemalan Beaded Lizard. CONNECT:

May 2009: 22-24. International Reptile Conservation

Foundation, San Jose, California, USA.

Losos JB, Hillis DM, Greene HW. 2012. Who speaks

with a forked tongue? Science 338: 1428-1429.

Maddision WP, Maddison DR. 2011. Mesquite: A Modu-

lar System for Evolutionary Analysis. Version 2.75.

Available: www.mesquiteproject.org [Accessed: 15

March 2013].

Mallett J. 1995. A species definition for the Modern Syn-

thesis. Trends in Ecology & Evolution 10: 294-299.

Martin PS, Yetman DA. 2000. Secrets of a tropical de-

ciduous forest. Pp. 4-18 In: The Tropical Deciduous

Forest of Alamos. Editors, Robichaux RH, Yetman

DA. The University of Arizona Press, Tucson, Ari-

zona, USA.

Martins EP. 1996. Phylogenies and the Comparative

Method in Animal Behavior. Oxford University Press,

New York, USA.

Miles L, Newton AC, DeFries DS, Ravilious C, May I,

Blyth S, Kapos V, Gordon JE. 2006. A global over-

view of the conservation status of tropical dry forests.

Journal of Biogeography 33: 491-505.

Minton SA, Weinstein SA. 1986. Geographic and onto-

genetic variation in venom of the western diamond-

back rattlesnake ( Crotalus atrox). Toxicon 71: 71-80.

Mittermeier TA, Turner WR, Larsen FW, Brooks TM,

Gascon C. 2011. Global biodiversity conservation:

the critical role of hotspots. Pp. 3-14 In: Biodiver-

sity Hotspots: Distribution and Protection of Con-

servation Priority Areas. Editors, Zachos, FE, Habe

JC. Springer- Verlag, Berlin, Germany.

Monroy-Vilchis O, Hernandez-Gallegos O, Rodrfguez-

Romero F. 2005. Heloderma horridum horridum

(Mexican beaded lizard). Unusual habitat. Herpeto-

logical Review 36: 450.

Myers N, Mittermeier RA, Mittermeier CG, da Fonseca

GAB, Kent J. 2000. Biodiversity hotspots for conser-

vation priorities. Nature 409: 853-858.

Najera Acevedo A. 2006. The conservation of thorn scmb

and dry forest habitat in the Motagua Valley, Guate-

mala: promoting the protection of a unique ecoregion.

Lyonia 9: 7-19.

Pennington RT, Lewis GP, Ratter JA. 2006. (Editors).

Neotropical Savannas and Seasonally Dry Forests:

Plant Diversity, Biogeography, and Conservation.

CRC Press, Boca Raton, Florida, USA.

Poe S, Wiens JJ. 2000. Character selection and method-

ology of morphological phylogenetics. Pp. 20-36 In:

Phylogenetic Analysis of Morphological Data. Editor,

Wiens JJ. Smithsonian Institution Press, Washington,

DC, USA.

Porras LW, Wilson LD, Schuett GW, Reiserer RS. 2013.

A taxonomic reevaluation and conservation assess-

ment of the common cantil, Agkistrodon bilineatus

(Squamata: Viperidae): a race against time. Amphib-

ian & Reptile Conservation 7(1): 48-73.

July 2013 | Volume 7 | Number 1 | e67

Amphib. Reptile Conserv. | http://amphibian-reptile-conservation.org

094

Taxonomy and conservation of beaded lizards

Pregill GK, Gauthier JA, Greene HW. 1986. The evolu-

tion of helodermatid squamates, with description of a

new taxon and an overview of Varanoidea. Transac-

tions of the San Diego Society of Natural History 21:

167-202.

Pyron RA, Burbrink FT, Wiens JJ. 2013. A phylogeny

and revised classification of Squamata, including

4151 species of lizards and snakes. BMC Evolution-

ary Biology 13: 93. [doi: 10. 11 86/147 1-2 148- 13-93].

Ramfrez-Velazquez, A. 2009. Monstruo horrible y vene-

noso, timido, apaciable ye en peligro de extinction.

Herpetofilos 1: 13-17.

Ree RH, Smith SA. 2008. Maximum likelihood infer-

ence of geographic range evolution by dispersal, local

extinction, and cladogenesis. Systematic Biology 57:

4-14.

Robichaux RH, Yetman DA. 2000. The tropical decidu-

ous forest of Alamos: biodiversity of a threatened eco-

system in Mexico. The University of Arizona Press,

Tucson, Arizona, USA.

Ronquist F. 1997. Dispersal-vicariance analysis: a new

approach to the quantification of historical biogeogra-

phy. Systematic Biology 46: 195-203.

Ronquist F. 2001. DIVA version 1.2 computer program

for MacOS ad Win 32. Available: www.ebc.uu.se/

systzoo/research/diva/diva.hyml [Accessed: 25 March

2013]. Evolutionary Biology Centre, Uppsala Univer-

sity, Sweden.

Sanchez- Azofeifa, GA, Quesada M, Rodriguez JP, Nas-

sar JM, Stoner KE, Castillo A, Garvin T, Zent EL,

Calvo-Alvarado JC, Kalacska, MER, Fajardo L,

Gamon JA, Cuevas-Reyes P. 2005. Research priorities

for Neotropical dry forests. Biotropica 37: 477-485.

Sanchez-De La Vega G, Buenrostro-Silva A, Garcfa-

Grajales J, Mata-Silva V. 2012. Geographic distribu-

tion. Heloderma horridum (Mexican beaded lizard).

Mexico: Oaxaca. Herpetological Review 43: 102.

Schuett GW, Gergus EWA, Kraus F. 2001. Phylogenetic

correlation between male-male fighting and mode of

prey subjugation in snakes. Acta Ethologica 4: 31-49.

Schuett GW, Reiserer RS, Earley RL. 2009. The evolu-

tion of bipedal postures in varanoid lizards. Biological

Journal of the Linnean Society 97: 652-663.

Schwalbe CR, Lowe CH. 2000. Amphibians and reptiles

of the Sierra de Alamos. Pp. 172-183 In: The Tropical

Deciduous Forest of Alamos: Biodiversity of a Threat-

ened Ecosystem in Mexico. Editors, Robichaux RH,

Yetman DA. The University of Arizona Press, Tucson,

Arizona, USA.

SEMARNAT. 2010. NORMA Oficial Mexicana NOM-

059-SEMARNAT-2010, Proteccion ambiental-Espe-

cies nativas de Mexico de flora y fauna silvestres-Cat-

egorfas de riesgo y especificaciones para su inclusion,

exclusion o cambio-Lista de especies en riesgo. Dia-

rio Oficial de la Federacion, 30 de dicembre, 2010.

Stoner KE, Sanchez- Azofeifa GA. 2009. Ecology and

regeneration of tropical dry forests in the Americas:

implications for management. Forest Ecology and

Management 258: 903-906.

Stuart LC. 1954. A description of a subhumid corridor

across northern Central America, with comments

on its herpetofaunal indicators. Contributions from

the Laboratory of Vertebrate Biology, University of

Michigan 65: 1-26.

Stuart LC. 1966. The environment of the Central Ameri-

can cold-blooded vertebrate. Copeia 1966: 684-699.

Sullivan BK, Kwiatkowski MA, Schuett GW. 2004.

Translocation of urban Gila monsters: a problematic

conservation tool. Biological Conservation 117: 235-

242.

Tobias JA, Seddon N, CN Spottiswoode, JD Pilgrim,

LDC Fishpool, and NJ Collar. 2010. Quantitative cri-

teria for species delimitation. Ibis 152: 724-746.

Townsend TM, Larson A, Louis E, Macey RJ. 2004.

Molecular phylogenetics of Squamata: the position of

snakes, amphisbaenians, and dibamids, and the root

of the squamate tree. Systematic Biology 53: 735-757.

Trejo I, Dirzo R. 2000. Deforestation of seasonally dry

tropical forest: a national and local analysis in Mexi-

co. Biological Conservation 94: 133-142.

Urbina-Cardona JN, Flores- Villela O. 2010. Ecological-

niche modeling and prioritization of conservation-

area networks for Mexican herpetofauna. Conserva-

tion Biology 24: 1031-1041.

Wiegmann AFA. 1829. Ueber das Acaltetepan oder

Temaculcachua des Hernandez, eine neue Gattung der

Saurer, Heloderma. Isis von Oken 22: 624-629.

Wiens JJ. 2004. The role of morphological data in phy-

logeny reconstruction. Systematic Biology 53: 659-

661. ”

Wiens JJ. 2008. Systematics and herpetology in the Age

of Genomics. BioScience 58: 297-307.

Wiens JJ, Kuczynski CA, Townsend TM, Reeder TW,

Mulcahy DG, and Sites JW. 2010. Combining phy-

logenomics and fossils in higher-level squamate rep-

tile phylogeny: molecular data change the placement

of fossile taxa. Systematic Biology 59: 674-688.

Wiens JJ, Hutter CR, Mulcahy DG, Noonan BP,

Townsend TM, Sites JW Jr, Reeder TW. 2012. Re-

solving the phylogeny of lizards and snakes (Squa-

mata) with extensive sampling of genes and species.

Biology Fetters 8: 1043-1046.

Wiley, EO. 1978. The evolutionary species concept re-

considered. Systematic Zoology 27: 17-26.

Willis KJ, Bailey RM, Bhagwat SA, and Birks HJB.

2010. Biodiversity baselines, thresholds and resil-

ience: testing predictions and assumptions using pa-

laeoecological data. Trends in Ecology & Evolution

25: 583-591.

Wilson EO, Brown WL. 1953. The subspecies concept

and its taxonomic application. Systematic Zoology 2:

97-111.

Wilson LD, Johnson JD. 2010. Distributional patterns

of the herpetofauna of Mesoamerica, a biodiversity

July 2013 | Volume 7 | Number 1 | e67

Amphib. Reptile Conserv. | http://amphibian-reptile-conservation.org

095

Reiserer et al.

hotspot. Pp. 30-255 In: Conservation of Mesoameri-

can Amphibians and Reptiles. Editors, Wilson LD,

Townsend JH, Johnson JD. Eagle Mountain Publish-

ing, LC, Eagle Mountain, Utah, USA.

Wilson LD, Mata-Silva V, Johnson JD. 2013. A conser-

vation reassessment of the reptiles of Mexico based

on the EVS measure. Amphibian & Reptile Conserva-

tion 7(1): 1-47.

Wilson LD, McCranie JR. 2004. The conservation status

of the herpetofauna of Honduras. Amphibian & Rep-

tile Conservation 3: 6-33.

Wilson, LD, Townsend JH, Johnson JD. 2010. Conser-

vation of Mesoamerican Amphibians and Reptiles.

Eagle Mountain Publishing, LC, Eagle Mountain,

Utah, USA.

Williams-Linera G, Lorea F. 2009. Tree species diversity

driven by environmental and anthropogenic factors

in tropical dry forest fragments in central Veracruz,

Mexico. Biodiversity and Conservation 18: 3269-

3293.

Zink RM. 2004. The role of subspecies in obscuring avi-

an biological diversity and misleading conservation

policy. Proceedings of the Royal Society of London B

271: 561-564.

Received: 23 May 2013

Accepted: 12 June 2013

Published: 29 July 2013

Randall S. Reiserer is an integrative biologist whose research focuses on understanding the interrelationships

among ecology, morphology, and behavior. Within the broad framework of evolutionary biology, he studies

cognition, neuroscience, mimicry, life-history evolution, and the influence of niche dynamics on patterns of

evolutionary change. His primary research centers on reptiles and amphibians, but his academic interests

span all major vertebrate groups. His studies of behavior are varied and range from caudal luring and themial

behavior in rattlesnakes to learning and memory in transgenic mice. Randall established methods for study-

ing visual perception and stimulus control in is studies of caudal luring in snakes. He commonly employs

phylogenetic comparative methods and statistics to investigate and test evolutionary patterns and adaptive

hypotheses. Dr. Reiserer is an editor of the upcoming peer-reviewed book, The Rattlesnakes of Arizona.

Gordon W. Schuett is an evolutionary biologist and herpetologist who has conducted extensive research on rep-

tiles. His work has focused primarily on venomous snakes, but he has also published on turtles, lizards, and

amphibians. Among his most significant contributions are studies of winner-loser effects in agonistic encoun-

ters, mate competition, mating system theory, hormone cycles and reproduction, caudal luring and mimicry,

long-term sperm storage, phylogeographic analyses of North American pitvipers, and as a co-discoverer of

facultative parthenogenesis in non-avian reptiles. He served as chief editor of the peer-reviewed book Biology

of the Vipers and is presently serving as chief editor of an upcoming peer-reviewed book The Rattlesnakes of

Arizona (rattlesnakesofarizona.org). Gordon is a Director and scientific board member of the newly founded

non-profit The Copperhead Institute (copperheadinstitute.org). He was the founding Editor of the journal

Herpetological Natural History. Dr. Schuett resides in Arizona and is an adjunct professor in the Department

of Biology at Georgia State University.

Daniel D. Beck is an ecologist and herpetologist who has conducted research on the ecology, physiology, and be-

havior of rattlesnakes and helodermatid lizards. He has pioneered many of the field studies on helodermatid

lizards in the past 30 years, including topics ranging from energy metabolism and habitat use to combat and

foraging behaviors in locations ranging from the deserts of Utah, Arizona, and New Mexico, to the tropical

dry forests of Sonora and Jalisco, Mexico. His book, Biology of Gila Monsters and Beaded Lizards (2005),

presents a synthesis of much of our knowledge of these charismatic reptiles. Dr. Beck is Professor of Biology

at Central Washington University, in Ellensburg, Washington, where he lives in a straw bale house with his

wife, biologist Kris Ernest, and their two teenage children.

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096

Pseudoeurycea naucampatepetl. The Cofre de Perote salamander is endemic to the Sierra Madre Oriental of eastern Mexico. This

relatively large salamander (reported to attain a total length of 150 mm) is recorded only from, “a narrow ridge extending east from

Cofre de Perote and terminating [on] a small peak (Cerro Volcancillo) at the type locality,” in central Veracruz, at elevations from

2,500 to 3,000 m (Amphibian Species of the World website). Pseudoeurycea naucampatepetl has been assigned to the P. bellii

complex of the P. bellii group (Raffaelli 2007) and is considered most closely related to P gigantea, a species endemic to the La

Joya-Jalapa region of Veracruz and adjacent northeastern Hidalgo (Parra-Olea et al. 2001). This salamander is known from only five

specimens and has not been seen for 20 years, despite thorough surveys in 2003 and 2004 (EDGE; www.edgeofexistence.org), and

thus it might be extinct. The habitat at the type locality (pine-oak forest with abundant bunch grass) lies within Lower Montane Wet

Forest (Wilson and Johnson 2010; IUCN Red List website [accessed 21 April 2013]). The known specimens were “found beneath

the surface of roadside banks” (www.edgeofexistence.org) along the road to Las Lajas Microwave Station, 15 kilometers (by road)

south of Highway 140 from Las Vigas, Veracruz (Amphibian Species of the World website). This species is terrestrial and presumed

to reproduce by direct development.

Pseudoeurycea naucampatepetl is placed as number 89 in the top 100 Evolutionarily Distinct and Globally Endangered amphib-

ians (EDGE; www.edgeofexistence.org). We calculated this animal’s EVS as 17, which is in the middle of the high vulnerability

category (see text for explanation), and its IUCN status has been assessed as Critically Endangered. Of the 52 species in the genus

Pseudoeurycea, all but four are endemic to Mexico (see Appendix of this paper and Acevedo et al. 2010). Photo by James Hanken.

August 2013 | Volume 7 | Number 1

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http://amphibian-reptile-conservation.org

97

e69

mons Attribution-NonCommercial-NoDerivs 3.0 Unported License, which permits unrestricted use for non-com-

mercial and education purposes only provided the original author and source are credited.

Amphibian & Reptile Conservation 7(1): 97-127.

A conservation reassessment of the amphibians of

Mexico based on the EVS measure

^arry David Wilson, 2 Jerry D. Johnson, and 3 Vicente Mata-Silva

1 Centro Zamorano de Biodiversidad, Escuela Agricola Panamericana Zamorano, Departamento de Francisco Morazdn, HONDURAS ^Depart-

ment of Biological Sciences, The University of Texas at El Paso, El Paso, Texas 79968-0500, USA

Abstract . — Global amphibian population decline is one of the better documented symptoms of bio-

diversity loss on our planet, and one of the environmental super-problems humans have created.

Most people believe that we should manage nature for our benefit, instead of understanding that

we are part of the natural world and depend on it for our survival. As a consequence, humans keep

unraveling Earth’s life-support systems, and to reverse this trend must begin to develop a sustain-

able existence. Given this reality, we examine the conservation status of the 378 species of amphib-

ians in Mexico, by using the Environmental Vulnerability Score (EVS) algorithm. We summarize and

critique the IUCN Red List Assessments for these creatures, calculate their EVS, and compare the

results of both conservation assessments. We also compare the EVS for Mexican amphibians with

those recently reported for Mexican reptiles, and conclude that both groups are highly imperiled,

especially the salamanders, lizards, and turtles. The response of humans to these global impera-

tives has been lackluster, even though biological scientists worldwide have called attention to the

grave prospects for the survival of life on our planet. As part of the global community, Mexico must

realize the effects of these developments and the rapid, comprehensive need to conserve the coun-

try’s hugely significant herpetofauna. Based on this objective, we provide five broad-based recom-

mendations.

Key words. EVS, anurans, salamanders, caecilians, IUCN categorizations, survival prospects

Resumen . — La disminucion global de las poblaciones de anfibios es uno de los sintornas mas docu-

mentados sobre la perdida de biodiversidad en nuestro planeta, que a su vez es uno de los super-

problemas ambientales creados por los seres humanos. La mayoria de los seres humanos creemos

que podemos y debemos manejar la naturaleza para nuestro propio beneficio, en lugar de compren-

der que somos parte y dependemos de ella misma. Como consecuencia de ello, estamos desarticu-

lando los sistemas biologicos del planeta, y para revertir esta tendencia debemos desarrollar una

existencia sostenible. Ante esta realidad, examinamos el estado de conservacion de las 378 espe-

cies de anfibios mexicanos utilizando el algoritmo de Medida de Vulnerabilidad Ambiental (EVS).

Resumimos y criticamos las evaluaciones de la Lista Roja para estos organismos, calculamos su

EVS, y comparamos los resultados con los resultados de la categorizacion de la UICN. Tambien

comparamos el EVS de los anfibios mexicanos con los publicados recientemente para los reptiles

de Mexico, concluyendo que ambos grupos estan en un peligro altamente significativo, principal-

mente las salamandras, las lagartijas y las tortugas. La respuesta humana a esta crisis global ha

sido mediocre, a pesar de que la comunidad mundial de biologos se une al llamado de atencion

sobre las perspectivas graves que amenazan la supervivencia de la vida en nuestro planeta. Como

parte de la comunidad mundial, el pais de Mexico debe de considerar los efectos de estos cambios,

y la rapida necesidad de conservar de manera integral la herpetofauna altamente significativa de

este pais. Basandonos en este objetivo, proporcionamos cinco recomendaciones generalizadas.

Palabras claves. EVS, anuros, salamandras, cecilios, categorizacion de UICN, perspectivas de supervivencia

Citation: Wilson LD, Johnson JD, Mata-Silva V. 2013. A conservation reassessment of the amphibians of Mexico based on the EVS measure. Amphibian

& Reptile Conservation 7(1): 97-127(e69).

Correspondence. Emails: 1 bufodoc@aol.com (Corresponding author) 2 jjohnson@utep.edu 3 vmata@ utep.edu

August 2013 | Volume 7 | Number 1 | e69

Amphib. Reptile Conserv. | http://amphibian-reptile-conservation.org gs

Wilson et al.

How will humans react to an increased awareness that

Earth’s biodiversity is diminishing? What are these loss-

es telling us about our place on the planet, our role in the

biosphere? What is our role in conserving biodiversity as

we become custodians of a planet that has clear limita-

tions ? And how can we pass to future generations the

wisdom needed to make sound environmental decisions?

The answers to these questions will tell us much about

ourselves, and science will take us only part of the way

along that journey.

Collins and Crump 2009: 205.

Introduction

Global amphibian population decline is a well-known

environmental issue to conservation biologists and her-

petologists (Collins and Crump 2009; Stuart et al. 2010).

This issue, however, often does not make it onto lists

of the world’s most significant problems. A survey of

European Union citizens conducted in the fall of 2011

identified the following problems of greatest concern:

(1) poverty, hunger and lack of drinking water (28% of

those surveyed); (2) climate change (20%); (3) the eco-

nomic situation (16%); (4) international terrorism (11%);

(5) the availability of energy (7%); (6) the increasing

global population (5%); (7) the spread of infectious dis-

ease (4%); (8) armed conflict (4%); the proliferation of

nuclear weapons (3%); and (10) don’t know (2%).

Such surveys expose several underlying concerns.

One is that amphibian population decline is not on the

list, but neither is the larger issue of biodiversity decline.

Another concern is that this “pick the biggest problem”

approach does not acknowledge that all of these issues

are intertwined and capable of creating “environmental

super-problems,” as explained by Bright (2000). Further,

with respect to the natural world Bright (2000: 37) indi-

cated that “we will never understand it completely, it will

not do our bidding for free, and we cannot put it back the

way it was.” These features are characteristic of biodiver-

sity and biodiversity decline, and indicative of how little

we know about the current status of biodiversity. Mora

et al. (2011) provided an estimate of the total amount of

biodiversity, which they indicated at approximately 8.7

million (±1.3 mill ion SE), with about 86% of the existing

land species and 91% of the oceanic species still await-

ing description. The description of new taxa is only the

initial step toward understanding how the natural world

works. The world will not do our bidding for free, since

we cannot obtain an appreciable quantity of anything

from nature without sacrificing something in the process.

In transforming our planet to fill the needs of our species,

we have destroyed the habitats of countless creatures (in-

cluding amphibians) that also have evolved over time.

We cannot reverse this damage, as evidenced by the fact

that we have been unable to provide permanent solutions

to any of the significant environmental problems. Such is

Amphib. Reptile Conserv. | http://amphibian-reptile-conservation.org 99

the case with biodiversity decline, since no retreat from

species extinction is possible.

Biodiversity decline is an environmental super-prob-

lem, as contributing factors include habitat modification,

fragmentation, and loss, pollution and disease, over-har-

vesting, exotic species, and extinction (Vitt and Caldwell

2009). These problems interact to enmesh species into

an extinction vortex, defined as “a downward population

spiral in which inbreeding and genetic drift combine to

cause a small population to shrink and, unless the spiral

is reversed, to become extinct” (Campbell et al. 2008:

1251). Theoretically, this effect should significantly im-

pact species with narrower distributions.

The extent of biodiversity decline is unknown, al-

though most estimates indicate that we know very little

about this topic. With respect to animals, we know sub-

stantially more about the diversity of vertebrates than in-

vertebrates. Among the vertebrates subjected to a global

analysis, a greater proportion of amphibians have been

documented as threatened than birds or mammals (Stuart

et al. 2010). Reptiles and fishes, however, remain unas-

sessed.

The data presented in Stuart et al. (2010) essentially

were the same as in Stuart (2004). The number of am-

phibians known globally now exceeds 7,000 (7,139;

www.amphibiaweb.org [accessed 8 June 2013]), which

is 24.3% greater than the one cited by Stuart et al. (2010).

The description of new species of amphibians obviously

is a “growth industry,” and the rate of discovery does not

appear to be slowing. Thus, we expect that the number

of new amphibian taxa from Mexico will continue to in-

crease.

Another major fault with assessing the “world’s great-

est problems” is that their causes are not identified. As

noted by Wilson et al. (2013: 23), “no permanent solution

to the problem of biodiversity decline (including herpe-

tofaunal decline) will be found in Mexico (or elsewhere

in the world) until humans recognize overpopulation as

the major cause of degradation and loss of humankind’s

fellow organisms.” Further, they stated (Pp. 23-24) that,

“solutions will not be available until humanity begins to

realize the origin, nature, and consequences of the mis-

match between human worldviews and how our planet

functions.” Miller and Spoolman (2012: 20) defined this

“planetary management worldview” as maintaining that

“we are separate from and in charge of nature, that nature

exists mainly to meet our needs and increasing wants,

and that we can use our ingenuity and technology to

manage the earth’s life-support systems, mostly for our

benefit, into the distant future.”

Unfortunately, over the span of about 10,000 years,

humans have dismantled the planet’s life-support sys-

tems, and today we are living unsustainably (Miller and

Spoolman 2012). So, until and unless we develop an en-

vironmentally sustainable society, no lasting, workable

solutions to environmental problems will be found, in-

cluding that of biodiversity decline.

August 2013 | Volume 7 | Number 1 | e69

Conservation reassessment of Mexican amphibians

Incilius pisinnus. The Michoacan toad, a state endemic, is known only from the Tepalcatepec Depression. This toad’s EVS has

been assessed as 15, placing it in the lower portion of the high vulnerability category, and its IUCN status as Data Deficient. This

individual came from Apatzingan. Photo by Ivan Trinidad Ahumada- Carrillo.

Craugastor hobartsmithi. The distribution of the endemic Smith’s pygmy robber frog is along the southwestern portion of the Mexi-

can Plateau, from Nayarit and Jalisco to Michoacan and the state of Mexico. Its EVS has been determined as 15, placing it in the

lower portion of the high vulnerability category, and its IUCN status as Endangered. This individual is from the Sierra de Manantlan

in Jalisco. Photo by Ivan Trinidad Ahumada-Carrillo.

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Wilson et al.

Nonetheless, building a sustainable society requires

steps that only a few people appear willing to take. Thus,

efforts by conservation biologists to reverse biodiversity

decline, including amphibian population decline, must

proceed with the realization that we will only be design-

ing short-term solutions that deal with the symptoms of

the problems rather than their causes. Within this real-

ization, we undertake the following reassessment of the

conservation status of the amphibians of Mexico.

A Revised Environmental Vulnerability

Measure

In conducting a conservation reassessment of Mexican

reptiles, Wilson et al. (2013) revised the Environmen-

tal Vulnerability Score (EVS) from that used in various

chapters of Wilson et al. (2010). Similarly, we modified

the EVS measure for use with Mexican amphibians, es-

pecially by substituting the human persecution scale used

for reptiles with a reproductive mode scale, as did Wilson

and McCranie (2004) and other authors who used this

measure with Central American amphibians (see Wilson

et al. 2010).

Wilson et al. (2013) indicated that the EVS measure

originally was designed for use in cases where the details

of the population status of a species, upon which many

of the criteria for IUCN status categorization depend,

were not available, as well as to provide an estimate of

the susceptibility of amphibians and reptiles to future en-

vironmental threats. The advantages for using the EVS

measure are indicated below (see EVS for Mexican am-

phibians).

The EVS algorithm we developed for use with Mexi-

can amphibians consists of three scales, for which the

values are added to produce the Environmental Vulner-

ability Score. The first scale deals with geographic distri-

bution, as follows:

1 = distribution broadly represented both inside and

outside Mexico (large portions of range are both

inside and outside Mexico)

2 = distribution prevalent inside Mexico, but limited

outside Mexico (most of range is inside Mexico)

3 = distribution limited inside Mexico, but prevalent

outside Mexico (most of range is outside Mex-

ico)

4 = distribution limited both inside and outside Mexi-

co (most of range is marginal to areas near bor-

der of Mexico and the United States or Central

America)

5 = distribution within Mexico only, but not restricted

to vicinity of type locality

6 = distribution limited to Mexico in the vicinity of

type locality

Amphib. Reptile Conserv. | http://amphibian-reptile-conservation.org 101

The second scale deals with ecological distribution, as

follows:

1 = occurs in eight or more formations

2 = occurs in seven formations

3 = occurs in six formations

4 = occurs in five formations

5 = occurs in four formations

6 = occurs in three formations

7 = occurs in two formations

8 = occurs in one formation

The third scale is concerned with the type of reproductive

mode, as follows:

1 = both eggs and tadpoles in large to small bodies of

lentic or lotic water

2 = eggs in foam nests, tadpoles in small bodies of

lentic or lotic water

3 = tadpoles occur in small bodies of lentic or lotic

water, eggs outside of water

4 = eggs laid in moist situation on land or moist ar-

boreal situations, direct development, or vivipa-

rous

5 = eggs and tadpoles in water-retaining arboreal bro-

meliads or water-filled tree cavities

Once these three components are added, their EVS can

range from 3 to 19. Wilson and McCranie (2004) allo-

cated the range of scores for Honduran amphibians into

three categories of vulnerability to environmental degra-

dation, as follows: low (3-9); medium (10-13); and high

(14-19). We use the same categorization.

Recent Changes to the Mexican Amphibian

Fauna

Our knowledge of the composition of the Mexican am-

phibian fauna keeps changing due to discovery of new

species and the systematic adjustment of certain known

species, which adds or subtracts from the list of taxa that

appeared in Wilson et al. (2010). Since that time, the fol-

lowing seven species have been described or resurrected:

Incilius aurarius: Mendelson et al. 2012. Journal of

Herpetology 46: 473-479. New species.

Incilius mccoyi : Santos-Barrera and Flores Villela.

2011. Journal of Herpetology 45: 211-215. New spe-

cies.

Craugastor saltator: Hedges et al. 2008. Zootaxa

1737: 1-182. Resurrected from synonymy of C. mexi-

canus.

August 2013 | Volume 7 | Number 1 | e69

Conservation reassessment of Mexican amphibians

Eleutherodactylus modestus. The endemic blunt-toed chirping frog is known from Colima and southwestern Jalisco. Its EVS has

been calculated at 16, placing it in the middle portion of the high vulnerability category, and its IUCN status as Vulnerable. This

individual is from the Sierra de Manantlan in Jalisco. Photo by Ivan Trinidad Ahumada- Carrillo.

Dendropsophus sartori. The endemic Taylor’s yellow treefrog is distributed along the Pacific slopes from Jalisco to Oaxaca. Its

EVS has been determined as 14, at the lower end of the high vulnerability category, and its IUCN status as of Least Concern. This

individual came from the Municipality of Minatitlan, Colima. Photo by Jacobo Reyes-Velasco.

Amphib. Reptile Conserv. | http://amphibian-reptile-conservation.org 102

August 2013 | Volume 7 | Number 1 | e69

Wilson et al.

Charadrahyla tecuani: Campbell et al. 2009. Copeia

2009: 287-295. New species.

Gastrophryne mazatlanensis : Streicher et al. 2012.

Molecular Phylogenetics and Evolution 64: 645-653.

Resurrected from synonymy of G. olivacea.

Bolitoglossa chinanteca : Rovito et al. 2012. ZooKeys

185: 55-71. New species.

Pseudoeurycea cafetalera : Parra-Olea et al. 2010.

Zootaxa 2725: 57-68. New species.

This represents an increase of 2.0% over the 373 species

listed by Wilson and Johnson (2010).

The following species have undergone status changes,

and include some taxa discussed in the addendum to Wil-

son and Johnson (2010):

Diaglena spatulata: Smith et al. 2007. Evolution 61:

2075-2085. Transfer from genus Triprion.

Hypopachus ustus : Streicher et al. 2012. Molecular

Phylogenetics and Evolution 64: 645-653. Transfer

from genus Gastrophryne. Spelling of specific epithet

corrected by Frost (2013).

Trachycephalus typhonius : Lavilla et al. 2010. Zoo-

taxa 2671: 17-30. New name for T. venulosus.

Ixalotriton niger : Wake. 2012. Zootaxa 3484: 75-82.

Resurrection of genus.

Ixalotriton parva: Wake. 2012. Zootaxa 3484: 75-82.

Resurrection of genus.

IUCN Red List Assessment of Mexican

Amphibians

The IUCN assessment of Mexican amphibians was con-

ducted as part of a Mesoamerican Workshop held in 2002

at the La Selva Biological Station in Costa Rica (see fore-

word in Kohler 2011). The results of this workshop were

incorporated into a general worldwide overview called

the Global Amphibian Assessment (Stuart et al. 2004;

Stuart et al. 2008; Stuart et al. 2010). This overview un-

covered startling conclusions, of which the most impor-

tant was that nearly one-third (32.3%) of the world’s am-

phibian species are threatened with extinction, i.e., were

assessed as Critically Endangered, Endangered, or Vul-

nerable. This proportion did not include 35 species con-

sidered as Extinct or Extinct in the Wild, and by adding

them 1,891 of 5,743 species (32.9%) were considered as

Table 1 . IUCN Red List categorizations for Mexican amphibian families.

Number of

species

IUCN Red List categorizations

Families

Critically

Endangered

Vulnerable

Near

Threatened

Least

Concern

Data

Deficient

Not

Evaluated

Bufonidae

35

1

7

2

3

19

1

2

Centrolenidae

1

—

1

—

Craugastoridae

39

7

8

7

3

6

2

Eleutherodactylidae

23

2

4

7

—

4

5

1

Hylidae

97

29

18

10

4

25

8

3

Leiuperidae

1

—

1

—

Leptodactylidae

2

—

2

—

Microhylidae

6

—

1

—

4

—

1

Ranidae

28

4

2

5

2

12

2

1

Rhinophrynidae

1

—

1

—

Scaphiopodidae

4

—

2

—

2

Subtotals

237

43

39

31

12

77

22

12

Ambystomatidae

18

9

2

—

2

3

2

Plethodontidae

118

36

37

11

9

10

12

3

Salamandridae

1

—

1

—

Sirenidae

2

—

2

—

Subtotals

139

45

40

11

9

14

15

5

Dermophiidae

2

—

1

—

1

—

Subtotals

2

—

1

—

1

—

Totals

378

88

79

44

21

91

38

17

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Conservation reassessment of Mexican amphibians

Smilisca dentata. The endemic upland burrowing treefrog occurs only in southwestern Aguascalientes and adjacent northern Jalisco.

Its EVS has been assessed as 14, placing it at the lower end of the high vulnerability category, and its IUCN status as Endangered.

This individual was found in the Municipality of Ixtlahuacan del Rio, Jalisco. Photo by Jacobo Reyes-Velasco.

Lithobates johni. Moore’s frog is an endemic anuran whose distribution is limited to southeastern San Luis Potosf, eastern Hidalgo,

and northern Puebla. Its EVS has been assessed as 14, placing it at the lower end of the high vulnerability category, and its IUCN

status as Endangered. This individual came from Rio Claro, Municipality of Molango, Hidalgo. Photo by Uriel Hernandez- Salinas.

August 2013 | Volume 7 | Number 1 | e69

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Wilson et al.

threatened, near extinction, or extinct. Notably, another

1,290 species (22.5%) were evaluated as Data Deficient,

i.e., too poorly known to allocate to any of the other

IUCN categories. By adding these species to the previous

figure of 1,891, an astonishing amount of amphibian spe-

cies (3,181 [55.4%]) known at that time were considered

threatened, near extinction, extinct, or too poorly known

to assess. These horrific pronouncements gave rise to a

worldwide cottage industry that continues to evaluate the

state of amphibian population decline, as registered in

a number of websites, most prominently AmphibiaWeb

and the Global Amphibian Assessment.

The IUCN Red List website lists the current catego-

rizations for the world’s amphibians using the standard

IUCN system. We accessed this website in order to sum-

marize the current situation for Mexican amphibians

(Table 1). The data in this table are more complete than

those for reptiles, as reported by Wilson et al. (2013). All

but 17 of the current 378 known Mexican amphibian spe-

cies have been assigned to an IUCN category, and as for

the reptiles (see Wilson et al. 2013) we placed these 17

amphibian taxa (4.5%) in a Not Evaluated (NE) category.

The remaining categorizations are: Critically Endangered

(CR; 88; 23.2%); Endangered (EN; 79; 20.8%); Vulner-

able (VU; 44; 11.6%); Near Threatened (NT; 21; 5.5%);

Least Concern (LC; 92; 24.2%); and Data Deficient (DD;

38; 10.0%). Thus, 211 species (55.7%) are placed in one

of the three threat categories (CR, EN, or VU), a propor-

tion significantly higher from that reported for these cat-

egories on a global scale (CR+EN+VU = 1,856 species,

32.3%; Stuart et al., 2010). If the DD species are added to

those in the threat categories, then 249 (65.7%) are either

threatened with extinction or too poorly known to allow

for assessment, a proportion significantly beyond that for

the global situation (CR+EN+VU+DD = 3,146 species;

54.8%; Stuart et al. 2010).

The largest proportion of threatened species are in

the anuran families Craugastoridae (22 of 39 species;

56.4%), Eleutherodactylidae (13 of 24 species; 54.2%),

and Hylidae (57 of 97 species; 58.8%), and the salaman-

der families Ambystomatidae (11 of 19 species; 57.9%)

and Plethodontidae (84 of 118 species; 71.2%). Collec-

tively, the 297 species in these five families make up

78.4% of the amphibian taxa in Mexico, and the 187

threatened species in these families comprise 88.6% of

the 211 total.

Table 2. Environmental Vulnerability Scores for Mexican amphibian species, arranged by family. Shaded area to left encompasses low vul-

nerability scores, and to the right high vulnerability scores.

Families , Environmental Vulnerability Scores

of species J

3

4

5

6

7

8

9

10

11

12

13

14

15

16

17

18

19

Bufonidae

35

1

—

1

2

3

2

6

4

5

2

—

Centrolenidae

1

Craugastoridae

39

—

1

4

10

3

5

8

—

Eleutherodactylidae

23

2

3

—

3

4

8

3

—

Hylidae

97

1

2

—

4

7

5

9

11

16

22

12

1

Leiuperidae

1

Leptodactylidae

2

—

1

—

Microhylidae

6

—

1

—

1

2

1

Ranidae

28

1

—

1

—

1

2

5

4

5

3

—

Rhinophrynidae

1

Scaphiopodidae

4

1

—

1

—

1

—

1

—

Subtotals

237

4

3

4

9

12

14

13

20

25

29

36

30

8

14

12

1

Subtotals %

—

1.7

1.3

1.7

3.8

5.1

5.9

5.4

8.4

10.5

12.2

15.2

12.7

3.4

5.9

5.1

0.4

Ambystomatidae

18

—

2

—

4

5

7

—

Plethodontidae

118

—

1

—

2

3

8

16

13

36

—

Salamandridae

1

Sirenidae

2

—

2

—

Subtotals

139

—

1

2

6

7

13

23

13

36

—

Subtotals %

—

0.7

1.4

4.3

5.0

9.4

16.6

9.4

25.9

—

Dermophiidae

2

1

—

Subtotals

2

1

—

Subtotals %

—

50.0

—

Totals

378

4

3

4

9

12

15

23

32

36

49

53

21

50

48

1

Totals %

—

1.1

0.8

1.1

2.3

3.2

4.0

6.1

8.4

9.5

12.9

14.0

5.6

13.2

12.7

0.3

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Conservation reassessment of Mexican amphibians

Triprion petasatus. The Yucatecan casque-headed treefrog is restricted primarily to the Yucatan Peninsula, occurring in the Mexican

states of Yucatan, Campeche, and Quintana Roo, as well as in northern Guatemala and northern Belize. A disjunct population also

has been recorded from Santa Elena, Departamento de Cortes, Honduras. Its EVS has been calculated as 10, placing it at the lower

end of the medium vulnerability category, and its IUCN status is of Least Concern. Although this treefrog is broadly distributed in

the Yucatan Peninsula, it usually is found only during the rainy season when males and females congregate around restricted bodies

of water (solution pits, cenotes, and ephemeral ponds) on this flat limestone platform. During the dry season, these frogs retreat into

tree holes and rock crevices, and sometimes use their head to plug the opening. This individual is from the state of Yucatan. Photo

by Ed Cassano.

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Wilson et al.

These data from the IUCN Red List show a frighten-

ing picture for the amphibian fauna of Mexico, acknowl-

edged as a major herpetodiversity hotspot in the world

on the basis of its diversity and endemism (Wilson and

Johnson 2010). Mexico’s level of amphibian endemism

(66.8%) also has been reported as greater than that for

the country’s reptiles (57.2%; Wilson and Johnson 2010).

Even more frightening is the fact that Mexican salaman-

ders are more threatened than anurans (Table 1). Of the

139 recognized species of salamanders, 96 (69.1%) were

assessed into one of the threat categories, as compared

to anurans (114 of 236 [48.3%]). In addition, a much

smaller proportion of salamander species were judged as

Least Concern (14 [10.1%]), as compared to anurans (78

[33.1%]).

Critique of the IUCN Assessment

Although the conservation status of amphibians in Mex-

ico is better understood than that for reptiles (see Wil-

son et al. 2013), a need for reassessment still is required

for several reasons. About 10% of Mexico’s amphib-

ians have been judged as Data Deficient, and thus their

conservation status remains undetermined. In addition,

because certain species have been described recently

(see above), 4.5% have not been evaluated (see www.

iucnredlist.org; accessed 08 May 2013). Also, by adding

the DD and NE species, 55 (14.5%) of Mexico’s amphib-

ians presently are not assigned to any of the other IUCN

categories. Thus, we consider it worthwhile to subject the

Mexican amphibians to the same assessment measure ap-

plied by Wilson et al. (2013) for reptiles, to allow for a

comparison between these two groups. For these reasons,

we will reassess the Mexican amphibian fauna using the

Environmental Vulnerability Score (EVS).

EVS for Mexican Amphibians

The EVS provides several advantages for assessing the

conservation status of amphibians and reptiles. First, this

measure can be applied as soon as a species is named,

because the information necessary for its application

generally is known at that point. Second, calculating the

EVS is economical because it does not require expen-

sive, grant- supported workshops, such as those undertak-

en for the Global Amphibian Assessment (sponsored by

the IUCN). Third, the EVS is predictive, as it measures

susceptibility to anthropogenic pressure and can pinpoint

taxa with the greatest need of immediate attention and

continued scrutiny. Finally, it is simple to calculate and

does not “penalize” poorly known species. Thus, given

the geometric pace at which environmental threats wors-

en, since they are commensurate with the rate of human

population growth, it is important to use a conservation

assessment measure that can be applied simply, quickly,

and economically.

Amphib. Reptile Conserv. | http://amphibian-reptile-conservation.org 107

We calculated the EVS using the above-mentioned

methodology. This step allowed us to determine the con-

servation status of all the currently recognized Mexican

amphibian species (378), including the 55 species placed

in the DD category or not evaluated by the IUCN (www.

iucnredlist.org; see Appendix 1, Table 2).

Theoretically, the EVS can range from 3 to 20 (in

Mexico, from 3 to 19). A score of 3 is indicative of a spe-

cies that ranges widely both within and outside of Mexi-

co, occupies eight or more forest formations, and lays its

eggs in small to large lentic or lotic bodies of water. Four

such species (one each in the families Bufonidae, Hyli-

dae, Ranidae, and Scaphiopodidae) are found in Mexico.

At the other extreme, a score of 20 relates to a species

that is known only from the vicinity of the type locality,

occupies a single forest formation, and its eggs and tad-

poles are found in water-retaining arboreal bromeliads or

water-filled tree cavities (no such species occur in Mex-

ico). Thus, all the scores fall within the range of 4-19.

In the Introduction, we expressed an interest in at-

tempting to determine the impact of small populations

on amphibian species survival in Mexico. The data in

Appendix 1 allow us to approximate an answer to this

question, inasmuch as one of the components of the EVS

assesses the extent of geographic distribution on a sliding

scale (1-6), on which higher numbers signify increas-

ingly smaller geographic ranges. Using this range, the

distribution of the 378 Mexican species is as follows: 1 =

13 species (3.4%); 2 = 20 (5.3%); 3 = 28 (7.4%); 4 = 64

(16.9%); 5 = 126 (33.3%); and 6 = 127 (33.6%). Obvi-

ously, the higher the value of the geographic range, the

higher the number and percentage of the taxa involved.

These figures indicate that about one-third of the amphib-

ian species in Mexico are known only from the vicinity

of their respective type localities. The range of another

one-third is somewhat broader, but still limited to the

confines of Mexico. As a consequence, the survival pros-

pects of about two-thirds of Mexico’s amphibians are

tied to changes in their natural environment, as well as to

the conservation atmosphere in this nation.

We summarized the EVS for Mexican amphibians by

family in Table 2. The EVS range falls into the follow-

ing three portions: low (3-9), medium (10-13), and high

(14-19).

The range and average EVS for the major amphib-

ian groups are as follows: anurans = 3-19 (12.4); sala-

manders = 9-18 (15.9); and caecilians = 11-12 (11.5).

Salamanders generally are significantly more susceptible

than anurans to environmental degradation and caeci-

lians somewhat less susceptible than anurans (although

only two caecilian species are involved). The average

scores either fall in the medium category, in the case of

anurans and caecilians, or in the middle portion of the

high category, in the case of salamanders. The average

EVS for all amphibian species is 13.7, a value near the

lower end of the high range of vulnerability.

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Conservation reassessment of Mexican amphibians

Ambystoma velasci. The endemic Plateau tiger salamander, as currently recognized, is distributed widely from northwestern Chi-

huahua southward along the eastern slopes of the Sierra Madre Oriental, and from southern Nuevo Leon in the Sierra Madre Ori-

ental, westward to Zacatecas and southward onto the Transverse Volcanic Axis of central Mexico. Its EVS has been determined

as 10, placing it at the lower end of the medium vulnerability category, and its IUCN status is of Least Concern. Even though this

species does not appear threatened, this is likely an artifact of the composite nature of this taxon. This individual was found at Santa

Cantarina, Hidalgo. Photo by Raciel Cruz-Elizalde.

Bolitoglossa frcinklini. Franklin’s salamander is distributed along Pacific slopes from southern Chiapas, Mexico, southeastward to

south-central Guatemala. Its EVS has been determined as 14, placing it at the lower end of the high vulnerability category, and its

IUCN status as Endangered. This individual came from Cerro Mototal, in the Municipality of Motozintla, Chiapas. Photo by Sean

M. Rovito.

August 2013 | Volume 7 | Number 1 | e69

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Wilson et al.

An EVS of 14, at the lower end of the high vulnerabil-

ity category, was found in the highest percentage (15.2)

of anuran species. For salamanders, the respective values

are 25.9% for an EVS of both 17 and 18, near the upper

end of the range for the high vulnerability category, and

for caecilians 50.0% for an EVS of both 11 and 12.

The total EVS scores generally increased from the

low end of the scale (3) through most of the high end

(14-18), with a single exception (a decrease from 53 to

21 species at scores 15 and 16). An EVS of 15 was found

in the peak number of taxa (53), a score that falls within

the high range of vulnerability.

Of the 378 total taxa, 50 (13.2%) fall into the low

vulnerability category, 106 (28.0%) into the medium

category, and 222 (58.7%) into the high category. Thus,

six of every 10 Mexican amphibian species were judged

as having the highest degree of vulnerability to environ-

mental degradation, and slightly more than one-seventh

the lowest degree.

This considerable increase in the absolute and rela-

tive numbers from the low portion, through the medium

portion, to the high portion differs somewhat from the

results published for amphibians and reptiles for sev-

eral Central American countries in Wilson et al. (2010).

Acevedo et al. (2010) reported 89 species (23.2%) with

low scores, 179 (46.7%) with medium scores, and 115

(30.0%) with high scores for Guatemala. The same trend

was reported for Honduras, where Townsend and Wilson

(2010) indicated the corresponding values for amphib-

ians and reptiles as 71 (19.7%), 169 (46.8%), and 121

(33.5%). The comparable data for the Panamanian her-

petofauna in Jaramillo et al. (2010) are 143 (33.3%), 165

(38.4%), and 122 (28.4%).

The principal reason that EVS scores are relatively

high in Mexico is because of the high level of endemism

and the concomitantly narrow range of geographical and

ecological occurrence (Appendix 1). Of the 253 endemic

amphibian species (139 anurans, 113 salamanders, and

one caecilian), 125 (49.4%) were allocated a geographic

distribution score of 6, signifying that these creatures

are known only from the vicinity of their respective type

localities; the remainder of the endemic species (128

[50.6%]) are more broadly distributed within the country

(Appendix 1).

Of the 378 Mexican amphibian species, 128 (33.9%)

are limited in ecological distribution to one formation

(Appendix 1). Therefore, we emphasize that close to one-

half of the country’s endemic amphibian species are not

known to occur outside of the vicinity of their type local-

ities. In addition, essentially one-third are not known to

occur outside of a single forest formation. This situation

imposes serious challenges in our attempt to conserve the

endemic component of the strikingly important Mexican

amphibian fauna.

Comparison of IUCN Categorizations and

EVS Values

Table 3. Comparison of Environmental Vulnerability Scores (EVS) and IUCN categorizations for Mexican amphibians. Shaded

area at the top encompasses low vulnerability category scores, and that at the bottom high vulnerability category scores.

IUCN categories

EVS

Critically

Endangered

Vulnerable

Near

Threatened

Least

Concern

Data

Deficient

Not

Evaluated

Totals

3

4

5

6

7

8

1

—

2

4

3

8

6

—

1

2

4

3

4

9

12

9

1

10

—

1

15

10

1

2

1

—

9

—

2

15

11

1

2

7

—

13

—

23

12

5

4

3

4

13

2

1

32

13

4

12

5

6

3

1

36

14

12

11

7

2

8

6

3

49

15

22

8

5

2

3

10

3

53

16

4

9

4

2

1

—

21

17

15

17

6

2

1

7

2

50

18

19

21

1

13

3

1

—

9

1

48

1

Totals

88

79

44

21

91

38

17

378

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Conservation reassessment of Mexican amphibians

Ixalotriton niger. The black jumping salamander is known only from the immediate vicinity of the type locality in northwestern

Chiapas. Its EVS has been calculated as 18, placing it in the upper portion of the high vulnerability category, and its IUCN status

as Critically Endangered. This individual came from the type locality and was used as part of the type series in the description of

the species by Wake and Johnson (1989). The genus Ixalotriton is endemic to Mexico, and contains one other species (I. parvus).

Photo by David B. Wake.

Pseudoeurycea longicauda. The endemic long-tailed false brook salamander is distributed in the Transverse Volcanic Axis of east-

ern Michoacan and adjacent areas in the state of Mexico. Its EVS has been determined as 17, placing it in the middle of the high

vulnerability category, and its IUCN status as Endangered. This individual came from Zitacuaro, Michoacan, near the border with

the state of Mexico. Photo by Ivan Trinidad Ahumada- Carrillo.

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Wilson et al.

We noted in Wilson et al. (2013: 18) that, “Since the

IUCN categorizations and EVS values both measure the

degree of environmental threat impinging on a given spe-

cies, a certain degree of correlation between the results,

using the two measures, is expected.” They further in-

dicated that Townsend and Wilson (2010) demonstrated

this to be the case with the Honduran herpetofauna. Wil-

son et al. (2013: 22) concluded, however, that, “the re-

sults of the EVS analysis are nearly the reverse of those

obtained from the IUCN categorizations.”

We compared the results of these two conservation

measures in Table 3, expecting that our results for the

Mexican amphibians would be more consistent with those

obtained for the Honduran herpetofauna (Townsend and

Wilson 2010) than those garnered for the Mexican rep-

tiles (Wilson et al. 2013).

1. Nature of the IUCN categorizations in

Table 3

Like Wilson et al. (2013), we used the “Not Evaluated”

category (IUCN 2010), since 17 species (4.5%) have

not been evaluated at the IUCN Red List website, and

38 (10.1%) were evaluated as “Data Deficient” (www.

iucnredlist.org; accessed 08 May 2013). Thus, the IUCN

conservation status of 55 (14.6%) of the total amphibian

species remained undetermined. A greater proportion of

the Mexican amphibians, however, were assessed based

on the IUCN categorizations (323 species [85.4%]) than

the Mexican reptiles (Wilson et al. 2013).

2. Pattern of mean EVS vs. IUCN

categorizations

In order to more precisely determine the relationship be-

tween the IUCN categorizations and the EVS, we cal-

culated the mean EVS for each of the IUCN columns

in Table 3, including for the NE species and the total

species. The results are as follows: CR (88 spp.) = 15.5

(range 7-19); EN (79 spp.) = 15.1 (9-18); VU (44 spp.)

= 13.8 (8-18); NT (21 spp.) = 13.3 (8-18); LC (91 spp.)

= 10.0 (3-17); DD (38 spp.) = 15.6 (12-18); NE (17 spp.)

= 12.6 (6-18); and total (378 spp.) = 13.7 (3-19). The

results of these data show that the mean EVS decreases

steadily from the CR category (15.5) through the EN

(15.1), VU (13.8), and NT (13.3) categories to the LC

category (10.0). This pattern of decreasing values was

expected. In addition, the mean value for the DD species

(15.6) is closest to that for the CR species. As we stated

with regard to Mexican reptiles (Wilson et al. 2013: 22),

“this indicates what we generally have suspected about

the DD category, i.e., that the species placed in this cat-

egory likely will fall into the EN or CR categories when

(and if) their conservation status is better understood.

Placing species in this category is of little benefit to de-

termining their conservation status, however, since once

sequestered with this designation their significance tends

to be downplayed.” Wilson et al. (2013) demonstrated

that this problem was more significant with Mexican

reptiles, given that 118 species were evaluated as DD,

which provided the impetus to work on the 38 amphibian

Table 4. Comparison of Environmental Vulnerability Scores for Mexican amphibian and reptile species, arranged by major groups. Shaded area to the

left encompasses low vulnerability scores, and to the right high vulnerability scores.

Number of Environmental Vulnerability Scores

major groups

species

3

4

5

6

7

8

9

10

11

12

13

14

15

16

17

18

19

20

Anurans

237

4

3

4

9

12

14

13

20

25

29

36

30

8

14

12

1

—

Percentages

—

1.7

1.3

1.7

3.8

5.1

5.9

5.4

8.4

10.5

12.2

15.2

12.7

3.4

5.9

5.1

0.4

—

Salamanders

139

—

1

2

6

7

13

23

13

36

—

Percentages

—

0.7

1.4

4.3

5.0

9.4

16.6

9.4

25.9

—

Caecilians

2

1

Percentages

50.0

Amphibian Totals

378

4

3

4

9

12

15

23

32

36

49

53

21

50

48

1

—

Percentages

—

1.0

0.8

1.0

2.4

3.2

4.0

6.1

8.5

9.5

13.0

14.0

5.5

13.2

12.7

0.3

—

Crocodilians

3

1

—

1

—

Percentages

—

33.3

—

33.3

—

Turtles

42

—

1

—

3

1

3

8

6

4

3

5

6

1

Percentages

—

2.4

—

7.1

2.4

7.1

19.0

14.3

9.5

7.1

11.9

14.3

2.4

Lizards

409

—

1

3

6

11

12

15

26

39

49

54

67

77

37

10

2

—

Percentages

—

0.2

0.7

1.5

2.7

2.9

3.7

7.1

9.5

12.0

13.2

16.4

18.8

9.0

2.4

0.5

—

Snakes

382

1

7

10

9

19

17

30

25

31

46

52

50

44

24

9

7

—

Percentages

—

0.3

1.8

2.6

2.4

5.0

4.5

7.9

6.5

8.1

12.0

13.6

13.1

11.5

6.3

2.4

1.8

—

Reptile Totals

836

1

8

13

15

31

30

46

53

71

99

115

123

126

64

24

15

1

Percentages

—

0.1

1.0

1.6

1.8

3.7

3.6

5.5

6.3

8.5

11.8

13.8

14.7

15.1

7.8

2.9

1.8

0.1

August 2013 | Volume 7 | Number 1 | e69

Amphib. Reptile Conserv. | http://amphibian-reptile-conservation.org 111

Conservation reassessment of Mexican amphibians

Dermophis oaxacae. The endemic Oaxacan caecilian is distributed in Colima, Jalisco, Michoacan, Guerrero, Oaxaca, and Chiapas.

Its EVS has been calculated as 12, placing it in the middle portion of the medium vulnerability category, and its IUCN status as Data

Deficient. This individual was found on the road at Ixtlahuacan, Colima. Photo by Jacobo Reyes-Velasco.

species assessed as DD with those occupying the threat

categories (CR, EN, and VU) to arrive at a total of 249

species (65.9% of the total amphibian fauna). The EVS

range for these DD species (12-18) falls within that for

the threat species as a whole (7-19) and the mean for all

the four categories becomes 15.1, the same as that for the

EN species alone. So, if the DD species can be consid-

ered “threat species in disguise,” then close to two-thirds

of the Mexican amphibian species would be considered

under the threat of extinction.

The EVS for the 17 Mexican amphibian species that

have not been evaluated by the IUCN range from 6 to 1 8

(mean = 12.6). These species are of significant conserva-

tion interest, inasmuch as the EVS of nine of them falls

into the range of high vulnerability.

Based on the pattern of relationships between the LC

species and their corresponding EVS, this IUCN cate-

gory apparently has become a “dumping ground” for a

sizable number of Mexican amphibians (9 1 ; 24. 1 % of the

amphibian fauna) and like Wilson et al. (2013: 22) con-

cluded for Mexican reptiles, we concur that “A more dis-

cerning look at both the LC and NE species might dem-

onstrate that many should be partitioned into other IUCN

categories, rather than the LC.” The range of EVS values

for this category (3-17) is almost as broad as the range

of EVS (3-19) for amphibians as a whole; 37 (40.7%)

of these 91 species are relegated to the low vulnerabil-

ity range (3-9), 41 (45.0%) to the medium vulnerability

range, and 13 (14.3%) to the high vulnerability range.

Again, these results indicate that the LC category likely

has been used rather indiscriminately and that the EVS

algorithm provides a more useful conservation measure

than the IUCN system of categories.

Comparison of EVS Values for Mexican

Amphibians and Reptiles

One of our major reasons for writing this paper was to

determine the EVS values for Mexican amphibians, so

they could be compared to those calculated for Mexican

reptiles in Wilson et al. (2013). Thus, we summarized

the data in Table 2, and reduced them to the major group

level in Table 4. We also reduced the data in Wilson et al.

(2013: table 2) and placed them in our Table 4.

The data in this table indicate that the range of EVS

values are comparable for amphibians (3-19) and rep-

tiles (3-20). The EVS for the number of amphibian spe-

cies essentially increases until a score of 15 is reached

(53 species), and at 16 drops considerably (21 species)

only to spike back up at 17 and 18 (50 and 48 species,

respectively). The highest EVS value (19) was assigned

to a single species (the fringe-limbed hylid Ecnomiohyla

echinata ). For the reptiles, the numbers and percentages

also increase, with the peak (126 [15.1%]) reached at an

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Amphib. Reptile Conserv. | http://amphibian-reptile-conservation.org 112

Wilson et al.

EVS of 16, and decreasing rapidly thereafter. As with

amphibians, only a single species (the soft-shelled turtle

Apalone atra ) was assigned the highest EVS (20).

When the EVS values are arranged into low, medium,

and high categories, the numbers and percentages of spe-

cies are as follows (amphibians, followed by reptiles):

low = 50 (13.2%), 99 (11.8%); medium = 106 (28.0%),

269, (32.2%); and high = 222 (58.8%), 468, (56.0%).

The percentages for these two groups are comparable and

arranged in the same order. The greatest concern is that

in both amphibians and reptiles more than one-half of the

species fall into the upper portion of the high vulnerabil-

ity category, indicating that the Mexican herpetofauna is

seriously imperiled.

Of the major groups of amphibians and reptiles, Mex-

ican salamanders were judged the most imperiled. Of the

139 species known from the country, 121 (87.1%) were

assessed in the high vulnerability category. The compa-

rable figure for anurans is 101 (42.6%), less than one-

half of that for salamanders. Among the reptiles, lizards

were judged more threatened than snakes. Of the lizards,

247 (60.4%) fall within the high vulnerability category;

the comparable figures for snakes are 186 and 48.7%.

Turtles, although fewer in numbers, are more threatened

than other reptiles, with 33 species (78.6%) in the high

vulnerability category.

In the final analysis, although amphibians are ac-

knowledged widely as threatened on a global basis, a fair

accounting of the worldwide conservation status of most

reptiles remains unavailable. Our use of the EVS mea-

sure for Mexican amphibians and reptiles demonstrates

that both groups are in grave peril, and we expect that

this situation will worsen exponentially in the coming

decades.

Discussion

Global amphibian population decline has occupied the

attention of herpetologists since the late 1980s (Gas-

con et al. 2007). In the years that followed, the Global

Amphibian Assessment (GAA) was undertaken (Stuart

et al. 2004), which uncovered the startling conclusions

discussed in the Introduction. As noted in the foreword

to Gascon et al. (2007: 2), “the first GAA documented

the breadth of amphibian losses worldwide and made it

clear that business as usual — the customary conserva-

tion approaches and practices — were not working.” As

a result, an Amphibian Conservation Summit was con-

vened in September 2005, which resulted in a putatively

comprehensive Amphibian Conservation Action Plan

(ACAP; Gascon et al. 2007). The ACAP declaration pro-

posed (p. 59) that, “Four kinds of intervention are needed

to conserve amphibians, all of which need to be started

immediately:

1 . Expanded understanding of the causes of declines

and extinctions

Amphib. Reptile Conserv. | http://amphibian-reptile-conservation.org 113

2. Ongoing documentation of amphibian diversity,

and how it is changing

3. Development and implementation of long-term

conservation programmes

4. Emergency responses to immediate crises.”

We maintain that the ACAP does an admirable job of ex-

amining many of the issues directly related to amphibian

decline, but this examination essentially stops after con-

sidering the proximate symptoms of the problem. None-

theless, as noted by Wilson and Townsend (2010: 774),

“problems created by humans, i.e., overpopulation and

its sequelae, are not solved by treating only their symp-

toms, e.g., organismic endangerment.” Consequently,

trying to deal with a symptom of overpopulation and

resource overuse and abuse, such as amphibian decline,

will create only limited short-term responses, instead of

lasting solutions to the fundamental problems tied to the

impact of humans. Thus, ultimately, amphibian decline

will not be successfully addressed.

The fundamental problem is that humans have not

created a sustainable existence for themselves. Under-

standing why not is simple through examination of the

principles of sustainability elaborated by Miller and

Spoolman (2012: 6), as follows:

• “Nature has sustained itself for billions of years by

relying on solar energy, biodiversity, and nutrient cy-

cling.

• Our lives and economies depend on energy from

the sun and on natural resources and natural services

0 natural capital ) provided by the earth.

• As our ecological footprints grow, we are depleting

and degrading more of the earth’s natural capital.

• Major causes of environmental problems are popula-

tion growth, wasteful and unsustainable resource use,

poverty, and not including the harmful environmental

costs of resource use in the market prices of goods

and services.

• Our environmental worldview plays a key role in

determining whether we live unsustainably or more

sustainably.

• Living sustainably means living off the earth’s natu-

ral income without depleting or degrading the natural

capital that supplies it.”

Living unsustainably is a consequence of unregulated

human population growth that generates the overuse and

abuse of renewable and non-renewable resources, and

dependence on a cost-accounting system that ignores

factoring in clean up expenses in determining how goods

and services are priced. Life-sustaining resources are not

distributed equitably among people, but along a scale

ranging from very high to very low. Poverty is the conse-

quence of existing at the low end of the scale, where peo-

ple are unable to meet their basic needs for adequate food

and water, clothing, or shelter (Raven and Berg 2004).

August 2013 | Volume 7 | Number 1 | e69

Conservation reassessment of Mexican amphibians

Environmental scientists use the concept of ecological

footprint to express “the average amount of land and

ocean needed to supply an individual with food, energy,

water, housing, transportation, and waste disposal” (Ra-

ven and Berg 2004: G-5). The global ecological footprint

has increased over the years to the point that the Global

Footprint Network calculated it would take “1.5 years to

generate the renewable resources used in 2008” (WWF

Fiving Planet Report 2012: 40). “Humanity’s annual de-

mand on the natural world has exceeded what the Earth

can renew in a year since the 1970s,” which has created

a so-called “ecological overshoot” (WWF Fiving Planet

Report 2012: 40). Thus, Earth’s capital (its biocapacity)

is being depleted on a continually growing basis, and the

planet is becoming less capable of supporting life in gen-

eral, and human life in particular. Estimates indicate that

by the year 2050, under a “business as usual” scenario, it

would require an equivalent of 2.9 planets to support the

amount of humanity expected to exist at that time (WWF

Fiving Planet Report 2012: 101).

The World Wildlife Fund promulgated its “One Planet

perspective,” which “explicitly proposes to manage, gov-

ern and share natural capital within the Earth’s ecologi-

cal boundaries. In addition to safeguarding and restoring

this natural capital, WWF seeks better choices along the

entire system of production and consumption, supported

by redirected financial flows and more equitable resource

governance. All of this, and more, is required to decou-

ple human development from unsustainable consump-

tion (moving away from material and energy-intensive

commodities), to avoid greenhouse gas emissions, to

maintain ecosystem integrity, and to promote pro-poor

growth and development” (WWF Fiving Planet Report

2012: 106).

Only within this context will the provisions of ACAP

have the desired effects, i.e., to preserve the portion of

natural capital represented by amphibians. Thus, in writ-

ing about the conservation status of the amphibians of

Mexico, we are constructing our conclusions and recom-

mendations in light of these global imperatives.

Conclusions and Recommendations

We structured our conclusions and recommendations af-

ter those of Wilson and Townsend (2010) for the entire

Mesoamerican herpetofauna, refining them specifically

for the Mexican amphibian fauna, as follows:

1. Given that Mexico contains the highest level of

amphibian diversity and endemicity in the Me-

soamerican biodiversity hotspot, our most funda-

mental recommendation is that protection of this

aspect of the Mexican patrimony should be made

a major component of the management strategy of

the Secretarra de Medio Ambiente y Recursos Na-

turales (SEMARNAT). In turn, that strategy needs

to be incorporated into an overall plan for a sus-

Amphib. Reptile Conserv. | http://amphibian-reptile-conservation.org 114

tainable future for Mexico, of which the most criti-

cal component is to “explicitly integrate population

dynamics (size, growth rate, composition, location

and migration) and per capita consumption trends

into national planning policies to support a better

balance between population and available resourc-

es” (WWF Fiving Planet Report 2012: 121).

2. All organisms have intrinsic and extrinsic value,

especially as components of healthily functioning

ecosystems, but we believe that although conserva-

tion efforts should extend to all species in a given

area, most interest should be focused on species

with a limited distribution (i.e., endemic species).

The rationale for this position is that funds to sup-

port conservation initiatives have remained scarce,

although this situation will have to change in the

near future. The principal regions of Mexican am-

phibian endemism are the Sierra Madre Oriental,

the Sierra Madre del Sur, and the Mesa Central,

in the order listed. Unfortunately, about 39% of

Mexico’s population occupies the Mesa Central

(Flores- Villela et al. 2010). Inasmuch as this con-

centrated population will continue to grow into the

foreseeable future, not only as a consequence of

the rate of natural increase (1.4% in Mexico), but

also because of the increase in the percentage of

the population attracted to the large cities of the

Mesa Central (Guadalajara, Feon, Mexico, Mo-

relia, Salamanca, and others; Flores- Villela et al.

2010), it is critically important to make the am-

phibian fauna of the Mesa Central a fundamental

component of the national plan for biodiversity

protection by SEMARNAT.

3. Oscar Flores- Villela and his colleagues produced

highly significant conservation analyses (Flores-

Villela 1993; Flores- Villela and Gerez 1994;

Ochoa-Ochoa and Flores- Villela 2006; Flores- Vil-

lela et al. 2010) that have documented the centers

of diversity and endemism of the Mexican herpe-

tofauna. Given the large disparity between these

centers and the placement of protected areas in

the country, we can only echo the conclusions of

Flores- Villela et al. (2010: 313) that, “Given the

great importance of the herpetofauna of the Central

Highlands of Mexico, both in terms of its diversity

and endemicity, appropriate steps need to be taken

quickly to establish protected areas around the cen-

ter of herpetofaunal endemism in the Sierra Madre

del Sur, and to reassess the ability of the protected

areas already established in the Mesa Central to

encompass their centers of endemism.” A simi-

lar recommendation can be made with respect to

the other centers, e.g., the Sierra Madre Oriental,

which has been even more ignored than areas in the

Central Highlands (Favrn et al. 2010).

August 2013 | Volume 7 | Number 1 | e69

Wilson et al.

4. Finding ways to use biodiversity sustainably must

become a fundamental goal for all humanity. The

steps necessary to achieve this end are not difficult

to envision; the problem lies in marshaling the par-

adigm shift necessary to make the transition. The

major steps involve: (a) creating a reality-based

educational system that will prepare people for the

world as it is and will come to be, instead of the

way people wish it were; (b) integrating education-

al reform into a broad-based plan for governmen-

tal and economic reform founded on principles of

equality, shared responsibility, and commitment to

a sustainable future for humanity and the natural

world; (c) using governmental and economic re-

form to design a global society structured to exist

within the limits of nature; and (d) basing a soci-

ety on the notion that everyone must work toward

this end. Within such overarching goals, the task

of learning the best way to catalogue, protect, and

make sustainable use of the world’s organisms is a

huge undertaking. New molecular-based technol-

ogy, however, is allowing for a better understand-

ing of biological diversity, which is much greater

than we previously envisioned. Because of the ac-

celerating rate at which we are losing biological di-

versity, biologists are faced with helping humanity

adopt a worldview in which all species matter, and

that the sustainability of humans will depend on

reforming our society based on the framework for

survival tested by the process of natural selection

over the last 3.5 billion years life has occupied our

planet (Beattie and Ehrlich 2004).

5. In 2012, the United Nations Secretary-General’s

High-level Panel on Global Sustainability pro-

duced a seminal report entitled “Resilient People,

Resilient Planet: A Future Worth Choosing.” In a

vision statement (p. 13), the panel introduced the

concept of “tipping points,” as follows: “The cur-

rent global development model is unsustainable.

We can no longer assume that our collective ac-

tions will not trigger tipping points as environmen-

tal thresholds are breached, risking irreversible

damage to both ecosystems and human communi-

ties. At the same time, such thresholds should not

be used to impose arbitrary growth ceilings on de-

veloping countries seeking to lift their people out

of poverty. Indeed, if we fail to resolve the sus-

tainable development dilemma, we run the risk of

condemning up to 3 billion members of our human

family to a life of endemic poverty. Neither of

these outcomes is acceptable, and we must find a

new way forward.” The panel also pointed out (p.

14) that “it is time for bold global efforts, includ-

ing launching a major global scientific initiative,

to strengthen the interface between science and

policy. We must define, through science, what sci-

entists refer to as ‘planetary boundaries,’ ‘environ-

mental thresholds,’ and ‘tipping points.” On p. 23,

they emphasize that, “awareness is growing of the

potential for passing ‘tipping points’ beyond which

environmental change accelerates, has the poten-

tial to become self-perpetuating, and may be dif-

ficult or even impossible to reverse.” Environmen-

tal scientists have warned of this eventuality for

decades; most of the world’s people just have not

listened. The Stockholm Resilience Centre (www.

stockholmresilience.org), however, has exposed

a number of “planetary boundaries,” defined as

certain thresholds or tipping points beyond which

there is the “risk of irreversible and abrupt environ-

mental change” (Box 2 on p. 24 of the UN panel re-

port). The Stockholm Resilience Centre sponsored

a group of scientists (Rockstrom et al. 2009) that

identified nine planetary boundaries, including:

“climate change, rate of biodiversity loss, biogeo-

chemical flows (both nitrogen and phosphorus),

stratospheric ozone depletion, ocean acidification,

global freshwater use, change in land use, atmo-

spheric aerosol loading and chemical pollution.”

The scientists estimated that “human activity ap-

pears to have already transgressed the [planetary]

boundaries associated with climate change, rate of

biodiversity loss and changes to the global nitrogen

cycle.” Furthermore, “humanity may soon be ap-

proaching the boundaries for interference with the

global phosphorous cycle, global freshwater use,

ocean acidification and global change in land use.”

Finally, they concluded that, “the boundaries are

strongly interlinked, so that crossing one may shift

others and even cause them to be overstepped.”

As a consequence of these realities, governments

across the globe are faced with the choice of con-

tinuing to do “business as usual,” ultimately spill-

ing over all the planetary boundaries and ending up

in a world in which all of our options have been ex-

hausted except for the last one... the option to fail,

or to pull together to develop a human existence

lying within planetary boundaries in order to define

a “safe operating space for humanity.” Our chances

to avoid the one and succeed with the other will

depend on how well humanity is able to embrace

new ways of thinking about our problems and en-

list the help of groups of people who traditionally

have been marginalized — especially women and

the young. These words apply to Mexico, as they

do to all other countries in the world.

The three authors of this work are herpetologists who

specialize in research on amphibians and reptiles in Me-

soamerica. This paper focuses on the conservation status

of the amphibians of Mexico, and follows a si mil ar effort

on the reptiles (Wilson et al. 2013). We demonstrated by

using both the IUCN categorizations and EVS measure

August 2013 | Volume 7 | Number 1 | e69

Amphib. Reptile Conserv. | http://amphibian-reptile-conservation.org 115

Conservation reassessment of Mexican amphibians

that the Mexican amphibian fauna is one of the most se-

riously threatened of any existing in the world. All indi-

cations suggest that humans have transgressed the plan-

etary boundaries associated with biodiversity loss, and

there is no time to lose to reverse this dismantling trend

or our descendants will be left to conclude that our gen-

eration condemned them to an environmentally impover-

ished world by our inaction. In the final analysis, life on

Earth has survived five prior mass extinction events; hu-

manity’s job now is to survive the one of its own making.

Acknowledgments. — We are thankful to the follow-

ing individuals for improving the quality of this contribu-

tion: Javier Alvarado-Dfaz, Irene Goyenechea, and Louis

W. Porras. We are most grateful to Louis, who applied

his amazing editing skills to the job of making our work

better than what we initially produced.

Literature Cited

Acevedo M, Wilson LD, Cano EB, Vasquez-Almazan C.

2010. Diversity and conservation status of the Gua-

temalan herpetofauna. Pp. 406-435 In: Conservation

of Mesoamerican Amphibians and Reptiles. Editors,

Wilson LD, Townsend JH, Johnson JD. Eagle Moun-

tain Publishing, LC, Eagle Mountain, Utah, USA.

Beattie A, Ehrlich PR. 2004. Wild Solutions: How Bio-

diversity is Money in the Bank. Yale University Press,

New Haven, Connecticut, USA.

Bright C. 2000. Anticipating environmental “surprise.”

Pp. 22-38 In: State of the World 2000. Editors, Brown

LR, Flavin C. W. W. Norton and Company, New York,

New York, USA.

Campbell JA, Blancas-Hemandez JC, Smith EN. 2009.

A new species of stream-breeding treefrog of the ge-

nus Charadrahyla (Hylidae) from the Sierra Madre

del Sur of Guerrero, Mexico. Copeia 2009: 287-295.

Campbell NA, Reese JB, Taylor MR, Simon EJ. 2008.

Biology: Concepts and Connections (8 th edition).

Pearson Benjamin Cummings, New York, New York,

USA.

Collins JP, Crump ML. 2009. Extinction in our Times:

Global Amphibian Decline. Oxford University Press,

New York, New York, USA.

Flores-Villela O. 1993. Herpetofauna of Mexico: distri-

bution and endemism. Pp. 253-280 In: Biological Di-

versity of Mexico: Origins and Distributions. Editors,

Ramamoorthy TP, Bye R, Lot A, Fa J. Oxford Univer-

sity Press, New York, New York, USA.

Flores-Villela O, Canseco-Marquez L, Ochoa-Ochoa

LM. 2010. Geographic distribution and conservation

of the Mexican Central Highlands herpetofauna. Pp.

303-321 In: Conservation of Mesoamerican Amphib-

ians and Reptiles. Editors, Wilson LD, Townsend JH,

Johnson JD. Eagle Mountain Publishing, LC, Eagle

Amphib. Reptile Conserv. | http://amphibian-reptile-conservation.org 116

Mountain, Utah, USA.

Flores-Villela O, Gerez P. 1994. Biodiver sidad y Conser-

vacion en Mexico: Vertebrados, Vegetacion y Uso de

Suelo (2 nd edition). CONABIO/UNAM, Mexico, DF,

Mexico.

Frost DR. 2013. Amphibian Species of the World: An On-

line Reference. Versions 5.6 (9 January 2013). Elec-

tronic Database available at www. research.amnh.org/

herpetology/amphibia/index.html [Accessed: 15 June

2013]. American Museum of Natural History, New

York, New York, USA.

Gascon C, Collins JP, Moore RD, Church DR, McKay

JE, Mendelson III JR (Editors). 2007. Amphibian

Conservation Action Plan. IUCN/SSC Amphibian

Specialist Group. Gland, Switzerland and Cambridge,

United Kingdom.

Hedges SB, Duellman WE, Heinicke MP. 2008. New

World direct-developing frogs (Anura: Terrarana):

molecular phylogeny, classification, biogeography,

and conservation. Zootaxa 1737: 1-182.

Jaramillo C, Wilson LD, Ibanez R, Jaramillo F. 2010.

The herpetofauna of Panama: distribution and conser-

vation status. Pp. 604-673 In: Conservation of Meso-

american Amphibians and Reptiles. Editors, Wilson

LD, Townsend JH, Johnson JD. Eagle Mountain Pub-

lishing, LC, Eagle Mountain, Utah, USA.

Kohler G. 2011. Amphibians of Central America. Herpe-

ton, Verlag Elke Kohler, Offenbach, Germany.

Lavilla EO, Langone JA, Padial JM, de Sa RO. 2010.

The identity of the crackling, luminescent frog of Su-

riname (Rana typhonia Linnaeus, 1758) (Amphibia,

Anura). Zootaxa 2671: 17-30.

Lavfn-Murcio PA, Lazcano D. 2010. Geographic distri-

bution and conservation of the herpetofauna of north-

ern Mexico. Pp. 274-301 In: Conservation of Meso-

american Amphibians and Reptiles. Editors, Wilson

LD, Townsend JH, Johnson JD. Eagle Mountain Pub-

lishing, LC, Eagle Mountain, Utah, USA.

Mendelson III JR, Mulcahy DG, Snell S, Acevedo ME,

Campbell JA. 2012. A new golden toad (Bufonidae:

Incilius ) from northwestern Guatemala and Chiapas,

Mexico. Journal of Herpetology 46: 473-479.

Miller GT, Spoolman S. 2012. Environmental Science

(14 th edition). Brooks Cole, Belmont, California,

USA.

Mora C, Tittensor DP, Adi S, Simpson AGB, Worm B.

2011. How many species are there on Earth and in the

ocean? PLoS Biology 9(8): el001127. doi:10.1371/

j ournal.pbio. 1001127

Ochoa-Ochoa LM, Flores-Villela O. 2006. Areas de Di-

versidad y Endemismo de la Herpetofauna Mexicana.

UNAM-CONABIO, Mexico, DF, Mexico.

Parra-Olea G, Papenfuss TJ, Wake DB. 2001. New spe-

cies of lungless salamanders of the genus Pseudoeury-

cea (Amphibia: Caudata: Plethodontidae) from Vera-

cruz, Mexico. Scientific Papers of the Natural History

August 2013 | Volume 7 | Number 1 | e69

Wilson et al.

Museum, University of Kansas 20: 1-9.

Parra-Olea G, Rovito SM, Marquez-Valdelamar L, Cruz

G, Murrieta-Galindo R, Wake DB. 2010. A new spe-

cies of Pseudoeurycea from the cloud forest in Vera-

cruz, Mexico. Zootaxa 2725: 57-68.

/

Raffaelli J. 2007. Les Urodeles du Monde. Penclen Edi-

tion, Plumelec, France.

Raven PH, Berg LR. 2004. Environment (4 th edition).

John Wiley & Sons, Inc. Hoboken, New Jersey, USA.

Rockstrom J, Steffen W, Noone K, Persson A, Chapin

FS III, Fambin E, Fenton TM, Scheffer M, Folke C,

Schellnhuber HJ, Nykvist B, de Wit CA, Hughes T,

van der Feeuw S, Rodhe H, Sorlin S, Snyder PK,

Costanza R, Svedin U, Falkenmark M, Karlberg F,

Corell RW, Fabry VJ, Hansen J, Walker B, Fiverman

D, Richardson K, Crutzen P, Foley J. 2009. Planetary

boundaries: exploring the safe operating space for hu-

manity. Ecology and Society 14(2): 1-32.

Rovito SM, Parra-Olea G, Fee D, Wake DB. 2012. Anew

species of Bolitoglossa (Amphibia, Caudata) from

the Sierra de Juarez, Oaxaca, Mexico. ZooKeys 185:

55-71.

Santo s-Barrera G, Flores- Villela O. 2011. Anew species

of toad of the genus Incilius from the Sierra Madre

Occidental of Chihuahua, Mexico. Journal of Herpe-

tology AS: 211-215.

Smith SA, Arif S, Nieto-Montes de Oca A, Wiens JJ.

2007. A phylogenetic hot spot for evolutionary nov-

elty in Middle American treefrogs. Evolution 61:

2075-2085.

Streicher JW, Cox CF, Campbell JA, Smith EN, de Sa

RO. 2012. Rapid range expansion in the Great Plains

narrow-mouthed toad ( Gastrophryne olivacea) and a

revised taxonomy for North American microhylids.

Molecular Phylogenetics and Evolution 64: 645-653.

Stuart SN, Chanson JS, Cox NA, Young BE, Rodrigues

ASF, Fischman DF, Waller RW. 2004. Status and

trends of amphibian declines and extinctions world-

wide. Science 306(5702): 1783-1786.

Stuart SN, Hoffman M, Chanson JS, Cox NA, Berridge

RJ, Ramani P, Young BE. 2008. Threatened Amphib-

ians of the World. Fynx Ediciones, Barcelona, Spain.

Stuart SN, Chanson JS, Cox NA, Young BE. 2010. The

global decline of amphibians: current trends and fu-

ture prospects. Pp. 2-15 In: Conservation of Meso-

american Amphibians and Reptiles. Editors, Wilson

ED, Townsend JH, Johnson JD. Eagle Mountain Pub-

lishing, EC, Eagle Mountain, Utah, USA.

Townsend JH, Wilson ED. 2010. Conservation of the

Honduran herpetofauna: Issues and imperatives. Pp.

460-435. In: Conservation of Mesoamerican Amphib-

ians and Reptiles. Editors, Wilson ED, Townsend JH,

Johnson JD. Eagle Mountain Publishing, LC, Eagle

Mountain, Utah, USA.

United Nations Secretary-General’s High-level Panel on

Global Sustainability. 2012. Resilient People, Resil-

ient Planet: A Future Worth Choosing. United Na-

tions, New York, New York, USA.

Vitt LJ, Caldwell JP. 2009. Herpetology (3 rd edition).

Academic Press, Burlington, Maine, USA.

Wake DB. 2012. Taxonomy of salamanders of the family

Plethodontidae (Amphibia: Caudata). Zootaxa 3484:

75-82.

Wake DB, Johnson JD. 1989. Anew genus and species of

plethodontid salamander from Chiapas, Mexico. Con-

tributions in Science Natural History Museum of Los

Angeles County 411: 1-10.

Wilson LD, Johnson JD. 2010. Distributional patterns

of the herpetofauna of Mesoamerica, a biodiversity

hotspot. Pp. 30-235 In: Conservation of Mesoameri-

can Amphibians and Reptiles. Editors, Wilson LD,

Townsend JH, Johnson JD. Eagle Mountain Publish-

ing, LC, Eagle Mountain, Utah.

Wilson LD, Mata-Silva V, Johnson JD. 2013. A conser-

vation reassessment of the reptiles of Mexico based

on the EVS measure. Amphibian & Reptile Conserva-

tion 7: 1-47.

Wilson LD, McCranie JR. 2004. The conservation status

of the herpetofauna of Honduras. Amphibian & Rep-

tile Conservation 3: 6-33.

Wilson LD, Townsend JH. 2010. The herpetofauna of

Mesoamerica: Biodiversity significance, conservation

status, and future challenges. Pp. 76-812 In: Conser-

vation of Mesoamerican Amphibians and Reptiles.

Editors, Wilson LD, Townsend JH, Johnson JD. Eagle

Mountain Publishing, LC, Eagle Mountain, Utah,

USA.

Wilson LD, Townsend JH, Johnson JD. 2010. Conserva-

tion of Mesoamerican Amphibians and Reptiles. Ea-

gle Mountain Publishing, LC, Eagle Mountain, Utah,

USA.

World Wildlife Fund. 2012. Living Planet Report 2012.

WWF International, Gland, Switzerland.

Received: 05 March 2013

Accepted: 26 April 2013

Published: 02 August 2013

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Conservation reassessment of Mexican amphibians

Larry David Wilson is a herpetologist with lengthy experience in Mesoamerica, totaling six collective years

(combined over the past 47). Larry is the senior editor of the recently published Conservation of Mesoameri-

can Amphibians and Reptiles and a co-author of seven of its chapters. He retired after 35 years of service as

Professor of Biology at Miami-Dade College in Miami, Florida. Larry is the author or co-author of more than

290 peer-reviewed papers and books on herpetology, including the 2004 Amphibian & Reptile Conserva-

tion paper entitled “The conservation status of the herpetofauna of Honduras.” His other books include The

Snakes of Honduras, Middle American Herpetology, The Amphibians of Honduras, Amphibians & Reptiles

of the Bay Islands and Cayos Cochinos, Honduras, The Amphibians and Reptiles of the Honduran Mosquitia,

and Guide to the Amphibians & Reptiles of Cusuco National Park, Honduras. He also served as the Snake

Section Editor for the Catalogue of American Amphibians and Reptiles for 33 years. Over his career, Larry

has authored or co-authored the descriptions of 69 currently recognized herpetofaunal species and six spe-

cies have been named in his honor, including the anuran Craugastor lauraster and the snakes Cerrophidion

wilsoni, Myriopholis wilsoni, and Oxybelis wilsoni.

Jerry D. Johnson is Professor of Biological Sciences at The University of Texas at El Paso, and has exten-

sive experience studying the herpetofauna of Mesoamerica. He is the Director of the 40,000 acre “Indio

Mountains Research Station,” was a co-editor on the recently published Conservation of Mesoamerican

Amphibians and Reptiles, and is Mesoamerica/Caribbean editor for the Geographic Distribution section of

Herpetological Review. Johnson has authored or co-authored over 80 peer-reviewed papers, including two

2010 articles, “Geographic distribution and conservation of the herpetofauna of southeastern Mexico” and

“Distributional patterns of the herpetofauna of Mesoamerica, a biodiversity hotspot.”

Vicente Mata-Silva is a herpetologist interested in ecology, conservation, and the monitoring of amphibians and

reptiles in Mexico and the southwestern United States. His bachelor’s thesis compared herpetofaunal richness

in Puebla, Mexico, in habitats with different degrees of human related disturbance. Vicente’s master’s thesis

focused primarily on the diet of two syntopic whiptail species of lizards, one unisexual and the other bisexual,

in the Trans-Pecos region of the Chihuahuan Desert. Currently, he is a postdoctoral research fellow at the

University of Texas at El Paso, where his work focuses on rattlesnake populations in their natural habitat. His

dissertation was on the ecology of the rock rattlesnake, Crotalus lepidus, in the northern Chihuahuan Desert.

To date, Vicente has authored or co-authored 34 peer-reviewed scientific publications.

August 2013 | Volume 7 | Number 1 | e69

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118

Wilson et al.

Appendix 1 . Comparison of the IUCN Ratings from the Red List Website (updated to 08 May 2013) and Environmental

Vulnerability Scores for 378 Mexican Amphibians. See text for explanations of the IUCN and EVS rating systems. * =

species endemic to Mexico.

Species

IUCN

rating

Environmental Vulnerability Score

Geographic

Distribution

Ecological

Distribution

Reproductive

Mode

Total Score

Order Anura (237 species)

Family Bufonidae (35 species)

Anaxyrus boreus

NT

3

4

1

8

Anaxyrus californicus

EN

4

7

1

12

Anaxyrus cognatus

LC

3

5

1

9

Anaxyrus compactilis*

LC

5

8

1

14

Anaxyrus debilis

LC

1

5

1

7

Anaxyrus kelloggi*

LC

5

8

1

14

Anaxyrus mexicanus*

NT

5

7

1

13

Anaxyrus punctatus

LC

1

3

1

5

Anaxyrus retiformis

LC

4

7

1

12

Anaxyrus speciosus

LC

4

7

1

12

Anaxyrus woodhousii

LC

3

6

1

10

Incilius alvarius

LC

4

6

1

11

Incilius aurarius

NE

4

8

1

13

Incilius bocourti

LC

4

6

1

11

Incilius campbelli

NT

4

8

1

13

Incilius canaliferus

LC

4

3

1

8

Incilius cavifrons*

EN

5

7

1

13

Incilius coccifer

LC

3

5

1

9

Incilius cristatus*

CR

5

8

1

14

Incilius cycladen*

VU

5

8

1

14

Incilius gemmifer*

EN

6

8

1

15

Incilius luetkenii

LC

3

1

7

Incilius macrocristatus

VU

4

6

1

11

Incilius marmoreus*

LC

5

1

11

Incilius mazatlanensis*

LC

5

6

1

12

Incilius mccoyi*

NE

5

8

1

14

Incilius nebulifer

LC

1

4

1

6

Incilius occidental is*

LC

5

1

11

Incilius perplexus*

EN

5

1

11

Incilius pisinnus*

DD

6

8

1

15

Incilius spiculatus*

EN

5

7

1

13

Incilius tacanensis

EN

4

1

9

Incilius tutelarius

EN

4

5

1

10

Incilius valliceps

LC

3

2

1

6

Rhinella marina

LC

1

3

Family Centrolenidae (1 species)

Hyalinobatrachium fleischmanni

LC

3

4

3

10

Family Craugastoridae (39 species)

Craugastor alfredi

VU

2

5

4

11

Craugastor amniscola

DD

4

6

4

14

Craugastor augusti

LC

2

4

8

Craugastor batrachylus*

DD

6

8

4

18

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Conservation reassessment of Mexican amphibians

Craugastor berkenbuschii*

NT

5

4

14

Craugastor brocchi

VU

4

6

4

14

Craugastor decoratus*

VU

5

6

4

15

Craugastor galacticorhinis*

NE

6

8

4

15

Craugastor glaucus *

CR

6

8

4

18

Craugastor greggi

CR

4

7

4

15

Craugastor guerreroensis*

CR

6

8

4

18

Craugastor hobartsmithi*

EN

5

6

4

15

Craugastor laticeps

NT

4

12

Craugastor lineatus

CR

4

7

4

15

Craugastor loki

LC

2

4

10

Craugastor matudai

VU

4

7

4

15

Craugastor megalotympanum*

CR

6

8

4

18

Craugastor mexicanus*

LC

5

7

4

16

Craugastor montan us*

EN

6

8

4

18

Craugastor occidental is*

DD

5

4

13

Craugastor omiltemanus*

EN

5

7

4

16

Craugastor palenque

DD

4

7

4

15

Craugastor pelorus *

DD

5

6

4

15

Craugastor polymniae *

CR

6

8

4

18

Craugastor pozo*

CR

6

7

4

17

Craugastor pygmaeus

VU

2

3

4

9

Craugastor rhodopis*

VU

5

4

14

Craugastor rugulosus*

LC

5

4

13

Craugastor rupinius

LC

4

5

4

13

Craugastor saltator*

NE

5

6

4

15

Craugastor silvicola *

EN

6

8

4

18

Craugastor spatulatus*

EN

5

7

4

16

Craugastor stuarti

EN

4

7

4

15

Craugastor tarahumaraensis*

VU

5

8

4

17

Craugastor taylori*

DD

6

8

4

18

Craugastor uno*

EN

5

8

4

17

Craugastor vocal is*

LC

5

4

13

Craugastor vulcani*

EN

6

7

4

17

Craugastor yucatanensis *

NT

5

8

4

17

Family Eleutherodactylidae (23 species)

Eleutherodactylus albolabris*

NE

6

7

4

17

Eleutherodactylus angustidigitorum *

VU

5

8

4

17

Eleutherodactylus cystignathoides

LC

2

6

4

12

Eleutherodactylus dennisi*

EN

6

8

4

18

Eleutherodactylus dilatus*

EN

5

8

4

17

Eleutherodactylus grand is*

CR

6

8

4

18

Eleutherodactylus guttilatus

LC

2

5

4

11

Eleutherodactylus interorbital is *

DD

5

6

4

15

Eleutherodactylus leprus

VU

2

6

4

12

Eleutherodactylus longipes*

VU

5

6

4

15

Eleutherodactylus maurus*

DD

5

8

4

17

Eleutherodactylus modestus*

VU

5

7

4

16

Eleutherodactylus nitidus*

LC

5

3

4

12

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Wilson et al.

Eleutherodactylus nivicolimae *

VU

6

7

4

17

Eleutherodactylus pallidus*

DD

5

8

4

17

Eleutherodactylus pipilans

LC

2

5

4

11

Eleutherodactylus rubrimaculatus

VU

4

7

4

15

Eleutherodactylus rufescens*

CR

6

7

4

17

Eleutherodactylus saxatilis*

EN

5

8

4

17

Eleutherodactylus syristes*

EN

5

7

4

16

Eleutherodactylus teretistes*

DD

5

7

4

16

Eleutherodactylus verrucipes*

VU

5

7

4

16

Eleutherodactylus verruculatus*

DD

6

8

4

18

Family Hylidae (97 species)

Acris blanchardi

NE

3

8

1

12

Agalychnis callidryas

LC

3

5

3

11

Agalychnis dacnicolor*

LC

5

3

13

Agalychnis moreletii

CR

1

3

7

Anotheca spinosa

LC

3

6

5

14

Bromeliohyla bromeliacia

EN

4

7

5

16

Bromeliohyla dendroscarta*

CR

5

7

5

17

Charadrahyla altipotens*

CR

5

6

1

12

Charadrahyla chaneque*

EN

5

7

1

13

Charadrahyla nephila*

VU

5

7

1

13

Charadrahyla taeniopus*

VU

5

7

1

13

Charadrahyla tecuani*

NE

6

8

1

15

Charadrahyla trux*

CR

6

7

1

14

Dendropsophus ebraccatus

LC

3

6

3

10

Dendropsophus microcephalus

LC

3

1

7

Dendropsophus robertmertensi

LC

4

1

9

Dendropsophus sartori*

LC

5

8

1

14

Diaglena spatulata*

LC

5

7

1

13

Duellmanohyla chamulae*

EN

6

7

1

13

Duellmanohyla ignicolor*

EN

6

7

1

14

Duellmanohyla schmidtorum

VU

4

3

1

8

Ecnomiohyla echinata*

CR

6

8

5

19

Ecnomiohyla miotympanum*

NT

5

3

1

9

Ecnomiohyla valancifer*

CR

6

7

5

18

Exerodonta abdivita*

DD

6

8

1

15

Exerodonta bivocata*

DD

6

8

1

15

Exerodonta chimalapa*

EN

6

5

1

12

Exerodonta juanitae*

VU

5

8

1

14

Exerodonta melanomma*

VU

5

1

11

Exerodonta pinorum*

VU

5

7

1

13

Exerodonta smaragdina*

LC

5

6

1

12

Exerodonta sumichrasti*

LC

5

3

1

9

Exerodonta xera*

VU

5

8

1

14

Hyla arboricola*

DD

5

6

1

12

Hyla arenicolor

LC

2

4

1

7

Hyla euphorbiacea*

NT

5

7

1

13

Hyla eximia*

LC

5

4

1

10

Hyla plicata*

LC

5

1

11

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Conservation reassessment of Mexican amphibians

Hyla walkeri

VU

4

6

1

11

Hyla wrightorum

LC

2

6

1

9

Megastomatohyla mixe*

CR

6

8

1

15

Megastomatohyla mixomaculata*

EN

5

8

1

14

Megastomatohyla nubicola*

EN

5

8

1

14

Megastomatohyla pellita*

CR

6

7

1

14

Plectrohyla acanthodes

CR

4

7

1

12

Plectrohyla ameibothalame*

DD

6

8

1

15

Plectrohyla arborescandens*

EN

5

1

11

Plectrohyla avia

CR

4

8

1

13

Plectrohyla bistincta*

LC

5

3

1

9

Plectrohyla calthula*

CR

5

8

1

14

Plectrohyla calvicollina*

CR

6

7

1

14

Plectrohyla celata*

CR

6

7

1

14

Plectrohyla cembra*

CR

5

8

1

14

Plectrohyla charadricola*

EN

5

8

1

14

Plectrohyla chryses*

CR

6

7

1

14

Plectrohyla crassa*

CR

5

8

1

14

Plectrohyla cyanomma*

CR

5

8

1

14

Plectrohyla cyclada*

EN

5

8

1

14

Plectrohyla ephemera*

CR

6

8

1

15

Plectrohyla guatemalensis

CR

4

1

9

Plectrohyla hartwegi

CR

4

5

1

10

Plectrohyla hazelae*

CR

5

6

1

12

Plectrohyla ixil

CR

4

7

1

12

Plectrohyla labedactyla*

DD

6

8

1

15

Plectrohyla lacertosa*

EN

5

8

1

14

Plectrohyla matudai

VU

4

6

1

11

Plectrohyla miahuatlanensis*

DD

6

8

1

15

Plectrohyla mykter*

EN

5

7

1

13

Plectrohyla pachyderma*

CR

6

8

1

15

Plectrohyla pentheter*

EN

5

7

1

13

Plectrohyla psarosema*

CR

6

8

1

15

Plectrohyla pych nochi la*

CR

6

8

1

15

Plectrohyla robertsorum*

EN

5

7

1

13

Plectrohyla sabrina*

CR

5

8

1

14

Plectrohyla sagorum

EN

4

5

1

10

Plectrohyla siopela*

CR

6

8

1

15

Plectrohyla thorectes*

CR

5

7

1

13

Pseudacris cadaverina

LC

4

6

1

11

Pseudacris dark i

LC

3

8

1

12

Pseudacris hypochondriaca

NE

4

1

9

Ptychohyla acrochorda*

DD

6

7

1

14

Ptychohyla erythromma*

EN

5

7

1

13

Ptychohyla euthysanota

NT

4

3

1

8

Ptychohyla leonhardschultzei*

EN

5

6

1

12

Ptychohyla macrotympanum

CR

4

6

1

11

Ptychohyla zophodes*

DD

5

7

1

13

Scinax staufferi

LC

2

1

4

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Wilson et al.

Smilisca baudinii

LC

1

3

Smilisca cyanosticta

NT

4

7

1

12

Smilisca dentata*

EN

5

8

1

14

Smilisca fodiens

LC

2

5

1

8

Tlalocohyla godmani*

VU

5

7

1

13

Tlalocohyla loquax

LC

3

1

7

Tlalocohyla picta

LC

2

5

1

8

Tlalocohyla smithii*

LC

5

1

11

Trachycephalus typhonius

LC

1

2

1

4

Triprion petasatus

LC

4

5

1

10

Family Leiuperidae (1 species)

Engystomops pustulosus

LC

3

2

7

Family Leptodactylidae (2 species)

Leptodactylus fragilis

LC

1

2

5

Leptodactylus melanonotus

LC

1

3

2

6

Family Microhylidae (6 species)

Gastrophryne elegans

LC

2

5

1

8

Gastrophryne mazatlanensis

NE

2

5

1

8

Gastrophryne olivacea

LC

3

5

1

9

Hypopachus barberi

VU

4

5

1

10

Hypopachus ustus

LC

2

4

1

7

Hypopachus variolosus

LC

2

1

4

Family Ranidae (28 species)

Lithobates berlandieri

LC

4

2

1

7

Lithobates brownorum

NE

4

3

1

8

Lithobates catesbeianus

LC

3

6

1

10

Lithobates chichicuahutla*

CR

6

8

1

15

Lithobates chiricahuensis

VU

4

6

1

11

Lithobates dunni*

EN

5

8

1

14

Lithobates forreri

LC

1

3

Lithobates johni*

EN

5

8

1

14

Lithobates lemosespinali*

DD

5

8

1

14

Lithobates macroglossa

VU

4

7

1

12

Lithobates maculatus

LC

3

1

5

Lithobates magnaocularis*

LC

5

6

1

12

Lithobates megapoda*

VU

5

8

1

14

Lithobates montezumae*

LC

5

7

1

13

Lithobates neovolcanicus*

NT

5

7

1

13

Lithobates omiltemanus*

CR

5

7

1

13

Lithobates psilonota*

DD

5

8

1

14

Lithobates pueblae*

CR

6

8

1

15

Lithobates pustulosus*

LC

5

3

1

9

Lithobates sierramadrensis*

VU

5

7

1

13

Lithobates spectabilis*

LC

5

6

1

12

Lithobates tarahumarae

VU

2

5

1

8

Lithobates tlaloci*

CR

6

8

1

15

Lithobates vaillanti

LC

3

5

1

9

Lithobates yavapaiensis

LC

4

7

1

12

Lithobates zweifeli*

LC

5

1

11

August 2013 | Volume 7 | Number 1 | e69

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Conservation reassessment of Mexican amphibians

Rana boylii

NT

3

8

1

12

Rana draytonii

LC

3

6

1

10

Family Rhinophrynidae (1 species)

Rhinophrynus dorsalis

LC

2

5

1

8

Family Scaphiopodidae (4 species)

Scaphiopus couchii

LC

1

3

Spea bombifrons

NE

3

6

1

10

Spea hammondii

LC

3

8

1

12

Spea multiplicata

NE

1

4

1

6

Order Caudata (139 species)

Family Ambystomatidae (18 species)

Ambystoma altamirani*

EN

5

7

1

13

Ambystoma amblycephalum*

CR

6

1

13

Ambystoma andersoni*

CR

6

8

1

15

Ambystoma bombypellum*

CR

6

8

1

15

Ambystoma dumerilii*

CR

6

8

1

15

Ambystoma flavipiperatum*

DD

6

7

1

14

Ambystoma granulosum*

CR

6

7

1

14

Ambystoma leorae*

CR

6

8

1

15

Ambystoma lermaense*

CR

6

8

1

15

Ambystoma mavortium

NE

3

6

1

10

Ambystoma mexicanum*

CR

6

8

1

15

Ambystoma ordinarium*

EN

5

7

1

13

Ambystoma rivulare*

DD

5

7

1

13

Ambystoma rosaceum*

LC

5

8

1

14

Ambystoma silvense*

DD

5

8

1

14

Ambystoma subsalsum*

NE

5

8

1

14

Ambystoma taylori*

CR

6

8

1

15

Ambystoma velasci*

LC

5

4

1

10

Family Plethodontidae (118 species)

Aneides lugubris

LC

3

7

4

14

Batrachoseps major

LC

4

6

4

14

Bolitoglossa alberchi*

LC

6

5

4

15

Bolitoglossa chinanteca

NE

6

8

4

18

Bolitoglossa engelhardti

EN

4

7

4

15

Bolitoglossa flavimembris

EN

4

7

4

15

Bolitoglossa flaviventris

EN

4

5

4

13

Bolitoglossa franklini

EN

4

6

4

14

Bolitoglossa hartwegi

NT

4

12

Bolitoglossa hermosa*

NT

5

7

4

16

Bolitoglossa lincolni

NT

4

5

4

13

Bolitoglossa macrinii*

NT

5

6

4

15

Bolitoglossa mexicana

LC

4

3

4

11

Bolitoglossa mulleri

VU

4

7

4

15

Bolitoglossa oaxacensis*

DD

5

8

4

17

Bolitoglossa occidentalis

LC

4

3

4

11

Bolitoglossa platydactyla*

NT

5

6

4

15

Bolitoglossa riletti*

EN

6

4

16

Bolitoglossa rostrata

VU

4

6

4

14

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Wilson et al.

Bolitoglossa rufescens

LC

1

4

9

Bolitoglossa stuarti

DD

4

7

4

15

Bolitoglossa veracrucis*

EN

6

7

4

17

Bolitoglossa yucatana

LC

4

7

4

15

Bolitoglossa zapoteca*

DD

6

8

4

18

Chiropterotriton arboreus*

CR

6

8

4

18

Chiropterotriton chiropterus*

CR

6

4

16

Chiropterotriton chondrostega*

EN

5

8

4

17

Chiropterotriton cracens*

EN

6

7

4

17

Chiropterotriton dimidiatus *

EN

6

7

4

17

Chiropterotriton lavae*

CR

6

8

4

18

Chiropterotriton magnipes*

CR

6

4

16

Chiropterotriton mosaueri*

DD

6

8

4

18

Chiropterotriton multidentatus *

EN

5

6

4

15

Chiropterotriton orculus*

VU

6

8

4

18

Chiropterotriton priscus*

NT

6

4

16

Chiropterotriton terrestris*

CR

6

8

4

18

Cryptotriton alvarezdeltoroi*

EN

6

8

4

18

Dendrotriton megarhinus*

VU

6

7

4

17

Dendrotriton xolocalcae*

VU

6

8

4

18

Ensatina eschscholtzii

LC

3

7

4

14

Ensatina klauberi

NE

4

6

4

14

Ixalotriton niger*

CR

6

8

4

18

Ixalotriton parvus*

CR

6

8

4

18

Nyctanolis pernix

EN

4

7

4

15

Oedipina elongata

LC

4

7

4

15

Parvimoige townsendi*

CR

5

7

4

16

Pseudoeurycea ahuitzotl*

CR

6

8

4

18

Pseudoeurycea altamontana*

EN

5

8

4

17

Pseudoeurycea amuzga*

DD

6

8

4

18

Pseudoeurycea anitae*

CR

6

8

4

18

Pseudoeurycea aquatica*

CR

6

8

4

18

Pseudoeurycea aurantia*

VU

6

8

4

18

Pseudoeurycea bellii*

VU

5

3

4

12

Pseudoeurycea boneti*

VU

6

7

4

17

Pseudoeurycea brunnata

CR

4

7

4

15

Pseudoeurycea cafetalera

NE

6

7

4

17

Pseudoeurycea cephalica*

NT

5

4

14

Pseudoeurycea cochranae*

EN

6

7

4

17

Pseudoeurycea conanti*

EN

5

7

4

16

Pseudoeurycea firscheini*

EN

6

8

4

18

Pseudoeurycea gadovii*

EN

5

4

13

Pseudoeurycea galaenae*

NT

6

8

4

18

Pseudoeurycea gigantea*

CR

5

7

4

16

Pseudoeurycea goebeli

CR

4

7

4

15

Pseudoeurycea juarezi*

CR

6

7

4

17

Pseudoeurycea leprosa*

VU

5

7

4

16

Pseudoeurycea lineola*

EN

5

4

14

Pseudoeurycea longicauda*

EN

5

8

4

17

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Conservation reassessment of Mexican amphibians

Pseudoeurycea lynchi*

CR

5

8

4

17

Pseudoeurycea maxima*

DD

5

8

4

17

Pseudoeurycea melanomolga*

EN

6

4

16

Pseudoeurycea mixcoatl*

DD

6

8

4

17

Pseudoeurycea mixteca*

LC

5

8

4

17

Pseudoeurycea mystax*

EN

6

8

4

18

Pseudoeurycea naucampatepetl*

CR

6

7

4

17

Pseudoeurycea nigromaculata*

CR

5

8

4

17

Pseudoeurycea obesa*

DD

6

8

4

18

Pseudoeurycea orchileucos*

EN

6

8

4

18

Pseudoeurycea orchimelas*

EN

6

7

4

17

Pseudoeurycea papenfussi*

NT

6

7

4

17

Pseudoeurycea praecellens*

CR

6

8

4

18

Pseudoeurycea quetzalanensis*

DD

6

7

4

17

Pseudoeurycea rex

CR

4

12

Pseudoeurycea robertsi*

CR

6

8

4

18

Pseudoeurycea ruficauda*

DD

6

8

4

18

Pseudoeurycea saltator*

CR

6

8

4

18

Pseudoeurycea scandens*

VU

6

7

4

17

Pseudoeurycea smithi*

CR

5

6

4

15

Pseudoeurycea tenchalli*

EN

6

7

4

17

Pseudoeurycea teotepec*

EN

6

8

4

18

Pseudoeurycea tlahcuiloh*

CR

6

7

4

17

Pseudoeurycea tlilicxitl*

DD

5

8

4

17

Pseudoeurycea unguidentis*

CR

6

7

4

17

Pseudoeurycea werleri*

EN

6

7

4

17

Thorius adelos*

EN

6

8

4

18

Thorius arbor eus*

EN

6

8

4

18

Thorius aureus*

CR

6

7

4

17

Thorius boreas*

EN

6

8

4

18

Thorius dubitus*

EN

5

7

4

16

Thorius grandis*

EN

6

5

4

15

Thorius infernal is*

CR

6

8

4

18

Thorius insperatus*

DD

6

8

4

18

Thorius lunaris*

EN

6

8

4

18

Thorius macdougalli*

VU

6

4

16

Thorius magnipes*

CR

6

7

4

17

Thorius minutissimus*

CR

6

7

4

17

Thorius minydemus*

CR

6

8

4

18

Thorius munificus*

CR

6

8

4

18

Thorius narismagnus*

CR

6

8

4

18

Thorius narisovalis*

CR

6

7

4

17

Thorius omiltemi*

EN

6

8

4

18

Thorius papaloae*

EN

6

7

4

17

Thorius pennatulus*

CR

5

6

4

15

Thorius pulmonaris*

EN

6

7

4

17

Thorius schmidti*

EN

6

7

4

17

Thorius smithi*

CR

6

7

4

17

Thorius spilogaster*

CR

6

7

4

17

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Wilson et al.

Thorius troglodytes*

EN

6

4

16

Family Salamandridae (1 species)

Notophthalmus meridionalis

EN

2

8

1

12

Family Sirenidae (2 species)

Siren intermedia

LC

3

8

1

12

Siren lacertina

LC

3

8

1

12

Order Gymnophiona (2 species)

Family Dermophiidae (2 species)

Dermophis mexicanus

VU

4

3

4

11

Dermophis oaxacae*

DD

5

3

4

12

Amphib. Reptile Conserv. | http://amphibian-reptile-conservation.org 1 27

August 2013 | Volume 7 | Number 1 | e69

Crotalus tancitarensis. The Tancftaro cross-banded mountain rattlesnake is a small species (maximum recorded total length = 434

mm) known only from the upper elevations (3,220-3,225 m) of Cerro Tancftaro, the highest mountain in Michoacan, Mexico,

where it inhabits pine-fir forest (Alvarado and Campbell 2004; Alvarado et al. 2007). Cerro Tancftaro lies in the western portion of

the Transverse Volcanic Axis, which extends across Mexico from Jalisco to central Veracruz near the 20°N latitude. Its entire range

is located within Parque Nacional Pico de Tancftaro (Campbell 2007), an area under threat from manmade fires, logging, avocado

culture, and cattle raising. This attractive rattlesnake was described in 2004 by the senior author and Jonathan A. Campbell, and

placed in the Crotalus intermedins group of Mexican montane rattlesnakes by Bryson et al. (2011). We calculated its EVS as 19,

which is near the upper end of the high vulnerability category (see text for explanation), its IUCN status has been reported as Data

Deficient (Campbell 2007), and this species is not listed by SEMARNAT. More information on the natural history and distribution

of this species is available, however, which affects its conservation status (especially its IUCN status; Alvarado-Dfaz et al. 2007).

We consider C. tancitarensis one of the pre-eminent flagship reptile species for the state of Michoacan, and for Mexico in general.

Photo by Javier Alvarado-Diaz.

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128

Commons Attribution-NonCommercial-NoDerivs 3.0 Unported License, which permits unrestricted use for

non-commercial and education purposes only provided the original author and source are credited.

Amphibian & Reptile Conservation 7(1): 128-170.

Patterns of physiographic distribution and conservation

status of the herpetofauna of Michoacan, Mexico

Wavier Alvarado-Diaz, 2 lreri Suazo-Ortuno,

3 Larry David Wilson, and 4 Oscar Medina-Aguilar

12A Instituto de Investigaciones sobre los Recursos Naturales, Universidad Michoacana de San Nicolas de Hidalgo, Av. San Juanito Itzicuaro s/n

Col. Nva. Esperanza, Morelia, Michoacan, MEXICO, 58337 ''Centro Zamorano de Biodiversidad, Escuela Agricola Panamericana Zamorano,

Departamento de Francisco Morazdn, HONDURAS

Abstract . — At their respective levels, the country of Mexico and the state of Michoacan are major cen-

ters of herpetofaunal diversity and endemicity. Three of us (JAD, ISO, OMA) conducted extensive

fieldwork in Michoacan from 1998 to 2011, and recorded 169 herpetofaunal species. With additional

species reported in the literature and specimens available in scientific collections, the number of

species in Michoacan has grown to 215. We examined the distribution of these species within the

framework of the five physiographic provinces within the state, i.e., the Coastal Plain, the Sierra

Madre del Sur, the Balsas-Tepalcatepec Depression, the Transverse Volcanic Axis, and the Cen-

tral Plateau, which briefly are characterized geomorphologically and climatically. The herpetofauna

consists of 54 amphibians and 161 reptiles (17.5% of the total for Mexico), classified in 38 families

and 96 genera. Almost one-half of Michoacan’s herpetofaunal species occur in a single physio-

graphic province, and the percentage of species decreases with an increase in the number of prov-

inces. The province with the most species is the Sierra Madre del Sur, with slightly fewer numbers

in the Balsas-Tepalcatepec Depression and the Transverse Volcanic Axis. An intermediate number

is found in the Coastal Plain, and the lowest in the Central Plateau province. We constructed a Co-

efficient of Biogeographic Resemblance matrix and found the greatest degree of herpetofaunal re-

semblance between the Balsas-Tepalcatepec Depression and the Sierra Madre del Sur. The greatest

resemblance of the Coastal Plain herpetofauna is to that of Balsas-Tepalcatepec Depression, that

of the Transverse Volcanic Axis to that of the Central Plateau, and vice versa. Of the species limit-

ed to one physiographic province, 47 occur only in the Transverse Volcanic Axis, 23 in the Coastal

Plain, 15 in the Balsas-Tepalcatepec, 14 in the Sierra Madre del Sur, and one in the Central Plateau.

We employed three systems for determining the conservation status of the herpetofauna of Micho-

acan: SEMARNAT, IUCN, and EVS. Almost one-half of the species in the state are not assessed by

the SEMARNAT system, with the remainder allocated to the Endangered (four species), Threatened

(31), and Special Protection (79) categories. The IUCN system provides an assessment for 184 of

the 212 native species, allocating them to the Critically Endangered (five species), Endangered (10),

Vulnerable (12), Near Threatened (four), Least Concern (127), and Data Deficient (26) categories.

The EVS system provides a numerical assessment for all of the native non-marine species (four ma-

rine species occur in the state), with the values ranging from three to 19. The resulting 208 species

were placed in low, medium, and high categories of vulnerability, as follows: low (17 amphibians,

39 reptiles); medium (23 amphibians, 45 reptiles); and high (13 amphibians, 71 reptiles). The EVS

system is the only one that provides an assessment for all the species (except for the four marine

taxa), as well as the only one that considers the distributional status of Michoacan’s herpetofauna

(state-level endemic, country-level endemic, and non-endemic). Furthermore, the values indicate

that ca. 40% of the state’s herpetofauna is categorized at the highest level of environmental vul-

nerability. Based on these conclusions, we provide recommendations for protecting Michoacan’s

herpetofauna in perpetuity.

Key words. Amphibians, reptiles, physiographic provinces, conservation status, recommendations

Correspondence. Emails: 1 jvr.alvarado@gmail.com (Corresponding author) 2 ireri. suazo@gmail.com

3 bufodoc@aol. com 4 mineo_osc@hotmail. com

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129

Physiographic distribution and conservation of Michoacan herpetofauna

Resumen . — Mexico es un importante centro de diversidad y endemismo herpetofaunistico y el es-

tado de Michoacan tambien presenta estas caracteristicas. Durante el periodo de 1998-2011, tres

de nosotros (JAD, ISO, OMA) conducimos un extenso trabajo de campo en Michoacan, registrando

169 especies de anfibios y reptiles. Con la adicion de especies reportadas en la literatura y los

registros disponibles en colecciones cientificas, el numero total de especies de la herpetofauna

michoacana es de 215. Examinamos la distribution de estas especies en Michoacan, considerando

las cinco provincias fisiograficas representadas en el Estado: la Llanura Costera, la Sierra Madre

del Sur, la Depresion del Balsas-Tepalcatepec, el Eje Volcanico Transversal, y la Meseta Central,

las que de manera resumida son caracterizadas en base a su geomorfologia y clima. La herpeto-

fauna consiste de 54 anfibios y 161 reptiles (17.5% del total de Mexico), clasificadas en 38 familias

y 96 generos. Casi la mitad de las especies de la herpetofauna de Michoacan ocurre en una sola

provincia fisiografica, con un cada vez menor porcentaje de especies a medida que el numero de

provincias se incrementa. El mayor numero de especies se encuentra en la Sierra Madre del Sur,

con cifras ligeramente menores en la Depresion del Balsas-Tepalcatepec y el Eje Volcanico Trans-

versal. Un numero intermedio de especies se encuentra en la provincia Planicie Costera y el menor

numero se encuentra en la provincia Meseta Central. Implementamos una matriz del Coeficiente de

Semejanza Biogeografica, la que muestra que el mayor grado de semejanza herpetofaunistica se

encuentra entre la Depresion del Balsas-Tepalcatepec y la Sierra Madre del Sur. La mayor similitud

de la herpetofauna de la Planicie Costera es con la herpetofauna de la Depresion Balsas-Tepal-

catepec, la del Eje Volcanico Transversal con la de la Meseta Central y viceversa. De las especies

restringidas a una sola provincia fisiografica, 47 ocurren solamente en el Eje Volcanico Transversal,

23 en la Planicie Costera, 15 en la Depresion del Balsas-Tepalcatepec, 14 en la Sierra Madre del

Sury y una en la Meseta Central. Usamos tres sistemas para determinar el estado de conservacion:

SEMARNAT, UICN, y EVS. Casi la mitad de las especies de Michoacan no han sido evaluadas por

el sistema de SEMARNAT, y las evaluadas han sido asignadas a las categorias de Peligro (cuatro

especies), Amenazadas (31), y Proteccion Especial (79). El sistema de la UICN ha evaluado 184 de

las 212 especies nativas de Michoacan, asignadas a las siguientes categorias: Peligro Critico (cinco

especies), En Peligro (10), Vulnerable (12), Casi Amenazado (cuatro), Preocupacion Menor (127), y

Datos Insuficientes (26). El sistema EVS proporciona una evaluacion numerica para todas las espe-

cies nativas que no son marinas (cuatro especies marinas ocurren en el estado), con valores de tres

a 18. Las 209 especies evaluadas mediante el EVS fueron asignadas a las categorias de baja, media

y alta vulnerabilidad de la siguiente manera: baja (17 anfibios, 39 reptiles); media (23 anfibios, 45

reptiles); y alta (13 anfibios, 71 reptiles). El sistema EVS es el unico de los tres que proporciona una

evaluacion de todas las especies (excepto para los cuatro taxa marinos) y el unico que considera

el estado distribucional de los componentes de la herpetofauna de Michoacan (endemico a nivel

estatal, endemico a nivel de pais, y no endemico). Ademas, los valores muestran que cerca del 40%

de la herpetofauna del estado se encuentra en la categoria mas alta de vulnerabilidad ambiental.

En base a estas conclusiones, proponemos recomendaciones para la proteccion a perpetuidad de

la herpetofauna de Michoacan.

Palabras claves. Anfibios, reptiles, provincias fisiograficas, estatus de conservacion, recomendaciones

Citation: Alvarado-Dfaz J, Suazo-Ortuno I, Wilson LD, Medina-Aguilar O. 2013. Patterns of physiographic distribution and conservation status of the

herpetofauna of Michoacan, Mexico. Amphibian & Reptile Conservation 7(1): 128-170(e71).

The publication of On the Origin of Species in 1859 is

a recognized watershed in biological science. Perhaps

the greatest threat to Western ideology was not the com-

mon origin of all beings, as is assumed, but rather the

possibility of a common ending: that all beings, humans

among them were subjected to the same forces and vul-

nerabilities.

Chernela 2012: 22.

Amphib. Reptile Conserv. | http://amphibian-reptile-conservation.org

Introduction

Mesoamerica is one of the principal biodiversity hotspots

in the world (Wilson and Johnson 2010), and the coun-

try of Mexico comprises about 79% of the land surface

of Mesoamerica (CIA World Factbook). The document-

ed amphibian fauna of Mexico currently consists of

379 species, including 237 anurans, 140 salamanders,

and two caecilians (Wilson et al. 2013b). Based on this

130

September 2013 | Volume 7 | Number 1 | e71

Alvarado-Diaz et al.

Incilius pisinnus. The Michoacan toad is a state endemic, with a distribution in the Balsas-Tepalcatepec Depression and the Sierra

Madre del Sur. Its EVS was estimated as 15, which is unusually high for a bufonid anuran, its IUCN ranking has been judged as

Data Deficient, and a SEMARNAT status has not been provided. This individual is from Apatzingan, Michoacan.

Photo by Oscar Medina- Aguilar.

Eleutherodactylus rufescens. The blunt-toed chirping frog is endemic to the Sierra de Coalcoman region of the Sierra Madre del

Sur. Its EVS has been assessed as 17, placing this species in the middle of the high vulnerability category, this frog is considered as

Critically Endangered by IUCN, and as a Special Protection species by SEMARNAT. This individual was found at Dos Aguas in

the Sierra de Coalcoman (Sierra Madre del Sur) in Michoacan. Photo by Oscar Medina- Aguilar.

September 2013 | Volume 7 | Number 1 | e71

Amphib. Reptile Conserv. | http://amphibian-reptile-conservation.org

131

Physiographic distribution and conservation of Michoacan herpetofauna

figure, Mexico is the country with the 5 th largest number

of amphibian species in the world (Llorente-Bousquets

and Ocegueda 2008; Stuart et al. 2010a), after Brazil,

Colombia, Ecuador, and Peru. The country also is in-

habited by 849 species of reptiles, including 798 squa-

mates, 48 turtles, and three crocodylians (Wilson et

al. 2013a), which globally is the second largest reptile

fauna (Llorente-Bousquets and Ocegueda 2008), after

Australia. The total number of 1,227 species makes the

Mexican herpetofauna the second largest in the world

(Llorente-Bousquets and Ocegueda 2008), comprising

7.3% of the global herpetofauna (7,044 amphibian spe-

cies, according to the Amphibian Species of the World

website, accessed 21 Lebruary 2013, and 9,766 reptile

species, according to the Reptile Database website, also

accessed 21 Lebruary 2013, for a total of 16,810).

Beyond its highly significant herpetofaunal diversity,

Mexico also contains an amazing amount of endemicity.

Currently, 254 of 379 (67.0%) of the known amphibi-

an species and 480 of 849 (56.5%) of the known reptile

species are endemic (Wilson et al. 2013a,b). The com-

bined figure for both groups is 734 species (59.8%), a

percentage 2.4 times as high as the next highest rate of

endemicity for the Central American countries (24.8%

for Honduras; Townsend and Wilson 2010).

Michoacan (the formal name is Michoacan de Ocam-

po) is the 16 th largest state in Mexico, with an area of

58,599 km 2 (www.en.wikipedia.org/wiki/List_of_Mexi-

can_states_by_area), which comprises about 3.0% of the

country’s land surface. The state is located in southwest-

ern Mexico between latitudes 20°23'44" and 18°09'49"

N and longitudes 100°04'48” and 103°44'20" W, and

is bounded to the northwest by Colima and Jalisco, to

the north by Guanajuato and Queretaro, to the east by

Mexico, and to the southeast by Guerrero. Michoacan is

physiographically and vegetationally diverse, inasmuch

as elevations range from sea level to 3,840 m (at the top

of Volcan Tancftaro). The state encompasses a portion of

the Pacific coastal plain, a long stretch of the Balsas-Te-

palcatepec Depression, a segment of the Sierra Madre

del Sur called the Sierra de Coalcoman, and a significant

portion of the Transverse Volcanic Axis.

Mexico is known for its high level of herpetofaunal

endemism, but compared with the country the herpeto-

fauna of Michoacan is several percentage points higher,

with a number of the country endemics limited in distri-

bution to the state (see below). Any attempt to assess the

conservation status of a herpetofaunal group depends on

an accurate accounting of the distribution and composi-

tion of the species involved. Thus, our objectives with

this study are to update the list of amphibians and rep-

tiles in Michoacan, to discuss their distribution among

the physiographic provinces, and to use these data to

gauge the conservation status of the entire herpetofau-

na using various measures. Linally, based on our con-

servation assessment, we provide recommendations to

enhance current efforts to protect the state’s amphibians

and reptiles.

Diaglena spatulata. The shovel-headed treefrog is distributed along the Pacific coastal lowlands from Sinaloa to Oaxaca, and thus

is a Mexican endemic hylid anuran. In Michoacan, it occurs in the Balsas-Tepalcatepec Depression and along the Coastal Plain. Its

EVS was gauged as 13, placing it at the upper end of the medium vulnerability category, IUCN has assessed this anuran as Least

Concern, and it is not listed by SEMARNAT. This individual was photographed at the Reserva de la Biosfera Chamela-Cuixmala

on the coast of Jalisco. Photo by Oscar Medina- Aguilar.

September 2013 | Volume 7 | Number 1 | e71

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132

Alvarado-Dfaz et al.

Materials and Methods

1. Sampling procedures

From 1998 to 2011, three of us (JAD, ISO, OMA) con-

ducted fieldwork in 280 localities (58 municipalities) of

Michoacan, representing all of the state’s physiographic

provinces, with significant attention paid to poorly sam-

pled areas, as part of the “Diversidad Herpetofaunfstica

del Estado de Michoacan” project undertaken by person-

nel from the Laboratorio de Herpetologla of the Instituto

de Investigaciones sobre los Recursos Naturales (INI-

RENA) of the Universidad Michoacana de San Nicolas

de Hidalgo (UMSNH). Importantly, due to unsafe

conditions in certain parts of the state in recent years,

large areas have not been explored. During each visit

to the sampling sites, we used visual encounter surveys

(Crump and Scott 1994) to locate amphibians and rep-

tiles during the day and at night. This work was conduct-

ed under scientific collecting permits (DGVS/FAUT-

0113), and used the collection techniques described by

Casas et al. (1991). In cases where we could not identify

individuals in the field, they were sacrificed and subse-

quently deposited in the herpetological collections of

INIRENA-UMSNH. We identified specimens by using

taxonomic keys and other information in Smith and Tay-

lor (1945, 1948, 1950), Duellman (1961, 1965, 2001),

Casas- Andreu and McCoy (1979), Ramfrez-Bautista

(1994), Flores- Villela et al. (1995), and Huacuz (1995),

and updated scientific names by using Flores-Villela and

Canseco-Marquez (2004), Faivovich et al. (2005), Wil-

son and Johnson (2010), and Wilson et al. (2013a,b).

2. Updating the herpetofaunal list

In addition to the specimens recorded during the field-

work, the list of species was augmented using material

donated by others. We also used records from the Colec-

cion Nacional de Anfibios y Reptiles-UNAM (CNAR),

the California Academy of Sciences (CAS), the Universi-

ty of Colorado Museum of Natural History, Herpetology

Collection (CUMNH), the Museum of Natural Sciences,

Louisiana State University (LSUMZ), the Field Muse-

um of Natural History (FMNH), and the Royal Ontario

Museum (ROM). Additionally, we included records for

Michoacan from the Catalogo de la Biodiversidad en

Michoacan (SEDUE [Secretarfa de Desarrollo Urbano y

Ecologfa], UMSNH 2000), la Biodiversidad en Micho-

acan Estudio de Estado (Villasenor 2005), various dis-

tribution notes published in Herpetological Review and

otherwise posted at the IUCN Red List website, as well

as data presented by Flores-Villela and Canseco-Marquez

(2004), Vargas-Santamarfa and Flores-Villela (2006),

Gonzalez-Hemandez and Garza-Castro (2006), Medi-

na- Aguilar et al. (20 1 1 ) , and Torres (20 11). We follow the

taxonomy used in Wilson (2013 a, b), with the exception

Amphib. Reptile Conserv. | http://amphibian-reptile-conservation.org 133

of the deletion of the nominal species Anolis schmidti,

which recently was synonymized by Nieto et al. (2013).

3. Systems for determining

conservation status

We used the following three systems to determine the

conservation status of the 212 native species of amphibi-

ans and reptiles in Michoacan: SEMARNAT, IUCN, and

EVS. The SEMARNAT system, established by the Sec-

retarfa de Medio Ambiente y Recursos Naturales, em-

ploys three categories — Endangered (P), Threatened (A),

and Subject to Special Protection (Pr). The results of the

application of this system are reported in the NORMA

Oficial Mexicana NOM-059-SEMARNAT-2010 (www.

semarnat.gob.mx). For species not assessed by this sys-

tem, we use the designation “No Status.”

The IUCN system is utilized widely to assess the con-

servation status of species on a global basis. The catego-

ries used are explained in the document IUCN Red List

of Categories and Criteria (2010), and include Extinct

(EX), Extinct in the Wild (EW), Critically Endangered

(CR), Endangered (EN), Vulnerable (VU), Near Threat-

ened (NT), Least Concern (LC), Data Deficient (DD),

and Not Evaluated (NE). The categories Critically En-

dangered, Endangered, and Vulnerable collectively are

termed “threat categories,” to distinguish them from the

other six.

The EVS system was developed initially for use in

Honduras by Wilson and McCranie (2004), and subse-

quently was used in several chapters on Central American

countries in Wilson et al. (2010). Wilson et al. (2013a, b)

modified this system and explained its use for the am-

phibians and reptiles of Mexico, and we follow their pre-

scriptions. The EVS measure is not designed for use with

marine species (e.g., marine turtles and sea snakes), and

generally is not applied to non-native species.

Physiography and Climate

1. Physiographic provinces

Based on geological history, morphology, structure, hy-

drography, and soils, five physiographic provinces can

be recognized within the state of Michoacan, including

the Pacific Coastal Plain, the Sierra Madre del Sur, the

Balsas-Tepalcatepec Depression, the Transverse Volcanic

Axis, and the Central Plateau (Fig. 1). The Coastal Plain

province comprises a narrow strip of land between the Pa-

cific Ocean and the Sierra Madre del Sur, and consists of

small alluvial plains extending from the mouth of the Rio

Balsas to the east and the Rio Coahuayana to the west.

The Sierra Madre del Sur (Sierra de Coalcoman) lies

between the Coastal Plain and the Balsas-Tepalcatepec

Depression, extends for over 100 km in a north-

west-southeast direction, and contains elevations reach-

ing about 2,200 m. The Balsas-Tepalcatepec Depression

September 2013 | Volume 7 | Number 1 | e71

Physiographic distribution and conservation of Michoacan herpetofauna

is located between the Sierra Madre del Sur to the south-

west and the Transverse Volcanic Axis to the northeast.

This intermontane area is a broad structural basin that

lies at elevations ranging from 200 to 700 m. As noted

by Duellman (1961 : 10), “the western part of this basin. . .

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.” The Transverse Volcanic Axis

is located to the south of the Central Plateau and crosses

Mexico at about the 20 th parallel. The region is composed

of volcanic ejecta and is volcanically active. This area is

home to Mexico’s highest mountains, such as Pico de

Orizaba (5,636 m) and Popocatepetl (5,426 m), which

in Michoacan is represented by Pico de Tancftaro, with

an elevation of 3,850 m. In addition, several endorheic

lakes are located in this province, including Patzcuaro,

Zirahuen, and Cuitzeo. The Central Plateau is a vast ta-

bleland bordered on the south by the Transverse Volca-

nic Axis, on the west by the Sierra Madre Occidental, on

the east by the Sierra Madre Oriental, and on the north

by the Rio Bravo (Rio Grande). Elevations in this prov-

ince range from 1,100 m in the northern portion of the

country to 2,000 m. In Michoacan, this province is rep-

resented by a relatively small area (3,905 km 2 ) along the

northern border of the state; the Rio Lerma flows from

it, and empties into the Pacific Ocean (Duellman 1961).

Amphib. Reptile Conserv. | http://amphibian-reptile-conservation.org 134

2. Climate

Given its location in the tropical region of Mexico, south

of the Tropic of Cancer, temperatures in Michoacan vary

as a consequence of differences in elevation and the ef-

fects of prevailing winds. To illustrate variation in ambi-

ent temperatures in the state, we extracted data for one

locality from each of the five physiographic provinces

from the Servicio Meteorologico Nacional, Michoacan

and placed them in Table 1 . These data are organized in

the table from top to bottom based on the elevation of the

localities (from low to high). As expected, a decrease in

the mean annual temperature occurs from lower to high-

er elevations. The same pattern is seen for annual mini-

mum and maximum temperatures, except for the Coastal

Plain compared to the Balsas-Tepalcatepec Depression

(33.0 vs. 34.4 °C).

As expected in the tropics, relatively little tempera-

ture variation occurs throughout the year. The differenc-

es between the low and high mean monthly temperatures

(in °C) for the localities in the five physiographic prov-

inces are as follows: Coastal Plain (Lazaro Cardenas,

50 m) = 1.9; Balsas-Tepalcatepec Depression (Apatzingan,

320 m) = 5.5; Sierra Madre del Sur (Coalcoman, 1,100 m)

= 5.2; Central Plateau (Morelia, 1,915 m) = 5.9; and

Transverse Volcanic Axis (Patzcuaro, 2,035 m) = 6.6.

September 2013 | Volume 7 | Number 1 | e71

Alvarado-Diaz et al.

The lowest mean monthly temperatures are for January,

and the highest for May or June. Essentially the same

pattern occurs with minimum and maximum monthly

temperatures, except for minor departures in a few areas

(Table 1).

The highest mean monthly temperature (34.4 °C) is

at Apatzingan in the Balsas-Tepalcatepec Depression.

Duellman (1961) stated that the highest mean annu-

al temperatures (29.3 °C) in this depression have been

recorded at Churumuco (251 m), as reported by Con-

treras (1942). More recent data at the Servicio Meteo-

rologico Nacional website for Michoacan indicates that

the highest daily temperature of 46 °C was recorded at

this locality on 9 April 1982. At the other extreme are

temperatures on the peak of Volcan Tancftaro, where the

mean annual temperature is less than 10 °C and it snows

during the winter.

In tropical locales, heavy or light precipitation typ-

ically occurs during the rainy and dry seasons, respec-

tively. In Michoacan, the rainy season extends from June

to October, when 80% or more of the annual precipita-

tion is deposited. As with temperature data, we extract-

ed information on mean annual precipitation and vari-

ation in monthly precipitation recorded at one locality

for each of the five physiographic provinces, and placed

the data in Table 2. The results demonstrate that at each

locality the highest amount of precipitation occurs from

June to October. The percentage of annual precipitation

Table 1. Monthly minimum, mean (in parentheses), maximum, and annual temperature data (in °C) for the physiographic provinces

of Michoacan, Mexico. Localities and their elevation for each of the provinces are as follows: Coastal Plain (Lazaro Cardenas, 50

m); Balsas-Tepalcatepec Depression (Apatzingan, 320 m); Sierra Madre del Sur (Coalcoman de Vazquez Pallares, 1,100 m); Central

Plateau (Morelia, 1,915 m); Transverse Volcanic Axis (Patzcuaro, 2,035 m). Data (1971-2000) from the Sistema Meteorologico Nacional,

Michoacan (smn.cna.gob.mx/index).

Physiographic

Province

Jan.

Feb.

March

April

May

June

July

Aug.

Sept.

Oct.

Nov.

Dec.

Annual

Coastal Plain

20.6

(26.6)

32.6

20.6

(26.8)

33.1

20.8

(27.0)

33.2

21.2

(27.3)

33.5

22.8

(28.3)

33.8

23.9

(28.5)

33.1

23.4

(28.0)

32.7

23.7

(28.1)

32.6

23.3

(27.7)

32.0

23.5

(28.1)

32.6

22.7

(27.9)

33.2

21.1

(27.1)

33.2

22.3

(27.6)

33.0

Balsas-

Tepalcatepec

Depression

16.7

(24.6)

32.5

17.6

(25.9)

34.1

19.1

(27.7)

36.3

20.7

(29.2)

37.6

22.3

(30.3)

38.3

22.7

(29.1)

35.6

21.6

(27.3)

33.1

21.6

(27.3)

33.1

21.7

(27.3)

33.0

21.5

(27.7)

33.8

19.5

(26.4)

33.3

17.7

(25.1)

32.5

20.2

(27.3)

34.4

Sierra Madre

del Sur

10.2

(19.9)

29.7

10.7

(20.8)

30.9

11.6

(22.1)

32.7

12.3

(23.5)

34.6

14.3

(24.8)

35.3

17.9

(25.1)

32.4

18.2

(24.1)

30.1

17.4

(23.8)

30.2

17.7

(23.8)

30.0

16.7

(23.7)

30.8

13.9

(22.2)

30.4

11.9

(21.0)

30.0

14.4

(22.9)

31.4

Central Plateau

6.8

(15.8)

24.7

7.6

(17.0)

26.4

9.6

(19.0)

28.4

11.1

(20.4)

29.7

12.6

(21.7)

30.9

13.3

(21.2)

29.1

12.8

(19.6)

26.5

13.1

(19.8)

26.4

12.9

(19.4)

26.0

11.3

(18.7)

26.1

9.3

(17.7)

26.2

7.3

(16.4)

25.5

10.6

(18.9)

27.2

Transverse

Volcanic Axis

3.3

(12.9)

22.5

4.0

(14.1)

24.1

5.4

(16.0)

26.6

7.3

(17.8)

28.2

9.4

(19.1)

28.7

12.5

(19.5)

26.4

12.0

(18.0)

23.9

11.9

(18.0)

24.1

11.5

(17.7)

23.9

9.2

(16.7)

24.1

5.9

(14.8)

23.7

4.3

(13.4)

22.6

8.1

(16.5)

24.9

Table 2. Monthly and annual precipitation data (in mm.) for the physiographic provinces of Michoacan, Mexico. Localities and

their elevation for each of the provinces are as follows: Coastal Plain (Lazaro Cardenas, 50 m); Sierra Madre del Sur (Coalcoman

de Vazquez Pallares, 1,100 m); Balsas-Tepalcatepec Depression (Apatzingan, 320 m); Transverse Volcanic Axis (Patzcuaro, 2,035

m); Central Plateau (Morelia, 1,915 m). The shaded area indicates the months of the rainy season. Data taken from Servicio

Meteorologico Nacional, Michoacan (smn.cna.gob.mx/index).

Physiographic

Province

Jan.

Feb.

March

Apr.

May

June

July

Aug.

Sept.

Oct.

Nov.

Dec.

Annual

Coastal Plain

7.5

0.4

1.0

0.0

17.0

240.4

269.0

257.0

374.2

150.1

23.7

34.0

1,374.3

Balsas-

Tepalcatepec

Depression

19.8

22.0

9.0

2.5

24.1

138.0

167.9

160.8

133.6

78.8

36.9

15.3

808.7

Sierra Madre del

Sur

33.7

42.8

24.8

7.8

37.2

272.2

284.1

258.0

225.7

166.8

93.0

42.1

1,488.2

Central Plateau

15.8

5.6

7.5

9.9

37.9

146.5

166.1

167.8

131.6

51.6

10.4

4.2

754.9

Transverse

Volcanic Axis

27.1

5.0

5.1

9.7

37.8

150.3

219.6

204.1

157.9

71.2

17.6

13.4

918.8

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135

Physiographic distribution and conservation of Michoacan herpetofauna

during this period ranges from 81.1% at Coalcoman in

the Sierra Madre del Sur to 93.9% at Lazaro Cardenas

on the Coastal Plain (mean 86.9%). Generally, the driest

month is April (except on the Central Plateau, where it

is December) and the wettest month is July (except on

the Central Plateau, where it is August). Annual precip-

itation is lowest on the Central Plateau, with 754.9 mm

for the capital city of Morelia, and highest at Coalcoman

in the Sierra Madre del Sur, with 1,488.2 mm (Table 2).

Composition of the Herpetofauna

Field surveys and a review of the published literature and

databases yielded a total of 215 species of amphibians

and reptiles for the state of Michoacan (54 amphibians,

161 reptiles). Of the amphibians, 44 are anurans (81.1%,

including the non-native Lithobates catesbeianus ), nine

are salamanders (17.0%), and one is a caecilian (1.9%).

Of the 161 reptiles, 153 are squamates (95.0%, including

the non-native Hemidactylus frenatus and Ramphoty-

phlops braminus ), seven are turtles (4.4%), and one is a

crocodylian (0.6%). The number of species occurring in

Michoacan is 17.5% of the total for the Mexican herpe-

tofauna (1,227 species; Wilson et al. 2013a,b; Table 3).

Table 3. Composition of the amphibians and reptiles of Mexico

and the state of Michoacan. In each column, the number to the

left is that indicated in Wilson et al. (2013a,b) for the country

of Mexico; the number to the right is that recorded in this study

for the state of Michoacan. These numbers include the marine

and non-native taxa.

Taxa

Families

Genera

Species

Anura

11/9

35/19

237/44

Caudata

4/2

15/2

139/9

Gymnophiona

1/1

2/1

Subtotals

16/12

51/22

378/54

Squamata

31/21

139/68

798/153

Testudines

9/4

18/5

48/7

Crocodylia

2/1

3/1

Subtotals

42/26

159/74

849/161

Totals

58/38

210/96

1,227/215

1. Families

The herpetofauna of Michoacan (215 species) is clas-

sified in 38 families (65.5% of the number in Mexico),

with the 54 species of amphibians in 12 of the 16 fami-

lies known from the country (75.0%; Wilson et al. 2013a,

b; Table 3). About one-half of the amphibian species are

classified in one of three families (Hylidae, Ranidae, and

Amphib. Reptile Conserv. | http://amphibian-reptile-conservation.org 136

Ambystomatidae). The 161 species of reptiles are clas-

sified in 26 fa mili es (including the family Gekkonidae,

occupied by a single non-native species, H. frenatus, and

the family Typhlopidae, occupied by a single non-native

species, R. braminus ), 61.9% of the 42 families found in

Mexico (Wilson et al. 2013a; Table 3). One-half of the

species of reptiles in the state are classified in one of three

families (Phrynosomatidae, Colubridae, and Dipsadidae).

2. Genera

The herpetofauna of Michoacan is represented by 96

genera (45.7% of the 210 known from Mexico; Wilson et

al. 2013a,b), with the amphibians composed of 22 genera

(43.1% of the 51 known from the country). The reptiles

consist of 74 genera (46.5% of the country total of 159).

The largest amphibian genera are Incilius (four species),

Craugastor (five), Eleutherodactylus (five), Lithobates

(11), and Ambystoma (seven). Together, these 32 species

comprise 59.3% of the amphibians known from the state

(Table 3). The most sizable reptilian genera are Scelopo-

rus (16), Geophis (nine), Thamnophis (nine), Crotalus

(eight), Aspidoscelis (seven), Phyllodactylus (five),

Plestiodon (five), Coniophanes (five), and Leptodeira

(five). These 69 species constitute 42.9% of the reptiles

known from the state (Table 3).

3. Species

Mexico is home to 378 amphibian species, of which

54 (14.3%) occur in Michoacan (Table 3). Anurans are

better represented in the state (18.6% of 237 Mexican

species) than salamanders (6.5% of 139). Only two cae-

cilian species are known from Mexico, and one occurs

in Michoacan (50.0%). Mexico also is inhabited by 849

reptile species, of which 161 (19.0%) are found in Mi-

choacan. Squamates are somewhat better represented in

the state (19.2% of 798) than turtles (14.6% of 48). Only

three crocodylian species occur in Mexico, and one is

found in Michoacan (Table 3).

Patterns of Physiographic Distribution

We recognize five physiographic provinces in Micho-

acan (Fig. 1), and their herpetofaunal distribution is in-

dicated in Table 4 and summarized by family in Table 5.

Of the 215 species recorded from the state, 100

(46.5%, 24 amphibians, 76 reptiles) are limited in dis-

tribution to a single physiographic province. In addi-

tion, 64 (29.8%, 15 amphibians, 49 reptiles) are known

from two provinces, 37 (17.2%, eight amphibians, 29

reptiles) from three, 11 (5.1%, seven amphibians, four

reptiles) from four, and only three (1.4%, 0 amphibians,

three reptiles) from all five provinces (Table 4). In both

amphibians and reptiles, the number of species steadily

drops from the lowest to the highest occupancy figures.

This distributional feature is significant to conservation

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Alvarado-Diaz et al.

efforts, inasmuch as the more restricted their distribu-

tion the more difficult it will be to provide species with

effective protective measures. This feature is obvious

when examining the mean occupancy figure, which is

2.0 for amphibians and 1.8 for reptiles, indicating that

on average both groups occupy two or slightly fewer

physiographic provinces. The three most broadly dis-

tributed species (i.e., occurring in all five provinces) all

are reptiles and include the anole Anolis nebulosus , the

whipsnake Masticophis mentovarius, and the mud tur-

tle Kinosternon integrum (Table 4). The most broadly

distributed amphibians all are anurans and include the

following seven species: the toad Rhinella marina , the

chirping frog Eleutherodactylus nitidus, the treefrogs

Exerodonta smaragdina and Hyla arenicolor, the white-

lipped frog Leptodactylus fra gilis, the sheep frog Hypo-

pachus variolosus, and the leopard frog Lithobates neo-

volcanicus (Table 4).

Similar numbers of species have been recorded from

the Balsas-Tepalcatepec Depression, the Sierra Madre

del Sur, and the Transverse Volcanic Axis. A small-

er number occupies the Coastal Plain and the smallest

number is found on the Central Plateau. The distinction

between the species numbers in the higher-species areas

(Balsas-Tepalcatepec Depression, Sierra Madre del Sur,

and the Transvese Volcanic Axis) and the lower-species

areas (Coastal Plain and Central Plateau) is more marked

for amphibians than for reptiles (Table 5).

Table 4. Distribution of the native and non-native amphibian and reptiles of Michoacan, Mexico, by physiographic province.

Taxa

Physiographic Provinces

Coastal

Plain

(COP)

Balsas-

Tepalcatepec

Depression

(BTD)

SierraMadre

del Sur

(SMS)

Transverse

Volcanic Axis

(TVA)

Central

Plateau

(CEP)

Amphibia (54 species)

Anura (44 species)

Bufonidae (6 species)

Anaxyrus compactilis

+

Incilius marmoreus

+

Incilius occidentalis

+

Incilius perplexus

+

Incilius pisinnus

+

Rhinella marina

+

Craugastoridae (5 species)

Craugastor augusti

+

Craugastor hobartsmithi

+

Craugastor occidentalis

+

Craugastor pygmaeus

+

Craugastor vocalis

+

Eleutherodactylidae (5 species)

Eleutherodactylus angustidigitorum

+

Eleutherodactylus maurus

+

Eleutherodactylus modestus

+

Eleutherodactylus nitidus

+

Eleutherodactylus rufescens

+

Hylidae (11 species)

Agalychnis dacnicolor

+

Diaglena spatulata

+

Exerodonta smaragdina

+

Hyla arenicolor

+

Hyla eximia

+

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Physiographic distribution and conservation of Michoacan herpetofauna

Hyla plicata

+

Plectrohyla bistincta

+

Smilisca baudinii

+

Smilisca fodiens

+

Tlalocohyla smithii

+

Trachycephalus typhonius

+

Leptodactylidae (2 species)

Leptodactylus fragilis

+

Leptodactylus melanonotus

+

Microhylidae (2 species)

Hypopachus ustus

+

Hypopachus variolosus

+

Ranidae (11 species)

Lithobates berlandieri

+

Lit ho bates catesbeianus

+

Lithobates dunni

+

Lithobates forreri

+

Lithobates magnaocularis

+

Lithobates megapoda

+

Lithobates montezumae

+

Lithobates neovolcanicus

+

Lithobates pustulosus

+

Lithobates spectabilis

+

Lithobates zweifeli

+

Rhinophrynidae (1 species)

Rhinophrynus dorsalis

+

Scaphiopodidae (1 species)

Spea multiplicata

+

Caudata (9 species)

Ambystomatidae (6 species)

Ambystoma amblycephalum

+

Ambystoma andersoni

+

Ambystoma dumerilii

+

Ambystoma ordinarium

+

Ambystoma rivulare

+

Ambystoma velasci

+

Plethodontidae (3 species)

Pseudoeurycea bellii

+

Pseudoeurycea leprosa

+

Pseudoeurycea longicauda

+

Gymnophiona (1 species)

Caeciliidae (1 species)

Dermophis oaxacae

+

Reptilia (161 species)

Crocodylia (1 species)

Crocodylidae (1 species)

Crocodylus acutus

+

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Alvarado-Dfaz et al.

Squamata (153 species)

Bipedidae (1 species)

Bipes canaliculatus

+

Anguidae (6 species)

Abronia deppii

+

Barisia imbricata

+

Barisia jonesi

+

Barisia rudicollis

+

Elgaria kingii

+

Gerrhonotus liocephalus

+

Corytophanidae (1 species)

Basiliscus vittatus

+

Dactyloidae (2 species)

Anolis dunni

+

Anolis nebulosus

+

Eublepharidae (1 species)

Coieonyx eiegans

+

Gekkonidae (1 species)

Hemidactylus frenatus

+

Helodermatidae (1 species)

Heloderma horridum

+

Iguanidae (3 species)

Ctenosaura clarki

+

Ctenosaura pectinata

+

Iguana iguana

+

Mabuyidae (1 species)

Marisora brachypoda

+

Phrynosomatidae (20 species)

Phrynosoma asio

+

Phrynosoma orbiculare

+

Sceloporus aeneus

+

Sceloporus asper

+

Sceloporus bulled

+

Sceloporus dugesii

+

Sceloporus gadoviae

+

Sceloporus grammicus

+

Sceloporus heterolepis

+

Sceloporus horridus

+

Sceloporus insignis

+

Sceloporus melanorhinus

+

Sceloporus pyrocephalus

+

Sceloporus scalaris

+

Sceloporus siniferus

+

Sceloporus spinosus

+

Sceloporus torquatus

+

Sceloporus utiformis

+

Urosaurus bicarinatus

+

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Physiographic distribution and conservation of Michoacan herpetofauna

Urosaurus gadovi

+

Phyllodactylidae (5 species)

Phyllodactylus davisi

+

Phyllodactylus duellmani

+

Phyllodactylus homolepidurus

+

Phyllodactylus lane i

+

Phyllodactylus paucituberculatus

+

Scincidae (6 species)

Mesoscincus altamirani

+

Plestiodon colimensis

+

Plestiodon copei

+

Plestiodon dugesii

+

Plestiodon indubitus

+

Plestiodon parvulus

+

Sphenomorphidae (1 species)

Scincella assata

+

Teiidae (8 species)

Aspidoscelis calidipes

+

Aspidoscelis communis

+

Aspidoscelis costata

+

Aspidoscelis deppei

+

Aspidoscelis gularis

+

Aspidoscelis lineatissima

+

Aspidoscelis sacki

+

Holcosus undulatus

+

Xantusiidae (1 species)

Lepidophyma tarascae

+

Boidae (1 species)

Boa constrictor

+

Colubridae (28 species)

Conopsis biserialis

+

Conopsis lineatus

+

Conopsis nasus

+

Drymarchon melanurus

+

Drymobius margaritiferus

+

Geagras redimitus

+

Gyalopion canum

+

Lampropeltis ruthveni

+

Lampropeltis triangulum

+

Leptophis diplotropis

+

Masticophis flagellum

+

Masticophis mentovarius

+

Masticophis taeniatus

+

Mastigodryas melanolomus

+

Oxybelis aeneus

+

Pituophis deppei

+

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Alvarado-Dfaz et al.

Pituophis lineaticollis

+

Pseudoficimia frontalis

+

Salvadora bairdi

+

Salvadora mexicana

+

Senticolis triaspis

+

Sonora michoacanensis

+

Symphimus leucostomus

+

Tantilla bocourti

+

Tantilla calamarina

+

Tantilla cascadae

+

Trimorphodon biscutatus

+

Trimorphodon tau

+

Dipsadidae (33 species)

Coniophanes fissidens

+

Coniophanes lateritius

+

Coniophanes michoacanensis

+

Coniophanes piceivittis

+

Coniophanes sarae

+

Diadophis pu net at us

+

Dipsas gaigeae

+

Enuiius flavitorques

+

Enuiius oligostichus

+

Geophis bicolor

+

Geophis dugesii

+

Geophis incomptus

+

Geophis maculiferus

+

Geophis nigrocinctus

+

Geophis petersii

+

Geophis pyburni

+

Geophis sieboldi

+

Geophis tarascae

+

Hypsiglena torquata

+

Imantodes gemmistratus

+

Leptodeira maculata

+

Leptodeira nigrofasciata

+

Leptodeira septentrionalis

+

Leptodeira splendida

+

Leptodeira uribei

+

Pseudoleptodeira latifasciata

+

Rhadinaea hesperia

+

Rhadinaea laureata

+

Rhadinaea taeniata

+

Si bon nebulata

+

Tropidodipsas annulifera

+

Tropidodipsas fasciata

+

Tropidodipsas philippii

+

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Physiographic distribution and conservation of Michoacan herpetofauna

Elapidae (4 species)

Micrurus distans

+

Micrurus laticollaris

+

Micrurus tener

+

Pelamis platura

+

Leptotyphlopidae (4 species)

Epictia goudotii

+

Rena bressoni

+

Rena humilis

+

Rena maxima

+

Loxocemidae (1 species)

Loxocemus bicolor

+

Natricidae (11 species)

Adelophis copei

+

Storeria storerioides

+

Thamnophis cyrtopsis

+

Thamnophis eques

+

Thamnophis melanogaster

+

Thamnophis postremus

+

Thamnophis proximus

+

Thamnophis pulchrilatus

+

Thamnophis scalaris

+

Thamnophis scaliger

+

Thamnophis validus

+

Typhlopidae (1 species)

Ramphotyphlops braminus

+

Viperidae (10 species)

Agkistrodon bilineatus

+

Crotalus aquilus

+

Crotalus basiliscus

+

Crotalus culminatus

+

Crotalus molossus

+

Crotalus polystictus

+

Crotalus pusillus

+

Crotalus tancitarensis

+

Crotalus triseriatus

+

Porthidium hespere

+

Xenodontidae (2 species)

Conophis vittatus

+

Manolepis putnami

+

Testudines (7 species)

Cheloniidae (2 species)

Chelonia mydas

+

Lepidochelys olivacea

+

Dermochelyidae (1 species)

Dermochelys coriacea

+

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Alvarado-Dfaz et al.

Geoemydidae (2 species)

Rhinoclemmys pulcherrima

+

Rhinoclemmys rubida

+

Kinosternidae (2 species)

Kinosternon hirtipes

+

Kinosternon integrum

+

Table 5. Summary of the distributional occurrence of families of amphibians and reptiles in Michoacan by physiographic province.

Families

Number

of

Species

Distributional Occurrence

Coastal

Plain

(COP)

Balsas-

Tepalcatepec

Depression

(BTD)

Sierra Madre

del Sur

(SMS)

Transverse

Volcanic Axis

(TVA)

Central

Plateau

(CEP)

Bufonidae

6

2

4

5

2

Craugastoridae

5

—

2

3

5

—

Eleutherodactylidae

5

—

2

3

2

1

Hylidae

11

5

7

6

5

4

Leptodactylidae

2

1

—

Microhylidae

2

1

Ranidae

11

—

6

4

7

3

Rhinophrynidae

1

—

1

—

Scaphiopodidae

1

—

1

Subtotals

44

10

25

24

12

Ambystomatidae

6

—

6

—

Plethodontidae

3

—

3

—

Subtotals

9

—

9

—

Caeciliidae

1

—

1

—

Subtotals

1

—

1

—

Totals

54

11

25

24

34

12

Crocodylidae

1

—

Subtotals

1

—

Cheloniidae

2

—

Dermochelyidae

1

—

Geoemydidae

2

1

—

Kinosternidae

2

1

2

Subtotals

7

6

2

Bipedidae

1

—

1

—

Anguidae

6

—

2

4

—

Corytophanidae

1

—

Dactyloidae

2

1

2

1

Eublepharidae

1

—

Gekkonidae

1

—

Helodermatidae

1

—

Iguanidae

3

2

3

2

—

Mabuyidae

1

—

Phrynosomatidae

20

6

9

13

12

4

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Physiographic distribution and conservation of Michoacan herpetofauna

Phyllodactylidae

5

3

2

1

—

Scincidae

6

2

1

3

—

Sphenomorphidae

1

—

Teiidae

8

4

7

6

1

Xantusiidae

1

—

Subtotals

58

25

33

34

22

6

Boidae

1

—

Colubridae

28

11

13

15

6

Dipsadidae

33

8

10

19

9

—

Elapidae

4

1

2

1

—

Leptotyphlopidae

4

—

4

1

—

Loxocemidae

1

—

1

—

Natricidae

11

2

1

2

7

3

Typhlopidae

1

—

1

—

Viperidae

10

3

6

—

Xenodontidae

2

1

—

Subtotals

95

28

38

43

39

9

Totals

161

60

73

79

63

17

Sum Totals

215

71

98

103

97

29

Anurans are more broadly represented in the Balsas-Tepalcatepec Depression, where 25 species classified in all but

one of the nine families occurring in the state are found. These anurans are represented most narrowly on the Coastal

Plectrohyla bistincta. The Mexican fringe-limbed treefrog is

distributed from Durango and Veracruz southward to Mexico

and Oaxaca. Its EVS has been assessed as 9, placing at the

upper end of the low vulnerability category, this species

is considered as Least Concern by IUCN, and as a Special

Protection species by SEMARNAT. This individual came from

San Jose de las Tomes, near Morelia, in Michoacan.

Photo by Javier Alvarado -Diaz.

Plain, where only 10 species assigned to four families

occur. One or more species in the families Bufonidae,

Hylidae, and Microhylidae are distributed in each of the

five provinces (Table 5). As expected, the family Hylidae

is best represented in each of the provinces except for

the Transverse Volcanic Axis, where more ranids (sev-

en species) than hylids (five) occur. All nine species of

salamanders are limited in occurrence to the Transverse

Volcanic Axis and the single caecilian to the Transverse

Volcanic Axis and the Coastal Plain (Table 5).

Lizards are best represented in the Sierra Madre del

Sur, with 34 species, but the Balsas-Tepalcatepec De-

pression falls only one behind, with 33 (Table 5). Both

of these figures comprise more than one-half of the 58

species of lizards known from the state. Fewer than one-

half of this number occurs on the Coastal Plain (25) and

the Transverse Volcanic Axis (22). Only a few species

(six) occur on the Central Plateau. In the families Dacty-

loidae, Phrynosomatidae, and Teiidae, one or more spe-

cies is distributed in each of the five provinces (Table 5).

Due to the size of the Phrynosomatidae in Michoacan

(20 species), this family is the best represented in each

of the provinces. Several lizard families are represented

by a single species in each of the provinces, but only

one with a single species (the Bipedidae) is limited to a

single province (Table 5).

The largest number of snake species is known from

the Sierra Madre del Sur, with 43 species. Fewer num-

bers are found in the Transverse Volcanic Axis (39), Bal-

sas-Tepalcatepec Depression (38), Coastal Plain (28),

and the Central Plateau (nine). One or more represen-

tatives of only two snake families, the Colubridae and

Natricidae, are found in each of the five provinces (Table

5). Interestingly, although the Colubridae in Michoacan

is represented by five fewer species than the Dipsadidae,

it is the best-represented family in all of the provinces

except for the Sierra Madre del Sur, in which the Dip-

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144

Alvarado-Dfaz et al.

Amby stoma velasci. The plateau tiger salamander is found along the Transverse Volcanic Axis in Michoacan and elsewhere, thence

northward into both the Sierra Madre Occidental to northwestern Chihuahua and the Sierra Madre Oriental to southern Nuevo

Leon. Its EVS has been assigned a value of 10, placing it at the lower end of the medium vulnerability category, its status has been

judged as Least Concern by IUCN, and it is considered a Special Protection species by SEMARNAT. This individual came from

Los Azufres, in the Tranverse Volcanic Axis. Photo by Javier Alvarado-Dfaz.

sadidae is the best represented. Only three snake fam-

ilies are represented by a single species (including the

Typhlopidae, containing the non-native blindsnake Ram-

photyphlops braminus ), but in all three cases they occur

in two or three provinces (Table 5).

Relatively few species of turtles have been recorded

in Michoacan, and given that three of the seven are sea

turtles, most of them (six) are known from the Coastal

Plain (obviously, sea turtles come on land for egg depo-

sition). Only two species of the families Geoemydidae

and/or Kinosternidae are found in the remaining four

provinces (Table 5). The single crocodylian species is

found only in the Coastal Plain (Table 5).

We constructed a Coefficient of Biogeographic Re-

semblance (CBR) matrix to examine the herpetofaunal

relationships among the five physiographic provinces

(Table 6). The data in this table demonstrate that the

greatest degree of resemblance (74 species shared, CBR

value of 0.74) occurs between the Balsas-Tepalcate-

pec Depression and the Sierra Madre del Sur (Table 6).

Whereas this fact might be considered counterintuitive,

given the elevational distinction between the two areas,

these two provinces broadly contact one another along

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the northern and eastern face of the mountain mass (Fig.

1). A greater degree of resemblance might be expected

between the Balsas-Tepalcatepec Depression and the

Coastal Plain, inasmuch as these are relatively low-el-

evation areas, but they only contact one another where

the Rfo Balsas flows onto the coastal plain prior to en-

tering the Pacific Ocean. As a consequence, these two

provinces share only 44 species and their CBR value is

0.52 (Table 6). Nonetheless, these values are the highest

that the Coastal Plain shares with any of the other four

provinces, with the exception of the Sierra Madre del Sur

(44 species and 0.51). For a similar reason, it might be

expected that the Balsas-Tepalcatepec Depression would

share a relatively large number of species with the Trans-

verse Volcanic Axis to the north, but this is not the case.

Only 21 species are shared and the CBR value is only

0.22 (Table 6).

One might also presume that the Transverse Volcanic

Axis and the Sierra Madre del Sur would share a siz-

able number of montane-distributed species, but the two

provinces only share 29 species and their CBR value is

0.29. The Central Plateau is adjacent to the Transverse

Volcanic Axis and the data in Table 6 demonstrate that

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Physiographic distribution and conservation of Michoacan herpetofauna

Table 6. CBR matrix of herpetofaunal relationships for the five physiographic provinces in Michoacan. N = species in each

province; N = species in common between two provinces; N = Coefficients of Biogeographic Resemblance. The formula for this

algorithm is CBR = 2C/N1 + N2, where C is the number of species in common to both provinces, N1 is the number of species in

the first province, and N2 is the number of species in the second province.

COP

BTD

SMS

TVA

CEP

COP

71

44

9

4

BTD

0.52

98

74

21

11

SMS

0.51

0.74

103

29

9

TVA

0.11

0.22

0.29

97

26

CEP

0.08

0.17

0.14

0.41

29

26 of the 29 species found in the Central Plateau also are

recorded from the Transverse Volcanic Axis, but because

of the disparity in the size of their respective herpeto-

faunas their CBR value is only 0.41. Nonetheless, this

is the Central Plateau’s greatest degree of resemblance

with any of the other four provinces.

As opposed to species shared between or among

physiographic provinces, the distribution of some spe-

cies is confined to a single province (Table 4), although

sometimes these are more broadly distributed outside the

state. In the Coastal Plain, the following 22 species are

involved:

Trachycephalus typhonius

Hypopachus ustus

Crocodylus acutus

Phyllodactylus davisi

Phyllodactylus homolepidurus

Plestiodon parvulus

Geagras redimitus

Symphimus leucostomus

Coniophanes michoacanensis

Coniophanes piceivittis

Enulius oligostichus

Leptodeira nigrofasciata

Leptodeira uribei

Pelamis platura

Thamnophis proximus

Thamnophis validus

Porthidium hespere

Plestiodon parvulus

Chelonia mydas

Lepidochelys olivacea

Dermochelys coriacea

Rhinoclemmys pulcherrima

In the Balsas-Tepalcatepec Depression, the follow-

ing 16 species are confined to this province:

Eleutherodactylus maurus

Lithobates berlandieri

Lithobates magnaocularis

Rhinophrynus dorsalis

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Bipes canaliculatus

Ctenosaura clarki

Phyllodactylus paucituberculatus

Aspidoscelis sacki

lmantodes gemmistratus

Leptodeira septentrionalis

Micrurus laticollaris

Rena bressoni

Rena humilis

Rena maxima

Thamnophis postremus

Crotalus culminatus

The following 14 species are limited to the Sierra

Madre del Sur, within the state:

Eleutherodactylus modestus

Eleutherodactylus rufescens

Barisia jonesi

Elgaria kingii

Sceloporus bulleri

Sceloporus insignis

Coniophanes sarae

Dipsas gaigeae

Geophis incomptus

Geophis nigrocinctus

Geophis pyburni

Geophis sieboldi

Tropidodipsas annulifera

Tropidodipsas fas data

The herpetofauna of the Transverse Volcanic Axis in

Michoacan contains the following 47 single-province

species (. Lithobates catesbeianus, a non-native species,

is not listed):

Craugastor hobartsmithi

Craugastor occidental is

Eleutherodactylus angustidigitorum

Hyla plicata

Lithobates dunni

Lithobates spectabilis

Ambystoma amblycephalum

Amby stoma andersoni

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Ambystoma dumerilii

Ambystoma ordinarium

Ambystoma rivulare

Ambystoma velasci

Pseudoeurycea bellii

Pseudoeurycea leprosa

Pseudoeurycea longicauda

Abronia deppii

Barisia imbricata

Barisia rudicollis

Gerrhonotus liocephalus

Phrynosoma orbiculare

Sceloporus aeneus

Sceloporus grammicus

Plestiodon copei

Plestiodon dugesii

Conopsis biserialis

Conopsis nasus

Gyalopion canum

Lampropeltis ruthveni

Lampropeltis triangulum

Tantilla bocourti

Tantilla cascadae

Diadophis punctatus

Geophis bicolor

Geophis dugesii

Geophis maculiferus

Geophis tarascae

Rhadinaea laureata

Rhadinaea taeniata

Micrurus tener

Thamnophis melanogaster

Thamnophis pulchrilatus

Thamnophis scalaris

Crotalus aquilus

Crotalus molossus

Crotalus polystictus

Crotalus tancitarensis

Crotalus triseriatus

Finally, the Central Plateau herpetofauna includes

only one species limited to this province, as follows:

Adelophis copei

In total, of the 212 native species, 100 (47.2%) are

confined to a single physiographic province within the

state. Organizing these single-province species by their

distributional status (Table 7) indicates the following

(listed in order of state endemics, country endemics, and

non-endemic species): Coastal plain (22 total species)

= 1 (4.5%), 10 (45.5%), 11 (50.0%); Balsas-Tepalcate-

Pseudoeurycea bellii. Bell’s false brook salamander occurs from southern Tamaulipas and southern Nayarit southward to Tlaxcala

and Guerrero, Mexico, with a disjunct population found in east-central Sonora and adjacent Chihuahua. Its EVS has been gauged

as 12, placing it in the upper portion of the medium vulnerability category, its status has been judged as Vulnerable by IUCN, and it

is regarded as Threatened by SEMARNAT. This individual was found and photographed on Cerro Tancitaro, Michoacan.

Photo by Javier Alvarado-Diaz.

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pec Depression (16 species) = 3 (18.8%), 7 (43.8%), 6

(37.4%); Sierra Madre del Sur (14 species) = 5 (35.7%), 8

(57.2%), 1 (7.1%); Transverse Volcanic Axis = 8 (17.0%),

32 (68.1%), 7 (14.9%); Central Plateau = 0 (0.0%), 1

(100%), 0 (0.0%). Most of these single-province species

are country-level endemics (58 [58.0%]); and the remain-

ing are non-endemics (25 [25.0%]) or state-level endem-

ics (17 [17.0%]).

Conservation Status

We employed three systems in creating a comprehensive

view of the conservation status of the amphibians and rep-

tiles of Michoacan (see Materials and Methods), of which

one was developed for use in Mexico (the SEMARNAT

system), another developed for use in Central America

(the EVS system, Wilson and Johnson 2010) and later

applied to Mexico (Wilson et al. 2013a,b), and a third

developed for use on a global basis (the IUCN system).

We discuss the application of these systems to the herpe-

tofauna of Michoacan below.

Table 7. Distributional and conservation status measures for members of the herpetofauna of Michoacan, Mexico. Distributional

Status: SE = endemic to state of Michoacan; CE = endemic to country of Mexico; NE = not endemic to state or country; NN

= non-native. Environmental Vulnerability Score (taken from Wilson et al. 2013a, b): low vulnerability species (EVS of 3-9);

medium vulnerability species (EVS of 10-13); high vulnerability species (EVS of 14-20). IUCN Categorization: CR = Critically

Endangered; EN = Endangered; VU = Vulnerable; NT = Near Threatened; LC = Least Concern; DD = Data Deficient; NE =

Not Evaluated. SEMARNAT Status: A = Threatened; P = Endangered; Pr = Special Protection; NS = No Status. See text for

explanations of the EVS, IUCN, and SEMARNAT rating systems.

Taxa

Distributional

Status

Environmental

Vulnerability

Score

IUCN

Categorization

SEMARNAT

Status

Amphibia (54 species)

Anura (44 species)

Bufonidae (6 species)

Anaxyrus compactilis

CE

14

LC

NS

Incilius marmoreus

CE

11

LC

NS

Incilius occidentalis

CE

11

LC

NS

Incilius perplexus

CE

11

EN

NS

Incilius pisinnus

SE

15

DD

NS

Rhinella marina

NE

3

LC

NS

Craugastoridae (5 species)

Craugastor augusti

NE

8

LC

NS

Craugastor hobartsmithi

CE

15

EN

NS

Craugastor occidentalis

CE

13

DD

NS

Craugastor pygmaeus

NE

9

VU

NS

Craugastor vocalis

CE

13

LC

NS

Eleutherodactylidae (5 species)

Eleutherodactylus angustidigitorum

SE

17

VU

Pr

Eleutherodactylus maurus

CE

17

DD

Pr

Eleutherodactylus modestus

CE

16

VU

Pr

Eleutherodactylus nitidus

CE

12

LC

NS

Eleutherodactylus rufescens

SE

17

CR

Pr

Hylidae (11 species)

Agalychnis dacnicolor

CE

13

LC

NS

Diaglena spatulata

CE

13

LC

NS

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Exerodonta smaragdina

CE

12

LC

Pr

Hyla arenicolor

NE

7

LC

NS

Hyla eximia

NE

10

LC

NS

Hyla plicata

CE

11

LC

A

Plectrohyla bistincta

CE

9

LC

Pr

Smilisca baudinii

NE

3

LC

NS

Smilisca fodiens

NE

8

LC

NS

Tlalocohyla smithii

CE

11

LC

NS

Trachycephalus typhonius

NE

4

LC

NS

Leptodactylidae (2 species)

Leptodactylus fragilis

NE

5

LC

NS

Leptodactylus melanonotus

NE

6

LC

NS

Microhylidae (2 species)

Hypopachus ustus

NE

7

LC

Pr

Hypopachus variolosus

NE

4

LC

NS

Ranidae (11 species)

Lithobates berlandieri

NE

7

LC

Pr

Lithobates catesbeianus

NN

—

Lithobates dunni

SE

14

EN

Pr

Lithobates forreri

NE

3

LC

Pr

Lithobates magnaocularis

CE

12

LC

NS

Lithobates megapoda

CE

14

VU

Pr

Lithobates montezumae

CE

13

LC

Pr

Lithobates neovolcanicus

CE

13

NT

A

Lithobates pustulosus

CE

9

LC

Pr

Lithobates spectabilis

CE

12

LC

NS

Lithobates zweifeli

CE

11

LC

NS

Rhinophrynidae (1 species)

Rhinophrynus dorsalis

NE

8

LC

Pr

Scaphiopodidae (1 species)

Spea multiplicata

NE

6

LC

NS

Caudata (9 species)

Ambystomatidae (6 species)

Ambystoma amblycephalum

SE

13

CR

Pr

Ambystoma andersoni

SE

15

CR

Pr

Ambystoma dumerilii

SE

15

CR

Pr

Ambystoma ordinarium

CE

13

EN

Pr

Ambystoma rivulare

CE

13

DD

A

Ambystoma velasci

CE

10

LC

Pr

Plethodontidae (3 species)

Pseudoeurycea bellii

CE

12

VU

A

Pseudoeurycea leprosa

CE

16

VU

A

Pseudoeurycea longicauda

CE

17

EN

Pr

Gymnophiona (1 species)

Caeciliidae (1 species)

Dermophis oaxacae

CE

12

DD

Pr

Reptilia (161 species)

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Crocodylia (1 species)

Crocodylidae (1 species)

Crocodylus acutus

NE

14

VU

Pr

Squamata (153 species)

Bipedidae (1 species)

Bipes canaliculatus

CE

12

LC

Pr

Anguidae (6 species)

Abronia deppii

CE

16

EN

A

Barisia imbricata

CE

14

LC

Pr

Barisia jonesi

SE

16

NE

NS

Barisia rudicollis

CE

15

EN

P

Elgaria kingii

NE

10

LC

Pr

Gerrhonotus liocephalus

NE

6

LC

Pr

Corytophanidae (1 species)

Basiliscus vittatus

NE

7

NE

NS

Dactyloidae (2 species)

Anolis dunni

CE

16

LC

A

Anolis nebulosus

CE

13

LC

NS

Eublepharidae (1 species)

Coieonyx eiegans

NE

9

NE

A

Gekkonidae (1 species)

Hemidactylus frenatus

NN

—

Helodermatidae (1 species)

Heloderma horridum

NE

11

LC

A

Iguanidae (3 species)

Ctenosaura clarki

CE

15

VU

A

Ctenosaura pectinata

CE

15

NE

A

Iguana iguana

NE

12

NE

Pr

Mabuyidae (1 species)

Marisora brachypoda

NE

6

NE

NS

Phrynosomatidae (20 species)

Phrynosoma asio

NE

11

NE

Pr

Phrynosoma orbiculare

CE

12

LC

A

Sceloporus aeneus

CE

13

LC

NS

Sceloporus asper

CE

14

LC

Pr

Sceloporus bulled

CE

15

LC

NS

Sceloporus dugesii

CE

13

LC

NS

Sceloporus gadoviae

CE

11

LC

NS

Sceloporus grammicus

NE

9

LC

Pr

Sceloporus heterolepis

CE

14

LC

NS

Sceloporus horridus

CE

11

LC

NS

Sceloporus insignis

CE

16

LC

Pr

Sceloporus melanorhinus

NE

9

LC

NS

Sceloporus pyrocephalus

CE

12

LC

NS

Sceloporus scalaris

NE

12

LC

NS

Sceloporus siniferus

NE

11

LC

NS

Sceloporus spinosus

CE

12

LC

NS

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Sceloporus torquatus

CE

11

LC

NS

Sceloporus utiformis

CE

15

LC

NS

Urosaurus bicarinatus

CE

12

LC

NS

Urosaurus gadovi

CE

12

LC

NS

Phyllodactylidae (5 species)

Phyllodactylus davisi

CE

16

LC

A

Phyllodactylus duellmani

SE

16

LC

Pr

Phyllodactylus homolepidurus

CE

15

LC

Pr

Phyllodactylus lanei

CE

15

LC

NS

Phyllodactylus paucituberculatus

SE

16

DD

A

Scincidae (6 species)

Mesoscincus altamirani

CE

14

DD

Pr

Plestiodon colimensis

CE

14

DD

Pr

Plestiodon copei

CE

14

LC

Pr

Plestiodon dugesii

CE

16

VU

Pr

Plestiodon indubitus

CE

15

LC

NS

Plestiodon parvulus

CE

15

DD

NS

Sphenomorphidae (1 species)

Sphenomorphus assatus

NE

7

NE

NS

Teiidae (8 species)

Aspidoscelis calidipes

SE

14

LC

Pr

Aspidoscelis communis

CE

14

LC

Pr

Aspidoscelis costata

CE

11

LC

Pr

Aspidoscelis deppei

NE

8

LC

NS

Aspidoscelis gularis

NE

9

LC

NS

Aspidoscelis lineatissima

CE

14

LC

Pr

Aspidoscelis sacki

CE

14

LC

NS

Holcosus undulatus

NE

7

NE

NS

Xantusiidae (1 species)

Lepidophyma tarascae

CE

14

DD

A

Boidae (1 species)

Boa constrictor

NE

10

NE

A

Colubridae (28 species)

Conopsis biserialis

CE

13

LC

A

Conopsis lineata

CE

13

LC

NS

Conopsis nasus

CE

11

LC

NS

Drymarchon melanurus

NE

6

LC

NS

Drymobius margaritiferus

NE

6

NE

NS

Geagras redimitus

CE

14

DD

Pr

Gyalopion canum

NE

9

LC

NS

Lampropeltis ruthveni

CE

16

NT

A

Lampropeltis triangulum

NE

7

NE

A

Leptophis diplotropis

CE

14

LC

A

Masticophis flagellum

NE

8

LC

A

Masticophis mentovarius

NE

6

NE

A

Masticophis taeniatus

NE

10

LC

NS

Mastigodryas melanolomus

NE

6

LC

NS

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Oxybelis aeneus

NE

5

NE

NS

Pituophis deppei

CE

14

LC

A

Pituophis lineaticollis

NE

8

LC

NS

Pseudoficimia frontalis

CE

13

LC

Pr

Salvador a bairdi

CE

15

LC

Pr

Salvador a mexicana

CE

15

LC

Pr

Senticolis triaspis

NE

6

NE

NS

Sonora michoacanensis

CE

14

LC

NS

Symphimus leucostomus

CE

14

LC

Pr

Tantilla bocourti

CE

9

LC

NS

Tantilla calamarina

CE

12

LC

Pr

Tantilla cascadae

SE

16

DD

A

Trimorphodon biscutatus

NE

7

NE

NS

Trimorphodon tau

CE

13

LC

NS

Dipsadidae (33 species)

Coniophanes fissidens

NE

7

NE

NS

Coniophanes lateritius

CE

13

DD

NS

Coniophanes michoacanensis

SE

17

NE

NS

Coniophanes piceivittis

NE

7

LC

NS

Coniophanes sarae

SE

16

DD

NS

Di ado phis punctatus

NE

4

LC

NS

Dipsas gaigeae

CE

17

LC

Pr

Enulius flavi torques

NE

5

NE

NS

Enulius oligostichus

CE

15

DD

Pr

Geophis bicolor

CE

15

DD

Pr

Geophis dugesii

CE

13

LC

NS

Geophis incomptus

SE

16

DD

Pr

Geophis maculiferus

SE

16

DD

Pr

Geophis nigrocinctus

CE

15

DD

Pr

Geophis petersii

CE

15

DD

Pr

Geophis pyburni

SE

16

DD

Pr

Geophis sieboldi

CE

13

DD

Pr

Geophis tarascae

CE

15

DD

Pr

Hypsiglena torquata

NE

8

LC

Pr

Imantodes gemmistratus

NE

6

NE

Pr

Leptodeira maculata

CE

7

LC

Pr

Leptodeira nigrofasciata

NE

8

LC

NS

Leptodeira septentrionalis

NE

8

NE

NS

Leptodeira splendida

CE

14

LC

NS

Leptodeira uribei

CE

17

LC

Pr

Pseudoleptodeira latifasciata

CE

14

LC

Pr

Rhadinaea hesperia

CE

10

LC

Pr

Rhadinaea laureata

CE

12

LC

NS

Rhadinaea taeniata

CE

13

LC

NS

Sibon nebulatus

NE

5

NE

NS

Tropidodipsas annulifera

CE

13

LC

Pr

Tropidodipsas fasciata

CE

13

NE

NS

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Tropidodipsas philippii

CE

14

LC

Pr

Elapidae (4 species)

Micrurus distans

CE

14

LC

Pr

Micrurus laticollaris

CE

14

LC

Pr

Micrurus tener

NE

11

LC

NS

Pelamis platura

NE

—

LC

NS

Leptotyphlopidae (4 species)

Epictia goudotii

NE

3

NE

NS

Rena bressoni

SE

14

DD

Pr

Rena humilis

NE

8

LC

NS

Rena maxima

CE

11

LC

NS

Loxocemidae (1 species)

Loxocemus bicolor

NE

10

NE

Pr

Natricidae (11 species)

Adelophis copei

CE

15

VU

Pr

Storeria storerioides

CE

11

LC

NS

Thamnophis cyrtopsis

NE

7

LC

A

Thamnophis eques

NE

8

LC

A

Thamnophis melanogaster

CE

15

EN

A

Thamnophis postremus

SE

15

LC

NS

Thamnophis proximus

NE

7

NE

NS

Thamnophis pulchrilatus

CE

15

LC

NS

Thamnophis scalaris

CE

14

LC

A

Thamnophis scaliger

CE

15

VU

A

Thamnophis validus

CE

12

LC

NS

Typhlopidae (1 species)

Ramphotyphlops braminus

NN

—

Viperidae (10 species)

Agkistrodon bilineatus

NE

11

NT

Pr

Crotalus aquilus

CE

16

LC

Pr

Crotalus basiliscus

CE

16

LC

Pr

Crotalus culminatus

CE

15

NE

NS

Crotalus molossus

NE

8

LC

Pr

Crotalus polystictus

CE

16

LC

Pr

Crotalus pusillus

CE

18

EN

A

Crotalus tancitarensis

SE

19

DD

NS

Crotalus triseriatus

CE

16

LC

NS

Porthidium hespere

CE

18

DD

Pr

Xenodontidae (2 species)

Conophis vittatus

CE

11

LC

NS

Manolepis putnami

CE

13

LC

NS

Testudines (7 species)

Cheloniidae (2 species)

Chelonia mydas

NE

—

EN

P

Lepidochelys olivacea

NE

—

VU

P

Dermochelyidae (1 species)

Dermochelys coriacea

NE

—

CR

P

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Geoemydidae (2 species)

Rhinodemmys pulcherrima

NE

8

NE

A

Rhinodemmys rubida

CE

14

NT

Pr

Kinosternidae (2 species)

Kinosternon hirtipes

NE

10

LC

Pr

Kinosternon integrum

CE

11

LC

Pr

Pseudoeurycea leprosa. The leprous false brook salamander occurs in Veracruz, Puebla, Distrito Federal, Mexico, Morelos,

Guerrero, and Oaxaca. Its EVS has been judged as 16, placing it in the middle of the high vulnerability category, IUCN has assessed

this species as Vulnerable, and it is considered as Threatened by SEMARNAT. This individual was encountered on Cerro Cacique,

near Zitacuaro, in Michoacan. Photo by Oscar Medina- Aguilar.

Abronia deppii. Deppe’s arboreal alligator lizard is found in the mountains of the Transverse Volcanic Axis in Michoacan, Mexico,

and Jalisco. Its EVS has been judged as 16, placing it in the middle of the high vulnerability category, IUCN considers this species

as Endangered, and it has been provided a Threatened status by SEMARNAT. This individual came from San Jose de las Torres,

near Morelia, in Michoacan. Photo by Javier Alvarado-Dfaz.

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Barisia imbricata. In Michoacan, the imbricate alligator lizard occurs in the Transverse Volcanic Axis. The systematics of this

species, however, is currently in flux, and based on indications in recent molecular work this taxon likely will be divided into a

number of species. Its EVS has been estimated as 14, placing it at the lower end of the high vulnerability category, this species has

been judged as Least Concern by IUCN, and given a Special Protected status by SEMARNAT. This individual is from Tacambaro,

in the Transverse Volcanic Axis of Michoacan. Photo by Oscar Medina- Aguilar.

1. The SEMARNAT system

The application of the SEMARNAT system appears in

NOM-059-SEMARNAT-2010 (available at www.semar-

nat.gob.mx), and uses three categories: Endangered (P),

Threatened (A), and Special Protection (Pr). In addition

to these categories, we considered the species left untreat-

ed in the SEMARNAT system as having “No status.” We

listed the SEMARNAT categorizations in Table 7 and

summarized the results of the partitioning of the 212 na-

tive species in Table 8.

Perusal of the tabular data reveals one important con-

clusion — almost one-half of the species in Michoacan (98

[46.2%]) are not considered in the SEMARNAT system

(Table 8). The missing species include 27 anurans, 27 liz-

ards, and 44 snakes, and include the following: all six of

the bufonids, of which five are Mexican endemic species

(one is endemic to Michoacan); all five of the craugas-

torids, of which three are Mexican endemics; eight of

11 hylids, of which three are Mexican endemics; one of

two dactyloids, which one is a Mexican endemic; 15 of

20 phrynosomatids, of which 12 are Mexican endemics;

one-half of the 28 colubrids, of which five are Mexican

endemics; 15 of 33 dipsadids, of which eight are Mexican

endemics (two also are state endemics); four of 11 natri-

cids, of which four are Mexican endemics (one also is a

state endemic); and two of 10 viperids, of which two are

Mexican endemics (one also is a state endemic).

Of the 212 total species, only four (1.9%) are judged

as Endangered (three are sea turtles from the coastal wa-

ters of the state and one is the anguid Abronia deppii ).

Thirty-one species (14.6%) are considered as Threatened

and 79 (37.1%) as needing Special Protection (Table 8).

In the end, any system purporting to at least identify

species in need of conservation attention is better than no

system at all. The SEMARNAT system, however, is seri-

ously deficient because a high percentage of species are

not provided with a conservation status, and a significant

portion of these taxa are state or country level endemics.

We address our concerns in the Conclusions and Recom-

mendations section.

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Table 8. SEMARNAT categorizations for amphibians and reptiles in Michoacan arranged by families. Non-native species are

excluded.

Families

Number

of

Species

SEMARNAT Categorizations

Endangered (P)

Threatened (A)

Special

Protection (Pr)

No Status

Bufonidae

6

—

6

Craugastoridae

5

—

5

Eleutherodactylidae

5

—

4

1

Hylidae

11

—

1

2

8

Leptodactylidae

2

—

2

Microhylidae

2

—

1

Ranidae

10

—

1

6

3

Rhinophrynidae

1

—

1

—

Scaphiopodidae

1

—

1

Subtotals

43

—

2

14

27

Ambystomatidae

6

—

1

5

—

Plethodontidae

3

—

2

1

—

Subtotals

9

—

3

6

—

Caeciliidae

1

—

1

—

Subtotals

1

—

1

—

Totals

53

—

5

21

27

Crocodylidae

1

—

1

—

Subtotals

1

—

1

—

Cheloniidae

2

—

Dermochelyidae

1

—

Geoemydidae

2

—

1

—

Kinosternidae

2

—

2

—

Subtotals

7

3

1

3

—

Bipedidae

1

—

1

—

Anguidae

6

1

3

1

Corytophanidae

1

—

1

Dactyloidae

2

—

1

—

1

Eublepharidae

1

—

1

—

Helodermatidae

1

—

1

—

Iguanidae

3

—

2

1

—

Mabuyidae

1

—

1

Phrynosomatidae

20

—

1

4

15

Phyllodactylidae

5

—

2

1

Scincidae

6

—

4

2

Sphenomorphidae

1

—

1

Teiidae

8

—

4

Xantusiidae

1

—

1

—

Subtotals

57

1

10

19

27

Boidae

1

—

1

—

Colubridae

28

—

8

6

14

Dipsadidae

33

—

18

15

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Leptotyphlopidae

4

—

1

3

Loxocemidae

1

—

1

—

Natricidae

11

—

5

1

5

Viperidae

10

—

1

6

3

Xenodontidae

2

—

2

Subtotals

94

—

15

35

44

Totals

159

4

26

58

71

Sum Totals

212

4

31

79

98

2. The IUCN system

Coleonyx elegans. The elegant banded gecko is broadly distributed on both versants, from southern Nayarit and Veracruz in Mexico

southward to Guatemala and Belize. In Michoacan, it inhabits the Coastal Plain and Balsas-Tepalcatepec Depression physiographic

provinces. Its EVS has been indicated as 9, placing it at the upper end of the low vulnerability category, its IUCN status has not

been assessed, and this gecko is regarded as Threatened by SEMARNAT. This individual came from Colola, on the coast of

Michoacan. Photo by Javier Alvarado-Diaz.

Ctenosaura clarki. The Balsas armed lizard is endemic to the Balsas-Tepalcatepec Depression. Its EVS has been gauged as

15, placing it in the lower portion of the high vulnerability category, this species has been judged as Vulnerable by IUCN, and

considered as Threatened by SEMARNAT. This individual is from Nuevo Centro, Reserva de la Biosfera Infiernillo-Zicuiran, near

the Presa Infiernillo on the Rio Balsas in southeastern Michoacan. Photo by Javier Alvarado-Diaz.

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Physiographic distribution and conservation of Michoacan herpetofauna

The IUCN system is the most widely used system for cat-

egorizing the conservation status of the world’s organ-

isms, although it is skewed heavily toward chordate ani-

mals, as assessed by Stuart et al. (2010b). Of the 64,788

described chordate species, 27,882 (43.0%) had been as-

sessed on the IUCN Red List by the year 2009; compara-

tively, only 7,615 of 1,359,365 species of other described

animals had been assessed, a miniscule 0.56%. In fact,

if all of the 1,424,153 animal species treated in Stuart

et al. (2010b) are considered, only 2.5% have been as-

sessed on the IUCN Red List. This extant situation is not

so much of a criticism of the effectiveness of the IUCN

system, but rather a criticism of the lack of attention giv-

en to conservation of the world’s organisms by humanity

at large (Wilson 2002). As a case in point, Stuart et al.

(2010b) reported that if a provisional target number of

106,979 animal species (only 7.5% of the total number

of described species) were established in attempting to

develop a broader taxonomic base of threatened animal

species, the estimated cost to complete would be about

$36,000,000. Completion of a threatened species assess-

ment, however, is only the first step toward providing a

given species adequate protection for perpetuity.

We listed the current IUCN Red List categorizations

for the Michoacan herpetofauna in Table 7 and summa-

rized the results in Table 9. The allocations of the 212

species assessed to the seven IUCN categories are as fol-

lows: Critically Endangered (CR) = 5 species (2.3%); En-

dangered (E) = 10 (4.7%); Vulnerable (VU) = 12 (5.6%);

Near Threatened (NT) = 4 (1.9%); Least Concern (LC)

= 127 (60.0%); Data Deficient (DD) = 26 (12.3%); and

Not Evaluated (NE) = 28 (13.2%). These results are typ-

ical of those allocated for all Mexican amphibians and

reptiles (see Wilson et al. 2013a,b). As a consequence,

only 27 of the 213 species (12.7%) occupy the threatened

categories (CR, EN, or VU). Six of every 10 species are

judged at the lowest level of concern (LC). Finally, 54

species (25.5%) have been assessed either as DD or have

not been assessed (NE).

Table 9. IUCN Red List categorizations for amphibian and reptile families in Michoacan. Non-native species are excluded.

Families

Number

of

Species

IUCN Red List categorizations

Critically

Endangered

Vulnerable

Near

Threatened

Least

Concern

Data

Deficient

Not

Evaluated

Bufonidae

6

—

1

—

4

1

—

Craugastoridae

5

—

1

—

2

1

—

Eleutherodactylidae

5

1

—

2

—

1

—

Hylidae

11

—

11

—

Leptodactylidae

2

—

2

—

Microhylidae

2

—

2

—

Ranidae

10

—

1

7

—

Rhinophrynidae

1

—

1

—

Scaphiopodidae

1

—

1

—

Subtotals

43

1

3

4

1

31

3

—

Ambystomatidae

6

3

1

—

1

—

Plethodontidae

3

—

1

2

—

Subtotals

9

3

2

—

1

Caeciliidae

1

—

1

—

Subtotals

1

—

1

—

Totals

53

4

5

6

1

32

5

—

Crocodylidae

1

—

1

—

Subtotals

1

—

1

—

Cheloniidae

2

—

1

—

Dermochelyidae

1

—

Geoemydidae

2

—

1

—

1

Kinosternidae

2

—

2

—

Subtotals

7

1

2

—

1

Bipedidae

1

—

1

—

Anguidae

6

—

2

—

3

—

1

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Alvarado-Diaz et al.

Corytophanidae

1

Dactyloidae

2

—

2

—

Eublepharidae

1

—

1

Helodermatidae

1

—

1

—

Iguanidae

3

—

1

—

2

Mabuyidae

1

—

1

Phrynosomatidae

20

—

19

—

1

Phyllodactyiidae

5

—

4

1

—

Scincidae

6

—

1

—

2

3

—

Sphenomorphidae

1

—

1

Teiidae

8

—

7

—

1

Xantusiidae

1

—

1

—

Subtotals

57

—

2

—

39

5

9

Boidae

1

—

1

Colubridae

28

—

1

19

2

6

Dipsadidae

33

—

15

11

7

Elapidae

4

—

4

—

Leptotyphlopidae

4

—

2

1

Loxocemidae

1

—

1

Natricidae

11

—

1

2

—

7

—

1

Viperidae

10

—

1

—

1

5

2

1

Xenodontidae

2

—

2

—

Subtotals

94

—

2

54

16

19

Totals

151

1

5

6

3

96

21

28

Sum Totals

212

5

10

12

4

127

26

28

Phyllodactylus duellmani. Duellman’s pigmy leaf-toed gecko is endemic to Michoacan, where it is found in the Balsas-Tepalcatepec

Depression and the Sierra Madre del Sur. Its EVS has been assigned a value of 16, placing it in the middle of the high vulnerability

category, this species has been judged as Least Concern by IUCN, and accorded a Special Protection status by SEMARNAT. This

individual was photographed at Nuevo Centro, Reserva de la Biosfera Infiernillo-Zicuiran, near the Presa Infiernillo on the Rio

Balsas in southeastern Michoacan. Photo by Oscar Medina- Aguilar.

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Physiographic distribution and conservation of Michoacan herpetofauna

Leptodeira uribei. Uribe’s cat-eyed snake is distributed along the coastal plain in

Michoacan, and northward through the lowlands to Jalisco and southward to Oaxaca. Its

EVS has been gauged as 17, placing it in the middle of the high vulnerability category, its

IUCN status has been assessed as Least Concern, and it is considered a Special Protection

species by SEMARNAT. This individual was found at San Mateo, near the Reserva de la

Biosfera Chamela-Cuixmala on the coast of Jalisco. Photo by Javier Alvarado -Diaz.

Thamnophis postremus. The Michoacan gartersnake is a state endemic. Its EVS has been

allocated as 15, placing it in the lower portion of the high vulnerability category, it has

been judged as Least Concern by IUCN, and this species has not been provided a status by

SEMARNAT. This individual came from San Lucas in the Balsas-Tepalcatepec Depression

in Michoacan. Photo by Javier Alvarado- Diaz.

Based on the application of

this system, only a small per-

centage of the species in the

state would be scheduled to

receive the greatest amount of

attention. These 27 species in-

clude eight anurans, seven sala-

manders, one crocodylian, three

turtles, four lizards, and four

snakes. Whereas most of these

species appear to merit a threat-

ened status, inasmuch as 16 of

the 27 species are country-level

endemics and six are state-lev-

el endemics (22 species, 81.5%

of the 27), the herpetofauna of

Michoacan is characterized by

a higher level of endemism than

for the entire country of Mexico

(140 of 212 species [66.0%] vs.

736 of 1,227 species [60.0%]).

If endemism can be considered

an important criterion for listing

a species as threatened under the

IUCN system (which it is not, as

this system exists), then a sub-

stantial number of other candi-

dates are available for choosing

(Table 10), a significant issue

that needs to be addressed.

A similar issue is the num-

ber of species judged as Data

Deficient (Table 9). Of these 26

species, 17 are country and nine

are state level endemics. Assign-

ment of the DD status leaves

these species in limbo, and re-

quires additional fieldwork be-

fore applying for a change in a

species’ status. Other papers in

this special Mexico issue have

criticized the use of the DD cat-

egory, with Wilson et al. (2013b)

labeling these species as “threat

species in disguise.” The signif-

icance of such species can be ig-

nored in the “rush to judgment”

that sometimes accompanies

assessments conducted using

the IUCN system (NatureServe

Press Release 2007).

Another problem with the

use of the IUCN system is dis-

cussed in the lead-in paragraph

to this section, i.e., that some

species have not been evaluated

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Alvarado-Diaz et al.

(the NE species). Given the average cost of producing an

IUCN threat assessment for a single species ($534.12,

according to the figures in Stuart et al. 2010b), it takes a

considerable investment to assign a species to a category

other than NE. Nonetheless, one is left with relegating

such species to a “wastebasket of neglect.” In the case

of the Michoacan herpetofauna, 28 species fall into this

category, including nine lizards and 19 snakes (Table

9). To be fair, the distributions of most of these species

(21) extends outside of Mexico and thus were assessed

in a Central American Workshop held in May of 2012 in

Costa Rica (Rodriguez et al. 2013). At that workshop,

most of these species were assigned an LC status.

Adding more species to the LC category is not nec-

essarily a beneficial step, inasmuch as this category

was described as a “dumping ground” by Wilson et

al. (2013b), who opined that “a more discerning look

would demonstrate that many of these species should be

partitioned into IUCN categories other than LC,” e.g.,

the threat categories and NT. Currently, 127 of the 212

native species of amphibians and reptiles (59.9%) are

placed in the LC category (Table 9), which includes 31

anurans, one salamander, two turtles, 39 lizards, and 54

snakes. We question these assignments on the basis that

83 of these species are country -level endemics, and three

( Phyllodactylus duellmani, Aspidoscelis calidipes, and

Thamnophis postremus ) also are state-level endemics

(Table 7).

Table 10. Summary of the distributional status of amphibian and reptile families in Michoacan.

Families

Number

of

Species

Distributional Status

Non-endemic

(NE)

Country

Endemic (CE)

State Endemic

(SE)

Non-native

(NN)

Bufonidae

6

1

4

1

—

Craugastoridae

5

2

3

—

Eleutherodactylidae

5

—

3

2

—

Hylidae

11

5

6

—

Leptodactylidae

2

—

Microhylidae

2

—

Ranidae

11

2

7

1

Rhinophrynidae

1

—

Scaphiopodidae

1

—

Subtotals

44

16

23

4

1

Ambystomatidae

6

—

3

—

Plethodontidae

3

—

3

—

Subtotals

9

—

6

3

Caeciliidae

1

—

1

—

Subtotals

1

—

1

—

Totals

54

16

30

7

1

Crocodylidae

1

—

Subtotals

1

—

Cheloniidae

2

—

Dermochelyidae

1

—

Geoemydidae

2

1

—

Kinosternidae

2

1

—

Subtotals

7

5

2

—

Bipedidae

1

—

1

—

Anguidae

6

2

3

1

—

Corytophanidae

1

—

Dactyloidae

2

—

2

—

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Physiographic distribution and conservation of Michoacan herpetofauna

Gekkonidae

1

—

1

Helodermatidae

1

—

Iguanidae

3

1

2

—

Mabuyidae

1

—

Phrynosomatidae

20

5

15

—

Phyllodactylidae

5

—

3

2

—

Scincidae

6

—

6

—

Sphenomorphidae

1

—

Teiidae

8

3

4

1

—

Xantusiidae

1

—

1

—

Subtotals

58

16

37

4

1

Boidae

1

—

Colubridae

28

12

15

1

—

Dipsadidae

33

9

19

5

—

Elapidae

4

2

—

Leptotyphlopidae

4

2

1

—

Loxocemidae

1

—

Natricidae

11

3

7

1

—

Typhlopidae

1

—

1

Viperidae

10

2

7

1

—

Xenodontidae

2

—

2

—

Subtotals

95

32

53

9

1

Totals

161

54

92

13

2

Sum Totals

215

70

122

20

3

Rena bressoni. The Michoacan slender blindsnake is a state endemic, and its distribution is limited to the Balsas-Tepalcatepec

Depression. Its EVS has been estimated as 14, placing it at the lower end of the high vulnerability category, it has been judged as

Data Deficient by IUCN, and SEMARNAT considers it a Special Protection species. This individual was found in the municipality

of Tacambaro in Michoacan. Photo by Oscar Medina- Aguilar.

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Crotalus basiliscus. The west coast Mexican rattlesnake is distributed from southern

Sonora to northwestern Michoacan. In Michoacan, it is found in the Coastal Plain, Sierra

Madre del Sur, and the Balsas-Tepalcatepec Depression physiographic provinces. Its EVS

has been reported as 16, placing it in the middle of the high vulnerability category, it has

been assessed as Least Concern by IUCN, and it is regarded as a Special Protection species

by SEMARNAT. This individual is from San Mateo, on the coast of Jalisco.

Photo by Oscar Medina- Aguilar.

Crotalus pusillus. The Tancitaran dusky rattlesnake is found in the Sierra de Coalcoman

region of the Sien a Madre del Sur and the western portion of the Transverse Volcanic Axis.

Its EVS has been estimated as 18, placing it in the upper portion of the high vulnerability

category, it has been assessed as Endangered by IUCN, and it is considered as Threatened

by SEMARNAT. This individual came from Cerro Tancftaro, the highest mountain in

Michoacan, located in the west-central portion of the state. Photo by Javier Alvarado-Diaz.

The EVS (Environmental Vul-

nerability Score) system of con-

servation assessment first was

applied to the herpetofauna of

Honduras by Wilson and Mc-

Cranie (2004). Since that time,

this system has been applied

to the herpetofaunas of Belize

(Stafford et al. 2010), Guate-

mala (Acevedo et al. 2010),

Nicaragua (Sunyer and Kohler

2010), Costa Rica (Sasa et al.

2010), and Panama (Jaramillo et

al. 2010). In this special Mexi-

co issue, the EVS measure also

has been applied to the herpeto-

fauna of Mexico (Wilson et al.

2013a, b).

In this paper, we utilized the

scores computed by Wilson et al

(2013a,b), which are indicated

in Table 7 and summarized in

Table 11 for the 208 species for

which the scores are calculable.

We arranged the resultant scores

into three categories (low, me-

dium, and high vulnerability),

which were established by Wil-

son and McCranie (2004).

The EVS for members of the

Michoacan herpetofauna range

from 3 to 19 (Table 11). The

lowest score of 3 was calculat-

ed for three anurans (the bu-

fonid Rhinella marina , the hylid

Smilisca baudinii, and the ra-

nid Lithobates forreri) and one

snake (the leptotyphlopid Epic-

tia goudotii). The highest value

of 19 was assigned to the viperid

Crotalus tancitarensis.

The summed scores for the

entire herpetofauna vascillate

over the range, but still gener-

ally rise from the lower scores

of 3 through 5 to peak at 14 and

decline thereafter (Table 11).

Similar patterns are seen for am-

phibians and reptiles separately,

although the species numbers

for amphibians peak at an EVS

of 13 instead of 14, as is the case

for reptiles.

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Physiographic distribution and conservation of Michoacan herpetofauna

Table 11. Environmental Vulnerability Scores (EVS) for amphibian and reptile species in Michoacan, arranged by family. Shaded area to

the left encompasses low vulnerability scores, and to the right high vulnerability scores.

Families

Number

of

Species

Environmental Vulnerability Scores

6

8

10

11

12

13

14

15

16

17

18

19

Bufonidae

Craugastoridae

Eleutherodactylidae

Hylidae

11

Leptodactylidae

Microhylidae

Ranidae

10

Rhinophrynidae

Scaphiopodidae

Subtotals

43

Subtotals %

7.0

4.6

2.3

4.6

7.0

2.3

14.0

9.3

14.0

7.0

4.6

2.3

7.0

Ambystomatidae

Plethodontidae

Subtotals

Subtotals %

11.1

33.3

22.2

11.1

Caeciliidae

Subtotals

Subtotals %

100

Totals

53

Totals %

5.7

3.8

1.9

3.8

5.7

3.8

11.3

16.8

5.7

7.5

3.8

7.5

Crocodylidae

Subtotals

Subtotal %

100

Geoemydidae

Kinosternidae

Subtotals

Subtotal %

25.0

Bipedidae

Anguidae

Corytophanidae

Dactyloidae

Eublepharidae

Helodermatidae

Iguanidae

Mabuyidae

Phrynosomatidae

20

Phyllodactylidae

Scincidae

Sphenomorphidae

Teiidae

Xantusiidae

Subtotals

57

11

Subtotal %

3.5

5.3

1.8

7.0

1.8

12.3

14.0

5.3

19.3

15.7

14.0

Boidae

Colubridae

28

Dipsadidae

33

Elapidae

Leptotyphlopidae

Loxocemidae

Natricidae

Viperidae

11

To"

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Alvarado-Diaz et al.

Xenodontidae

2

—

1

—

1

—

Subtotals

93

1

3

6

7

8

2

4

6

3

11

12

13

10

3

2

1

Subtotal %

—

1.1

3.2

6.4

7.5

8.6

2.2

4.3

6.4

3.2

11.8

12.9

14.0

10.8

3.2

2.2

1.1

Totals

155

1

3

8

10

6

14

11

14

25

22

18

3

2

1

Total %

—

0.6

1.9

5.2

6.5

3.9

9.0

7.1

9.0

16.1

14.2

11.6

1.9

1.3

0.6

Sum Totals

208

4

3

4

10

13

9

8

20

17

23

28

26

20

7

2

1

Sum Totals %

—

1.9

1.4

1.9

4.8

6.3

4.3

3.8

9.6

8.2

11.1

13.5

12.5

9.6

3.3

1.0

0.5

After organizing the EVS into low, medium, and high categories, a number of conclusions of conservation sig-

nificance are apparent. The absolute and relative numbers for each of these categories, from low to high arranged

by major herpetofaunal group, are as follows: anurans

= 17 (39.5%), 17 (39.5%), 9 (21.0%); salamanders = 0

(0.0%), 5 (55.6%), 4 (44.4%); caecilians = 0 (0.0%), 1

(100%), 0 (0.0%); crocodylians = 0 (0.0%), 0 (0.0%), 1

(100%); turtles = 1 (25.0%), 2 (50.0%), 1 (25.0%); liz-

ards = 10 (17.6%), 19 (33.3%), 28 (49.1%); and snakes

= 28 (30.1%), 25 (26.9%), 40 (43.0%). The highest ab-

solute and relative numbers for each of the amphibian

groups fall into the medium range, evident when these

numbers are added, as follows: 17 (32.1); 23 (43.4); and

13 (24.5). For the reptile groups, the pattern is different

in that the largest absolute and relative numbers for all

groups, except for turtles, fall into the high range. Sum-

ming these numbers illustrates the general trend for rep-

tiles, in which numbers increase from low to high: 39

(25.2); 46 (29.7); and 70 (45.1).

The trend seen for reptiles also applies to the herpe-

tofauna as a whole. Of the 208 total species, 56 (26.9%)

are assigned to the low category, 69 (33.2%) to the medi-

um category, and 83 (39.9%) to the high category.

In summary, application of the EVS measure to the

members of the herpetofauna of Michoacan demon-

strates starkly that the absolute and relative numbers

increase dramatically from the low category of scores

through the medium category to the high category.

4. Comparing the results of the three

systems

When we compared the results of the three conservation

assessment systems, it was obvious that the EVS is the

only one for which the entire land herpetofauna of Mi-

choacan can be assessed. The EVS also is the only sys-

tem that provides a fair accounting of the distribution-

al status of species (state-level endemic, country-level

endemic, and non-endemic). Furthermore, this system

is cost-effective, as the authors of this paper and those

of the two on the Mexican herpetofauna in this special

Mexico issue assembled these contributions from their

homes, simply by using the communicative ability of

the Internet. The only disadvantage of the EVS is that

it does not apply to marine species; today, however, a

sizable number of conservation champions at least are

working with marine turtles. Thus, as noted by Wilson

et al. (2013b), “given the geometric pace at which envi-

ronmental threats worsen, since they are commensurate

with the rate of human population growth, it is important

to have a conservation assessment measure that can be

applied simply, quickly, and economically to the species

under consideration.” The EVS is the only one of the

three systems we examined with this capacity.

Conclusions and Recommendations

1. Conclusions

A broad array of habitat types are found in Michoacan,

ranging from those at relatively lower elevations along

the Pacific coastal plain and in the Balsas-Tepalcate-

pec Depression to those at higher elevations in the Si-

erra Madre del Sur, the Transverse Volcanic Axis, and

the Central Plateau. In total, 215 species of amphibians

and reptiles are recorded from the state, including 212

native and three non-native species ( Lithobates cates-

beianus, Hemidactylus frenatus, and Ramphotyphlops

braminus). The native amphibians comprise 43 anurans,

nine salamanders, and one caecilian. The native reptiles

constitute 151 squamates (including the marine Pelamis

platura ), seven turtles (including the marine Chelonia

mydas, Dermochelys coriacea, and Lepidochelys oliva-

cea ), and one crocodylian.

With respect to the number of physiographic prov-

inces inhabited, the numbers drop consistently from the

lowest to the highest occupancy figures (i.e., one through

five). The number of taxa in each of the provinces, in

decreasing order, is as follows: Sierra Madre del Sur (103

species); Balsas-Tepalcatepec Depression (98); Trans-

verse Volcanic Axis (97); Coastal Plain (71); and Central

Plateau (29). Among the five provinces, the represen-

tation of the major herpetofaunal groups is as follows:

anurans = Balsas-Tepalcatepec Depression; salamanders

= Transverse Volcanic Axis (all species limited here);

caecilians = Sierra Madre del Sur and Transverse Volca-

nic Axis (single species limited to these two provinces);

lizards = Sierra Madre del Sur; snakes = Sierra Madre del

Sur; turtles = Coastal Plain; and crocodylians = Coastal

Plain (single species limited here). The degree of herpe-

tofaunal resemblance is greatest between the Balsas-Te-

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Physiographic distribution and conservation of Michoacan herpetofauna

palcatepec Depression and the Sierra Madre del Sur. The

greatest resemblance of the Coastal Plain herpetofauna

also is to that of the Balsas-Tepalcatepec Depression.

Finally, the greatest resemblance of the herpetofauna

of the Transverse Volcanic Axis is to that of the Central

Plateau, and vice versa. Within Michoacan, close to one-

half of the native herpetofauna is limited in distribution

to a single physiographic province, in the following de-

creasing order: Transverse Volcanic Axis, Coastal Plain,

Balsas-Tepalcatepec Depression, Sierra Madre del Sur,

and Central Plateau. Most of these single-province spe-

cies also are country-level endemics.

We employed three systems for assessing the conser-

vation status of members of the Michoacan herpetofauna

(SEMARNAT, IUCN, and EVS). The SEMARNAT sys-

tem was developed for use in Mexico by the Secretarfa

de Medio Ambiente y Recursos Naturales. Although

widely used in Mexico, when this system is applied to

the herpetofauna of Michoacan it leaves almost one-

half of the species unassessed (i.e., having “no status”).

Nevertheless, we documented and analyzed the results

applying this system to the herpetofauna of Michoacan.

Given the significantly incomplete coverage of the

SEMARNAT system, we found it insufficiently useful

for our purposes.

The IUCN system is applied and used globally. Its

categories are broadly recognized (e.g., Critically En-

dangered, Endangered, and Vulnerable, the three so-

called threat categories). Although this system presently

has been applied to a greater proportion of the herpe-

tofauna of Michoacan (compared to the SEMARNAT

system), it has not been applied to about 13% of the

species. Furthermore, we question the applicability of

some aspects of this system, especially with regard to

the significant use of the Data Deficient category and

the overuse of the Least Concern category. In addition,

the expense of creating IUCN threat assessments and the

manner in which they are created (e.g., workshops that

bring together workers from far-flung areas of the world

to a single location within the area of evaluation for sev-

eral days) often is cost-prohibitive. We also found this

system deficient in presenting a useful appraisal of the

conservation status of Michoacan’s herpetofauna.

The EVS system originally was developed for use

with amphibians and reptiles in Honduras, but later was

expanded for use elsewhere in Central America. In this

Special Mexico Issue of Amphibian & Reptile Conser-

vation, it was applied to all of the native amphibians and

non-marine reptiles of Mexico (Wilson et al. 2013a,b).

We adopted the scores developed in these two papers for

use with the Michoacan herpetofauna, and analyzed the

results. We discovered that once all of the species were

evaluated using the EVS system and allocated to low,

medium, and high score categories, the number of spe-

cies increases strikingly from the low through the medi-

um to the high category.

2. Recommendations

Porthidium hespere. The western hog-nosed viper inhabits the coastal plain of western

Mexico, from southeastern Colima to central Michoacan. Its EVS has been reported as

18 , placing it in the upper portion of the high vulnerability category, it has been judged as

Data Deficient by IUCN, and assigned a Special Protection status by SEMARNAT. This

individual is from Coahuayana on the coast of Michoacan. Photo by Oscar Medina- Aguilar.

Based on our conclusions, a

number of recommendations

follow:

1 . Given that the degree of her-

petofaunal endemism in Micho-

acan is greater than that for the

country of Mexico, and that a

substantial number of those en-

demic species are known only

from the state, the level of pro-

tection afforded to the state’s

herpetofauna is of major conser-

vation interest. One hundred and

twenty-one species are endemic

at the country level and an addi-

tional 20 are endemic at the state

level. Thus, the total for these

two groups is 141 (66.5% of the

total native herpetofauna), a fig-

ure 6.5% higher than that for the

country (Wilson et al. 2013a,b).

The species with the most con-

servation significance are the 20

state endemics, and we recom-

mend a conservation assessment

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166

Alvarado-Diaz et al.

of the state’s herpetofauna that focuses on the

state- and country-level endemic species.

2. Michoacan contains a sizable number of protected

areas at the global, national, state, and local lev-

els. Because the distribution of the herpetofauna

in these areas only is being determined, we recom-

mend that this work be accelerated to form a da-

tabase for creating a state-level conservation plan.

3. An evaluation of the level of protection afford-

ed to the state’s herpetofauna in protected areas

is critical for determining areas with high species

richness, a high number of endemic species, or

species at risk, as well as the degree of overlap

within the various protected areas.

4. We recommend an evaluation of all the protected

areas in the state, based on their ability to support

viable populations of the resident herpetofauna.

5. Once a distributional database is assembled for

the state’s herpetofauna in protected areas, and a

capacity analysis completed, a robust conserva-

tion plan needs to be developed and implemented.

6. Considering that agriculture, logging, and cattle

ranching are the leading factors in the local ex-

tirpation and extinction of ecosystems and their

resident species, and that human-modified en-

vironments now are the dominant landscapes in

the state, the potential for the conservation of the

herpetofauna in these environments needs to be

evaluated. Management strategies that allow for

the maximal numbers of herpetofaunal species to

survive and thrive in these altered landscapes also

need to be defined.

7. Ultimately, humans protect only what they ap-

preciate, and thus a conservation management

plan must encompass environmental education

programs for all groups of people, especially the

young, as well as the involvement of local people

in implementing these programs.

Acknowledgments. — We are indebted to our col-

leagues Jerry D. Johnson and Vicente Mata-Silva for

generously sharing the data accumulated for their papers

on Mexican amphibians and reptiles in this Special Mex-

ico Issue. We extend our gratitude to Louis W. Porras for

kindly offering his counsel and assistance on a number

of issues that arose while preparing this paper, and to

he and Donald E. Hahn for providing needed literature.

Louis was especially helpful in providing us a remark-

able job of copy-editing our work. We also are grateful

to Craig Hassapakis, the editor of this journal, for his

unflagging encouragement, enthusiasm, and support of

our work on this paper. In addition, we thank Jonatan

Torres for his help in updating the list of amphibians and

reptiles of Michoacan. Finally, we are grateful to Uri

Amphib. Reptile Conserv. | http://amphibian-reptile-conservation.org 167

Garcia- Vazquez and Aurelio Ramirez-Bautista for their

helpful reviews of our work. Funding for fieldwork was

provided by the Consejo de Investigacion Cientifica,

UMSNH.

Literature Cited

Acevedo M, Wilson LD, Cano EB, Vasquez-Almazan C.

2010. Diversity and conservation status of the Gua-

temalan herpetofauna. Pp. 406-435 In: Conservation

of Mesoamerican Amphibians and Reptiles. Editors,

Wilson LD, Townsend JH, Johnson JD. Eagle Moun-

tain Publishing, LC, Eagle Mountain, Utah, USA.

Alvarado-Diaz J, Campbell JA. 2004. A new montane

rattlesnake (Viperidae) from Michoacan, Mexico.

Herpetologica 60: 281-286.

Alvarado-Diaz J, Estrada- Virgen A, Suazo-Ortuno I.

2007. Natural history notes on Crotalus tancitaren-

sis (Serpentes: Viperidae). Herpetological Review 38:

155-157.

Bryson Jr. RW, Murphy RW, Graham MR, Lathrop A,

Lazcano D. 2011. Ephemeral Pleistocene woodlands

connect the dots for highland rattlesnakes of the Cro-

talus intermedins group. Journal of Biogeography

2011 : 1 - 12 .

Campbell JA. 2007. Crotalus tancitarensis. In: IUCN

2012. IUCN Red List of Threatened Species. Version

2012.2. Available: www.iucnredlist.org [Accessed:

15 March 2013].

Casas- Andreu G, McCoy CJ. 1979. Anfibios y Reptiles

de Mexico. Limusa, Mexico DF, Mexico.

Casas- Andreu G, Valenzuela-Lopez G, Ramirez-Bautis-

ta A. 1991. Como hacer una coleccion de anfibios y

reptiles. Cuademos del Instituto de Biologia 10. Uni-

versidad Nacional Autonoma de Mexico, Mexico DF,

Mexico.

Chernela J. 2012. A species apart: ideology, science and

the end of life. Pp. 18-38 In: The Anthropology of

Extinction, Essays on Culture and Species Death. Ed-

itor, Sodikoff GM. Indiana University Press, Bloom-

ington, Indiana, USA.

CIA World Factbook. Available: www.cia.gov [Ac-

cessed: 21 February 2013].

Contreras AA. 1942. Mapa de las Provincias Clima-

toldgicas de la Republica Mexicana. Secretarfa de

Agricultura y Fomento, Direccion de Geografia, Me-

teorologia e Hidrologia, Instituto Geografico, Mexico.

Crump ML, Scott NJ. 1994. Visual encounter surveys.

Pp. 84-92 In: Measuring and Monitoring Biological

Diversity, Standard Methods for Amphibians . Editors,

Heyer WR, Donnelly MA, McDiarmid RW, Hayek

LAC, Foster MS. Smithsonian Institution Press,

Washington DC, USA.

Duellman WE. 1961. The amphibians and reptiles of Mi-

choacan, Mexico. University of Kansas Publications,

Museum of Natural History 15: 1-148.

September 2013 | Volume 7 | Number 1 | e71

Physiographic distribution and conservation of Michoacan herpetofauna

Duellman WE. 1965. A biogeographic account of herpe-

tofauna of Michoacan, Mexico. University of Kansas

Publications, Museum of Natural History 15: 627-709.

Duellman WE. 2001. The Hylid Frogs of Middle Ameri-

ca (2 volumes). Society for the Study of Amphibians

and Reptiles, Contributions in Herpetology, Volume

18, Ithaca, New York, USA.

Faivovich J, Haddad CFB, Garcia PC A, Frost DR,

Campbell JA, Wheeler WC. 2005. Systematic review

of the frog family Hylidae, with special reference to

Hylinae: phylogenetic analysis and taxonomic revi-

sion. Bulletin of the American Museum of Natural

History 294: 1-240.

Flores -Villela O, Canseco-Marquez F. 2004. Nuevas es-

pecies y cambios taxonomicos para la herpetofauna

de Mexico. Acta Zoologica Mexicana 20: 115-144.

Flores-Villela O, Canseco-Marquez F, Ochoa-Ochoa

FM. 2010. Geographic distribution and conservation

of the Mexican Central Highlands herpetofauna. Pp.

302-321 In: Conservation of Mesoamerican Amphib-

ians and Reptiles. Editors, Wilson FD, Townsend JH,

Johnson JD. Eagle Mountain Publishing, FC, Eagle

Mountain, Utah, USA.

Flores-Villela OA, Mendoza-Quijano F, Gonzalez-Porter

G. 1995. Recopilacion de las Claves para la Deter-

minacion de Anfibios y Reptiles de Mexico. Publica-

ciones Especiales del Museo de Zoologfa, No. 10,

Universidad Nacional Autonoma de Mexico, Facul-

tad de Ciencias, Departamento de Biologfa, Mexico

DF, Mexico.

Gonzalez-Hernandez AJ, Garza-Castro JM. 2006. Her-

petofauna del municipio de Nuevo Urecho, Micho-

acan, Mexico. Pp. 140-152 In: Inventarios Herpeto-

faunisticos de Mexico: Avances en el Conocimiento de

su Biodiversidad. Editors, Ramlrez-Bautista A, Can-

seco-Marquez F, Mendoza-Quijano F. Publicaciones

de la Sociedad Herpetologica Mexicana 3: 140-151.

Huacuz ED. 1995. Serpientes del Estado de Michoacan.

M.S. Thesis, Universidad Nacional Autonoma de

Mexico, Mexico DF, Mexico.

IUCN. 2010. Guidelines for using the IUCN Red Fist

categories and criteria. Available: www.iucnredlist.

org [Accessed: 18 March 2013].

Jaramillo C, Wilson FD, Ibanez R, Jaramillo F. 2010.

The herpetofauna of Panama: distribution and conser-

vation status. Pp. 604-673 In: Conservation of Meso-

american Amphibians and Reptiles. Editors, Wilson

FD, Townsend JH, Johnson JD. Eagle Mountain Pub-

lishing, FC, Eagle Mountain, Utah, USA.

Florente-Bousquets J, Ocegueda S. 2008. Estado del con-

ocimiento de la biota. Pp. 283-322 In: Capital Natural

de Mexico. Compilers, Soberon J, Halffter G, Florente-

Bousquets J. CONABIO, Mexico DF, Mexico.

Medina-Aguilar O, Alvarado-Dlaz J, Suazo-Ortuno I.

2011. Herpetofauna de Tacambaro, Michoacan, Mex-

ico. Revista Mexicana de la Biodiversidad 82: 1 194—

Amphib. Reptile Conserv. | http://amphibian-reptile-conservation.org 168

1202 .

NatureServe Press Release. 2007. New Assessment of

North American reptiles finds rare good news. Avail-

able: www.natureserve.org/aboutUs/PressReleases/

NatureServe%20reptile%20assessmentRed%20

Fist%20news%20release%209- 12-07 [Accessed: 21

May 2012].

Nieto Montes de Oca A, Poe S, Scarpetta S, Gray F,

Fieb CS. 2013. Synonyms for some species of Mex-

ican anoles (Squamata: Dactyloidae). Zootaxa 3637:

484-492.

Ramlrez-Bautista A. 1994. Manual y Claves Ilustradas

de los Anfibios y Reptiles de la Region de Chamela,

Jalisco, Mexico. Cuaderno No. 23, Instituto de Bi-

ologla, Universidad Nacional Autonoma de Mexico,

Mexico DF, Mexico.

Rodriguez JE, Bolanos F, Matamoros Y (Editors). 2013.

Taller para evaluar el estado de conservacion de los

reptiles de Centroamerica. Utilizando los lineamien-

tos de las Fistas Rojas de la UICN. 6-10 de mayo,

2012. Estacion Biologica Palo Verde, Bagaces, Gua-

nacaste, Costa Rica. UICN/SSC Conservation Breed-

ing Specialist Group-Mesoamerica (CBSG Meso-

america), Costa Rica.

Sasa M, Chaves G, Porras FW. 2010. The Costa Rican

herpetofauna: conservation status and future perspec-

tives. Pp. 510-603 In: Conservation of Mesoameri-

can Amphibians and Reptiles. Editors, Wilson FD,

Townsend JH, Johnson JD. Eagle Mountain Publish-

ing, FC, Eagle Mountain, Utah, USA.

SEDUE and UMSNH. 2000. Catalogo de la Biodiversi-

dad en Michoacan. Secretarla de Desarrollo Urbano

y Ecologla, Universidad Michoacana San Nicolas de

Hidalgo, Morelia, Michoacan, Mexico.

Smith HM, Taylor EH. 1945. An annotated checklist and

keys to the snakes of Mexico. Bulletin of the United

States National Museum 187: 1-239.

Smith HM, Taylor EH. 1948. An annotated checklist and

keys to the amphibia of Mexico. Bulletin of the Unit-

ed States National Museum 194: 1-118.

Smith HM, Taylor EH. 1950. An annotated checklist and

keys to the reptiles of Mexico exclusive of the snakes.

Bulletin of the United States National Museum 199:

1-253.

Stafford PJ, Walker P, Edgar P, Penn MG. 2010. Distribu-

tion and conservation of the herpetofauna of Belize.

Pp. 370-405 In: Conservation of Mesoamerican Am-

phibians and Reptiles. Editors, Wilson FD, Townsend

JH, Johnson JD. Eagle Mountain Publishing, FC,

Eagle Mountain, Utah, USA.

Stuart SN, Chanson JS, Cox NA, Young BE. 2010a.

The global decline of amphibians: current trends

and future prospects. Pp. 2-15 In: Conservation of

Mesoamerican Amphibians and Reptiles. Editors,

Wilson FD, Townsend JH, Johnson JD. Eagle Moun-

tain Publishing, FC, Eagle Mountain, Utah, USA.

September 2013 | Volume 7 | Number 1 | e71

Alvarado-Diaz et al.

Stuart SN, Wilson EO, McNeely JA, Mittermeier RA,

Rodriguez JR 2010b. The barometer of life. Science

328: 177.

Sunyer J, Kohler G. 2010. Conservation status of the

herpetofauna of Nicaragua. Pp. 488-509 In: Conser-

vation of Mesoamerican Amphibians and Reptiles.

Editors, Wilson LD, Townsend JH, Johnson JD. Ea-

gle Mountain Publishing, LC, Eagle Mountain, Utah,

USA.

Torres MY. 2011. Herpetofauna del Municipio de Ario

de Rosales, Michoacan, Mexico. MS Thesis, Univer-

sidad Michoacana de San Nicolas de Hidalgo, Morel-

ia, Michoacan, Mexico.

Townsend JH, Wilson LD. 2010. Conservation of the

Honduran herpetofauna: issues and imperatives. Pp.

460-487 In: Conservation of Mesoamerican Amphib-

ians and Reptiles. Editors, Wilson LD, Townsend JH,

Johnson JD. Eagle Mountain Publishing, LC, Eagle

Mountain, Utah, USA.

Vargas- Santamarfa F, Flores-Villela O. 2006. Estudio

herpetofaunistico en el Playon de Mexiquillo y areas

adjacentes en la costa sur del estado de Michoacan,

Mexico. Pp. 110-136 In: Inventarios Herpetofaumsti-

cos de Mexico: Avances en el Conocimiento de su

Biodiver sidad. Editors, Ramfrez-Bautista A, Canse-

co-Marquez L, Mendoza-Quijano F. Publicaciones de

la Sociedad Herpetologica Mexicana 3, Mexico, DF,

Mexico.

Villasenor GLE (Editor). 2005. La Biodiversidad en

Michoacan: Estudio de Estado. Comision Nacional

para el Conocimiento y Uso de la Biodiversidad, Sec-

retarfa de Urbanismo y Medio Ambiente, UMSNH,

Mexico DF, Mexico.

Wilson EO. 2002. The Future of Life. Alfred A. Knopf,

New York, New York, USA.

Wilson LD, Johnson JD. 2010. Distributional patterns

of the herpetofauna of Mesoamerica, a biodiversity

hotspot. Pp. 30-235 In: Conservation of Mesoamerican

Amphibians and Reptiles. Editors: Wilson LD,

Townsend JH, Johnson JD. Eagle Mountain Publish-

ing, LC, Eagle Mountain, Utah, USA.

Wilson LD, Mata-Silva V, Johnson JD. 2013a. A conser-

vation reassessment of the reptiles of Mexico based

on the EVS measure. Amphibian & Reptile Conser-

vation 7(1): 1-47.

Wilson LD, Johnson JD, Mata-Silva V. 2013b. A con-

servation reassessment of the amphibians of Mexico

based on the EVS measure. Amphibian & Reptile

Conservation 7(1): 97-127.

Wilson LD, McCranie JR. 2004. The conservation status

of the herpetofauna of Honduras. Amphibian & Rep-

tile Conservation 3(1): 6-33.

Wilson LD, Townsend JH, Johnson JD. 2010. Conserva-

tion of Mesoamerican Amphibians and Reptiles. Ea-

gle Mountain Publishing, LC, Eagle Mountain, Utah,

USA.

Addendum

After this paper was placed in proof, we discovered a

report of a new Michoacan record for Coniophanes me-

lanocephalus (Carbajal-Marquez RA, Quintero-Dfaz

GE, and Domfnguez-De La Riva MA. 2011. Geographic

distribution. Coniophanes melanocephalus [Black-hea-

ded Stripeless Snake] Herpetological Review 42: 242).

The specimen was found in “subtropical dry forest” at

Hoyo del Aire, Municipality of Taretan, at an elevation

of 887 m. This locality lies within the northernmost fin-

ger of the Balsas-Tepalcatepec Depression in central Mi-

choacan. The EV S of Coniophanes melanocephalus has

been assessed as 14, placing it in the high vulnerability

category, its IUCN status reported as DD (Wilson et al.

2013), and no status is available in the SEMARNAT sys-

tem (www.semarnat.gob.mx).

Received: 26 March 2013

Accepted: 04 June 2013

Published: 03 September 2013

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Physiographic distribution and conservation of Michoacan herpetofauna

Javier Alvarado-Dfaz is a herpetologist and professor of vertebrate zoology and herpe-

tology at the Universidad de Michoacan, Mexico. His main interest in herpetology

is the conservation of Mexican amphibians and reptiles, from sea turtles to montane

snakes. He is a member of the Sistema Nacional de Investigadores and has pub-

lished a number of peer-reviewed papers and books on conservation and ecology of

the Mexican herpetofauna.

Ireri Suazo Ortuno is a herpetologist and professor of zoology and herpetology at

the Universidad de Michoacan, Mexico. Her principal interest in herpetology is

the conservation of amphibians and reptiles in human modified landscapes. She

is a member of the Sistema Nacional de Investigadores, and has published peer-

reviewed papers on the ecology of tropical herpetofaunal assemblages. She is also

the director of the Instituto de Investigaciones sobre los Recursos Naturales de la

Universidad Michoacana de San Nicolas de Hidalgo.

Larry David Wilson is a herpetologist with lengthy experience in Mesoamerica, to-

taling six collective years (combined over the past 47). Larry is the senior editor

of the recently published Conservation of Mesoamerican Amphibians and Reptiles

and a co-author of seven of its chapters. He retired after 35 years of service as

Professor of Biology at Miami-Dade College in Miami, Florida. Larry is the author

or co-author of more than 290 peer-reviewed papers and books primarily on herpe-

tology, including the 2004 Amphibian & Reptile Conservation paper entitled “The

conservation status of the herpetofauna of Honduras.” His other books include The

Snakes of Honduras, Middle American Herpetology, The Amphibians of Honduras,

Amphibians & Reptiles of the Bay Islands and Cayos Cochinos, Honduras, The

Amphibians and Reptiles of the Honduran Mosquitia, and Guide to the Amph ibians

& Reptiles of Cusuco National Park, Honduras. He also served as the Snake Sec-

tion Editor for the Catalogue of American Amphibians and Reptiles for 33 years.

Over his career, Larry has authored or co-authored the description of 69 currently

recognized herpetofaunal species and six species have been named in his honor,

including the anuran Craugastor lauraster and the snakes Cerrophidion wilsoni,

Myriopholis wilsoni, and Oxybelis wilsoni.

Oscar Medina-Aguilar graduated from the Facultad de Biologfa of the Universidad

Michoacana de San Nicolas de Hidalgo in 2011. He studied the herpetofauna of

Tacambaro, Michoacan, as part of his degree requirements. His interests include the

systematics and distribution of the amphibians and reptiles of Mexico. In 2011, the

results of his study of the herpetofauna of Tacambaro were published in the Revista

Mexicana de Biodiversidad.

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CONTENTS

Administration, journal information (Instructions to Authors), and copyright notice Inside front cover

Larry David Wilson — Preface {Amphibian & Reptile Conservation Special Mexico Issue) i

Jerry D. Johnson, Louis W. Porras, Gordon W. Schuett, Vincente Mata-Silva, and Larry David Wilson. —

Dedications {Amphibian & Reptile Conservation Special Mexico Issue) iii

Larry David Wilson, Vicente Mata-Silva, and Jerry D. Johnson — A conservation reassessment of the rep-

tiles of Mexico based on the EVS measure 1

Louis W. Porras, Larry David Wilson, Gordon W. Schuett, and Randall S. Reiserer — A taxonomic re-

evaluation and conservation assessment of the common cantil, Agkistrodon bilineatus (Squamata: Viperi-

dae): a race against time 48

Randall S. Reiserer, Gordon W. Schuett, and Daniel D. Beck — Taxonomic reassessment and conservation

status of the beaded lizard, Heloderma horridum (Squamata: Helodermatidae) 74

Larry David Wilson, Jerry D. Johnson, and Vicente Mata-Silva — A conservation reassessment of the am-

phibians of Mexico based on the EVS measure 97

Javier Alvarado Diaz, Ireri Suazao-Ortuno, Larry David Wilson, and Oscar Medina-Aguilar — Patterns

of physiographic distribution and conservation status of the herpetofauna of Michoacan, Mexico 128

Table of Contents Back cover

VOLUME 7

2013

NUMBER 1