Amphibians of Costa Rica: A Field Guide

527 Pages·2017·58.66 MB·English

by  Twan Leenders

w
T AN LE E N 0 E R s
AZ ONA TROPICAL PUBLICATION
Maps
On distribution maps, the thicker contour lines indicate an elevation of 3,275 ft
(1,000 m); the thinner contour lines indicate an elevation of 6,650 ft (2,000 m).
Gray shading indicates a species'
known historic range (roughly
before the year 2000), while
yellow shading indicates its
currently known range.
Note that all similar species
presented at the end of each
account are known to (potentially)
co-occur with the species
described in that section. If a
very similar-looking species that
does not have an overlapping
distribution range is presented,
this is clearly indicated.
...
Costa Rica contains five
.., ecoregions that are relevant to
,
local amphibians (see p. 3). Each
species account in this book
displays an ecoregion bar that
Ecoregions bar
indicates the primary ecoregions
where a particular species is
expected to occur.
Measurements
The standard length of an animal is the straight-line distance between the tip of its snout
and the posterior edge of its vent (essentially the length of its head and body); the total
length includes the length of the tail (which may be broken or incomplete in some cases
and is generally not the best measure of an animal's size). For caecilians and frogs,
which do not have a tail, the standard length equals the total length.
Gymnophiona
(Caecilians) Standard length = total length
Caudata
(Salamanders)
Standard length
Total length
(..
C
~~_,_....--
Standard length = total length
Anura
(Frogs & Toads}
Illustrations
Species accounts for most anura are
accompanied by schematic drawings
showing diagnostic features of their
hands and feet, including the amount of
webbing and the shape of finger and toe
disks (when present). Note that specific
fingers and toes are identified throughout
the text by roman numerals; digits are
numbered from those closest to the body
axis outward, as shown here.
( )
The hands and feet of salamanders are
very similar in terms of their appearance
and the amount of webbing (but note
that salamander hands invariably have
four digits, whereas their feet have five).
Therefore, only a foot is illustrated in the
salamander accounts.
In toads (family Bufonidae) the shape
and size of the parotoid glands, as well
as the presence and shape of the cranial
crests, are more diagnostic than the
hands and feet; species accounts in that
family are therefore accompanied by an
illustration of their head.
Amphibians
of Costa Rica
A FIELD GUIDE
TWAN LEENDERS
A Zona Tropical Publication
FROM
Comstock Publishing Associates
a division of
Cornell University Press
Ithaca and London
Text copyright© 2016 byTwan Leenders
Illustrations and range maps copyright© 2016 by Twan Leenders
Photographs copyright© 2016 by respective photographers
All rights reserved. Except for brief quotations in a review, this book, or parts
thereof, must not be reproduced in any form without permission in writing
from the publishers. For information within Costa Rica, visit Zona Tropical at
www.zonatropical.net. For information in the rest of the world, address Cornell
University Press, Sage House, 512 East State Street, Ithaca, New York 14850, or
visit www.cornellpress.cornell.edu.
First published 2016 by Cornell University Press
First printing, Cornell Paperbacks, 2016
Printed in China
Library of Congress Cataloging-in-Publication Data
Names: Leenders, Twan, author.
Title: Amphibians of Costa Rica : a field guide I Twan Leenders.
Description: Ithaca : Comstock Publishing Associates, a division of Cornell University Press,
2016. I ''A Zona Tropical publication:' I Includes bibliographical references and index.
Identifiers: LCCN 2016021844 I ISBN 9781501700620 (pbk.: alk. paper)
Subjects: LCSH: Amphibians-Costa Rica-Identification.
Classification: LCC QL656.C783 L43 2016 I DDC 597.8097286-dc23
LC record available at https://lccn.loc.gov/2016021844
Zona Tropical Press ISBN 978-0-9894408-3-7
Cornell University Press strives to use environmentally responsible suppliers
and materials to the fullest extent possible in the publishing of its books. Such
materials include vegetable-based, low-VOC inks and acid-free papers that are
recycled, totally chlorine-free, or partly composed of nonwood fibers. For further
information, visit our website at www.cornellpress.cornell.edu.
Paperback printing 10 9 8 7 6 5 4 3 2 1
Book concept design: Dave Huth and Gabriela Wattson
Book design: Gabriela Wattson
For those with a curious mind, a love of
nature, and a desire to learn: share that
passion widely so that fi1ture generations
will be able to enjoy the stars oft his book!

Contents
Foreword by Dr. Robin Moore ................................................... viii
Acknowledgments ......................................................................... ix
Introduction .................................................................................... I
Caecilians ..................................................................................... 10
Family Caeciliidae ............................................................... 15
Family Dermophiidae .......................................................... 19
Salamanders ................................................................................. 32
Family Plethodontidae ......................................................... 36
Frogs and Toads ......................................................................... 144
Family Bufonidae ............................................................... 150
Family Centrolenidae ......................................................... 191
Family Craugastoridae ....................................................... 226
Family Dendrobatidae ........................................................ 291
Family Eleutherodactylidae ............................................... 314
Family Hemiphractidae ...................................................... 333
Family Hylidae ................................................................... 337
Family Leptodactylidae ..................................................... 449
Family Microhylidae .......................................................... 465
Family Ranidae .................................................................. 474
Family Rhinophrynidae ..................................................... 486
Family Strabomantidae ...................................................... 489
Glossary ..................................................................................... 513
Bibliography .............................................................................. 517
Photo Credits .............................................................................. 525
Index .......................................................................................... 527
Foreword
If there were a pub quiz on Central American amphibians, I would feel pretty confi
dent about winning if I were on Twan Leenders' team.
I have been fortunate to accompany Twan into the rainforest habitat in which he is
so at home, bearing witness to his eagle eyes, fast hands, and astounding understanding
of natural history. Quite where he stores his encyclopedic knowledge is beyond me, but
it's hard to spend time with him in the field without hoping that at least some of it is
absorbed like water through a frog's skin.
But what impresses me even more than his knowledge is his passion for sharing
it. Few people are capable of doing this so graciously and with such good cheer. This
new field guide illuminates the natural history of Costa Rica's rich amphibian fauna
through range maps and detailed but engaging descriptions that will transport you to
the forest floor, rolling a mossy log in the hopes of finding an elusive caecilian.
But it is the brilliant photographs of animals on luminous white backgrounds
that draw the eye, page after page. These crisp images reveal features-the eardrums
on a poison dart frog, for example-not easily seen in the field. It is this combination
of beautiful photographs and fascinating text that makes this book such an invaluable
resource.
Understanding is the first step to caring, and what excites me most about this
book is the possibility that it will grow the community of people who are fascinated
by amphibians-and eager to protect them. And we can all do something. Whether
you are a hiker recording an important species sighting on your phone or a conserva
tionist deciding which forests to protect and manage, this book will be an invaluable
and inspiring resource.
I grew up looking for amphibians in the moors of Scotland, where I had the
chance offinding four amphibian species. I thought this was diversity. The moment I
entered the humid forests of Costa Rica I was left mesmerized as every swing of the
headlamp illuminated something different. Such an explosion of diversity in sizes,
colors, and forms is as daunting as it is exciting. In order to understand that diversity,
and truly appreciate the richness of amphibians in Costa Rica, I would highly recom
mend having Twan by your side. Failing that, this guide is the next best option.
Dr. Robin Moore
Author, In Search ofL ost Frogs: The Quest to
Find the World's Rarest Amphibians
Acknowledgments
This book is the result of nearly 25 years of studying the amphibians of Costa Rica,
dozens of trips to the region, countless nights spent hiking rainforest trails or wading
through streams and swamps in search of frogs and salamanders, and hundreds of
hours wrangling jumpy and squirmy creatures to obtain photographs. Although I
shudder at how much time and effort went into this pursuit, all of this pales in com
parison to the cumulative exploits of many, many other students of Costa Rican am
phibians whose work-published or shared in person-forms the foundation of this
book. I would like to express my appreciation to all those people whose love of na
ture and natural history study, focused on some of my favorite creatures in the world,
helped shape this book in many ways.
Furthermore, I would like to acknowledge the support of the people most affected
by my work: my wife and kids. Casey, Madeleine, and Jason tolerate my absence several
times a year for field work and, lately, suffered the loss of considerable family time while
I was writing this book. No other people have invested as much in this book, and I am
exceedingly grateful for their love and enthusiasm.
Many people have helped make this project possible, and there simply is not
enough room here to list and thank them all. I would be remiss, however, to not extend
special appreciation to Tim Paine and Alex Shepack, with whom I have shared many
memorable times in the field over the years. Others who have generously contributed
time, effort, experience, and insight over the years, in ways that have improved this
project, include Juan Abarca, Victor Acosta Chaves, Abel Batista, Clay Bolt, Peter
Dahlquist, Don Filipiak, Sean Graesser, Ann Gutierrez, Andreas Hertz, Dave Huth,
Robin Moore, Juan Pineda, Michael Roy, Stanley Salazar, Angel Solis, Jose Solis, Javier
Sunyer, and David Wake. A special thanks goes to all the students who have joined me
on a variety of research trips, and to Wendy Welshans and Laurie Doss, who, through
their efforts, continue to introduce young people to the marvels of tropical rainforest
ecology. Greg Watkins-Colwell and the rest of the staff at the Division of Vertebrate
Zoology of Yale University's Peabody Museum of Natural History helped support as
pects of the research for this book and facilitated access to specimens.
Not all of the images and materials provided by the following people made it into
the final design of this book, but their kind contributions were nevertheless extremely
valuable, and I acknowledge them here: Cesar Barrio-Amoros, Eduardo Boza Oviedo,
David Cannatella, Luis Coloma, William Duellman, Cesar Jaramillo, Karl-Heinz
Jungfer, Karen Lips, Stefan Lotzkat, Piotr Naskrecki, Kenji Nishida, Tobias Palmberg,
Todd Pierson, Marcos Ponce, Robert Puschendorf, Ignacio de la Riva, Sean Rovito,
Paddy Ryan, Rob Schell, Jen Stabile, Steven Whitfield, and Brad Wilson. (Detailed
photo credits are provided on page 525.)
Ultimately, it was John McCuen, of Zona Tropical Press, who made sure that
this book became a reality-which is truly an accomplishment!
Thank you all!
Twan Leenders