Middle American Frogs of the Hyla microcephala Group   By: M. J. Fouquette

Museum of Natural History

Volume 17, No. 12, pp. 517 557, pls. 13 16, 9 figs. March 20, 1968

Middle American Frogs of the Hyla microcephala Group

BY

WILLIAM E. DUELLMAN AND M. J. FOUQUETTE, JR.

University of Kansas Lawrence 1968

University of Kansas Publications, Museum of Natural History

Editors: E. Raymond Hall, Chairman, Henry S. Fitch, Frank B. Cross

Volume 17, No. 12, pp. 517 557, 4 pls. 9 figs. Published March 20, 1968

University of Kansas Lawrence, Kansas

PRINTED BY ROBERT R. (BOB) SANDERS, STATE PRINTER TOPEKA, KANSAS 1968

31 9419

Middle American Frogs of the Hyla microcephala Group

BY WILLIAM E. DUELLMAN AND M. J. FOUQUETTE, JR.

CONTENTS

PAGE

Introduction 519 Acknowledgments 520 Materials and Methods 520

Hyla microcephala Group 521 Key to Species and Subspecies 522

Accounts of Species and Subspecies 523

Cranial Osteology 540

Analysis of Mating Calls 544

Life History 550

Phylogenetic Relationships 552

Literature Cited 556

INTRODUCTION

The small yellow tree frogs, Hyla microcephala and its relatives, are among the most frequently heard and commonly collected frogs in the lowlands of southern México and Central America. The similarities in size, proportions, and coloration of the different species have resulted not so much in a multiplicity of specific names, but in differences of opinion on the application of existing names to the various taxa. For example, the populations on the Atlantic lowlands have been known by three names, two of which have been applied to other taxa. Much of the confusion has been the result of previous workers' unfamiliarity with the animals in life and unawareness of the intraspecific geographic variation in the most widespread species.

Independently we undertook studies of these frogs in the field. The second author worked on the interspecific relationships and isolating mechanisms in Panamá (Fouquette, 1960b) and later studied the species in southern México. As part of his survey of the hylids of Middle America, the first author accumulated field and laboratory data on the frogs throughout their ranges in México and Central America. The purpose of this report is to present our findings on the four species of Middle American frogs that we place in the Hyla microcephala group. In addition to conventional taxonomic characters, we have utilized the features of the cranial osteology and have relied heavily on the data obtained from an analysis of the mating calls. Furthermore, we have included ecological and distributional data in our synthesis of interspecific relationships.

ACKNOWLEDGMENTS

Examination of specimens was made possible by the provision of working space at various institutions or through the loan of specimens. For their generosity in this manner we are grateful to Richard J. Baldauf, Charles M. Bogert, James E. Böhlke, Doris M. Cochran, Robert F. Inger, John M. Legler, Alan E. Leviton, Gerald Raun, Jay M. Savage, Hobart M. Smith, Robert C. Stebbins, Wilmer W. Tanner, Charles F. Walker, Ernest E. Williams, and Richard G. Zweifel.