Produced by Chris Curnow, Joseph Cooper and the Online Distributed Proofreading Team at https://www.pgdp.net UNIVERSITY OF KANSAS PUBLICATIONS MUSEUM OF NATURAL HISTORY Volume 18, No. 6, pp. 505-545, 7 figs., 4 pls. December 2, 1969 The Systematics of the Frogs of the _Hyla rubra_ Group in Middle America BY JUAN R. LEÓN University of Kansas Lawrence 1969 UNIVERSITY OF KANSAS PUBLICATIONS, MUSEUM OF NATURAL HISTORY Editors: Frank B. Cross, Philip S. Humphrey, Robert M. Mengel. Volume 18, No. 6, pp. 505-545, 7 figs., 4 pls. Published December 2, 1969 UNIVERSITY OF KANSAS Lawrence, Kansas PRINTED BY ROBERT R. (BOB) SANDERS, STATE PRINTER TOPEKA, KANSAS 1969 The Systematics of the Frogs of the _Hyla rubra_ Group in Middle America BY JUAN R. LEÓN CONTENTS PAGE INTRODUCTION 508 Acknowledgments 508 Materials and Methods 509 THE HYLA RUBRA GROUP 509 Key to Species and Subspecies 510 Key to Known Tadpoles 511 ACCOUNTS OF SPECIES AND SUBSPECIES 511 _Hyla boulengeri_ (Cope) 511 _Hyla foliamorta_ Fouquette 520 _Hyla rubra_ Laurenti 524 _Hyla elaeochroa_ Cope 525 _Hyla staufferi_ Cope 532 _Hyla staufferi staufferi_ Cope 537 _Hyla staufferi altae_ Dunn 540 EVOLUTIONARY HISTORY 540 LITERATURE CITED 543 INTRODUCTION The tree frogs of the _Hyla rubra_ group are abundant and form a conspicuous element of the Neotropical frog fauna. Representatives of the group occur from lowland México to Argentina; the greatest diversity is reached in the lowlands of southeastern Brazil (Cochran, 1955). The group apparently originated in South America; the endemic Central American species evolved from stocks that invaded Middle America after the closure of the Colombian Portal in the late Pliocene.