PHYLOGENY AND BIOGEOGRAPHY OF THE MAYFLY FAMILY LEPTOHYPHIDAE (INSECTA: EPHEMEROPTERA) WITH A TAXONOMIC REVISION OF SELECTED GENERA A Dissertation by DAVID EUGENE BAUMGARDNER Submitted to the Office of Graduate Studies of Texas A&M University in partial fulfillment of the requirements for the degree of DOCTOR OF PHILOSOPHY August 2008 Major Subject: Entomology PHYLOGENY AND BIOGEOGRAPHY OF THE MAYFLY FAMILY LEPTOHYPHIDAE (INSECTA: EPHEMEROPTERA) WITH A TAXONOMIC REVISION OF SELECTED GENERA A Dissertation by DAVID EUGENE BAUMGARDNER Submitted to the Office of Graduate Studies of Texas A&M University in partial fulfillment of the requirements for the degree of DOCTOR OF PHILOSOPHY Approved by: Chair of Committee, John D. Oswald Committee Members, Jimmy K. Olson Merrill H. Sweet James B. Woolley Head of Department, Kevin M. Heinz August 2008 Major Subject: Entomology iii ABSTRACT Phylogeny and Biogeography of the Mayfly Family Leptohyphidae (Insecta: Ephemeroptera) with a Taxonomic Revision of Selected Genera. (August 2008) David Eugene Baumgardner, B.S., Baylor University; M.S., University of North Texas Chair of Advisory Committee: Dr. John D. Oswald A cladistic analysis of the world genera of the mayfly family Leptohyphidae is presented. Analyses of a matrix of 58 ingroup and 9 outgroup species and 119 morphological characters strongly supports the monophyly of Leptohyphidae and its sister-group relationship with Coryphoridae. Larval and adult taxonomic keys are provided to the 11 recognized extant genera. A synonymical listing, differential diagnosis, list of proposed synapomorphies, diagnostic illustrations, and notes on distribution and included species are given for each genus. The following new synonyms of genus Tricorythodes are proposed: Ableptemetes n. syn., Cabecar n. syn., Epiphrades n. syn., Homoleptohyphes n. syn., Macunahyphes n. syn., Tricoryhyphes n. syn. The former genus Asioplax is newly regarded as a subgenus of Tricorythodes. A species-level revision of North and Central American Leptohyphes is presented. A key to the 15 Leptohyphes species known as larvae is provided. In addition, detailed descriptions, diagnosis, and geographic distributions are given for all species of Leptohyphes known from North and Central America. Biogeographic analysis suggests that the family Leptohyphidae originated in South America, and that its North American iv species are the descendants of one or more ancestral species that crossed northward over the Panamanian land bridge. The results of this research clearly show that the mayfly family Leptohyphidae is a strongly supported monophyletic clade supported by five unique synapomorphies. Currently recognized genera are also strongly supported; however, little support was found for subfamilies. The sister family is clearly Coryphoridae, which is supported by three unique synapomorphies. Biogeographic analysis indicates that Leptohyphidae originated in South American, with at least five independent invasions from South America to North and Central America during the evolution of Leptohyphidae. v DEDICATION This work is dedicated to two eminent ephemeropteran systematists who passed away during the course of this research, Dr. George F. Edmunds, Jr. and Dr. William L. Peters. Both will be greatly missed by their many friends, associates, and students. They were not only leaders in their field but were outstanding individuals who contributed much to our knowledge of the world around us. Dr. George F. Edmunds, Jr. (April 28, 1920 – March 04, 2006), whose career spanned more than 50 years, is generally considered the Father of North American ephemeropterology research. Dr. Edmunds completed his Ph.D. at the University of Massachusetts, under the guidance of Dr. Jay Traver. Dr. Edmunds began his teaching and research career at the University of Utah and retired from that university in 1989 as a professor of Biology. During his years in Utah, he was associated with research programs throughout the world, and was regarded by many mayfly specialists as the most influential ephemeropterist of his generation. Dr. William L. Peters (27 June 1939 – 03 June 2000) was a student of Dr. Edmunds who had a long and successful career at Florida A&M University, Gainesville, where he made major contributions to the study of the Ephemeroptera. His scientific research focused on the cosmopolitan mayfly family Leptophlebiidae. Dr. Peters published more than 100 scientific papers and monographs, and established more than 60 new genera, subgenera, and species (Hubbard, 2003). He also encouraged, guided, and collaborated with many mayfly researchers throughout the world. vi ACKNOWLEDGMENTS Most systematists recognize the substantial sacrifices and contributions that their families make in support of their research. While we travel throughout the world in search of our critters and spend hours upon hours in the laboratory, our loved ones wait patiently. First, I would like to thank my wife, Abigail, for the many hours, days, weeks, months and years that she has endured my study and research. Her support, whether in the field, laboratory, or at home is always appreciated. Her patience has no bounds. And to my son Kirk, for all his support, understanding, and assistance on more than one field trip. No graduate student would be able to complete their research without the constant oversight, support, and harassment of their committee. Drs. John D. Oswald, James B. Woolley, Jimmy K. Olson, and Merrill H. Sweet constantly supported and pushed me to be the best systematist possible. Their patience and understanding was greatly appreciated, especially during the 15 months that I was absent from the university in support of Operation Iraqi Freedom I. Numerous friends and fellow scientists made substantial contributions to the completion of this research through their advice, time, and support. In particular, Mrs. Jan Peters and Dr. Wills Flowers (Florida A&M University) were a tremendous resource for discussing various aspects of ephemeropteran systematics, loaning specimens, and hosting me during visits to Florida A&M University. Dr. Carlos Molineri (Universidad Nacional de Tucumán, Tucumán, Argentina) provided a substantial number of South vii American leptohyphid specimens, which increased the depth and breadth of the study. Dr. Pat McCafferty (Purdue University) was of great assistance in discussing various aspects of ephemeropteran systematics. Drs. Jack Schuster (Universidad del Valle, Guatemala City, Guatemala) and Jean-Michel Maes (Museo Entomologico, Leon, Nicaragua) were of tremendous assistance during collecting trips to Guatemala and Nicaragua, respectively, where they arranged for permits, lodging, and guidance. The administrative assistance and support of the Instituto Nacional de Biodiversidad (Santo Domingo de Heredia, Costa Rica) while working in Costa Rica is also much appreciated. The donations of Cuban leptohyphid mayflies by Dr. Nikita Kluge (St. Petersburg State University, St. Petersburg, Russia) was greatly appreciated. Loans from the California Academy of Sciences and Academy of Natural Sciences of Philadelphia were particularly significant for providing many type specimens and much additional study material. The tremendous curatorial support provided by Mr. Edward Riley (Texas A&M University) is greatly appreciated. And finally, the financial support of the Texas A&M University Entomology Graduate Student Organization, the L.T. Jordan Institute for International Awareness, and the Ernst Mayr Travel Grants in Animal Systematics from the Museum of Comparative Zoology, Harvard University, is gratefully acknowledged. viii TABLE OF CONTENTS Page ABSTRACT .............................................................................................................. iii DEDICATION ........................................................................................................... v ACKNOWLEDGMENTS ........................................................................................ vi TABLE OF CONTENTS .......................................................................................... viii CHAPTER I INTRODUCTION: BIOGEOGRAPHY ........................................... 1 Biogeography and the Panamanian Land Bridge ................... 1 Study Group ........................................................................... 5 Morphological Overview ....................................................... 6 II CLADISTIC ANALYSIS ................................................................... 11 Methods and Data .................................................................. 11 Characters .............................................................................. 15 Cladistic Results .................................................................... 70 Discussion ............................................................................. 73 III TAXONOMIC REVISION ................................................................ 81 Field Studies .......................................................................... 81 Museum and Laboratory Studies ........................................... 81 Taxonomic History and Early Classification ........................ 82 Family Leptohyphidae Landa and Soldán, 1985 ................... 85 Taxonomy .............................................................................. 86 Generic Treatments ............................................................... 89 Genus Leptohyphodes Ulmer, 1920 .......................................