SYSTEMATICS, BIOSTRATIGRAPHY, AND PALEOBIOGEOGRAPHY OF EARLY MIOCENE ARTIODACTYLS FROM THE PANAMA CANAL, PANAMA, CENTRAL AMERICA By ALDO FERNANDO RINCÓN A DISSERTATION PRESENTED TO THE GRADUATE SCHOOL OF THE UNIVERSITY OF FLORIDA IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE DEGREE OF DOCTOR IN GEOLOGY UNIVERSITY OF FLORIDA 2016 1 © 2016 Aldo Fernando Rincón 2 To my dear grandmother… 3 ACKNOWLEDGMENTS I thank Carlos A. Jaramillo at STRI and Camilo Montes at Universidad de Los Andes for all these years of support and advice; to my advisor (Jonathan I. Bloch) for everything he has done for my professional development; to the additional members of my Research Committee (Bruce J. MacFadden, David A. Foster, Richard C. Hulbert Jr., and David W. Steadman) for help with anatomical terminology, taxonomic nomenclature, and academic support. Special thanks to Richard Hulbert Jr., David Steadman, and Jason R. Bourque for their moral support during the preparation of the final document and, in general, during my attendance to graduate school. Jason R. Bourque, Rachell Narducci, and Dawn Mitchell at FLMNH, who prepared the specimens in the laboratory. Sandra Suarez, Maria C. Vallejo, and Federico Moreno (STRI); Jorge Moreno-Bernal, Cristina Byrd, Alan Bouché, Silvia Ascari, Katy. Cummings, Aaron. R. Wood, and Chris Ward (PCP-PIRE) who helped in the collection of the specimens. I thank the Panama Canal Authority (ACP) for access to relevant fossil sites. I specially thank to Pamela Haines, John Jaeger and Raymond Russo in the Department of Geological Sciences at the University of Florida for all their help during the Graduate Program. This research was supported by UF Research Opportunity Grant; the U.S. National Science Foundation Partnerships in International Research and Education grant 0966884 (OISE, EAR, DRL), EAR 0824299, and EAR 0418042; funds from the Florida Museum of Natural History; University of Florida, Department of Geology; STRI- Tupper Paleontological Fund; STRI-Panama Canal Authority Fund; and Ricardo Perez Toyota, Panama. 4 TABLE OF CONTENTS page ACKNOWLEDGMENTS .................................................................................................. 4 LIST OF TABLES ............................................................................................................ 8 LIST OF FIGURES ........................................................................................................ 10 ABSTRACT ................................................................................................................... 13 CHAPTER 1 INTRODUCTION .................................................................................................... 15 Conventions ............................................................................................................ 21 Institutional Abbreviations ....................................................................................... 22 Geological Setting ................................................................................................... 23 Biostratigraphy of Early Miocene Terrestrial Mammals from Panama .................... 27 2 EARLY MIOCENE FOSSIL PROTOCERATIDS (PROTOCERATINAE) FROM PANAMA ................................................................................................................. 32 Systematic Paleontology ......................................................................................... 37 Paratoceras aff. P. tedfordi ............................................................................... 39 Description ................................................................................................. 39 Discussion and Comparisons ..................................................................... 42 Paratoceras orarius sp. nov. ............................................................................. 43 Description ................................................................................................. 44 Discussion and Comparisons ..................................................................... 46 Paratoceras coatesi sp. nov. ............................................................................ 47 Description ................................................................................................. 49 Discussion and Comparisons ..................................................................... 56 Phylogenetic Analysis ............................................................................................. 58 Discussion .............................................................................................................. 60 3 EARLY MIOCENE FLORIDATRAGULINE CAMELS FROM PANAMA .................. 81 Systematic Paleontology ......................................................................................... 89 Aguascalientia panamaensis Rincón et al., 2012 ............................................. 90 Description ................................................................................................. 92 Discussion and Comparisons ..................................................................... 94 Floridatragulus sp. nov. .................................................................................... 96 Description ................................................................................................. 97 Discussion and Comparisons ................................................................... 103 Floridatragulinae, gen. nov. ............................................................................ 107 5 Floridatragulinae gen. et. sp. nov. .................................................................. 108 Description ............................................................................................... 109 Comparisons ............................................................................................ 116 Discussion................................................................................................ 120 Phylogenetic Analysis ........................................................................................... 122 Late Oligocene to Early Miocene Higher Camelid Paleobiogeography in Southern North America .................................................................................... 126 Discussion ............................................................................................................ 129 4 EARLY MIOCENE TAYASSUIDS FROM PANAMA ............................................. 152 Systematic Paleontology ....................................................................................... 164 Hesperhyinae, gen. et. sp. nov. ...................................................................... 164 Hesperhyinae n. gen. A & sp. A. .................................................................... 165 Description ............................................................................................... 166 Comparisons ............................................................................................ 171 Hesperhyinae n. gen. A & sp. B ..................................................................... 173 Description ............................................................................................... 174 Comparisons ............................................................................................ 180 Floridachoerus White, 1941 ............................................................................ 184 Description ............................................................................................... 185 Discussion................................................................................................ 186 Hesperhyinae n. gen. B. ................................................................................. 186 Hesperhyinae n. gen. B & sp. A ..................................................................... 187 Description ............................................................................................... 188 Comparisons ............................................................................................ 191 Phylogenetic Analysis ........................................................................................... 194 Discussion ............................................................................................................ 197 5 ARTIODACTYL FAUNAL COMPOSITION AND PALEOECOLOGY .................... 218 6 CONCLUSIONS ................................................................................................... 243 APPENDIX A DENTAL MEASUREMENTS OF PROTOCERATINES FROM THE EARLY MIOCENE FROM PANAMA ................................................................................. 251 B DENTAL CHARACTERS USED IN THE PHYLOGENETIC ANALYSIS OF PROTOCERATINAE (CHAPTER 2). ALL CHARACTERS ARE TREATED AS UNORDERED. ...................................................................................................... 257 C CHARACTER-TAXON MATRIX USED IN PHYLOGENETIC ANALYSES OF PROTOCERATIDAE (CHAPTER 2). SEE APPENDIX B FOR CHARACTER DESCRIPTIONS ................................................................................................... 259 D DENTAL MEASUREMENTS OF EARLY MIOCENE CAMELIDS FROM SUBTROPICAL AND TROPICAL ASSEMBLAGES FROM NORTH AMERICA. .. 260 6 E DESCRIPTION OF DENTAL CHARACTERS USED IN THE PHYLOGENETIC ANALYSIS OF EARLY MIOCENE CAMELIDAE (CHAPTER 3). ALL CHARACTERS TREATED AS UNORDERED. ....................................................