I NEW BAENID TURTLES from THE
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NEW BAENID TURTLES FROM THE CRETACEOUS KAIPAROWITS FORMATION OF SOUTHERN UTAH: IMPLICATIONS FOR LARAMIDIAN BIOGEOGRAPHY by Joshua Ryan Lively A thesis submitted to the faculty of The University of Utah in partial fulfillment of the requirements for the degree of Master of Science in Geology Department of Geology and Geophysics University of Utah August 2013 i Copyright © Joshua Ryan Lively 2013 All Rights Reserved i The University of Utah Graduate School STATEMENT OF THESIS APPROVAL The thesis of ____________________________________________________________Joshua Ryan Lively has been approved by the following supervisory committee members: November 2, _________________________________Randall B. Irmis ___________, Chair ________________2012 Date Approved November 2, ____________________________________________,Allan A. Ekdale Member ________________2012 Date Approved December 17, ____________________________________________,Dennis M. Bramble Member ________________2012 Date Approved and by _________________________________________________________,D. Kip Solomon Chair of the Department of ________________________________________________________Geology and Geophysics and by Donna M. White, Interim Dean of The Graduate School. ii ABSTRACT Recent discoveries demonstrate that Campanian dinosaur assemblages across the western North American subcontinent (Laramidia) exhibit basin-scale endemism, with each sedimentary basin possessing its own unique assemblage, and an apparent higher- level biogeographic boundary between northern and southern Laramidia. Subsequently, during the Maastrichtian, most taxa are present in multiple basins, with some forms supporting the presence of distinct northern/southern provinces, whereas others are more cosmopolitan. Despite these dinosaur biogeographic data, little attention has been paid to other vertebrate groups. To test these biogeographic hypotheses, I examined the alpha taxonomy, evolution, and paleobiogeography of the paracryptodiran turtle clade Baenidae using a newly-generated species-level phylogeny. Baenids were one of the most diverse and abundant turtle clades during the Late Cretaceous, are restricted to North America, and have a well-sampled fossil record, making them an ideal study system for examining Laramidian biogeography. I first assessed the taxonomic affinities of newly discovered baenid turtles from the Upper Cretaceous (Campanian) Kaiparowits Formation of southern Utah. I found that at least five distinct baenid species inhabited the Kaiparowits Basin during the Campanian. These taxa include Denazinemys nodosa, previously known from Texas and New Mexico, Boremys grandis, previously known from New Mexico only, and three new iii taxa that appear to have been endemic to southern Utah. These newly described taxa include two new species of Neurankylus and a morphologically unique pig-nosed taxon. Using new morphologic data from the Kaiparowits specimens, I conducted a comprehensive phylogenetic analysis on the clade, utilizing 106 characters and 32 ingroup taxa. Based on occurrences alone, Campanian baenid assemblages display distinct northern and southern provinces with no taxonomic overlap. To investigate the evolutionary patterns of this biogeographic signal, I applied a dispersal-extinction- cladogenesis model to the strict consensus tree and three randomly selected most parsimonious trees from my phylogenetic analysis. This study reveals that the ancestral ranges for basal baenid branches were cosmopolitan across either Laramidia or all of North America. More derived baenids (i.e., subclade Baenodda) possessed ancestral ranges in the area of Montana, Wyoming, and the Dakotas, and the analysis reconstructs multiple individual lineages then dispersing to southern Laramidia and Alberta. iv TABLE OF CONTENTS ABSTRACT .................................................................................................................... iii LIST OF FIGURES .......................................................................................................... vii ACKNOWLEDGEMENTS ............................................................................................... ix CHAPTER 1: A PIG-NOSED BAENID TURTLE FROM THE KAIPAROWITS FORMATION (UPPER CRETACEOUS: CAMPANIAN) OF SOUTHERN UTAH ................................1 Abstract ....................................................................................................................1 Introduction ..............................................................................................................2 Institutional Abbreviations.......................................................................................4 Geologic Setting.......................................................................................................4 Methods....................................................................................................................6 Systematic Paleontology ..........................................................................................7 Description ...............................................................................................................9 Phylogenetic Analysis ............................................................................................31 Discussion ..............................................................................................................34 Conclusions ............................................................................................................38 2: BAENID TURTLES OF THE KAIPAROWITS FORMATION (UPPER CRETACEOUS: CAMPANIAN) OF SOUTHERN UTAH ..............................39 Abstract ..................................................................................................................39 Introduction ............................................................................................................40 Institutional Abbreviations.....................................................................................42 Geologic Setting.....................................................................................................43 Systematic Paleontology ........................................................................................44 Neurankylus sp. nov. A ..............................................................................46 Neurankylus sp. nov. B ..............................................................................56 New pig-nosed taxon .................................................................................62 Denazinemys nodosa ..................................................................................66 Boremys grandis ........................................................................................86 Discussion ..............................................................................................................93 Conclusions ............................................................................................................96 v 3: TESTING LARAMIDIAN PALEOBIOGOEGRAPHIC HYPOTHESES: EVIDENCE FROM THE EVOLUTION OF BAENID TURTLES ......97 Abstract ..................................................................................................................97 Introduction ............................................................................................................98 Phylogenetic Analysis ..........................................................................................101 Paleobiogeographic Analysis ...............................................................................128 Discussion ............................................................................................................144 Conclusions ..........................................................................................................147 APPENDICES A: LIST OF SPECIMENS USED ...................................................................................149 B: LIST OF CHARACTER USED IN PHYLOGENETIC ANALYSIS ........................154 C: CHARACTER-TAXON MATRIX ............................................................................165 D: TEMPORAL AND GEOGRAPHIC RANGES..........................................................175 E: GEOGRAPHIC DISPERSAL CONSTRAINTS ........................................................177 F: DISPERSAL-EXTINCTION-CLADOGENEIS RESULTS .......................................179 G: MEASUREMENTS ....................................................................................................199 REFERENCES ................................................................................................................203 vi LIST OF FIGURES FIGURE PAGE 1.1 Photographs of cranium, mandible, atlas, and axis of holotype specimen ............11 1.2 Three-dimensional reconstruction of the cranium of the holotype specimen ........12 1.3 Three-dimensional reconstruction of the mandible of the holotype ......................19 1.4 Carapace photographs and line drawings ..............................................................21 1.5 Plastron photographs and line drawings ................................................................22 1.6 Photograph and line drawing of the right forelimb ................................................29 1.7 Photograph and line drawing of the partial right pes .............................................32 2.1 Neurankylus sp. nov. A holotype carapace and plastron .......................................48 2.2 Postcranial elements of Neurankylus sp.