AN ABSTRACT OF THE DISSERTATION OF Scott J. Fitzgerald for the degree of Doctor of Philosophy in Entomology presented on 3 June, 2004. Title: Evolution and Classification of Bibionidae (Diptera: Bibionomorpha). Abstract approved: Signature redacted forprivacy. p 1ff Darlene D. Judd The family Bibionidae has a worldwide distribution and includes approximately 700 species in eight extant genera. Recent studies have not produced compelling evidence supporting Bibionidae as a monophyletic group or identified the sister group to bibionids. Therefore, the purpose of this study is to examine the classification and evolution of the family Bibionidae in a cladistic framework. The study has four primary objectives: 1) test the monophyly of the family; 2) determine the sister group of Bibionidae; 3) examine generic and subfamilial relationships within the family; and 4) provide a taxonomic revision of the extant and fossil genera of Bibionidae. Cladistic methodology was employed and 212 morphological characters were developed from all life stages (adult, pupa, larva, and egg). Characters were coded as binary or multistate and considered equally weighted and unordered. A heuristic search with a multiple random taxon addition sequence was used and Bremer support values are provided to show relative branch support. A strict consensus of 43 equal-length trees of 1,106 steps indicates that the family Bibionidae is monophyletic and is sister group to Pachyneuridae. All bibionid genera are supported as monophyletic except for Bibio and Bibiodes (monophyly of the latter genus was not examined because only one exemplar was included). Results indicate that the subfamilies Hesperininae and Bibioninae are monophyletic and Pleciinae is paraphyletic. The cladistic structure of the family is Hesperinus + (Penthetria + (Plecia + (Dilophus + Bibionini))) and relationships between the four genera of tribe Bibionini are unresolved. Eleven genera of Bibionidae are recognized in the generic revision; eight extant genera and three fossil genera. The three fossil genera, Fushunoplecia Hong, Clothonopsis Hong & Wang, and Megeana Meunier were not available for study and thus the status of these taxa and their placement within Bibionidae is unresolved. The extant genera are: Hesperinus Walker, Penthetria Meigen, Plecia Wiedemann, Bibio Geoffroy, Bibiodes Coquillett, Bibionellus Edwards, Enicoscolus Hardy, and Dilophus Meigen. A diagnosis and descriptions of all available life stages are provided for each of these genera. Additionally, several new generic synonyms are proposed. The fossil genus Bibiopsis Heer is treated as junior synonym of Penthetria. The fossil genus Epiplecia Giard and the extant subgenera Heteroplecia Hardy and Pleciodes Hardy are treated as junior synonyms of Plecia. The fossil genus Lithosomyia Carpenter is a junior synonym of Bibio, and the fossil genus Bibiodites Cockerell is a junior synonym of Bibiodes. Two genera previously included in the family Bibionidae are removed from the family. The fossil genus Mesopleciella Rohdendorf belongs in the extinct family Protopleciidae and the family placement of the fossil genus Longicornia could not be determined, but is not a bibionid. Evolution and Classification of Bibionidae (Diptera: Bibionomorpha) by Scott J. Fitzgerald A DISSERTATION submitted to Oregon State University in partial fulfillment of the requirements for the degree of Doctor of Philosophy Presented June 3, 2004 Conmiencement June 2005 ACKNOWLEDGEMENTS I would like to thank all the members of my committee for their guidance and patience: Darlene Judd, Andy Brower, Monty Wood, Joey Spatafora, and Ken Funk. A special thank you to Darlene whose expectations were higher than my own; this kept me continually striving for something better. Thanks also to Andy Brower for igniting my interest in the philosophical underpinnings of science. Deep gratitude is due to my wife Julie for her endless support and encouragement. She kept me emotionally balanced, well fed, and helped me keep things in perspective when I felt overwhelmed. Special thanks to my lab mates and departmental friends who are co-survivors of the dissolution of the Department formerly known as Entomology. These folks provided technical advice, snacks, and the necessary comradeship that kept me laughing amidst departmental chaos and the rise of the Bush regime. Thank you also to an entire community of curators and dipterists, many of whom are listed in the methods section. These people loaned and donated specimens, discussed characters, sent me reprints, and pointed me in this or that direction to help me answer my questions. This study could not have been completed without the hard work of the interlibrary loan staff at OSU. Thank you. I would also like to acknowledge a NSF Dissertation Improvement Grant to Judd and Fitzgerald, a NSF Career Grant to Judd (DEB 0093392), and the Harold and Leona Rice Endowment for Systematic Entomology for partial support of this research. TABLE OF CONTENTS Page Introduction 1 Past and Present Classification 3 Higher level classification - Nematocera and Bibionomorpha .3 Putative sister groups of Bibionidae 5 Monophyly of Bibionidae 11 Classification of extant Bibionidae into subfamilies 12 Generic relationships ...14 Bibionid Biology, Distribution, & Diversification ..15 Biology 15 Distribution and diversification 17 Materials and Methods . ..20 Taxon sampling 20 Species concepts .23 Specimens 24 Collecting and rearing ..27 Homology 28 Character systems .29 Cladistic methods .30 TABLE OF CONTENTS (Continued) Page Phylogenetic Results 33 Monophyly of Bibionidae and its sister group 37 Subfamilies of Bibionidae 38 Genera of Bibionidae 39 Species-level relationships .40 Outgroups, Bibionomorpha, and higher classification 41 Pachyneundae ..41 Sciaroidea 42 Bibionomorpha sensu stricto 42 Neodiptera and the sister group to Brachycera 43 Axymyiidae ..44 Comparison of results to previous studies of Bibionidae 44 Pinto & Amorim (2000) 44 Skartveit & Willassen (1996) 45 Blaschke-Berthold (1994) 45 Successive approximations weighting (SAW) .46 Character Homology and Variation .47 Head .47 Thorax ..60 Legs ..72 Wing .83 The radial field .92 The medial, cubital, and anal fields ..102 TABLE OF CONTENTS (Continued) Page Abdomen ..109 Male terminalia .113 Pre-genital segments 119 Epandrium 120 Hypandrium and gonocoxites 126 Proctiger 134 Parameres and dorsal bridge 137 Sperm pump .162 Rotation and flexation ..183 Female terminalia & egg ...185 Larva ..190 Body (general) ...191 Segmentation 199 Spiracles .203 Head (general) ..208 Labium, hypopharynx, and associated structures .220 Cardo and maxilla . ..241 Mandible 248 Epipharynx and associated structures 251 Pupa 254 Generic Revision 258 Family Bibionidae .259 Genus Hesperinus Walker .259 Genus Penthetria Meigen ..265 Genus Plecia Wiedemann .273 Genus Bibio Geoffroy 282 Genus Bibiodes Coquillett 291 Genus Bibionellus Edwards ..295 Genus Enicoscolus Hardy .299 Genus Dilophus Meigen 303 Genus Fushunoplecia Hong 309 TABLE OF CONTENTS (Continued) Page Genus Clothonopsis Hong & Wang ..310 Genus Megeana Meunier . ..311 Genera removed from Bibionidae .312 Genus Mesopleciella Rohdendorf .312 Genus Longicornia Hong ..313 Conclusion .314 Bibliography 316 Appendices 364 Appendix I - Abbreviations used in figures . ..365 Appendix Rearing notes .369 Appendix III - Character state changes by node 373 Appendix P1 - Data matrix 377 LIST OF FIGURES Figure Page Interpretation of previous phylogenetic hypotheses of infraorder Bibionomorpha 4 Strict consensus tree from 43 cladograms of 1,106 steps 34 One of 43 cladograms of 1,106 steps 35 Bremer support 36 Adult head I .56 Adult head II ...57 Adult thorax of Bibionidae 63 Legs I (Bibionidae) ..77 Legs II .78 Wingsl ..86 Possible transition series resulting in venation of Cramptonomyiinae (Pachyneuridae) 87 Wings II 88 Wings III 89 WingsW 90 Male terminalia of Bibionidae I 116 Male terminalia of Bibionidae II 118 Tipulidae and Axymyiidae, sperm pump .150 Trichocera tetonensis Alexander (Trichoceridae), male terminalia, internal .152 LIST OF FIGUIRES (Continued) Figure Page Scatopse notata (L.)(Scatopsidae), sperm pump .154 Arthria analis Kirby (Scatopsidae), sperm pump 155 Sylvicola cinctus (Fab.)(Anisopodidae), male terminalia, internal 156 Hesperinus brevfrons Walker (Bibionidae), male terminalia, internal ..158 Plecia nearctica Hardy (Bibionidae), parameres and sperm pump 159 Bibio albiennis Say (Bibionidae), parameres and sperm pump .160 Cramptonomyia spenceri Alexander (Pachyneuridae), parameres and sperm pump, ventral 161 Female terminalia and eggs of Bibionidae .187 Larval habitus .193 Larva, general I 194 Larva, general II .196 Larval head .215 Larval head and antennae 217 Anisopodidae and Axymyiidae, larval mouthparts, ventral .. ..225 Sciaroidea, larval mouthparts, ventral 227 Pachyneuridae, larval labium and maxilla, ventral .229 Larval labiohypopharynx 231 Hesperinus and Penthetria (Bibionidae), larval labium and maxilla, ventral . ..233 LIST OF FIGURES (Continued) Figure Page Bibio albipennis Say (Bibionidae), larval labiohypopharynx and maxilla, ventral 235 Plecia (Bibionidae), larval labiohypopharynx and maxilla, ventral 236 LIST OF TABLES Table Page Classifications of Bibionidae as treated by McAtee (1921), Hardy and Takahashi (1960), Krivosheina (1986, 1997b), Wood and Borkent (1989), and Pinto and Amorim (2000) 13 Number of bibionid species by genus and biogeographic region 19 Exemplars of Bibionidae included in the analysis ..21 Outgroup exemplars included