Phylogeny, chaetotaxy, and ecology of the Onthophilinae and Tribalinae (Coleoptera: Histerdae)

Chapter I. Both instars of the relatively generalized histerid, Onthophilus nodatus LeConte, are described and illustrated. This is the first larval description for the genus Onthophilus and the first study of chaetotaxy of histerid larvae. Setae of the thorax and abdomen were serially homologized to develop a setal nomenclatural system for the first instar. This system is easily applied to other histerid genera.;Chapter II. A setal nomenclatural system is developed for histerid pupae. This is the first study of the chaetotaxy of histerid pupae and the first pupal description for the genus Onthophilus Leach. Some plasticity was detected in the setal distribution pattern of histerid pupae necessitating caution in generalizing pupal character information.;Chapter III. The duration of all sub-imaginal stages of Epierus divisus Marseul was determined. This is the first developmental study for Epierus. Developmental rates of the subcortical Epierus divisus were compared directly to the dung/carrion-associated Euspilotus assimilis (Paykull) and found to be significantly longer for all developmental stages. Developmental rates of Epierus divisus were also compared to developmental rates reported in the literature for other species of histerids that develop in association with ephemeral systems.;Chapter IV. A phylogenetic analysis is presented for the World genera of Onthophilinae and Tribalinae (Coleoptera: Histeridae). The Onthophilinae includes six genera, Onthophilus Leach, Vuattouxinus Threond, Epiechinus Lewis, Australepierus new genus, Plagiogramma Tarsia in Curia, and Epierus Erichson. The Tribalinae includes seven genera are recognized and assigned to two tribes: Tribalini Bickhardt, 1917, including Stictostix Marseul, Peploglyptus LeConte, Tribalus Erichson Eutribalus Bickhardt, Parepierus Bickhardt, new status, Paridolia new genus, and Idolia Lewis. Glymma Marseul, Sculptura Threond, and Sigillum Therond are synonymized with Epiechinus. Pseudepierus Casey is synonymized with Plagiogramma. Caerosternus LeConte and Tribalasia Cooman are synonymized with Eutribalus. Scaphidister Cooman is synonymized with Parepierus. Spaericosoma Marseul is excluded from the Onthophilinae and Tribalinae. A key to the word genera is provided.;Chapter V. Both instars and pupae of Idolia gibba Lewis, and Eutribalus americanus are described and illustrated. These are the first larval and pupal description for the Idolia genus group. A key is provided to distinguish larvae and pupae of these genera.