The scarab beetle tribe Cyclocephalini (Coleoptera: Scarabaeidae: Dynastinae) includes 15 genera and approximately 500 species that are distributed primarily in the New World. Species in the group are important pollinators of aroids, palms, and lilies, some are agricultural pests, and a few are invasive in areas where they have been introduced. Evolutionary relationships of the group have not been examined, and monophyly of the tribe and relationships of genera have not been addressed. As a result, the classification remains unstable, and there is no foundation with which to interpret evolutionary patterns. To provide an evolutionary framework, a phylogenetic analysis using 77 adult morphological characters was performed. Representatives from all recognized cyclocephaline genera were examined as well as taxa that have historically been included in the tribe. Outgroups included exemplars from the dynastine tribes Oryctini, Oryctoderini, and Pentodontini and the ruteline tribes Anomalini and Rutelini. Based on the analysis, Cyclocephalini, as currently circumscribed, does not constitute a monophyletic lineage. Thus, the current classification does not reflect evolution, and revision is required. Based on strong character support, the genera Eriocelis and Stenocrates are not a part of the new cyclocephaline clade while genera Parapucaya and Neohyphus are members of the new Cyclocephalini.

Thesis (M.S.)--Wichita State University, College of Liberal Arts and Sciences, Dept. of Biological Sciences.