Dissertation Research: Phylogenetic Analysis of the Dytiscinae (Coleoptera: Dytiscidae) as Inferred from Morphological and Molecular Characters

Cornell Univ - State: Awds Made Prior May 2010, Ithaca NY

Investigators

Abstract

0073088 Wheeler and Miller Graduate student Kelly Miller, under the direction of Dr. Quentin Wheeler, is studying the systematics and natural history of beetles of the subfamily Dytiscinae. The result of this project will be an understanding of the phylogeny of dytiscine beetles (Coleoptera: family Dytiscidae), an important group of large, aquatic predators. These diving beetles occur in lakes and ponds throughout the world and are important predators of aquatic insects, such as mosquitoes, as well as a variety of other prey items including small vertebrates such as tadpoles and fish fry. Members of the group have interesting ecological properties as dominant predators as well as interesting behavioral properties, such as complex mating behaviors. This project will focus on discovering the phylogenetic relationships between the higher taxonomic groups in this subfamily including the currently recognized five tribes and 25 or so genera. It will also include members of the other major subfamilies of diving beetles as outgroup taxa which will help establish a phylogeny for the entire family. The classification based on this analysis will be one of the first for any group of dytiscids that is based upon an explicit and comprehensive phylogenetic analysis. The project will be based on morphological characters observed from adult and immature forms, and on molecular sequence data for the nuclear gene "wingless" and the mitochondrial gene for cytochrome-B, sampled from as many lineages as possible within Dytiscinae and relevant outgroup taxa. Newly collected material from South America and Australia will augment North American collections and museum specimens. These data will be analyzed in a variety of ways, but eventually all available data will be combined to discover the best-supported hypothesis of the evolutionary history of the group. The resulting phylogenetic hypothesis for the subfamily will form the basis for a revised classification that is stable and optimally informative. As a result of this project, biologists using dytiscine beetles to answer questions about ecology, behavior, biogeography, etc., will be able to make informed decisions about suitable study taxa based on phylogenetic criteria. This will, in turn, provide greater insight into generalizations about the process of evolution.