Phylogenetic studies of mimetic tiger moths based on morphological and molecular data (Lepidoptera:Arctiidae:Euchromiini)

This dissertation project was designed with three separate, but related studies. The first chapter is a molecular survey of the tribes Ctenuchini and Euchromiini (Lepidoptera: Arctiidae). This chapter also examines the use of and characteristics of the mitochondrial gene, cytochrome-b. Cytochrome-b had the similar characteristics as another mitochondrial gene, COI, but was less useful for recovering intergeneric relationships. The total evidence tree casts doubt on the traditional taxonomy of the group. For the Class Insecta, we found that functional conservation of amino acids occurs for the same regions as found in vertebrates with the exception of lice. Lice have an accelerated rates of non-synonymous substitutions. Accelerated rate of cyt-b nucleotide and amino acid evolution in bees may be correlated with increased metabolism associated with facultative endothermy (=heterothermy).; In Chapter two, I present a taxonomic history of genera in the Sphecosoma group. I also describe choice of outgroups and character systems used, both traditional and novel. I examined 61 of the 89 species described in the Sphecosoma generic group (Lepidoptera: Arctiidae), and 13 species in seven outgroup genera. Cladistic analyses were performed using additive and nonadditive starting points for transformation series analysis. A revised classification was based on concordance between five sets of analyses. My classification of the Sphecosoma generic group includes five genera and two species groups. I propose six generic synonyms, and 22 new combinations.; The Sphecosoma generic group represent an excellent system for examining the evolution of mimicry. Mimicry has been examined in field studies, behavioral studies, and computer simulations; however, phylogenetic studies examining the evolution of mimicry are rare. This study examines a phylogeny of the Sphecosoma generic group, to test hypotheses of conventional Müllerian mimicry versus quasi-Batesian mimicry. A phylogeny of these mimics reveals that mimetic type is more phylogenetically conserved than would be expected by chance alone. Additionally, individual mimetic characters are also conserved. The observed phylogeny is also more similar to a Müllerian scenario than that of a quasi-Batesian scenario.