Phylogenetic relationships of the Euchromiine tiger moths

Members of Euchromiina and Ctenuchina are known for their ability to mimic other organisms and for their aposematism. Their overall appearance signals predators of their unpalatability due to larval sequestration of plant secondary chemicals; these moths are often members of Müllerian mimicry rings with other noxious insects. Because mimetic traits can be due convergence on common model species, evolutionary relationships within euchromiines are obscured, impeding an understanding of how mimetic traits were acquired in this lineage. Wing patterns represent a suite of traits that are instrumental to euchromiine mimicry. Wings can be hyaline (=clear), partially scaled, and scaled. Tiger moth wings display wing pattern elements that enhance their resemblance to other members of their mimicry rings. This research focuses on the following wing elements, Basalis (B), Discalis I (DI), Discalis II (DII), Externae patterns (E), and Apical spots. A phylogeny of 81 species (50 genera) was constructed using seven molecular markers (~ 4000 bp) with model-based approaches. Ancestral state reconstruction was assessed with Mesquite using stochastic models. Results indicate that the Euchromiina and Ctenuchina are monophyletic with respect to each other; with a misplaced ctenuchine genus Abrochia. Wing patterns do not appear to be conserved throughout the mimetic tiger moth lineage; indicating independent evolutionary events that converge on common phenotypes. The results of this research can lead to a better understanding of how Müllerian mimicry has evolved in mimetic tiger moths, allowing for further study of this system.