A phylogenetic examination of the Ctenuchina and Euchromiina (Lepidoptera: Erebidae: Arctiinae: Arctiini)

Members of Ctenuchina and Euchromiina 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 ctenuchines and euchromiines are obscured, impeding our understanding of how these subtribes are related, how species within the tribes are related and how mimetic traits were acquired in these lineages. Previous classifications have relied on visible adult morphological characteristics, particularly wing venation, to classify genera with the subtribes. These treatments often resulted in non-monophyletic groupings. While molecular phylogenies have yet to be sufficient in taxon sampling to give us a better understanding of the relationships. Here we constructed a phylogeny for the Ctenuchina and Euchromiina using molecular data from eight loci ~ 100 species that span the diversity of the two subtribes. The loci sampled included: cytochrome oxidase I (COI), the DI region of the 28S ribosomal DNA (DI), the DII region of the 28S ribosomal DNA (DII), Elongation Factor 1-alpha (EF1-α), glyceraldehyde-3-phosphate dehydrogenase (GAPDH), isocitrate dehydrogenase (IDH), ribosomal protein S5 (RPS5), and wingless (WGL). The results indicate that Ctenuchina and Euchromiina are monophyletic with the exception of the ctenuchine genus Abrochia which were recovered within the Phaegopterina.