Phylogenetic relationships among genera of danaine butterflies (Lepidoptera: Nymphalidae) as implied by morphology and DNA sequences

Cladistic relationships among genera and subtribes of Danaini (the milkweed butterflies) were inferred by analysis of data combined from five sources: morphology of adults and immature stages, and DNA sequences from three gene regions. The results corroborate and greatly increase support for prior hypotheses based on morphology alone. A new index summarizing incongruence among data partitions, the Partition Congruence Proportion (PCP), is introduced. The significance of the inferred pattern of phylogenetic relationships for comparative chemical ecology of milkweed butterflies is briefly discussed.