Phylogenetic Relationships of the Prodontria (Coleoptera; Scarabaeidae; Subfamily Melolonthinae), Derived from Sequence Variation in the Mitochondrial Cytochrome Oxidase II Gene

The beetle genus Prodontria is of importance to New Zealand conservation programs. All Prodontria species are brachypterous (having reduced wings), and the genus presents some interesting evolutionary and biogeographic questions that are testable using phylogenetic reconstruction. A phylogeny was produced for 14 flightless Prodontria species, 2 macropterous (fully winged) Odontria species, and single representatives of 2 outgroup genera using sequence data from the mitochondrial COII gene. The data support probable conspecificity of the morphologically similar P. modesta and P. bicolorata but do not support their hypothesized sister-species relationship with the geographically proximate P. lewisi. The alpine P. capito is found to be a paraphyletic group, with the most eastern population diverging after the western populations made their appearance. Many interesting biogeographic disjunctions are here proposed to be anomalous and the result of morphological convergence. The data do not support the idea of a common flightless ancester for Prodontria, but suggest that brachyptery has evolved numerous times. In some instances, this appears to have led to contemporaneous speciation resulting in little resolution of phylogenetic relationships in some parts of the tree. These data allow for a new interpretation of the origin and diversification of the southern New Zealand flightless melolonthine fauna. Multiple speciation events involving wing reduction are suggested to involve at least one widespread flighted ancestor that has given rise to brachypterous forms.