Testing generic concepts: Phylogenetic analyses of the pelidnotine leaf chafers (Scarabaeidae: Rutelinae: Rutelini)

Phylogenetic analyses were conducted to test the generic concepts of the leaf chafer group Pelidnotina sensu Soula (Scarabaeidae: Rutelinae: Rutelini) which includes 18 genera and about 250 species that are distributed in the New World. Lack of a phylogenetic framework remains an impediment for circumscription of the pelidnotine leaf chafers and for understanding evolution of metallic coloration, enlarged hind femora, circular polarization of light, and herbivory. This research provides a foundation for understanding the biodiversity, evolution, taxonomy, and ecology of these beetles.

Adult morphological characters formed the basis of the study. The analysis included 60 characters, 62 ingroup exempar species, and 20 outgroup species. Previous phylogenetic research provided evidence that the subtribe was polyphyletic, hence we included representative genera from the former subtribes Anticheirina, Rutelina, Lasiocalina (all Rutelini). Outgroups included representative genera from the Anomalini (Rutelinae), Cyclocephalini (Dynastinae), and Oryctini (Dynastinae). We used an exemplar approach, placing a priority on type species for genera and subgenera. For species of Pelidnota sensu lato, we used a wide array of species in order to address the breadth and depth of morphological variation and to test monophyly of genera and species groups.

Results of the analyses do not support the monophyly of the subtribe Pelidnotina sensu Soula. Results of the phylogenetic analyses and character support for lineages are used to inform groupings of species into monophyletic genera.