Molecular systematics of the Dichopetala genus group (Orthoptera: Phaneropteridae)

Abstract

The Dichopetala genera group was proposed recently after revision of the genus Dichopetala Brunner von Wattenwyl, 1878. Currently, the group consists of eight genera and 44 species distributed from southern United States to southern Mexico. This generic arrangement was based only on morphological evidence, and was accompanied by discussions on the new erected genera, for which their monophyly was not tested. In this study we assessed the phylogenetic relationships among representative species of the eight genera of the Dichopetala genera group. For this, we generated DNA sequences for one mitochondrial (Cytochrome oxidase I: COI) and two nuclear (28s, Histone III: H3) markers, and included specimens of other phaneropterine genera to test the monophyly of the ingroup. Our results support the monophyly of the Dichopetala genera group and the monophyly of genera Dichopetala, Obolopteryx and Planipollex. In addition, genera Rhabdocerca, Acanthorintes, and Pterodichopetala were recovered as paraphyletic. The mitochondrial markers also suggest that the widely distributed genera Rhabdocerca and Acanthorintes, may actually contain various overlooked species. A more robust phylogenetic and morphological definition of some of the genera involved is provided.