New World spittlebugs (Hemiptera: Cercopidae: Ischnorhininae): Dated molecular phylogeny, classification, and evolution of aposematic coloration

The spittlebug family Cercopidae (Hemiptera: Auchenorrhyncha: Cicadomorpha: Cercopoidea) is distributed worldwide, with highest species diversity in the tropics. Several included species are economically important pests of major agricultural crops and cultivated pasture grasses. Taxonomically, Cercopidae is divided into two subfamilies: the paraphyletic Old World Cercopinae and the monophyletic New World Ischnorhininae. Results are here presented from an investigation of phylogenetic relationships within Ischnorhininae based on DNA sequences from seven loci (18S rDNA, 28S rDNA, Histone 2A, Histone 3, Wingless, Cytochrome Oxidase I, and Cytochrome Oxidase II) generated from exemplars of 119 spittlebug species. The resulting topology is used to test alternative higher-level classification hypotheses of Ischnorhininae and, with fossil-calibration, dates were estimated for major events in the evolutionary history of Cercopidae, including a much earlier divergence date (around 68-50 Mya) than previously reported in the literature. In addition, for the first time in Cercopidae, ancestral states of some predation avoidances strategies were reconstructed, with results suggesting an origin of aposematic coloration in the Cercopidae ancestor, with subsequent independent losses of aposematic coloration in multiple lineages.