Molecular phylogeny and systematics of spider wasps (Hymenoptera: Pompilidae): redefining subfamily boundaries and the origin of the family

Abstract

Spider wasps (Hymenoptera: Pompilidae) constitute a monophyletic family supported by numerous morphological and behavioral traits. The subfamilial and tribal classifications, however, have a history of conflicting and confusing designations and nomenclature. Here, we reconstruct a molecular phylogeny of Pompilidae from Bayesian and maximum-likelihood analyses of four nuclear molecular markers (elongation factor– 1 α F2 copy, long–wavelength rhodopsin, RNA polymerase II, and 28S ribosomal RNA). A Bayesian divergence-time estimation was performed using four calibration points. An ancestral-area reconstruction was performed with a Bayesian binary Markov chain Monte Carlo method. New relationships are recovered, and new subfamilial delimitations are proposed and discussed based on the phylogeny. The origin of Pompilidae was ca. 43.3 Ma, probably in the Nearctic region. Most of the extant subfamilies originated during the late Eocene through Oligocene, and their current distributions are the product of various dispersal events that occurred over the course of ~40 Ma. This is the first phylogenetic reconstruction of Pompilidae from molecular characters, with broad geographic and taxonomic sampling. The following subfamilies and relationships are recognized: Ctenocerinae + (Ceropalinae + Notocyphinae) + Pompilinae + Pepsinae. We revalidate Notocyphinae, which contains only Notocyphus, and define a new tribe in Pompilinae: Sericopompilini. Priochilini is reinstated. Sericopompilini contains Sericopompilus as the sole representative; Priochilini contains Priochilus and Balboana. Epipompilus and Chirodamus are now classified as Pepsinae.