Phylogenetic species delimitation for the widespread spider wasp Ageniella accepta (Hymenoptera: Pompilidae), with new synonyms

Ageniella is the second-most diverse spider wasp genus in Ageniellini (Pepsinae). The Ageniella (Ageniella) accepta species-group is found from Canada to Panama and is composed of three Nearctic species: A. accepta (Cresson), A. blaisdelli (Fox), and A. conflicta Banks. Within this group, species-level identification is difficult, because diagnostic characters are questionable, and subjective for both males and females. Furthermore, sexes of each species are not reliably associated. Herein, we investigate sex associations and the validity of described species within the A. accepta species-group based on three molecular markers (cytochrome oxidase I, wingless, long-wavelength rhodopsin) by using maximum likelihood and Bayesian phylogenetic analyses, and species-delimitation approaches. Additionally, we mapped 12 morphological traits onto the molecular phylogeny to discuss evolution of diagnostic characters. We concluded that the three species of the A. accepta species-group are actually a single, wide-ranging species with strong geographical signal. Moreover, our results suggest introgression at the mitochondrial level.