Was species diversification in Tenthredinoidea (Hymenoptera: Symphyta) related to the origin and diversification of angiosperms?

Abstract

AbstractThe paraphyletic grouping “Symphyta” (8353 described species) represents the basal lineages of the insect order Hymenoptera. The most species-rich superfamily in Symphyta is Tenthredinoidea (7390 species), with six extant families. Most of tenthredinoids species are phytophagous at the larval stage, and the species using angiosperms as a host are more numerous (6265 species) than those using gymnosperms (140 species) or pteridophytes (985 species). In this study, we investigated whether diversification of Tenthredinoidea could be attributed to their use of angiosperms as hosts by examining host plant usage by lineage. We performed molecular phylogenetic and divergence time estimation analyses using molecular data (~2 kilobase sequence in five DNA regions) and conducted a diversification analysis. Our results suggest that Tenthredinoidea (excluding Blasticotomidae) had used angiosperms since its origin; the phylogeny of Tenthredinoidea showed a significant shift in diversification at two nodes, and those nodes overlap with the periods of origin and diversification of angiosperms.