MOLECULAR PHYLOGENY OF THE INSECT ORDER HYMENOPTERA - APOCRITAN RELATIONSHIPS

Phylogenetic relationships among the major groups of hymenopteran inse cts were investigated by using comparative sequence information from t he mitochondrial 16S rRNA gene. The placement of the ectoparasitic Ste phanidae as the sister group to the remaining Apocrita confirmed ectop arasitism as the ground plan biology for the Apocrita. Endoparasitism evolved at least eight times within the Apocrita, and the consequent a ssociation with polydnaviruses and virus-like particles evolved at lea st three times. The Evaniomorpha were consistently placed as basal to the remaining Apocrita but were not resolved as monophyletic. The Gast eruptiidae were resolved as the sister group to the Evaniidae, but the relationship between the Trigonalyoidea and the Evanioidea was unclea r. The Proctotrupomorpha (sensu Rasnitsyn) was resolved by topology-de pendent permutation tail probability (T-PTP) testing as monophyletic, with strong evidence for a sister group relationship between the Platy gastroidea and the Chalcidoidea. Strong evidence was found for the mon ophyly of the Ichneumonomorpha (Ichneumonidae + Braconidae) and the si ster-group relationship between the Aculeata (Vespomorpha) and the Ich neumonomorpha.