A review of the mature larvae of Diplazontinae, with notes on larvae of Acaenitinae and Orthocentrinae and proposal of two new subfamilies (Insecta: Hymenoptera, Ichneumonidae)

Abstract

Study of larval diplazontine ichneumonids reveals that previous authors misinterpreted basic morphology and that larvae have little value for defining diplazontine genera or elucidating their relationships. Better understanding of diplazontine larvae, combined with new material of Orthocentrus, has led to recognition that Pimplinae, Acaenitinae, Diplazontinae, and Orthocentrinae form a monophyletic group, informally named Pimpliformes. Oxytorus and Tatogaster are not part of this group; Oxytorinae is restricted to Oxytorus and Tatogaster is placed in a new subfamily (Tatogastrinae). In order to establish monophyletic taxa within Pimpliformes, Cylloceria and Alomacrus are placed in a new subfamily (Cylloceriinae) and the remaining former oxytorines are merged with orthocentrines in an expanded Orthocentrinae.