Morphological, palaeontological and molecular aspects of ichneumonoid phylogeny (Hymenoptera, Insecta)

Abstract

Ichneumonoid phylogeny is revised on the basis of morphological, palaeontological and molecular evidence. The only previous formal cladistic study of the phylogeny of the families of the superfamily Ichneumonoidea made many assumptions about what families lower taxa belonged to and was based on a very limited set of characters, nearly all of which were uninformative at family level. We have subdivided both Ichneumonidae and Braconidae into major groups, investigated several new character systems, reinterpreted some characters, scored several character states for extinct taxa by examining impression fossils using environment chamber scanning electron microscopy, and included data for a significant new subfamily of Braconidae from Cretaceous amber of New Jersey. Sixteen different variants of the data set were each subjected to parsimony analysis without weighting and with successive approximations weighting employing both maximum and minimum values of both the retention and rescaled consistency indices. Each analysis resulted in one of seven different strict consensus trees. Consensus trees based on subsets of these trees, selected on the basis of the optimal character compatibility index (OCCI), resulted in an eighth distinct tree. All trees had the Braconidae monophyletic with the Trachypetinae as the basal clade, and also had a clade comprising various arrangements of Apozyginae, the Rhyssalinae group, Aphidiinae and ‘other cyclostomes’, but relationships among the remaining braconid groups varied between trees. Only one of the consensus trees had the Ichneumonidae (including Tanychorella) monophyletic. The Eoichneumonidae + Tanychora are the sister group the Braconidae in two of the consensus trees. Paxylommatinae were basal in the clade comprising the Eoichneumonidae + Tanychora and the Braconidae. The preferred tree, based on the highest OCCI was used for interpreting character state transitions.

Gross morphology of multiporous plate sensilla in the Hymenoptera (Insecta)

“…However, there can be no doubt that paxylommatines are perfectly good ichneumonoids (Sharkey & Wahl 1992; Belshaw et al . 1998; Quicke et al . 1999).…”

A phylogenetic analysis of the Mimagathidini with revisionary notes on the genus Stantonia Ashmead, 1904 (Hymenoptera: Braconidae: Orgilinae)

“…Here we use neither because the consistency index is flawed by being able to give a higher weight to characters that actually carry less phylogenetic signal (as indicated by the retention index, RI), and the rescaled consistency index (being the product of the retention index and consistency index, CI) fails to overcome this. Therefore we use here the retention index (base weight~1, and therefore treated by PAUP* as a real number) (Quicke et al, 1999;Gauthier et al, 2000;Basibuyuk et al, 2002).…”

Estimating the age of the polydnavirus/braconid wasp symbiosis

“…Protorhyssalus goldmani (33,34), from Ϸ93 mya, was considered assignable to either the cyclostome (predominantly ectoparasitoid) lineage of braconid wasps or alternatively to the predominantly endoparasitoid helconoid assemblage. The more recent (Ϸ45 mya) Baltic fossils all are referable to extant subfamilies, some of which possess polydnaviruses.…”