Phylogeny of the subfamily Braconinae (Hymenoptera: Braconidae)

Abstract

The phylogeny of the parasitic wasp subfamily Braconinae was estimated using both nuclear [28S rDNA] and mitochondrial [C01 and NADH1] genes along with morphological characters. The phylogenetic tree obtained from the nuclear 28S rDNA failed to resolve this subfamily as monophyletic and divided into two monophyletic tribes, the Aphrastobraconini and Braconini, with the Coeloidini in the middle as was established by previous studies. The Compsobraconides, Virgulibracon, Myosoma, Shelfordia and Atanycolus genus-groups were recovered as monophyletic. However, some tribes and genus groups, based on traditional classification, were not recovered as expected. Therefore, a character re-weighting criterion, devised by Goloboff, was used to downweight any noise in the data, though this procedure also revealed almost similar results. Both of the mitochondrial genes, C01 and NADH1, were also unable to recover a monophyletic Braconinae on their own. Although two different methods of phylogeny reconstruction, maximum parsimony and Bayesian analysis were used, similar results were obtained. However, both of the mitochondrial genes divided the genus Bracon into meaningful groups based on the geographic origin of the species sequenced. The combined analysis of nuclear [28S rDNA] and mitochondrial [NADH1] genes revealed Braconinae to be monophyletic and comprised two monophyletic tribes, Aphrastobraconini and Braconini. This combined analysis has recovered the genus Digonogastra and the Atanycolus-group of genera as monophyletic. The rooting of the phylogentic tree was different from the one obtained from the analysis of nuclear gene [28Sr DNA] alone and this is discussed in chapter 7.