New species‐group of brachypterous Idris Förster, 1856 s.l. (Hymenoptera: Platygastridae s.l.) from the Oriental region

Abstract

AbstractMembers of the cosmopolitan wasp tribe Baeini (Platygastridae s.l.) are obligate endoparasitoids of spider eggs. The group is estimated to have well over 2000 species globally, approximately 80% of which are undescribed. Most species belong to the genus Idris Förster s.l., a megadiverse group which is probably paraphyletic without the inclusion of a number of smaller genera. The group has resisted phylogenetic analysis using morphology largely due to convergence associated with reductional character states or, in the case of molecular analysis, insufficient taxon sampling and markers. To make any headway in understanding the diversity and relationships within the tribe, and particularly for the genus Idris, a pragmatic approach is to describe species groups that can be later incorporated into a broader sampling of taxa for molecular analysis. In taking this approach, we describe two new species from the Oriental region (India) with brachypterous females, Idris benaka sp. nov. and Idris samueli sp. nov., which are assigned to a new species group, the ‘benaka‐group’. These two species are morphologically similar to a number of undescribed Idris from Australia and southern Africa which, if related, point to a possible circum‐Indian Ocean distribution for this species group. In addition, we also discuss the make‐up and relationships of Idris, and the nature of wing reduction in the Baeini.