Twangsteini—a New Tribe of the Subfamily Pimplinae (Hymenoptera, Ichneumonidae) from Baltic Amber.

A new tribe Twangsteini trib. nov. (Hymenoptera, Ichneumonidae, Pimplinae) including a new genus Twangste gen. nov. with a new species T. belokobylskiji sp. nov. is described from Late Eocene Baltic amber. The tribe Twangsteini is interpreted as an extinct, basal and at the same time strongly advanced phylogenetic lineage of Pimplinae. This inference is based on a number of characters in which it resembles the Mesozoic subfamily Labenopimplinae and a number of apomorphies and plesiomorphies. Morphological similarity with the extant "Polysphincta" group of genera is the basis for the assumption that Twangste developed as a parasitoid on adult spiders (Arachnida, Araneida) or in their egg cocoons, supposedly the primary biology for the Polysphincta genus group. [ABSTRACT FROM AUTHOR]