Batriscydmaenus Parker and Owens, New Genus, and Convergent Evolution of a “Reductive” Ecomorph in Socially Symbiotic Pselaphinae (Coleoptera: Staphylinidae)

We describe a new genus and new species of pselaphine rove beetle, Batriscydmaenus tishechkini Parker and Owens, from lowland Panamanian rainforest. The new taxon marks a radical departure from the basic pselaphine anatomical groundplan, with a globose body shape and a dramatic reduction of foveae, sulci and striae—features that are considered plesiomorphic in Pselaphinae. This overt simplification of the integument is typical of myrmecophile...