An early and mysterious histerid inquiline from Cretaceous Burmese amber (Coleoptera, Histeridae).

We describe a new genus and species of Histeridae from Upper Cretaceous Burmese amber, Amplectister tenax Caterino & Maddison, gen. & sp. n. This species represents the third known Cretaceous histerid, which, like the others, is highly distinct and cannot easily be placed to subfamily. It exhibits prosternal characters in common with Saprininae, but other characters appear inconsistent with this possibility. The abdominal venter is strongly concave, and the hind legs are enlarged and modified for grasping. We hypothesize that this represents the earliest example in Histeridae of modifications for phoresy on social insects.