Afristenus orapensis: A new genus and species of Steninae (Coleoptera: Staphylinidae) with “harpoon-like” mouthparts from the Upper Cretaceous lacustrine deposits at Orapa Diamond Mine, Botswana

Abstract

A new genus and species of rove beetle, Afristenus orapensis gen. et sp. nov., is described and figured based on one well-preserved compression fossil from the African, Upper Cretaceous fossil insect deposit, Orapa Diamond Mine in north-east Botswana. Afristenus is definitively placed in the extant subfamily Steninae based on its harpoon-like labial feeding apparatus. Afristenus differs from all other Steninae by head and neck behind the eyes being broader than eyes that cover two-thirds of the side of the head and transverse prothorax, which is distinctly broader than the head. The new specimen from Orapa Diamond Mine possibly has unique antennae with a compact 5-segmented-club, and a stem composed of elongated antennal segments. This is the first stenine compression fossil with a preserved labial feeding mechanism. It confirms the widespread distribution of stenines with this feeding apparatus in the mid-Cretaceous; supporting the hypothesis that this feeding mechanism was part of the ground plan of the Steninae, and the Lower Cretaceous, but probably not Jurassic origin for the group. It also demonstrates morphological conservatism dating back to the Cretaceous.