Prosolierius, a new mid-Cretaceous genus of Solieriinae (Coleoptera: Staphylinidae) with three new species from Burmese amber

Investigation of the well-preserved fauna in Cretaceous amber deposits from Myanmar (Burma) continues to illuminate the evolution of the beetle family Staphylinidae, particularly within the Staphylinine group of subfamilies. We document the unexpected discovery of the hypothesized sister group of the monotypic austral South American genus Solierius, previously the sole known member of Solieriinae, in both Burmese deposits and the Cretaceous of Lebanon. The higher species richness of Solieriinae in the Cretaceous suggests a relict status for Solierius. This discovery further documents the active Cretaceous diversification and long-standing wide distribution of the Staphylinine group of Staphylinidae. It also provides an additional cautionary example of a now seemingly Gondwanan relict group whose roots are not necessarily Gondwanan.

► We describe a new genus with three new species, the first fossils of Solieriinae.
► The formerly monotypic southern South American Solieriinae is quadrupled in size.
► Solieriinae is newly recorded from the Cretaceous of Myanmar and Lebanon.
► We extend the known history of Solieriinae back to early Cretaceous (Neocomian).
► Prosolierius reinforces origin of the Staphylinine group before Late Jurassic.