Borchgrevinkium

Borchgrevinkium is an extinct, monotypic genus of chelicerate arthropod known from a single fossil of its only species, Borchgrevinkium taimyrensis, collected in 1956 from Early Devonian deposits near the Imangda River on the Taimyr Peninsula in Siberia, Russia, and described in 1959 by Nestor Novojilov. The animal had a long, nearly U-shaped head, elongated first and second body segments, paired ridges on its surface, a triangular trunk, and a short wedge-shaped tail spine. Its classification has shifted repeatedly since its description, having been placed at different times among the eurypterids, the xiphosurans, and most recently a tentative clade called Prosomapoda, and its true affinities remain unresolved for lack of further fossil material. The genus is named for the Anglo-Norwegian Antarctic explorer Carsten Borchgrevink.