The oldest fossil axiid (Decapoda: Pleocyemata: Axiidea), from the Late Devonian (Famennian) Chagrin Shale Member of the Ohio Shale, USA

Abstract

Abstract Discovery of a single specimen of a nearly complete cephalothorax and pleon of a new arthropod from the Late Devonian (Famennian) Chagrin Shale Member of the Ohio Shale Formation in Lake County, northeastern Ohio, USA documents the oldest known representative of the Axiidea. The specimen documents a new genus and species, Devonoaxius garlandi, and extends the range of the infraorder from the Jurassic into the Late Devonian. This range extension was predicted by a recent phylogenetic analysis. The addition of this axiid brings to four the number of arthropod genera in the Chagrin Shale Member, two of which represent the oldest members of their lineage.