New genus and species of phyllocarid (Malacostraca: Phyllocarida: Hoplostraca) from the Early Mississippian of Ohio, USA

Abstract A new genus and species of hoplostracan crustacean from Ohio, USA, Aridelocaris ohioensisn. gen., n. sp., extends the range of Hoplostraca and Sairocarididae into the Early Mississippian (Tournaisian) and echoes the Laurussian biogeographic distribution for most middle Paleozoic malacostracans. Preservation in a concretion yielded more three-dimensional preservation than seen in any other taxon of Hoplostraca and presents detail of the carapace morphology justifying a new genus. The new genus exhibits different carapace and telson morphology from the previously known genera, expanding the known morphological variation within Hoplostraca.