Neopteroplax

Neopteroplax is an extinct genus of eogyrinid embolomere closely related to European genera such as Eogyrinus and Pteroplax. Members of this genus were among the largest embolomeres (and Carboniferous tetrapods in general) in North America. Neopteroplax is primarily known from a large (~40 cm) skull found in Ohio, although fragmentary embolomere fossils from Texas and New Mexico have also been tentatively referred to the genus. Despite its similarities to specific European embolomeres, it can be distinguished from them due to a small number of skull and jaw features, most notably a lower surangular at the upper rear portion of the lower jaw.