Carboniferous amphibians

Crassigyrinus (from , 'thick' and , 'tadpole') is an extinct genus of carnivorous stem tetrapod from the Early Carboniferous Clackmannan Group of Scotland and possibly Greer, West Virginia.

Acherontiscus is an extinct genus of stegocephalians that lived in the Early Carboniferous (Mississippian era) of Scotland. The type and only species is Acherontiscus caledoniae, named by paleontologist Robert Carroll in 1969. Members of this genus have an unusual combination of features which makes their placement within amphibian-grade tetrapods uncertain. They possess multi-bone vertebrae similar to those of embolomeres, but also a skull similar to lepospondyls. The only known specimen of Acherontiscus possessed an elongated body similar to that of a snake or eel. No limbs were preserved, a

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 suran