It is known from the holotypeYPM 796, a partial skeleton. It was collected in the Mazon Creek site, from the Francis Creek Shale Member of the Carbondale Formation. It was first named by R. L. Moodie in 1912 as an amphibamid amphibian and the type species is Cephalerpeton ventriarmatum.[2] It was first assigned to Protorothyrididae by Robert L. Carroll and Donald Baird in 1972 and this placement has been widely accepted.[3][4]
^R. L. Moodie (1912). "The Pennsylvanic Amphibia of the Mazon Creek, Illinois, Shales". Kansas University Science Bulletin. 6 (2): 232–259.
^Robert L. Carroll; Donald Baird (1972). "Carboniferous Stem-Reptiles of the Family Romeriidae". Bulletin of the Museum of Comparative Zoology. 143 (5): 321–363.