Eothyrididae (asigned to Pelycosauria by Romer and Price, 1940) were a small group of very primitive, insectivorous synapsids. Only two genera are known, Eothyris and Oedaleops, both from the early Permian of North America. Their main distinguishing feature is the large caniform tooth in from of the maxilla, eothyridids share with the Caseidae a number of specialised features associated with the morphology of the snout and external naris and it is likely that they were ancestral to them. The two together form the clade Caseasauria.
Species[]
Oedaleops campi[]
Oedaleops campi (Langston, 1965) was a insectivore eothyridid, its kull fragments from three individuals and some limb elements were found in the Abo Cutter formation in New Mexico. It is dated to the Sakmarian age of the early Permian.