Osteichthyes - Synapsida - Ophiacodontidae
Synonyms: Clepsydropidae Cope 1878, Clepsydropsidae Cope 1878, Poliosauridae Case 1907
Parent taxon: Eupelycosauria according to R. R. Reisz 1986
See also Carroll 1988, Case 1907, Case 1910, Cope 1878, Gardiner 1982, Hay 1902, Hay 1930, Kemp 1982, Kissel and Lehman 2002, Kuhn 1946, Kuhn 1966, Lewis and Vaughn 1965, Nopcsa 1923, Perrier 1928 and Romer and Price 1940
Sister taxa: Edaphosauridae, Haptodontiformes, Sphenacomorpha, Varanopidae
Subtaxa: Archaeothyris Arribasaurus Baldwinonus Clepsydropinae Clepsydrops Diopeus Elcabrosaurus Ophiacodon Scoliomus Stereophallodon Stereorhachis Varanosaurus
Type: Ophiacodon
Ecology:
Distribution:
• Permian of the United Kingdom (1 collection), United States (64: Colorado, Kansas, New Mexico, Ohio, Oklahoma, Texas, Utah)
• Carboniferous to Permian of United States (3: New Mexico, Utah)
• Carboniferous of Canada (1: Nova Scotia), the Czech Republic (1), France (1), United States (6: Illinois, Kansas, New Mexico, Ohio, Oklahoma, Pennsylvania)
Total: 77 collections including 105 occurrences