Ophiacodontidae

Ophiacodontidae Temporal range: Late Carboniferous to Early Permian 308–280 Ma PreꞒ Ꞓ O S D C P T J K Pg N
Mounted skeleton of Ophiacodon retroversus in the American Museum of Natural History
Scientific classification
Domain:	Eukaryota
Kingdom:	Animalia
Phylum:	Chordata
Clade:	Synapsida
Clade:	Metopophora
Family:	†Ophiacodontidae Nopcsa, 1923
Subgroups[1]
†Archaeothyris †Baldwinonus †Clepsydrops †Echinerpeton †Ophiacodon †Protoclepsydrops? †Stereophallodon †Stereorhachis †Varanosaurus

Ophiacodontidae is an extinct family of early synapsids from the Carboniferous and Permian. Archaeothyris, and Clepsydrops were among the earliest ophiacodontids, appearing in the Late Carboniferous. Ophiacodontids are among the most basal synapsids, an offshoot of the lineage which includes therapsids and their descendants, the mammals. The group became extinct by the Kungurian or the Roadian,^[2] replaced by anomodonts, theriodonts, and the diapsid reptiles.