Paleothyris was a small, agile, anapsid romeriidan reptile which lived in the Middle Pennsylvanian epoch in Nova Scotia (approximately 312 to 304 million years ago). Paleothyris had sharp teeth and large eyes, meaning that it was likely a nocturnal hunter. It was about a foot long. It probably fed on insects and other smaller animals found on the floor of its forest home. Paleothyris was an early sauropsid, yet it still had some features that were more primitive, more labyrinthodont-like than reptile-like, especially its skull, which lacked fenestrae, holes found in the skulls of most modern reptiles and mammals.^[1]

Quick Facts Scientific classification, Binomial name ...

Paleothyris Temporal range: Middle Pennsylvanian, 312–304 Ma PreꞒ Ꞓ O S D C P T J K Pg N
Paleothyris acadiana fossil
Scientific classification
Domain:	Eukaryota
Kingdom:	Animalia
Phylum:	Chordata
Class:	Reptilia
Genus:	†Paleothyris Carroll, 1969
Species:	†P. acadiana
Binomial name
†Paleothyris acadiana Carroll, 1969

Close

• Westlothiana, from 335 million years ago, either an early amniote or a sister group to the amniotes
• Casineria, from 340 million years ago, a basal amniote.
• Hylonomus, from 312 million years ago, another early anapsid reptile
• Petrolacosaurus, from 302 million years ago, the first diapsid reptile
• Archaeothyris, from 306 million years ago, an early synapsid (proto-mammal)
• Carboniferous tetrapods