Parareptile

Evolutionary history

The oldest known "parareptiles" are the bolosaur Erpetonyx and the acleistorhinid Carbonodraco from the Late Carboniferous (Moscovian-Gzhelian) of North America, which represents the only known Carboniferous "parareptiles", indicating that the initial diversification of the group took place in the Late Carboniferous. Numerous "parareptile" lineages appeared during the early Permian and the group reached a cosmopolitan distribution. "Parareptile" diversity declined towards the end of the Permian and procolophonoids, which first appeared during the Late Permian, were the only group of "parareptiles" to survive the Permian–Triassic extinction event. Procolophonid diversity sharply declined beginning in the Middle Triassic, with the group becoming extinct by the end of the Triassic.