(class Reptilia, subclass Archosauria)
An order of ‘tooth-in-socket’ (i.e. thecodont) reptiles, and the most primitive of the archosaurs, that ranged from the Late Permian to the Late Triassic. Thecodontosaurus browni was one of the first of the group. It grew to 2–3 m in length and had a small head and neck. Essentially it was a quadruped, but it could walk on its hind legs. The Thecodontia were ancestral to the dinosaurs, pterosaurs, and crocodiles. Apart from a limited number of primitive features in the skull, Euparkeria, a thecodont from the Early Triassic, is a likely ancestor for most archosaurian stocks. It was a small reptile, only 60–100 cm in length.
Subjects: Zoology and Animal Sciences — Earth Sciences and Geography.