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a superorder of extinct reptiles of the subclass Archosauria that lived in the Triassic. The superorder consisted of two suborders, Pseudosuchia and Phytosauria. All representatives had teeth set in alveoli; hence the name “Thecodontia” (“with tooth sockets”). Thecodonts were predators. Some walked on two legs. The superorder is important from the point of view of evolution because it was the origin of all the other groups of Archosauria, including crocodiles, dinosaurs, and pterosaurs (flying reptiles), as well as birds in the late Triassic.