According to morphological systematics, reptiles include the main orders Rhynchocephalia (tuatara), Squamata (lizards, snakes), Chelonia (tortoises, turtles, and terrapins), and Crocodilia (alligators, crocodiles, caimans, and gavials).
La systématique distingue plusieurs ordres chez les reptiles: les rhynchocéphales (les tuatara), les squamates (lézards, serpents), les chéloniens (tortues) et les crocodiliens (crocodiles, alligators, caïmans).
