Tritylodontids (Tritylodontidae) (meaning: "three knob teeth") were a group of cynodont type therapsids. They were small to medium-sized and very mammal-like herbivores. Still they were not the ancestors of mammals, but were part of another cynodont group. Tley first appeared in Late Triassic and survived to the Late Cretaceous. They were last non-mammal synapsids to go extinct.