Trityldon(Greek for 3 cusped tooth) was a species of tritylodont, one of the most advanced group of cynodont therapsids. They lived in the Early Jurassic and possibly Late Triassic periods along with dinosaurs. They also did share a lot of characteristics of mammals, and were once considered mammals because of overall skeleton construction. That was changed due to them retaining the vestigial reptilian jawbones and a different skull structure. So they're now regarded as synapsids (often called… (More on Tritylodon)