floodplain deposits of the Lower Jurassic Elliot Formation (upper Karoo Supergroup). In this area there have been so many findings it has been named the Tritylodon Acme Zone. The fossil findings have all been in the Free State of South Africa. The genus Tritylodon of the Tritylodonts is restricted to the South African forms: Tritylodon longaevus and Tritylodon maximus. It is suggested that T. maximus is either a large T. longeavus or a closely related species. If it is a closely related species it could possibly be ecological succession since the larger T. maximus fossils have been dated in the Sinemurian–Pliensbachian mainly less than 190 million years ago and the T. longaevus in the Hettangian–Sinemurian mainly more than 190 million years ago. With the fossil findings of each species overlapping in Sinemurian stage, the fossils show two differences, T. maximus being larger and having nine upper postcanines (neither species had canine teeth) instead of the seven teeth like T. longeavus. All other structures of the two Tritylodon'' species were the same. Below is a cladogram from Ruta, Botha-Brink, Mitchell and Benton (2013) showing one hypothesis of cynodont relationships: References External links https://archive.today/20130204222846/http://tritylodontidae.totallyexplained.com/ Prehistoric cynodont genera Jurassic synapsids of Africa Fossil taxa described in 1884 Taxa named by Richard Owen Tritylodontids