Dicynodonts 2

More sketches illustrating dicynodont diversity. Again, not to scale except for the last picture showing how Robertia (from the previous dicynodont sketch) measures up to Ischigualastia.

Endothiodon was one of the first large dicynodonts, reaching a length of about 2 m/7', living in the late Permian, after the extinction of the Dinocephalians. An entire zone of fossils here in South Africa is named after it. Unlike other dicynodonts it apparently did not have tusks in its upper jaw. Endothiodon might have lived in South America as well ... the continents were joined in those days, so it would not have been unusual.

Aulacephalodon was a medium- to large-sized dicynodont, with a rather strange, low skull with bumps over the nose and eyes. It lived in the late Permian period, about 255-260 million years ago, and its fossils were found in South Africa and Zambia.

Emydops was a small (30-40 cm) dicynodont from South Africa. In shape it can be considered a very typical member of the group. It lived in the middle Permian.

Ischigualastia was a giant dicynodont from South America. It is named for the Ischigualasto Geological Formation of Argentina which preserves ancient synapsids and reptiles as well as some of the earliest dinosaurs. Ischigualastia was one of the largest dicynodont species, perhaps reaching 4 m in length. Here it is illustrated with little Robertia perched on its head to vividly show the size range of the dicynodonts. Note that this could never have happened in real life; Robertia lived in the middle Permian while Ischigualastia lived in the Late Triassic, about 30 million years later. Ischigualastia and some other Triassic dicynodonts have a modification of the tusks - there are downward angled extensions of the upper jaw, not actual teeth. These extensions might have been covered with a horny sheeth just like the rest of the toothless beak.