Cotylorhynchus was a very large Synapsid that lived in the southern part of what is now North America during the Early Permian period. It was one of the largest terrestrial vertebrates of the Early Permian. Like rhinoceros, it is a solitary but peaceful herbivore in general. The mothers raise their babies until they are old enough to fend for themselves.
Cotylorhynchus was briefly shown in a Chinese prehistoric documentary :"Back to the Permian 4D" (http://txyy.cansm.org/ypzy/490.jhtml )