EUNOTOSAURUS

genus of extinct reptiles found as fossils in Permian deposits of South Africa (the Permian Period lasted from 286 to 245 million years ago). It has been suggested that Eunotosaurus may be the ancestral form from which the turtles evolved. The structure of Eunotosaurus is unusual; the number of vertebrae in the backbone is small, a condition seen in the turtles, and these reptiles had eight pairs of very broad ribs almost touching each other, a condition that may foreshadow the development of the turtle carapace, or shell.