Aardonyx

What it was like

Aardonyx was a plant eater about 8 meters (26 feet) long, an early member of the long-necked line that later produced the giant sauropods. It had a long neck, a small head and a bulky body.

Its bones show a body caught partway through a big change. Its hips and legs suggest it usually walked on its hind legs, but its arms show features seen in later four-legged sauropods, so it may have dropped onto all fours at times.

Its world

It lived from about 201 to 193 million years ago, in the Early Jurassic, in what is now South Africa. Its bones come from the Elliot Formation, where it shared the land with the plant eater Massospondylus, the small beaked Heterodontosaurus and Lesothosaurus, and the hunters Dracovenator and Megapnosaurus.

How it was found

Yates and colleagues named Aardonyx in 2010. The type species is Aardonyx celestae. Only one find is known, but it matters: it helps show how sauropod ancestors moved from two legs toward four.