Lessemsaurus sauropoides

Lessemsaurus was one of the earliest known true sauropods; hailing from the Late Triassic of Argentina. It was small for a sauropod, growing to an adult length of around 9 meters (30 feet). It would have closely resembled some of its "prosauropod" kin, and for many year was considered one itself, but Lessemsaurus shows more advanced features such as a weight-bearing, columnar-type limb configuration that would be taken to further extremes in later sauropods. The name refers to science/biology author Don Lessem; who wrote many popular books on dinosaurs.