Mussaurus (meaning mouse lizard) is a genus of herbivorous prosauropod dinosaurs from Late Triassic Argentina. It receives its name from the small size of the skeletons of juvenile and infant individuals, which were once the only known specimens of the genus. However, since Mussaurus is now known from adult specimens, the name is something of a misnomer; adults possibly reached 3 m (10 ft) in length, and weighed 70 kilograms (150 lb).

Infant and juvenile fossils of Mussaurus were first discovered by an expedition led by Jose Bonaparte during the 1970s to the El Tranquilo Formation. There the team found fossilized eggs and hatchlings, which added insight into the reproductive strategies of Mussaurus and other sauropodomorph dinosaurs. The first adult specimens of Mussaurus were described in 2013. Some of these specimens had first been described in 1980 and were originally attributed to the genus Plateosaurus.

Mussaurus in The Land Before Time



The Tinysauruses from The Land Before Time XI: Invasion of the Tinysauruses, also known as Tiny Longnecks, are Mussaurus.[Citation Needed] They, alongside Plateosaurus and Lufengosaurus, are the only prosauropods to appear in the franchise. Unlike their reality counterparts, the adults are the same size as the younger Mussaurus. They come in many different colors. The most notable "tinysauruses" to appear in the film are Big Daddy, Lizzie, Skitter, and the twins; Rocky and Dusty.