The fossils were first discovered by an expedition led by Jose Bonaparte during the 1970s to the El Tranquilo Formation.[2] There the team found fossilised eggs and hatchlings, which added insight into the reproductive strategies of Mussaurus and other prosauropod dinosaurs.[2] Although the specimens' young biological age gave them proportions that would be highly atypical for an adult prosauropod, that they were indeed prosauropods was easily ascertained by examination of the limbs and pelvic bones.[2]