Massospondylus (/ˌmæsoʊˈspɒndɪləs/ mas-oh-SPON-di-ləs; from Greek, μάσσων (massōn, "longer") and σπόνδυλος (spondylos, "vertebra")) is a genus of sauropodomorph dinosaur from the Early Jurassic Period (Hettangian to Pliensbachian ages, ca. 200–183 million years ago). It was described by Sir Richard Owen in 1854 from remains discovered in South Africa, and is thus one of the first dinosaurs to have been named. Fossils have since been found at other locations in South Africa, Lesotho, and Zimbabwe. Material from Arizona's Kayenta Formation, India, and Argentina has been assigned to this genus at various times, but the Arizonan and Argentinian material are now assigned to other genera.