Scelidosaurus

Scelidosaurus (IPA: /ˌskɛlɪdəˈsɔːɹəs/, meaning "limb lizard", from Greek skelos/σκελος meaning 'leg' and saurus/σαυρος meaning 'lizard') was a genus of quadrupedal, lightly plated, herbivorous dinosaur about 4 metres long. It lived during the Early Jurassic Period, during the Sinemurian to Hettangian stages around 194 to 208 million years ago. Its fossils have been found in both England and in Arizona, in the United States. Scelidosaurus has been called the earliest complete dinosaur. This genus and related genera have been found on three continents.

Comparative anatomist Richard Owen described Scelidosaurus in 1859. Only one species, S. harrisonii, is considered valid today, although other species have been proposed over the years. One of the most primitive of the thyreophorans, the exact placement of Scelidosaurus within the suborder has been the subject of debate for nearly 150 years. This is not helped by the meagreness of knowledge of its close relatives.