Earliest stegosaur dinosaur

Re-excavation of the type site of the Sharp's Hill Formation (Bathonian, Middle Jurassic) in Oxfordshire, England, has revealed several horizons with disarticulated remains of a species of stegosaurian dinosaur, here considered to be the earliest stegosaur. It is suggested that stegosaurs radiated out from northern Europe in the Middle and Upper Jurassic to the rest of the world. The general stratigraphy of the type site is described, and it is concluded that the stegosaur remains are possibly of earliest Lower Bathonian age. The sediment in which the remains accumulated is considered to represent a drought-controlled environment.