Stegosaurs History and Discoveries
The first stegosaurs were discovered in England in the 1870s, but they were so fragmented that the fact that it was a discovery of a new clade of dinosaurs didn't spark much attention. The bones were however studied by some of the great paleontologists of the time such as Sir Richard Owen and H.G. Seeley, and they were originally named Dacentrurus (da-very; kentron-spiny; oura-tail) and Lexovisaurus (after the people of Lexovii Europe). At the same time these dinosaurs were being found in North America at such sites as Como Bluff and Wyoming, where virtually complete skeletons were being found amongst the remains. Since then, the focus of stegosaur discoveries has been in North America but they are found in Africa and Asia as well.
It is believed that the stegosaur first appeared in either Europe or Asia during the Early Jurassic and they reached their prime during the late Jurassic and they finally disappeared during the mid-late Cretaceous making them one of the first dinosaurs to go extinct.