(pronounced ˌstɛgəˈsɔrəs) is a genus of stegosaurid thyreophoran dinosaur from the Late Jurassic period (late Kimmeridgian to Early Tithonian) in what is now western North America. In 2006, a specimen of Stegosaurus was announced from Portugal, showing that they were present in Europe as well.Due to its distinctive tail spikes and plates, Stegosaurus is one of the most recognizable dinosaurs, along with Tyrannosaurus, Triceratops, Parasaurolophus, and Apatosaurus. The name Stegosaurus means "roof-lizard"