Euoplocephalus ( ) is a genus of very large, herbivorous ankylosaurid dinosaurs, living during the Late Cretaceous of Canada. It has only one named species, Euoplocephalus tutus. The first fossil of Euoplocephalus was found in 1897 in Alberta. In 1902, it was named Stereocephalus, but that name had already been given to an insect, so it was changed in 1910. Later, many more ankylosaurid remains were found from the Campanian of North America and often made separate genera. In 1971, Walter Coombs concluded that they all belonged to Euoplocephalus which then would be one of the best-known dinosaurs. Recently however, experts have come to the opposite conclusion, limiting the authentic finds of Euoplocephalus to about a dozen specimens. These include a number of almost complete skeletons, so much is nevertheless known about the build of the animal. Euoplocephalus reached in length and in body mass. Its body was low-slung and very flat and wide, standing on four sturdy legs. Its head had a short drooping snout with a horny beak to bite off plants that were digested in the large gut. Like other ankylosaurids, Euoplocephalus was largely covered by bony armor plates, among them rows of large high-ridged oval scutes. The neck was protected by two bone rings. It could also actively defend itself against predators like Gorgosaurus using a heavy club at the end of its tail. Description Size Among the ankylosaurids, Euoplocephalus was exceeded in size only by Ankylosaurus, and perhaps Tarchia and Cedarpelta. Euoplocephalus was about long and weighed about . Like other ankylosaurids, it had a very broad and flat low-slung torso, about four feet high, positioned on four short legs. Distinguishing traits The skull of Euoplocephalus can be distinguished from most other ankylosaurids by several anatomical details, including: the pattern of bony sculpturing in the region in front of the eyes; the form of the palpebral bones (small bones over the eyes), which may have served as bony eyelids; the shallowness of the nasal vestibule at the entrance of the nasal cavity; the medial curve of the tooth rows in the upper jaw; and the teeth, which are relatively small, lacking true cingula, and having variable fluting of the denticles. However, these traits are shared with a number of closely related forms, some of which in the past have been included in the genus. Combining such forms, Walter Coombs and Teresa Maryańska in 1990 stated