Tyrannosaurus lived throughout what is now western North America. Fossils are found in a variety of rock formations dating from 67 to 65.5 million years ago. Tyrannosaurus was a bipedal carnivore with a massive skull balanced by a long, heavy tail. Relative to the large and powerful hindlimbs, Tyrannosaurus forelimbs were small, though unusually powerful for their size, and bore two clawed digits. It was the largest known tyrannosaurid and one of the largest known land predators, measuring up to 12.8 m (42 ft) in length, up to 4 metres (13 ft) tall at the hips, and up to 6.8 metric tons (7.5 short tons) in weight. Modern representations in museums, art, and film show Tyrannosaurus rex with its body approximately parallel to the ground and tail extended behind the body to balance the head. Since it was first described in 1905, Tyrannosaurus rex has become the most widely recognized dinosaur species in popular culture. It is the only dinosaur that is commonly known to the general public by its full scientific name - Tyrannosaurus rex. It has been frequently represented in film and on television, in literature, and on the internet.