Tyrannosaurus Rex; Tyrant Lizard King; Carnivore (Apex predator); 3.66-4.36 meters (12-14 feet at the hips); 12.3-13.4 meters (40.4-44.0 feet); 9.8 tons/19,555 lbs; North America; Late Cretaceous
68-66 Million Years Ago; Mesozoic; Tyrannosaurus is an extinct genus of large theropod dinosaur. The species Tyrannosaurus rex, often called T. rex or colloquially T-Rex, is one of the best represented members of the genus as well as all theropods. Tyrannosaurus lived throughout what is now western North America, on what was then an island continent known as Laramidia. Tyrannosaurus had a much wider range than other tyrannosaurids. Fossils are found in a variety of rock formations dating to the Maastrichtian age of the Upper Cretaceous period, 68-66 million years ago. It was the largest and the last known member of the tyrannosaurids and among the last non-avian dinosaurs to exist before the Cretaceous–Paleogene extinction event.