Any of a group of related carnivorous dinosaurs similar to the allosaurs .
Tyrannosaurus rex is the largest and best known, found as fossils in Late Cretaceous (99–65 million years ago) deposits of North America and eastern Asia. Some adults were more than 40 ft (12 m) long and 16–18 ft (over 5 m) tall and weighed 6 tons (5.4 metric tons) or more. Tyrannosaurs walked with a stooped posture, carrying the body forward and the long tail off the ground. They had a short, thick neck, a very large skull, and pointed teeth, up to 6 in. (15 cm) long, with serrated edges. Each small forelimb had two claws, perhaps for holding struggling prey. A nearly complete skeleton of T. rex called "Sue" is on display at the Field Museum in Chicago. Other tyrannosaurs include Albertosaurus, Alectrosaurus, and Nanotyrannus .