Daspletosaurus was an earlier cousin of Tyrannosaurus. This large carnivore could reach 33 feet in length and weigh nearly 4 tons. Far more robust than it's contemporary Gorgosaurus, Daspletosaurus likely hunted heavily armored prey like ceratopsians. Daspletosaurus is known for it's appearance in the documentary Dinosaur Planet and the similarly named Planet Dinosaur. This tyrannosaur lived 75 million years ago in North America.