Gorgosaurus (Latin for "fierce lizard") is a genus of carnivorous dinosaur that reached 8 to 9 meters (26 to 30 feet) in length, and weighed 2.5-3 tonnes. It was first described by paleontologist Lawrence Morris Lambe in 1914, and has been found in western Canada and the United States. It lived about 70-65 million years ago in the late Cretaceous period.
Over 20 Gorgosaurus skeletons have been recovered, making it the most well-represented tyrannosaurid in the fossil record. Generally similar to Tyrannosaurus and most other large tyrannosaurids (such as Daspletosaurus, and Albertosaurus), Gorgosaurus can be described as having a massive head, large, curved teeth, tiny two-fingered front limbs, and powerful legs. Compared to the other tyrannosaurids, Gorgosaurus is most similar to its very close relative Albertosaurus.
Although it has been suggested that Gorgosaurus was a scavenger, its co-existence with the similarly sized, but more robust tyrannosaurid Daspletosaurus casts doubt on this theory. Another hypothesis proposes that Gorgosaurus, which was rather lean for a tyrannosaurid, actively hunted fleet-footed animals such as duckbills and ornithomimids ("ostrich-mimic" dinosaurs). According to this proposition, the more troublesome ceratopsians and ankylosaurians (horned and heavily armoured dinosaurs) would have been left to Daspletosaurus. An apex predator, it was at the top of the food chain.
For years, the species Gorgosaurus libratus (the only species of Gorgosaurus currently recognized) was assigned to the Albertosaurus genus. However, recent work done by paleontologists suggest that enough differences exist between G. libratus and the other Albertosaurus species, to justify the original genus name of Gorgosaurus.
In The Land Before Time
A skeleton of Gorgosaurus briefly appears in The Land Before Time XII: The Great Day of the Flyers, where it is briefly encountered by Guido in The Mysterious Beyond.