Gorgosaurus fossil map
Where fossils of Gorgosaurus have been found, shown on the Earth as it looked about 75 million years ago and on today’s map.
Dots are fossil collections recorded in the Paleobiology Database. The “then” view moves today’s fossil sites back to their positions 75 million years ago (the time slice nearest the median age of the fossils) using the Merdith et al. (2021) plate model; positions are approximate. Open on the timeline map →
| Group | Theropods |
|---|---|
| Lived | 83.6–66 million years ago (Campanian to Maastrichtian) |
| Periods | Cretaceous |
| Family | Tyrannosauridae |
| Named by | Lambe 1914 |
| Fossil records | 20 occurrences at 18 locations (PBDB) |
| Found in | Canada, United States |
| Rock formations | Dinosaur Park, Hell Creek, Judith River, txn:38606, Sedan, Oldman |
About Gorgosaurus
Gorgosaurus ( GOR-gə-SOR-əs; lit. 'dreadful lizard') is a genus of tyrannosaurid theropod dinosaur that lived in western North America during the Late Cretaceous Period (Campanian), between about 76.5 and 73 million years ago. Fossil remains have been found in Western Canada as well as the U.S. state of Montana. Paleontologists recognize only the type species, G. libratus, although other species have been erroneously referred to the genus.
Like most known tyrannosaurids, Gorgosaurus was a large bipedal predator, measuring 8–9 metres (26–30 ft) in length and 2–3 metric tons (2.2–3.3 short tons) in body mass. Dozens of large, sharp teeth lined its jaws, while its two-fingered forelimbs were comparatively small. Gorgosaurus was most closely related to Albertosaurus, and more distantly related to the larger Tyrannosaurus. Gorgosaurus and Albertosaurus are extremely similar, distinguished mainly by subtle differences in the teeth and skull bones. Some experts consider G. libratus to be a species of Albertosaurus; this would make Gorgosaurus a junior synonym of that genus.
Text in “About” is quoted from the Wikipedia article Gorgosaurus (revision 1380988908), licensed under CC BY-SA 4.0; introduction excerpted verbatim, formatting removed. Ages, family, authority and fossil records: Paleobiology Database, accessed 22 October 2026. Ages are those of the rock layers the fossils were found in. Wikidata: Q40752.
