Utahraptor ostrommaysi YOO-tah-RAP-tor
"Utah's thief"
You 1.8 m (5.9 ft) tall
Utahraptor 6 m (19.7 ft) long
4 people holding hands
- Length
- 6 m (19.7 ft) — About 6 m long, ~500 kg — the largest dromaeosaur ever found.
- Period
- Early Cretaceous (126–124 Mya)
- Place
- North America · Utah
- Food
- Carnivore — Large prey — iguanodontians, juvenile sauropods, anything it could pin down.
Utahraptor was the giant of the dromaeosaur family — about the size of a polar bear and built like a bird of prey scaled up to bear weight. Its discovery in 1991, right when Jurassic Park was in production, changed how filmmakers imagined raptors. A massive sandstone block found in Utah preserves at least six Utahraptors that may have been mired together in quicksand.
What we know
- Sickle claw on the second toe was nearly 24 cm long — the largest known among dromaeosaurs.
- Heavily built compared to other raptors, with thicker bones to support the larger body.
- A massive sandstone block from Utah preserves multiple individuals stuck together — the 'Utahraptor megablock'.
- Lived about 60 million years before Velociraptor.
What we guess
- Whether the bonebed represents pack hunting or just multiple animals trapped by the same death trap.
- Color and feather pattern — almost certainly feathered, but no preserved feathers have been found yet.
- How it brought down prey much larger than itself — the leading idea is the 'raptor prey restraint' model.