Temporal range: Early Cretaceous
Kirkland, Gaston & Burge, 1993
U. ostrommaysorum (Kirkland, Gaston & Burge, 1993) (type)
It was a fast-moving, agile, bipedal (walked on two legs), bird-like dinosaur. It had a curved, flexible neck and a big head. Sharp, serrated teeth were set into very powerful jaws. Each of its three fingers on each arm had large, sharp, curved claw.
It had four-toed feet; the second toe had a 9-15 inch (23-38 cm) sickle-like claw and the other toes had smaller claws. Its long tail had bony rods running along the spine giving it rigidity; the tail was used for balance and fast turning ability.
It had a relatively large brain and large, keen, eyes. Utahraptor was 16-23 feet (5-7 m) long and may have weighed about .5 ton.