A carnivorous Utahraptor. With lethal claws, this five-metered killer is well armed and long fingers help them to latch on to swift moving larger prey.
— Allen, describing Utahraptor

Utahraptor (yoo-tar-rap-tore; meaning "Utah Thief") is a genus of large dromeosaurid theropod dinosaur that lived in North America during the Early to Middle Cretaceous period, 130-100 MYA. Utahraptor is known from a well-preserved skeleton found in 1991 in Utah, USA and fragmentary remains from South America.

Measuring 5-8 meters in length, 2-3 meters in height, and 1000 kilograms in weight, Utahraptor was the biggest member of the Dromaeosauridae family found so far, much larger than its later kin, such as the more famous Velociraptor. Their size was great enough to enable these monstrous raptors the potential to attack, at best, even small Sauropods.

Much like the later raptor species, Utahraptor was armed with sickle-like claws on its hind legs and it had self-replenishing teeth in its jaws. Thus, these pack-hunting killers were well armed.



Utahraptor was not only the biggest, but also the oldest known dromaeosaur. Thus, it was the first raptor ever to evolve. It lived during the Early and through out the Middle Cretaceous period from 130–100 million years ago. Hence it's name, it was discovered in the state of Utah and is known from a well-preserved skeleton found in 1991 in Utah, USA and fragmentary remains from South America.


A large dromaeosaurid species notable by their large size, Utahraptor was arguably the largest and strongest dromaeosaur that ever existed. They stood 6 feet (2 m) tall, measured 16.5–24 feet (5–7.4 m) in length, and weighed in at over 1,500 lbs., as heavy as a bear.

Utahraptor had large eyes and long grasping hands with large, sharp ripping claws. Its toe joints were specially enlarged so that its massive claw could be raised upward and backward to avoid damage while running.

But when used in attack, its huge slashing claw flexed forward as the animal kicked out. Swinging in a wide arc its huge 20 cm slashing claw would produce terrible wounds enabling a Utahraptor to cripple and kill animals much larger than itself. With lethal claws, these killers were well armed, and long fingers allowed them to latch onto swift moving, larger prey. Raptors have the short legs of a sprinter and do not pursue their prey for long.

The unique wrist-joints of the dromaeosaurs allowed the hands to pivot sideways, an action similar to the folding of a bird’s wing.



Utahraptor pack eating a dead Iguanodon

Like many predatory dinosaurs and all species of raptors, even Utahraptor hunted in packs; in numbers of up to three individuals at least. Utahraptors were deadly and vicious predators, able to quickly and brutally kill their prey.

They also had a hard time going without a kill for more than over a week. They preferred to stalk and follow their prey unseen under the cover of vegetation and/or darkness, before emerging from their cover and swiftly closing in for the kill.

Whenever they made a kill, they ate as much as 100 kilograms in each sitting and whenever they ate, there was a strict pecking order in their feasts, and the large adults come first, whereas they younger and weaker of the three Utahraptors would be nearby and they would have to wait their turn.