- "The most terrifying creature on Earth: Utahraptor, a giant, super-sized raptor."
Utahraptor (yoo-tar-rap-tore; meaning "Thief of Utah", or "Utah-thief") is a genus of theropod dinosaurs and is the oldest and largest known member of the theropod dinosaur family Dromaeosauridae (raptor), and dates from the Early Cretaceous period (130-100). Utahraptor is known from a well-preserved skeleton found in 1991 in Utah, USA and fragmentary remains from South America.
Utahraptor lived during the Early Cretaceous period from 130-100 million years ago.
As the largest member of the Dromaeosaur family, Utahraptor stood 6 feet tall, the height of a modern human, measured 24 feet long, almost 4 times as long as it is tall, and weighed in at over 1500 lbs., bigger than a bear. It was the biggest member of its family found, much bigger than its later kin, such as Dromaeosaurus, Deinonychus, and even the more famous Velociraptor. This size was great enough to enable these monstrous raptors the potential to attack, at best, even small Sauropods.
However, just like the later raptor species, one of the most unique aspects that Utahraptor shares with its more famous cousin Velociraptor is that both had a lethal killing claw on each foot. Utahraptor was armed with sickle-like claws on its hind legs and it had self-replenishing teeth in its jaws (and also on its wings.). Thus, these killers were well armed.
Each inside toe had a large (about 9-15 inches) hooked claw that was controlled by a strong tendon. This claw was held upward when the animal was walking or running. When it attacked, however, the tendon snapped tight and the claw clamped down with great speed and force, slicing deeply into its victim. Not a very pretty picture, but an effective way to inflict a serious wound. Its hand claws were proportionally larger than other family members and Dr. Kirkland speculates that its hand claws were probably as important a weapon as the killing claws on its feet.
Like all members of the dromaeosaur family, Utahraptor hunted in packs of at least three.
Hence the name, Utahraptor fossils have been found in Utah. Fossil specimens date to the upper Barremian stage of the early Cretaceous period.