Utahraptor, which lived during the Early Cretaceous period about 125 million years ago, was the largest known member of the dromaeosaurid (raptor) family, measuring up to 23 feet (7 meters) long and weighing an estimated 600 to 1,000 pounds. First discovered in Utah, USA, in 1991 by paleontologist James Kirkland and officially named Utahraptor ostrommaysi in 1993, this formidable apex predator was characterized by its massive size, a coat of proto-feathers for insulation, and a terrifyingly large, curved 9.5-inch (24 cm) claw on the second toe of each hind foot used to pierce and pin down prey. Unlike its smaller, pop-culture-famous relative Velociraptor, Utahraptor was built much more robustly with thick, powerful leg bones and a heavy skeleton, suggesting it relied on brute strength and ambush tactics rather than lightning speed to hunt large herbivorous dinosaurs like iguanodontians.
