Deinonychus

Deinonychus antirrhopus is a genus of dromaeosaurid theropod dinosaur. It lived during the early Cretaceous Period, about 115–108 million years ago. Fossils have been recovered from the U.S. states of Montana, Utah, Wyoming, and Oklahoma. The species name means ‘counter balance’, which refers to Ostrom’s idea about the function of the tail.