Dakotaraptor (meaning “Dakota Thief”) is a genus of dromaeosaur from the Late Cretaceous of South Dakota in the United States. The specific name is D. steini, named by Robert DePalma in 2015. It was originally found in 2005. At first, this dinosaur seems as if it was a normal dromaeosaurid, but it is three times as large as Velociraptor, at 18 feet (5.5 meters) long. It lived in the Maastrichtian part of the Late Cretaceous in Hell Creek Formation, living alongside Tyrannosaurus. It is closely related to the much smaller Dromaeosaurus. Another Hell Creek Formation dromaeosaur, Acheroraptor, is possibly synonymous with Dakotaraptor, however many scientists believe otherwise due to the fact that the only thing tying the two species together is the similar teeth. Dakotaraptor is also much larger than Acheroraptor.