A new species of giant that measured about 17 feet long was discovered in South Dakota.

The beast, dubbed the Dakotaraptor, was one of the largest raptors to ever walk the Earth and is the first giant dromaeosaur ever discovered in the region, the University of Kansas reported.

"Most dromaeosaurids were small- to medium-sized cursorial, scansorial, and arboreal, sometimes volant predators, but a comparatively small percentage grew to gigantic proportions. Only two such giant "raptors" have been described from North America," the researchers wrote in the study abstract.

The fascinating specimen was discovered in South Dakota's Hell Creek Formation by an expedition team led by Robert DePalma, curator of vertebrate paleontology at the Palm Beach Museum of Natural History and lead author of the research. The fossil fills in an important gap in the fossil record.

"This new predatory dinosaur also fills the body size gap between smaller theropods and large tyrannosaurs that lived at this time," said KU Paleontologist and co-author David Burnham.

"This Cretaceous period raptor would have been lightly built and probably just as agile as the vicious smaller theropods, such as the Velociraptor," De Palma continued.

The researchers spotted ulnar papilli, or "quill knobs," on the ancient specimen. This suggests the raptor had feather quills on its forearms. The discovery of these quills could provide insight into the evolution of flight-related features. Flightless evolution may have evolved several times in this lineage, as raptors transitioned into the birds we see today.

"The presence of this new predator expands our record of theropod diversity in latest Cretaceous Laramidia, and radically changes paleoecological reconstructions of the Hell Creek Formation," the researchers wrote.

The findings were published in a recent edition of the journal Paleontological Contributions.