Atrociraptor is a genus of dromaeosaurid dinosaur that lived during the Late Cretaceous in what is now Alberta, Canada. The first specimen was discovered in 1995 by the fossil collector Wayne Marshall in the Horseshoe Canyon Formation. In 2004, this became the holotype of the new genus and species Atrociraptor marshalli; the generic name is Latin for 'savage robber'. It is estimated to have measured 1.8 to 2 m (5.9 to 6.6 ft) in length and weighed 15 kg (33 lb). It would have had a large sickle-claw on the second toe and pennaceous feathers. Atrociraptor has a deeper face and more strongly backwards inclined teeth than its contemporary relatives. It is thought to have been specialised for attacking larger prey due to its deep snout. Studies suggest dromaeosaurids used their sickle-claws to restrain prey while dismembering them with the mouth. Atrociraptor dates from around 72.2 to 71.5 million years ago; it survived for more than 2 million years and across a wide geographic area. (Full article...)