Dakotaraptor

Dakotaraptor is a possible chimaeric genus of maniraptoriform theropod dinosaur that lived in western North America during the Late Cretaceous period. The remains have been found in the Maastrichtian-aged Hell Creek Formation, dated to the very end of the Mesozoic era, making Dakotaraptor potentially one of the last surviving dromaeosaurids, though other researchers have disputed its classification. One of the largest dromaeosaurids, measuring 4.35–6 m (14.3–19.7 ft) and weighing 220–350 kg (490–770 lb), the remains of D. steini were discovered in a multi-species bonebed. Elements of the holotype and referred specimens were later found to belong to trionychid turtles, and it is unclear whether further analysis of potential non-dromaeosaurid affinities of the holotype and referred material can be properly conducted, because currently the type specimen is housed in a private collection. Phylogenetic analyses of D. steini place it in a variety of positions within Dromaeosauridae.