Other independent analysis, specifically proposed by Andrea Cau, put forth suspicions that some of the caudal material might in fact belong to ornithomimid material, and that the large ungual of Dakotaraptor might instead be a Tyrannosaurus claw. Additionally, it has been proposed the leg bones attributed to the holotype might even belong to an oviraptorosaur instead, likely Anzu, which raise the question about the chimeric nature of the holotype. The wishbones could easily be removed from the type fossil definition, maintaining the validity of the genus. However, this is dubious at best, as there may be new papers confirming that Dakotaraptor was indeed a valid genus. If this was true, Dakotaraptor would've no longer have been a valid genus, and merely a chimaera between a theropod dinosaur and a turtle. An even more recent phylogenetic analysis recovers Dakotaraptor as a dromaeosaurine, though its questionable chimeric nature is raised to the debate.ĭakotaraptor is the second dromaeosaurid dinosaur known from the Hell Creek Formation, with the first being the much smaller Acheroraptor. The only other mainly predatory dinosaur known to have been around at the same time and location, while being bigger than Dakotaraptor, is the mighty Tyrannosaurus. Possible prey dinosaurs for Dakotaraptor could include anything from ceratopsian dinosaurs such as Triceratops, ankylosaurs and nodosaurs such as Ankylosaurus and Denversaurus, pachycephalosaurs such as Pachycephalosaurus, and hadrosaurs and thescelosaurs such as Anatosaurus and Thescelosaurus.Ī recent study seemed to show that the wishbones of Dakotaraptor may actually belong to an extinct genus of turtles: Axestemys splendida. This analysis is still under reviewing, but it is to note the position of Dakotaraptor as a dromaeosaur in general is still very solid. More recent analysis, by Hartman et al, defy the original views that Dakotaraptor was a dromaeosaurine, and cladistic analysis go to the notion that it was instead an unusual large unenlagiine, which would make it the first North American member of the Unenlagiinae. It has been considered as being a closer relative to the Campanian Dromaeosaurus (having been classified as its sister taxon, therefore making them most closely related to each other), so Dakotaraptor's large size is only an example of convergent evolution with Utahraptor. This is also consistent with the time that spans between Utahraptor and Dakotaraptor. Curiously, Dakotaraptor was more gracile, and had a lighter build more akin to those of these smaller dromaeosaurids than to Utahraptor. The fossils discovered in South Dakota show tiny “quill knobs” on the lower arm bones, suggesting Dakotaraptor had feathers all over the body, including wings on its arms.Ī study of the known fossils of Dakotaraptor show that in body proportions this genus was actually more like genera such as Deinonychus and Dromaeosaurus than to those of Utahraptor, making a direct link between Dakotaraptor and Utahraptor unlikely. Utahraptor has a max estimation of 7 metres (23 ft) in length and 500 kg (1,100 lbs) in weight, while Dakotaraptor was 5.5 metres (19.6 ft) in length and 453 kg (1,000 lbs) in weight but were on a similar scale. A common misconception is that Dakotaraptor has beaten Utahraptor as the largest dromaeosaurid, but this is untrue.
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