page_title: Deinocheirus
section_title: Discovery
hierarchical_section_title: Deinocheirus / Discovery
caption_attribution_description: English: Map of Cretaceous-aged dinosaur fossil localities of Mongolia. Gobihadros mongoliensis was collected from Bayshin Tsav in Area C. Open squares indicate Late Cretaceous sites, solid squares represent Early Cretaceous localities. Abbreviations: A, Localities of Western Gobi Desert in Mongolia, mainly group of localities of Nemegtian age (early Maastrichtian), Late Cretaceous; B, Localities of Central Gobi Desert in Mongolia, mainly Djadokhtian age (Campanian), Late Cretaceous; C &amp; D- Localities of Eastern Gobi Desert in Mongolia, mainly Baynshirenian age (Cenomanian-Santonian), Late Cretaceous. Figure has been modified from Tsogtbaatar et al. 2014, Figure 1 [24].
context_page_description: Deinocheirus is a genus of large ornithomimosaur that lived during the Late Cretaceous around 70 million years ago. In 1965, a pair of large arms, shoulder girdles, and a few other bones of a new dinosaur were first discovered in the Nemegt Formation of Mongolia. In 1970, this specimen became the holotype of the only species within the genus, Deinocheirus mirificus; the genus name is Greek for "horrible hand". No further remains were discovered for almost fifty years, and its nature remained a mystery. Two more complete specimens were described in 2014, which shed light on many aspects of the animal. Parts of these new specimens had been looted from Mongolia some years before, but were repatriated in 2014.
  Deinocheirus was an unusual ornithomimosaur, the largest of the clade at 11 m long, and weighing 6.4 t. Though it was a bulky animal, it had many hollow bones which saved weight. The arms were among the largest of any bipedal dinosaur at 2.4 m long, with large, blunt claws on its three-fingered hands. The legs were relatively short, and bore blunt claws. Its vertebrae had tall neural spines that formed a "sail" along its back.
context_section_description: The first known fossil remains of Deinocheirus were discovered by Polish palaeontologist Zofia Kielan-Jaworowska on July 9, 1965, at the Altan Ula III site (coordinates: 43°33.987′N 100°28.959′E) in the Nemegt Basin of the Gobi Desert. She was part of a Polish group accompanied by Mongolian palaeontologist Rinchen Barsbold during the 1963–1965 Polish-Mongolian palaeontological expeditions, which were organised by the Polish Academy of Sciences and the Mongolian Academy of Sciences. The crew spent July 9–11 excavating the specimen and loading it onto a vehicle. A 1968 report by Kielan-Jaworowska and Naydin Dovchin, which summarised the accomplishments of the expeditions, announced that the remains represented a new family of theropod dinosaur. The specimen was discovered on a small hill in sandstone, and consists of a partial, disarticulated skeleton, most parts of which had probably eroded away at the time of discovery. The specimen consisted of both forelimbs, excluding the claws of the right hand, the complete shoulder girdle, centra of three dorsal vertebrae, five ribs, gastralia (belly ribs), and two ceratobranchialia. The specimen was made the holotype of Deinocheirus mirificus, named by Halszka Osmólska and Ewa Roniewicz in 1970. The generic name is derived from Greek deinos (δεινός), meaning "horrible", and cheir (χείρ), meaning "hand", due to the size and strong claws of the forelimbs. The specific name comes from Latin and means "unusual" or "peculiar", chosen for the unusual structure of the forelimbs. The Polish-Mongolian expeditions were notable for being led by women, among the first to name new dinosaurs. The original specimen number of the holotype was ZPal MgD-I/6, but it has since been re-catalogued as MPC-D 100/18.
  The paucity of known Deinocheirus remains inhibited a thorough understanding of the animal for almost half a century onwards, and the scientific literature often described it as among the most "enigmatic", "mysterious", and "bizarre" of dinosaurs. The holotype arms became part of a traveling exhibit of Mongolian dinosaur fossils, touring various countries. In 2012, Phil R. Bell, Philip J. Currie, and Yuong-Nam Lee announced the discovery of additional elements of the holotype specimen, including fragments of gastralia, found by a Korean-Mongolian team which re-located the original quarry in 2008. Bite marks on two gastralia were identified as belonging to Tarbosaurus, and it was proposed that this accounted for the scattered, disassociated state of the holotype specimen.
  In 2013, the discovery of two new Deinocheirus specimens was announced before the annual Society of Vertebrate Paleontology (SVP) conference by Lee, Barsbold, Currie, and colleagues. Housed at the Mongolian Academy of Sciences, these two headless individuals were given the specimen numbers MPC-D 100/127 and MPC-D 100/128. MPC-D 100/128, a subadult specimen, was found by scientists in the Altan Ula IV locality (coordinates: 43°36.091′N 100°27.066′E) of the Nemegt Formation during the Korea-Mongolia International Dinosaur Expedition in 2006, but had already been damaged by fossil poachers. The second specimen, MPC-D 100/127, was found by scientists in the Bugiin Tsav locality (coordinates: 43°54.025′N 99°58.359′E) in 2009. It is slightly larger than the holotype, and it could be clearly identified as Deinocheirus by its left forelimb, and therefore helped identify the earlier collected specimen as Deinocheirus. The specimen had also been excavated by poachers, who had removed the skull, hands and feet, but left behind a single toe bone. It had probably been looted after 2002, based on money left in the quarry. Skulls, claw bones and teeth are often selectively targeted by poachers on the expense of the rest of the skeletons (which are often vandalized), due to their saleability. Currie stated in an interview that it was a policy of their team to investigate quarries after they had been looted and recover anything of significance, and that finding any new Deinocheirus fossils was cause for celebration, even without the poached p
caption: Cretaceous-aged dinosaur fossil localities of Mongolia; Deinocheirus fossils have been collected in the Altan Ula III, IV, and Bugiin Tsav localities of area A (left)
exif: {}