Beishanlong Temporal range: Late Aptian, | |
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Restored skeleton of Beishanlong and Xiongguanlong | |
Scientific classification | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Chordata |
Clade: | Dinosauria |
Clade: | Saurischia |
Clade: | Theropoda |
Clade: | † Ornithomimosauria |
Family: | † Deinocheiridae |
Genus: | † Beishanlong Makovicky et al., 2010 |
Species: | †B. grandis |
Binomial name | |
†Beishanlong grandis Makovicky et al., 2010 | |
Beishanlong is a genus of giant ornithomimosaurian theropod dinosaur from the Early Cretaceous of China. It is the second-largest ornithomimosaur discovered, only surpassed by Deinocheirus.
Three fossils of Beishanlong were found in the early twenty-first century in Northwestern China at the White Ghost Castle site, in the province of Gansu. The type species is Beishanlong grandis, described and named online in 2009 by a team of Chinese and American paleontologists, and formally published in January 2010 by the same Peter Makovicky, Li Daiqing, Gao Keqin, Matthew Lewin, Gregory Erickson and Mark Norrell. The generic name combines a references to the Bei Shan, the "North Mountains", with a Chinese long, "dragon". The specific name means "large" in Latin, in reference to the body size. [1]
Beishanlong lived in the late Aptian stage [2] , with its fossils being uncovered in layers of the Xinminpu Group, in the Xiagou Formation. The holotype is FRDC-GS GJ (06) 01-18, found in 2006, consisting of a partial skeleton lacking the skull. [1] The paratypes consist of two specimens found in 2007: one consisting of remains of hindlimbs, the other, FRDC-GS JB(07)01-01, being a pair of pubes. A fourth fossil found in 1999, IVPP V12756 consisting of foot bones, was tentatively referred to the species. [1]
Beishanlong is of a considerable size, approximating the largest-known individuals of Gallimimus , which have been estimated to reach eight metres. According to the description, Beishanlong "is one of the largest definitive ornithomimosaurs yet described, though histological analysis shows that the holotype individual was still growing at its death." A histological study of the bone structure of the fibula found thirteen or fourteen growth lines, indicating the individual was subadult, though growth had already slowed. [1] The size of this subadult individual is estimated at 5.9–7 m (19–23 ft) in length and 375–626 kilograms (827–1,380 lb) in body mass. [3] [1] [4] [5]
The build of Beishanlong was rather robust. The arms and legs were long, though lacking the extremely elongated hands, feet and claws of later forms. [1]
Beishanlong was by the describers assigned to the Ornithomimosauria, in a more basal position. Beishanlong was closely related to fellow ornithomimosaurian Harpymimus . Together they formed a polytomy with the main ornithomimosaurian branch just below Garudimimus . [1] In 2014 Yuong-Nam Lee et al. recovered Beishanlong as a member of Deinocheiridae basal to a clade containing Garudimimus and Deinocheirus . [6]
Gallimimus is a genus of theropod dinosaur that lived in what is now Mongolia during the Late Cretaceous period, about seventy million years ago (mya). Several fossils in various stages of growth were discovered by Polish-Mongolian expeditions in the Gobi Desert of Mongolia during the 1960s; a large skeleton discovered in this region was made the holotype specimen of the new genus and species Gallimimus bullatus in 1972. The generic name means "chicken mimic", referring to the similarities between its neck vertebrae and those of the Galliformes. The specific name is derived from bulla, a golden capsule worn by Roman youth, in reference to a bulbous structure at the base of the skull of Gallimimus. At the time it was named, the fossils of Gallimimus represented the most complete and best preserved ornithomimid material yet discovered, and the genus remains one of the best known members of the group.
Anserimimus is a genus of ornithomimid theropod dinosaur, from the Late Cretaceous Period of what is now Mongolia. It was a lanky, fast-running animal, possibly an omnivore. From what fossils are known, it probably closely resembled other ornithomimids, except for its more powerful forelimbs.
Ornithomimosauria are theropod dinosaurs which bore a superficial resemblance to the modern-day ostrich. They were fast, omnivorous or herbivorous dinosaurs from the Cretaceous Period of Laurasia, as well as Africa and possibly Australia. The group first appeared in the Early Cretaceous and persisted until the Late Cretaceous. Primitive members of the group include Nqwebasaurus, Pelecanimimus, Shenzhousaurus, Hexing and Deinocheirus, the arms of which reached 2.4 m (8 feet) in length. More advanced species, members of the family Ornithomimidae, include Gallimimus, Struthiomimus, and Ornithomimus. Some paleontologists, like Paul Sereno, consider the enigmatic alvarezsaurids to be close relatives of the ornithomimosaurs and place them together in the superfamily Ornithomimoidea.
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.
Arkansaurus is an extinct genus of ornithomimosaurian theropod dinosaur. It lived during the Albian and Aptian stages of the Early Cretaceous. The type and only species is Arkansaurus fridayi.
Garudimimus is a genus of ornithomimosaur that lived in Asia during the Late Cretaceous. The genus is known from a single specimen found in 1981 by a Soviet-Mongolian paleontological expedition in the Bayan Shireh Formation and formally described in the same year by Rinchen Barsbold; the only species is Garudimimus brevipes. Several interpretations about the anatomical traits of Garudimimus were made in posterior examinations of the specimen, but most of them were criticized during its comprehensive redescription in 2005. Extensive undescribed ornithomimosaur remains at the type locality of Garudimimus may represent additional specimens of the genus.
Archaeornithomimus is a genus of ornithomimosaurian theropod dinosaur that lived in Asia during the Late Cretaceous period, around 96 million years ago in the Iren Dabasu Formation.
Harpymimus is a basal ornithomimosaurian theropod dinosaur from the Early Cretaceous Period of what is now Mongolia. Unlike later, more derived ornithomimosaurs, Harpymimus still possessed teeth, although they appear to have been restricted to the dentary of the lower jaw.
The Bayan Shireh Formation is a geological formation in Mongolia, that dates to the Cretaceous period. It was first described and established by Vasiliev et al. 1959.
Nqwebasaurus is a basal coelurosaur and is the basal-most member of the coelurosaurian clade Ornithomimosauria from the Early Cretaceous of South Africa. The name Nqwebasaurus is derived from the Xhosa word Nqweba which is the local name for the Kirkwood district, and thwazi is ancient Xhosa for "fast runner". Currently it is the oldest coelurosaur in Africa and shows that basal coelurosaurian dinosaurs inhabited Gondwana 50 million years earlier than previously thought. The type specimen of Nqwebasaurus was discovered by William J. de Klerk who is affiliated with the Albany Museum in Grahamstown. It is the only fossil of its species found to date and was found in the Kirkwood Formation of the Uitenhage Group. Nqwebasaurus has the unofficial nickname "Kirky", due to being found in the Kirkwood.
Kinnareemimus is an extinct genus of ornithomimosaurian theropod dinosaur that was discovered in the Early Cretaceous Sao Khua Formation in what is now Thailand. The genus contains only the type species, K. khonkaenensis. The specific epithet is after Khon Kaen Province, which is in northeastern Thailand, where the remains of the animal were dicovered.
The Xiagou Formation is the middle strata of the Xinminbao Group. It is named for its type site in Xiagou, in the Changma Basin of Gansu Province, northwestern China and is considered Early Cretaceous in age. It is known outside the specialized world of Chinese geology as the site of a Lagerstätte in which the fossils were preserved of Gansus yumenensis, the earliest true modern bird.
Deinocheiridae is an extinct family of ornithomimosaurian dinosaurs, living in Asia and the Americas from the Albian until the Maastrichtian. The family was originally named by Halszka Osmólska and Roniewicz in 1970, including only the type genus Deinocheirus. In a 2014 study by Yuong-Nam Lee and colleagues and published in the journal Nature, it was found that Deinocheiridae was a valid family. Lee et al. found that based on a new phylogenetic analysis including the recently discovered complete skeletons of Deinocheirus, the type genus, as well as Garudimimus and Beishanlong, could be placed as a successive group, with Beishanlong as the most primitive and Deinocheirus as most derived. The family Garudimimidae, named in 1981 by Rinchen Barsbold, is now a junior synonym of Deinocheiridae as the latter family includes the type genus of the former. The group existed from 115 to 69 million years ago, with Beishanlong living from 115 to 100 mya, Garudimimus living from 98 to 83 mya, and Deinocheirus living from 71 to 69 mya. Other genera included are Paraxenisaurus, and possibly Harpymimus and Hexing.
Suzhousaurus is a genus of large therizinosauroid dinosaur from the Early Cretaceous of China. The genus is known from two specimens discovered on the Xiagou Formation and Zhonggou Formation—which are situated in the Xinminbao Group. These findings were made during field-works in 1999 and 2004. Though Suzhousaurus is known from these two specimens, an earlier named and described therizinosauroid from the adjacent basin, "Nanshiungosaurus" bohlini, may be synonymous with the former. However, Suzhousaurus can not be compared to this species due to non-overlapping material and the loss of the same. Moreover, this synonymy will result in Suzhousaurus bohlini with "N". bohlini having priority.
Xiongguanlong is an extinct genus of tyrannosauroid theropod from the Early Cretaceous period of what is now China. The type and only species is X. baimoensis. The generic name comes from Jiayuguan City and the Mandarin word "long" which means dragon. The specific epithet, "baimoensis" is a latinization of the Mandarin word for "white ghost" in reference to one of the geological features of the type locality.
Qiupalong is an extinct genus of ornithomimosaurian theropod that was discovered in the Late Cretaceous Qiupa Formation of Henan, China. The genus contains a single species, Q. henanensis, the specific epithet for which was named for the province of Henan. Uniquely, Qiupalong is one of the few Late Cretaceous non-avian dinosaurs known from both Asia and Laramidia. Specimens from Russia and Alberta have been referred to the genus without being assigned to the type species.
This timeline of ornithomimosaur research is a chronological listing of events in the history of paleontology focused on the ornithomimosaurs, a group of bird-like theropods popularly known as the ostrich dinosaurs. Although fragmentary, probable, ornithomimosaur fossils had been described as far back as the 1860s, the first ornithomimosaur to be recognized as belonging to a new family distinct from other theropods was Ornithomimus velox, described by Othniel Charles Marsh in 1890. Thus the ornithomimid ornithomimosaurs were one of the first major Mesozoic theropod groups to be recognized in the fossil record. The description of a second ornithomimosaur genus did not happen until nearly 30 years later, when Henry Fairfield Osborn described Struthiomimus in 1917. Later in the 20th century, significant ornithomimosaur discoveries began occurring in Asia. The first was a bonebed of "Ornithomimus" asiaticus found at Iren Debasu. More Asian discoveries took place even later in the 20th century, including the disembodied arms of Deinocheirus mirificus and the new genus Gallimimus bullatus. The formal naming of the Ornithomimosauria itself was performed by Rinchen Barsbold in 1976.
Aepyornithomimus is a genus of ornithomimid theropod dinosaur from the Late Cretaceous Djadokhta Formation in Mongolia. It lived in the Campanian, around 75 million years ago, when the area is thought to have been a desert. The type and only species is A. tugrikinensis.
Paraxenisaurus is an extinct genus of ornithomimosaurian theropod from the Late Cretaceous Cerro del Pueblo Formation of Coahuila in Mexico. The genus contains a single species, P. normalensis, which is known from a few bones of tail, hips, hands, and feet. The specific epithet was given in honor of the Benemérita Normal School of Coahuila, a teacher training institution, where the fossils were reposited. It is a member of the family Deinocheiridae and is the only member of that clade known from Laramidia.
Oksoko is a genus of oviraptorid dinosaur from the Late Cretaceous of Asia, that lived in what is now the Nemegt Formation in Mongolia. It includes the type species Oksoko avarsan.