Daxiatitan Temporal range: Lower Cretaceous, | |
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Mounted skeleton cast | |
Scientific classification ![]() | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Chordata |
Clade: | Dinosauria |
Clade: | Saurischia |
Clade: | † Sauropodomorpha |
Clade: | † Sauropoda |
Clade: | † Macronaria |
Clade: | † Titanosauria |
Genus: | † Daxiatitan You et al., 2008 |
Species: | †D. binglingi |
Binomial name | |
†Daxiatitan binglingi You et al., 2008 | |
Daxiatitan [a] is a genus of sauropod dinosaur known from the Lower Cretaceous of Gansu, China. Its type and only species is Daxiatitan binglingi. [b] It is known from a single partial skeleton consisting of most of the neck and back vertebrae, two tail vertebrae, a shoulder blade, and a thigh bone. At the time of its discovery in 2008, Daxiatitan was regarded as potentially the largest known dinosaur from China. [1]
Daxiatitan and its type and only species Daxiatitan binglingi were named by You Hailu, Li Daqing, Zhou Lingqi, and Ji Qiang in 2008. The holotype of D. binglingi, GSLTZP03-001, was collected from the Hekou Group, in Gansu Province, and consists of ten cervical, ten dorsal, and two caudal vertebrae, cervical and dorsal ribs, a haemal arch, a scapulocoracoid, and a femur. [1]
The genus name refers to the Daxia River, a tributary of the Yellow River that runs through the area where the type specimen was found, and the species name refers to Bingling Temple, which is located in the region. [1]
Daxiatitan was initially described as a basal titanosaur, [1] and most subsequent studies have regarded it as a basal titanosaur or as a somphospondylan close to Titanosauria in Euhelopodidae. In 2020, a phylogenetic analysis conducted by Moore et al. found that Daxiatitan and Euhelopus may form a clade with mamenchisaurids. [2]
Daxiatitan was an exceptionally large dinosaur, among the largest known from China. [1] Its length has been estimated as 23–30 meters (75–98 ft), [c] and its mass has been estimated as 23 tonnes. [4] The neck of Daxiatitan is estimated to have been approximately 12 metres (39 ft) long, [d] making it among the longer-necked sauropods, although still surpassed by the 15-meter neck of some of the largest mamenchisaurids and diplodocids. [5]
Mamenchisaurus is a genus of sauropod dinosaur known for their remarkably long necks which made up nearly half the total body length. Numerous species have been assigned to the genus; however, the validity of these assignments has been questioned. Fossils have been found in the Sichuan Basin and Yunnan Province in China. Several species from the Upper Shaximiao Formation, whose geologic age is uncertain, have been described. However, evidence suggests this formation to be no earlier than the Oxfordian stage of the Late Jurassic. M. sinocanadorum dates to the Oxfordian stage, and M. anyuensis to the Aptian stage of the Early Cretaceous. Most species were medium-large to large sauropods, measuring roughly 15 to 26 meters in length—possibly up to 35 meters (115 ft), based on two undescribed vertebrae.
Opisthocoelicaudia is a genus of sauropod dinosaur of the Late Cretaceous Period discovered in the Gobi Desert of Mongolia. The type species is Opisthocoelicaudia skarzynskii. A well-preserved skeleton lacking only the head and neck was unearthed in 1965 by Polish and Mongolian scientists, making Opisthocoelicaudia one of the best known sauropods from the Late Cretaceous. Tooth marks on this skeleton indicate that large carnivorous dinosaurs had fed on the carcass and possibly had carried away the now-missing parts. To date, only two additional, much less complete specimens are known, including part of a shoulder and a fragmentary tail. A relatively small sauropod, Opisthocoelicaudia measured about 11.4–13 m (37–43 ft) in length. Like other sauropods, it would have been characterised by a small head sitting on a very long neck and a barrel shaped trunk carried by four column-like legs. The name Opisthocoelicaudia means "posterior cavity tail", alluding to the unusual, opisthocoel condition of the anterior tail vertebrae that were concave on their posterior sides. This and other skeletal features lead researchers to propose that Opisthocoelicaudia was able to rear on its hindlegs.
Euhelopus is a genus of sauropod dinosaur that lived between 145 and 133 million years ago during the Berriasian and Valanginian ages of the Early Cretaceous in what is now Shandong Province in China. It was a large quadrupedal herbivore. Like sauropods such as brachiosaurs and titanosaurs, Euhelopus had longer forelegs than hind legs. This discovery was paleontologically significant because it represented the first dinosaur scientifically investigated from China: seen in 1913, rediscovered in 1922, and excavated in 1923 and studied by T'an during the same year. Unlike most sauropod specimens, it has a relatively complete skull.
Bellusaurus was a small short-necked sauropod dinosaur from the Late Jurassic (Oxfordian) which measured about 4.8 metres (16 ft) long. Its fossils were found in Shishugou Formation rocks in the northeastern Junggar Basin in China.
Daanosaurus was a genus of dinosaur. It was a sauropod which lived during the Late Jurassic. It lived in what is now China, and was similar to Bellusaurus.
Hudiesaurus is a herbivorous sauropod genus of dinosaur from China. Its fossil remains were found in 1993 by a Chinese-Japanese expedition near Qiketai in Shanshan, Xinjiang province. The genus contains a single species, Hudiesaurus sinojapanorum, was named and described by Dong Zhiming in 1997. The generic name is derived from Mandarin hudie, meaning "butterfly," and refers to a flat butterfly-shaped process on the front base of the vertebral spine. The specific name refers to the members of the Sino-Japan Silk Road Dinosaur Expedition but can also be read as "central part" in Chinese, a pun on the Japanese Chunichi Shimbun press group, which financed the research.
Klamelisaurus is a genus of herbivorous sauropod dinosaur from the Middle Jurassic Shishugou Formation of China. The type species is Klamelisaurus gobiensis, which was named by Zhao Xijin in 1993, based on a partial skeleton discovered in 1982 near the abandoned town of Jiangjunmiao. Zhao described Klamelisaurus as the only member of a new subfamily, Klamelisaurinae, among the now-defunct primitive sauropod order Bothrosauropodoidea. Since Zhao's description, Klamelisaurus received limited attention from researchers until Andrew Moore and colleagues redescribed it in 2020.
Yuanmousaurus was a sauropod dinosaur from the Middle Jurassic period of China. It is known from incomplete remains, recovered in 2000 from the Zhanghe Formation in Yuanmou County in Yunnan Province. Yuanmousaurus was a relatively large sauropod and may have reached about 17 meters (56 ft) in length. It was a basal member of the Sauropoda, but its exact systematic position is unclear. A recent study placed Yuanmousaurus within the family Mamenchisauridae. It may be a dubious genus. The only and type species was Yuanmousaurus jiangyiensis.
Phuwiangosaurus is a genus of titanosaur dinosaur from the Early Cretaceous (Valanginian-Hauterivian) Sao Khua Formation of Thailand. The type species, P. sirindhornae, was described by Martin, Buffetaut, and Suteethorn in a 1993 press release and was formally named in 1994. The species was named to honor Princess Maha Chakri Sirindhorn of Thailand, who was interested in the geology and palaeontology of Thailand, while the genus was named after the Phu Wiang area, where the fossil was discovered. The precise affinities of Phuwiangosaurus among titanosauriform sauropods are uncertain, though several studies have classified it as a euhelopodid.
Puertasaurus is a genus of sauropod dinosaur that lived in South America during the Late Cretaceous Period. It is known from a single specimen recovered from sedimentary rocks of the Cerro Fortaleza Formation in southwestern Patagonia, Argentina, which probably is Campanian or Maastrichtian in age. The only species is Puertasaurus reuili. Described by the paleontologist Fernando Novas and colleagues in 2005, it was named in honor of Pablo Puerta and Santiago Reuil, who discovered and prepared the specimen. It consists of four well-preserved vertebrae, including one cervical, one dorsal, and two caudal vertebrae. Puertasaurus is a member of Titanosauria, the dominant group of sauropods during the Cretaceous.
Euhelopodidae is a family of sauropod dinosaurs of disputed membership and affinities, which contains Euhelopus and its close relatives. Most proposed euhelopodids are from East Asia.
Camarasauridae is a family of sauropod dinosaurs. Among sauropods, camarasaurids are small to medium-sized, with relatively short necks. They are visually identifiable by a short skull with large nares, and broad, spatulate teeth filling a thick jaw. Based on cervical vertebrae and cervical rib biomechanics, camarasaurids most likely moved their necks in a vertical, rather than horizontal, sweeping motion, in contrast to most diplodocids.
Mamenchisauridae is a family of sauropod dinosaurs belonging to Eusauropoda known from the Jurassic and Early Cretaceous of Asia and Africa. Some members of the group reached gigantic sizes, amongst the largest of all sauropods.
Ruyangosaurus is a genus of titanosauriform sauropod dinosaur recovered from the Early Cretaceous Haoling Formation of China. The type species is R. giganteus, described in 2009 by Lü Junchang et al.
Xianshanosaurus is a genus of sauropod dinosaur from the Early Cretaceous (Aptian-Albian) of the Ruyang Basin in Henan Province, China. Its type and only species is Xianshanosaurus shijiagouensis. It was described in 2009 by a team of paleontologists led by Lü Junchang. Xianshanosaurus may be a titanosaur, and Daxiatitan may be its closest relative, but its evolutionary relationships remain controversial.
Xinjiangtitan is an extinct genus of mamenchisaurid sauropod that lived during the Middle Jurassic of what is now Xinjiang, northwestern China. Its type and only species is Xinjiangtitan shanshanesis, known from a single incomplete skeleton recovered from the Qiketai Formation. The holotype preserves one of the most complete vertebral columns of any sauropod found in Asia, and has the longest complete neck known for any animal.
Yongjinglong is an extinct genus of titanosauriform sauropod dinosaur known from the Early Cretaceous of Lanzhou-Minhe Basin of Gansu Province, China. It contains a single species, Yongjinglong datangi.
Fushanosaurus is a genus of sauropod dinosaur from the Shishugou Formation from Xinjiang Province in China. The type and only species is Fushanosaurus qitaiensis. It is solely known from the holotype specimen FH000101, a complete right femur.
Rhomaleopakhus is a genus of mamenchisaurid sauropod, dinosaur from the Late Jurassic Kalaza Formation of China. The type and only species is Rhomaleopakhus turpanensis.
Ruixinia is an extinct genus of somphospondylan titanosauriform dinosaur from the Early Cretaceous (Barremian) Yixian Formation of China. The genus contains a single species, Ruixinia zhangi. The Ruixinia holotype is a partial articulated skeleton with the most complete series of caudal vertebrae known from any Asian titanosauriform.