''Daxiatitan'' (; meaning "

Daxia Daxia, Ta-Hsia, or Ta-Hia (; literally: 'Great Xia') was apparently the name given in antiquity by the Han Chinese to Tukhara or Tokhara: the main part of Bactria, in what is now northern Afghanistan, and parts of southern Tajikistan and Uzbek ...

giant" after a tributary of the

Yellow River The Yellow River or Huang He (Chinese: , Standard Beijing Mandarin, Mandarin: ''Huáng hé'' ) is the second-longest river in China, after the Yangtze River, and the List of rivers by length, sixth-longest river system in the world at th ...

) is a

genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In the hierarchy of biological classification, genus com ...

sauropod Sauropoda (), whose members are known as sauropods (; from '' sauro-'' + '' -pod'', 'lizard-footed'), is a clade of saurischian ('lizard-hipped') dinosaurs. Sauropods had very long necks, long tails, small heads (relative to the rest of their bo ...

dinosaur Dinosaurs are a diverse group of reptiles of the clade Dinosauria. They first appeared during the Triassic period, between 243 and 233.23 million years ago (mya), although the exact origin and timing of the evolution of dinosaurs is t ...

known from the

Lower Cretaceous Lower may refer to: *Lower (surname) *Lower Township, New Jersey *Lower Receiver (firearms) *Lower Wick Lower Wick is a small hamlet located in the county of Gloucestershire, England. It is situated about five miles south west of Dursley, eight ...

Gansu Gansu (, ; alternately romanized as Kansu) is a province in Northwest China. Its capital and largest city is Lanzhou, in the southeast part of the province. The seventh-largest administrative district by area at , Gansu lies between the Tibet ...

China China, officially the People's Republic of China (PRC), is a country in East Asia. It is the world's most populous country, with a population exceeding 1.4 billion, slightly ahead of India. China spans the equivalent of five time zones and ...

. Its type and only species is ''Daxiatitan binglingi'' (). It is known from a single partial skeleton consisting of most of the neck and back vertebrae, two tail vertebrae, a

shoulder blade The scapula (plural scapulae or scapulas), also known as the shoulder blade, is the bone that connects the humerus (upper arm bone) with the clavicle (collar bone). Like their connected bones, the scapulae are paired, with each scapula on either ...

, and a

thigh bone The femur (; ), or thigh bone, is the proximal bone of the hindlimb in tetrapod vertebrates. The head of the femur articulates with the acetabulum in the pelvic bone forming the hip joint, while the distal part of the femur articulates wit ...

. At the time of its discovery in 2008, ''Daxiatitan'' was regarded as potentially the largest known dinosaur from China.

Taxonomy

''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 A holotype is a single physical example (or illustration) of an organism, known to have been used when the species (or lower-ranked taxon) was formally described. It is either the single such physical example (or illustration) or one of several ...

of ''D. binglingi'', GSLTZP03-001, was collected from the

Hekou Group The Hekou Group is a geological group in Gansu Province, China. It is Early Cretaceous in age. Dinosaur body fossils have also been recovered from the Hekou Group, including the iguanodont '' Lanzhousaurus'' and the titanosaurs ''Daxiatitan'', ...

, in

Gansu Province Gansu (, ; alternately romanized as Kansu) is a province in Northwest China. Its capital and largest city is Lanzhou, in the southeast part of the province. The seventh-largest administrative district by area at , Gansu lies between the Tibeta ...

, and consists of ten cervical, ten dorsal, and two caudal vertebrae, cervical and dorsal ribs, a haemal arch, a scapulocoracoid, and a femur. The genus name refers to the

Daxia River The Daxia River () is a tributary of the Yellow River in southern Gansu Province in China's west. The Daxia River starts in eastern Huangnan Tibetan Autonomous Prefecture in Qinghai, then flows easterly through northern Gannan Tibetan Autonomo ...

, a tributary of the

that runs through the area where the type specimen was found, and the species name refers to

Bingling Temple The Bingling Temple () is a series of grottoes filled with Buddhist sculpture carved into natural caves and caverns in a canyon along the Yellow River. It lies just north of where the Yellow River empties into the Liujiaxia Reservoir. Administrati ...

, which is located in the region. ''Daxiatitan'' was initially described as a basal

titanosaur Titanosaurs (or titanosaurians; members of the group Titanosauria) were a diverse group of sauropod dinosaurs, including genera from all seven continents. The titanosaurs were the last surviving group of long-necked sauropods, with taxa still th ...

, and most subsequent studies have regarded it as a basal titanosaur or as a somphospondylan close to Titanosauria in

Euhelopodidae Euhelopodidae is a family of sauropod dinosaur Dinosaurs are a diverse group of reptiles of the clade Dinosauria. They first appeared during the Triassic period, between 243 and 233.23 million years ago (mya), although the exact or ...

. In 2020, a phylogenetic analysis conducted by Moore et al. found that ''Daxiatitan'' and ''Euhelopus'' may form a clade with

mamenchisaurids 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. Classification T ...

Description

''Daxiatitan'' was an exceptionally large dinosaur, among the largest known from China. Its length has been estimated as , and its mass has been estimated as 23 tonnes. Like both ''

Euhelopus ''Euhelopus'' is a genus of sauropod dinosaur that lived between 145 and 133 million years ago during the Berriasian and Valanginian stages of the Early Cretaceous in what is now Shandong Province in China. It was a large quadrupedal herbivore. U ...

'' and ''

Huanghetitan ''Huanghetitan'' (meaning "Yellow River titan"), is a genus of sauropod dinosaur from the early Cretaceous Period. It was a basal titanosauriform which lived in what is now Gansu, China. History The type species, ''Huanghetitan liujiaxiaens ...

'', it had an enormously long neck.http://dinogami.smugmug.com/Travel/Dinosaurs-Along-The-Silk-2/8814579_u2jLY#583746852_JEN8b Reconstructing the skeleton of ''Daxiatitan''

Footnotes

References

Early Cretaceous dinosaurs of Asia Titanosaurs Fossil taxa described in 2008 Paleontology in Gansu {{sauropodomorph-stub