''Yongjinglong'' is an extinct

genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of living and fossil organisms as well as viruses. In the hierarchy of biological classification, genus comes above species and below family. In binomial nom ...

titanosauriform Macronaria is a clade of sauropod dinosaurs. Macronarians are named after the large diameter of the nasal opening of their skull, known as the external naris, which exceeded the size of the orbit, the skull opening where the eye is located (hence ...

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 origin and timing of the evolution of dinosaurs is t ...

known from the Early Cretaceous of Lanzhou-Minhe Basin of

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 ...

, China. It contains a single species, ''Yongjinglong datangi''.

Discovery

''Yongjinglong'' was first described and named by Li-Guo Li, Da-Qing Li, Hai-Lu You and

Peter Dodson Peter Dodson (born August 20, 1946) is an American paleontologist who has published many papers and written and collaborated on books about dinosaurs. An authority on Ceratopsians, he has also authored several papers and textbooks on hadrosaurs a ...

2014 File:2014 Events Collage.png, From top left, clockwise: Stocking up supplies and personal protective equipment (PPE) for the Western African Ebola virus epidemic; Citizens examining the ruins after the Chibok schoolgirls kidnapping; Bundles of wat ...

and the

type species In zoological nomenclature, a type species (''species typica'') is the species name with which the name of a genus or subgenus is considered to be permanently taxonomically associated, i.e., the species that contains the biological type specime ...

is ''Yongjinglong datangi''. The generic name is derived from the name of the historical

Yongjing County Yongjing (, Xiao'erjing: ) is a county in Linxia Hui Autonomous Prefecture in China's Gansu Province. The county seat, the town (''zhen'') of Liujiaxia (), is located about 80 km south-west from the provincial capital city, Lanzhou. As is t ...

, near where 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 sever ...

of ''Yongjinglong'' and numerous dinosaur track fossils were collected, and from ''long'', meaning " dragon" in

Chinese Chinese can refer to: * Something related to China * Chinese people, people of Chinese nationality, citizenship, and/or ethnicity **''Zhonghua minzu'', the supra-ethnic concept of the Chinese nation ** List of ethnic groups in China, people of ...

. The specific name, ''datangi'', honors the

Tang dynasty The Tang dynasty (, ; zh, t= ), or Tang Empire, was an imperial dynasty of China that ruled from 618 to 907 AD, with an interregnum between 690 and 705. It was preceded by the Sui dynasty and followed by the Five Dynasties and Ten Kingdom ...

and also Mr. Zhi-Lu Tang from the IVPP, for his contributions to the study of

s. ''Yongjinglong'' is known solely from the

GSGM ZH(08)-04, a partial

postcrania Postcrania (postcranium, adjective: postcranial) in zoology and vertebrate paleontology is all or part of the skeleton apart from the skull. Frequently, fossil remains, e.g. of dinosaurs or other extinct tetrapods, consist of partial or isolated sk ...

l skeleton and three

teeth A tooth ( : teeth) is a hard, calcified structure found in the jaws (or mouths) of many vertebrates and used to break down food. Some animals, particularly carnivores and omnivores, also use teeth to help with capturing or wounding prey, t ...

, currently housed at the Gansu Geological Museum,

. The postcranial remains include one fragmentary dorsal rib, the left

scapulocoracoid The scapulocoracoid is the unit of the pectoral girdle that contains the coracoid and scapula. The coracoid itself is a beak-shaped bone that is commonly found in most vertebrates with a few exceptions. The scapula is commonly known as the ''shoulde ...

, the right

ulna The ulna (''pl''. ulnae or ulnas) is a long bone found in the forearm that stretches from the elbow to the smallest finger, and when in anatomical position, is found on the medial side of the forearm. That is, the ulna is on the same side of t ...

and

radius In classical geometry, a radius ( : radii) of a circle or sphere is any of the line segments from its center to its perimeter, and in more modern usage, it is also their length. The name comes from the latin ''radius'', meaning ray but also the ...

, as well as eight presacral

vertebrae The spinal column, a defining synapomorphy shared by nearly all vertebrates, Hagfish are believed to have secondarily lost their spinal column is a moderately flexible series of vertebrae (singular vertebra), each constituting a characteristi ...

including one caudal

cervical vertebra In tetrapods, cervical vertebrae (singular: vertebra) are the vertebrae of the neck, immediately below the skull. Truncal vertebrae (divided into thoracic and lumbar vertebrae in mammals) lie caudal (toward the tail) of cervical vertebrae. In sa ...

, four cranial

dorsal vertebrae In vertebrates, thoracic vertebrae compose the middle segment of the vertebral column, between the cervical vertebrae and the lumbar vertebrae. In humans, there are twelve thoracic vertebrae and they are intermediate in size between the cervical ...

, and three articulated middle dorsal vertebrae. It represents a subadult individual. GSGM ZH(08)-04 was by Li Daqing and You Hailu discovered in 2008 beside the G75 Highway, less than a

kilometer The kilometre ( SI symbol: km; or ), spelt kilometer in American English, is a unit of length in the International System of Units (SI), equal to one thousand metres (kilo- being the SI prefix for ). It is now the measurement unit used for ex ...

from the quarries of ''

Daxiatitan ''Daxiatitan'' (; meaning "Daxia giant" after a tributary of the Yellow River) is a genus of sauropod dinosaur known from the Lower Cretaceous of Gansu, China. Its type and only species is ''Daxiatitan binglingi'' (). It is known from a single p ...

'' and '' Huanghetitan liujiaxiaensis'', near Zhongpu. It was collected from the upper

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 the southeastern part of the Lanzhou-Minhe Basin,

, dating to the Early Cretaceous.

Description

''Yongjinglong'' was a medium-sized sauropod. The describers established some diagnostic traits. The premaxillary teeth are long and spoon-shaped. The neck vertebrae and anterior dorsal vertebrae possess large and deep pleurocoels, pneumatic depressions, that cover the entire sides of the centra. The ridges on the sides of the middle dorsal vertebrae form a pattern shaped like a "XI", with the "X" in front. The spine of at least one middle dorsal vertebra is low and not bifurcated and forms with the postzygapophyses a triangular bone plate, directed upwards. The shoulder blade is extremely long, with, in side view, exceptionally straight front and rear edges.

Phylogeny

''Yongjinglong'' was placed in the

Titanosauria 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 thr ...

by Li ''et al.'' (2014). Their

cladistic Cladistics (; ) is an approach to biological classification in which organisms are categorized in groups ("clades") based on hypotheses of most recent common ancestry. The evidence for hypothesized relationships is typically shared derived char ...

analysis showed it was a member of the

Somphospondyli Somphospondyli is an extinct clade of titanosauriform sauropods that lived from the Late Jurassic until the end of the Late Cretaceous, comprising all titanosauriforms more closely related to Titanosauria proper than Brachiosauridae. The remains ...

and a

sister species In phylogenetics, a sister group or sister taxon, also called an adelphotaxon, comprises the closest relative(s) of another given unit in an evolutionary tree. Definition The expression is most easily illustrated by a cladogram: Taxon A and ...

of ''

Opisthocoelicaudia ''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 wa ...

''. However, a 2019 revision of Chinese "titanosaurs" resolved ''Yongjinglong'' deeply nested within

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 ...

, sister taxon to ''

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 ...

'' and ''

Ruyangosaurus ''Ruyangosaurus'' (Ruyang County lizard) 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''. Descri ...

'', or a clade including ''

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 ...

'', ''

Erketu ''Erketu'' (meaning "Erketü Tengri") is a genus of somphospondylan sauropod dinosaur that lived in Asia during the Late Cretaceous roughly between 96 million and 89 million years ago. Its fossils were found in Mongolia between 2002 and 2003 du ...

'' and ''

Gobititan ''Gobititan'' is a genus of herbivorous sauropod dinosaur from the Aptian faunal stage of the Early Cretaceous. The name of this genus is derived from the Gobi desert region and the Titans of Greek mythology, which is a reference to its large ...

''.

References

{{Taxonbar, from=Q15690935 Early Cretaceous dinosaurs of Asia Fossil taxa described in 2014 Titanosaurs Taxa named by Peter Dodson Paleontology in Gansu