Nanshiungosaurus
Encyclopedia
Nanshiungosaurus is a genus
Genus
In biology, a genus is a low-level taxonomic rank used in the biological classification of living and fossil organisms, which is an example of definition by genus and differentia...

 of therizinosaur
Therizinosaur
Therizinosaurs are theropod dinosaurs belonging to the clade Therizinosauria. Therizinosaur fossils have been found in Early through Late Cretaceous deposits in Mongolia, the People's Republic of China and Western North America...

ian theropod dinosaur
Dinosaur
Dinosaurs are a diverse group of animals of the clade and superorder Dinosauria. They were the dominant terrestrial vertebrates for over 160 million years, from the late Triassic period until the end of the Cretaceous , when the Cretaceous–Paleogene extinction event led to the extinction of...

 from the Cretaceous
Cretaceous
The Cretaceous , derived from the Latin "creta" , usually abbreviated K for its German translation Kreide , is a geologic period and system from circa to million years ago. In the geologic timescale, the Cretaceous follows the Jurassic period and is followed by the Paleogene period of the...

 of China
People's Republic of China
China , officially the People's Republic of China , is the most populous country in the world, with over 1.3 billion citizens. Located in East Asia, the country covers approximately 9.6 million square kilometres...

.

Two species have been named in the genus: the type species
Type species
In biological nomenclature, a type species is both a concept and a practical system which is used in the classification and nomenclature of animals and plants. The value of a "type species" lies in the fact that it makes clear what is meant by a particular genus name. A type species is the species...

 Nanshiungosaurus brevispinus and Nanshiungosaurus bohlini.

Discovery and naming

In 1979 Nanshiungosaurus brevispinus was named and described by Dong Zhiming
Dong Zhiming
Dong Zhiming , from the Institute of Vertebrate Paleontology and Paleoanthropology in Beijing, is one of China's leading paleontologists. He began working at the IVPP in 1962, learning from Yang Zhongjian who was director at the time...

. The generic name refers to Nanxiong
Nanxiong
Nanxiong is a city district of Guangdong Province, China. It is under the administration of Shaoguan city....

. The specific name is derived from Latin
Latin
Latin is an Italic language originally spoken in Latium and Ancient Rome. It, along with most European languages, is a descendant of the ancient Proto-Indo-European language. Although it is considered a dead language, a number of scholars and members of the Christian clergy speak it fluently, and...

 brevis, "short", and spina, "thorn", in reference to the short vertebral spines.

The holotype
Holotype
A holotype is a single physical example of an organism, known to have been used when the species was formally described. It is either the single such physical example or one of several such, but explicitly designated as the holotype...

 specimen, IVPP V4731, was near Dapingcun in Guangdong
Guangdong
Guangdong is a province on the South China Sea coast of the People's Republic of China. The province was previously often written with the alternative English name Kwangtung Province...

 found in a layer of the Yuanpu Formation
Yuanpu Formation
The Yuanpu Formation is a geological formation in Guangdong, China whose strata date back to the Late Cretaceous. Dinosaur remains are among the fossils that have been recovered from the formation.-Vertebrate paleofauna:* Tarbosaurus bataar...

, dating from the Late Cretaceous
Late Cretaceous
The Late Cretaceous is the younger of two epochs into which the Cretaceous period is divided in the geologic timescale. Rock strata from this epoch form the Upper Cretaceous series...

 Campanian
Campanian
The Campanian is, in the ICS' geologic timescale, the fifth of six ages of the Late Cretaceous epoch . The Campanian spans the time from 83.5 ± 0.7 Ma to 70.6 ± 0.6 Ma ...

. It consists of a partial skeleton lacking the skull but including eleven cervical, ten dorsal and six sacral vertebrae, and a bulky pelvis. It was first thought to be a small, strange sauropod characterised by a shorter but thicker neck than other sauropods.

In 1997 Dong and You Hailu named and described a second species: Nanshiungosaurus bohlini, based on a skeleton found in 1992 near Mazongshan. The specific name honours the Swedish paleontologist Birger Bohlin
Birger Bohlin
Dr. Anders Birger Bohlin was a Swedish palaeontologist. As well as his work on dinosaurs and prehistoric mammals, Bohlin was part of the group that established the existence of Peking Man ...

. The holotype is IVPP V 11116, from the Early Cretaceous
Early Cretaceous
The Early Cretaceous or the Lower Cretaceous , is the earlier or lower of the two major divisions of the Cretaceous...

 Upper Xinminbao Group
Xinminbao Group
The Xinminbao Group is a group of geological formations in north central China. They occur across a large depression between the Altai mountains of Mongolia to the north and the Qilian mountains of the Qinghai Plateau to the south, in the Gonpoquan and Suanjingze basins, and also in the...

 dating from the Barremian
Barremian
The Barremian is an age in the geologic timescale between 130.0 ± 1.5 Ma and 125.0 ± 1.0 Ma). It is a subdivision of the Early Cretaceous epoch...

-Aptian
Aptian
The Aptian is an age in the geologic timescale or a stage in the stratigraphic column. It is a subdivision of the Early or Lower Cretaceous epoch or series and encompasses the time from 125.0 ± 1.0 Ma to 112.0 ± 1.0 Ma , approximately...

. It consists of only eleven cervical and five dorsal vertebrae with some ribs. Dong and You presented no evidence or argumentation supporting the assignment of the species to Nanshiungosaurus. In view of the lack of synapomorphies, shared unique traits, and the large age difference with Nanshiungosaurus brevispinus it is generally considered that the second species might warrant its own genus.

Description

Gregory S. Paul
Gregory S. Paul
Gregory Scott Paul is a freelance researcher, author and illustrator who works in paleontology, and more recently has examined sociology and theology. He is best known for his work and research on theropod dinosaurs and his detailed illustrations, both live and skeletal...

 in 2010 estimated the length of Nanshiungosaurus brevispinus at five metres, the weight at six hundred kilogrammes. The species distinguishes itself by the possession of twelve cervical vertebrae. The number of sacral vertebrae was first determined at five, later corrected to six.

"Nanshiungosaurus" bohlini is a larger form, estimated by Paul at six metres and 1.3 tonnes.

Phylogeny

Nanshiungosaurus brevispinus was in 1979 by Dong assigned to the Titanosaurinae, still based on the assumption it were a sauropod. In 1992 the species was assigned to the Segnosauridae, the group today called Therizinosauridae
Therizinosauridae
Therizinosauridae is a family of advanced herbivorous or omnivorous theropod dinosaurs. Therizinosaurid fossil remains have been recovered from mid-late Cretaceous Period deposits from Mongolia, China, and the United States.-Classification:...

. In 1997 however, Dong placed both species in a separate Nanshungosauridae. Cladistic analyses indicate a position for Nanshiungosaurus brevispinus that is either basal in the Therizinosauridae or just outside of that clade, basal in the Therizinosauroidea. Under the definition of Therizinosauridae sensu Xu
Xu Xing
Xu Xing is a famed Chinese paleontologist who has named many dinosaurs, including the Jurassic ceratopsian Yinlong, the Jurassic tyrannosauroid Guanlong, the large oviraptorosaur Gigantoraptor, and the troodontid Mei. He was born in Xinjiang, China, in 1969...

2002, Nanshuingosaurus is by definition a therizinosaurid.

External links

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