''Sinraptor'' () is a

genus Genus (; : genera ) is a taxonomic rank above species and below family (taxonomy), family as used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In bino ...

of metriacanthosaurid

theropod Theropoda (; from ancient Greek , (''therion'') "wild beast"; , (''pous, podos'') "foot"">wiktionary:ποδός"> (''pous, podos'') "foot" is one of the three major groups (clades) of dinosaurs, alongside Ornithischia and Sauropodom ...

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

from the Late

Jurassic The Jurassic ( ) is a Geological period, geologic period and System (stratigraphy), stratigraphic system that spanned from the end of the Triassic Period million years ago (Mya) to the beginning of the Cretaceous Period, approximately 143.1 Mya. ...

. The name ''Sinraptor'' comes from the

Latin Latin ( or ) is a classical language belonging to the Italic languages, Italic branch of the Indo-European languages. Latin was originally spoken by the Latins (Italic tribe), Latins in Latium (now known as Lazio), the lower Tiber area aroun ...

prefix "Sino", meaning Chinese, and "raptor", meaning robber. The specific name ''dongi'' honours

Dong Zhiming Dong Zhiming (Chinese language, Chinese: 董枝明, Pinyin: ''Dǒng Zhimíng''; January 1937 – 20 October 2024) was a Chinese vertebrate paleontologist formerly employed at the Institute of Vertebrate Paleontology and Paleoanthropology (IVPP) ...

. Despite its name, ''Sinraptor'' is not related to

dromaeosaurid Dromaeosauridae () is a family (biology), family of feathered coelurosaurian Theropoda, theropod dinosaurs. They were generally small to medium-sized feathered carnivores that flourished in the Cretaceous period (geology), Period. The name Drom ...

s (often nicknamed "raptors") like ''

Velociraptor ''Velociraptor'' (; ) is a genus of small dromaeosaurid dinosaurs that lived in Asia during the Late Cretaceous epoch, about 75 million to 71 million years ago. Two species are currently recognized, although others have been assigned in th ...

''. Instead, it was a carnosaur distantly related to ''

Allosaurus ''Allosaurus'' ( ) is an extinct genus of theropod dinosaur that lived 155 to 145 million years ago during the Late Jurassic period ( Kimmeridgian to late Tithonian ages). The first fossil remains that could definitively be ascribed to th ...

''. ''Sinraptor'' and its close relatives were among the earliest members of the Jurassic carnosaurian radiation. ''Sinraptor'' still remains the best-known member of the

family Family (from ) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). It forms the basis for social order. Ideally, families offer predictabili ...

Metriacanthosauridae, with some older sources even using the name "Sinraptoridae" for the family.

Discovery

Zigong Dinosaur Museum Yangchuanosaurus hepingensis

The

holotype A holotype (Latin: ''holotypus'') is a single physical example (or illustration) of an organism used when the species (or lower-ranked taxon) was formally described. It is either the single such physical example (or illustration) or one of s ...

specimen of ''Sinraptor'' was uncovered from the Shishugou Formation during a joint Chinese/Canadian expedition to the northwestern Chinese desert in 1987 and described by Philip J. Currie and Zhao Xijin in 1994. Standing nearly tall and measuring roughly in length, two species of ''Sinraptor'' have been named. ''S. dongi'', the

type species In International_Code_of_Zoological_Nomenclature, 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 spe ...

, was described by Currie and Zhao in 1994. A second species, originally named '' Yangchuanosaurus hepingensis'' by Gao in 1992, may actually represent a second species of ''Sinraptor''. Whether or not this is the case, ''Sinraptor'' and ''Yangchuanosaurus'' were close relatives and are classified together in the family

Metriacanthosauridae Metriacanthosauridae (Greek for "moderately-spined lizards") is an extinct family of allosauroid theropod dinosaurs that lived in Europe and Asia from the Middle Jurassic to the Early Cretaceous. The family is split into two subgroups: Metriacan ...

. Gregory S. Paul proposed that ''S. dongi'' would reach in length and in body mass, while Holtz estimated it to be in length. The dentition of ''Sinraptor'' was very similar to that of ''Allosaurus'' and indicated that it likely would have preyed upon medium-sized dinosaurs such as stegosaurs by using its blade-like teeth to inflict massive, fatal wounds. ''Sinraptor hepingensis'', formerly referred to as '' Yangchuanosaurus'', is a second species referred to this genus. However, the identity of this species within ''Sinraptor'' is questioned by other paleontologists, and the describers of '' Alpkarakush'' included this species within '' Yangchuanosaurus'' based on their phylogenetic analysis in 2024.

Paleopathology

''Sinraptor dongi'' skull specimen IVPP 10600 exhibits "a variety of gently curving tooth drags or gouges, shallow, circular punctures and one fully penetrating

lesion A lesion is any damage or abnormal change in the tissue of an organism, usually caused by injury or diseases. The term ''Lesion'' is derived from the Latin meaning "injury". Lesions may occur in both plants and animals. Types There is no de ...

." One rib was broken and healed via telescoping of its capitular shaft.Molnar, R. E., 2001, Theropod paleopathology: a literature survey: In: Mesozoic Vertebrate Life, edited by Tanke, D. H., and Carpenter, K., Indiana University Press, p. 337-363.

References

External links

The original Chinese text of Gao (1992)'s description of ''Yangchuanosaurus hepingensis'', with pictures.
{{Taxonbar, from=Q311284 Metriacanthosauridae Dinosaur genera Oxfordian dinosaurs Shishugou Formation Taxa named by Philip J. Currie Taxa named by Zhao Xijin Fossil taxa described in 1994 Dinosaurs of China