Variraptor
Encyclopedia
Variraptor 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 coelurosaurian
Coelurosauria
Coelurosauria is the clade containing all theropod dinosaurs more closely related to birds than to carnosaurs. In the past, it was used to refer to all small theropods, although this classification has been abolished...

 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 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...

 of France
France
The French Republic , The French Republic , The French Republic , (commonly known as France , is a unitary semi-presidential republic in Western Europe with several overseas territories and islands located on other continents and in the Indian, Pacific, and Atlantic oceans. Metropolitan France...

.

Between 1992 and 1995 amateur paleontologists Patrick Méchin and Annie Méchin-Salessy uncovered the remains of a small theropod in the Grès à Reptiles Formation (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 ...

-Maastrichtian
Maastrichtian
The Maastrichtian is, in the ICS' geologic timescale, the latest age or upper stage of the Late Cretaceous epoch or Upper Cretaceous series, the Cretaceous period or system, and of the Mesozoic era or erathem. It spanned from 70.6 ± 0.6 Ma to 65.5 ± 0.3 Ma...

) at La Bastide Neuve, near Fox-Amphoux
Fox-Amphoux
Fox-Amphoux is a commune in the Var department in the Provence-Alpes-Côte d'Azur region in southeastern France.-References:*...

. The first finds were in 1992 assigned to the dubious theropod genus Elopteryx
Elopteryx
Elopteryx is a genus of troodontid maniraptoran theropod dinosaur based on fragmentary fossils found in late Cretaceous Period rocks of Romania. These fossils date from the early-mid Maastrichtian faunal stage, c.71-68 million years ago...

. A second article, in 1997, concluded they represented a new species. In 1998 this was named by Jean Le Loeuff and Eric Buffetaut as 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...

 Variraptor mechinorum. The generic 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...

 Varus, referring to the Var River
Var River
The Var is a river located in the southeast of France. The name Var originates from the Ligurian word for waterway.The Var flows through the Alpes-Maritimes département for most of its length, with a short stretch in the Alpes-de-Haute-Provence département...

 in the Alpes-Maritimes
Alpes-Maritimes
Alpes-Maritimes is a department in the extreme southeast corner of France.- History : was created by Octavian as a Roman military district in 14 BC, and became a full Roman province in the middle of the 1st century with its capital first at Cemenelum and subsequently at Embrun...

 department in the Provence region
Provence
Provence ; Provençal: Provença in classical norm or Prouvènço in Mistralian norm) is a region of south eastern France on the Mediterranean adjacent to Italy. It is part of the administrative région of Provence-Alpes-Côte d'Azur...

 of southern France, and raptor meaning "thief". The specific name honours the Méchin couple.

The genus is based on three type specimens: a posterior dorsal vertebra (MDE-D168), a sacrum
Sacrum
In vertebrate anatomy the sacrum is a large, triangular bone at the base of the spine and at the upper and back part of the pelvic cavity, where it is inserted like a wedge between the two hip bones. Its upper part connects with the last lumbar vertebra, and bottom part with the coccyx...

 (MDE-D169) with five fused vertebrae, and an ilium
Ilium (bone)
The ilium is the uppermost and largest bone of the pelvis, and appears in most vertebrates including mammals and birds, but not bony fish. All reptiles have an ilium except snakes, although some snake species have a tiny bone which is considered to be an ilium.The name comes from the Latin ,...

 (CM-645). The specimens are part of the collection of the Musée des Dinosaures d'Espéraza and the private Collection Méchin.

Additional referred material includes a right humerus
Humerus
The humerus is a long bone in the arm or forelimb that runs from the shoulder to the elbow....

 (MDE-D158) with a deltopectoral crest more developed than in any other known theropod, suggesting a strong raptorial function for the forearm. Other attributed bones include a femur
Femur
The femur , or thigh bone, is the most proximal bone of the leg in tetrapod vertebrates capable of walking or jumping, such as most land mammals, birds, many reptiles such as lizards, and amphibians such as frogs. In vertebrates with four legs such as dogs and horses, the femur is found only in...

 and various vertebrae. The incomplete remains have dromaeosaurid
Dromaeosauridae
Dromaeosauridae is a family of bird-like theropod dinosaurs. They were small- to medium-sized feathered carnivores that flourished in the Cretaceous Period. The name Dromaeosauridae means 'running lizards', from Greek dromeus meaning 'runner' and sauros meaning 'lizard'...

 features in the shape of the vertebrae and the humerus, with some resemblances to Deinonychus
Deinonychus
Deinonychus was a genus of carnivorous dromaeosaurid dinosaur. There is one described species, Deinonychus antirrhopus. This 3.4 meter long dinosaur lived during the early Cretaceous Period, about 115–108 million years ago . Fossils have been recovered from the U.S...

. An adult animal may have been slightly smaller than Deinonychus at around two meters (6.5 ft) long. However, the identity of the referred fossils has become uncertain.

Taxonomy and validity

In 2000 Ronan Allain and Philippe Taquet
Philippe Taquet
Philippe Taquet is a French paleontologist who specializes in dinosaur systematics of finds primarily in northern Africa.He is a member of the French Academy of Sciences since November 30, 2004...

 named a second small theropod from the same layers: Pyroraptor
Pyroraptor
Pyroraptor is a genus of dromaeosaurid dinosaur from the late Cretaceous Period of France. It is known from a single specimen. It was found in 1992 in the south of France, in Provence, and is known only from a few bones. It was named Pyroraptor olympius by Allain and Taquet in 2000. The name means...

. They also claimed that Variraptor was a nomen dubium
Nomen dubium
In zoological nomenclature, a nomen dubium is a scientific name that is of unknown or doubtful application...

because the type lacked any single diagnostic trait.

In 2009 Buffetaut and Phomphen Chanthasit defended the validity of Variraptor, arguing the type had a unique combination of traits. The lack of overlapping parts would make it impossible to establish whether Pyroraptor was a junior subjective synonym but the presence of two different types of ulna
Ulna
The ulna is one of the two long bones in the forearm, the other being the radius. It is prismatic in form and runs parallel to the radius, which is shorter and smaller. In anatomical position The ulna is one of the two long bones in the forearm, the other being the radius. It is prismatic in form...

 in the southern French dromaeosaurid material would indicate two separate species.

Le Loeuff and Buffetaut described Variraptor as a maniraptora
Maniraptora
Maniraptora is a clade of coelurosaurian dinosaurs which includes the birds and the dinosaurs that were more closely related to them than to Ornithomimus velox. It contains the major subgroups Avialae, Deinonychosauria, Oviraptorosauria and Therizinosauria. Ornitholestes and the Alvarezsauroidea...

n theropod, a member of the Dromaeosauridae
Dromaeosauridae
Dromaeosauridae is a family of bird-like theropod dinosaurs. They were small- to medium-sized feathered carnivores that flourished in the Cretaceous Period. The name Dromaeosauridae means 'running lizards', from Greek dromeus meaning 'runner' and sauros meaning 'lizard'...

, and this has been commonly accepted. However, in 2000 Oliver Rauhut was doubtful, assigning it to the more inclusive Coelurosauria
Coelurosauria
Coelurosauria is the clade containing all theropod dinosaurs more closely related to birds than to carnosaurs. In the past, it was used to refer to all small theropods, although this classification has been abolished...

.
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