Valdoraptor
Encyclopedia
Valdoraptor 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 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 Early 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...

. Its fossils were found in England
England
England is a country that is part of the United Kingdom. It shares land borders with Scotland to the north and Wales to the west; the Irish Sea is to the north west, the Celtic Sea to the south west, with the North Sea to the east and the English Channel to the south separating it from continental...

. It is known only from bones of the feet
Metatarsus
The metatarsus or metatarsal bones are a group of five long bones in the foot located between the tarsal bones of the hind- and mid-foot and the phalanges of the toes. Lacking individual names, the metatarsal bones are numbered from the medial side : the first, second, third, fourth, and fifth...

.

In 1858 Richard Owen
Richard Owen
Sir Richard Owen, FRS KCB was an English biologist, comparative anatomist and palaeontologist.Owen is probably best remembered today for coining the word Dinosauria and for his outspoken opposition to Charles Darwin's theory of evolution by natural selection...

 referred a fossil consisting of a set of three metatarsals, foot bones, part of the collection of the British Museum of Natural History, to the herbivorous dinosaur genus Hylaeosaurus
Hylaeosaurus
Hylaeosaurus is the most obscure of the three animals used by Sir Richard Owen to first define the new group Dinosauria, in 1842. The original specimen, recovered by Gideon Mantell from the Tilgate Forest in the south of England in 1832, now resides in the Natural History Museum of London, where...

because of its size and bone texture. Owen had a lithograph
Lithography
Lithography is a method for printing using a stone or a metal plate with a completely smooth surface...

 made of the bones that gave a mirrored image: although they were in fact from the left foot, it now seemed they were from the right foot.

By 1881 John Whitaker Hulke had recognised that the specimen represented a foot from a carnivorous theropod. In 1888 Richard Lydekker
Richard Lydekker
Richard Lydekker was an English naturalist, geologist and writer of numerous books on natural history.-Biography:...

 referred the specimen to the theropod species Megalosaurus
Megalosaurus
Megalosaurus is a genus of large meat-eating theropod dinosaurs of the Middle Jurassic period of Europe...

 dunkeri
but in 1889 he named a separate species for it because of the more robust build: Megalosaurus oweni. The specific name honours Owen. Lydekker was deceived by the 1858 illustration into thinking that it was the right foot. He also incorrectly assumed it had four metatarsals, a mistake repeated for over a century. Lydekker referred several other foot specimens to the species: BMNH 2574, 2661 and 2680 from the same stratigraphic horizon, and also BMNH R604d and BMNH R1525, uncovered from the earlier Wadhurst Clay Formation in the Hollington Quarry near Hastings
Hastings
Hastings is a town and borough in the county of East Sussex on the south coast of England. The town is located east of the county town of Lewes and south east of London, and has an estimated population of 86,900....

.

In 1923 Friedrich von Huene
Friedrich von Huene
Friedrich von Huene was a German paleontologist who named more dinosaurs in the early 20th century than anyone else in Europe.-Biography:...

 assigned the species to Altispinax
Altispinax
Altispinax is a genus of theropod dinosaur from the Early Cretaceous Obernkirchen Sandstein of Niedersachsen, Germany. Material has also been referred to it from the Hastings Beds , Purbeck Beds , and Lower Greensand of England, and the Weald Clay of England and Belgium, but this material...

, making the combination Altipsinax oweni.

In 1991 George Olshevsky
George Olshevsky
George Olshevsky is a freelance editor, writer, publisher, amateur paleontologist, and mathematician living in San Diego, California.Olshevsky maintains the comprehensive online Dinosaur Genera List...

 placed the species in a new genus, Valdoraptor, renaming its 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...

 Megalosaurus oweni into Valdoraptor oweni. 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...

 Valdus, "Wealden", referring to the Wealden Group
Wealden Group
The Wealden Group is a group in the lithostratigraphy of southern England. The Wealden group consists of paralic to continental facies sedimentary rocks of Valanginian to Barremian age and thus forms part of the English Lower Cretaceous. It is composed of alternating sands and clays...

, and raptor, "plunderer".

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...

, BMNH R2559 (incorrectly given by Owen as BMNH R2556), was found near Cuckfield
Cuckfield
Cuckfield is a large village and civil parish in the Mid Sussex District of West Sussex, England, on the southern slopes of the Weald. It lies south of London, north of Brighton, and east northeast of the county town of Chichester. Nearby towns include Haywards Heath to the southeast and Burgess...

 in layers of the Tunbridge Wells Sand Formation dating from the late Valanginian
Valanginian
In the geologic timescale, the Valanginian is an age or stage of the Early or Lower Cretaceous. It spans between 140.2 ± 3.0 Ma and 136.4 ± 2.0 Ma...

. The specimen is damaged lacking parts of the upper and lower ends. It has a conserved length of 215 millimetres (8.5 in) and an estimated length of 240 millimetres (9.4 in). The species has been suggested to be identical to either Neovenator
Neovenator
Neovenator is a genus of allosauroid dinosaur. Since its discovery on the Isle of Wight, UK, it has become one of the best-known large carnivorous dinosaurs in Europe. Neovenator was at first considered possibly a new species of Megalosaurus. It measured approximately 7.5 meters in length,...

or Eotyrannus
Eotyrannus
Eotyrannus was a genus of tyrannosauroid theropod dinosaur hailing from the Early Cretaceous Wessex Formation beds, included in Wealden Group, located in the southwest coast of the Isle of Wight, United Kingdom...

; it has also been held to be a nomen dubium
Nomen dubium
In zoological nomenclature, a nomen dubium is a scientific name that is of unknown or doubtful application...

. However, Darren Naish
Darren Naish
Darren Naish is a vertebrate palaeontologist and science writer. He obtained a geology degree at the University of Southampton and later studied vertebrate palaeontology under British palaeontologist David Martill at the University of Portsmouth, where he obtained both an M. Phil...

 in 2007 concluded that the specimen showed two unique derived traits or autapomorphies, in that the second metatarsal is both mediolaterally compressed and features a prominent dorsolateral ridge. These traits imply it is a valid taxon and different from Neovenator and Eotyrannus.

Olshevsky assigned Valdoraptor to the Allosauridae but Naish in 2007 stated that no more precise determination was possible than the more general Tetanurae
Tetanurae
Tetanurae, or "stiff tails", is a clade that includes most theropod dinosaurs, as well as birds. Tetanurans first appear during the early or middle Jurassic Period.-Definition:...

.
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