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Describer
Osborn, 1924 Time
Cretaceous Late ?Santonian Campanian Classification Saurischia Theropoda Tetanurae Coelurosauria Dromaeosauridae
Diet Carnivore Fossilsite
Djadochta Formation, Beds of Toogreeg, (Tögrög) Omnogov, Bayan Dzag, Mongolia; Minhe Formation Nei Mongol Zizhiqu, China Length 1,8 meter Info Genus - Typespecies - Skull Velociraptor mongoliensis (Osborn, 1924) > Ovoraptor djadochtari (Osborn, 1924) > Velociraptor osmolskae (Godefroit, Currie, Li, Shang, and Dong 2008)
More than 6 partial to complete skulls and skeletons.
V.mongoliensis is well known from at least half a dozen fragmentary to complete specimens from Upper Cretaceous strata, the Djadochta Formation and possibly the Barun Goyot Formation of Mongolia. This is the best known example of the family after Deinonychus antirrhopus but not as yet completely described. Velociraptor had a low skull, atail stiffened by rod like extensions of the prezygapophyses and hemal arches, a simulinate (pully-like) carpal, an opisthopubic pelvis, and a functionally didactylous foot in which the second pedal digit was raised above the ground to support the strongly enlarged ungual phalanx. It was one of the first to show evidence of the connections between dinosaur faunas of Central Asia and North America. One specimen is well known as part of the "figthing dinosaurs"discovery, in which predators sharp claws were found thrust into the tissues of the head and abdomen of a Protoceratops. The well preserved material of the Late Cretaceous dromaeosaurid, Velociraptor mongoliensis, has allowed us to supplement earlier descriptions of the skull in this species. The skull of V. mongoliensis is similar to that of Deinonychus antirrhopus, but differs from the latter by: (1) laterally convex supratemporal arcade resulting in short, rounded supratemporal fenestra; (2) depressed nasal; (3) longer maxillary process of premaxilla; (4) lack of separate prefrontal, and (5) convex ventral border of the dentary. These differences, especially that in the structure of the temporal region, support generic distinction of Deinonychus antirrhopus and Velociraptor. Skulls of other dromaeosaurids are compared. Barsbold, R. & Osmólska, H. (1999). The skull of Velociraptor (Theropoda) from the Late Cretaceous of Mongolia. Acta Palaeontologica Polonica 44, 2, 189-219. Velociraptor is based on a skull and partial skeleton from Bayan Dzag. An complete skeleton associated with a skeleton of Protoceratops was found in the Beds of Toogreeg. Other specimens of Velociraptor have been reported from the Barun Goyot Formation at Khulsan (Osmolska, 1980, 1982; Norell and Clark, 1992), and the Syuksyukskaya Svita of Kazakhstan (Nessov, 1995), although it hes not yet be determined whether or not they represent the same species. Barsbold 1983 Holotype. AMNH 6515; partially destroyed skull and manual phalanges. Description . Low skull with elongated facial region. Maxillary fenestrae small and spherical. Basipterygoid processes directed anteroventrally. Mobile basipterygoid articulation. Osseous middle ear cavity absent. Lateral walls of the cranium composed of the prootic and laterosphenoid, forming a mobile articulation with the parietal. An elongate furrow diverges from the foramen ovale, limiting the upper posterior part of the middle ear cavity and supposedly containing the stapes. A foramen for the facial nerve is found anteroventral to the foramen ovale. The coronoid bone forms a mobile, groove-like articulation with the articulation of the anterior and posterior jaw ramus. The teeth are relatively large, with large spaces between them, and anterior and posterior serrations. Slender postcranial skeleton. Ten cervicals, 13 dorsals, and five fused sacral vertebrae. With the exception of those most anterior, caudal prezygapophyses and chevrons have elongated ossified tendons, which are the ossified tendons of the caudal musculature. This ossified [sheath] stretches for a length of 8 to 10 vertebrae, and follows a compactly packed course placed symmetrically along the transverse processes. The sternum is flattened, large, and shaped like a shield. Narrow grooves for the articulation of the coracoids are developed on the dorsolateral edges of the sternum. Clavicles absent. Abdominal ribs consist of narrow lateral and medial segments. Scapulocoracoids with a spherical, widened coracoid part and a narrow, elongated scapular blade. Low, elongated ilium with an anterior process that is divided in two, and a thickened posteroventral edge. The pubis is elongated anteriorly, oriented posteroventrally, and has a laterally compressed distal end. Ischium shortened, parallel to the pubis, and has a large obturator process. Forelimbs not reduced, and humerus with a large deltoid crest. Carpus with a pulley construction, manus of "grasping" type. Metatarsal III is thinned along the shaft, and shorter than II and IV. Pedal digit II is of the reversed type, and bears a large "predatory" ungual phalanx. Discussion. The low skull, widely spaced teeth, and slender postcranial skeleton distinguish Velociraptor from the dromaeosaurids and Deinonychus antirrhopus.
Material. Complete skeleton with skull of one specimen (no. 100/25), and partially destroyed skull and remains of postcranial skeleton of another (no. 100/24). Source: Polyglot Paleontologist
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