Velociraptor mongoliensis, Osborn, 1924

Brownstein, Chase Doran, 2021, Dromaeosaurid crania demonstrate the progressive loss of facial pneumaticity in coelurosaurian dinosaurs, Zoological Journal of the Linnean Society 191 (1), pp. 87-112 : 95

Velociraptor mongoliensis

In contrast to Deinonychus antirrhopus , the jugal of Velociraptor mongoliensis is an apparently pneumatized

bone ( Fig. 4B ), with the jugal foramen appearing as a

large, ovoid structure within the antorbital fossa that is adjacent to the articulation between the maxilla and jugal ( Fig. 4B ). Several other large pneumatic foramina are also present close to the anterior end of the jugal. In theropods with a jugal foramen, the jugal sinus extends from this anteriorly placed pneumatic feature towards the posterior end of the jugal (e.g. Brusatte et al., 2012; Gold et al., 2013). In Velociraptor mongoliensis , several smaller, deepened, circular foramina are present on the main surface of the jugal and form a line with the jugal foramen and associated anterior jugal pneumatic features ( Fig. 4B ). However, these may be neurovascular in origin given their size. A large foramen placed at the posterior end of the jugal is also in line with these other pneumatic features.

Figures

Figure 4. Reconstruction of the antorbital sinus in coelurosaurs. The second sentence in the figure caption should read: Skulls of (A) Velociraptor, (B) Tsaagan, (C) Tyrannosaurus, (D) Deinonychus, (E) Saurornithoides, and (F) Khaan. Antorbital sinus in blue, with location of the maxillary fenestra in black and promaxillary fenestra in yellow. Photo of Deinonychus courtesy of the Division of Vertebrate Paleontology, Peabody Museum of Natural History.