The imagery on this page is the basis for a paper entitled A New Dromaeosaurid Theropod from Ukhaa Tolgod (Ömnögov, Mongolia), by M.A. Norell, J.M. Clark, A.H. Turner, P.J. Makovicky, R. Barsbold, and T. Rowe, 2006 (American Museum Novitates 3545:1-51). The abstract is as follows:
We describe a new dromaeosaurid theropod from the Upper Cretaceous Djadokhta Formation of Ukhaa Tolgod, Mongolia. The new taxon, Tsaagan mangas, consists of a well-preserved skull and cervical series. This specimen marks only the second dromaeosaurid taxon from a formation that has otherwise yielded numerous specimens of Velociraptor mongoliensis, and Tsaagan mangas is the only dromaeosaurid known from Ukhaa Tolgod beyond sporadic occurrences of isolated teeth. Tsaagan mangas differs from other dromaeosaurids in the possession of a straight,
untwisted, and pendulous paroccipital process, a large and anteriorly located maxillary fenestra, and a jugal–squamosal contact that excludes the postorbital from the margin of the infratemporal fenestra. The phylogenetic affinities of Tsaagan mangas are determined through a comprehensive phylogenetic analysis of Coelurosauria, confirming its position within Dromaeosauridae. This new specimen, coupled with CT imaging, provides new information on the skull and braincase anatomy
About the Species
This specimen, the holotype and only known specimen, was collected from the Djadokhta Formation (Campanian) of Ukhaa Tolgod, Ömnögov Aimag, Mongolia. It was made available to The University of Texas High-Resolution X-ray CT Facility for scanning by Dr. Mark Norell of the American Museum of Natural History. Funding for scanning was provided by Dr. Norell. Funding for image processing was provided by the High-Resolution X-ray CT Facility.
About this Specimen
The specimen was scanned by Richard Ketcham on 1 May 1998 at the High-Resolution X-ray CT Facility at The University of Texas at Austin. It was scanned along the sagittal axis for a total of 116 slices. Each 512X512 pixel slice is 0.5 mm thick, with an interslice spacing of 0.475 mm and a field of reconstruction of 240 mm.