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Incisivosaurus gauthieriFossil, Oviraptorid
Dr. Amy Balanoff - Columbia University
Dr. Xing Xu, Dr. Yoshimura Kobayashi, Dr. Yusuke Matsufune, and Dr. Mark A. Norell
Incisivosaurus gauthieri
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Chinese Academy of Sciences (IVPP 13326) - holotype

Image processing: Dr. Amy Balanoff
Publication Date: 15 Jul 2009


The imagery on this page is the basis for a paper entitled Cranial osteology of the theropod dinosaur Incisivosaurus gauthieri (Theropoda: Oviraptorosauria), by A.M. Balanoff, X. Xu, Y. Kobayashi, Y. Matsufune, and M.A. Norell, 2009 (American Museum Novitates 3651:1-35). The abstract is as follows:

       We provide a description of the holotype skull of the unusual oviraptorosaur Incisivosaurus gauthieri.        Previous phylogenetic analyses have placed this taxon firmly within Oviraptorosauria near the base of        the clade; however, until now only a cursory description of this important specimen was available.        The presence of many primitive characteristics (e.g., maxillary and dentary teeth as well as an        extended palate and rostrum) indicates that the observed similarities between avians and derived        oviraptorids are convergences rather than shared derived characters. In addition, we clarify previous        descriptions of several ambiguous anatomical features, most notably of the palate. We also employ a        computed tomographic (CT) analysis, which allows for a more complete description of the braincase        and the reconstruction of an endocranial endocast. CT imagery reveals features that were before        unobtainable, such as the presence of a replacement tooth behind the large rodentiform incisor in        the premaxilla. This arrangement indicates that although the incisiform teeth of I. gauthieri are        morphologically distinct they are replaced in typical archosaurian fashion.

About the Species

This specimen, the holotype and only known specimen, was discovered in the Early Cretaceous rocks of northeastern China. It was collected from the lower part of the Yixian Formation.

About this Specimen

The specimen was scanned at Stony Brook University medical scanning facility. It was scanned along the coronal axis for a total of 404 slices, and each 512X512 pixel slice is 0.310 mm thick.

About the


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& Links
Skull with endocast roll movie

Click on the thumbnail to the left for a roll animation (2.6 mb) of the Incisivosaurus cranial endocast highlighted in blue within the skull, which is rendered semi-transparent.

endocast roll movie

Click on the thumbnail to the left for a roll animation (1.7 mb) of the isolated Incisivosaurus cranial endocast.

Skull with endocast yaw movie

Click on the thumbnail to the left for a yaw animation (2.3 mb) of the Incisivosaurus cranial endocast highlighted in blue within the skull, which is rendered semi-transparent.

endocast yaw movie

Click on the thumbnail to the left for a yaw animation (2.8 mb) of the isolated Incisivosaurus cranial endocast.

Skull with endocast pitch movie

Click on the thumbnail to the left for a pitch animation (1.5 mb) of the Incisivosaurus cranial endocast highlighted in blue within the skull, which is rendered semi-transparent.

endocast pitch movie

Click on the thumbnail to the left for a pitch animation (1.7 mb) of the isolated Incisivosaurus cranial endocast.


To cite this page: Dr. Amy Balanoff, Dr. Xing Xu, Dr. Yoshimura Kobayashi, Dr. Yusuke Matsufune, and Dr. Mark A. Norell, 2009, "Incisivosaurus gauthieri" (On-line), Digital Morphology. Accessed October 21, 2014 at http://digimorph.org/specimens/Incisivosaurus_gauthieri/.

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