The imagery on this page is the basis for a paper entitled Cranial Osteology of the African Gerrhosaurid Angolosaurus skoogi (Squamata; Gerrhosauridae), by H. A. Nance (2007, African Journal of Herpetology 56:39-75). The abstract is as follows:

       Phylogenetic relationships both within and between the scincomorph families Gerrhosauridae and        Cordylidae are in need of re-examination. Currently the basal gerrhosaurid is unknown, although        Angolosaurus skoogi previously was proposed as the sister taxon to mainland African gerrhosaurids.        Many details of the cranial osteology of A. skoogi are also unknown because of the rarity in museum        collections and elusive lifestyle of this dune-dwelling lizard, endemic to the Namib Desert. In this        study, High-Resolution X-ray Computed Tomography (HRXCT) was used to study in detail the cranial        osteology of A. skoogi. Results of this study enabled completion of the first anatomical description of        the skull and mandible of A. skoogi. Throughout the description, reference is made to a fully labeled        cross-sectional HRXCT data set, available online as supplementary material. Detailed information on        cranial osteology obtained from these data can help resolve the contentious placement of A. skoogi        within Gerrhosauridae. Unlike other Cordyliformes (Gerrhosauridae + Cordylidae), the postfrontal in A.        skoogi is not extensive and does not extend posteriorly beyond the orbital margin. The squamosal is        not bifurcated anteriorly in A. skoogi, unlike other gerrhosaurids. In the braincase of A. skoogi, there        is no separate foramen for passage of the glossopharyngeal nerve (cranial nerve IX). This        morphological study emphasizes the utility of both HRXCT scans and disarticulated skeletal material as        valuable sources of phylogenetically-informative data.

This specimen was collected near the Ondonduiergo River, Opuwo District, Kunene Region, Namibia by A.M. Bauer, A.C. Lamb, W.R. Branch and J.L. Wright on 27 July 1998. It was made available to The University of Texas High-Resolution X-ray CT Facility for scanning by Dr. Chris Bell of The University of Texas at Austin. Funding for scanning was provided by Dr. Bell. Funding for image processing was provided by a NSF Digital Libraries Initiative grant to Dr. Timothy Rowe of The University of Texas at Austin.

This specimen was scanned by Richard Ketcham on 28 March 2000 along the coronal axis for a total of 402 slices. Each 512x512 pixel slice is 0.053 mm thick, with an interslice spacing of 0.053 mm and a field of reconstruction of 18 mm.

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Links

Gerrhosauridae page on The Reptile Database

Three-dimensional volumetric renderings of the skull with the osteoderms removed. All are 2mb or less.

Yaw movie	Pitch movie	Roll movie

Front page image.