The imagery on this page is the basis for a paper entitled The Skull of the Round Island Boa, Casarea dussumieri Schlegel, Based on High-Resolution X-ray Computed Tomography, by J.A. Maisano and O. Rieppel (2007, Journal of Morphology 268:371-384). The abstract is as follows:

       The skull of the rare bolyeriid snake Casarea dussumieri is described in detail based on high-        resolution X-ray CT data. Bolyeriids are unique in their possession of a separate suborbital ossification        and a maxilla subdivided into two movably jointed parts, which may be the result of paedomorphic        truncation of the development of the maxilla from multiple ossification centers. Comparison of the        skull of C. dussumieri to that of larger booids suggests additional paedomorphic features including        reduction of the dorsal lamina of the nasal and prefrontal and reduction of their contacts with the        frontal, limited posterior extent of the posterior free process of the supratemporal, and reduction of        the coronoid and splenial. The observations herein do not resolve competing phylogenetic        hypotheses based on morphology, which either place tropidophiids as the sister-taxon of bolyeriids,        Acrochordus and colubroids, or place bolyeriids as the sister-taxon of the other three. But these        observations provide no support whatsoever for the heterodox placement of tropidophiids at the        base of alethinophidian snakes, as obtained recently with molecular data.

This specimen was collected from Round Island, Mauritius. It was made available to The University of Texas High-Resolution X-ray CT Facility for scanning by Dr. Jessie Maisano of The University of Texas at Austin and Mr. Greg Schneider of the University of Michigan Museum of Zoology. Funding for scanning and image processing was provided by a National Science Foundation Assembling the Tree of Life grant (EF-0334961), The Deep Scaly Project: Resolving Squamate Phylogeny using Genomic and Morphological Approaches, to Drs. Jacques Gauthier of Yale University, Maureen Kearney of the Field Museum, Jessie Maisano of The University of Texas at Austin, Tod Reeder of San Diego State University, Olivier Rieppel of the Field Museum, Jack Sites of Brigham Young University, and John Wiens of SUNY Stonybrook.

Dorsal view of the scanned specimen.

The specimen was scanned by Matthew Colbert on 8 June 2005 along the coronal axis for a total of 1004 slices. Each 1024x1024 pixel slice is 0.018 mm thick, with an interslice spacing of 0.018 mm and a field of reconstruction of 8.5 mm.

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Links

Casarea dussumieri page on EncylopÆdia Mauritiana

Three-dimensional volumetric renderings of the skull with the jaw removed, and of the isolated left mandible. All are less than 2mb.

Skull pitch movie	Skull roll movie
Mandible yaw movie	Mandible pitch movie	Mandible roll movie

Front page image.