Abstract from A New Turtle from the Arundel Clay Facies (Potomac Formation, Early Cretaceous) of Maryland, U.S.A., by T. R. Lipka, F. Therrien, D. B. Weishampel, H. A. Jamniczky, W. G. Joyce, M. W. Colbert and D. B. Brinkman, 2006 (Journal of Vertebrate Paleontology 26:300-307):

       A new paracryptodiran turtle, Arundelemys dardeni, gen. et sp. nov., is described on the basis of an        isolated, nearly complete skull from the Early Cretaceous Arundel Clay facies of Maryland, USA. The        basicranial region exhibits the paracryptodiran condition of a single foramen for the canalis caroticus        internus located midway along the basisphenoid. As revealed by CT scans, the basicranial region of        Arundelemys is unusual in that the right and left canales carotici interni merge just before reaching        the sella turcica and the canalis caroticus lateralis is very small or absent. A phylogenetic analysis        places Arundelemys dardeni as the basal-most member of the Paracryptodira. Within the        Paracryptodira, Arundelemys dardeni is most similar to Compsemys victa in general proportions.

This specimen was collected from the Muirkirk locality of the Early Cretaceous Arundel Clay facies, Potomac Formation. It was made available to the University of Texas High-Resolution X-ray CT Facility for scanning by Dr. Donald Brinkman of the Royal Tyrrell Museum of Palaeontology. Funding for scanning was provided by Dr. Brinkman. Funding for image processing was provided by a National Science Foundation Digital Libraries Initiative grant to Dr. Timothy Rowe of The University of Texas at Austin.

Lateral view of skull	Dorsal view of skull	Ventral view of skull

The specimen was scanned by Matthew Colbert on 16 November 2004 along the coronal axis for a total of 630 slices. Each 1024x1024 pixel slice is 0.095 mm thick, with an interslice spacing of 0.095 mm and a field of reconstruction of 44.5 mm.

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