The bones of the carapace and plastron from which this species has been determined were discovered in a thin seam of grey sand intercalated in the Mammalian band of the Lower Headon Beds at Hordwell, Hampshire. They were lying scattered over an area of about four feet. The broken edge of the entoplastral and right hyoplastral were sticking out of the cliff face. The sea had carried away the missing portions of these bones and probably those lost of the carapace and plastron.