- Project title
- 3D morphology of a Permian xenacanth shark head
- Description of the project
- The early evolution of sharks and their relatives (chondrichthyans : sharks, rays, and chimaeras) is obscured by a very poor fossil record of internal skeletal remains (e.g. the head, jaws, gill arches). Lebach, a Permian locality in Saarland, Germany preserves several early sharks in siderite concretions, often preserving their internal skeletons in three-dimensions. Since their discovery in the early 19th century many of these fossils have become key to our understanding of early chondrichthyans, but many have also destructively prepared during this time, using acid to create moulds. Xenacanth sharks are one of these key chondrichthy an taxa. Now thought to be early stem-group elasmobranchs (sharks and rays) they lie at an important phylogenetic juncture for understanding how modern chondrichthyan groups arose. Several species are known from Lebach, including Triodus, Pleuracanthus, and Xenacanthus. We propose to scan a fossilised head of a Xenacanthus decheni from the MNHN collections, which was never prepared and sopreserves the calcified cartilage comprising the head, jaws, gills, and pharynx. If successful, this will be the first 3D data on a complete xenacanth head, and will be of great importance to understanding the early evolution of chondrichthyans.
Works done by the platform AST-RX
