conodont

conodont

a tooth-like fossil, amber in colour. Conodonts occur in sediments from the CAMBRIAN to the TRIASSIC and are thought to be associated with the mouth-parts of primitive chordates such as members of the AGNATHA.

Collins Dictionary of Biology, 3rd ed. © W. G. Hale, V. A. Saunders, J. P. Margham 2005