Conodont

Conodonts Temporal range: Cambrian to Earliest Jurassic (Hettangian) PreꞒ Ꞓ O S D C P T J K Pg N
Conodont elements
Scientific classification
Kingdom:	Animalia
Phylum:	Chordata
Subphylum:	Vertebrata
Class:	†Conodonta Eichenberg, 1930[1]
Groups
Paraconodontida Amphigeisiniformes Westergaardodiniformes Euconodonta Caviodonti Proconodontiformes Conodonti Protopanderodontida Panderodontida Prioniodinida Ozarkodinida
Synonyms
†Conodontophorida (otherwise an order according to Sepkoski, 2002[2])

Conodonts (Greek kōnos, "cone", + odont, "tooth") are an extinct group of agnathan (jawless) vertebrates resembling eels, classified in the class Conodonta. For many years, they were known only from their tooth-like oral elements, which are usually found in isolation and are now called conodont elements. Knowledge about soft tissues remains limited. They existed in the world's oceans for over 300 million years, from the Cambrian to the beginning of the Jurassic. Conodont elements are widely used as index fossils, fossils used to define and identify geological periods. The animals are also called Conodontophora (conodont bearers) to avoid ambiguity.