Living fossil

Organism resembling a form long shown in the fossil records

A living fossil is a term for an extant taxon that phenotypically resembles related species known only from the fossil record, though scientifically the term is deprecated and avoided. To be considered a living fossil, the fossil species must be old relative to the time of origin of the extant clade. Living fossils commonly are of species-poor lineages, but they need not be.

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