living fossil

American  

noun

1. an organism that is a living example of an otherwise extinct group and that has remained virtually unchanged in structure and function over a long period of time, as the coelacanth and the horseshoe crab.

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living fossil British  

noun

1. an animal or plant, such as the coelacanth and ginkgo, belonging to a group most of whose members are extinct

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Etymology

Origin of living fossil

First recorded in 1920–25

Example Sentences

"This specimen not only provides important information about the ancestral skull of all lepidosaurs but also builds on the growing knowledge that the tuatara, while often called a "living fossil"; belongs to a once-diverse order of ancient reptiles with a rich evolutionary history."

From Science Daily

The coelacanth is often called a "living fossil," once believed to have vanished millions of years ago before a live specimen was unexpectedly caught in the Indian Ocean in 1938.

From Science Daily

A living fossil is a term for a species that was once known only from its fossil record and was later discovered in living form, apparently preserving the physical features from long-gone ancestors.

From Los Angeles Times

The Ginkgo Biloba in Leiden, Netherlands, is a 240 year-old "living fossil" and the second oldest in Europe.

From BBC

A living fossil had been found, and botanists were excited.

From Seattle Times