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Anchura
fossil snail genus
Anchura, genus of extinct marine gastropods (snails) found as fossils only in marine deposits of Cretaceous age (between 145.5 million and 65.5 million years old). It is thus a useful guide or index fossil because it is easily recognizable. The shell whorls are globular and ornamented with raised crenulations; the spire is sharply pointed; the body whorl, the final and largest whorl, has a prominently extended outer lip.
This article was most recently revised and updated by Richard Pallardy.
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