keyhole limpet

mollusk

Also known as: Fissurellidae

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Last updated

June 30, 2026

Quick Summary

Keyhole limpets are a type of limpet belonging to the genus Fissurella. Limpets, in general, are snails with flattened shells, and most marine varieties attach themselves to rocks near the coast.12

Keyhole limpets are distinguished by a unique perforation, or hole, at the apex of their shell. This hole serves as an exit for water currents and waste products. They are part of the prosobranch family Fissurellidae.2

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gastropod
Classification
…Japan, Australia, and South Africa; keyhole limpets (Fissurellidae) in intertidal rocky areas. Superfamily Patellacea (Docoglossa) Conical-shelled limpets, without slits or holes, found in rocky shallow waters (Acmaeidae and Patellidae). Superfamily Trochacea
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…Japan, Australia, and South Africa; keyhole limpets (Fissurellidae) in intertidal rocky areas. Superfamily Patellacea (Docoglossa) Conical-shelled limpets, without slits or holes, found in rocky shallow waters (Acmaeidae and Patellidae). Superfamily Trochacea
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limpet
Keyhole limpets, of the prosobranch family Fissurellidae, have a slit or hole at the apex of the shell, through which water currents (and wastes) exit.
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Keyhole limpets, of the prosobranch family Fissurellidae, have a slit or hole at the apex of the shell, through which water currents (and wastes) exit.
Read More