marine snail

mollusk

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Last updated

June 30, 2026

Quick Summary

A marine snail is a type of mollusk belonging to the class Gastropoda. Gastropods are characterized by a soft body, a mantle that secretes a shell, and a muscular foot for locomotion. While many marine snails have a prominent, coiled shell into which they can retract for protection, some species have reduced or absent shells.

These creatures exhibit a vast range of sizes, from less than a millimeter to over two feet in length for some marine species. They inhabit diverse marine environments, from tidal zones to the deep sea. Their diets vary, with some being herbivores, others scavengers, and some carnivorous predators that can even bore through the shells of other mollusks.12

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gastropod
Size range and diversity of structure
Some adult marine snails (Homalogyra) and forest-litter snails (Stenopylis, Punctum) are less than one millimetre (0.04 inch) in diameter. At the other extreme, the largest land snail, the African Achatina achatina, forms a shell that is almost 20 centimetres (eight inches) long. The largest freshwater snails, Pomacea…
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Some adult marine snails (Homalogyra) and forest-litter snails (Stenopylis, Punctum) are less than one millimetre (0.04 inch) in diameter. At the other extreme, the largest land snail, the African Achatina achatina, forms a shell that is almost 20 centimetres (eight inches) long. The largest freshwater snails, Pomacea…
Read More