Sea snail is a common name for slow-moving marine gastropod molluscs, usually with visible external shells, such as whelk or abalone. They share the taxonomic class Gastropoda with slugs, which are distinguished from snails primarily by the absence of a visible shell.
A species of sea snail in its natural habitat: two individuals of the wentletrap Epidendrium billeeanum with a mass of egg capsules in situ on their food source, a red cup coral.
The shell of Syrinx aruanus can be up to 91 cm long.
A hermit crab occupying a shell of Acanthina punctulata has been disturbed, and has retracted into the shell, using its claws to bar the entrance in the same way the snail used its operculum.
Gastropods, commonly known as slugs and snails, belong to a large taxonomic class of invertebrates within the phylum Mollusca called Gastropoda.
Gastropoda
Cepaea nemoralis: a European pulmonate land snail, which has been introduced to many other countries
The shell of Zonitoides nitidus, a small land snail, has dextral coiling, which is typical (but not universal) of gastropod shells.
The upper pair of tentacles on the head of Helix pomatia have eye spots, but the main sensory organs of the snail are sensory receptors for olfaction, situated in the epithelium of the tentacles.
