A snail is a shelled gastropod. The name is most often applied to land snails, terrestrial pulmonate gastropod molluscs. However, the common name snail is also used for most of the members of the molluscan class Gastropoda that have a coiled shell that is large enough for the animal to retract completely into. When the word "snail" is used in this most general sense, it includes not just land snails but also numerous species of sea snails and freshwater snails. Gastropods that naturally lack a shell, or have only an internal shell, are mostly called slugs, and land snails that have only a very small shell are often called semi-slugs.
The gastropods, commonly known as slugs and snails, belong to a large taxonomic class of invertebrates within the phylum Mollusca called Gastropoda.
Heterobranchia, the heterobranchs, is a taxonomic clade of snails and slugs, which includes marine, aquatic and terrestrial gastropod mollusks.
The operculum is a corneous or calcareous anatomical structure like a trapdoor that exists in many groups of sea snails and freshwater snails, and also in a few groups of land snails; the structure is found in some marine and freshwater gastropods, and in a minority of terrestrial gastropods, including the families Helicinidae, Cyclophoridae, Aciculidae, Maizaniidae, Pomatiidae, etc.
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.
Cone snails, or cones, are highly venomous sea snails of the family Conidae.
The Trochidae, common name top-snails or top-shells, are a family of various sized sea snails, marine gastropod molluscs in the subclass Vetigastropoda. This family is commonly known as the top-snails because in many species the shell resembles a toy spinning top.
Notocrater is a genus of deep-water true limpets, marine gastropod molluscs in the family Pseudococculinidae, one of the families of true limpets.
Fasciolariidae is a family of small to large sea snails, marine gastropod mollusks in the superfamily Buccinoidea. Species in Fasciolariidae are commonly known as tulip snails and spindle snails.
Freshwater snails are gastropod mollusks that live in fresh water. There are many different families. They are found throughout the world in various habitats, ranging from ephemeral pools to the largest lakes, and from small seeps and springs to major rivers. The great majority of freshwater gastropods have a shell, with very few exceptions. Some groups of snails that live in freshwater respire using gills, whereas other groups need to reach the surface to breathe air. In addition, some are amphibious and have both gills and a lung. Most feed on algae, but many are detritivores and some are filter feeders.
Turrilatirus melvilli is a species of sea snail, a marine gastropod mollusk in the family Fasciolariidae, the spindle snails, the tulip snails and their allies.
Turrilatirus turritus is a species of sea snail, a marine gastropod mollusk in the family Fasciolariidae, the spindle snails, the tulip snails and their allies.
Turrilatirus iris is a species of sea snail, a marine gastropod mollusk in the family Fasciolariidae, the spindle snails, the tulip snails and their allies.
Latirulus is a genus of sea snails, marine gastropod mollusks in the family Fasciolariidae, the spindle snails, the tulip snails and their allies.
Latirus is a genus of sea snails, marine gastropod molluscs in the family Fasciolariidae, the spindle snails, the tulip snails and their allies.
Boreotrophon is a genus of sea snails, marine gastropod mollusks in the subfamily Pagodulinae of the family Muricidae, the murex snails or rock snails.
In 1758, in the 10th edition of Systema Naturae, the Swedish scientist and taxonomist Carl Linnaeus described the class "Vermes" as:
Animals of slow motion, soft substance, able to increase their bulk and restore parts which have been destroyed, extremely tenacious of life, and the inhabitants of moist places. Many of them are without a distinct head, and most of them without feet. They are principally distinguished by their tentacles. By the Ancients they were not improperly called imperfect animals, as being destitute of ears, nose, head, eyes and legs; and are therefore totally distinct from Insects.
In the shell of gastropod mollusks, the lip is the free margin of the peristome or aperture of the gastropod shell.
Conus is a genus of predatory sea snails, or cone snails, marine gastropod mollusks in the family Conidae. Prior to 2009, cone snail species had all traditionally been grouped into the single genus Conus. However, Conus is now more precisely defined, and there are several other accepted genera of cone snails. For a list of the currently accepted genera, see Conidae.
Terrestrial molluscs or land molluscs (mollusks) are an ecological group that includes all molluscs that live on land in contrast to freshwater and marine molluscs. They probably first occurred in the Carboniferous, arising from freshwater ones.
