A snail is, in loose terms, 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.
Littorinimorpha is a large order of snails, gastropods, consisting primarily of sea snails, but also including some freshwater snails and land snails.
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.
The Tonnidae are a family of medium-sized to very large sea snails, known as the tun shells. These are marine gastropod molluscs in the clade Littorinimorpha. The name "tun" refers to the snails' shell shape which resembles wine casks known as "tuns". While the shells are thin, they are also strong. There is no operculum. They are found in all tropical seas, where they inhabit sandy areas. During the day, they bury themselves in the substrate, emerging at night to feed on echinoderms, crustaceans, and bivalves. Some larger species also capture fish, using their expandable probosces to swallow them whole. Females lay rows of eggs that become free-swimming larvae for several months before settling to the bottom.
Tonna tankervillii is a very large species of sea snail or tun snail, a marine gastropod mollusc in the family Tonnidae, the tun shells.
Tonna tetracotula is a species of very large sea snail or tun snail, a marine gastropod mollusc in the family Tonnidae, the tun shells.
Tonna luteostoma is a species of large sea snail, a marine gastropod mollusc in the family Tonnidae, the tun snails or tun shells.
Tonna melanostoma is a species of large sea snail, a marine gastropod mollusc in the family Tonnidae, the tun shells.
Tonna galea, commonly known as the giant tun, is a species of marine gastropod mollusc in the family Tonnidae. This very large sea snail or tun snail is found in the North Atlantic Ocean as far as the coast of West Africa, in the Mediterranean Sea and the Caribbean Sea. The species was first described by Carl Linnaeus in 1758.
A land snail is any of the numerous species of snail that live on land, as opposed to the sea snails and freshwater snails. Land snail is the common name for terrestrial gastropod mollusks that have shells. However, it is not always easy to say which species are terrestrial, because some are more or less amphibious between land and fresh water, and others are relatively amphibious between land and salt water.
Tonna berthae is a species of large sea snail or tun snail, a marine gastropod mollusc in the family Tonnidae, the tun shells.
The Tonnoidea are a superfamily of sea snails, marine gastropod molluscs in the order Littorinimorpha. This superfamily includes many very large species.
Malea pomum, common name the Pacific grinning tun, is a species of large sea snail, a marine gastropod mollusk in the family Tonnidae, the tun shells.
Tonna allium, common name the costate tun, is a species of large sea snail, a marine gastropod mollusk in the family Tonnidae, the tun shells.
Tonna canaliculata is a species of large sea snail, a marine gastropod mollusk in the family Tonnidae, the tun shells.
Tonna dunkeri is a species of large sea snail, a marine gastropod mollusk in the family Tonnidae, the tun shells.
Tonna pennata is a large species of sea snail, a marine gastropod mollusc in the family Tonnidae, the tun shells. Commonly known as the Atlantic partridge tun, the species is a predator of animals much larger than itself, particularly sea cucumbers.
Tonna tessellata, the mosaic tun,tessellate tun or maculated tun, is a species of large sea snail, a marine gastropod mollusk in the family Tonnidae.
Tonna zonata is a species of large sea snail, a marine gastropod mollusk in the family Tonnidae, the tun shells.
Tonna chinensis, common name : the China tun, is a species of large sea snail, a marine gastropod mollusk in the family Tonnidae, the tun shells.
