The gastropod shell is part of the body of many gastropods, including snails, a kind of mollusc. The shell is an exoskeleton, which protects from predators, mechanical damage, and dehydration, but also serves for muscle attachment and calcium storage. Some gastropods appear shell-less (slugs) but may have a remnant within the mantle, or in some cases the shell is reduced such that the body cannot be retracted within it (semi-slug). Some snails also possess an operculum that seals the opening of the shell, known as the aperture, which provides further protection. The study of mollusc shells is known as conchology. The biological study of gastropods, and other molluscs in general, is malacology. Shell morphology terms vary by species group.
Pleurotomariidae, common name the "slit snails", is a family of large marine gastropods in the superfamily Pleurotomarioidea of the subclass Vetigastropoda. This family is a very ancient lineage; there were numerous species in the geological past. The genus includes several hundred fossil forms, mostly Paleozoic. It is one of the oldest gastropod families, commencing in the Cambrian.
Vetigastropoda is a major taxonomic group of sea snails, marine gastropod mollusks that form a very ancient lineage. Taxonomically the Vetigastropoda are sometimes treated as an order, although they are treated as an unranked clade in Bouchet and Rocroi, 2005.
Anatoma crispata is a species of minute sea snail, a marine gastropod mollusk or micromollusk in the family Anatomidae.
Sukashitrochus morleti is a species of minute sea snail, a marine gastropod mollusc in the family Scissurellidae.
Danilia telebathia is a species of small sea snail, a marine gastropod mollusc in the family Chilodontaidae.
Turbo heterocheilus is a species of sea snail, marine gastropod mollusk in the family Turbinidae.
Microgaza is a genus of sea snails, marine gastropod mollusks in the family Solariellidae.
Olivella riverae is a species of small sea snail, marine gastropod mollusk in the subfamily Olivellinae, in the family Olividae, the olives. Species in the genus Olivella are commonly called dwarf olives.
Callogaza watsoni is a species of sea snail, a marine gastropod mollusk in the family Margaritidae.
Clanculus guineensis is a species of sea snail, a marine gastropod mollusk in the family Trochidae, the top snails.
Gaza superba, common name the superb gaza, is a species of deep sea sea snail, a marine gastropod mollusc in the family Margaritidae.
Gibbula multicolor, common name the multicoloured topshell, is a species of sea snail, a marine gastropod mollusk in the family Trochidae, the top snails.
Trochus maculatus, common name the maculated top shell, is a species of sea snail, a marine gastropod mollusk in the family Trochidae, the top snails.
Callogaza is a genus of sea snails, marine gastropod mollusks in the family Margaritidae.
Clanculus johnstoni is a species of sea snail, a marine gastropod mollusk in the family Trochidae, the top snails.
Coelotrochus viridis, common name the green top shell, is a species of sea snail, a marine gastropod mollusk in the family Trochidae, the top snails.
Gaza daedala is a species of sea snail, a marine gastropod mollusc in the family Margaritidae.
Halystina umberlee is a species of very small deep-water sea snail, a marine gastropod mollusc in the family Seguenziidae.
Aliculastrum exaratum is a species of gastropods belonging to the family Haminoeidae.
