Gastropoda
Cypraea chinensis
Scientific classification
Kingdom:	Animalia
Phylum:	Mollusca
Class:	Gastropoda Cuvier, 1795
Subclasses
Patellogastropoda Vetigastropoda Neomphalina Neritomorpha Caenogastropoda Heterobranchia

Limpets, mussels and barnacles on a rock in the intertidal zone.

Gastropods, or univalves, are the largest and most successful class of molluscs. 60,000–75,000 known living species belong to it. Most of are marine, but many live in freshwater or on land. Their fossil record goes back to the later Cambrian.

Slugs and snails, abalones, limpets, cowries, conches, top shells, whelks, and sea slugs are all gastropods. The gastropods are in origin sea-floor predators, though they did evolve into many other habitats.

Many lines living today evolved in the Mesozoic era, taking advantage of the huge supply of food on the sea floor's continental shelves.