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.
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.
Hexaplex cichoreum, common name the "endive murex", is a medium-sized species of sea snail, a marine gastropod mollusk in the family Muricidae, the murex shells or rock snails.
Ellobium is a genus of medium-sized, air-breathing, saltmarsh snails, terrestrial pulmonate gastropod mollusks in the family Ellobiidae.
Conasprella aphrodite is a species of sea snail, a marine gastropod mollusk in the family Conidae, the cone snails and their allies.
Conus cuneolus is a species of sea snail, a marine gastropod mollusk in the family Conidae, the cone snails and their allies.
Conus fragilissimus, common name the fragile geography cone, is a species of sea snail, a marine gastropod mollusk in the family Conidae, the cone snails and their allies.
Conus marchionatus, common name the Marquesas cone, is a species of sea snail, a marine gastropod mollusk in the family Conidae, the cone snails and their allies.
Conus milesi is a species of sea snail, a marine gastropod mollusk in the family Conidae, the cone snails and their allies.
Conus pseudonivifer is a species of sea snail, a marine gastropod mollusk in the family Conidae, the cone snails and their allies.
Conus purpurascens, common name the purple cone, is a species of sea snail, a marine gastropod mollusk in the family Conidae, the cone snails and their allies.
Conus rufimaculosus, also known as the red-stained cone, is a species of sea snail, a marine gastropod mollusk in the family Conidae, the cone snails and their allies.
Conus saragasae is a species of sea snail, a marine gastropod mollusk in the family Conidae, the cone snails and their allies.
Conus violaceus, common name the tendineus cone, is a species of sea snail, a marine gastropod mollusk in the family Conidae, the cone snails and their allies.
Hexaplex regius, common name: the regal murex, is a species of sea snail, a marine gastropod mollusk in the family Muricidae, the murex snails or rock snails.
Monoplex pilearis, common name the hairy triton, is a species of medium-sized predatory sea snail, a marine gastropod mollusk in the family Cymatiidae.
Muricopsinae is a taxonomic subfamily of predatory sea snails, marine gastropod mollusks within the large family Muricidae, the murex snails and rock snails.
Tegula brunnea, common name the brown turban snail, is a species of medium-sized sea snail, a marine gastropod mollusk in the family Tegulidae,.
Acteon tornatilis, common name the "lathe acteon", is a species of medium-sized sea snail, a predatory marine gastropod mollusc in the family Acteonidae, the barrel bubble snails.
