A seashell or sea shell, also known simply as a shell, is a hard, protective outer layer usually created by an animal or organism that lives in the sea. The shell is part of the body of the animal. Empty seashells are often found washed up on beaches by beachcombers. The shells are empty because the animal has died and the soft parts have decomposed or been eaten by another animal.
The gastropods, commonly known as snails and slugs, belong to a large taxonomic class of invertebrates within the phylum Mollusca called Gastropoda.
Nudibranchs are a group of soft-bodied marine gastropod molluscs which shed their shells after their larval stage. They are noted for their often extraordinary colours and striking forms, and they have been given colourful nicknames to match, such as "clown", "marigold", "splendid", "dancer", "dragon", or "sea rabbit". Currently, about 3,000 valid species of nudibranchs are known.
Sea slug is a common name for some marine invertebrates with varying levels of resemblance to terrestrial slugs. Most creatures known as sea slugs are gastropods, i.e. they are sea snails that over evolutionary time have either completely lost their shells, or have seemingly lost their shells due to having a greatly reduced or internal shell. The name "sea slug" is most often applied to nudibranchs, as well as to a paraphyletic set of other marine gastropods without obvious shells.
Opisthobranchs is now an informal name for a large and diverse group of specialized complex gastropods which used to be united in the subclass Opisthobranchia. That taxon is no longer considered to represent a monophyletic grouping.
The mantle is a significant part of the anatomy of molluscs: it is the dorsal body wall which covers the visceral mass and usually protrudes in the form of flaps well beyond the visceral mass itself.
The umbrella slug is a species of large sea snail or limpet, a marine gastropod mollusc in the family Umbraculidae. It is found in tropical to warm temperate parts of the Indo-Pacific and Atlantic Oceans, where it feeds on sponges.
Marine invertebrates are the invertebrates that live in marine habitats. Invertebrate is a blanket term that includes all animals apart from the vertebrate members of the chordate phylum. Invertebrates lack a vertebral column, and some have evolved a shell or a hard exoskeleton. As on land and in the air, marine invertebrates have a large variety of body plans, and have been categorised into over 30 phyla. They make up most of the macroscopic life in the oceans.
Chromodoris annae, commonly known as the Anna's magnificent slug, is a species of sea slug, a very colourful nudibranch, a shell-less marine gastropod mollusc in the family Chromodorididae.
Chromodoris magnifica is a sea slug, a species of nudibranch, a shell-less marine gastropod mollusc in the family Chromodorididae. It is the type species of the genus Chromodoris.
Elysia ornata, commonly known as ornate elysia or ornate leaf slug, is a species of sea slug, a marine gastropod mollusk. This sea slug superficially resembles a nudibranch, yet it does not belong to that suborder of gastropods. Instead it is a member of the closely related clade Sacoglossa, the "sap-sucking" sea slugs.
Cypraea tigris, commonly known as the tiger cowrie, is a species of cowry, a large sea snail, a marine gastropod mollusk in the family Cypraeidae, the cowries.
Chromodoris lochi, common name Loch's chromodoris, is a species of colourful sea slug, a dorid nudibranch, a marine gastropod mollusk in the family Chromodorididae.
Juliidae, common name the bivalved gastropods, is a family of minute sea snails, marine gastropod mollusks or micromollusks in the superfamily Oxynooidea, an opisthobranch group.
Chromodoris dianae is a species of sea slug, a dorid nudibranch, a shell-less marine gastropod mollusc in the family Chromodorididae.
Discodoris boholiensis, known commonly as the Bohol discodoris, is a species of sea slug in the family Discodorididae. It gets its name from the island of Bohol in the Philippines. Discodoris boholiensis has a distinctive pattern of chocolate brown and cream-white all over its flattened body and wavy-edged mantle. It reaches a length of 12 cm (5 in).
Chromodoris orientalis is a species of colourful sea slug, a dorid nudibranch, a marine gastropod mollusc in the family Chromodorididae. Sea slugs are generally very beautifully colored organisms with intense patterns and ranging in sizes. The Chromodoris orientalis specifically is a white sea slug with black spots in no particular pattern with a yellow, orange, or brown in color ring around its whole body and on its gills. There is much discussion on where it is found, what it eats, how it defends itself without a shell, and its reproduction methods. This is all sought after information because there is not much known about these animals.
Cuspivolva tigris, known commonly as the Tiger egg cowry, is a species of sea snail, a marine gastropod mollusk in the family Ovulidae, the ovulids, cowry allies or false cowries.
Berthella martensi is a species of sea slug, a marine gastropod mollusk in the family Pleurobranchidae.
Lamellaria perspicua, commonly known as the transparent lamellaria, is a species of small, slug-like sea snail, a marine gastropod mollusc in the family Velutinidae. It is native to the northeastern Atlantic Ocean and the Mediterranean Sea, where it feeds on colonial ascidians.
