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 actually 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.
Notarchus is a genus of sea slugs or sea hares, marine opisthobranch gastropod mollusks in the family Aplysiidae, the sea hares.
Syphonota geographica, or the geographic sea hare, is a species of sea slug or sea hare, a marine opisthobranch gastropod mollusk in the family Aplysiidae, the sea hares.
Sacoglossa, commonly known as the sacoglossans or the "sap-sucking sea slugs", are a clade of small sea slugs and sea snails, marine gastropod mollusks that belong to the clade Heterobranchia. Sacoglossans live by ingesting the cellular contents of algae, hence the adjective "sap-sucking".
Elysia subornata is a species of small sea slug, a marine opisthobranch gastropod mollusk in the family Plakobranchidae.
Elysia chlorotica is a small-to-medium-sized species of green sea slug, a marine opisthobranch gastropod mollusc. This sea slug superficially resembles a nudibranch, yet it does not belong to that clade of gastropods. Instead it is a member of the clade Sacoglossa, the sap-sucking sea slugs. Some members of this group use chloroplasts from the algae they eat for photosynthesis, a phenomenon known as kleptoplasty. Elysia chlorotica is one of these "solar-powered sea slugs". It lives in a subcellular endosymbiotic relationship with chloroplasts of the marine heterokont alga Vaucheria litorea.
Elysia is a genus of sea slugs, marine gastropod molluscs in the family Plakobranchidae. These animals are colorful sea slugs, and they can superficially resemble nudibranchs, but are not very closely related to them. Instead they are sacoglossans, commonly known as sap-sucking slugs.
Elysia crispata, common name the lettuce sea slug, is a large and colorful species of sea slug, a marine gastropod mollusk.
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.
Elysia catulus is a small species of sea slug, a marine gastropod mollusc in the family Plakobranchidae. This sea slug resembles a nudibranch, but it is not closely related to that order of gastropods, instead it is a sacoglossan. The specific name "catulus" comes from the Greek and means "little cat", referring to the superficial resemblance that the head of this slug bears to the head of a cat.
Elysia lobata is a species of sea slug, a marine gastropod mollusc in the family Plakobranchidae. This sea slug resembles a nudibranch, but it is not closely related to that order of gastropods, instead it is a sacoglossan.
Elysia australis is a species of sea slug, a marine gastropod mollusc in the family Plakobranchidae. This sea slug resembles a nudibranch, but it is not closely related to that order of gastropods, instead it is a sacoglossan. It occurs in Australia.
Elysia obtusa is a species of sea slug, a marine gastropod mollusc in the family Plakobranchidae. This sea slug resembles a nudibranch but is not closely related to that order of gastropods, instead it is a sacoglossan.
Elysia diomedea is a species of sea slug, a marine gastropod mollusc in the family Plakobranchidae.
Elysia trisinuata is a species of sea slug, a marine gastropod mollusc in the family Plakobranchidae. This sea slug resembles a nudibranch but is not closely related to that order of gastropods, instead belonging to another clade, Sacoglossa, the "sap-sucking" sea slugs.
Elysia rufescens is a species of sea slug, a marine gastropod mollusc in the family Plakobranchidae. This sea slug resembles a nudibranch but is not classified in that order of gastropods, instead belonging to a closely related clade, Sacoglossa, the "sap-sucking" sea slugs. This species was first described by Pease from Tahiti in 1871.
Elysia serca, the seagrass elysia or Caribbean seagrass elysia, is a species of sea slug, a marine gastropod mollusc in the family Plakobranchidae. Although this sea slug resembles a nudibranch, it is not a nudibranch; it belongs to the clade, Sacoglossa, the "sap-sucking" sea slugs. It was first described by Marcus in 1955 from specimens found in Brazil.
Elysia bangtawaensis is a species of sea slug, a marine gastropod mollusc in the family Plakobranchidae. Although this sea slug resembles a nudibranch, it is not a nudibranch but is part of a rather different clade, the sacoglossans, also known as the "sap-sucking" sea slugs.
Elysia grandifolia is a species of sea slug, a marine gastropod mollusc in the family Plakobranchidae native to the waters off southern India and Sri Lanka. It has colonised the waters of the eastern Mediterranean Sea.
