Ivell's sea anemone (''Edwardsia ivelli'') is a species of sea anemone in the family Edwardsiidae. It is

endemic Endemism is the state of a species being found in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also found else ...

to a single location, Widewater Lagoon in

West Sussex West Sussex is a county in South East England on the English Channel coast. The ceremonial county comprises the shire districts of Adur, Arun, Chichester, Horsham, and Mid Sussex, and the boroughs of Crawley and Worthing. Covering an ...

, England, where it was first discovered by Richard Ivell. It has been listed as Data Deficient by the IUCN since 1996.

Description

Ivell's sea anemone is a tiny, worm-like anemone up to long and diameter; the column is similar to other ''

Edwardsia ''Edwardsia'' is a genus of sea anemones, the type of the family Edwardsiidae. They have eight mesenteries and live in tubes in the sand. The name, in New Latin, commemorates the French zoologist Henri Milne-Edwards Henri Milne-Edwards (23 O ...

'' spp. There are twelve transparent tentacles, arranged in two cycles, nine tentacles in the outer cycle and three in the inner cycle. In life the tentacles of the outer cycle are held flat on the substrate, the three of the inner cycle more or less vertical, often curled over the mouth. Each tentacle has a few transverse bars of pale cream occasionally forming complete rings.

Distribution

It is endemic to England known from only one site, Widewater Lagoon in West Sussex, the type locality. Searches in recent years have failed to find any specimens and the species is considered extinct by some conservationists

Habitat

Burrows in soft mud in saline lagoons or sheltered creeks, it is a tiny species and easily overlooked unless deliberately sought.

Similar species

Although the type of locality inhabited by this species is not often searched by divers such places are well worth investigating. This species and ''

Nematostella vectensis The starlet sea anemone (''Nematostella vectensis'') is a species of small sea anemone in the family Edwardsiidae native to the east coast of the United States, with introduced populations along the coast of southeast England and the west coast o ...

'' are probably the only British Anthozoans which can be considered endangered species through habitat destruction and pollution. Ivell's sea anemone was discovered by Professor Richard Ivell, hence the species' name.Manuel, R.L. (1975). A new sea anemone from a brackish lagoon in Sussex, ''Edwardsia ivelli'', sp. nov. Journal of Natural History, 9, 705-711.

References

{{Taxonbar, from=Q2124204 Edwardsia Endemic fauna of England Cnidarians of the Atlantic Ocean Anthozoa of Europe Marine fauna of Europe Environment of West Sussex Animals described in 1975 1975 in England Taxonomy articles created by Polbot