Biology
(
الإنجليزية
)
المقدمة من Arkive
The sea-fan anemone reproduces asexually by shedding parts of its base behind it as it moves along. These fragments develop into tiny anemones (2), which are often closely packed together (3). This mode of reproduction means that this species has rather limited powers of dispersal. However, sexual reproduction probably does occur, and the wide distribution of this species suggests that there must be some form of dispersal as yet undetected (2). The lifespan is between 20 and 100 years (2).
Conservation
(
الإنجليزية
)
المقدمة من Arkive
The sea-fan anemone is a UK Biodiversity Action Plan (UK BAP) priority species, and as such, a Species Action Plan has been produced to guide its conservation (3). Although there is no conservation action currently targeted at this species, the main host in the British Isles, the rare pink sea fan (Eunicella verrucosa), is afforded full legal protection under Schedule 5 of the Wildlife and Countryside Act, 1981, and is therefore protected against killing, taking, injuring, and sale (3). The conservation of these two delicate and sensitive species is closely tied.
Description
(
الإنجليزية
)
المقدمة من Arkive
This small anemone is pink, orange, red or buff-coloured with streaks of white (2), and has up to around 80 irregularly arranged small tentacles (2). The scientific name of this group of sea anemones Amphianthus refers to their flower-like appearance; amphi means 'near' and anthus is from the Greek for flower, 'anthos' (4). It usually occurs attached to sea fans, hence the common name (2).
Habitat
(
الإنجليزية
)
المقدمة من Arkive
Attaches to sea fans such as the pink sea fan (Eunicella verrucosa) in England, the northern sea fan (Swiftia pallida) in Scotland, and similar organisms, and occurs in the 'sublittoral zone', inhabiting fairly deep water (2).
Range
(
الإنجليزية
)
المقدمة من Arkive
In Great Britain, this species is most often recorded off Plymouth. It has also been found off the west coast of Scotland, in Cornwall, and around Lundy Island in the Bristol Channel, and occurs around the south and southwest coasts of Ireland (2). In the rest of the world, it occurs along the Atlantic coast of France, reaching into the western Mediterranean (2). Throughout this range, the sea-fan anemone appears to be rare (3).
Status
(
الإنجليزية
)
المقدمة من Arkive
Not listed or protected by any conservation directives, conventions or legislation (3).
Threats
(
الإنجليزية
)
المقدمة من Arkive
Although this species has never been particularly common, it has nevertheless undergone a decline (3). A number of causes of this decline have been proposed, including changes in water masses; since the 1970s water masses have become colder, which has caused problems for species at the northernmost limit of their distribution (3). Furthermore, contamination of the water resulting from various human activities may affect larval and adult survival (3).
Amphianthus dohrnii
(
الإنجليزية
)
المقدمة من wikipedia EN
Amphianthus dohrnii, the sea fan anemone, is a species of sea anemone in the family Hormathiidae. It occurs in the northeastern Atlantic Ocean and Mediterranean Sea and grows on sea fans.
Distribution and habitat
Amphianthus dohrnii is native to the northeastern Atlantic Ocean and the western end of the Mediterranean Sea. It is scarce on the west coast of Scotland but more plentiful in southwestern Britain and in the western and southern parts of Ireland. It is present on the west coast of France and the westernmost parts of the Mediterranean at depths down to about 1,000 m (3,281 ft). It tolerates both strong and weak currents and both plenty of, and little, wave action.[2] It seems to grow exclusively on the stems of gorgonian corals, primarily the northern sea fan (Swiftia pallida) in the north of its range, and the pink sea fan (Eunicella verrucosa) in the south.[3]
Description
Amphianthus dohrnii is a small species, seldom exceeding 1 cm (0.4 in) in diameter, though the base, where it adheres to the substrate, may be up to 25 mm (1.0 in) long. It has about eighty short, tapering tentacles and is red, orange, pinkish or buff, with irregular translucent white markings.[4][5]
Biology
Reproduction is mostly by basal laceration, a form of asexual reproduction. The sea anemone crawls along a hard surface and pieces of tissue become detached and grow into new individuals. However, it is likely that sexual reproduction sometimes takes place, as otherwise this species would be unlikely to be so widely dispersed.[5] Amphianthus dohrnii was at one time common in both the Mediterranean and the English Channel, but it seems now to be absent from the former and increasingly rare in the latter.[6] In British waters, the sea fan Eunicella verrucosa has declined, possibly being damaged by dredging or in association with higher sea temperatures, and the already rare Amphianthus dohrnii has become scarcer.[7]
References
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^ a b Fautin, Daphne (2014). "Amphianthus dohrnii (Koch, 1878)". WoRMS. World Register of Marine Species. Retrieved 2014-12-13.
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^ Jackson, Angus (2009). "Sea fan anemone - Amphianthus dohrnii - Habitat preferences and distribution". MarLIN. Archived from the original on 2014-12-13. Retrieved 2014-12-13.
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^ Wilding, Catherine; Wilson, Emily (2009). "Northern sea fan - Swiftia pallida - General biology". MarLIN. Archived from the original on 2014-12-13. Retrieved 2014-12-13.
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^ Jackson, Angus (2009). "Sea fan anemone - Amphianthus dohrnii - General biology". MarLIN. Archived from the original on 2014-12-13. Retrieved 2014-12-13.
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^ a b "Sea-fan anemone Amphianthus dohrnii". ARKive. Archived from the original on 2014-12-17. Retrieved 2014-12-13.
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^ Sue Wells; IUCN Conservation Monitoring Centre; International Union for Conservation of Nature and Natural Resources; International Union for Conservation of Nature and Natural Resources. Species Survival Commission (1983). The IUCN invertebrate red data book. IUCN. p. 23.
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^ Hiscock, Keith; Southward, Alan; Tittley, Ian; Hawkins, Stephen (2004). "Effects of changing temperature on benthic marine life in Britain and Ireland". Aquatic Conservation. 14 (4): 333–362. doi:10.1002/aqc.628.
Amphianthus dohrnii: Brief Summary
(
الإنجليزية
)
المقدمة من wikipedia EN
Amphianthus dohrnii, the sea fan anemone, is a species of sea anemone in the family Hormathiidae. It occurs in the northeastern Atlantic Ocean and Mediterranean Sea and grows on sea fans.
Biology
(
الإنجليزية
)
المقدمة من World Register of Marine Species
on gorgonians
van der Land, J. (ed). (2008). UNESCO-IOC Register of Marine Organisms (URMO).
- ترخيص
- cc-by-4.0
- حقوق النشر
- WoRMS Editorial Board
Habitat
(
الإنجليزية
)
المقدمة من World Register of Marine Species
shelf to slope
van der Land, J. (ed). (2008). UNESCO-IOC Register of Marine Organisms (URMO).
- ترخيص
- cc-by-4.0
- حقوق النشر
- WoRMS Editorial Board
