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Concept: [Caryophyllia smithii], [Swiftia pallida] and large solitary ascidians on exposed or moderately exposed circalittoral rock in the eunishabitats vocabulary

Concept URI http://eunis.eea.europa.eu/eunishabitats/A4.2112
Preferred label [Caryophyllia smithii], [Swiftia pallida] and large solitary ascidians on exposed or moderately exposed circalittoral rock
Definition This variant typically occurs on exposed to moderately wave-exposed, circalittoral bedrock and boulders rock subject to mainly weak tidal streams and has a thin layer of silt present. It is found predominantly from 10-30m water depth. From afar, this biotope is mostly distinguished by the frequently occurring seafan [Swiftia pallida], encrusting red algae and the abundant cup coral [Caryophyllia smithii]. This biotope has quite an impoverished appearance, compared with SwiLgAs which has a strong sponge component. Other species present are typically in low abundance. Echinoderms such as [Echinus esculentus], [Antedon bifida], [Antedon petasus], [Leptometra celtica], [Marthasterias glacialis], [Luidia ciliaris] and [Asterias rubens] may be recorded. Large hydroids such as [Nemertesia antennina] and [Nemertesia ramosa] may occasionally be seen in isolated clumps on the tops of boulders and rocky outcrops. The anthozoan [Parazoanthus anguicomus] may be recorded. Bryozoans such as [Parasmittina trispinosa] and [Porella compressa] are occasionally observed. The polychaete [Pomatoceros triqueter] may be observed encrusting the sides of rocks and boulders while occasional [Alcyonium digitatum] may also be seen. A small suite of large ascidians may be present, including [Ascidia mentula], [Clavelina lepadiformis], [Ciona intestinalis], [Diazona violacea] and [Ascidia virginea]. Sponges are typically absent from this biotope, although [Cliona celata] may be recorded occasionally. The top shell [Gibbula cineraria] is usually present. Under boulders and overhangs, the squat lobster [Munida rugosa] can usually be seen hiding. All these records are from the west coast of Scotland (East coast of Lewis /Outer Hebrides). Situation: Above this biotope in the infralittoral zone, sheltered kelp forests are usually found, with species such as [Laminaria hyperborea], [Laminaria saccharina] and [Sacchoriza polyschides]. This biotope is found on bedrock and boulders, which may either be protruding from the surrounding sediment, or the sediment may be in a separate zone below the bedrock. These sediments may either be deep mud (with species such as [Pachycerianthus] and [Nephrops] ) on the sheltered sites or slightly coarser sediments (with [Pennatula] and [Virgularia]) on slightly more exposed sites.
Notation A4.2112
Status Valid
Status Modified 2014-01-31
Accepted Date 2014-01-31
Not Accepted Date
Has broader
Has exact match