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Concept: Solitary ascidians, including [Ascidia mentula] and [Ciona intestinalis], with [Antedon] spp. on wave-sheltered circalittoral rock in the eunishabitats vocabulary

Concept URI http://eunis.eea.europa.eu/eunishabitats/A4.3111
Preferred label Solitary ascidians, including [Ascidia mentula] and [Ciona intestinalis], with [Antedon] spp. on wave-sheltered circalittoral rock
Definition This variant occurs on circalittoral bedrock or boulder slopes in generally wave-sheltered conditions (often in sea lochs) with little tidal flow. It is frequently found on vertical or steeply-sloping rock. Apart from the large ascidians, [Ascidia mentula] and [Ciona intestinalis], the rock surface usually has a rather sparse appearance. Scyphistomae larvae are often present on any vertical surfaces. Grazing by the sea urchin [Echinus esculentus] leaves only encrusting red algae (giving the bedrock/boulder substratum a pink appearance), cup corals [Caryophyllia smithii] and the keelworm [Pomatoceros triqueter]. There may be a few hydroid species present, such as [Nemertesia] spp. and [Kirchenpaueria pinnata], occasional [Alcyonium digitatum] and occasional [Metridium senile]. Barnacles [Balanus] spp. and the colonial ascidian [Clavelina lepadiformis] also occasionally occur. At some sites, echinoderms such as the crinoid [Antedon] spp., the starfish [Crossaster papposus] and [Asterias rubens] and the brittlestar [Ophiothrix fragilis] (in low densities) may be found. The squat lobster [Munida rugosa] is likely to be found in crevices, under boulders, and the hermit crab [Pagurus bernhardus] may be observed moving around the rock surface. The brachiopod [Neocrania anomala] is frequently observed (especially where this biotope occurs shallower than NeoPro for example). The saddle oyster [Pododesmus patelliformis] may occasionally be seen attached to the rock/boulder face. Situation: This biotope is typical of one found in sheltered sealochs. On slightly more wave and tide exposed sites, a transition to the more diverse AntAsH biotope will occur. Below AmenCio.Ant, you may find the NeoPro biotope (especially situated on the sills of sealochs). Temporal variation: The abundance of [C. intestinalis] tends to fluctuate seasonally, so it may appear absent at a site at one time of year and then be present at other times, altering the visual appearance of the biotope. Other solitary ascidian species such as [A. mentula] and [Ascidiella aspersa] tend to be longer-lived (approximately 7 years and 3 years respectively).
Notation A4.3111
Status Valid
Status Modified 2014-01-31
Accepted Date 2014-01-31
Not Accepted Date
Has broader
Has exact match