MC1-253 - Paroi rocheuse calcaire verticale du circalittoral creusée par Hiatella en Atlantique

Hiatella-bored Atlantic circalittoral vertical limestone rock

Classification des habitats EUNIS 2022

Descriptif de l'habitat

Moderately exposed vertical and overhanging soft rock (typically chalk), subject to moderately strong to weak tidal streams, bored by the rock-boring mollusc Hiatella arctica. As with other biotopes in the soft rock complex, it is found in areas of high turbidity, where there is poor light penetration. There may be isolated clumps of the hydroid Nemertesia antennina and a sparse bryozoan turf formed by various crisiids, Bugula plumosa and Bugula flabellate (often being grazed on by the nudibranch Janolus cristatus), Alcyonidium diaphanum, Flustra foliacea and Cellapora pumicosa. A patchy 'carpet' of the brittlestar Ophiothrix fragilis is often recorded along with other echinoderms such as Asterias rubens and Henricia sanguinolenta. Other species present include the colonial ascidians Polyclinum aurantium, Botrylloides leachi, Clavelina lepadiformis, Aplidium punctatum and Botryllus schlosseri, dead mans fingers Alcyonium digitatum and the crab Cancer pagurus. Sponges present include the boring sponge Cliona celata, Halichondria panicea, Myxilla incrustans, Leucosolenia botryoides and Dysidea fragilis. Occasionally, the foliose red seaweed Delessaria sanguinea may be recorded.

Bibliography

European Topic Centre on Biological Diversity 2022. EUNIS marine habitat classification 2022 including crosswalks. Table Excel. (Source)