2. Données et outils
  3. Rechercher un habitat
  4. MC4-214 - Flustra foliacea et Hydrallmania falcata sur du sédiment hétérogène du circalittoral soumis aux courants de marée
  5. Description
MC4-214 - Flustra foliacea et Hydrallmania falcata sur du sédiment hétérogène du circalittoral soumis aux courants de marée

Flustra foliacea and Hydrallmania falcataon tide-swept circalittoral mixed sediment
MC4-213 - Kurtiella bidentata et Thyasira spp. dans du sédiment hétérogène envasé du circalittoral
MC4-215 - Bancs d'ophiures Ophiothrix fragilis et/ou Ophiocomina nigra sur sédiment hétérogène du circalittoral

Classification des habitats EUNIS 2022

Descriptif de l'habitat

This biotope represents part of a transition between sand-scoured circalittoral rock where the epifauna is conspicuous enough to be considered as a biotope and a sediment biotope where an infaunal sample is required to characterise it and is possibly best considered an epibiotic overlay. Flustra foliacea and the hydroid Hydrallmania falcata characterise this biotope; lesser amounts of other hydroids such as Sertularia argentea, Nemertesia antennina and occasionally Nemertesia ramose, occur where suitably stable hard substrata is found. The anemone Urticina feline and the soft coral Alcyonium digitatum may also characterise this biotope. Barnacles Balanus crenatus and tube worms Pomatoceros triqueter may be present and the robust bryozoans Alcyonidium diaphanum and Vesicularia spinosa appear amongst the hydroids at a few sites. Sabella pavonina and Lanice conchilega may be occasionally found in the coarse sediment around the stones. In shallower (i.e. upper circalittoral) examples of this biotope scour-tolerant robust red algae such as Polysiphonia nigrescens, Calliblepharis spp. and Gracilaria gracilis are found.
Situation: This biotope is found around most coasts, although regional differences are seen where one or two similarly scour-tolerant species such as Styela clava and Crepidula fornicata (Solent) occupy the hard substrata

Bibliographie

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