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Concept: Sponges and shade-tolerant red seaweeds on overhanging lower eulittoral bedrock and in cave entrances in the eunishabitats vocabulary

Concept URI http://eunis.eea.europa.eu/eunishabitats/A1.446
Preferred label Sponges and shade-tolerant red seaweeds on overhanging lower eulittoral bedrock and in cave entrances
Definition Overhanging shaded bedrock on the open lower shore and at the entrance to inner reaches of caves (where light availability permits), which is not subject to appreciable wave-surge, characterised by a shade-tolerant red seaweed community. It includes foliose species such as [Plumaria plumosa, Palmaria palmata, Mastocarpus stellatus, Membranoptera alata] and [Osmundea pinnatifida], but [Lomentaria articulata] and coralline crusts are usually present as well. The foliose green seaweed [Ulva lactuca] can be present. The rock surface often supports dense populations of calcareous tube-forming polychaetes [Spirorbis] spp. and [Pomatoceros] spp., while sponges such as [Grantia compressa], [Halichondria panicea] and [Hymeniacidon perleve] can be common. The hydroid [Dynamena pumila] (normally found on fucoids) hangs in distinct form from overhanging rock. Colonies of the ascidian [Botryllus schlosseri] can be found on the rock, along with the mussel [Mytilus edulis] and the barnacles [Semibalanus balanoides] and [Balanus perforatus] (the latter may occur at high densities in the south and west), while the anemone [Actinia equina] thrives in the permanently damp pits and crevices. The whelk [Nucella lapillus] can be found among the barnacles and mussels, preying on them. The long list of characterising species is partly due to the difference in the species composition and does not solely reflect a high species richness. Situation: On overhangs, this biotope is generally found above the SByAs biotope, where there is more light available. In cave environments, SR may be found at the entrance to and inner reaches of the cave, extending from the lower walls (above the SByAs biotope) to the upper walls (depending on the height of the cave). Further into the cave where less light is available the ascidian [Dendrodoa grossularia] can be abundant (SR.Den).
Notation A1.446
Status Valid
Status Modified 2014-01-31
Accepted Date 2014-01-31
Not Accepted Date
Has broader
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Has exact match