| Concept URI | http://eunis.eea.europa.eu/eunishabitats/A4.312 |
|---|---|
| Preferred label | Large solitary ascidians and erect sponges on wave-sheltered circalittoral rock |
| Definition | A4.312 is characteristic of the wave-sheltered conditions found in the Kenmare River on the west coast of Ireland. This biotope is typically found on silty circalittoral bedrock and boulders in wave-sheltered channels subject to varying amounts of tidal flow. These fully marine inlets and channels have steep, often vertical sides with small terraces or ledges. This biotope, characterised by erect sponges and large solitary ascidians, appears to be biologically diverse. A diverse ascidian fauna is generally present, including [Ascidia mentula], [Aplidium punctum], [Corella parallelogramma], [Ascidia virginea], [Botryllus schlosseri], [Clavelina lepadiformis] and [Ciona intestinalis]. An equally diverse sponge fauna, with massive erect sponges particularly noticeable, compliments these species. Dominant species include [Esperiopsis fucorum], [Dysidea fragilis], [Tethya aurantium], [Polymastia boletiformis], [Raspailia ramosa], [Stelligera stuposa], [Polymastia mamilliaris] and [Pachymatisma johnstonia]. Other sponges present are [Suberites carnosus], [Haliclona fistulosa], [Stelligera rigida], [Mycale rotalis], [Haliclona simulans], [Iophon hyndmani] and [Hemimycale columella]. Various sponge crusts may also be present but in most cases in lower abundances. Other significant components of the community include the cup coral [Caryophyllia smithii] and various echinoderms, including the sea urchin [Echinus esculentus] and the starfish [Henricia oculata] and [Marthasterias glacialis]. Small isolated clumps of [Nemertesia antennina] and individual [Alcyonium digitatum] may be seen, whilst the top shell [Calliostoma zizyphinum] may also be present. At present, there are relatively few records in this biotope, as it is only reported from around the south-western coast of Ireland, where sponge diversity is very high. Situation: Due to the sheltered nature of the biotope, LgAsSp is usually situated on bedrock/boulder outcrops associated with mud slopes and plains. Typical species found within these circalittoral muds include the seapen [Virgularia mirablis] and the anemone [Pachycerianthus multiplicatus]. In the infralittoral zone, sheltered kelp biotopes such as LsacX with [Laminaria saccharina] occur frequently. In areas where there is a slightly stronger tidal-stream, the circalittoral muddy plains become more muddy gravel plains and slopes. Typical species found within these habitats include the anemones [Mesacmaea mitchellii] and [Aureliana heterocera]. When tidal-streams becomes negligible, but with similar wave-sheltered conditions, you tend to find CarSwi.Aglo biotopes occurring, especially in the same geographical location (around south-west/west Ireland) as LgAsSp. |
| Notation | A4.312 |
| Status | Valid |
| Status Modified | 2014-01-31 |
| Accepted Date | 2014-01-31 |
| Not Accepted Date | |
| Has broader | |
| Has exact match |
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