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3 results for 'CR.LCR.BrAs.NovPro'
CR.LCR.BrAs.NovPro Novocrania anomala and Protanthea simplex on sheltered circalittoral rock
This biotope typically occurs in full to variable salinity conditions on very wave-sheltered circalittoral bedrock and boulder slopes subject to negligible tidal streams (this tends to be in the landward, very sheltered basins of fjordic sealochs). This biotope is characterised by often dense populations of the anemone Protanthea simplex, growing on the silty bedrock. The underlying rock surfaces are usually covered by encrusting red algae, the polychaete Spirobranchus triqueter, the brachiopods Novocrania anomala and Terebratulina retusa, the saddle oyster Pododesmus patelliformis and the polychaete Sabella pavonina. Scattered colonies of Alcyonium digitatum and the hydroid Bougainvillia muscus may occasionally be recorded. A diverse range of ascidians including Ciona intestinalis, Ascidia mentula, Corella parallelogramma, Ascidia virginea, Polycarpa pomaria and Dendrodoa grossularia are also occasionally recorded. Echinoderms such as the common brittlestar Ophiothrix fragilis are frequently reported with their arms protruding from crevices in the rock, whilst the starfish Asterias rubens, Henricia oculata, and the sea urchin Echinus esculentus and Psammechinus miliaris are occasionally found on the boulder/rock surface. The whelk Buccinum undatum is often present but in very low numbers. The squat lobster Munida rugosa may be seen hiding in crevices. The hermit crab Pagurus bernhardus may also be recorded.
CR.LCR.BrAs.NovPro.FS Novocrania anomala and Protanthea simplex on very wave-sheltered circalittoral rock
This variant typically occurs on deep, lower circalittoral bedrock or boulder slopes (often-vertical walls) in the landward, very sheltered basins of fjordic sealochs. In these very sheltered conditions, there are frequently dense populations of the anemone Protanthea simplex growing on the silty boulder or rock slope, and on the tubes of the parchment worm Chaetopterus variopedatus. The underlying rock surfaces are usually covered with encrusting red algae, the polychaete Spirobranchus triqueter, the brachiopod Novocrania anomala, the saddle oyster Pododesmus patelliformis and the conspicuous fan worm Sabella pavonina. Scattered colonies of Alcyonium digitatum are occasionally present along with the hydroid Bougainvillia muscus. The barnacle Balanus balanus and the hermit crab Pagurus bernhardus is occasionally seen on boulder or rock surface, whilst underneath in crevices, the squat lobster Munida rugosa may be present. A diverse range of solitary ascidians, typically found in sheltered conditions, are often present including Ciona intestinalis, Corella parallelogramma, Polycarpa pomaria, Ascidia mentula and Ascidia virginea. Echinoderms such as brittlestars Ophiothrix fragilis are frequently seen with their arms protruding from crevices in the rock, whilst the starfish Asterias rubens, the sea urchin Echinus esculentus and Psammechinus miliaris are occasionally found on the boulder or rock surface. The whelk Buccinum undatum is often present but in very low numbers.
CR.LCR.BrAs.NovPro.VS Novocrania anomala, Dendrodoa grossularia and Rolandia coralloides on variable salinity circalittoral rock
This variant typically occurs on lower circalittoral silty, bedrock or boulder cliffs and ridges in very wave-sheltered fjordic sealochs subjected to variable salinity regimes (such as Loch Etive). In these sheltered conditions, there are frequently dense populations of the ascidian Dendrodoa grossularia, the brachiopod Novocrania anomala and to a lesser extent, the brachiopod Terebratulina retusa, which are able to tolerate the variable salinity. Other solitary ascidians that may be present include Ciona intestinalis, Corella parallelogramma, Ascidiella scabra, Ascidia mentula, Ascidia virginea and Polycarpa pomaria. The anemone Protanthea simplex is occasionally seen, although to a lesser extent than in NeoPro, possibly due to the variable salinity. The hydroids Bougainvillia muscus and Lafoea dumosa, the cup-coral Caryophilia smithii and Rolandia coralloides are occasionally present. The tubes formed by the polychaete Sabella pavonina may be observed standing erect from the rock surface. The rest of the rock surface is usually covered by encrusting red algae and the polychaete Spirobranchus triqueter and Protula tubularia. The sea cucumber Psolus phantapus may be found on the underside of boulders. Other species such as the hermit crab Pagurus bernhardus and the spider crab Hyas araneus may be found amongst the rock/boulders. The starfish Asterias rubens, Crossaster papposus, and Henricia spp. and the sea urchin Psammechinus miliaris are also recorded within this variant. The relatively bare, silty rock supports low numbers of a relatively few species. Although barren rock grazed by the sea urchin Echinus esculentus is found in other sea loch biotopes (see FaAlCr.Pom and FaAlCr.Car), E.esculentus is virtually absent within NeoPro.VS.