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Marine Habitat Classification


Description of biotope or habitat type

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   Caryophyllia smithii, sponges and crustose communities on wave-exposed circalittoral rock


Habitat (physical) description

Salinity Full (30-35 ppt)
Wave exposure Extremely exposed, Very exposed, Exposed, Moderately exposed
Tidal streams Moderately strong (1-3 kn), Weak (>1 kn), Very weak (negligible)
Substratum Bedrock, boulders
Zone Circalittoral
Depth Band 10-20 m, 20-30 m, 30-50 m
Other Features

Download comparative physical and biological data. The comparative tables enable a rapid comparison of the species composition and principal physical characteristics between a given set of biotopes.

Distribution of habitat CR.MCR.EcCr.CarSp <I>Caryophyllia smithii</I>, sponges and crustose communities on wave-exposed circalittoral rock

  • Records used to define the biotope (core records)
  • Other records assigned to this biotope, marked as 'certain'
  • Other records assigned to this biotope, marked as 'uncertain'
  • Predicted extent of the level 3 (for sublittoral rock & deep sea) or 4 (for sublittoral sediment) habitat

Point data based on records in the UK Marine Recorder Snapshot. Predicted habitat extent is from UKSeaMap.

Description

This biotope typically occurs on the upper and vertical faces of wave-exposed, moderately strong to weakly tide-swept, circalittoral bedrock or boulders, with a water depth range of 20-30m. This often silty biotope has a typically sparse fauna, appearing grazed, and is characterised by common cup corals Caryophyllia smithii, frequent Alcyonium digitatum and occasional urchins Echinus esculentus. There may be occasional large growths of the sponge Cliona celata, Haliclona viscosa, Pachymatisma johnstonia and the axinellid sponge Stelligera stuposa. Echinoderms form a prominent feature of the fauna within this biotope, with species such as Marthasterias glacialis, Asterias rubens, Luidia ciliaris, Henricia oculata, Holothuria forskali, Antedon bifida and Aslia lefevrei present. Bryozoan crusts such as Parasmittina trispinosa and encrusting red algae cover the rock/boulder surface. The bryozoan Porella compressa may also be recorded occasionally. Isolated clumps of hydroids feature species such as Nemertesia antennina, Nemertesia ramosa, Abietinaria abietina, Halecium halecinum and Sertularella gayi. Other species observed include the anemone Corynactis viridis, Urticina felina, Sagartia elegans, Calliostoma zizyphinum, Balanus crenatus and Pomatoceros triqueter. Two variants within this biotope have been distinguished: CarSp.PenPcom and CarSp.Bri. While CarSp.PenPcom tends to have the bryozoans Pentapora foliacea and P. compressa, while CarSp.Bri features a dynamic community of brittlestars covering the seabed in a dense mat. Ophiothrix fragilis is usually the dominant species in shallow water but tends to be replaced by Ophiocomina nigra in deeper water.

Situation

No situation data available.

Temporal variation

No temporal variation data available.

Characterising Species

Taxon Relative importance of taxon for defining this community (%) Typical abundance - SACFOR scale % of core records where taxon was recorded
Pachymatisma johnstonia 1 Occasional 41-60 %
Stelligera stuposa 1 Occasional 41-60 %
Cliona celata 6 Frequent 81-100 %
Haliclona viscosa 3 Occasional 61-80 %
Halecium halecinum 1 Occasional 41-60 %
Abietinaria abietina 2 Frequent 41-60 %
Sertularella gayi 1 Occasional 41-60 %
Nemertesia antennina 3 Occasional 61-80 %
Nemertesia ramosa 2 Occasional 41-60 %
Alcyonium digitatum 6 Frequent 81-100 %
Urticina felina 2 Occasional 41-60 %
Sagartia elegans 1 Occasional 41-60 %
Corynactis viridis 4 Frequent 61-80 %
Caryophyllia smithii 9 Frequent 81-100 %
Pomatoceros triqueter 1 Occasional 41-60 %
Balanus crenatus 1 Frequent 41-60 %
Calliostoma zizyphinum 3 Occasional 61-80 %
Porella compressa 1 Occasional 21-40 %
Parasmittina trispinosa 4 Frequent 61-80 %
Antedon bifida 2 Frequent 41-60 %
Luidia ciliaris 3 Occasional 61-80 %
Henricia oculata 3 Occasional 61-80 %
Asterias rubens 4 Occasional 61-80 %
Marthasterias glacialis 4 Occasional 61-80 %
Echinus esculentus 6 Occasional 81-100 %
Holothuria forskali 2 Occasional 41-60 %
Aslia lefevrei 2 Occasional 41-60 %
Corallinaceae 2 Frequent 41-60 %

Similar biotopes

Not applicable or unknown.

Photos

CR.MCR.ECCR.CarSp Caryophyllia smithii, sponges and crustose communities on wave-exposed circalittoral rock, Dubh Sgeir, entrance to loch, Loch Tamanavay, Lewis. Sue Hiscock © JNCC
CR.MCR.ECCR.CarSp Caryophyllia smithii, sponges and crustose communities on wave-exposed circalittoral rock, Dubh Sgeir, entrance to loch, Loch Tamanavay, Lewis. Sue Hiscock © JNCC

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