Description of biotope or habitat type
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Sponges, cup corals and anthozoans on shaded or overhanging circalittoral rock
Physical habitat description
| Salinity | Full (30-35 ppt) |
|---|---|
| Wave exposure | Exposed, Moderately exposed |
| Tidal streams | Moderately strong (1-3 kn), Weak (>1 kn) |
| Substratum | Bedrock |
| Zone | Circalittoral |
| Depth Band | 10-20 m, 20-30 m |
| Other Features | Overhangs; caves |
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.
- 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 occurs on shaded and overhanging rock, such as on cave walls and ceilings although there are very few records of caves in conditions not subject to wave surge (i.e. deeper circalittoral habitats) and almost all are different in species composition. There are also a few examples of similar communities on very deep (70-100 m+) upward-facing rock (in Loch Hourn) and more may be found through the use of ROVs. These often species-rich habitats are almost invariably adjacent to well-mixed turbulent water. Characteristic species include the sponges Stryphnus ponderosus, Dercitus bucklandi, Chelonaplysilla noevus, Pseudosuberites sp. and Spongosorites sp., the anemones Parazoanthus spp., the cup corals Leptopsammia pruvoti, Hoplangia durotrix, Caryophyllia inornatus and the soft coral Alcyonium coralloides. Thymosia guernei is sometimes present. This biotope is likely to need further splitting with further data and analysis.
Situation
Subtidal rocky coasts.
Temporal variation
Unknown.
Characterising species
| Taxon | Typical abundance - SACFOR scale | % of core records where taxon was recorded |
|---|---|---|
| Alcyonium coralloides | Occasional | 41-60% |
| Alcyonium glomeratum | Occasional | 41-60% |
| Aplysilla sulfurea | Occasional | 21-40% |
| Caryophyllia inornata | Occasional | 41-60% |
| Caryophyllia smithii | Common | 61-80% |
| Corynactis viridis | Common | 61-80% |
| Dercitus bucklandi | Occasional | 21-40% |
| Hoplangia durotrix | Occasional | 21-40% |
| Leptopsammia pruvoti | Occasional | 21-40% |
| Morchellium argus | Frequent | 41-60% |
| Pachymatisma johnstonia | Frequent | 41-60% |
| Parablennius gattorugine | Occasional | 21-40% |
| Parazoanthus anguicomus | Occasional | 21-40% |
| Parazoanthus axinellae | Occasional | 21-40% |
| Spongosorites | Occasional | 1-20% |
| Stelletta grubii | Common | 41-60% |
| Stryphnus ponderosus | Occasional | 1-20% |
| Thorogobius ephippiatus | Occasional | 41-60% |
| Thymosia guernei | Common | 21-40% |
Similar biotopes or habitat types
Not applicable or unknown.
Classification history of this biotope or habitat type
| Classification version | Code |
|---|---|
| 1996 (6.95) | CR.MCR.SCupPar |