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 Parerythropodium coralloides. Thymosia guernei is sometimes present. This biotope is likely to need further splitting with further data and analysis. Situation: Subtidal rocky coasts.