This habitat type occurs on moderately wave-exposed, circalittoral soft bedrock subject to moderately strong tidal streams. As this complex is found in highly turbid water conditions, the circalittoral zone may begin at the low water mark, due to poor light penetration. This complex is dominated by the piddock Pholas dactylus. Other species typical of this complex include the polychaete Polydora and Bispira volutacornis, the sponges Cliona celata and Suberites ficus, the bryozoan Flustra foliacea, Alcyonium digitatum, the starfish Asterias rubens, the mussel Mytilus edulis and the crab Necora puber and Cancer pagurus. Foliose red algae may also be present. Please note: in areas subject to very high turbidity, biotopes within this habitat type may occur in the infralittoral and even the littoral zone.