Polyides rotundus, Ahnfeltia plicata and Chondrus crispus on sand-covered Atlantic infralittoral rock

Description (English)

Low-lying rock surrounded by mobile sand and often subject to burying by the sand, with a turf of resilient red seaweeds Chondrus crispus, Polyides rotundus and Ahnfeltia plicata typically protruding through the sand on the upper surfaces of the rock. Other scour-tolerant seaweeds include Rhodomela confervoides, Phyllophora pseudoceranoides, Phyllophora crispa, Furcellaria lumbricalis, Gracilaria gracilis, Ceramium rubrum, Plocamium cartilagineum, Heterosiphonia plumosa, Cryptopleura ramosa and Dilsea carnosa. Coralline crusts typically cover the rock, while scattered individuals of the brown seaweeds Halidrys siliquosa, Cladostephus spongiosus, Dictyota dichotoma and Laminaria saccharina can be present. The large anthozoan Urticina felina can occur in this biotope but there are few other conspicuous animals.
Situation: This biotope occurs on shallow sand-covered rock, often below bedrock and boulders supporting kelp forest, which is above the effect of, sand scour (unit MB1-21A) or abutting sand-scoured kelp on bedrock (unit MB1-235). It may also be found adjacent to the shallow kelp and Chorda filum biotope (unit MB1-233) and similarly can be surrounded by a variety of sediment biotopes.

Source: EUNIS habitat classification