Fucus spiralis on full salinity exposed to moderately exposed upper eulittoral rock

Description (English)

Exposed to moderately exposed upper eulittoral bedrock characterised by a band of the spiral wrack Fucus spiralis overlying the black lichen Verrucaria maura and the olive green lichen Verrucaria mucosa. Underneath the fronds of F. spiralis is a community consisting of the limpet Patella vulgata, the winkles Littorina saxatilis and Littorina littorea, the mussel Mytilus edulis and the barnacle Semibalanus balanoides. The whelk Nucella lapillus can be found in cracks and crevices preying on the mussels and barnacles. During the summer months ephemeral green seaweeds such as Enteromorpha intestinalis can be common. The insect Anurida maritima can be present in this zone taking shelter in cracks and crevices when the tide comes in.
Situation: This zone usually lies below a zone dominated by the wrack Pelvetia canaliculata (unit A1.211), but occasional clumps of P. canaliculata may be present (usually less than common) amongst the F. spiralis. This unit occurs above the wrack Fucus vesiculosus (A1.213) zones. Vertical surfaces in this zone, especially on moderately exposed shores, often lack the fucoids and are characterised by a barnacle-limpet dominated community (unit A1.113).

Source: EUNIS habitat classification