Skip to Content

Marine Habitat Classification


1 result for 'CR.HCR.FaT.CTub.CuSp'

   CR.HCR.FaT.CTub.CuSp  Tubularia indivisa and cushion sponges on tide-swept turbid circalittoral bedrock

This variant is typically found on the vertical and upper faces of strongly tide-swept, exposed circalittoral bedrock and boulders. It is commonly associated with areas where turbidity levels are high for much of the year, for example, around Anglesey and the Lleyn Penisula. From afar, this variant appears as a dense carpet of Tubularia indivisa covering tide-swept gully walls, floors and boulders. T. indivisa is frequently observed growing through sheets of sponges such as Myxilla incrustans and Halichondria panicea as well as through dense patches of the barnacle Balanus crenatus and tubes of the amphipod Jassa spp. Several other species of sponge appear to be tolerant of the high turbidity in areas where this variant occurs, many of which are common in other biotopes. These include Amphilectus fucorum, Pachymatisma johnstonia, Hemimycale columella, Dysidea fragilis and Clathrina coriacea. Robust hydroids (other than T. indivisa) such as Nemertesia antennina and Sertularia argentea occur in patches. The anemones Urticina felina, Actinothoe sphyrodeta and Cylista elegans are typically common. A short bryozoan turf consisting of crisiid bryozoans, Alcyonidium diaphanum, Bicellariella ciliata, Bugulina turbinata and Bugulina flabellata may be present. Alcyonium digitatum may occasionally be seen although it doesn't tend to be as dominant as in CTub.Adig. Individual Corynactis viridis may be seen scattered across the gully walls and boulders. The starfish Henricia oculata may be seen on boulders and gully floors whilst typical under-boulder fauna includes the crab Cancer pagurus.
Back to top