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2 results for 'SS.SBR.SMus.ModMvar'
SS.SBR.SMus.ModMvar Modiolus modiolus beds with Mimachlamys varia, sponges, hydroids and bryozoans on slightly tide-swept very sheltered circalittoral mixed substrata
Dense Modiolus modiolus beds, covered by hydroids and bryozoans, on soft gravelly, shelly mud with pebbles in areas of slight or moderate tidal currents. The variable scallop (Mimachlamys varia) is frequently found in large numbers amongst the Modiolus shells. Hydroids such as Halecium spp. and Kirchenpaueria pinnata and ascidians such as Ascidiella aspersa, Corella parallelogramma and Ciona intestinalis may be found attached to pebbles or mussel shells. The echinoderms Ophiothrix fragilis and Antedon bifida are often frequent in this biotope as is the encrusting polychaete Spirobranchus triqueter. Similar communities have been found on cobble and pebble plains in stable, undisturbed conditions in some sea lochs, although not all these examples have Modiolus beds.
SS.SBR.SMus.ModT Modiolus modiolus beds with hydroids and red seaweeds on tide-swept circalittoral mixed substrata
Modiolus beds on mixed substrata (cobbles, pebbles and coarse muddy sediments) in moderately strong currents or wave exposed areas, typically on the open coast but also in tide-swept channels of marine inlets. Ophiothrix fragilis are often common in this biotope along with the calcareous tubes of Spirobranchus triqueter, anemones such as Alcyonium digitatum and Urticina felina and hydroids such as Abietinaria abietina and Sertularia argentea. Buccinum undatum may also be important and in some areas the clam Mimachlamys varia may be frequent but not in the same abundances as in SS.SBR.SMus.ModMvar. Little information on the infaunal component is given here although it is likely that it is very rich and may highlight more subtle differences in the Modiolus biotopes. This biotope is typified by examples off the north-west Lleyn Peninsula in north Wales and off Co. Down, Northern Ireland.