Biodiversity & Conservation

Musculus discors beds on moderately exposed circalittoral rock


<i>%Musculus discors% </i>beds on moderately exposed circalittoral rock
Distribution map

CR.MCR.CMus.Mdis recorded (dark blue bullet) and expected (light blue bullet) distribution in Britain and Ireland (see below)

  • EC_Habitats

Text page icon Habitat description

Map icon Distribution of biotope in Britain and Ireland An uncommon biotope only recorded from Pappa Westray, Orkney; north Pembrokeshire, the Lleyn Peninsula and Anglesey in Wales, and Glandore Bay, Rathlin O'Birne, Kilkieran Bay and Carnsore Point in Ireland.
National importance Uncommon

Text page icon Description of biotope

For a full description of this biotope including characterizing species, distribution, survey information and references visit JNCC

Musculus discors beds on moderately exposed rock (with mucous-congealed mats of silt/pseudofaeces). A variety of sponges, hydroids and bryozoans typical of the open coast situation in the area may also be present such as Phorbas fictitius, Hemimycale columella, Polymastia boletiformis and Pentapora fascialis, together with Urticina felina, Salmacina dysteri and Balanus crenatus. Some of the sites with this biotope are exposed to moderately strong tides such as found near Maen Mellt on the Llyn Peninsula. (Information taken from the Marine Biotope Classification for Britain and Ireland, Version 97.06: Connor et al., 1997a, b).

Additional information icon Additional information

Although several surveys of this biotope are available (for example Cabioch, 1968; Hiscock, 1984; Könnecker & Keegan, 1983; Baldock et al., 1998; JNCC, 1999), little information on the ecology of the biotope was found.

This review can be cited as follows:

Tyler-Walters, H. 2002. Musculus discors beds on moderately exposed circalittoral rock. Marine Life Information Network: Biology and Sensitivity Key Information Sub-programme [on-line]. Plymouth: Marine Biological Association of the United Kingdom. [cited 25/11/2015]. Available from: <>