Biodiversity & Conservation

Hydroids, ephemeral seaweeds and Littorina littorea in shallow eulittoral mixed substrata pools


Hydroids, ephemeral seaweeds and <i>%Littorina littorea%</i> in shallow eulittoral mixed substrata pools
Distribution map

LR.FLR.Rkp.H recorded (dark blue bullet) and expected (light blue bullet) distribution in Britain and Ireland (see below)

Text page icon Habitat description

Map icon Distribution of biotope in Britain and Ireland LR.H has not been recorded in Ireland. In Scotland, it has only been recorded at Devil's Thrashing Floor, Dumfries & Galloway. On the south Devon coast it is found near Brixham. On the west coasts it has been recorded near Port Talbot in Wales and at Duddon Sands and St Bees Head in Cumbria. It has also been recorded on the north coast of Norfolk and near Blackwater Estuary in Essex.
National importance Rare

Text page icon Description of biotope

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

Shallow pools on mixed cobbles, pebbles, gravel and sand may be colonized by hydroids (Obelia longissima and Kirchenpaueria pinnata), ephemeral green algae (Ulva sp.) and the winkle Littorina littorea. Within these pools, patches of sand may be occupied by the lugworm Arenicola marina and sand mason worms Lanice conchilega. These pools are often associated with mussel beds (SLR.MytX), with Mytilus edulis also present in the pools. Barnacles (Semibalanus balanoides and Elminius modestus) and the keel worm Pomatoceros triqueter may be attached to shells and small stones. (Information taken from the Marine Biotope Classification for Britain and Ireland, Version 97.06: Connor et al., 1997a, b).

Additional information icon Additional information

This review can be cited as follows:

Marshall, C.E. 2005. Hydroids, ephemeral seaweeds and Littorina littorea in shallow eulittoral mixed substrata pools. Marine Life Information Network: Biology and Sensitivity Key Information Sub-programme [on-line]. Plymouth: Marine Biological Association of the United Kingdom. [cited 29/11/2015]. Available from: <>