Fucus spiralis on sheltered variable salinity upper eulittoral rock
Sheltered to extremely sheltered upper eulittoral bedrock or mixed substrata (boulders, large cobbles or shells on mud) in variable salinity conditions characterised by a band of the spiral wrack Fucus spiralis. The ephemeral green seaweed Enteromorpha intestinalis is usually found in this species poor biotope. The barnacles Semibalanus balanoides and Elminius modestus can be found where suitable substrata are available, while gammarids can be found underneath the fronds of F. spiralis and/or underneath the boulders and cobbles. Also found underneath the fronds and among the boulders are the winkles Littorina saxatilis and Littorina littorea and the crab Carcinus maenas.
Situation: This zone usually lies below a zone dominated by the wrack Pelvetia canaliculata (unit MA1-23B) and occasional clumps of P. canaliculata may be present (usually less than common) amongst the F. spiralis. In areas of extreme shelter and variable salinity conditions (e.g. in Scottish sea lochs), the P. canaliculata and F. spiralis zones often merge together forming a very narrow band. This unit occurs above the wracks Ascophyllum nodosum (MA1-254) and/or Fucus vesiculosus (MA1-253) zones and these two fucoids may also occur, although F. spiralis always dominates. It can also be found above a zone dominated by the wrack Fucus ceranoides (MA1-257).
Temporal variation: During the summer months ephemeral green seaweeds such as E. intestinalis can be common.
Source: EUNIS habitat classification
|EUNIS habitat type||code MA1252|
|Relation to||Resolution 4 habitat type (used for designation of Emerald sites)|
Relation to other habitat types mentioned in legal instruments
Relation to vegetation types (syntaxa)Not available
Species mentioned in habitat description
|Species scientific name||English common name||Species group|
|Classification||Code||Habitat type name||Relationship type|
|EUNIS Habitat Classification 2007 (revised descriptions 2012)||A1.322||Fucus spiralis on sheltered variable salinity upper eulittoral rock||same|
|Classification||Code||Habitat type name||Relationship type||Comment|
|EUNIS Habitat Classification 200410||A1.322||Fucus spiralis on sheltered variable salinity upper eulittoral rock||same|
|EUNIS Habitat Classification 200308||A1.312||Fucus spiralis on moderately exposed to very sheltered upper eulittoral rock||wider|
|EUNIS Habitat Classification 200202||A1.312||Fucus spiralis on moderately exposed to very sheltered upper eulittoral rock||same|
|EUNIS Habitat Classification 199910||A1.312||Fucus spiralis on moderately exposed to very sheltered upper eulittoral rock||same|
|MNCR BioMar 97.06 (Britain & Ireland)||SLR.F.Fspi||Fucus spiralis on moderately exposed to very sheltered upper eulittoral rock||same|