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Marine Habitat Classification


Description of biotope or habitat type

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   Ulothrix flacca and Urospora spp. on freshwater-influenced vertical littoral fringe soft rock


Habitat (physical) description

Salinity Full (30-35 ppt)
Wave exposure Moderately exposed
Tidal streams
Substratum Bedrock
Zone Littoral fringe
Depth Band
Other Features Vertical soft rock

Download comparative physical and biological data. The comparative tables enable a rapid comparison of the species composition and principal physical characteristics between a given set of biotopes.

Distribution of habitat LR.FLR.Lic.UloUro <I>Ulothrix flacca</I> and <I>Urospora</I> spp. on freshwater-influenced vertical littoral fringe soft rock

  • Records used to define the biotope (core records)
  • Other records assigned to this biotope, marked as 'certain'
  • Other records assigned to this biotope, marked as 'uncertain'

Point data based on records in the UK Marine Recorder Snapshot.

Description

An assemblage of the small un-branched filamentous green seaweeds Ulothrix flacca, Urospora penicilliformis and Urospora wormskioldii at High Water Spring Tide level on steep and vertical rock often influenced by freshwater. The community is also present in areas with freshwater seepage. It is visually recognised as a closely adherent, often shiny, green mat of filamentous growth. Associated species include the green seaweeds Blidingia minima and Enteromorpha prolifera, the barnacle Semibalanus balanoides and the limpet Patella vulgata, but these species are not common. Although this biotope does occur on rock other than chalk, this description has been derived from chalk coast sites. More information is needed to improve this description.

Situation

On chalk coasts this community can include Enteromorpha spp. and the transition from UloUro to Ent is often indistinct and a mixed zone of UloUro and Ent can occur.

Temporal variation

This biotope is more easily identifiable from autumn to spring as both Urospora spp. and Bangia atropurpurea may dry out and disappear during the summer. In late winter the red seaweed B. atropurpurea may be predominant and the community then appears as shiny blackish mats of filamentous growth.

Characterising Species

Taxon Relative importance of taxon for defining this community (%) Typical abundance - SACFOR scale % of core records where taxon was recorded
Polydora 7 Occasional 61-80 %
Semibalanus balanoides 7 61-80 %
Patella vulgata 7 61-80 %
Ulothrix 36 Occasional 81-100 %
Ulothrix flacca 1 21-40 %
Urospora penicilliformis 1 21-40 %
Urospora wormskioldii 9 Frequent 61-80 %
Enteromorpha 34 Rare 81-100 %

Similar biotopes

LR.FLR.Lic.Bli
Vertical soft rock in the littoral fringe characterised by a band of the foliose green seaweeds B. minima and Blidingia marginata. The filamentous, un-branched green seaweeds U. flacca and Urospora spp. may be present in this biotpe.

LR.FLR.Eph.Ent
Occurs on the lower shore and is characterised by Enteromorpha sp.

Biotope history

Classification Habitat code
6.95 LRK.UU

Photos

LR.FLR.LIC.UloUro Ulothrix flacca and Urospora spp. on freshwater-influenced vertical littoral fringe soft rock, Unspecified location. ANON © JNCC
LR.FLR.LIC.UloUro Ulothrix flacca and Urospora spp. on freshwater-influenced vertical littoral fringe soft rock, Unspecified location. ANON © JNCC

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