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Marine Habitat Classification

Description of biotope or habitat type

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   Laminaria saccharina with red and brown seaweeds on lower infralittoral muddy mixed sediment

Physical habitat description

Salinity Full (30-35 ppt)
Wave exposure Moderately exposed, Sheltered, Very sheltered, Extremely sheltered
Tidal streams Moderately strong (1-3 kn), Weak (>1 kn), Very weak (negligible)
Substratum Muddy gravelly mixed sediment
Zone Infralittoral - lower, Infralittoral
Depth Band 5-10 m, 10-20 m
Other Features

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 SS.SMp.KSwSS.LsacR.Mu <I>Laminaria saccharina</I> with red and brown seaweeds on lower infralittoral muddy mixed sediment

  • 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'
  • Predicted extent of the level 3 (for sublittoral rock & deep sea) or 4 (for sublittoral sediment) habitat

Point data based on records in the UK Marine Recorder Snapshot. Predicted habitat extent is from UKSeaMap.


Slightly deeper kelp community in the lower infralittoral, found on sandy gravelly mud, in sheltered and very sheltered conditions, with very weak tidal currents. The community is characterised by occasional Laminaria saccharina with an undergrowth of red and brown algae. Characteristic red seaweeds, as with other LsacR biotopes include Plocamium cartilagineum and Phycodrys rubens. However, the sheltered conditions of this biotope allow the 'Trailliella' phase of Bonnemaisonia hamifera to develop (although not to the extent of forming distinct mats as in SMP.Tra), and the related species Bonnemaisonia asparagoides. Brown algal species present, as with other LsacR biotopes, include Desmarestia spp at low abundance. The ubiquitous green seaweed Ulva sp. may also be present. The muddy substrate is home to a variety of typical mud dwelling fauna including the burrowing anemone Cerianthus lloydii. The gravelly component of this biotope provides a substrate for encrusting species such as the polychaete Pomatoceros triqueter and coralline encrusting algae.


No situation data available.

Temporal variation

No temporal data available.

Characterising species

Taxon Relative importance of taxon for defining this community (%) Typical abundance - SACFOR scale % of core records where taxon was recorded
Cerianthus lloydii 5 Occasional 61-80 %
Terebellidae 4 Occasional 41-60 %
Lanice conchilega 2 Occasional 41-60 %
Pomatoceros triqueter 2 Occasional 41-60 %
Pagurus bernhardus 8 Occasional 61-80 %
Liocarcinus depurator 5 Occasional 61-80 %
Gibbula magus 2 Occasional 41-60 %
Gibbula cineraria 2 Occasional 41-60 %
Pecten maximus 2 Occasional 41-60 %
Asterias rubens 7 Occasional 61-80 %
Ophiura albida 2 Occasional 41-60 %
Echinus esculentus 3 Occasional 41-60 %
Pomatoschistus minutus 1 Occasional 21-40 %
Bonnemaisonia asparagoides 2 Frequent 41-60 %
Corallinaceae 1 Occasional 21-40 %
Plocamium cartilagineum 2 Occasional 41-60 %
Delesseria sanguinea 1 Occasional 21-40 %
Phycodrys rubens 3 Occasional 41-60 %
Brongniartella byssoides 1 Frequent 21-40 %
Trailliella intricata 2 Occasional 21-40 %
Desmarestia aculeata 1 Occasional 21-40 %
Desmarestia viridis 2 Occasional 41-60 %
Laminaria saccharina 8 Occasional 81-100 %
Ulva 1 Occasional 21-40 %

Similar biotopes or habitat types

Similar species composition, however the two differ in their sediment characteristics and therefore in their infaunal communities.

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