Skip to Content

Marine Habitat Classification

Description of biotope or habitat type

To understand more about what this page is describing, see How to use the classification. See also How to cite.

   Arenicola marina in infralittoral fine sand or muddy sand

Physical habitat description

Salinity Full (30-35 ppt), Variable (18-35 ppt)
Wave exposure Moderately exposed, Sheltered, Very sheltered, Extremely sheltered
Tidal streams Moderately strong (1-3 kn), Weak (>1 kn), Very weak (negligible)
Substratum Fine to very fine sand and muddy sand
Zone Infralittoral
Depth Band 0-5 m, 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.Ssa.IMuSa.AreISa <I>Arenicola marina</I> in infralittoral fine sand or muddy sand

  • 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.


In shallow fine sand or non-cohesive muddy sand in fully marine conditions (or occasionally in variable salinity) a community characterised by the polychaete Arenicola marina may occur. This biotope appears quite faunally sparse. Those other taxa present however, include scavenging crustacea such as Pagurus bernhardus and Liocarcinus depurator, terebellid polychaetes such as Lanice conchilega and the burrowing anemone Cerianthus lloydii. Occasional Sabella pavonina and frequent Ensis spp. may also be observed in some areas. The majority of records for this biotope are derived from epifaunal surveys and consequently there is little information available for the associated infaunal species. It is possible that this biotope, like EcorEns (to which it is broadly similar) is an epibiotic overlay on other biotopes from the SSA complex.


No situation data available.

Temporal variation

At certain times of the year a diatom film may be present on the sediment surface.

Characterising species

Taxon Relative importance of taxon for defining this community (%) Typical abundance - SACFOR scale % of core records where taxon was recorded
Hydractinia echinata 1 Occasional 21-40 %
Cerianthus lloydii 2 Frequent 21-40 %
Capitella capitata 91 Common 61-80 %
Arenicola marina 9 Abundant 61-80 %
Arenicola marina 55 Common 81-100 %
Terebellidae 1 Occasional 21-40 %
Lanice conchilega 5 Occasional 41-60 %
Sabella pavonina 1 Occasional 21-40 %
Pagurus bernhardus 10 Occasional 61-80 %
Liocarcinus depurator 2 Occasional 21-40 %
Carcinus maenas 2 Occasional 21-40 %
Ensis 1 Frequent 21-40 %
Diatoms - film 9 Common 21-40 %

Similar biotopes or habitat types

AreISa is likely to be a shallow water extension of the littoral Arenicola biotope MacAre

Back to top