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Marine Habitat Classification

Description of biotope or habitat type

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   Cordylophora caspia and Einhornia crustulenta on reduced salinity infralittoral rock

Physical habitat description

Salinity Reduced (18-30ppt), Low (<18ppt)
Wave exposure Very sheltered, Extremely sheltered
Tidal streams Strong (3-6 kn), Moderately strong (1-3 kn)
Substratum Boulders; cobbles
Zone Infralittoral
Depth Band 0-5 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 IR.LIR.IFaVS.CcasEin <I>Cordylophora caspia</I> and <I>Einhornia crustulenta</I> on reduced salinity infralittoral 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'
  • 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.


Shallow sublittoral rock in the upper estuary of one of the south-west inlets (Tamar) with very high turbidity and therefore no seaweeds. The brackish-water hydroid Cordylophora caspia and small colonies of the encrusting bryozoan Einhornia crustulenta and a few Balanus crenatus characterise this biotope. More information required to validate this description.


Insufficient information to describe neighbouring biotopes.

Temporal variation


Characterising species

Taxon Relative importance of taxon for defining this community (%) Typical abundance - SACFOR scale % of core records where taxon was recorded
Cordylophora caspia 98 Occasional 81-100%
Einhornia crustulenta 1 Frequent 41-60%
Balanus crenatus 1 Rare 41-60%

Similar biotopes or habitat types

Not applicable or unknown.

Classification history of this biotope or habitat type

Classification version Code
2015 (15.03) IR.LIR.IFaVS.CcasEle
1996 (6.95) SCR.HarCon (part)

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