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Marine Habitat Classification

Description of biotope or habitat type

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   Capitella capitata, Thyasira spp. and Ophryotrocha dubia in organically-enriched offshore circalittoral sandy mud

Physical habitat description

Salinity Full (30-35 ppt)
Wave exposure
Tidal streams
Substratum Sandy mud.
Zone Circalittoral
Depth Band
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.SMu.OMu.CapThy.Odub <I>Capitella capitata</I>, <I>Thyasira</I> spp. and <I>Ophryotrocha dubia</I> in organically-enriched offshore circalittoral sandy mud

  • 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 deep offshore sandy mud adjacent to oil or gas platforms, organic enrichment from drill cuttings leads to the development of communities dominated by the pollution tolerant opportunist Capitella capitata and the polychaete Ophryotrocha dubia (or other species of Ophryotrocha). These species are generally found in extremely high abundances and accompanied by Thyasira spp., Raricirrus beryli, Paramphinome jeffreysii and Chaetozone setosa. Other taxa including Exogone verugera, Pholoe inornata and Idasola simpsoni may also be present.


No situation data available.

Temporal variation

No temporal data available.

Characterising species

Characterising species data not applicable.

Similar biotopes or habitat types

CapThy is found in muddier sediment, in slightly more polluted areas and is slightly more diverse.

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