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Marine Habitat Classification

Description of biotope or habitat type

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   Levinsenia gracilis and Heteromastus filifirmis in offshore circalittoral mud and sandy mud

Physical habitat description

Salinity Full (30-35 ppt)
Wave exposure
Tidal streams
Substratum Mud and 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.LevHet <I>Levinsenia gracilis</I> and <I>Heteromastus filifirmis</I> in offshore circalittoral mud and 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 mud and sandy mud a community characterised by the polychaetes Levinsenia gracilis and Heteromastus filiformis may occur. Other important taxa may include Paramphinome jeffreysii, Nephtys hystricis and N. incisa, Spiophanes kroyeri, Orbinia norvegica, Terebellides stroemi, Thyasira gouldi and T. equalis. Burrowing megafauna such as Calocaris macandreae may also be found in this biotope. This biotope has been found in the central and northern North Sea. A similar community, dominated by L. gracilis but accompanied by Glycera spp. (particularly Glycera rouxii) and Monticellina dorsobranchialis, has also been reported from the Irish Sea. This Irish community also contains Calocaris macandreae, Mediomastus fragilis, Tubificoides amplivasatus, Nephtys incisa, Ancistrosyllis groenlandica, Nucula sulcata, Litocorsa stremma and Minuspio sp. and it is not known at present whether this represents a separate biotope or whether it is a geographic variant of a wider Levinsenia biotope.


This biotope has been found in the central and northern North Sea and may also occur in the Irish Sea

Temporal variation

No temporal data available.

Characterising species

Characterising species data not applicable.

Similar biotopes or habitat types

Not applicable or unknown.

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