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Marine Habitat Classification

Description of biotope or habitat type

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   Nephtys hombergii, Macoma balthica and Streblospio shrubsolii in littoral sandy mud

Physical habitat description

Salinity Variable (18-35 ppt)
Wave exposure Sheltered, Very sheltered, Extremely sheltered
Tidal streams
Substratum Sandy mud
Depth Band Lower shore, Mid shore
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 LS.LMu.MEst.NhomMacStr <I>Nephtys hombergii</I>, <I>Macoma balthica</I> and <I>Streblospio shrubsolii</I> in littoral 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'

Point data based on records in the UK Marine Recorder Snapshot.


Soft mud with a fine sand fraction, in variable salinity conditions, typically close to the head of estuaries. The infauna is dominated by the polychaete worm Streblospio shrubsolii, the polychaete Nephtys hombergii, oligochaetes of the genus Tubificoides, and the Baltic tellin Macoma balthica. The ragworm Hediste diversicolor and the spire shell Peringia ulvae are often common or abundant.


NhomMacStr occurs in mid estuary conditions, usually on the low shore. Tben and Hed.Ol may occur higher up the shore, as well as further towards the upper estuary.

Temporal variation

Enteromorpha spp. and Ulva lactuca may form mats on the surface of the mud during the summer months, particularly in areas of nutrient enrichment.

Characterising species

Taxon Relative importance of taxon for defining this community (%) Typical abundance - SACFOR scale Typical abundance - (count per m2) % of core records where taxon was recorded
Peringia ulvae 43 Abundant 5093 81-100%
Streblospio shrubsolii 13 Common 593 81-100%
Macoma balthica 12 Common 373 81-100%
Tubificoides 12 Common 662 41-60%
Tubificoides benedii 10 Common 999 81-100%
Nephtys hombergii 6 Abundant 133 61-80%
Hediste diversicolor 1 Common 124 41-60%

Similar biotopes or habitat types

Occurs in lower salinities, in mud with a smaller sand fraction, at the head of estuaries. The infauna is a lot poorer, consisting almost exclusively of oligochaetes and, in some cases, Capitella capitata.

Tends to occur in more reduced salinities, further towards the head of estuaries. The polychaete assemblage is poorer, and molluscs are virtually absent. It is the presence of M. balthica and H. ulvae that primarily distinguishes LS.LMu.MEst.NhomMacStr from LS.LMu.UEst.Hed.Ol.

These communities occur further down estuaries towards the open coast, in more saline conditions. The infauna is similar, though the ragworm H. diversicolor is always abundant, and both N. hombergii and S. shrubsolii are often absent. The bivalve assemblage tends to be more diverse.

Classification history of this biotope or habitat type

Classification version Code
2015 (15.03) LS.LMu.MEst.NhomMacStr
1997 (97.06) LMU.MU.HedStr (part)

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