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Marine Habitat Classification

Description of biotope or habitat type

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   Nephtys cirrosa and Bathyporeia spp. in infralittoral sand

Physical habitat description

Salinity Full (30-35 ppt)
Wave exposure Exposed, Moderately exposed
Tidal streams Weak (>1 kn), Very weak (negligible)
Substratum Medium to very fine sand
Zone Infralittoral
Depth Band 0-5 m, 5-10 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.IFiSa.NcirBat <I>Nephtys cirrosa</I> and <I>Bathyporeia</I> spp. in infralittoral 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.


Well-sorted medium and fine sands characterised by Nephtys cirrosa and Bathyporeia spp. (and sometimes Pontocrates spp.) which occur in the shallow sublittoral to at least 30 m depth. This biotope occurs in sediments subject to physical disturbance, as a result of wave action (and occasionally strong tidal streams). The magelonid polychaete Magelona mirabilis may be frequent in this biotope in more sheltered, less tideswept areas whilst in coarser sediments the opportunistic polychaete Chaetozone setosa may be commonly found. The faunal diversity of this biotope is considerably reduced compared to less disturbed biotopes (such as FfabMag) and for the most part consists of the more actively-swimming amphipods. Sand eels Ammodytes sp. may occasionally be observed in association with this biotope (and others) and spionid polychaetes such as Spio filicornis and S. martinensis may also be present. Occasional Lanice conchilega may be visible at the sediment surface.


No situation data available.

Temporal variation

Stochastic recruitment events in the Nephtys cirrosa populations may be very important to the population size of other polychaetes present and may therefore create a degree of variation in community composition (Bamber 1994).

Characterising species

Taxon Relative importance of taxon for defining this community (%) Typical abundance - SACFOR scale % of core records where taxon was recorded
Polychaeta 4 21-40 %
Nephtys cirrosa 43 Common 81-100 %
Nephtys hombergii 1 21-40 %
Scoloplos armiger 1 21-40 %
Spio filicornis 1 Frequent 21-40 %
Spio martinensis 1 21-40 %
Spiophanes bombyx 2 21-40 %
Magelona mirabilis 15 Frequent 61-80 %
Chaetozone setosa 5 Common 41-60 %
Lanice conchilega 57 Occasional 41-60 %
Pontocrates arenarius 2 Frequent 21-40 %
Bathyporeia elegans 14 Frequent 41-60 %
Bathyporeia guilliamsoniana 5 Frequent 21-40 %
Crangon crangon 5 Rare 21-40 %
Pagurus bernhardus 8 Occasional 21-40 %
Liocarcinus depurator 8 Occasional 21-40 %
Fabulina fabula 1 21-40 %
Echinocardium cordatum 4 21-40 %
Ammodytes tobianus 8 Rare 21-40 %
Pomatoschistus 8 Occasional 21-40 %

Similar biotopes or habitat types

The current biotope is very similar to NcirMac, which occurs in reduced/variable salinities with additional reduced salinity fauna.

AmSco.Pon is closely allied to NcirBat but occurs in the intertidal zone

Po is closely allied to NcirBat but occurs in the intertidal zone

As sediment disturbance increases NcirBat may grade into IMoSa with only the most robust species able to tolerate the mobile sand environment

As sediment disturbance decreases and the finer silt fraction can begin to sediment out of the water column NcirBat may grade into the muddy sand biotope FfabMag.

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