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Marine Habitat Classification

Description of biotope or habitat type

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   Virgularia mirabilis and Ophiura spp. with Pecten maximus on circalittoral sandy or shelly mud

Physical habitat description

Salinity Full (30-35 ppt)
Wave exposure Moderately exposed, Sheltered, Very sheltered
Tidal streams Weak (>1 kn), Very weak (negligible)
Substratum Sandy mud; shelly and gravelly mud
Zone Circalittoral
Depth Band 5-10 m, 10-20 m, 20-30 m
Other Features

Biotope origin

Derived using data from Various
Faunal group Epifauna

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.CSaMu.VirOphPmax <I>Virgularia mirabilis</I> and <I>Ophiura</I> spp. with <I>Pecten maximus</I> on circalittoral sandy or shelly 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.


Circalittoral fine sandy mud may contain Virgularia mirabilis and Ophiura spp. A variety of species may occur, and species composition at a particular site may relate, to some extent, to the proportions of the major sediment size fractions. Several species are common to most sites including Virgularia mirabilis which is present in moderate numbers, Ophiura albida and Ophiura ophiura which are often quite common, and Pecten maximus which is usually only present in low numbers. Virgularia mirabilis is usually accompanied by occasional Cerianthus lloydii, Liocarcinus depurator and Pagurus bernhardus. Amphiura chiajei and Amphiura filiformis may occur in some examples of this biotope. Polychaetes and bivalves are generally the main components of the infauna, although the nemerteans, Edwardsia claparedii, Phoronis muelleri and Labidoplax buski may also be widespread. Of the polychaetes Goniada maculata, Nephtys incisa, Prionospio cirrifera, Chaetozone setosa, Notomastus latericeus and Owenia fusiformis are often the most widespread species whilst Myrtea spinifera, Lucinoma borealis, Kurtiella bidentata, Abra alba and Varicorbula gibba are typical bivalves in this biotope. This biotope is primarily identified on the basis of its epifauna and may be an epibiotic overlay over other closely related biotopes such as SS.SMu.CFiMu.SpnMeg, SS.SMu.CSaMu.AfilKurAnit and SS.SMu.CSaMu.AfilEten.


Such sediments are very common in sea lochs, often occurring shallower than the finest mud or in somewhat more exposed parts of the lochs.

Temporal variation

No temporal data available.

Characterising species

Taxon Relative importance of taxon for defining this community (%) Typical abundance - SACFOR scale % of core records where taxon was recorded
Virgularia mirabilis 24 Frequent 81-100%
Asterias rubens 11 Occasional 61-80%
Cerianthus lloydii 11 Occasional 61-80%
Pagurus bernhardus 7 Occasional 41-60%
Liocarcinus depurator 6 Occasional 61-80%
Pecten maximus 6 Occasional 61-80%
Ophiura albida 5 Frequent 41-60%
Ophiura ophiura 4 Frequent 41-60%
Turritellinella tricarinata 3 Occasional 21-40%
Amphiura filiformis 2 Common 21-40%
Arenicola marina 2 Occasional 21-40%
Lanice conchilega 2 Occasional 21-40%
Amphiura chiajei 1 Common 21-40%
Chaetopterus variopedatus 1 Occasional 21-40%
Seraphsidae 1 Occasional 21-40%
Echinus esculentus 1 Rare 21-40%

Similar biotopes or habitat types

SS.SMu.CFiMu.SpnMeg is found on finer muddier sediment and may be characterised by frequent Nephrops norvegicus and other megafaunal species.

SS.SMu.CSaMu.VirOphPmax.HAs has greater quantities of stones and shells on the surface which give rise to more sessile epibenthic species and distinguish this sub biotope.

Classification history of this biotope or habitat type

Classification version Code Habitat name
2015 (15.03) SS.SMu.CSaMu.VirOphPmax Virgularia mirabilis and Ophiura spp. with Pecten maximus on circalittoral sandy or shelly mud
2004 (04.05) SS.SMu.CSaMu.VirOphPmax Virgularia mirabilis and Ophiura spp. with Pecten maximus on circalittoral sandy or shelly mud
1997 (97.06) SS.CMS.VirOph Virgularia mirabilis and Ophiura spp. on circalittoral sandy or shelly mud

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