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Marine Habitat Classification

Description of biotope or habitat type

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   Sabellaria spinulosa encrusted circalittoral rock

Physical habitat description

Salinity Full (30-35 ppt)
Wave exposure Exposed, Moderately exposed
Tidal streams Moderately strong (1-3 kn), Weak (>1 kn), Very weak (negligible)
Substratum Bedrock, boulders, cobbles
Zone Circalittoral
Depth Band 10-20 m, 20-30 m, 30-50 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 CR.MCR.CSab.Sspi <I>Sabellaria spinulosa</I> encrusted circalittoral rock

  • 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.


This biotope is typically found encrusting the upper faces of wave-exposed and moderately wave-exposed circalittoral bedrock, boulders and cobbles subject to strong/moderately strong tidal streams in areas with high turbidity. The crusts formed by the sandy tubes of the polychaete worm Sabellaria spinulosa may even completely cover the rock, binding the substratum together to form a crust. A diverse fauna may be found attached to, and sometimes obscuring the crust, often reflecting the character of surrounding biotopes. Bryozoans such as Flustra foliacea, Pentapora foliacea and Alcyonidium diaphanum, anemones such as Urticina felina and Cylista elegans, the polychaete Spirobranchus triqueter, Alcyonium digitatum, the hydroid Nemertesia antennina and echinoderms such as Asterias rubens and Crossaster papposus may all be recorded within this biotope. There are two variants. The first (Sspi.ByB) contains significant cover of barnacles (Balanus crenatus) and bryozoans. The second (Sspi.As) has a dense turf of didemnid ascidians as well as scour-tolerant bryozoans such as F. foliacea, sponges such as Tethya aurantium and Phorbas fictitius, colonies of the serpulid worm Salmacina dysteri and patchy occurrences of the ascidians Distomus variolosus, Polycarpa pomaria and Polycarpa scuba. This biotope has been recorded from the Lleyn Peninsula, Lundy Island (including the wreck of the MV Robert) and the north-east and south coast of England.


No situation data available.

Temporal variation

No temporal variation data available.

Characterising species

Taxon Relative importance of taxon for defining this community (%) Typical abundance - SACFOR scale % of core records where taxon was recorded
Sabellaria spinulosa 30 Common 81-100%
Didemnidae 12 Frequent 41-60%
Flustra foliacea 8 Occasional 61-80%
Asterias rubens 7 Occasional 61-80%
Urticina felina 5 Occasional 41-60%
Alcyonium digitatum 3 Frequent 21-40%
Distomus variolosus 3 Common 21-40%
Spirobranchus triqueter 3 Frequent 21-40%
Crossaster papposus 2 Occasional 21-40%
Pentapora foliacea 2 Occasional 21-40%
Polycarpa pomaria 2 Common 21-40%
Alcyonidium diaphanum 1 Occasional 21-40%
Balanus crenatus 1 Frequent 21-40%
Nemertesia antennina 1 Occasional 21-40%
Phorbas fictitius 1 Occasional 21-40%
Polycarpa scuba 1 Common 21-40%
Cylista elegans 1 Occasional 21-40%
Salmacina dysteri 1 Occasional 21-40%
Tethya aurantium 1 Occasional 21-40%

Similar biotopes or habitat types

Not applicable or unknown.

Classification history of this biotope or habitat type

Classification version Code
1997 (97.06) CR.MCR.CSab.Sspi


CR.MCR.CSab.Sspi Sabellaria spinulosa encrusted circalittoral rock, E of Saltwick Nab, Whitby. JNCC©JNCC
CR.MCR.CSab.Sspi Sabellaria spinulosa encrusted circalittoral rock, E of Saltwick Nab, Whitby. JNCC©JNCC

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