Description of biotope or habitat type
To understand more about what this page is describing, see How to use the classification. See also How to cite.
Circalittoral fine mud
Physical habitat description
Salinity | Full (30-35 ppt), Variable (18-35 ppt) |
---|---|
Wave exposure | Moderately exposed, Sheltered, Very sheltered, Extremely sheltered |
Tidal streams | Weak (>1 kn), Very weak (negligible) |
Substratum | Mud |
Zone | Circalittoral |
Depth Band | 10-20 m, 20-30 m, 30-50 m |
Other Features |
Biotope origin
Derived using data from | Various |
Faunal group | Epifauna/infauna |
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.

- 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.
Description
Sublittoral muds, occurring below moderate depths of 15-20 m, either on the open coast or in marine inlets such as sea lochs. The seapens Virgularia mirabilis and Pennatula phosphorea are characteristic of this biotope complex together with the burrowing anemone Cerianthus lloydii and the ophiuroid Amphiura spp. The relatively stable conditions often lead to the establishment of communities of burrowing megafaunal species, such as Nephrops norvegicus.
Situation
No situation data available.
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 |
---|---|---|---|
Nephtys hystricis | 43 | 41-60% | |
Amphiura chiajei | 23 | 41-60% | |
Chaetozone setosa | 21 | 41-60% | |
Nephrops norvegicus | 20 | Frequent | 61-80% |
Virgularia mirabilis | 17 | Frequent | 61-80% |
Cerianthus lloydii | 10 | Occasional | 61-80% |
Abra alba | 7 | 21-40% | |
Asterias rubens | 7 | Occasional | 41-60% |
Liocarcinus depurator | 6 | Occasional | 41-60% |
Pennatula phosphorea | 6 | Frequent | 41-60% |
Pagurus bernhardus | 5 | Occasional | 41-60% |
Amphiura chiajei | 3 | Common | 21-40% |
Amphiura filiformis | 3 | Common | 21-40% |
Kurtiella bidentata | 3 | 21-40% | |
Seraphsidae | 2 | Occasional | 21-40% |
Turritellinella tricarinata | 2 | Frequent | 21-40% |
Funiculina quadrangularis | 2 | Frequent | 21-40% |
Munida rugosa | 1 | Occasional | 21-40% |
Similar biotopes or habitat types
Not applicable or unknown.
Classification history of this biotope or habitat type
Classification version | Code | Habitat name |
---|---|---|
2015 (15.03) | SS.SMu.CFiMu | Circalittoral fine mud |
2004 (04.05) | SS.SMu.CFiMu | Circalittoral fine mud |
1997 (97.06) | SS.CMU | Circalittoral muddy sands |