Description of biotope or habitat type
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Infralittoral fine mud
Physical habitat description
| Salinity | Full (30-35 ppt), Variable (18-35 ppt) |
|---|---|
| Wave exposure | Sheltered, Very sheltered, Extremely sheltered |
| Tidal streams | Weak (>1 kn), Very weak (negligible) |
| Substratum | Mud (occasionally with shells or stones) |
| Zone | Infralittoral |
| Depth Band | 0-5 m, 5-10 m, 10-20 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
Shallow sublittoral muds, extending from the extreme lower shore to about 15-20 m depth in fully marine or near marine conditions, predominantly in extremely sheltered areas with very weak tidal currents. Such habitats are found in sea lochs and some rias and harbours. Populations of the lugworm Arenicola marina may be dense, with anemones, the opisthobranch Philine aperta and synaptid holothurians also characteristic in some areas. The extent of the oxidised layer may be shallow with some areas being periodically or permanently anoxic. In these areas bacterial mats may develop on the sediment surface. Infaunal records for this biotope complex are limited encompassing only one biotope. They are therefore not representative of the full suite of infaunal species found in this biotope.
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 |
|---|---|---|---|
| Cerastoderma edule | 33 | Common | 81-100% |
| Carcinus maenas | 25 | Occasional | 61-80% |
| Abra nitida | 22 | Common | 61-80% |
| Peringia ulvae | 20 | Frequent | 61-80% |
| Beggiatoa | 16 | 21-40% | |
| Chaetozone caputesocis | 15 | Frequent | 61-80% |
| Arenicola marina | 12 | Frequent | 41-60% |
| Pagurus bernhardus | 7 | Occasional | 41-60% |
| Asterias rubens | 6 | Occasional | 41-60% |
| Philine aperta | 6 | Frequent | 21-40% |
| Diatoms - film | 4 | 21-40% | |
| Aphelochaeta marioni | 4 | 41-60% | |
| Oxydromus flexuosus | 4 | 41-60% | |
| Liocarcinus depurator | 3 | Rare | 21-40% |
| Cerianthus lloydii | 2 | Occasional | 21-40% |
| Hediste diversicolor | 2 | Frequent | 21-40% |
| Hydractinia echinata | 2 | Occasional | 21-40% |
| Saccharina latissima | 2 | 21-40% | |
| Polydora ciliata | 1 | 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.IFiMu | Infralittoral fine mud |
| 2004 (04.05) | SS.SMu.IFiMu | Infralittoral fine mud |
| 1997 (97.06) | SS.IMU.MarMu | Shallow marine mud communities |