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Marine Habitat Classification

Description of biotope or habitat type

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   Acanella arbuscula assemblage on Atlantic mid bathyal mud

Physical habitat description

Salinity Full (30-35 ppt)
Wave exposure
Tidal streams
Substratum Mud - sandy silts and fine grained oozes
Zone Atlantic mid bathyal
Depth Band Biotope depth range 600 - 1300 m (based on zone); assemblage recorded from 900 - 1200 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 M.AtMB.Mu.EreCor.AcaArb <i>Acanella arbuscula</i> assemblage on Atlantic mid bathyal 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.


This biotope is composed of dense aggregations of the Isidid octocoral Acanella arbuscula on sandy silts and fine grained oozes. It is likely to be functionally similar to a seapen field. Gage (1986) describes growths of the arborescent gorgonian Acanella arbuscula as providing a “perch” for such fauna as the brittle star Ophiacantha bidentata to feed in the current. This assemblage was also recorded in the lower bathyal but associated species are likely to differ with depth. Characterising species listed refer to all Acanella arbuscula assemblages not just those found associated with the zone and substrate specified in this biotope. This assemblage is described from published literature only.


No situation data available.

Temporal variation

No temporal variation data available.

Characterising species

Taxon % of core records where taxon was recorded
Acanella arbuscula
Ophiacantha bidentata
Hymenaster pellucidus
Dytaster grandis grandis
Porcellanaster ceruleus
Echinosigra phiale
Ypsilothuria bitentaculata attenuate
Peniagone azorica
Ophiomusa lymani
Phelliactis robusta
Flabellum (Ulocyathus) alabastrum

Similar biotopes or habitat types

The same epifaunal assemblage in the lower bathyal. Associated infauna are likely to differ.

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