information on the biology of species and the ecology of habitats found around the coasts and seas of the British Isles

A sea slug (Polycera faeroensis)

Distribution data supplied by the Ocean Biogeographic Information System (OBIS). To interrogate UK data visit the NBN Atlas.



Polycera faeroensis has a slightly swollen, white translucent body up to 5 cm in length. The body may, but rarely posses round yellow spots. There are at least 8 yellow tipped oral veil processes, with a yellow tipped process either side of the gills which; in larger individuals, become flattened developing several larger points. Yellow pigmentation is also present in the tips of the rhinophores, propodial tentacles (anterior section of foot), oral lobes and gills.

Recorded distribution in Britain and Ireland

This species is commonly found on the west and south west coasts of Scotland, Wales, England and Ireland. It has also been recorded on the north east coast of Scotland and Ireland.

Global distribution



Polycera faeroensis can commonly be found feeding on erect bryozoans Crisia and Bugula sp. in shallow water on steep rock faces.

Depth range


Identifying features

  • Up to 5 cm in length.
  • White translucent body.
  • At least 8 yellow tipped frontal processes on the oral veil.

Additional information

This species lays a white coiled ribbon spawn. It may be confused with Polycera quadrilineata, which has slightly darker yellow pigments and usually fewer frontal processes. Both Polycera faeroensis and Polycera quadrilineata can be found feeding on Membranipora membranacea (sea-mat) in the same location.

Listed by

- none -

Further information sources

Search on:


  1. Howson, C.M. & Picton, B.E., 1997. The species directory of the marine fauna and flora of the British Isles and surrounding seas. Belfast: Ulster Museum. [Ulster Museum publication, no. 276.]

  2. JNCC (Joint Nature Conservation Committee), 1999. Marine Environment Resource Mapping And Information Database (MERMAID): Marine Nature Conservation Review Survey Database. [on-line]

  3. National Biodiversity Network (NBN) Atlas website. Available from:  Accessed 01 April 2017

  4. Naylor, P., 2000. Marine Animals of the South West. Plymouth: Sound Diving Publications

  5. Picton, B. E. & Morrow, C.C., 1994. A Field Guide to the Nudibranchs of the British Isles. London: Immel Publishing Ltd.

  6. Picton, B.E. & Costello, M.J., 1998. BioMar biotope viewer: a guide to marine habitats, fauna and flora of Britain and Ireland. [CD-ROM] Environmental Sciences Unit, Trinity College, Dublin.,

  7. Thompson, T.E. & Brown, G.H., 1984. Biology of Opisthobranch Molluscs, vol. II. London: Ray Society.


This review can be cited as:

Rowley, S.J. 2008. Polycera faeroensis A sea slug. In Tyler-Walters H. and Hiscock K. (eds) Marine Life Information Network: Biology and Sensitivity Key Information Reviews, [on-line]. Plymouth: Marine Biological Association of the United Kingdom. [cited 25-02-2018]. Available from:

Last Updated: 24/04/2008