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

Red rags (Dilsea carnosa)

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



One of the larger red seaweeds, Dilsea carnosa plants are tough and leathery. Several dark reddish brown, flat, blades gradually expand from a single disc shaped holdfast, and have short cylindrical stipes. The blades do not have a midrib or veins and are simple wedge or spoon shaped. The blades can be 15-30 cm long and 5-20 cm wide. Older blades may be split from the margin towards the base but the rounded oblong (obovate) shape of the blade is never quite lost.

Recorded distribution in Britain and Ireland

Widespread in the British Isles but more abundant in the south of England.

Global distribution

Arctic Russia to Portugal.


Usually found in the lower littoral to shallow sublittoral attached to rocks.

Depth range


Identifying features

  • Large leathery dark red blades.
  • Rounded oblong or spoon shape blades, split when older.
  • Blades without midrib and gradually expanding from a short cylindrical stipe.

Additional information

Sometimes confused with Palmaria palmata and mistakenly called dulse.

Listed by

- none -

Further information sources

Search on:


  1. Dickinson, C.I., 1963. British seaweeds. London & Frome: Butler & Tanner Ltd.

  2. Hardy, F.G. & Guiry, M.D., 2003. A check-list and atlas of the seaweeds of Britain and Ireland. London: British Phycological Society

  3. Hayward, P., Nelson-Smith, T. & Shields, C. 1996. Collins pocket guide. Sea shore of Britain and northern Europe. London: HarperCollins.

  4. Hiscock, S., 1986b. A field key to the British Red Seaweeds. Taunton: Field Studies Council. [Occasional Publication No.13]

  5. 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.]

  6. Irvine, L.M., 1983. Seaweeds of the British Isles vol. 1. Rhodophyta Part 2A. Cryptonemiales (sensu stricto), Palmariales, Rhodymeniales. London: British Museum (Natural History).

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

  8. 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.


This review can be cited as:

Neish, A.H. 2003. Dilsea carnosa Red rags. 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 25-09-2018]. Available from:

Last Updated: 01/07/2003