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

A red seaweed (Plumaria plumosa)

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



Plumaria plumosa is a dull red to brownish-purple seaweed, 5-10 cm long, it is soft and flaccid and has many branches which become tatty in older plants. This perennial plant is monosiphonous throughout and its fronds branch irregularly from the base in one plane. The thallus is compressed, and the branches are all delicately plumose.

Recorded distribution in Britain and Ireland

Common throughout the British Isles, with only a limited distribution in the southeast of England and absent from the northeast of Ireland.

Global distribution



Grows on shaded areas of the lower littoral rocky shore, particularly on vertical rocks and overhangs.

Depth range


Identifying features

  • Delicate plumose branches.
  • Thallus is compressed.
  • Fronds branch irregularly from the base, in one plane.

Additional information

Plumaria plumosa is frequently confused with Ptilota plumosa . However, Plumaria plumosa can be identified by the penultimate branchlets which lack an outer covering (uncorticated) and are translucent, with the main axes having a spongy mat surface. Plumaria plumosa reproduces in the south of England during winter, and is fertile in spring and summer in more northerly latitudes.

Listed by

- none -

Further information sources

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

  2. Fish, J.D. & Fish, S., 1996. A student's guide to the seashore. Cambridge: Cambridge University Press.

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

  4. 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.]

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

  6. Maggs, C.A. & Hommersand, M.H., 1993. Seaweeds of the British Isles: Volume 1 Rhodophycota Part 3A Ceramiales. London: Natural History Museum, Her Majesty's Stationary Office.

  7. McLeod, C.R., Yeo, M., Brown, A.E., Burn, A.J., Hopkins, J.J. & Way, S.F. (ed.), 2002. The Habitats Directive: selection of Special Areas of Conservation in the UK. 2nd edn., 2002-10-04

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


This review can be cited as:

Edwards, R.V. 2003. Plumaria plumosa A red seaweed. 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 22-09-2018]. Available from:

Last Updated: 29/08/2003