MarLIN

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

A red seaweed (Chondria coerulescens)

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

Summary

Description

Chondria coerulescens has bluish or yellowish fronds with blue iridescence. The fronds are flexible and cartilaginous in texture, turning black when dry. Young axes show a striking turquoise iridescence when alive. The thalli consist of cylindrical erect axes or trailing tufts, and is 3-8 cm high when erect. The distinct main axis is 0.4-0.5 mm in diameter, branching sparsely at irregular intervals in a spiral pattern to 1-3 orders of branching. Branches are linear, often long and curve downwards gradually tapering to a slender point, and reattach by secondary holdfast. The morphology shows relatively little variation except that some thalli consist only of inconspicuous isolated erect axes whereas others form dense tufts.

Recorded distribution in Britain and Ireland

Recorded from the Salcombe Estuary, The Isle of Wight, Milford Haven, Exmouth and Portsmouth.

Global distribution

England to Morocco; Mediterranean

Habitat

Chondria coerulescens is a subtidal species, growing on pebbles in mud from extreme low water to 4 m depth. It inhabits extremely wave sheltered sites, usually in inlets with moderate to strong current exposure.

Depth range

-

Identifying features

  • Small species, up to 8 cm high.
  • Branched cylindrical axes.
  • Distinctive bright blue iridescence.
  • Sparsely branched at irregular intervals in a spiral pattern.

Additional information

Chondria coerulescens may be confused with Laurencia obtusa. Microscope examination of the periaxial (surrounding the axis) cells would be needed to separate them. Although Chondria coerulescens is nationally rare, it can be abundant in favourable habitats.

Listed by

- none -

Further information sources

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Bibliography

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

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

  3. JNCC (Joint Nature Conservation Committee), 1999. Marine Environment Resource Mapping And Information Database (MERMAID): Marine Nature Conservation Review Survey Database. [on-line] http://www.jncc.gov.uk/mermaid

  4. 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.

  5. National Biodiversity Network (NBN) Atlas website. Available from: http://www.nbnatlas.org.  Accessed 01 April 2017

  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., http://www.itsligo.ie/biomar/

Citation

This review can be cited as:

Edwards, R.V. 2005. Chondria coerulescens 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. Available from: http://www.marlin.ac.uk/species/detail/1933

Last Updated: 04/07/2005