Biodiversity & Conservation

A red seaweed - Furcellaria lumbricalis

Furcellaria lumbricalis

Image Keith Hiscock - The seaweed Furcellaria lumbricalis, plant with fertile branches. Image width ca 15 cm.
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Distribution map

Furcellaria lumbricalis recorded (dark blue bullet) and expected (light blue bullet) distribution in Britain and Ireland (see below)

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Furcellaria lumbricalis is not listed under any importance categories.

Taxonomy icon Taxonomy Taxon English term
Phylum Rhodophyta Red seaweeds
Class Florideophyceae
Authority (Hudson) J.V. Lamouroux (1813)
Recent synonyms Furcellaria fastigiata, Fucus fastigiata
Map icon Recorded Distribution in Britain and Ireland Occurs around all coasts of Britain and Ireland. There is a paucity of records from eastern England and the east coast of Ireland which may reflect a lack of suitable substrata.
Habitat information icon Habitat information Furcellaria lumbricalis typically grows on rock and stones in the shallow subtidal to a depth of 20 m on sheltered to moderately exposed coasts. Although Furcellaria lumbricalis has been recorded in depths up to 30 m or more in clear water it is rarely found that deeply, especially around the UK, and one would expect to find it to depths of around 10 m. It also occurs in rockpools in the eulittoral. The holdfast is often covered by coarse, sandy deposits. Tolerates sand cover.
Text page icon Description A reddish brown to brownish black seaweed with glossy, cartilaginous, cylindrical fronds, branching dichotomously 6 to 11 times. The fronds rise from a much branched holdfast up to 25 mm in diameter. The reproductive bodies occur as pod-like structures at the ends of the branches. The seaweed grows up to about 30 cm in length.
Identifying features
  • Erect, cylindrical, dichotomously branching fronds.
  • Holdfast is a mass of rhizoids.
  • Reddish brown to brownish black in colour, brown in transmitted light and sometimes bleached green by sunlight.
  • Tetrasporangial plants larger than gametangial, with branches terminating in spindle shaped pod-like structures.
  • Female thalli with fructifications similar to tetrasporangia but with attenuate sterile tip, often forked and 8-18mm long.
  • Male thalli distinctive as fertile tips of branches are ovoid, ca 5mm long, slimy and yellowish in colour tinged with pink.
Additional information icon Additional information

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This review can be cited as follows:

Will Rayment 2008. Furcellaria lumbricalis. A red seaweed. Marine Life Information Network: Biology and Sensitivity Key Information Sub-programme [on-line]. Plymouth: Marine Biological Association of the United Kingdom. [cited 09/02/2010]. Available from: <http://www.marlin.ac.uk/speciesinformation.php?speciesID=3356>