Biodiversity & Conservation

A red seaweed - Phycodrys rubens

Phycodrys rubens

Image Keith Hiscock - Phycodrys rubens on a kelp stipe at 10 m depth. Image width ca 22 cm.
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Distribution map

Phycodrys rubens recorded (dark blue bullet) and expected (light blue bullet) distribution in Britain and Ireland (see below)

Why do the maps differ?

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Phycodrys rubens is not listed under any importance categories.

Taxonomy icon Taxonomy Taxon English term
Phylum Rhodophyta Red seaweeds
Class Florideophyceae
Authority (Linnaeus) Batters, 1902
Recent synonyms None
Map icon Recorded Distribution in Britain and Ireland Commonly sublittoral present on rocky substrata in northern Britain but more widely distributed on kelp stipes. Absent from parts of the east coast where turbid waters and a lack of suitable substrata preclude its growth.
Habitat information icon Habitat information It is common in lower shore rock pools and the subtidal, growing on both rock and on the stipes of Laminaria hyperborea to a depth of up to 30 m.
Text page icon Description A small red alga, up to 15 cm tall, with a leaf-like frond, with midrib, lateral veins and serrated margin that give the impression of an oak leaf. The disc-like holdfast gives rise to a short toughened stipe. In winter the frond wears away due to a combination of cessation of growth and wave action, leaving just the mid-rib, the blade growing back in spring. Phycodrys rubens is light crimson in colour and can be distinguished from the similarly leaf-like Delesseria sanguinea by the deeply serrated frond and branching habit.
Identifying features
  • Up to 15 cm tall.
  • Leaf-like frond suggestive of an oak leaf and deeply serrated.
  • Disc-like holdfast.
  • Light crimson in colour.
  • Fronds have a branching habit.
Additional information icon Additional information No text entered

This review can be cited as follows:

Paolo Pizzolla 2007. Phycodrys rubens. 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=4114>