Biodiversity & Conservation

Orange sea lichen - Caloplaca marina


Caloplaca marina

Image Harvey Tyler-Walters - Caloplaca marina. Image width ca 15 cm.
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Distribution map

Caloplaca marina 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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Caloplaca marina is not listed under any importance categories.


Taxonomy icon Taxonomy Taxon English term
Phylum Ascomycota Sac fungi
Class Lecanoromycetes
Authority (Weddell) Zahibruckner, 1921
Recent synonyms None
Map icon Recorded Distribution in Britain and Ireland Widely distributed around the British Isles. Gaps in its recorded distribution probably due to lack of suitable substrata.
Habitat information icon Habitat information A strictly maritime species, common on hard rocks and concrete from just above high water level.
Text page icon Description An encrusting yellow-orange to bright orange lichen. The thallus is composed of small granules or 'islands' of tissue but is never powdery. When well developed the crust may be composed of small convex islands of tissue often with a paler edge. Disc-like, convex and deep reddish orange fruiting bodies occur on the surface of the thallus.
Identifying features
  • Thallus granular, orange to orange red in colour but never powdery.
  • Fruiting bodies disc-like, convex and deep reddish orange.
  • Marginal lobes not clearly defined.
  • Strictly maritime at or above high water.
Additional information icon Additional information Caloplaca marina is one of several species of Caloplaca found on rocks at or above high water. Caloplaca thallincola may occur at the same position but prefers sheltered conditions. Caloplaca thallincola is a lighter orange with a distinct lobose margin. Caloplaca maritima is also similar but is never orange and the thallus is composed of more convex, paler, wax-like islands of tissue. Identification to genus or species level may require simple chemical tests; for details see Dobson (2000).

This review can be cited as follows:

Dr Harvey Tyler-Walters 2002. Caloplaca marina. Orange sea lichen. Marine Life Information Network: Biology and Sensitivity Key Information Sub-programme [on-line]. Plymouth: Marine Biological Association of the United Kingdom. [cited 03/09/2010]. Available from: <http://www.marlin.ac.uk/speciesinformation.php?speciesID=2863>