Rhizocarpon geographicum

Rhizocarpon geographicum

"Rhizocarpon geographicum" is a species of lichen, which grows on rocks in mountainous areas of low air pollution. Each lichen is a flat patch bordered by a black line of spores. These patches grow adjacent to each other, leading to the appearance of a map or a patchwork field.
Map Lichen Lichens of the mountains include the Map Lichen (Rhizocarpon geographicum) Cadillac Mountain • Acadia National Park, Maine, United States. Acadia National Park,Cadillac Mountain,Geotagged,Maine,Map Lichen,Rhizocarpon geographicum,Summer,United States

Distribution

This lichen species is broadly distributed and may be found in most cold areas with exposed rock surfaces. The North American range includes the Sierra Nevada and northern Boreal forests of Canada, Greenland, Iceland, Fennoscandia and Siberia. In the tropics it only occurs at high altitudes such as the Andes of Peru and Colombia. Further south the Map lichen is found broadly across Patagonia, in the Falkland Islands, the sub Antarctic islands and the Antarctic Peninsula.

In Britain it can be found commonly growing on hard siliceous rocks, especially in upland regions. Its range covers virtually all of Scotland, much of North West England, and other upland areas in much of the rest of England, Wales and Ireland too.

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Taxonomy
KingdomFungi
DivisionAscomycota
ClassLecanoromycetes
OrderLecanorales
FamilyRhizocarpaceae
GenusRhizocarpon
SpeciesR. geographicum