Overview

Brief Summary

Description

 Life habit: lichenized, not lichenicolous; Thallus: crustose, composed of scattered areoles or areolate to rimose; prothallus: black, poorly to well developed; areoles: round to angular, plane to strongly convex, up to 1.4 mm in diam.; surface: greenish yellow or bright yellow, epruinose, smooth; medulla: KI+ deeply blue; Apothecia: round or angular, up to 1 mm in diam.; disc: black, plane or weakly convex, epruinose; exciple: pale brown to brownish red; epihymenium: brown or reddish brown, K+ red, not containing crystals; hymenium: hyaline or more rarely green, 100-180 µm tall; paraphyses: clavate, with hyaline tips; hypothecium: dark brown, K-; asci: clavate, 8-spored; ascospores: hyaline to pale green-brown initially, becoming dark green to brown, submuriform or muriform, ellipsoid, 20-36 x 10-20 µm, halonate; Spot tests: medulla K-, C- or rarely C+ red, P+ yellow; Secondary metabolites: rhizocarpic and psoromic acids, and rarely gyrophoric acid.; Substrate and ecology: on non-calciferous rock in open sites, mainly in coniferous regions, at 1000-3720 m alt., uncommon; World distribution: cosmopolitan; Sonoran distribution: Arizona, southern California, and Baja California, most frequently above 1500; Notes: The present circumscription is based on the frequent correlation of psoromic acid in the medulla with a hyaline hymenium and with average spore length being less than 34 µm. Specimens having psoromic acid and average spore length larger than 34 µm usually have a green hymenium, and are here referred to R. macrosporum. Specimens lacking psoromic acid usually have somewhat longer spores than R. geographicum and a green hymenium; these are here referred to R. riparium. There are no apparent macroscopic differences between the three species in the Sonoran material, and some specimens show intermediate combinations of the above features. This circumscription of R. geographicum conforms more or less with Runemark's (1956a) circumscription of R. tinei and R. lindsayanum ssp. kittilense, but Runemark placed more importance on the K-reaction of the epihymenium, and less importance on the secondary chemistry. 
Creative Commons Attribution Non Commercial Share Alike 3.0 (CC BY-NC-SA 3.0)

© Lichen Unlimited: Arizona State University, Tempe.

Source: Lichen Flora of the Greater Sonoran Desert Region

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Comprehensive Description

General Description

Common Name: Golden Map Lichen

 

Bright lemon-yellow to greenish-yellow tiled crustose lichen growing over a thin unlichenized black prothallus on exposed granite and other siliceous rocks, especially in mountains.

Creative Commons Attribution Non Commercial Share Alike 3.0 (CC BY-NC-SA 3.0)

© Jason Hollinger

Source: Mushroom Observer

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Distribution

National Distribution

Canada

Origin: Native

Regularity: Regularly occurring

Currently: Present

Confidence: Confident

United States

Origin: Unknown/Undetermined

Regularity: Regularly occurring

Currently: Unknown/Undetermined

Confidence: Confident

Creative Commons Attribution Non Commercial 3.0 (CC BY-NC 3.0)

© NatureServe

Source: NatureServe

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Cosmopolitan.

Creative Commons Attribution Non Commercial Share Alike 3.0 (CC BY-NC-SA 3.0)

© Jason Hollinger

Source: Mushroom Observer

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Physical Description

Diagnostic Description

THALLUS: pale to bright lemon yellow to greenish-yellow, areolate crust, underlain by thin black prothallus visible around the margins and between areolae
 APOTHECIA: black inset discose apothecia, often angular like areoles
 SPORES: brown, muriform, 20-36 × 10-20 µm
 CHEMISTRY: cortex UV+y (rhizocarpic acid major), medulla PD+ yellow (psoromic acid major), rarely C+ fleeting pink/red (gyrophoric acid in cortex? or medulla?)

Creative Commons Attribution Non Commercial Share Alike 3.0 (CC BY-NC-SA 3.0)

© Jason Hollinger

Source: Mushroom Observer

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Look Alikes

There are severa other yellow Rhizocarpon species:

                          
R. macrosporum identical except for spore size (32-60 × 15-22 µm), less common
R. lecanorinum also has brown muriform spores, crescent-shaped areoles around some apothecia, epihymenium K- or K+ green instead of K+ violet or purple
others spores 2-celled and medulla K/I- in section (instead of blue)
 

Some other genera that have yellow-and-black crustose thalli:

                                          
Acarospora apothecia brownish to yellowish, many spores per ascus, areoles often round or subsquamulose, rarely angular, no black prothallus
Pleopsidium apothecia brownish to yellowish, areoles elongate into distinct short lobes at margin, no prothallus
Dimelaena oreina very pale, distinctly radiating lobes at margin, apothecia not black
Caloplaca yellow to orange, pigment K+ wine red, apothecia not black (in orange species)
Candelina apothecia orange, distinctly lobate around margin, no prothallus
Creative Commons Attribution Non Commercial Share Alike 3.0 (CC BY-NC-SA 3.0)

© Jason Hollinger

Source: Mushroom Observer

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Ecology

Habitat

Sunny, exposed, non-calcareous rocks, generally in mountains (1000-3720 m).

Creative Commons Attribution Non Commercial Share Alike 3.0 (CC BY-NC-SA 3.0)

© Jason Hollinger

Source: Mushroom Observer

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Conservation

Conservation Status

National NatureServe Conservation Status

Canada

Rounded National Status Rank: N5 - Secure

United States

Rounded National Status Rank: NNR - Unranked

Creative Commons Attribution Non Commercial 3.0 (CC BY-NC 3.0)

© NatureServe

Source: NatureServe

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

NatureServe Conservation Status

Rounded Global Status Rank: G5 - Secure

Reasons: This lichen occurs throughout most of Canada and the western U.S., excluding the interior basin, and in the southern Appalachians and New England. This species typically grows in exposed arctic and alpine habitats on siliceous rocks.

Creative Commons Attribution Non Commercial 3.0 (CC BY-NC 3.0)

© NatureServe

Source: NatureServe

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Relevance to Humans and Ecosystems

Benefits

Uses

Commonly used in lichenometry to date exposed rock surfaces.

Creative Commons Attribution Non Commercial Share Alike 3.0 (CC BY-NC-SA 3.0)

© Jason Hollinger

Source: Mushroom Observer

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Wikipedia

Map lichen


Rhizocarpon geographicum (the map lichen) 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 is a lichen widely used by climatologists in determining the relative age of deposits, e.g. moraine systems, thus revealing evidence of glacial advances. The process is termed lichenometry.

Lichenometry is based on the assumption that the largest lichen growing on a rock is the oldest individual. If the growth rate is known, the maximum lichen size will give a minimum age for when this rock was deposited.

Growth rates for different areas and species can be obtained by measuring maximum lichen sizes on substrates of known age, such as gravestones, historic or prehistoric rock buildings, or moraines of known age (e.g. those deposited during the Little Ice Age).

Distribution[edit]

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[1] and northern Boreal forests of Canada, Greenland, Iceland Fennoscandia and Siberia.[2] 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[citation needed], in the Falkland Islands, the sub Antarctic islands and the Antarctic Peninsula.[3]

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. [4]

Map lichen Kerry.jpg

Outer space[edit]

In an experiment, this lichen species was placed in a capsule and launched into space. The capsule was opened, exposing the lichen to space conditions for 10 days before being brought back down to Earth, where it showed minimal changes or damage.[5]

Further information: BIOPAN and EXPOSE


See also[edit]

References[edit]

  1. ^ Tracy Irwin Storer, Robert Leslie Usinger and David Lukas. 2004. Sierra Nevada Natural History, 2nd ed, University of California Press, ISBN 0-520-24096-0, ISBN 978-0-520-24096-4, 439 pages
  2. ^ C. Michael Hogan. (2008) Black Spruce: Picea mariana, GlobalTwitcher.com, ed. Nicklas Stromberg
  3. ^ Global Biodiversity Information Facility
  4. ^ Frank Dobson. 1979. Lichens, An Illustrated Guide The Richmond Publishing Co Ltd, ISBN 0-85546-203-5, page 244
  5. ^ de la Torre, Rosa; Leopoldo G. Sancho, Gerda Horneck, Asunción de los Ríos, Jacek Wierzchos, Karen Olsson-Francis, Charles S. Cockell, Petra Rettberg, Thomas Berger, Jean-Pierre P. de Vera (August 2010). "Survival of lichens and bacteria exposed to outer space conditions – Results of the Lithopanspermia experiments". Icarus 208 (2): 735–748. doi:10.1016/j.icarus.2010.03.010. ISSN 0019-1035. 
Creative Commons Attribution Share Alike 3.0 (CC BY-SA 3.0)

Source: Wikipedia

Unreviewed

Article rating from 0 people

Default rating: 2.5 of 5

Disclaimer

EOL content is automatically assembled from many different content providers. As a result, from time to time you may find pages on EOL that are confusing.

To request an improvement, please leave a comment on the page. Thank you!