From sea level to approximately 10,000 feet in elevation, typically on rocky surfaces or bark
Native to North America, including northern California and the Washoe County area
Vulnerable to critically impaired
This species is
to the Truckee Meadows.
Stonewall rim is a type of common lichen. Lichens are complex organisms that arise from symbiotic relationships between fungi and a photosynthesizer, like algae. This crustose lichen will strongly adhere to a surface, like rock or bark, and form a crust-like (crustose) layer that is very difficult to separate from the surface without destroying the lichen itself. Stonewall rim tends to grow in “rosettes,” which is a circular arrangement of leaves that share a center point, and can grow all over the world. This lichen generally appears pale whitish to greenish yellow, has a shiny or waxy surface, and looks to be made up of tiny disc-like fruiting bodies called “apothecia.” Most of the colored bodies will be towards the center with the paler whites towards the edges.
“Lecanora Muralis” is no longer the active taxon for this lichen but can be used for previously existing research. The current scientific name is Protoparmeliopsis Muralis.
Stonewall rim is commonly misidentified as numerous other lichen, including, but not limited to: golden moonglow lichen; rock greenshield lichen; and sagebrush rim lichen. Take your camera and compare your photos!
Rock lichens generally are considered inedible because they are so difficult to digest. However, they are vitally important contributors for future plants as they help break down rocks via acid secretion and therefore increasing soil fertility.
Some lichens are believed to contain medicinal qualities -- the Japanese view certain lichens as possible cancer-fighting agents.
Here in the Truckee Meadows, stonewall rim has been seen in Mayberry Park and Hidden Valley Regional Park.
iNaturalist, Lecanora Muralis, April 2021, https://www.inaturalist.org/taxa/154082-Lecanora-muralis
iNaturalist, Protoparmeliopsis Muralis, April 2021, https://www.inaturalist.org/taxa/632126-Protoparmeliopsis-muralis
Earth Research Institute, Stonewall Rim Lichen, April 2021, https://annual-reports.eri.ucsb.edu/2012-2013/stonewall-rim-lichen
National Park Service, Lichens, April 2021, https://www.nps.gov/grte/learn/nature/lichen.htm#:~:text=Lichens%20play%20a%20unique%20role,and%20slowly%20create%20new%20soil.&text=The%20fungus%20builds%20the%20body,and%20nutrients%20for%20both%20organisms.
Los Angeles Times, Wild About Lichens, April 2021, https://www.latimes.com/archives/la-xpm-2002-jan-14-sci-lichen14-story.html#:~:text=People%20don't%20generally%20eat,they%20are%20difficult%20to%20digest.&text=Lichens%20also%20play%20a%20crucial,increase%20the%20fertility%20of%20soil.
Image: Jason Hollinger, https://www.flickr.com/photos/7147684@N03/2972517910/, license https://creativecommons.org/licenses/by/2.0/, cropped from original.
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