Xanthoria parietina is a foliose, or leafy, lichen. It has wide distribution, and many common names such as common orange lichen, yellow scale, maritime sunburst lichen and shore lichen. It can be found near the shore on rocks or walls (hence the epithet parietina meaning "on walls"), and also on inland rocks, walls, or tree bark. It was chosen as a model organism for genomic sequencing (planned in 2006) by the US Department of Energy Joint Genome Institute (JGI). In the past it was used as a remedy for jaundice because of its yellow colo
Habitat and distribution Hardwood forests in low-elevation broad valleys; scattered on Populus and other hardwoods in riparian areas in agricultural and populated areas] It is often associated with high level of nitrogen and favored by eutrophication. and can be often found near farmland and around livestock. X. parietina is a widespread lichen, and has been reported from Australia, Africa, Asia, North America and throughout much of Europe. In eastern North America and Europe, it is found more frequently near coastal locations. The increases in NO3 deposition as a result of industrial and agricultural developments in southern Ontario, Canada in the 20th century are thought to be responsible for the reappearance of this species in the local lichen flora.
Xanthoria parietina is a very pollution-tolerant species. In laboratory experiments, this species can tolerate exposure to air contaminants and bisulphite ions with little or no damaging effect. It is also tolerant of heavy metal contamination. For these reasons, this species has found use as a biomonitor for measuring levels of toxic elements