Common Orange Lichen

Common Orange Lichen, scientifically Xanthoria parietina and also known as the yellow wall lichen or maritime sunburst lichen, is a common and widespread lichen-forming fungus in the family Teloschistaceae, first described by Carl Linnaeus in 1753. Its leafy, overlapping lobes typically measure less than 8 centimeters across and range from bright orange in sun-exposed locations to greenish-yellow in shaded environments, and unlike many lichens it tolerates pollution and excess nitrogen well, growing on coastal rocks, urban walls and tree bark; it has become one of the most thoroughly studied lichens in the science of lichen biology.