Cinder Lichen

Cinder lichen (Aspicilia cinerea) is a crustose lichen in the family Megasporaceae, found widely across the Northern Hemisphere in boreal, montane, and arctic regions of Europe, Asia, and North America. It grows as a flat, gray to ash-gray crust on exposed siliceous rock surfaces—particularly granite, gneiss, and other hard acidic rocks—in open, high-light environments such as moorland boulders, mountain crags, stream-side rocks, and coastal outcrops. The cinder lichen's granular to warty thallus and its pale gray color, reminiscent of volcanic ash or cinder, give the species its common name. Aspicilia cinerea is classified as Least Concern, with widespread and abundant populations in suitable rocky habitats. Like many saxicolous lichens, it is extremely slow-growing and may live for centuries on stable rock surfaces. The species forms part of diverse epilithic lichen communities that colonize bare rock and contribute to biological weathering and soil formation. It is resistant to desiccation and temperature extremes, making it well adapted to exposed subalpine and arctic environments. Cinder lichen has been used as a model organism in studies of lichen growth rates and rock weathering. The genus Aspicilia is one of the largest in lichenized fungi, and molecular work has substantially revised its circumscription.