Leprocaulon beechingii (Leprocaulaceae), a new species from the southern Appalachian Mountains of eastern North America

Leprocaulon beechingii is described as new to science based on collections from exposed rock outcrops in the southern Appalachian Mountains in eastern North America. Taxonomic placement in Leprocaulon, and delimitation from other members of the genus with usnic acid, is supported by molecular phylogenetic analyses of ITS and mtSSU sequence data. The species is readily recognized by its occurrence on non-calcareous rocks, normandinoides-type placodioid thallus, and the production of usnic acid and zeorin.