Cetrelia monachorum

Cetrelia monachorum is a species of foliose lichen in the family Parmeliaceae. It was first described scientifically in 1930 by Alexander Zahlbruckner as a species of Parmelia. Husband and wife lichenologists William and Chicita Culberson transferred it into the genus Cetrelia in 1977. It is found in Asia, Europe, and North America.