A crustose species with a distinctive yellow-orange to yellow-grey crust that is cracked to areolate. The surface of the thallus is uneven with low warts from which the apothecia arise. The discs are black but frequently covered in a grey to orange pruina. When mature, the discs become umbonate and the margins flexuose.
Thallus: C-, K-
Porpidia flavocruenta is local in upland Scotland where it prefers shaded and damp, siliceous rock. BLS distribution map
Porpidia flavocruenta is distinguished from Porpidia melinodes on basis of the lack of soredia.
scottishlichens.co.uk 