A crustose species with a creamy white, granular or areolate thallus that may be surrounded by a pale brown prothallus. The small, sessile apothecia have dark green, red-brown to black discs. The thalline margin often become excluded with age.
Thallus: C-, K-, UV+ pale orange
In Scotland, Lecanora aitema has a scattered distribution in upland areas where it grows on acidic bark and twigs, wood and worked timber like fenceposts. BLS distribution map
scottishlichens.co.uk 