A distinctive species that forms placodioid, circular patches that consist of greenish grey to yellow-grey, adpressed lobes which are often pruinose or pearly coloured around the edges. The apothecia, usually confined to the centre of the thallus, have a creamy brown to brown disc and margins that often become crenulate when mature.
Thallus: C-, K, UV+ dull orange
In Scotland, Lecanora muralis is found mainly in the east and other lowland areas where it grows on nutrient-enriched bird-perches rocks and manmade substrata, including gravestones. BLS distribution map
scottishlichens.co.uk 