A distinctive species with a white or pale grey thallus and a dark prothallus. The black, stellate apothecia tend to be numerous.
In Scotland, Arthonia radiata is widespread on smooth-barked trees in unpolluted areas. BLS distribution map
Arthonia radiata is often found alongside Lecidella elaeochroma and Lecanora chlarotera in a pioneer community on deciduous trees.
scottishlichens.co.uk 