Description: Thallus crustose, forming more or less orbicular patches, very thin at margin to somewhat thicker in the older central areas, smooth to rarely verruculose, shiny, yellowish grey to (rarely) yellowish white, sorediate. Soredia greenish to pale yellow-green, more rarely yellowish white, usually coarsely granular, 40-50 μm wide, arranged in small, round, discrete, crater-like, usually <0.6 mm wide soralia which may become confluent in old specimens. Apothecia unknown. Photobiont chlorococcoid. Spot tests: soralia K-, C+ red, KC+ red, P-, UV+ bright orange. Chemistry: lichexanthone, gyrophoric acid, and lecanoric acid (trace).
Note: a mainly temperate lichen found on isolated deciduous trees with mineral-rich bark. According to Kukwa (2011) the species is more frequent in Fennoscandia and central-eastern Europe, being rare in the western and southern parts of the Continent.
Growth form: Crustose
Photobiont: green algae other than Trentepohlia
Reproductive strategy: mainly asexual, by soredia, or soredia-like structures (e.g. blastidia)