Description: This tiny, though abundant, grey-green crustose lichen grows widely on siliceous rocks and walls. It forms very small (0.5-2.0cm diam.) areolate thalli covered with yellow-green to pale brown discs that can coalesce to form larger patches. Common: rocks and walls, also on worked timber in remoter areas and along the coast.

Key Identification Features:

• Small patches, with scattered or crowded yellow-green discs
• Discs never emerald green on a thick crust.

Original text submitted by Vince J. Giavarini

Distribution Map from NBN: Lecanora polytropa at National Biodiversity Network mapping facility, data for UK.

iNaturalist: Lecanora polytropa at iNaturalist World Species Observations database.