Description: This is a crustose epiphyte mainly found in long-established and ancient woodlands. In Ireland, it is known from Killarney, County Kerry and from County Cork. Superficially it is almost identical to B. disciformis but occurs on less smooth bark and tests K+ yellow-red. Under the microscope, the internal structure of the discs will be seen to lack oil droplets so abundant in B. disciformis. In Killarney, the species grows in swamp woodlands.

Key Identification Features:

• Like B. disciformis but lacks oil droplets when viewing disc in squash and is K+ yellow-red not K+ yellow
• In ancient woodlands where it colonises slightly more roughened bark.

Original text submitted by Vince J. Giavarini

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

iNaturalist: Buellia erubescens at iNaturalist World Species Observations database.