Description: This small, orange crustose lichen will be among the first seen growing on newly built masonry such as low walls and concrete posts. Barely 1cm across, the grey to black thalli soon become crowded with convex orange (never yellow) discs, the margins thin and shiny, and often excluded with age. Common: calcareous stone, wall tops, brickwork and mortar. Less frequent on tree bases.

Key Identification Features:

• Small thallus (1cm diam.) of crowded, orange discs
• Between the discs: thallus a dirty grey, darkening to black in some polluted, urban areas.

Original text submitted by Vince J. Giavarini

Distribution Map from NBN: Athallia holocarpa s. lat. at National Biodiversity Network mapping facility, data for UK.

iNaturalist: Athallia holocarpa s. lat. at iNaturalist World Species Observations database.