Description: This eye-catching species of well-lit, horizontal limestone forms low-growing, white, cushion-like crusts with neatly lobed margins spread out like a fan. The entire surface, other than the discs, dazzles in the sun as though sprinkled with white icing sugar. The flat, grey-blue to black discs contrast strongly with the thallus. Spot tests: K-; Pd+ orange. It is sometimes confused with Diploicia canescens, which is sorediate, K+ y, Pd-, and widely tolerant of nutrient and dust. In Ireland, S. candicans is best known from the limestone of the Burren, County Clare and from County Sligo.

Key Identification Features:

• Thallus: snow white, lobed and low, cushion-forming, radiating at the edges like a fan; K-, Pd+ orange
• Discs blue-black usually concentrated towards the centre of the thallus; hard limestones including memorials in cemeteries and churchyards.

Original text submitted by Vince J. Giavarini

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

iNaturalist: Solenopsora candicans at iNaturalist World Species Observations database.