Species: Lepraria caesioalba
Photos: Growing over moss on acidic upland rock. Ballingeary, Cork, SW Ireland. Identification confirmed by John Douglass
Thallus forms rosette-shaped patches of greyish granules, often slightly darker in centre.
Found on well-lit siliceous upland rocks, also over-growing mosses and on soil in similar habitats.
Usually K+ faint yellow, C-, P+ orange but very variable.
Lepraria caesioalba growing over moss. March 2009