THALLUS: whitish, smooth to rugose
APOTHECIA: round, 0.75-2.0 mm; disc pinkish, heavily white pruinose
SPORES: 8 spores, 45-65(-88) x 25-40(-50) µm
CHEMISTRY: thallus KC+ yellow (variolic acid?), disc C+ and KC+ red (gyrophoric acid)
Temperate northern hemisphere into Australasia.
Rough, whitish crustose lichen on coastal rocks, with big thick-rimmed pinkish apothecia.
Acidic to slightly basic rocks in humid, often coastal habitats.