Thallus thin to thick (up to 200 µm in thickness), smooth, ± uneven, usually continuous, greyish fawn to pale ochraceous, mainly superficial, medulla in section with numerous crystals (calcium oxalate) which are particularly well-developed in the thallus margin of the ascomata. Anamorph: not known. Teleomorph: ascomata apothecia, numerous, discrete, ± evenly dispersed, (0.6-) 1-2 mm diam., immersed in hemispherical warts, urceolate, ostiolar opening to 0.5 mm wide, white; thalline exciple entire; true exciple free, ± conspicuous when viewed through the ostiole, colourless, not striate; disc blackish, often ± white-grey pruinose, normally visible through an irregular hole in the true exciple; hymenium (120-) 140-190 (-200) µm tall. Asci (1-) 2- to 4- (to 8-) spored. Ascospores broadly fusiform, (30-) 60-135 (-150) × (10-) 15-25 (-33) µm, remaining colourless when mature, with (8-) 10-15 (-19) transverse and 1-3 (-5) longitudinal septa, I± weakly purple, with a thick gelatinous coat. Chemistry: thallus and medulla C–, K–, KC–, Pd–, UV– (lichen products not detected by TLC but sometimes with internal crystals K+ yellow changing to red).