Gyalolechia flavovirescens  

Thallus crustose, large (to ca 15 cm diam), composed of angular greenish orange rimose-areolate areoles with lighter patches, surrounded by a pale grey prothallus.
Anamorph: not known.
Teleomorph: ascomata apothecia, frequent, to 1 mm diam, bright to brownish orange with convex discs with paler margins. Thalline margin thin, grey-yellow, crenulate, soon becoming excluded, retained on the underside of the apothecia. Proper margin prominent, somewhat elevated, smooth. Hymenium lacking oil droplets. Interascal tissue of paraphyses, often branched towards the apex. Ascospores type 1b, 15-20 x 5-10 µm, ellipsoidal, the septum 5-9 µm thick, to around half the length of the ascospores.
Chemistry: all parts K+ purple.