Nouv. Fl. Environs Paris, Edn 2 1: 202 (1821).

Basionym: Lichen pustulatus L., Sp. pl. 2: 1150 (1753).

Thallus: umbilicate, isidia black, densely branched, upper side of thallus extensively covered by a white, coarsely granular necral layer (Krog 1987: 211).