Basionym: Diderma squamulosum Alb. & Schwein., Conspectus Fungorum in Lusatiae superioris: 88, t. 4:5 (1805) [MB#214550] Obligate synonym: Cionium squamulosum (Alb. & Schwein.) Spreng., Caroli Linnaei systema vegetabilium 4 (1): 528 (1827) [MB#232738] Taxonomic synonyms: - Didymium applanatum Nann.-Bremek., Proceedings van de Koninklijke Nederlandse Akademie van Wetenschappen Section C 74: 352 (1971) [MB#313076] - Didymium praecox de Bary, Fungi Europaei exsiccati Cent. 4: no. 367 (1861) [MB#142211] - Didymium praecox de Bary ex Rostaf., Sluzowce Monografia: 163 (1875) [MB#841906]