Basionym Name:Lecidea improvisa var. extensa Vain., Meddn Soc. Fauna Flora fenn. 2: 65 (1878)
Homotypic synonyms:Biatorella extensa (Vain.) Räsänen, Ann. bot. Soc. Zool.-Bot. fenn. Vanamo 12(no. 1): 169 (1939)Biatorella improvisa var. extensa (Vain.) Vain., Meddn Soc. Fauna Flora fenn. 10: 143 (1883)Biatorella moriformis var. extensa (Vain.) Blomb. & Forssell, Enum. Pl. Scand.: 83 (1880)