Basionym Name:Placodium ferrugineum var. ferrugineofuscum Vain., Ark. Bot. 8(no. 4): 65 (1909)
Homotypic synonyms:Caloplaca ferruginea var. ferrugineofusca (Vain.) Lynge, Rep. Sci. Res. Norweg. Exped. Novaya Zemlya, 1921 43: 23 (1928)