Rhizocarpon infernulum  

Rhizocarpon infernulum (Nyl.) Lynge
Rhodora 36: 158. 1934
Basionym: Lecidea infernula Nyl., Flora 68: 440. (1885).
Synonym: Lecidea decinerascens Nyl., Flora 68: 445 (1885).—Rhizocarpon decinerascens (Nyl.) Zahlbr., Cat. Lich. Univ. 4: 332 (1926).