Synonymy:
Calicium subtile ++ lenticulare (Ach.) Fr., Sched. Crit. Lich. Suec., Fasc. 1-4: 7 (1824)
Calicium quercinum var. lenticulare (Ach.) Nyl., Syn. meth. lich. (Parisiis) 1(2): 156 (1860)
Calicium quercinum subsp. lenticulare (Ach.) Nyl., Lich. Envir. Paris: 23 (1896)

Mucor sphaerocephalus L., Sp. pl. 2: 1185 (1753)
Lichen sphaerocephalus (L.) Weber, Spicil. fl. goetting.: 198 (1778)
Sphaerocephalum quercus F.H. Wigg., Prim. fl. holsat. (Kiliae): 87 (1780)
Calicium sphaerocephalum (L.) Ach., Methodus qua omnes detectos Lichenes Secundum Organa Carpomorpha ad Genera, Species et Varietates Redigere atque Observationibus Illustrare Tentavit Erik Acharius: 91 (1803)
Calicium claviculare var. sphaerocephalum (L.) Ach., K. Vetensk-Acad. Nya Handl. 29: 279 (1808)
Phacotrum sphaerocephalum (L.) Gray, Nat. Arr. Brit. Pl. (London) 1: 483 (1821)
Calicium subtile + sphaerocephalum (L.) Fr., Sched. Crit. Lich. Suec., Fasc. 1-4: 7 (1824)
Cyphelium claviculare var. sphaerocephalum (L.) Chevall., Fl. gén. env. Paris (Paris) 1: 319 (1826)
Phacotium sphaerocephalum (L.) Trevis., Flora, Regensburg 45(1): 6 (1862)
Cyphelium sphaerocephalum (L.) Saut., Mitteil. Gesellschaft für Salzburger Landeskunde 12: 124 (1872)

Trichia sphaerocephala Hoffm., Veg. Crypt. 2: 15 (1790)
Calicium lenticulare var. sphaerocephalum (Hoffm.) Zahlbr., Cat. Lich. Univers. 1: 610 (1922)

Calicium sphaerocephalum var. majus Schaer., Lich. helv. spicil. 1: 4 (1823)

Calicium subquercinum Asahina, J. Jap. Bot. 8: 2 (1932)

Calicium amylocaule Lettau, Feddes Repert., Beih. 119(no. 3): 184 (1940)

Position in classification:
Calicium, Caliciaceae, Caliciales, Lecanoromycetidae, Lecanoromycetes, Ascomycota, Fungi

Note:
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