Smithsonian Institution, National Museum of Natural History, Department of Botany – https://mycoportal.org/portal/taxa/index.php?taxon=100818; Owner: CC BY-SA NC
Source: Redinger, K. (1938) Arthoniaceae, Graphidaceae . In Kryptogamen-Flora von Deutschland, Österreich und der Schweiz. Band 9, 2 Abt., Part 1 (G. L. Rabenhorst, ed.): 181–404. Leipzig: Borntraeger. – Public Domain
