Nash, T.H., Ryan, B.D., Gries, C., Bungartz, F., (eds.) 2004. Lichen Flora of the Greater Sonoran Desert Region. Vol 2.
Pycnidia: immersed to superficial, subglobose, (40-)5080(-110) µm in diam.; wall: composed of dark brown cells of 4-7 µm in diam. conidiogenous cells: (5-)7-9(-11) x (2-)2.5-3.5(-4) µm conidia: brown to dark brown, simple, subglobose, basally not distinctly truncate, verruculose, (2.5-)3-4(-5) µm. Hosts: parasitic, mainly on foliose and fruticose lichens, such as Cladonia s. l., Parmelia s. l., Physcia, Ramalina and Usnea World distribution: Europe, Macaronesia, North and South America, Australasia, and Antarctica, probably cosmopolitan Sonoran distribution: known from one locality in southern California. Notes: Lichenoconium usneae can easily be confused with