Ascomata: unknown Conidiomata: superficial, arising singly or irregularly confluent, stromatic, black, convex, basally constricted, immarginate, mostly 50-75 Ám in diam., composed of hyaline, globose, thick-walled cells up to 8 Ám in diam., becoming brown towards the edge, stroma surrounded by a brown pellicle-like layer iophores: indistinguishable from the hyaline, subspherical cells of the stroma conidiogenous cells: hyaline to pale brown, subcylindrical, 2-3 Ám in diam., 2.5-4 Ám long, located within the stroma, at first producing apically c. 2-3 pale brown, small, subspherical cells; during maturation, these cells become more numerous, up to 12 or more, larger, 4-6 Ám in diam., and dark brown conidia: consisting of the initial conidiogenous cells surrounded by the brown subspherical cells, forming a compact, multicellular, dark brown, ellipsoid aggregate, 15-25 Ám in diam.; individual cells: 4-6 Ám in diam. Hosts: on the thallus of epiphytic, mainly fruticose macro-lichens (Bryoria, Evernia, Flavoparmelia, Letharia, Lethariella, Parmeliopsis, Pseudevernia, Ramalina, Usnea); in the Sonoran region known from Ramalina and Usnea World distribution: cosmopolitan Sonoran distribution: Arizona and southern California. Notes: Phaeosporobolus usneae looks very similar to Lichenostigma maureri, known to occur on the same host spectrum, and can hardly be distinguished macroscopically. Microscopical examination of squash preparations is therefore always required for an accurate identification.