Nash, T.H., Ryan, B.D., Gries, C., Bungartz, F., (eds.) 2004. Lichen Flora of the Greater Sonoran Desert Region. Vol 2.
Thallus: fruticose, shrubby, up to 5 cm long branching: irregularly and intricately branched from a common or delimited holdfast branches: solid, flattened in main branches becoming terete or irregularly thickened distally, 0.5-1 mm in diam. surface: pale green to grayish green, smooth to +uneven, often striate, sorediate soredia: coarsely granular often with cylindrical fibrils, in punctiform, lateral or laminal soralia pseudocyphellae: common, ellipsoid or short linear cortex: thin; chondroid strands: continuous or dissected, smooth Apothecia: not seen for the Sonoran material Pycnidia: not observed Spot tests: cortex K-, C-, KC+ yellow, P-; medulla K-, C-, KC-, P- Secondary metabolites: cortex with usnic acid; medulla with homosekikaic acid (major), sekikaic acid (major), and 4'-O-methylnorhomosekikaic acid and 4'-O-methylnorsekikaic acid (both minor). Substrate and ecology: on branches World distribution: cosmopolitan Sonoran distribution: rare in Baja California and Baja California Sur. Notes: Ramalina farinacea is the only species in the Sonoran area that may be mistaken for R. peruviana, but it has broader (up to 3 mm wide) and sparingly branched laciniae and produces depsidones such as protocetraric acid or norstictic acid.