Nash, T.H., Ryan, B.D., Gries, C., Bungartz, F., (eds.) 2004. Lichen Flora of the Greater Sonoran Desert Region. Vol 2.
Thallus: foliose, adnate to loosely adnate, 4-12 cm in diam., irregularly lobate lobes: subirregular to sublinear, elongate, plane to subconvex, separate, contiguous to somewhat imbricate, 1.5-4 mm wide, not lobulate; apices: subrotund, smooth to crenate, eciliate upper surface: yellow-green, smooth, shiny, epruinose and weakly maculate, moderately to densely isidiate isidia: initially subglobose, soon becoming cylindrical, simple to sparsely branched, 0.08-0.15 mm in diam., 0.2-1 mm tall; tips: syncorticate, pale brown, sometimes weakly erumpent; soralia and pustulae absent medulla: white, with continuous algal layer lower surface: pale to medium brown, plane, moderately to densely rhizinate; rhizines: pale brown, simple, 0.5-1 mm long Apothecia: rare, substipitate, 2-7 mm wide, laminal on thallus; disc: cinnamon-brown to dark brown; margin: smooth, pruina absent asci: clavate, 8-spored ascospores: hyaline, simple, ellipsoid, 9-10 x 4-5 µm Pycnidia: rare, immersed conidia: bifusiform, 5-6 x 0.5 µm Spot tests: upper cortex K-, C-, KC-, P-; medulla K-, C-, KC-, P+ orange Secondary metabolites: upper cortex with usnic acid (major); medulla with succinprotocetraric acid (major), fumarprotocetraric acid (major or minor), protocetraric acid (minor) and sometimes with virensic and physodalic acids (minor or trace). Substrate and ecology: on acidic rocks, often in open, sometimes marine-influenced, subtropical habitats World distribution: eastern Asia, Africa, North and South America and Oceania Sonoran distribution: common in southern California, Baja California Sur, Sonora and Sinaloa. Notes: Xanthoparmelia subramigera is the only isidiate species in the region with a brown lower cortex and medullary fumarprotocetraric acid as the major secondary metabolite. It occurs fairly commonly in Oceania, and is relatively common in coastal to somewhat inland areas.