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(-10) cm long branching: palmately or irregularly branched, growing from a common holdfast branches: solid, main branches monophyllus with marginal secondary branches 3-10(-15) mm wide surface: greenish yellow to pale stramineous on the upper surface, greenish yellow to brown on the lower surface, dull, reticulately ridged soredia: present, laminal or marginal pseudocyphellae: rare, sparse or almost lacking, orbicular, flat cortex: very thin, composed of a single prosoplectenchymatous layer, lacking chondroid strands or sheath Apothecia: not seen for Mexican specimens Pycnidia: not observed Spot tests: cortex K-, C-, KC+ yellow, P-; medulla K-, C-, KC-, P- Secondary metabolites: cortex with usnic acid (major); medulla with bourgeanic acid (major). Substrate and ecology: on branches, rarely on rock World distribution: widespread in the Mediterranean region of Europe, South Africa, Chile and North America Sonoran distribution: common in Baja California and Baja California Sur. Notes: Differences of R. lacera with R. canariensis are elaborated under that species. Because of its thin, single-layered cortex lacking inner chondroid tissue, Choisy placed R. lacera in the genus Dievernia. However, this character alone is insufficient grounds to recognize a different genus, and consequently Dievernia is regarded as a synonym of Ramalina in this treatment.