Thallus: adnate to somewhat more loosely adnate; ± appressed, foliose, up to 7 cm diam., lobate lobes: short and rounded, contiguous to somewhat imbricate, (0.5-) 1-2 (-3) mm broad, ± flat upper surface: reddish brown to dark olive-brown, often paler and more yellowish at the periphery, smooth on the lobe ends, inward often becoming rather strongly rugose; dull throughout or slightly shiny on the lobe ends, sometimes lightly pruinose on some lobe ends isidia: sparse to dense, pustular, 0.05-0.3 mm in diam., sometimes clustered lower surface: dark brown to black, sometimes much paler on the lobe ends, ± smooth and dull; moderately rhizinate, the rhizines concolorous with the lower surface pycnidia: not seen Spot tests: cortex K-, C-, KC-, P-, HNO3+ dark blue-green; medulla: K+ yellow tuming red, C-, P+ very pale orange or P- Secondary metabolites: hypostictic acid (major), hyposalazinic and hypoconstictic acids (both minor), usually with a trace of unknown TE-2 (Esslinger1977). Substrate: rock World distribution: western North America, South America, New Zealand, South Africa Sonoran distribution: see note below. Notes: This species is most like N. loxodes, with similar thallus coloration and pustular isidia, but clearly distinguished by the production of hypostictic acid and other related ß-orcinol depsidones in the medulla. The K+ spot test will easily distinguish N. subhosseana from N. loxodes. Neofuscelia subhosseana has not yet been found from the Sonoran Region as defined for this study. However, it occurs just outside the study area, in central California (San Mateo and Mono Counties) and in Utah (Zion National Park), and seems a likely candidate to eventually be found here as well.