Thallus: foliose, orbicular, tightly adnate to adnate, 2-7 (-8) cm diam., closely appressed, deeply lobed lobes: sublinear, ± irregularly dichotomous, generally contiguous to overlapping, 5-15 mm long, 0.3-1 mm wide; tips: broadened, rounded or crenate upper surface: whitish to light or ashy or sometimes dark gray, brownish at the tips, dull or shining soredia: granular (to somewhat powdery), white to white-gray or blue-gray, in well-delimited, round, capitate, and ± convex soralia; soralia: laminal (scattered to contiguous) or subterminal (at the tips of short, adnate or somewhat ascending lobes) upper cortex: brownish, 16-20 µm thick medulla: white, loose, of 4 µm thick hyphae; algal layer: continuous or interrupted lower cortex: 16-20 µm thick lower surface: tan to dark brown, becoming black towards center; rhizines: short, simple, dark, up to the margins Apothecia: very rare, laminal or marginal, slightly pedicillate, up to 2 mm diam.; thalline margin: whitish or brown, crenulate, sometimes becoming sorediate; disc: pale or dark brown, shiny, flat or becoming convex, epruinose; epihymenium: 14-30 µm brown or yellow-brown; hymenium: hyaline or yellowish ascospores: short ellipsoid or bacilliform with the ends rounded, 8-15 x 1.5-5 µm Pycnidia: rare, on lobe tips conidia: falcate, 16-22 x 0.5-0.8 µm Spot tests: upper cortex K+ yellow, C-, KC-, P- or + pale yellow, UV-; medulla K-, C-, KC- or faintly purplish, P-, UV+ white Secondary metabolites: upper cortex with atranorin and chloroatranorin, medulla with divaricatic acid. Substrate and ecology: common on conifers (especially Pseudotsuga) and old stumps, burned logs, old wood, rare on acid rocks, often on or near the bases of trees, below the snowpack; in open to shady moist forests, often with P. ambigua World distribution: circumpolar; North America, Europe and northern Asia; also in South America Sonoran distribution: common in Arizona at high elevations (2900-3535 m) in pine-fir and spruce-fir forests; also found in Baja California. Notes: As pointed out by Hinds (1999), although P. hyperopta has been considered as differing from P. ambigua mainly in chemistry (cortex with atranorin rather than usnic acid, reflected in the color of the upper surface), it also differs somewhat morphologically, e.g., in having more often terminal, capitate soralia and on the average somewhat longer ascospores, and also perhaps (Thomson 1984) a thicker pigmented layer in the upper part of the hymenium. Parmeliopsis hyperopta can be distinguished from sorediate Physcia spp. (most of which occur on rocks at lower elevations in the Sonoran region) by the somewhat shiny upper surface near the lobe tips, presence of divaricatic acid in the medulla, and occurrence over acidic bark. Similar species in eastern North America include Physcia americana (which is white below and has a K+ yellow medulla). Essentially all other gray, sorediate parmelioids in the Sonoran region are larger, more robust and more loosely adnate; a few Hypotrachynae are closest, but they have dichotomous rhizines.