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Psora pacifica Timdal
Family: Psoraceae
Psora pacifica image
Stephen Sharnoff  
Squamules: up to 3 mm wide, elongate, imbricate to ascending, weakly concave to weakly convex upper surface: medium to castaneous brown, dull or somewhat shiny, epruinose or partly pruinose, smooth margin: concolorous with upper side, down-turned or straight, crenulate or lobed upper cortex: up to 35-65 µm thick, composed of thick-walled hyphae with angular lumina, containing crystals of lichen substances but no calcium oxalate medulla: containing lichen substances but no calcium oxalate lower cortex: poorly developed, composed of mainly periclinally oriented hyphae, not containing calcium oxalate lower surface: white to pale brown Apothecia: up to 1.3 mm diam., laminal, immarginate or marginate when young and later becoming immarginate, medium brown to reddish brown, epruinose ascospores: ellipsoid, 10-14 x 5-7 µm Pycnidia: unknown Spot tests: upper cortex and medulla K-, C+ red, KC+ red, P- Secondary metabolites: gyrophoric acid, trace of lecanoric acid, and usually small amounts of an apparently related compound. Substrate and ecology: on soil in open habitats, often in coastal hillsides, up to 440 m World distribution: west coast of North America Sonoran distribution: uncommon in California and Baja California. Notes: The C+ red and KC+ red reactions in the cortex are difficult to observe.