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Usnea subscabrosa Mot.
Family: Parmeliaceae
Usnea subscabrosa image
Stephen Sharnoff  
Thallus: erect-shrubby, 2 to 10 cm long, stiff and shiny branching: anisotomic- to isotomic-dichotomous, divergent basal part: concolorous with the branches, frequently red-brown pigmented at the very base, rarely partially black branches: tapered, cylindrical; lateral branches: not narrowed at attachment point; foveoles and transversal furrows: absent segments: terete, cylindrical papillae: absent to abundant, mainly verrucose tubercles: present fibrils: absent to numerous, short (2-3 mm) to long (5-10 mm), irregularly distributed soralia: punctiform to half width of branch bearing them, arising from cortex and/or tops of tubercles, plane to convex or capitate, rarely slightly concave, ┬▒circular to irregular, transversally or longitudinally oblong, discrete or fusing together isidiomorphs: nearly absent to abundant, on young and mature soralia pseudocyphellae: inconspicuous, ellispoid to linear cortex: thick (11-17%), vitreous, smooth and hard, occasionally with longitudinal cracks, seldom red-spotted medulla: thin, compact, not pigmented axis: thick, not pigmented Apothecia: not seen Spot tests: K-, C-, KC-, P+ yellow turning reddish orange or K-, C-, KC-, P- Secondary metabolites: protocetraric acid (major), ┬▒fumarprotocetraric acid (minor), or rarely none detected. Substrate and ecology: on bark (Quercus spp., Pinus spp. and on shrubs in coastal shrubs communities), rarely on rock, between 0 and 300 m World distribution: southwestern Europe, Macaronesia, eastern and western North America, South America Sonoran distribution: coastal southern California, including the Channel Islands, and Baja California, and the Sierra Madre Occidental of Sinaloa. Notes: Usnea subscabrosa is characterized by a thick, hard, and vitreous cortex, a compact medulla, a basal part that is frequently red pigmented, cylindrical branch segments, minute soralia and the presence of protocetraric acid in the medulla. Usnea hesperina differs by having a dull and soft cortex and U. ceratina by having stipitate soralia, a pink pigment in the medulla and a different chemistry.
Usnea subscabrosa image
Gary Perlmutter  
Usnea subscabrosa image
Stephen Sharnoff  
Usnea subscabrosa image
Usnea subscabrosa image
Usnea subscabrosa image
Usnea subscabrosa image
Usnea subscabrosa image
Usnea subscabrosa image
Usnea subscabrosa image
Usnea subscabrosa image
Usnea subscabrosa image
Usnea subscabrosa image
Usnea subscabrosa image
Usnea subscabrosa image
Usnea subscabrosa image
Usnea subscabrosa image
Usnea subscabrosa image