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Lecanora confusa Almb.
Family: Lecanoraceae
Lecanora confusa image
Thallus: crustose, granular-warted, warts mostly coalescing to form a rimose-areolate crust areoles: +isodiametric to irregular in outline, 0.1-0.2(-0.4) mm in diam., weakly to strongly convex, or surface irregularly wrinkled, ecorticate but sometimes with a loose unorganised alga-free layer of various hyphae surface: light gray to beige or ochre, with a yellowish or more rarely green tinge, dull, herbarium specimens mostly covered with terpenoid crystals, occasionally with poorly delimited sorediate patches or almost leprose, sorediate soredia: globose, 25-45 µm in diam. Apothecia: rounded or irregular in outline, ±polygonal when densely crowded, single or densely crowded in large groups, sessile with a constricted base or rarely ±appressed, 0.45-0.70(-0.90) mm in diam. disc: light orange-brown to pinkish ochre, rarely with an olivaceous discoloration, flat to weakly (very rarely strongly) convex, white to pale pink, finely or more often coarsely pruinose, dull margin: weakly to strongly prominent when young, persistent, very rarely excluded, concolorous with thallus, slightly crenulate, in herbarium specimens usually densely covered by white terpenoid crystals and byssoid in outer appearance, without a parathecial ring amphithecium: present, with algal cells: in scattered groups throughout amphithecium, laterally 40-155 µm wide, basally 50-190 µm wide, filled with small brownish granules (soluble in K), composed of irregularly entangled, short-celled hyphae with lumina 1-2 µm wide but lumina of outer cells 1-2.5(3) µm wide, ecorticate parathecium: rarely completely missing, usually 10-40 µm wide epihymenium: pale to sordid ochre, sometimes with a green tinge, coarsely (up to 7.5 µm in diam.) granular (soluble in K), 5-15 µm thick hymenium: hyaline to yellowish brown, sometimes with orange- to red-brown stripes, (40-)45-60 µm tall; paraphyses: hyaline, simple or weakly branched and anastomosing, with 1-1.2(-1.5) µm wide but apically 1-2 µm wide lumina; subhymenium: hyaline, 30-90(-140) µm thick; hypothecium: hyaline or pale straw-colored, 40-220 µm thick asci: clavate, 8-spored ascospores: hyaline, simple, rarely 1-septate, ellipsoid, (7-)10-13(-16.5) x (3.5-)4-5.7(6.5) µm Pycnidia: not observed Spot tests: thallus and amphithecium K-, C+ orange, KC+ orange, P- Secondary metabolites: usnic acid, thiophanic acid, ±arthothelin, ±4,5-dichloronorlichexanthone, ±4-chloronorlichexanthone (tr.), ±norlichexanthone (tr.); or usnic acid, zeorin and 1 unidentified xanthone. Substrate and ecology: on tree bark and wood in coastal areas World distribution: oceanic North America and Europe Sonoran distribution: southern California south to northern Baja California at 0-600 m. Notes: Lecanora strobilina, L. perconfusa and L. substrobilina have narrower spores (L. substrobilina also shorter ones). Lecanora strobilina differs also by the lack of xanthones (C- reaction of thallus and apothecia).