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Sticta kunthii Hook. f.
Family: Lobariaceae
Sticta kunthii image
André Aptroot  
Thallus: foliose, orbicular to irregularly spreading, 3-7(-9) cm in diam, loosely attached centrally, with free and sub-ascendent margins, rather coriaceous lobes: irregularly laciniate, rather ragged, 10-20(-30) mm wide, 10-30(-35) mm long, discrete to subimbricate at margins, complex-imbricate centrally; margins: entire, sinuous, here and there, shallowly notched or scalloped, thickened below with a distinct, dark rim upper surface: when wet dark lead-gray to blue-black marginally and paler centrally, when dry pale gray-blue or glaucous gray and suffused brown, with minute, white, marbled maculae (x10 lens, moist), smooth or shallowly wrinkled, often with minute, pale-buff or white, scattered to crowded papillae (x10 lens), dull, without isidia, phyllidia or soredia medulla: white, K- photobiont: cyanobacterial lower surface: pale-buff to chocolate brown, tomentose from margins to center, sparse and rather cobwebby, to entangled-woolly, rhizinate; rhizines: occasionally with fascicles of long rhizines (up to 4 mm long) centrally, also here and there with projecting, solitary to fasciculate brown-black rhizines up to 1 mm long cyphellae: common, scattered, prominent, minute, pin-prick-like at margins, round to ellipsoid, (0.1-)0.3-1(-1.5) mm in diam. centrally, with flat, pale, "halo-like" margins, with a white basal membrane Apothecia: occasional to frequent, marginal and laminal, best developed and often clustered towards lobe apices, sessile, constricted at base, round, (0.5-)1-2(-2.5) mm in diam. disc: orange to orange-brown and translucent when moist, red-brown and dull when dry, epruinose margins: pale pinkish buff to cream-colored, coarsely corrugate, scabrid, obscuring disc at first, persisting, crenulate to ragged at maturity, often with projecting, silky, glistening, white to brownish cilia 0.2-0.6(-0.8) mm long); epihymenium: pale yellow-brown to orange-brown, 7-12 µm thick hymenium: hyaline, 75-95 µm tall; hypothecium; opaque, yellow-brown, 50-80 µm thick asci: clavate, 55-70 x 10-13.5 µm, 8-spored ascospores: hyaline to pale yellow-brown, 1-3-septate, fusiform-ellipsoid, with pointed apices, 25-30(35) x 5.5-8.5(-10) µm Pycnidia: occasional, scattered, developed towards margins, immersed but apparent as distinct, pale buff or pale brown swellings, 0.2-0.5(-0.8) mm in diam., with a central, depressed red-brown to brown-black ostiole conidia: bacilliform, straight, 3-5 x 1 µm Spot tests: all negative Secondary metabolites: none detected. Substrate and ecology: pine-oak forest, on Quercus, 2320 m World distribution: neotropical in Mexico, Colombia, Venezuela, Peru, Brazil Sonoran distribution: Sinaloa (only one collection seen).