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Alyxoria ochrolecheila (Nyl.) Ertz & Tehler (redirected from: Opegrapha ochrocheila)
Family: Opegraphaceae
[Opegrapha ochrocheila Nyl.]
Alyxoria ochrolecheila image
André Aptroot  
Life habit: lichenized Thallus: very thin or immersed, inconspicuous, smooth or cracked surface: whitish, rarely tinged brownish or olive-green Ascomata: sessile, (0.3-)0.5-1.2(-2.5) x 0.2-0.4(-0.5) mm, simple or rarely branched, scattered or contiguous; exciple, and sometimes the disc, ± encrusted with a bright orange pruina of unknown composition, K+ purplish; disc a slit, frequently widening exciple: closed hymenium: 50-60 µm tall, I+ red; epihymenium reddish brown, I+ blue; hypothecium pale brown, 15-25 µm, I+ blue; paraphysoids to 1.5 µm asci: claviform, 45-50(-55) x (13-)15-18 µm (Varia-type) ascospores: 13-21 x 4-5 µm, ellipsoid or somewhat clavate, 3-septate (Calcarea-type) Pycnidia: subimmersed, often covered by a red-orange pruina conidia: straight or sinuate, 10-14 x 1.5 µm, 1-3-septate Spot tests: thallus K± purplish, C-, KC-, P-, UV± orange or glaucous; ascomata sometimes K+ red, with the red color diffusing out in the surrounding thallus Secondary metabolites: (± two UV+ pigments). Substrate and ecology: on old, dry, shaded bark, especially oaks, often on wood, more rarely on sheltered siliceous rocks World distribution: western Europe; North America (British Columbia; California; Coahuila, Mexico), Yemen Sonoran distribution: southern California and Baja California Sur. Notes: Specimens of O. ochrocheila without pycnidia and with epruinose ascocarps are easily mistaken for O. herbarum, which has longer and broader ascospores with the second cell in the upper half comparatively larger. O. atra differs in having narrower ascospores, a K+ distinctly olive-green exciple and a narrow slit-like hymenial disc which becomes only slightly widened when old.