Cliostomum flavidulum Hafellner & Kalb
n Kalb & Hafellner, Herzogia, 9, 1-2: 61, 1992.
Synonyms: Lecanora navarrensis Etayo
Distribution:
Description: Thallus crustose, continuous to rimose, ecorticate, pale yellowish to yellowish green, often surrounded by a thin, whitish to bluish black prothallus, forming small, usually <2 cm wide patches, soon dissolving into diffuse, pale sulphur yellow or yellow-green soralia, the soredia loosely aggregated, farinose, 10-25(-35) µm in diam. Apothecia rare, biatorine, 0.3-0.7 mm across, with a concave to convex, pale yellow. grey-violet or bluish black, often white-pruinose disc, and a concolorous or paler, at first raised and distinct, finally often excluded, usually esorediate proper margin. Excipular hyphae with globose to ellipsoid lumina, the outer rim of exciple and epithecium with small colourless crystals soluble in K, and varying amounts of a green pigment (K- , N+ purple), apothecia otherwise colourless and without crystals in section; hymenium 40-50 µm high, I+ blue; paraphyses simple or sparingly branched in upper part, 1-1.5 µm thick at mid-level, the apical cells clavate or not thickened. Asci 8-spored, cylindrical-clavate, the tholus with a conical, blunt, sometimes indistinct ocular chamber and a distinctly conical axial body, the remainder of tholus I+ dark blue, darkest around the axial body. Ascospores (0-)1(-3)-septate, hyaline, ellipsoid, straight or slightly curved, 8-14 x 2.5-4 µm. Pycnidia rare, immersed, with a gaping ostiole, colourless except for a narrow bluish black zone around the ostiole (the pigment blue-green, K-, N+ purple). Conidia pyriform, 2-2.5 x l.5-2 µm. Photobiont chlorococcoid. Spot tests: thallus K- or K+ faintly yellow, C-, KC-, P+ red, UV-; soralia K+ yellowish, then dirty brown-red. Chemistry: thallus with fumarprotocetraric acid (major), plus traces of atranorin and protocetraric acid.Note: on both broad-leaved and coniferous trees in forests and open woodlands in areas with an oceanic climate; widespread in Western Europe, with a few records from the northern rim of the Alps; to be looked for in Italy.
Growth form: Crustose
Substrata: bark
Photobiont: green algae other than Trentepohlia
Reproductive strategy: mainly asexual, by soredia, or soredia-like structures (e.g. blastidia)
Restricted to humid-warm, oceanic areas

Predictive model
Growth form: Crustose
Substrata: bark
Photobiont: green algae other than Trentepohlia
Reproductive strategy: mainly asexual, by soredia, or soredia-like structures (e.g. blastidia)
Restricted to humid-warm, oceanic areas

Predictive model