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Lecidea leucothallina Arnold
Family: Lecideaceae
Lecidea leucothallina image
Ecology: Biotroph; lichenized; episubstratic; substrate non-calciferous or metalliferous. Thallus: Areolate (primarily areolate), subsquamulose, continuous throughout, dispersed along the periphery, continuous in the centre, or dispersed throughout and distinctly seperate; lobes angular or rounded at the front; separate thallus parts.2-.4 mm thick. Thallus Size and Differentiation: Large; main branches basally not constricted or rarely basally constricted. Upper Surface: Lemon (citrine) or brown (pale beige to very pale brown), plane or convex; not sorediate; without thalloconidia thalloconidia. Upper Cortex: Epicortex present. Medulla: Iodine reaction in Lugol's solution negative. Ascocarps: Forming rarely on the pro- or hypothallus, soon sessile, slightly constricted or strongly constricted at the base, 12-180 per cm², .6-1.3-(2.3) mm in diam.. Margin: Not flexuose or slightly flexuose, persistent or excluded, 30-60 µm wide, epruinose. Disk: Plane or weakly convex to rarely strongly convex, rarely black or brown, epruinose, pruina scarce or abundant, without an umbo. Exciple: Hyphae radiating outwards; 3.5-5 µm wide; grey or brown; not inspersed with crystals or inspersed with crystals. Epithecium: Apical cells olive or black, cell pigment reacting with 10% HCl (in H2O). Hymenium: 40-(mean: 43-49)-55 µm high; white; iodine reaction: Lugol’s positive. Subhymenium: 5-(mean: 12-17)-27 µm high; white. Hypothecium: Brown or dark brown. Ascospores: Ellipsoid or oblong, (5)-6.6-10.4-(14) µm long, (3.2)-4-4.7-(6) µm wide; wall not ornamented. Conidia: (11)-13.5-16.5-(20) µm long. Secondary Metabolites: Not detected. Spot Tests: Medulla: K –, C –, PD – (TEST!!) or + orange (control cortex microscopically!); ascocarp margin (in section): K –, C – disk: PD + orange; hypothecium: K – epihymenium: K –.