Aspicilia cinerea  

Thallus areolate to rimose on a shiny black hypothallus, areoles to 1 mm diam., very irregular, becoming warted or with knobbly papillae along margins in nutrient-rich environments, smooth, dull grey, becoming brown-tinged, grey-brown or rarely rust-coloured or green; prothallus black, visible both between the areoles and at the edge of the thallus. Isidia and soredia absent. Photobiont chlorococcoid algae.
Anamorph: conidiomata pycnidia, with filiform conidia 11-16 × ca 1 μm in size.
Teleomorph: ascomata apothecia, (0.2-)0.4-1.2(-2) mm diam., 1-2 per areole, at first immersed, later sometimes becoming sessile or slightly protruding. Thalline margin thick, not convoluted, white to pale grey, persistent. Disc slightly concave to flat, matt black. Interascal tissue composed of paraphyses, simple to sparingly branched, frequently anastomosed, short-celled and moniliform above, the apices cohering to form a well-defined epithecium. Asci clavate, thin outer coat K/I+ blue, wall and apical dome K/I–, (6-)8-spored. Ascospores 12-22 × 6-13 μm, broadly ellipsoidal, hyaline, aseptate, thin- and smooth-walled, without a gelatinous sheath or perispore.
Chemistry: thallus K+ red, Pd+ orange (norstictic acid).

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