Description: Primary thallus squamulose, persistent or usually disappearing, the squamules small to middle-sized, 2-5 mm long (rarely more), up to 4 mm broad (usually less), more or less round, crenate to incised, ascending, glaucescent above, white beneath. Podetia to 5(-8) cm tall (usually much less) and up to 4 mm thick, hollow inside, with irregular, 1-3 mm wide, usually closed cups which often proliferate marginally, the margins often squmulose, grey, brownish grey or dark brown in exposed situations, the base strongly melanotic also in the medulla (in upper basal parts black interspaces are visible between the cortical areoles), with a subarachnoid surface (the part between corticate areolae is ecorticate and subtomentose), variously squamulose. Apothecia rather rare, brown, convex, on the tips of the proliferations. Asci 8-spored, clavate, thickened at apex, with a K/I+ blue tholus and a K/I+ strongly blue outer gelatinous sheath, Cladonia-type. Ascospores 1-celled, hyaline, ellipsoid. Pycnidia dark brown, semi-immersed on the margins of cups or on the proliferations, with a colourless jelly. Conidia bacilliform. Photobiont chlorococcoid. Spot tests: K-, C-, KC-, P+ red, UV-. Chemistry: fumarprotocetraric acid complex, rarely zeorin and traces of an unknown compound.
Note: a cool-temperate to boreal-montane, probably holarctic lichen found on acid mineral soil. Records from southern Italy (see Nimis 1993: 239), being dubious, are not accepted here.
Growth form: Fruticose
Substrata: soil, terricolous mosses, and plant debris