Primary squamules persistent or disappearing, medium, rarely large, 2-8(-10) × 1 mm, irregularly pinnate, subpinnate or subdigitate or laciniate, crenate, often wedge-shaped, ascending, flat or involute, scattered or tufted, rarely caespitose or forming a compact crust, upper surface glaucescent or whitish or olive-green to brownish, lower side white, without soredia or partly granular. Podetia growing from upper surface of primary squamules, very variable in size and shape, base persistent or dying away, 10-90 mm tall and to 2.5 mm diam., cups common, rather abruptly flaring, small to medium, usually widely perforated, margins repeatedly proliferating, cupless podetia branching radiately or irregularly with sterile proliferations which may be blunt or pointed, or branches tipped with apothecia, proliferations simple to clustered and grouped in close tufts, sometimes scattered, often decorticate but not sorediate. Cortex variable ± continuous, or with scattered, corticate areas, or completely absent, decorticate areas retaining inner part of medulla and appearing arachnoid, corticate areas smooth to wrinkled, whitish to bluish- or glaucescent-grey to grey-green, olive-green or brown, blackened in exposed habitats, decorticate areas white, sides of podetia squamules. Apothecia small, on cup margins or on tips of branchlets, pale yellowish to dark brown. Chemistry: Two chemodemes. (i)Squamatic (UV+) ± barbatic acids. (ii) Thamnolic, decarboxythamnolic ± barbatic acids.