Pseudocyphellaria crassa

Detailed description

Thallus spreading, ± loosely attached, margins ± free and subascendent, to 20 cm diam. Lobes linear-elongate, 5-10 mm wide and 3-5 cm long, ± laciniate, subdichotomously to irregularly branching, margins entire or slightly incised, slightly thickened, ± incurled, brown-pubescent, apices crenulate, sinuous or truncate. Upper surface reddish when wet, pale greyish-fawn or tinged yellowish when dry, shallowly reticulate-faveolate, uneven or smooth, shining, without soredia, isidia, maculae or pseudocyphellae. Medulla white. Photobiont blue-green. Lower surface densely and thickly tomentose to the margins, or with a narrow, glabrous, marginal zone, tomentum dense, brown to blackish. Pseudocyphellae yellow, scattered, round to irregular, frequent, verruciform, 0.1-1.0 mm diam., sunk in tomentum or protruding from it, margins conspicuous, pale to dark brown or black. Apothecia marginal or submarginal, 0.5-3.0 mm diam., sessile to subpedicellate, disc concave at first and entirely obscured by margins, plane at maturity, matt, brown-black, margins thick, persistent pale buff or flesh-coloured, coarsely scabrid-crenulate appearing ± denticulate or coronate, thalline exciple corrugate-scabrid, pale flesh-coloured. Ascospores greenish-brown, fusiform-ellipsoid, 1-3-septate, 23-30 × (3-)7-10 µm.

Chemistry: Pulvinic acid, pulvinic dilactone, calycin, tenuiorin, methyl gyrophorate, hopane-6α,7β,22-triol, stictic, constictic and norstictic acids.