Psoroma pallidum Nyl.
Details
Nomenclature
Nyl.
Nyl.
1863
25
ICN
Psoroma pallidum Nyl.
species
Psoroma pallidum
Classification
Descriptions
Psoroma pallidum Nyl.
Thallus foliose-lobate, closely attached centrally, free at margins, without a prothallus, 6-10(-20) cm diam. Lobes laciniate, radiating, discrete not imbricate, subdichotomously to irregularly branched, 2-5 mm wide, 6-25 mm long, margins minutely notched, irregular, knobbly in parts or in parts entire and sinuous, conspicuously downrolled and thickened. Upper surface distinctly roughened-irregular, uneven, cortex fibrous, subplicate in parts, lumpy, pruinose in places or minutely white-tomentose, hairs silky, short, bright green when wet, pale greenish-grey or yellowish-green-glaucous when dry. Lower surface white at margins, uniformly thick, buff, tomentose centrally, tomentum striate, of hyphae arranged parallel to the length of the lobes, ± thickly rhizinate centrally. Rhizines short, to 2 mm, simple to squarrose, brown or buff. Cephalodia absent from upper surface or rarely developed marginally in older parts of thallus, ± common on lower surface among rhizines and on tomentum, simple, globose, buff or brown, becoming glomerulate-wrinkled. Apothecia numerous, clustered, central, rarely marginal, sessile to subpedicellate, 0.5-4.0 mm diam., disc red-brown, smooth, never gyroseetched or fissured, densely bluish-white-pruinose at first, glabrous at maturity, plane or concave, margins concolorous with thallus, waxy, ± shining, or dull, crenulate-sulcate, ± obscuring disc at first, thalline exciple verrucose-areolate. Ascospores globose, 11-15 µm diam., epispore 2 µm thick.
Taxonomic concepts
Metadata
533560d7-d015-4261-b1e4-75fe8bb3c10b
scientific name
Names_Plants
1 January 2000
24 February 2009