Psoroma contextum Stirt.
Details
Psoroma contextum Stirt. (1877)
Nomenclature
Stirt.
Stirt.
1877
294
ICN
Psoroma contextum Stirt.
species
Psoroma contextum
Classification
Descriptions
Psoroma contextum Stirt.
Thallus squamulose, very closely attached, spreading, 4-6(-10) cm diam., prothallus only rarely present, black, thin, somewhat eroded, scattered. Squamules small, 1-3 mm diam., flattened, lobate-crenate, distinctly placodioid at margins, pressed together, separated by fine black cracks like a jigsaw puzzle, rarely imbricate at margins, becoming minutely lobulate and subimbricate centrally in a close mosaic, surface smooth, waxy, shining, margins not pubescent- frosted, dark green to pale green or whitish or yellowish-grey not darkening on storage. Cephalodia rare, simple, globose to ± glomerulate, not flattened- placodioid, pale brown-grey, surface smooth, not wrinkled or striate-cracked, developed below squamules, protruding from margins of squamules, to 0.8 mm diam. Apothecia sessile to subpedicellate, scattered to crowded, projecting above squamules, round to subirregular, to 2 mm diam., margins concolorous with thallus, waxy, crenate-striate, obscuring disc in young fruits, disc red- brown, matt, often darkening centrally, rarely with a single to a few thalline lobules centrally, plane or subconcave, not etched-contorted, fissured or pruinose. Ascospores ellipsoid to fusiform 18-24 × 12-17 µm.
Taxonomic concepts
Psoroma contextum Stirt.
Psoroma contextum Stirt.
Metadata
a9b2943d-a83a-4f94-aba3-6db2877c7d52
scientific name
Names_Plants
1 January 2000
2 June 2011