TYPE. SWEDEN. “Habitat ad rupes inter muscos & ad scandula inundata lignea.” (Acharius 1798)
Description.Life form: lichenized fungus.
[Modified from Fletcher & Giavarini (2009)] Thallus filamentous, brown-black to black, to 1 cm diam., filaments erect, forming button-like cushions, lacking rhizoidal hyphae, each a filament of photobiont with fungal hyphae loosely interwoven, knobbly and obscured within the gelatinous sheath of the photobiont; filaments to 15 µm diam., radiating, simple or sparingly false-branched, cells penetrated by short, capitate haustoria. Photobiont Scytonema cyanobacterium. Ascomata apothecia, lateral on filaments, globose, 0.2-0.5 mm. diam., sessile; disk poriform, proper exciple distinctly swollen, 50-70 µm wide, brown at outer edge, hyaline within; hymenium 100-150 µm tall, hyline or brown in the upper part, I+ blue; hamathecium of simple, septate paraphyses, apices swollen; hypothecium 80-130 µm tall, hyaline. Asci cylindrical, 60-100 × 5.5-7 µm, 8(-12)-spored, thin walled, apical dome K/I+ blue. Ascospores simple, ellipsoid, colourless, 9-15 × 5-7 µm. Conidiomata pycnidia, lateral, red-brown; conidiogenous cells narrow, acrogenous; conidia simple, globose, colourless, 1-1.5 µm diam.
Chemistry. Not reported.
Substrate and Habitat. Semi-aquatic on rocks and wood near streams.
Distribution. Europe North and South America; in North Carolina found in Piedmont ecoregion.
Literature
Acharius, E. (1798) Lichenographiae Sueciae Prodromus. Lincopiae, D.G. Björn, 264 pp (orginal description as Lichen velutinus).
Fletcher, A. & V. Giavarini (2009) Thermutis Fr. (1825). Pp. 893-894 in Smith, C.W., A. Aptroot, B.J. Coppins, A. Fletcher, O.L. Gilbert, P.W. James & P.A. Wolseley (eds.). The Lichens of Great Britain and Ireland. The British Lichen Society, London.