TYPE. POLAND. Giant Mountains; “wächst an nackter Rinde der Fichten (Abies excelsa) in der Nähe des Zachenfalls im Riesengebirge (Fw.)” (Flotow 1850).

Description. Life form: lichenized fungus.

Thallus crustose, granular or areolate-subsquamulose; areoles ~0.1-0.4 mm diam., sometimes producing marginal, isidia-like granules, 0.05-0.1 mm diam., dark brown to green-brown (green when wet), matt, often with paler or white margins. Cortex absent, but cartilaginous layer present. Photobiont chlorococcoid alga; cells 8-17 × 8-12 µm, globose or broadly ellipsoid. Ascomata lecideine apothecia, sessile, the base distinctly constricted, round, sessile; disk concave to flat, black; margin prominent, thick, smooth. Exciple pseudoparenchymatous, or radiating hyphae, outer part dark red-brown, inner part paler. Epithecium dark brown; hymenium hyaline, I+ blue; paraphyses to 2.5 µm, simple or forked, straight, terminal cells with swollen apices 4-7 µm wide with dark brown pigmented caps to 10 µm tall; hypothecium brown-black, K–. Asci 1-spored, ellipsoid to clavate-cylindrical, thick walled, the outer layer K/I+ blue, without a distinct apical dome, with a thin K/I+ dark blue zone between the ascus wall and ascus contents in the ascus apex. Ascospores strongly muriform, oblong-ellipsoid, colourless or pale yellow-brown, 70-115 x 20-47 µm. Conidiomata not seen.

Chemistry. Spot tests negative; no substances detected by TLC.

Substrate and Habitat. Corticolous on mossy, acid-barked trees in humid forests.

Distribution. Circumpolar in cool temperate and boreal regions; in North Carolina found in the Blue Ridge ecoregion.

Literature

Flotow, J. von (1850) Lichenologische Beiträge zur Flora Europaea. Botanische Zeitung (Berlin) 8: 537-542, 553-559, 569-575 (original description as Heterothecium pezizoideum β disciforme).

Gilbert, O.L. & O.W. Purvis. (2009) Lopdaium Körb. (1855). Pp. 563-564 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.

Nimis P.L. (2023). ITALIC - The Information System on Italian Lichens. Version 7.0. University of Trieste, Dept. of Biology, (https://dryades.units.it/italic), accessed on 2023-03-18.