TYPE. SPAIN. Canary Islands, on trunk. Anonymous s.n. (FI-WEBB, lectotype designated by Galloway & Jørgensen 1995).
Description. Lichenized fungus.
Thallus foliose, orbicular, 1-5 cm wide, dark green when wet, grayish black when dry, membranous, wrinkled. Lobes ridged, erect, swollen. Vegetative diaspores isidia, brownish gray, darker than thallus, short, densely clustered, mostly on thalline ridges. Lower surface rugose, uneven, lacking tomentum. Photobiont Nostoc cyanobacteria; cells in chains. Ascomata lecanorine apothecia, rare, on lobe margins; disk concave to flat, reddish; margin thin, granulose. Ascospores hyaline, transversely septate, fusiform-acicular, 40-65 x 3-8 μm.
Substrate and Habitat. On deciduous trees and mossy rocks.
Distribution. Cosmopolitan; in North Carolina found in the Blue Ridge ecoregion.
Notes.Leptogium brebissonii has been found to comprise a species complex (i.e., representing multiple closely related but distinct species) through molecular analysis (Kaasalainen et al. 2021).
Literature
Barker-Webb, P. & S. Berthelot. (1840) Histoire naturelle des Iles Canaries. 3 (original description).
Gilbert, O.L. & P.M. Jørgensen. (2009) Leptogium (Ach.) Gray (1821). Pp. 541-551 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.
Kaasalainen, U., V. Tuovinen, P.M. Kirika, N.P. Mollel, A. Hemp & J. Rikkinen. (2021) Diversity of Leptogium (Collemataceae, Ascomycota) in East African Montane Ecosystems. Microorganisms9: 314.
Swinscow, T.D.V. & H. Krog. (1988) Macrolichens of East Africa. British Museum (Natural History), London. 390 pp.