TYPE. “In insulâ Rawak” (Gaudichaud-Beaupré 1827) [INDONESIA. Moluku Islands], 1817-1820, C. Gaudichaud s.n. (PC, holotype)

Description. Lichenized fungus.

Thallus foliose, closely to loosely adnate, up to 10 cm wide, 50-70 µm thick, matt, dark bluish gray to olivaceous. Lobes round to broadly oblong, 1-3 mm wide; margins entire, confluent; upper surface smooth, shiny, without isidia or phyllidia. Lower surface lighter than the upper surface, bluish to gray, smooth to slightly ridged, without hairs. Photobiont Nostoc cyanobacteria; cells in chains. Apothecia rare; laminal, sessile to shortly pedicellate, 0.5-1.5 mm wide; disk concave to flat, pale to dark red-brown; thalline rim smooth to wavy, upper most margin same as thallus color. Hymenium ~125 µm high; subhymenium hyaline, 30-40 µm thick; hypothecium hyaline, ~50 µm. Ascospores ellipsoid, ends obtuse, submuriform to muriform, 20-30 × 6-12 µm; pycnidia not seen.

Substrate and Habitat. Corticolous in forests.

Distribution. Neotropical, Australasian and east Asian; in North Carolina found in the Coastal Plain ecoregion.

Literature

Gaudichaud-Beaupré, C. (1827) Voyage autour du Monde, Entrepis par Ordre du Roi, Exécuté sur les Corvettes de S.M. l'Uranie et la Physicienne. Botanique (Nagpur). 5: 161-208 (original description as Thelephora molucca)

Jayalal U., S.H. Jang, N.H. Yu, S.O. Oh & J.S. Hur. (2014) Notes on the lichen genus Leptogium (Collemataceae, Ascomycota) in South Korea. Mycobiology. 2014 Jun;42(2):120-31.

Kitaura, M.J., N.M. Koch, F. Lucheta, M.I. Käffer, J.L. Schmitt, J. Pedroso, S.A. Martins, A.S. Rodrigues & L.S. Canêzi. (2019) A new species and new records of Leptogium (Ach.) Gray (Collemataceae, Peltigerales) from Rio Grande do Sul State with an identification key for the genus. Anais da Academia Brasileira de Ciências [Annals of the Brazilian Academy of Sciences] 91(1): e20180313, 1-26.