Lecanora flavidofusca
Description : Thallus verrucose to verruculose, yellowish grey to greenish grey, epruinose. Soredia absent. Prothallus absent. Apothecia sessile, 0.5–1.0 mm diam., discs red-brown to dark-brown, epruinose. Margins concolorous with thallus, thin, smooth, entire. Cortex hyaline, 10–20 μm thick, inspersed with small crystals. Amphithecium with large crystals not dissolving in K, but also with abundant, small crystals rapidly dissolving in K (melacarpella -type). Parathecium hyaline, 15 μm thick, with crystals. Epithecium reddish brown with small crystals, pigments and crystals dissolving in K (pulicaris -type), c. 10–14 μm thick. Hypothecium hyaline. Paraphyses not thickened apically. Asci clavate, 45–65 × 10–15 μm. Ascospores ellipsoidal to broadly ellipsoidal, 11.5–17.5 × 5.5– 8.5 μm.
Chemistry : Thallus K+ yellow, C+ orange; major compounds: arthothelin, atranorin, usnic acid and zeorin; minor compounds: chloroatranorin, 2,5-dichlorolichexanthone, 4,5-dichloro-norlichexanthone and an unidentified terpene (Lumbsch et al. 1995: 567).
N: South Auckland (S of Te Aroha, Tauranga). On coastal shrubs. A corticolous lichen occurring on a wide variety of different phorophytes in high-light environments in tropical and subtropical regions. Known also from Central and South America, Papua New Guinea and Australia (Guderley 1999: 194; McCarthy 2003c, 2006; Lumbsch & Elix 2004; Ryan et al. 2004b: 217–218). The apothecial discs of L. flavidofusca vary from relatively dark brown to clear, red-brown, but are more commonly rather dark.
Pantropical
Illustrations : Lumbsch et al. (1995: 564, figs 5–6); Guderley (1999: 193, fig. 16A).
Lecanora flavidofusca is characterised by: the corticolous habit; the pulicaris -type epithecium; the absence of xanthones; the presence of zeorin; and the melacarpella -type amphithecium.
