Lecanora interjecta
Description : Thallus lumpy in congested warts or hummocks, yellowish grey to greenish grey, without soredia or marginal prothallus. Apothecia sessile, 0.3–0.8(–1) mm diam., crowded, congested, when young almost gyalectiform; thalline margin persistent, thick, entire or warted, concolorous with thallus; disc pinkish brown, yellow-brown, to red-brown, plane, epruinose. Amphithecium with large crystals not dissolving in K (pulicaris -type). Parathecium hyaline, with crystals, 15 μm thick. Epithecium reddish brown with crystals, pigments and crystals dissolving in K (pulicaris -type), 10–15 μm thick. Hymenium colourless. Spores ellipsoidal to broadly ellipsoidal, (10.5–)12–14 × 8–10 μm.
Chemistry : Thallus K+ yellow, C+ orange. Arthothelin, usnic acid (major); atranorin, chloroatranorin, 2,5-dichloronorlichexanthone and 4,5-dichloronorlichexanthone (minor).
N: Northland (Whangarei). On bark of Pseudopanax arboreus. Still very poorly collected and understood in New Zealand (Galloway et al. 2001: 32–33). In Australia it is known from tropical rainforest and mangroves in northern New South Wales, Queensland and the Northern Territory (Lumbsch et al. 1995; McCarthy 2003c, 2006; Lumbsch & Elix 2004).
Australasian
Illustrations : Lumbsch et al. (1995: 568, figs 11–12).
Lecanora interjecta is characterised by: the corticolous thallus; the presence of arthothelin (C+ orange); the pulicaris -type epithecium; the red-brown apothecial discs; and a chemistry of usnic acid, atranorin and xanthones (see above). It is distinguished from L. queenslandica on chemical and spore characters, L. queenslandica having smaller spores and containing psoromic acid.
