Lecanora elixii
Description : Thallus crustose, uniform, adnate, thin to very thin, of continuous to dispersed verrucae; yellow-white to yellow-grey, or grey-white, epruinose, lumpy–areolate, sometimes reduced to small areas surrounding apothecia; soredia absent; margins indefinite; prothallus not developed, 1–3(–4) cm diam. Apothecia crowded, sessile, 0.3–0.9 mm diam., disc grey-brown to bluish grey pruinose. Cortex distinct at base, hyaline ±gelatinous, slightly inspersed with small crystals, 15–20 μm laterally and 20–40 μm at base. Amphithecium with small crystals (polarising filter +), crystals rapidly dissolving in K (campestris -type). Parathecium hyaline, without crystals (polarising filter –), 10–15 μm thick. Epithecium reddish brown, pigments completely dissolving in K, with crystals on epihymenium (chlarotera -type). Hymenium hyaline, 65–75 μm tall. Hypothecium and subhymenium hyaline. Paraphyses 1.5 μm thick, septate, apically slightly ramifying but not thickened. Asci clavate 50–65 × 10–14 μm. Ascospores broadly ellipsoidal, 8.5–12.5 × 5.5–7.5 μm.
Chemistry : Thallus and apothecia margins K+ yellow, C+ orange, KC+ orange, Pd+ yellowish orange; containing atranorin, 5,7-dichloro-3- O- methylnorlichexanthone, isoarthothelin, 3- O- methylasemone, and 2,5,7-trichloro-3- O- methylnorlichenxanthone (major) and arthothelin, asemone, chloroatranorin, 2,7-dichloronorlichexanthone, 5,7-dichloronorlichexanthone and 2,5,7-trichlorolichexanthone as minor compounds.
S: Canterbury (Banks Peninsula, Long Spur, Lynn Stream, Mt Peel). On subalpine rocks, 600–1100 m and on seashore rocks. Still poorly collected and understood in New Zealand. Also in temperate SE Australia (Lumbsch 1994; Lumbsch & Feige 1994; McCarthy 2003c, 2006; Lumbsch & Elix 2004).
Australasian
Illustrations : Lumbsch (1994: 84, fig. 57C–D); Lumbsch et al. (1994a: 33, fig. 1A).
Lecanora elixii is characterised by: the presence of the 2,5,7-trichloro-3- O- methylnorlichexanthone chemosyndrome; relatively small, broadly ellipsoidal spores, a reduced thallus and pruinose apothecial discs (Lumbsch 1994; Lumbsch & Feige 1994; Lumbsch et al. 1994a). It is very closely related to L. lugubris (q.v.) and may in fact just be a saxicolous form of that species, though there are slight chemical and anatomical differences between the two taxa.
