Flora of New Zealand Series

Description : Thallus dispersed, verrucose to granular–papillate or verruculose, effuse, whitish grey to yellowish grey, with or without a sparse, grey pruina. Soredia absent. Prothallus whitish grey to lacking. Apothecia scattered to crowded centrally, sessile to constricted at base, 0.6 –1.3 mm diam., discs bright red-brown to grey-brown, matt, occasionally bluish grey- to whitish grey-pruinose. Margins prominent, concolorous with thallus, entire, thin to thick, smooth or ±verrucose to crenulate. Cortex hyaline, gelatinous, inspersed with small crystals, 15–25 μm laterally and 20–55 μm basally. Amphithecium with large crystals not dissolving in K (pulicaris -type). Epithecium 10–15 μm thick, brown to yellow-brown, pigments dissolving in K, with small crystals (chlarotera -type). Hymenium colourless, 65–85 μm tall. Hypothecium colourless. Asci 45–60 × 10–15 μm. Ascospores broadly ellipsoidal, 11–15 × 5–7 μm.

Chemistry : Thallus and apothecial margin: K+ yellow, C−, KC−, Pd + yellow-orange; containing as major compounds: chloroatranorin and zeorin; and as minor compounds: atranorin and an unidentified triterpenoid, and depside (Lumbsch 1994: 92).

S: Canterbury (Omihi State Forest, Three Mile Bush Road), Otago (Inch Clutha). A distinctive corticolous species occuring on introduced trees and shrubs (Carmichaelia, Salix) along roadsides and riverbeds and on waste ground. Associating with species of Candelariella, Haematomma, Lecidella, Physcia, Ramalina. Known also from dry to semi-arid habitats in Mexico, Central and South America and Australia (Lumbsch 1994; Guderley 1999: 195; McCarthy 2003c, 2006; Lumbsch & Elix 2004; Ryan et al. 2004b: 218).

?Pantropical

Illustrations : Lumbsch (1994: 90, fig. 58C–F); Lumbsch et al. (1995: 568, fig. 7); Guderley (1999: 193, fig. 16B).

Lecanora flavomarginata is characterised by: the corticolous habit; the bluish- to whitish-grey-pruinose discs; and the broadly ellipsoidal ascospores. The species is discussed by Lumbsch (1994: 92–93), Lumbsch et al. (1995: 567–568), Guderley (1999: 194–195) and Lumbsch & Elix (2004: 32–33).