Lepraria incana
≡Byssus incana L., Sp. Pl. 2: 1169 (1753). [Typification is discussed in Laundon (1992: 334–335) and Jørgensen et al. (1994a: 271).]
Description : Flora (1985: 245)
Chemistry : Thallus K− or rarely + yellow or + violet-red, C−, KC− or rarely + violet-red, Pd− or rarely + orange; containing divaricatic acid and zeorin (Kümmerling & Leuckert 1991; Lohtander 1994: 229) with gyrophoric acid and atranorin in trace amounts. Leuckert et al. (1995: 247) record also the following accessory compounds: nordivaricatic acid, divaric acid, divaricatinic acid and lecanoric acid.
N: Northland (Lat. 35ºS) to Wellington. S: Nelson (Lake Rotoroa) to Southland (Lake Hauroko). St: (Glory Cove). On bark, clay banks, soil in rock crevices or beneath rock overhangs, or on rocks (both acidic and basic). Although mainly lowland and coastal (tree-fern caudices are a favoured substratum) it is known from some subalpine habitats to 1600 m, east of the Main Divide. In shaded, forest sites specimens are glaucous-green and granular–floccose, spreading irregularly over the substratum, while in exposed habitats on rock, thalli may become ±placodioid at margins forming ±concentric rings, dying centrally. Known also from Great Britain, Scandinavia, northern Europe, the United States, South Africa, South America and SE Australia (Kümmerling et al. 1991: 515; Laundon 1992: 335; Lohtander 1994; Filson 1996; Brodo et al. 2001; Kukwa 2002a; McCarthy 2003c, 2006; Nimis & Martellos 2003; Santesson et al. 2004; Tønsberg 2004b).
Cosmopolitan
Illustrations : Moberg & Holmåsen (1982: 220); Phillips (1987: 164); Dobson (1992: 185; 2000: 211; 2005: 242); Wirth (1995b: 538, 541); Sérusiaux et al. (2004: 90).
Lepraria incana is characterised by: the terricolous habit; the dull greenish grey, bluish-tinged thallus; undifferentiated medulla; and the presence of divaricatic acid and zeorin.
