Physcia crispa
Description : Thallus irregularly spreading, loosely attached, 1–2 cm diam. Lobes thin, rather fragile, 1–2 mm wide, 2–3 mm long, crowded-imbricate. Margins irregularly notched or incised to crenulate, ascending, sinuous, slightly thickened-ridged below, minutely lobulate-isidiate becoming sorediate. Upper surface pale olivaceous green when moist, creamish green to very pale buff-green when dry, smooth to shallowly undulate, matt, sorediate, without maculae or pruina. Soralia developing from minute marginal lobules or isidia (×10 lens), soon becoming sorediate and eroding conspicuous areas of margins and lower surface, in places ±labriform, most conspicuous on inner parts of lobes and around sinuses separating lobes; soredia coarsely granular, olivaceous-white. Lower surface corticate, white to ivory, darkening to pale-tan centrally, smooth to minutely wrinkled or pitted, rhizinate. Rhizines widely scattered, rather sparse, concolorous with lower surface, simple, with an apical squarrose tuft, 0.5–1 mm long. Apothecia and pycnidia not seen.
Chemistry : Cortex K+ yellow; medulla K−; containing atranorin.
N: Northland (Cavalli Is, Poor Knights Is, Hen and Chickens Is), Wellington (Kitchener Park Feilding, Levin). On bark in northern, coastal forest. Known also from East Africa (Moberg 1986b; Swinscow & Krog 1988), North America (Harris 1990; 1995; Esslinger & Egan 1995; Brodo et al. 2001; Moberg 2002b), South America (Aptroot 1989b; Moberg 1990; Scutari 1995b; Marcano et al. 1996; Calvelo & Liberatore 2001), Hongkong (Aptroot & Seaward 1999), the Pacific Islands (Elix & McCarthy 1998 – as Physcia albicans) and Australia (Moberg 2001; McCarthy 2003c, 2006).
Palaeotropical
Physcia crispa is characterised by: the corticolous habit; the thin, fragile, undulate lobes; the marginal soralia developing from minute marginal lobules or isidia; and the K− reaction of the medulla. Nomenclature of this species is discussed in Moberg (1986b: 855).
