Flora of New Zealand Series

≡Sticta argyracea Delise, Mém. Soc. linn. Calvados [Normandie] 2: 91, pl.7, fig. 30 (1825).

Description : Thallus ±rosette-forming, orbicular, 1–5(–10) cm diam., corticolous or saxicolous, closely attached to bark or rocks, loosely attached and ±free when on twigs or among mosses. Lobes irregularly laciniate to broadly rounded, 3–10(–20) mm diam., 1–3 cm long, ±discrete to imbricate. Margins sinuous, often slightly revolute and very slightly ridged below, entire or minutely crenate-incised, usually delicately isidiate. Upper surface livid grey-blue or grey-black, very minutely mottled (×10 lens) when moist, pale olivaceous-grey to red-brown when dry, plane, undulate or minutely and irregularly wrinkled, smooth or minutely roughened, fragile, sorediate and isidiate, without maculae or phyllidia. Pseudocyphellae laminal, scattered, punctiform, becoming sorediate, to 3 mm diam., ulcerose, round to irregular, flat to convex, soredia white, coarsely granular. Pseudoisidia minute, styliform, terete, simple to coralloid, at first clustered at margins of pseudocyphellae and at apices and margins of lobes, in some specimens spreading more widely to form a diffract-coralloid crust, dark brown, mainly corticate, rarely sorediate below or occasionally forming expanded and flattened regenerating lobules. Medulla white. Photobiont Nostoc. Lower surface pale fawnish or pinkish white, shallowly wrinkled or pitted, ±densely tomentose from centre to margins, tomentum whitish, silky, entangled, rather shaggy. Pseudocyphellae very rare or absent, minute, white, punctiform, best seen near margins. Apothecia not seen.

Chemistry : 7β-acetoxyhopane-22-ol, hopane-7β, 22-diol (tr.), hopane-15α,22-diol, methyl gyrophorate and gyrophoric acid (C+ pink, fleeting).

N: South Auckland (Pureora). S: Nelson (Lake Rotoiti to Lewis Pass), Westland (Grey River), Marlborough (Stephens I., Kaikoura), Canterbury (Alford Forest, Mt Peel), Otago (Hampden, Flagstaff). St: [map in Galloway (1988a: 67, fig. 20)]. In medium- to low-light habitats, on rocks, among bryophytes and ferns, and on trunks of forest trees and shrubs, including Dracophyllum, Kunzea ericoides, Melicytus ramiflorus and Nothofagus solandri var. cliffortioides. Known also from E Africa, India, Thailand Japan, the palaeotropics, southern South America, E Australia and Tasmania (Galloway 1988a: 64–66; 1992c, 1994b: 117, fig. 1; Galloway et al. 2001b; Wolseley et al. 2002; McCarthy 2003c, 2006).

Palaeotropical

Illustrations : Delise (1825a: pl. 7, fig. 30 – as Sticta argyracea); Galloway & James (1986: 450–451, fig. 7B); Galloway (1988a: 65, fig. 19); Kantvilas & Jarman (1999: 5, 112).

Pseudocyphellaria argyracea is characterised by: the corticolous habit; a white medulla, a cyanobacterial photobiont; scattered, laminal, white pseudocyphellae; and clustered pseudoisidia developed at lobe apices and margins, and around margins of laminal pseudocyphellae.