Flora of New Zealand Series

Description : Flora (1985: 480–481).

Chemistry : Dechloropannarin and usnic acid (visible as minute, silky, bristling crystals on surface – ×10 lens).

N: Northland to South Auckland (Waiotapu Valley), Wellington. S: Nelson (Mt Arthur), Marlborough (Pelorus Bridge), Westland (Mt Brewster), Canterbury (Arthur's Pass, Black Birch Stream, Glencoe Stream Mt Cook), Otago (Lake Ohau, Makarora, Maungatua), Southland (Dusky Sound). St: (Port Pegasus). Mainly W of Main Divide, reaching E coast near Dunedin (Maungatua). Epiphytic on trunks of Nothofagus, Leptospermum and Griselinia, and other trees and shrubs less commonly – also among mosses in rock crevices. In deep shade squamules are fewer and more scattered on a better-developed black prothallus. It tolerates deep shade, but is also common at forest margins in moderate to high-light. Known also from New South Wales and Tasmania (Jørgensen & Galloway 1992b: 287; McCarthy 2003c, 2006) and southern South America (Galloway & Quilhot 1999).

Austral

Illustrations : Jørgensen & Galloway (1992b: 286, fig. 98D); Kantvilas & Jarman (1999: 133).

Psoroma soccatum is characterised by: the corticolous habit; the squamulose thallus developed on a prominent, black, continuous fibrous to byssoid prothallus; thalline squamules small, 0.1–1.0 mm diam., round to irregular, scattered, rarely forming a continuous crust, consistently sorediate, upper surface pale greenish or yellowish (usnic acid), smooth, waxy or matt, with fine, silky, bristling crystals (×10 lens); cephalodia globose to glomerulate, purplish brown, scattered between thalline squamules on prothallus; apothecia rare, 0.1–1.2 mm diam., disc dark red-brown to blackish, margins waxy, crenulate-striate, occasionally granular-sorediate; and ellipsoidal ascospores, 15–17 × 8–11 μm.