Xanthopsoroma soccatum
Family
Pannariaceae
Flora category
Lichen – Native
Endemic taxon
No
Endemic genus
No
Endemic family
No
Structural class
Lichens - Squamulose
Current conservation status
2018 | Not Threatened | Qualifiers: SO
Brief description
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
Distribution
North Island: Northland to South Auckland (Waiotapu Valley), Wellington. South Island: 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). Stewart Island: (Port Pegasus).
Known also from New South Wales and Tasmania.
Habitat
Mainly West of Main Divide, reaching East coast near Dunedin (Maungatua). Epiphytic on trunks of Fuscospora, 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.
Detailed description
Thallus small, squamulose, often widely scattered, on a prominent black, thin, continuous, fibrous or byssoid prothallus, 3-5(-10) cm diam. Squamules small, ± discrete, 0.1-1.0 mm diam., round to irregular, plane to subconvex, rarely forming a continuous crust, ± consistently sorediate, especially at centre, esorediate near margins, sometimes forming a diffract-areolate, sorediate crust centrally, some squamules ascending, white tomentose below. Upper surface pale greenish or yellowish-white, smooth, waxy or matt, commonly with fine, silky, bristling crystals (×10 lens). Soredia white, or yellowish, granular, surrounded by a halo of white, silky crystals. Cephalodia common, scattered, between squamules on prothallus, never developing on squamules, simple, globose to glomerulate, smooth, purplish-brown. Apothecia not common, scattered, sessile or subpedicellate, 0.1-1.2 mm diam., round to irregular, disc dark red- brown to blackish, matt, epruinose, not gyrose-etched, sometimes ± sorediate, margins crenulate-striate, waxy, occasionally granular-sorediate, thalline exciple wrinkled-striate, ± sorediate. Ascospores 15-17 × 11 µm.
Chemistry: Dechloropannarin and usnic acid (visible as minute, silky, bristling crystals on surface – ×10 lens).
Similar taxa
Similar to Xanthopsoroma contextum but with soredia.
Substrate
Corticolous
Attribution
Fact sheet prepared by Marley Ford (5 December 2023). Brief description, Distribution, Habitat, Features and Similar taxa sections copied from Galloway (1985; 2007).
References and further reading
Galloway D.J. 1985: Flora of New Zealand: Lichens. Wellington: PD Hasselberg, Government Printer. 662 pp.
Galloway D.J. 2007: Flora of New Zealand: Lichens, including lichen-forming and lichenicolous fungi. 2nd edition. Lincoln, Manaaki Whenua Press. 2261 pp.