Flora of New Zealand Series

Type : E. polycarpum Fée [=E. groendalianum (Ach.) Vain.]

Description : Thallus foliose, lobate, orbicular, rosette-forming to irregularly spreading, ±loosely attached. Upper surface distinctly felted–arachnoid, often with ±erect, shaggy tufts of tomentum, greyish-blue to malachite-green when moist. Photobiont cyanobacterial, Scytonema. Medulla white. Lower surface white with scattered ±squarrose bundles of blackish rhizohyphae. Ascomata apothecia, mostly marginal, disc plane, often becoming convex, pale pinkish to red-brown, with distinct, paler, proper exciple; thalline exciple absent; cyanobiont penetrating apothecium along subhymenium. Hymenium I+ blue. Asci with apical amyloid sheet-like structures. Ascospores ellipsoidal, ±smooth-walled. Conidiomata pycnidia, moderately common, marginal, immersed, black.

Erioderma, included in the family Pannariaceae (Eriksson et al. 2004; Pennycook & Galloway 2004), contains 31 species (Jørgensen 2003c, 2004e). Species of Erioderma are foliose and mostly orbicular, with thalli up to 15 cm diam.; lobes are normally hairy on the upper surface and have marginal to submarginal, rarely laminal apothecia with a special anatomy (Keuck 1977); asci are 8-spored with colourless, simple, thick-walled and usually subglobose ascospores; the lower surface is naked, rarely veined, and usually with bundles of blackish rhizohyphae, especially at the margins; a few species may have a continuous mat of rhizohyphae forming a spongy structure; the secondary chemistry comprises compounds of the pannarin group. Taxa are mainly tropical and are best developed and most highly speciose in the neotropics of South America and in SE Asia (Jørgensen 2001d, 2003c; Jørgensen & Arvidsson 2002; Jørgensen & Sipman 2002b), but extend as far south as Patagonia and north to Macaronesia, western Scandinavia, British Columbia and Newfoundland in strongly oceanic habitats. Two species recorded from New Zealand are characteristic of successional vegetation in humid habitats in moderate shade. For additional discussion see Keuck (1977), Galloway & Jørgensen (1975), Jørgensen & Galloway (1992b), Jørgensen (2001a, 2001d), Jørgensen & Arvidsson (2001, 2002), and Jørgensen & Sipman (2002b). Elix et al. (1986a) discuss chemistry of Erioderma.