Flora of New Zealand Series

Holotype: New Zealand. Nelson, Upper Cobb Valley, headwaters of Burgoo Stream, c. 1180 m, 1983, J.K. Bartlett 26690 – AK.

Description : Thallus crustose, closely attached to substratum, smooth to warty, yellowish brown to brown, with a white pruina, 0.1–0.5 mm thick, 3–10 cm diam, prothallus brown, distinct to indistinct. Ascomata perithecioid to lirelliform, solitary or rarely united, aggregated into distinctly elevated, stroma-like structures, slightly to distinctly constricted at base, 0.8–1.9 mm diam., usually with more than 10 ascomata. Hypothecium extending down to substratum or fusing with dark-yellow to brownish medulla, hard and black. Excipulum 5–15 μm thick. Hymenium 100–120 μm tall, with oil droplets and granules. Paraphysoids 1–2 μm diam., sparsely branched. Asci 80–90 × 10–14 μm. Ascospores obovate, hyaline, 3-septate (44–)47–53(–57) × 3–4 μm. Conidiomata pycnidia, few to numerous, dispersed evenly over thallus, solitary. Conidia filiform, curved (11–)12–15(–16) × 1 μm.

Chemistry : Roccellic acid and yellow pigments (secalonic acid derivatives).

N: Wellington (Northern Ruahine, Otupai Ra.). S: Nelson (Upper Cobb Valley). On shaded subalpine to alpine rocks, 100–1180 m. Also in Tasmania (Kantvilas & Thor 1993; McCarthy 2003c, 2006).

Australasian

Illustration : Thor (1990: 51, fig. 34).

Chiodecton montanum is characterised by: the saxicolous habit, oil droplets and granules in the hymenium, and yellow pigments (secalonic acid derivatives and skyrin) in the medulla.