Flora of New Zealand Series

≡*Thrombium lecanorae Stein in F. Cohn, Kryptogamenflora von Schlesien 2: 329 (1879).

Description : Lichenicolous, parasymbiontic on thalli and apothecia of Lecanora dispersa, forming scattered, globose, black ascomata. Pseudothecia in groups of 2–6, ⅓–½ immersed in host, pyriform to obpyriform to ±globose, (70–)90–170(–200) μm diam., excipular wall dark-pigmented, uniformly 10–25 μm thick, slightly thickened (25–30 μm) around ostiole, formed of 4–6 layers of thick-walled, short-celled hyphae, pigmented dark-brown. Hymenium colourless, to 50 μm tall. Periphyses absent. Paraphysoids persistent, branched and anastomosing, colourless, 1.5–2 μm thick. Asci functionally fissitunicate, with a small ocular chamber, 8-spored, (50–)70(–100 × (12–)16(–21) μm. Ascospores simple, rarely 1-septate, colourless, oval, with a perispore when young, wall verruculose, (11–)12.5–19.5(–20.5) × (5.5–)6–8.5(–10) μm.

S: Canterbury (Mt Palm, Lowry Peaks Ra.). On calcareous rocks in grassland (Hoffmann & Hafellner (2000: 129). Known also from Great Britain, Europe, Scandinavia and Australia (Hoffmann & Hafellner 2000: 127–129).

Cosmopolitan

Host : On Lecanora flotoviana. Known also from Lecanora albescens, L. crenulata, and L. pruinosa (Hoffmann & Hafellner 2000: 125, 127–129).

Illustration : Hoffmann & Hafellner (2000: 131, fig. 34).

* Zwackhiomyces lecanorae is characterised by: the lichenicolous habit; scattered, immersed groups of pseudothecia on thalli and apothecia of species of Lecanora; simple to 1-septate, colourless ascospores, (11–)12.5–19.5(–20.5) × (5.5–)6–8.5(–10) μm, with a perispore when young and a verruculose wall.