Macentina stigonemoides
Description : Thallus pale-green, filamentous, minutely fruticose, 50–400(–600) μm tall, densely branched; here and there disintegrating into soredia-like granules; granules 15–40 μm diam., superficial cells often prominent and with one or more papillae. Branches 12–25 μm diam., ±prostrate or more commonly ascending, cylindrical; cortical cells with papillae c. 1 μm tall. Perithecia 200–380 μm diam., pale-brown, ovoid or ±obpyriform. Exciple 30–80 μm thick, the median layer of elongated cells, the outer layer of isodiametric cells. Ascospores 3- to (4–)5-septate, (13–)16–21 × (4–)5–6 μm.
S: Southland (Invercargill, Thomson's Bush). On shaded trunk of Coprosma angustifolia, among mosses and other crustose lichens. Known also from the United Kingdom, France, Sweden and Madeira (Orange 1989a; Arup & Ekman 1992; Kalb & Hafellner 1992; Santesson 1993; Henssen 1995a; Santesson et al. 2004).
?Cosmopolitan
Illustrations : Orange (1989a: 230, fig. 1A–E; 231, fig. 2A–E; 232, fig. 3).
Macentina stigonemoides is characterised by: the corticolous habit; the cylindrical, papillose branches of the minutely fruticose, filamentous thallus – these are often sterile and easily mistaken for an alga or for moss protonemata. Sterile granular forms have bulging, papillose cells on the surface of the granules, and often also short lengths of branches intermixed with the granules (Orange 1992a). Henssen (1995: 203) placed M. stigonemoides in the genus Psoroglaena Müll.Arg.
