Asteronia sweetiae Henn., Hedwigia 34: 104 (1895) Fig. 23
= Parodiopsis sweetiae (Henn.) G. Arnaud, Annls Épiphyt. 7: 53 (1921)
MycoBank number: MB 229114; Index Fungorum number: IF 229114; Facesoffungi number: FoF 06215
Parasitic or pathogenic on living leaves of Sweetia sp. Sexual morph: Colonies forming darkened regions on the underside of leaves, similar to a “sooty mold”. Ascomata 74–92 µm high × 67–74 µm diam., gregarious, solitary or some scattered, superficial, globose, subglobose to ovate, subcoriaceous, brown to black–brown, with an indistinct ostiole. Peridium 30–36 µm wide, comprising one layer of black-brown isodiametric cells of textura angularis. Hamathecium not apparent. Asci 60–93 µm × 20–27 µm ( x = 72 × 23 µm), 8-spored, bitunicate, oblong to broadly cylindrical, with a short indistinct pedicellate or sometime sessile, 8–9 µm long, 6.5–7.5 µm wide, apically rounded and thickened, with an indistinct ocular chamber. Ascospores 33–46 µm × 4–6.5 µm ( x = 41 × 5 µm), tri to multi-seriate, guttulate, thin-walled, straight or slightly curved, fusoid- ellipsoidal, widest in the middle part of the apical cell, with broadly rounded apex and tapering to a narrowly rounded base, hyaline, 1-septate, septum nearly central but nearer to apex, rough-walled. Asexual morph: Undetermined.
Material examined – BRAZIL, Estado de Minas Gerais, on leaves of Sweetia sp. (Fabaceae), June 1892, E. Ulé (S-F46114, isotype).
Economic significance – The genus Asteronia is associated with dead and living leaves of mostly tropical plants and comprised pathogens, saprobes or epiphytes (Boonmee et al. 2017).
Figure 23 – Asteronia sweetiae (S-F46114, isotype). a, b Details of herbarium material. c, d Habit and appearance of ascomata on host surface. e Section of ascomata. f Peridium. g–i Asci. j, k Ascospores. Scale bars: c = 1 mm, d = 200 µm, e = 50 µm, f–i = 20 µm, j, k = 10 µm.