Alternaria scirpivora (E.G. Simmons & D.A. Johnson) Woudenb. & Crous, Studies in Mycology 75: 198 (2013)
MycoBank number: MB 803702; Index Fungorum number: IF 803702; Facesoffungi number: FoF 12792;
Basionym: Nimbya scirpivora E.G. Simmons & D.A. Johnson, Mycotaxon 84: 424. 2002.
Synonym: Macrospora scirpivora E.G. Simmons & D.A. Johnson, Mycotaxon 84: 422. 2002.
Saprobic on decaying, submerged twigs in freshwater habitats. Sexual morph: Ascomata 140–245 μm high, 110–290 diam. ( = 194 × 224 μm), solitary to clustered, superficial, subglobose or nearly globose, ovoid to probably cup-shaped when dry, dark brown to black, carbonaceous, with a blunt ostiole. Peridium 27.5–65.5 μm ( = 42 μm, n = 10) wide, outer layer composed of heavily pigmented, thick-walled cells of textura angularis, inner layer composed of lightly pigmented or hyaline, thin-walled cells of textura angularis. Hamathecium composed of 3–8 μm ( = 5 μm, n= 20) wide, cellular, septate, pseudoparaphyses branching and anastomosing above asci, longer than asci. Asci 143–237 × 42–56 μm ( = 176.5 × 48 μm, n = 20), 8-spored, bitunicate, fissitunicate, cylindrical to clavate, straight or slightly curved, with a short, furcate pedicel and minute ocular chamber. Ascospores 37–58 × 16–23 μm ( = 46 × 19 μm, n = 30), overlapping uni- to biseriate, muriform, initially subclavate to ellipsoid, when mature broadly obovoid or ellipsoid, 5-transseptate, constricted at the septa, with one central longitudinal septa, hyaline when young, pale yellowish brown at maturity, guttulate, smooth-walled. Asexual morph: Colonies effuse, hyaline, on the substratum superficial, hairy, velvety. Mycelium mostly immersed, consisting of branched, septate, smooth, hyaline hyphae. Conidiophores macronematous, mononematous, erect, solitary or in fascicles, pale brown, becoming paler towards the apex, 2–7-septate, branched, smooth-walled, cylindrical, 20–73.5 × 4–8.5 μm ( = 45 × 6 μm, n = 20). Conidiogenous cells polytretic, integrated, terminal or intercalary, determinate, subhyaline to pale brown, cylindrical. Conidia acropleurogenous, solitary, pale yellowish brown, obclavate, rostrate, straight, or slightly curved, up to 14-septate, tapering towards the rounded apex, truncate at the base, 43.5–152 × 8.5–16 μm ( = 109.5 × 12 μm, n = 20), 2–5.5 μm wide ( = 3.5 μm, n = 20) at the apex, constricted at the septa, smooth-walled.