Cytospora calamicola

Cytospora calamicola

Konta & K.D. Hyde (2023)

Classification:Ascomycota-Pezizomycotina-Sordariomycetes-Sordariomycetidae-Diaporthales-Cytosporaceae-Cytospora

Host species: Calamus sp. (Konta et al. 2023)

Holotype: MFLU 15-0262 (Konta et al. 2023)

Known distribution: Phang-Nga, Thailand

IF Number: IF559679     Mycobank Number: 559679     FOF Number: FoF10825

Description

Saprobic on dead petiole of Calamus sp. Sexual morph: Ascomata 260–380 × 185–290 μm, scattered, immersed, eventually with erumpent neck arising through cracks in bark epidermis, uniloculate, globose to sub-globose or irregular, whitish-yellow on the host surface, with long neck. Neck up to 120–250 μm long, central, lined with periphyses. Peridium 13–16 μm wide, comprising an outer layer of yellow to pale-brown, thick-walled cells of textura prismatica and inner layer, hyaline, thin-walled layer of cells. Paraphyses absent. Asci 15–20 × 3–5 μm, (x̅ = 16.5 × 5 μm, n = 50), 8-spored, unitunicate, cylindrical to clavate, with thin-walled pedicel, apex flat. Ascospores 3–5 × 1–2 μm, (x̅ = 4.3 × 1.7 μm, n = 100), biseriate or crowded, hyaline, fusiform or allantoid, oblong, unicellular, aseptate, smooth-walled (Fig. 11.11). Asexual morph: Coelomycetous. Conidiomata 250–300 × 110–175 μm, appearing as brownish-yellow areas, pycnidia semi-immersed, solitary or aggregated, globose to sub-globose, with long neck. Peridium 10–13 μm wide, comprising pale-brown, thick-walled, cells of textura epidermoidea. Conidiophores erect, hyaline. Conidiogenous cells enteroblastic, proliferating percurrently to produce small, hyaline, ellipsoidal conidia. Conidia 1–3 × 1–2 μm, (x̅ = 1.8 × 1.3 μm, n = 20), oblong to fusiform, small, unicellular, hyaline and smooth-walled.

Culture conditions: Colonies on MEA after ascospores and conidia germinated. Colonies from above; white to creamy, mycelia medium dense, circular, flat, entire margin. Colonies from below; yellow-white, circular with entire edge.

Cytospora calamicola (MFLU 15-0259). (A–C) Appearance of ascomata on host substrate. (D, E) Section of an ascoma. (F) Peridium. (G) Ostiolar neck. (H, I) Asci. (J) Ascospores. (K) Geminated ascospore. (L) Colony on MEA. Scale bars: A–C= 500 μm, D, E, G =100 μm, F = 20 μm, I = 5 μm, J, K = 2 μm.