Aureobasidium melanogenum (Herm-Nijh.) Zalar, Gostinčar & Gunde-Cim.

Basionym – Aureobasidium pullulans var. melanogenum Herm.-Nijh. [as ‘melanigenum‘]

Classification – Saccotheciaceae, Dothideales, Dothideomycetes, Ascomycota

Index Fungorum number – IF 807698; Facesoffungi number – FoF 00098

Other useful webpages – outlineoffungi.org; fungalgenera.org; Dothideomycetes.org

Description – Saprobic on Khaya senegalensis. Sexual morph: Ascostromata 600–800 μm high × 500–800 μm diam. (av. 710 × 662 μm, n = 10), dark brown to black, semi-immersed on host tissue, solitary, scattered, globose to subglobose, carbonaceous. Peridium 40–170 μm diam. (av. 115 μm, n = 30) μm, thick-walled, comprised of an inner layer of hyaline cells and an outer layer of brown cells of textura angularis. Hamathecium unbranched 1–4 μm diam. (av. 3 μm, n = 30), longer than asci. Asci 150–200 × 5–10 μm (av. 180 × 10 μm, n = 30), 8-spored, unitunicate, cylindrical, rounded at the apex, with an ocular chamber. Ascospores 20–40 × 5–10 μm (av. 30 × 7 μm, n = 30), overlapping uniseriate, 1–3 septate, constricted at the septum, fusiform to ellipsoid, gradually tapering towards the apex, containing up to four refractive oil globules. Asexual morph: undetermined.

Culture characteristics – Colonies on PDA reaching up to 80 mm in 14 days at 25 °C, smooth, flat, cream-colored from above and below, rounded margins.

Material examined – China, Guangdong Province, Guangzhou City, Haizhu District, Zhongkai University of Agriculture Engineering, 23°6′32″ N, 113°16′37″ E, alt. 20 m, on the bark of Khaya senegalensis (Desr.) A. Juss. (Meliaceae), 27 July 2021, YH. Yang & CF. Liao (ZHKU 21-0099, new host record), living culture ZHKUCC 21-0109, ZHKUCC 21-0110, ZHKUCC 21-0111.

GenBank accession numbers – LSU: OL621897, OL621898, OL621899; ITS: OL584325, OL584327, OL584326.

Notes – See Manawasinghe et al. (2022).

Aureobasidium melanogenum (ZHKU 21-0099, new host record). a–c Appearance of ascomata on dead wood. d Section through an ascoma. e Peridium. f Hamathecium. g–j Asci. k–p Ascospores. Scale bars: d–j = 50 μm, k–p = 20 μm.

Phylogram generated from RAxML analysis based on combined ITS and LSU sequence data for Aureobasidium melanogenum. The tree is rooted to Sydowia polyspora (CBS 544.95). Maximum likelihood bootstrap support values equal to or greater 50% and Bayesian posterior probabilities equal to or greater 0.95 are shown near the nodes (ML/BYPP). Ex–type/ ex–epitype strains are in bold. New isolates from South China fungi are in red.