Flabellascoma aquaticum

Flabellascoma aquaticum D.F. Bao, Z.L. Luo, K.D. Hyde & H.Y. Su

Index Fungorum number: IF 556720; Facesoffungi number: FoF 06212

Holotype: MFLU 19–0992

Etymology: Referring to the aquatic habitat

Saprobic on submerged decaying wood. Sexual morph: Ascomata 280–440 μm high, 260–390 μm diam (x̅ = 327 × 360 μm, n = 8), immersed, scattered, subglobose, dark brown to black, with a long, black neck. Ostiole crest-like, dark brown to black, elongated, composed of brown to black cells. Peridium 25–52 μm wide, uniform, comprising 2 zones, outer layers composed several dark brown cells, inner zone composed of 5–7 layers of rectangular, hyaline to pale brown cells of textura angularis and globulosa. Hamathecium comprising numerous, 1.2–2 μm wide, cellular pseudoparaphyses, septate, branched and anastomosed. Asci 48–72 × 8–9 μm (x̅ = 60 × 8.6 μm, n = 20), 8-spored, bitunicate, fissitunicate, cylindrical-clavate, short pedicellate, apically rounded with an ocular chamber. Ascospores 16–18 × 4.3–5.3 μm (x̅ = 17 × 5 μm, n = 30), fusiform with narrow and obtuse ends, hyaline, uniseptate, slightly constricted at the septum, 4-guttules, 2 middle ones larger than end ones, with a narrow sheath. Appendages drawn out from sheath at both of ends (4.7–7 μm wide, n = 30), hyaline, unbranched. Asexual morph: Undetermined. (Description from Bao et al. 2019)

Material examined: CHINA, Yunnan Province, saprobic on decaying wood submerged in Dulong River (27°53'51.50" N, 98°20'13.10" E), May 2015, Z.L. Luo, S-390 (MFLU 19–0992, holotype), ex-type living culture, KUMCC 15–0258.

Notes: Flabellascoma species have similar shaped asci and ascospores. F. cycadicola and F.

minimum are distinguishable from each other based on ascospore size. F. aquaticum differs from F. cycadicola in ascus and ascospore size (48–72 × 8–9 vs. 67.5–88 × 9–12 μm and 16–18 × 4.3–5.3 vs. 17–23 × 4.5–7 μm). Moreover, F. aquaticum can be morphologically distinguished from F. cycadicola and F. minimum based on ascomata characters. F. aquaticum has ascomata with a cylindrical, long, black neck. Whereas ascomata of F. cycadicola and F. minimum have short, elongated, crest-like, ostiolar neck. In the phylogenetic analysis, F. aquaticum and F. fusiforme grouped with other existing Flabellascoma species, but formed distinct lineages, and thus are distinct species. (Notes from Bao et al. 2019)

Freshwater Distribution: China (Bao et al. 2019)