Falciformispora aquatica

Falciformispora aquatica D.F. Bao, K.D. Hyde & H.Y. Su

Index Fungorum number: IF 555415; Facesoffungi number: FoF 05059

Etymology: Referring to the aquatic habitat of this fungus

Holotype: MFLU 18-1228

Saprobic on decaying wood, submerged wood in freshwater. Asexual morph Undetermined. Sexual morph: Ascomata 260–330 μm diam. 230–300 μm high (x̄ = 286 × 260 μm, n = 10) solitary to gregarious, immersed in the host tissue, globose to subglobose, coriaceous, papillate, ostiolate, dark grey to black. Peridium up to 25–30 μm wide, composed of outer thick-walled angular or rounded greyish brown cells, and inner hyaline cells of textura prismatica. Hamathecium comprising 2–3.5 μm wide, numerous, septate, cellular pseudoparaphyses, hyaline, branched, surrounded by a gelatinous matrix. Asci 115–167 × 28–47 μm (x̄ = 147 × 36 μm, n = 20), 8-spored, bitunicate, fissitunicate, cylindro-clavate, short pedicellate. Ascospores 48–59 × 10–16 μm (x̄ = 55 × 13 μm, n = 30), fusiform to clavate, hyaline, straight or slightly curved, 5–6-septate, mostly 6-septate, slightly constricted at all septa, tapering to narrow both of ends, surrounded by a mucilaginous sheath and a single scythe-like appendage at the apex. (Descriptions from Hyde et al. 2019)

Culture characteristics: Ascospores germinating on PDA within 24 h. Colonies on MEA at room temperature reaching 2.5 cm diam. in three weeks, mycelium pale brown to grayish brown after 3 weeks, composed brown to dark brown, septate, smooth or verrucose hyphae. (Descriptions from Hyde et al. 2019)

Material examined: THAILAND, Prachuap Khiri Khan Province, Sai Khu Waterfall, on submerged decaying wood, August 2017, Vinit Kumar., site1–2–1, (MFLU 18–1228, holotype), ex-type living culture (MFLUCC 18–0212).

Notes: The phylogenetic analyses showed that Falciformispora aquatica grouped with members of Falciformispora but separated in an independent lineage with relatively high bootstrap support (100% ML/1.00 BYPP). Falciformispora aquatica is similar to F. lignatilis, as they have similar asci (bitunicate, fissitunicate, with a short pedicel) and ascospores (fusiform to clavate, hyaline). However F. aquatica has larger asci (115–167 × 28–47 vs. 110–136 × 20–32 μm), and larger ascospores (48–59 × 10–16 vs. 42–50 × 7.5–10 μm). Moreover, F. aquatica ascospores are mostly 6-septate, whereas those of F. lignatilis over 7-septate. (Descriptions from Hyde et al. 2019)

Freshwater distribution: Thailand (Hyde et al. 2019)