Chlamydotubeufia krabiensis

Chlamydotubeufia krabiensis Y.Z. Lu, Boonmee & K.D. Hyde

Index Fungorum number: IF552931; Facesoffungi number: FoF 03106

Etymology: ‘krabiensis’ referring to the place of collection.

Holotype: MFLU 17-0332

Saprobic on woody substrata in a freshwater stream. Sexual morph: Ascomata 232–261 high × 174–207 μm diameter (x̄ = 250 × 187 μm, n = 10), superficial, solitary or scattered, globose to subglobose, black, with a central ostiole. Setae 39–59 × 4–6 μm, covering the whole ascoma, dark brown to black, unbranched, thick-walled. Peridium 22–29 μm thick, composed of several layers of cells of textura angularis. Hamathecium 1–2 μm wide, branched, hyaline pseudoparaphyses. Asci 88–145 × 14–16 μm (x̄ = 109 × 15 μm, n = 20), 8-spored, bitunicate, fissitunicate, cylindrical to clavate or saccate, apically rounded, short pedicellate. Ascospores 27–42 × 5–7 μm (x̄ = 35.5 × 6 μm, n = 50), fusiform, hyaline, slightly curved, tapering toward the ends, guttulate, 6–7-septate, not constricted at the septa. Asexual morph: Hyphomycetous. Chlamydospores 70–94 μm long, 37–57.5 μm wide (x̄ = 84 × 49.5 μm, n = 20), blastic, intercalary, broadly oval to ellipsoid, dictyoseptate, slightly constricted at septa, smooth, darkened to black. (Hyde et al. 2017)

Culture characteristics: Ascospores germinating on water agar (WA) within 12 h and germ tubes produced from ascospores. Colonies growing slowly on malt extract agar (MEA), circular, with flat surface, veined and without wrinkles, edge undulate, reaching 11 mm in 3 weeks at 28 °C, brown to dark brown in MEA media. Mycelium superficial and partially immersed, branched, septate, hyaline to pale brown, becoming dark brown due to the development of chlamydospores.

Material examined: THAILAND, Krabi, Plai Praya, Khao To, Ban Bang Thao Mae, on decaying wood in a freshwater stream, 17 December 2015, S. Boonmee, BTM05–1 (MFLU 17-0332, holotype; GZAAS 17-0001, isotype), ex-type living cultures MFLUCC 16-1134, GZCC 17-0001.

GenBank numbers: ITS:KY678767; LSU:KY678759; TEF1:KY792598.

Notes: Chlamydotubeufia krabiensis was found on submerged wood from southern Thailand. The combined ITS, LSU and TEF1 sequence analysis confirm C. krabiensis as a new taxon that is basal to C. chlamydosporum and the type species C. huaikangplaensis with strong support (1.00 PP and 100% BS). The topology shows that they are phylogenetically distinct species (Hyde et al. 2017). We also compared C. krabiensis with C. huaikangplaensis by using single gene data, and there are 15, 6 and 22 bp differences in ITS, LSU and TEF1 respectively, which also confirmed that they are distinct species. Morphologically, C. krabiensis differs from C. huaikangplaensis by its lager ascomata and asci (Boonmee et al. 2011). Its chlamydospores are also larger than C. chlamydosporum 53–76.8 (–94) × 32–43.2 (–50.4) μm (Shearer 1987).