Tubeufia eccentrica Y.Z. Lu, J.C. Kang & K.D. Hyde
Index Fungorum number: IF 554901; Facesoffungi number: FoF 04756
Etymology: “eccentrica” referring to conidia attached conidiogenous cells eccentrically.
Holotype: HKAS 97439
Saprobic on decaying wood in a freshwater stream. Sexual morph Undetermined. Asexual morph Hyphomycetous, helicosporous. Colonies on the substratum superficial, effuse, gregarious, hyaline to white. Mycelium composed of partly immersed, partly superficial, hyaline to pale brown, septate, abundantly branched hyphae, with masses of crowded, glistening conidia. Conidiophores macronematous, mononematous, flexuous, cylindrical, occasionally branched, septate, 30–80 μm long, 5–6 μm wide, hyaline to pale brown, smooth-walled. Conidiogenous cells holoblastic, mono- to polyblastic, integrated, sympodial, intercalary or terminal, cylindrical, repeatedly geniculate, truncate at apex after conidial secession, 20–30 μm long, 4–5 μm wide, hyaline to pale brown, smooth-walled. Conidia solitary, acropleurogenous, helicoid, attached eccentrically and seceding schizolytically, rounded at tip, 70–80 μm diam. and conidial filament 6–8 μm wide (x̄ = 75 × 7 μm, n = 20), 400–570 μm long, coiled 1½–2½ times, becoming loosely coiled in water, 52–62-septate, guttulate, hyaline. (Lu et al. 2018)
Culture characteristics: Conidia germinating on water agar and germ tubes produced from conidia within 12 h. Colonies growing on PDA, circular, with flat surface, edge entire, reaching 29 mm in 3 weeks at 28 °C, pale brown to brown in PDA medium. Mycelium superficial and partially immersed, branched, septate, hyaline to pale brown, smooth.
Material examined: CHINA, Guangxi Province, Fangchenggang City, on submerged decaying wood in a freshwater stream, 14 May 2016, Yong-Zhong Lu, PF03 (HKAS 97439, holotype; GZAAS 16–0094, isotype), ex-type living culture, MFLUCC 17–1524 = GZCC 16–0082; Ibid., PF08–1 (GZAAS 16–0096, paratype), living culture, GZCC 16–0084; CHINA, Guangxi Province, Fangchenggang City, on submerged decaying wood in a freshwater stream, 15 May 2016, Yong-Zhong Lu, JHC05–2 (GZAAS 16–0047, paratype), living culture, GZCC 16–0035; Ibid., JHC16–1 (GZAAS 16–0060, paratype), living culture, GZCC 16–0048.
Notes: Tubeufia eccentrica resembles T. inaequalis and T. guangxiense in conidiophores and conidia but can be distinguished by their conidial size. The conidial diameter of T. eccentrica (70–80 μm) is larger than T. inaequalis (45–60 μm) and T. guangxiense (45–70 μm). Phylogenetically, four isolates of T. eccentrica form a monotypic clade and share a sister relationship to T. guangxiense with good bootstrap support, and support that they are distinct species (Lu et al. 2018).
Freshwater distribution: China (Lu et al. 2018)