Tubeufia brevis Y.Z. Lu, J.C. Kang & K.D. Hyde
Index Fungorum number: IF 554897; Facesoffungi number: FoF 04751
Etymology: “brevis” referring to short conidiophores of this fungus.
Holotype: MFLU 17–1099
Saprobic on decaying wood in a freshwater stream. Sexual morph Undetermined. Asexual morph Hyphomycetous, helicosporous. Colonies on the substratum superficial, effuse, gregarious, 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, branched, septate, 30–60 μm long, 3.5–5 μm wide, pale brown, smooth-walled. Conidiogenous cells holoblastic, mono- to polyblastic, integrated, sympodial, terminal, cylindrical, truncate at apex after conidial secession, 12–24 μm long, 3.5–4.5 μm wide, pale brown, smooth-walled. Conidia solitary, acropleurogenous, helicoid, rounded at tip, 38–45 μm diam. and conidial filament 4–5 μm wide (x̄ = 40 × 4.5 μm, n = 50), 245–305 μm long, tightly coiled 2½–3¼ times, becoming loosely coiled in water, indistinctly multi-septate, guttulate, hyaline, smooth-walled.
Culture characteristics: Conidia germinating on water agar and germ tubes produced from conidia within 48 h. Colonies growing on PDA, circular, with flat surface, edge entire, reaching 27 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: THAILAND, Chiang Rai, Muang, Ban Nang Lae Nai, on submerged decaying wood in a freshwater stream, 31 December 2016, Yong-Zhong Lu, CR15 (MFLU 17–1099, holotype), ex-type living cultures, MFLUCC 17–1799, TBRC.
Notes: Tubeufia brevis is characterized by short irregular branched conidiophores with tightly helicoid conidia which become loose in water. Tubeufia brevis resembles T. dentophora in conidiophore and conidial morphology but can be recognized by its wider conidial filaments (4–5 μm vs. 2.5–3.5 μm). Our multi-gene phylogenetic result shows that T. brevis is a distinct species despite the lack of support to other species (Lu et al. 2018).
Freshwater distribution: Thailand (Lu et al. 2018)