Tubeufia chiangmaiensis Boonmee & K.D. Hyde, Fungal Diversity 68: 248 (2014)
Index Fungorum number: IF 550705; MycoBank number: MB 550705; Facesoffungi number: FoF 00172; Figs. 1, 2
Saprobic on decaying wood. Sexual morph Ascomata 227.5–253 × 160–192 µm, superficial, seated on a subiculum, solitary, scattered, globose-subglobose to ovate, cream-white to yellowish when freshly, light brown to brown, collapsing when dry, slightly compressed subiculum hyphae, developing from ascomatal base onto substrate, with ambiguous ostiolate. Peridium 13–22.5 µm wide, composed of 2–3 layers of thick-walled, light brown cells of textura angularis. Hamathecium comprising 1–2 µm wide, numerous, septate, branched, hyaline pseudoparaphyses. Asci 116–123×12–15.5 µm (x̅=118.5×14 µm, n=10), 8-spored, bitunicate, fissitunicate, elongate cylindrical to slightly clavate, apedicellate, thick-walled, rounded at apex, tapering towards narrow base, sessile. Asci 54.5–70×3.5–5.5 µm (x̅=63×5 µm, n=10), overlapping 2–3-seriate, cylindric-fusiform, tapering toward ends, 7-septate, slightly constricted at the medium septum, hyaline, smooth-walled. Asexual morph Hyphomycetous, helicosporous. Conidiophores semi-macronematous, mononematous, borne as lateral branches from superficial hyphae, pale brown to brown, septate, simple or branched, flexuous to geniculate. Conidiophores cells holoblastic, terminal or intercalary, dentate, hyaline, smooth. Conidia 26–54 µm diam., conidial filament 4–6(–9) µm wide, (186–)265–309.5 µm long, loosely coiled 1–2½ times, becoming loosely uncoiled in water, rounded at apical ends, indistinctly multi-septate, not constricted at the septa, hyaline to brown, with granular contents.
Culture characteristics – Ascospore germinating on MEA within 24 h and many germ tubes produced from many cells. Colonies growing on MEA, reaching greater than 10 mm diam. in 7 days at room temperature, flat, sparsely hairy, radially striate, with fimbriate edge, dark brown, with yellowish pigmented in the medium after 30 days. Mycelium superficial, composed of branched, septate, brown to dark brown hyphal filaments, conidial spores formed on hyphae in culture at 60 days.
Material examined – THAILAND, Chiang Mai Province, Mae Taeng, Pa Pae, Mushroom Research Center, on decaying wood, 17 July 2015, S. Boonmee, MRC2 (MFLU 21-0103, new record), living culture, MFLUCC 16-0197.
GenBank numbers – ITS=MZ538530, LSU=MZ538564, TEF1-α=MZ567105.
Notes – Tubeufia chiangmaiensis was collected from Mushroom Research Center, Chiang Mai Province, Thailand. This is the third report for T. chiangmaiensis produced an asexual morph on culture (Fig. 3). Our isolate MFLUCC 16-0197 shares some similar morphological characters of sexual and asexual morphs (Figs. 1 and 2) to the type of T. chiangmaiensis MFLUCC 15-0514 and MFLUCC 17-01801 (Boonmee et al. 2014; Lu et al. 2018b). However, no outstanding differences were observed in the morphological comparison among three isolates . Therefore, a record of T. chiangmaiensis on decaying wood, from Chiang Mai Province is reported.
Figure 1 – Tubeufia chiangmaiensis (MFLU 21-0103, new record). a Superficial ascomata on decaying wood substrate. b Squash mount of ascoma showing peridium and subiculum hyphae at the base. c Pseudoparaphyses. d–f Asci. g–i Ascospores. Scale bars: a=200 µm, b=100 µm, c=10 µm, d–f=50 µm, g–i=20 µm
Figure 2 – Tubeufia chiangmaiensis sporulation in culture (MFLUCC 16-0197). a Germinated ascospore. b, c Culture on MEA from surface and reverse after 1 month. d–f Development of conidia and mycelium in culture. g–j Conidia. Scale bars: a, f=50 µm, d=100 µm, e=10 µm, g–j=20 µm
Figure 3 – Maximum likelihood phylogenetic tree based on a combined LSU, ITS and TEF1-α sequence dataset of Tubeufia taxa and related genera in Tubeufiaceae. Eighty-four strains are included in the combined analyses which comprise a total of 2395 characters. Pseudohelicomyces talbotii (MFLUCC 17-2021) is selected as the outgroup taxon. The best RAxML tree with a final likelihood value of − 11543.960875 is presented. RAxML analysis yielded 680 distinct alignment patterns and 15.58% of undetermined characters or gaps. Estimated base frequencies were as follows: A=0.238955, C=0.251270, G=0.256785, T=0.229079, with substitution rates AC=0.670086, AG=4.164732, AT=3.398524, CG=0.528840, CT=7.628422, GT=1.000000; gamma distribution shape parameter alpha=0.148685. Bootstrap support values for maximum likelihood (MLBS, left) equal to or greater than 70% is given above the nodes. Bayesian posterior probabilities (BYPP, right) equal to or greater than 0.95 are given above the nodes. Ex-type strains are in bold and newly generated sequences are in blue