Tubeufia yanuodaensis X. Y. Ma, J. Ma & Y. Z. Lu, 2025

Ma, Xiao-Yan, Tian, Fu, Feng, Jiang-Fen, Wang, Min-Min, Shi, Huan-Huan & Ma, Jian, 2025, Morphological and phylogenetic analyses reveal two new species of Tubeufia (Tubeufiales, Tubeufiaceae) from freshwater habitats in China, MycoKeys 121, pp. 93-109 : 93-109

Tubeufia yanuodaensis X. Y. Ma, J. Ma & Y. Z. Lu sp. nov.

Fig. 2

Etymology.

“ yanuodaensis ” refers to the type locality, “Yanuoda Rainforest Cultural Tourist District”.

Holotype.

HKAS 128924 .

Description.

Saprobic on submerged decaying wood in a freshwater habitat. Asexual morph Hyphomycetous, helicosporous. Colonies on natural substrate superficial, effuse, white to pale brown. Mycelium partly superficial, composed of hyaline to pale brown, branched, septate, smooth hyphae. Conidiophores 64–83 × 6–7 μm (x ̄ = 71.5 × 6.5 μm, n = 20), macronematous, mononematous, erect, cylindrical, straight or slightly flexuous, branched, septate, subhyaline to pale brown, thick-walled. Conidiogenous cells 13.5–16 × 3–5 μm (x ̄ = 14.5 × 4 μm, n = 20), holoblastic, monoblastic, integrated, subcylindrical, terminal, truncate at apex after conidial secession, subhyaline to pale brown, smooth-walled. Conidia solitary, acrogenous, helicoid, 35.5–40 μm diam., and conidial filament 4.5–5 μm wide (x ̄ = 37.5 × 4.8 μm, n = 20), 252–338 μm long (x ̄ = 291 μm, n = 25), tightly coiled 3 1 / 4 –3 4 / 5 times, becoming loosely coiled in water, multi-septate, slightly constricted at septa, guttulate, hyaline, smooth-walled. Sexual morph Undetermined.

Culture characteristics.

Conidia germinated on PDA and produced germ tubes within 9 h. Colonies on PDA are irregular with a flat surface and undulating margin, reaching 2.5 cm in diameter after 30 days at room temperature (approximately 25 ° C), and are pale brown to dark brown.

Material examined.

China • Hainan Province, Baoting Li and Miao Autonomous County, Yanuoda Rainforest Cultural Tourist District , on submerged decaying wood in a freshwater stream, 23 October 2021, Jian Ma, Y 2 ( HKAS 128924 , holotype), ex-type living culture GZCC 23-0488 ; Ibid., Y 2-2 ( GZAAS 24-0079 , paratype), living culture GZCC 24-0165 .

Notes.

In the present phylogenetic analysis, Tubeufia yanuodaensis ( GZCC 23-0488 and GZCC 24-0165 ) formed a sister lineage to T. yinggelingensis ( GZCC 23-0525 and GZCC 24-0166 ) with 100 % ML and 1.00 BYPP statistical support (Fig. 1 ). Based on the molecular sequence comparison, our isolate ( GZCC 23-0488 , ex-type) differs from T. yinggelingensis ( GZCC 23-0525 , ex-type) by 71 / 857 bp for ITS (8.3 %, gaps 42 bp), 7 / 833 bp (0.8 %, gap one bp) for LSU, 20 / 892 bp (2.2 %, without gaps) for tef 1-α, and 45 / 767 bp (5.9 %, gaps 3 bp) for rpb 2. Morphologically, Tubeufia yanuodaensis ( HKAS 128924 ) can be distinguished from T. yinggelingensis ( HKAS 128856 ) by its larger conidia (35.5–40 μm diameter and 252–338 μm long vs. 22–31 μm diameter and 148–170 μm long). Therefore, Tubeufia yanuodaensis is introduced here as a new species based on molecular evidence and morphological comparison.

Figures

Figure 1. Phylogenetic tree generated from the ML analysis based on a combined dataset of LSU, ITS, tef 1 - α, and rpb 2 sequence data. Bootstrap support values from ML analyses ≥ 75 % and Bayesian posterior probabilities (BYPP) ≥ 0.95 are indicated at the nodes as ML / BYPP, respectively. The ML and BI analyses yielded similar tree topologies. The tree is rooted with Acanthohelicospora aurea GZCC 16-0060 and A. guianensis UAMH 1699. The newly obtained strains are indicated in bold black. Ex-type strains are denoted with “ T ”.

Figure 2. Tubeufia yanuodaensis (HKAS 128924, holotype). a, b. Colonies on the host surface; c. Conidiophores and conidiogenous cells; d – h. Conidia; i. Germinated conidium; j, k. Colonies on PDA, j from above, k from below. Scale bars: 40 μm (c, d); 30 μm (e); 20 μm (f – i).