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

Fig. 3

Etymology.

“ yinggelingensis ” refers to the type locality, “Yinggeling National Nature Reserve”.

Holotype.

HKAS 128856 .

Description.

Saprobic on submerged decaying wood in a freshwater habitat. Asexual morph Hyphomycetous, helicosporous. Colonies on natural substrate superficial, effuse, gregarious, with crowded, glistening conidia, white. Mycelium partly superficial, composed of hyaline to pale brown, branched, septate, guttulate, smooth hyphae. Conidiophores 21.5–143 × 4.5–7 μm (x ̄ = 67.5 × 5.5 μm, n = 25), macronematous, mononematous, erect, cylindrical, flexuous, branched, septate, pale brown to brown, thick-walled. Conidiogenous cells 9–15 × 4–5 μm (x ̄ = 11.5 × 4.5 μm, n = 20), holoblastic, monoblastic, integrated, terminal, cylindrical, with denticles, pale brown to brown, smooth-walled. Conidia solitary, acrogenous, helicoid, rounded at apex, developing on tooth-like protrusion, 22–31 μm diam. and conidial filament 4–6 μm wide (x ̄ = 27 × 5 μm, n = 20), 148–170 μm long (x ̄ = 157.5 μm, n = 20), tightly coiled 2 3 / 5 –3 1 / 4 times, not becoming loose in water, indistinctly multi-septate, guttulate, hyaline, smooth-walled. Sexual morph Undetermined.

Culture characteristics.

Conidia germinated on PDA and formed germ tubes after 11 hours of incubation. Colonies on PDA are irregular with a flat surface and undulating margin, reaching 3.2 cm in diameter after 39 days at room temperature (approximately 25 ° C), and are brown to dark brown in color.

Material examined.

China • Hainan Province, Yinggeling National Nature Reserve , on rotting wood in a freshwater stream, 12 July 2022, Jian Ma, YG 5 ( HKAS 128856 , holotype), ex-type living culture GZCC 23-0525 ; Ibid., YG 5-2 ( GZAAS 24-0080 , paratype), living culture GZCC 24-0166 .

Notes.

Morphologically, Tubeufia yinggelingensis ( HKAS 128856 ) closely resembles T. denticulata ( HKAS 131090 ) in having macronematous, mononematous, erect, cylindrical, branched, septate conidiophores; holoblastic, monoblastic, integrated, cylindrical conidiogenous cells; and solitary, hyaline, guttulate, helicoid conidia ( Ma et al. 2024). However, Tubeufia yinggelingensis ( HKAS 128856 ) differs from T. denticulata ( HKAS 131090 ) by its unique conidiogenous cells (terminal vs. intercalary) and larger conidia (22–31 μm diam. and conidial filament 4–6 μm wide, 148–170 μm long vs. 19–21 μm diam. and conidial filament 2–4 μm wide, 73.5–142.5 μm long) ( Ma et al. 2024). Based on molecular phylogenetic analyses, Tubeufia yinggelingensis ( GZCC 23-0525 and GZCC 24-0166 ) formed a sister clade with T. yanuodaensis ( GZCC 23-0488 and GZCC 24-0165 ), which is phylogenetically distinct from T. denticulata ( CGMCC 3.25583) (Fig. 1 ). Thus, based on morphological comparison and multigene phylogenetic analysis, we identified GZCC 23-0525 and GZCC 24-0166 as a new species, Tubeufia yinggelingensis .

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 3. Tubeufia yinggelingensis (HKAS 128856, holotype). a, b. Colonies on the host surface; c – f. Conidiophores and conidiogenous cells; g – i. Conidiogenous cells and conidia; k – p. Conidia; j. Germinated conidium; q, r. Colonies on PDA, q from above, r from below. Scale bars: 50 μm (c, d); 40 μm (e, f); 10 μm (g – p).