Nalanthamala xishuangbannaensis H. Zheng & Z. F. Yu, 2024

Zheng, Hua, Dai, Xinwen, Li, Haiyan & Yu, Zefen, 2024, Two new species of Nectriaceae (Hypocreales, Sordariomycetes) from Yunnan, China, MycoKeys 108, pp. 269-285 : 269-285

Nalanthamala xishuangbannaensis H. Zheng & Z. F. Yu sp. nov.

Fig. 3

Etymology.

Named after the location Xishuangbanna, where the holotype was collected.

Type.

China • Yunnan province, Xishuangbanna Dai Autonomous Prefecture; isolated from air in forest; Apr 2017; Z. F. Yu, preserved by lyophilization (a metabolically inactive state) in State Key Laboratory for Conservation and Utilization of Bio-Resources in Yunnan ( YMF 1.05062 , holotype); ex-type living culture: CGMCC 3.27596 .

Description.

Sexual morph not observed. Asexual morph on CMA. Hyphae 1.5–3.5 μm wide, hyaline, septate, smooth-walled, branched. Conidiophores hyaline, dimorphic, acremonium-like or penicillium-like. Acremonium - like conidiophores unbranched; phialides cylindrical or slightly tapering toward the tip, straight to slightly bent, 18–37 μm long or longer, 2.3–3.2 μm wide at base, and 1.2–2 μm wide at tip. Penicillium-like conidiophores solitary to aggregated; stipe hyaline, smooth, subcylindrical, septate, 20–80 μm long or longer, up to 3 μm wide at the base; primary and secondary branches subcylindrical, hyaline, smooth, aseptate, 8–16.8 × 2.3–3 µm; phialides cylindrical, flask-shaped, 12.3–22.2 × 2.7–3.2 μm. Conidia either obovate, with an obtuse tip and a truncated base, typically held in long and dry chains, 4–4.8 × 3–3.8 μm or ellipsoidal, cylindrical, or fusiform, with obtuse ends, or with an obtuse tip and a visible, slightly laterally displaced hilum, 4.4–6 × 2.7–3.5 μm. Chlamydospores not observed.

Culture characteristics.

Colonies growing on PDA and CMA after 3 days of incubation at 28 ° C. Colony on PDA rapid-growing, surface dusty to fine powdery, white to iron gray due to occurrence of conidial masses, reverse white, aerial hyphae flocculent, reaching 53–57 mm diam., indistinct margin. Colony on CMA thin, surface white, reverse translucent, aerial hyphae sparsely developed, reaching 35–37 mm diam.

Additional materials examined.

China • Yunnan province, Xishuangbanna Dai Autonomous Prefecture ; isolated from air in forest; Apr 2017; Z. F. Yu; living cultures B 413 , B 425 .

Notes.

Morphologically, Nalanthamala xishuangbannaensis fits well with the generic concepts of Nalanthamala in having acremonium-like or penicillium-like conidiophores and oval or lenticular conidia arranged in chains ( Schroers et al. 2005). In the phylogenetic analysis, the three newly obtained strains ( YMF 1.05062, B 413 and B 425) clustered together in a single clade with a strong statistical support (BP / BS = 1.00 / 100), and the clade was closely related to N. diospyri and N. psidii (Fig. 1 ). N. xishuangbannaensis can be distinguished from N. diospyri by its wider obovate conidia (3–3.8 μm vs. 2.5 μm in width) and shorter ellipsoidal, cylindrical or fusiform conidia (4.4–6 μm vs. 8–12 μm in length) ( Schroers et al. 2005). In a comparison of ITS, LSU and tub 2 sequences, N. xishuangbannaensis (type strain YMF 1.05062) has 95 % (469 / 496 bp, 5 gaps), 97 % (691 / 709 bp, 2 gaps) and 91 % (294 / 323 bp, 3 gaps) similarity to N. diospyri ( CBS 430.89), respectively. In addition, N. xishuangbannaensis differs from N. psidii in smaller and wider obovate conidia (4–4.8 × 3–3.8 μm vs. 4.5–5.1 × 2.4–2.7 μm) and shorter and wider ellipsoidal, cylindrical or fusiform conidia (4.4–6 × 2.7–3.5 μm vs. 6–11 × 1.7–2.8 μm) ( Schroers et al. 2005). Sequences of N. xishuangbannaensis (type strain YMF 1.05062) have 96 % similarity in ITS (471 / 493 bp, 5 gaps) and tub 2 (329 / 351 bp, 4 gaps) to N. psidii ( CBS 687.97).

Figures

Figure 1. Phylogenetic tree inferred from a Maximum likelihood analysis based on a concatenated alignment of ITS, LSU, rpb 2 and tub 2 sequences of some representing species in Nectriaceae. The Bayesian posterior probabilities (BP) ≥ 0.9 and RAxML bootstrap support values (BS) ≥ 75 % were shown at the nodes (BP / BS). Strains obtained in this study are shown in blue font. Ex-type strains are marked by a T after the strain number. The tree was rooted to Sarocladium summerbellii (CBS 430.70).

Figure 3. Nalanthamala xishuangbannaensis (YMF 1.05062, holotype) A colony on PDA after 3 days of inoculation at 28 ° C B colony on CMA after 3 days of inoculation at 28 ° C C conidia arranged in long chains under low power microscopy D, E acremonium-like conidiophores F – H penicillate conidiophores I conidia. Scale bars: 1.0 cm (A, B); 50 µm (C); 10 µm (D – I).