Neptunomyces chinensis Tennakoon & S. Hongsanan, 2025

Neptunomyces chinensis Tennakoon & S. Hongsanan , sp. nov.

Fig. 9 View Figure 9

Etymology.

Named after the country ( China) where this fungus was collected.

Holotype.

SZU 25-020 .

Description.

Saprobic on dead leaf of Phragmites australis ( Poaceae ). Sexual morph: Undetermined. Asexual morph: Coelomycetous. Conidiomata 90–110 × 80–150 µm ( x ̄ = 102 × 120 µm, n = 10), pycnidial, immersed to semi-immersed, dark brown to black, solitary to aggregated, globose to sub-globose, visible as dots on host surface. Conidiomatal wall 15–20 μm wide ( x ̄ = 16 µm), thick-walled, composed of several layers of brown to dark brown pseudoparenchymatous cells, fusing at the outside indistinguishable from the host tissues. Conidiophores reduced to conidiogenous cells. Conidiogenous cells 4–7 × 3–4 µm ( x ̄ = 4.8 × 3.5 µm, n = 20), discrete, hyaline, globose to doliiform, holoblastic. Conidia 6.5–8 × 4–5 ( x ̄ = 6.8 × 4.5 µm, n = 40) µm, hyaline to pale brown, ellipsoidal to limoniform, apex acute to apiculate, widest in the middle, tapering towards a narrowly truncate base, guttulate, smooth-walled.

Material examined.

China • Guangdong Province, Shenzhen , on a dead leaf of Phragmites australis ( Poaceae ), 20 December 2024, D. S. Tennakoon, SZD 12 ( SZU 25-020 , holotype), ex-type living culture, MBSZU 25-028 • ibid. 23 December 2024, SZD 15 ( SZU 25-021 , paratype), living culture, MBSZU 25-029 .

Notes.

According to the multi-gene phylogeny, our collection ( SZU 25-020 and SZU 25-021 ) constitutes an independent lineage sister to Neptunomyces juncicola (CPC 45436) with robust statistical support (97 % ML, 1.00 BYPP). In addition, new isolates cluster together with strong support (100 % ML, 1.00 BYPP). Our collection can be distinguished from N. juncicola by conidial characteristics; N. juncicola has subcylindrical to fusoid-ellipsoid conidia with sub-obtuse apex, whereas our collection has ellipsoidal to limoniform conidia with acute to apiculate apex ( Crous et al. 2024). Our collection differs from N. juncicola by having smaller conidiomata (90–110 × 80–150 µm vs 180–220 µm). However, SZU 25-020 and SZU 25-021 have some morphological similarities with N. soli (immersed to semi-immersed, globose to sub-globose conidiomata and doliiform conidiogenous cells and hyaline to pale brown conidia), but differ by conidia sizes (6.5–8 × 4–5 µm vs 5–6.5 × 3–5 µm) ( Yasanthika et al. 2024). In addition, a comparison of the 587 nucleotides across the ITS (+ 5.8 S) gene region of our collection ( SZU 25-020 ) and N. soli ( MFLUCC 24-0272 ) shows 19 base pair differences (3.23 %). Therefore, based on both morphological and phylogenetic evidence, we introduce our collection as a new species, N. chinensis , from China.