Phialoparvum sinense H. Pan & Zhi. Y. Zhang, 2025

Pan, Heng, Tong, Shuo-Qiu, Chen, Zeng, Wu, Yun-Jie, Wang, Yi, Tao, Gang & Zhang, Zhi-Yuan, 2025, Two new acremonium-like species, Paragibellulopsis sinensis sp. nov. and Phialoparvum sinense sp. nov. (Sordariomycetes, Ascomycota) from China, MycoKeys 118, pp. 207-224 : 207-224

Phialoparvum sinense H. Pan & Zhi. Y. Zhang sp. nov.

Fig. 3

Type.

China • Guizhou Province, Guiyang City, Xiuwen County, Zhazuo Town, Guizhou Wildlife Park , 26.85°N, 106.69°E, soil, 25 May 2022, Zhi-Yuan Zhang (holotype HMAS 353384 , dried culture; culture ex-type CGMCC 3.27537 , ibid., ZY 22.078 ) .

Etymology.

The epithet “ sinense ” (Lat.) refers to China, where the species was collected.

Description.

Culture characteristics (14 days at 25 ° C): Colony on PDA 67–69 mm diam. white aluminum to grey-white from center to margin, flocculent, subcircular, margin regular; reverse: tele grey to grey-white from center to margin. Colony on OA 58–60 mm diam. white, flocculent, subcircular, margin regular; reverse: white. Colony on SNA 25–27 mm diam. white, flattened, hyphae sparse; reverse: white.

Mycelium consisting of branched, septate, hyaline, and smooth-walled hyphae, 1–3 μm wide. Conidiophores solitary, erect, arising directly from vegetative hyphae or ropes of hyphae, unbranched or poorly branched. Phialides lateral, terminal, subulate, hyaline, smooth-walled, 8.5–50.5 × 1–3 μm, with cylindrical collarette and conspicuous periclinal thickening at the conidiogenous locus; adelophialides sometimes present, up to 4 μm long; polyphialides with two conidiogenous loci are occasionally present. Conidia arranged in slimy heads, obovate with slightly obtuse base, sometimes cylindrical with slightly obtuse base, 1 - celled, hyaline, smooth-walled, 2–6.5 × 1–3 μm (av. 4.5 × 2, n = 50). Sexual morph undetermined.

Geographical distribution.

Guizhou Province, China.

Additional material examined.

China • Guizhou Province, Guiyang City, Xiuwen County, Zhazuo Town, Guizhou Wildlife Park , 26.85°N, 106.69°E, soil, 25 May 2022, Z. Y. Zhang, ZY 22.079, ibid., ZY 22.080, and ZY 22.081 .

Notes.

Phylogenetic analysis showed that four new isolates ( CGMCC 3.27537 , ZY 22.079, ZY 22.080, and ZY 22.081) clustered in a single subclade with high support values (100 / 1) and were nested in Phialoparvum s. str. (Fig. 1 ). Morphologically, Ph. sinense differs from other species in the genus Phialoparvum in that it produces obovate conidia and longer phialides ( Giraldo and Crous 2019; Giraldo et al. 2019). In addition, they can be distinguished by their low sequence similarities. In a comparison of ITS, LSU, rpb 2, and tef- 1 α nucleotides, Ph. sinense (ex-type CGMCC 3.27537 ) has 95.3 %, 97.2 %, 93.5 %, and 96.3 % similarity in ITS (469 / 492 bp, seven gaps), LSU (773 / 795 bp, four gaps), rpb 2 (262 / 280 bp, no gap), and tef- 1 α (758 / 787 bp, no gap), which is different from Ph. bifurcatum (ex-type CBS 299.70 B). In a comparison of ITS, LSU, and rpb 2 nucleotides, Ph. sinense ( CGMCC 3.27537 ) has 96.5 %, 98.1 %, and 91.9 % similarity in ITS (453 / 469 bp, four gaps), LSU (778 / 793 bp, no gap), and rpb 2 (751 / 817 bp, no gap), which is different from Ph. maaspleinense (ex-type CBS 145321 ). In a comparison of ITS, LSU, and rpb 2 nucleotides, Ph. sinense ( CGMCC 3.27537 ) has 96.6 %, 98.3 %, and 92.7 % similarity in ITS (483 / 500 bp, five gaps), LSU (780 / 793 bp, no gap), and rpb 2 (694 / 748 bp, no gap), which is different from Ph. rietveltiae (ex-type CBS 145322 ).

Figures

Figure 1. Phylogenetic tree inferred from a maximum likelihood analysis based on a concatenated alignment of ITS, LSU, rpb 2, and tef- 1 α sequences of 63 strains representing plectosphaerellaceous fungi and outgroups. The ML bootstrap support values (MLBS) above 70 % and Bayesian posterior probabilities (BPP) above 0.70 are given at the nodes (MLBS / BPP). Strains with special status are indicated with a superscript letter after the accession number (T: ex-type, ET: ex-epitype, IT: ex-isotype, NT: ex-neotype). The new species are printed in blue font. The tree is rooted to Monilochaetes infuscans CBS 869.66 and CBS 379.77.

Figure 3. Phialoparvum sinense (from holotype HMAS 353384) a – c upper and reverse views of cultures on PDA, OA, and SNA after 14 days at 25 ° C d, e monophialides and conidia f adelophialides and conidia g, h polyphialide and conidium. Scale bars: 10 μm (d – h).