Phialophora chinensis Ya L. Li, de Hoog & R. Y. Li

Senwanna, Chanokned, Kumla, Jaturong, Kodchasee, Pratthana, Duangkon, Nutchanan & Suwannarach, Nakarin, 2025, Additions of New Endolichenic Fungi to Herpotrichiellaceae (Chaetothyriales, Ascomycota) from northern Thailand, MycoKeys 120, pp. 193-229 : 193-229

Phialophora chinensis Ya L. Li, de Hoog & R. Y. Li , in Li, Xiao, de Hoog Wang, Wan, Yu, Liu & Li, Persoonia 38: 11 (2016)

Fig. 3

Cultural characteristics.

Colonies on different agar media were incubated in the dark at 25 ° C for 1 months; colonies flat, irregular, with edge entire, velvety; on PDA (39 to 44 mm in diameter) surface grayish brown, dark brown to black at the margin, reverse olivaceous black; on MEA surface Blackish Grey, black at the margin, reverse olivaceous black; on MEA (49 to 53 mm in diameter) surface Blackish Grey, black at the margin, reverse olivaceous black; on OA (69 to 74 mm in diameter) surface grayish brown, reverse olivaceous black; on PCA (46 to 55 mm in diameter) surface and reverse grayish brown, dark brown at the margin, reverse olivaceous black, sporulation absent; on CMD (42 to 50 mm in diameter) surface and reverse brownish gray; and on CMA (33 to 41 mm in diameter) surface and reverse brownish grey, sporulation absent. Asexual morph in vitro dematiaceous hyphomycetes. Hyphae 1–3.4 µm wide, subhyaline to light brown, simple to branched, septate, smooth-, thin-walled, coiling, anastomosis observed. Conidiophores (4 –) 5.5–31 (– 45.3) × (2 –) 3–4.3 (– 4.8) µm (x ̄ = 17 × 3.6, n = 55), micro- or semi-macronematous, straight, simples or poorly branched, septate, slightly constricted at septa, smooth; micronematous conidiophores consisting in conidiogenous cells growing directly from vegetative hyphae, lateral or terminal. Phialides 4–11 (– 15.5) × 2.3–4 (– 5) µm (x ̄ = 8.3 × 3.3, n = 75), regularly flask-shaped to elongate-ampulliform or subulate, with an apical conspicuous collarette; collarettes (1.6 –) 2–3.9 (– 4.8) × (1.6 –) 2–3.9 (– 4.2) µm (x ̄ = 3 × 3, n = 65), usually funnel-shaped, darker than the rest of the phialide. Conidia 2–4 (– 5) × 1.6–2.7 (– 3.9) µm (x ̄ = 3.3 × 2.2, n = 75), hyaline to subhyaline, mostly broadly ellipsoidal, more rarely obovoidal, smooth-walled. Chlamydospores 9.5–20 (– 23) µm wide, abundantly produced in aerial hyphae, mostly intercalary, solitary or in branched chains, sub globose to ellipsoidal or barrel-shaped, pigmented, light to dark brown, smooth-, thick-, dark-walled, without or one-septate, constricted near the septa. Sexual morph unknown.

Cardinal temperatures for growth on MEA after two weeks

(mm). Optimum at the range of 25 ° C to 30 ° C (19 to 24), maximum 35 ° C (17 to 19). No growth 4 ° C.

Materials examined.

Thailand • Chiang Mai Province: Mueang Chiang Mai District, Suthep Subdistrict , endolichenic from the medulla of foliose lichen ( Parmotrema sp. ) on unidentified tree trunk, 18°48'27"N, 98°56'37.7"E, elevation 343 m, 26 June 2023, C. Senwanna, living culture: LC 10-10 = SDBR-CMU 504 , LC 10-11 = SDBR-CMU 505 , and LC 10-17 = SDBR-CMU 506 .

Ecology and distribution.

Endolichenic fungi from the medulla of foliose lichen ( Parmotrema sp. ) in Thailand (this study); pathogenic as chromoblastomycosis in human in China and Mexico ( Li et al. 2017; Ahmed et al. 2021), as fungal keratitis in India and USA ( Ply et al. 2023; Mitra et al. 2024), as phaeohyphomycosis in France ( Pruvot et al. 2023); saprobic from bamboo in China, from the environment in Japan, from plant materials in Brazil and China, and soil in China and from wheat straw in Brazil ( Li et al. 2017).

Notes.

A BLASTn search using ITS and tub 2 sequence data in NCBI has revealed sequence similarities of 98.98–99.83 % and 98.46–99.78 % between our strains ( SDBR-CMU 504 , SDBR-CMU 505 , and SDBR-CMU 506 ) and Phialophora chinensis strains. While the closest matches using the LSU sequence are P. ellipsoidea (strain MUCL 9768 ; AF 050282 ) with 99.89 % similarity (identities = 885 / 886, no gap), P. macrospora (strain MUCL 15541 ; EU 514701 ), and P. americana (strain UAMH 10872 ; EU 514691 ) with 99.77 % similarity (identities = 864 / 866, no gap). The closest matches using the SSU sequence are Capronia semiimmersa (strain UAMH 10872 ; JN 941209 ) with 99.71 % similarity (identities = 1018 / 1021, 1 gap), P. verrucosa (strain AFTOL-ID 670 ; EF 413614 ) with 99.60 % similarity (identities = 992 / 996, 2 gaps), and P. americana (strain CBS 840.69; AY 554291 ) with 99.33 % similarity (identities = 1033 / 1040, 4 gaps).

In our multigene phylogenetic study, strains SDBR-CMU 504 , SDBR-CMU 505 , and SDBR-CMU 506 form a clade with close affinity to P. chinensis (Fig. 1 ). However, the species segregation within the taxa is not discrete in a multigene phylogeny. Comparing the ITS, LSU, SSU, and tub 2 regions between our strains and CBS 140326 (type strain), only 1 bp difference was found in the ITS, 3 bp difference in LSU and SSU, and no base pair differences in the tub 2. The morphology of our strains resembles the species description of P. chinensis provided by Li et al. (2017), except for the appearance of the conidiophores and chlamydospores and the lack of budding conidia. Although our strains have shorter conidia compared to P. chinensis CBS 140326 , the holotype isolated from skin lesions of a human chromoblastomycosis patient (2–5 × 1.6–3.9 μm vs 3–6 × 2.0–5.5 μm), the detail of other structures (i. e., collarette, conidiophore, conidiogenous cells and chlamydospores) was not mentioned. Hence, an updated morphology for the species P. chinensis is provided.

Figures

Figure 1. Phylogram generated from maximum likelihood analysis of members in Herpotrichiellaceae based on a combined ITS, LSU, SSU, and tub 2 sequence dataset. Bootstrap values ≥ 50 % MLBS and Bayesian posterior probabilities (PP) ≥ 0.90 are shown above nodes and defined as ML / PP. The tree is rooted to Cyphellophora laciniata (CBS 190.61) and C. suttonii (CBS 449.91). The fungal strains obtained in this study are blue. Ex-type strains are in bold. The scale bar represents the expected number of nucleotide substitutions per site.

Figure 3. Phialophora chinensis (SDBR-CMU 506, new host record). A – F. Colonies on PDA, MEA, OA, PCA, CMD and CMA, respectively, after 30 d at 25 ° C; G. Conidiophores sporulating on CMA; H. Conidiophores sporulating on PCA; I – M. Hyphal anastomosis; N – P. Hyphal coil; Q – AA. Phialides at different stages of development; AB – AD. Conidia; AE – AK. Chlamydospores (intercalary and chains formation). Scale bars: 100 µm (G, H); 10 µm (I – AA); 5 µm (AB – AD); 20 µm (AE – AK).