Phaeoisaria clematidis (Fuckel) S. Hughes, Can. J. Bot.

Xu, Ke, Xu, Rong-Ju, Li, Jia-Ning, Zhao, Qi & Zhu, Ying-An, 2024, A novel species of Phaeoisaria (Pleurotheciaceae, Sordariomycetes) from the Tibetan Plateau, China, Phytotaxa 642 (1), pp. 61-72 : 65-66

Phaeoisaria clematidis (Fuckel) S. Hughes, Can. J. Bot. 36: 794 (1958) FIGURE 2

Index Fungorum number: 302703, Facesoffungi number: 03412

Saprobic on decaying submerged wood in a freshwater stream. Asexual morph: Conidiomata scattered, indeterminate, erect, superficial, dark brown, composed of compact appressed conidiophores. Synnemata 164–600 × 6–28 μm (x = 290 × 13 μm, n = 20), macronematous, branched, synnematous, septate, brown to dark brown, smooth. Conidiogenous cells 7–43 × 2–4 μm (x = 25 × 3 μm, n = 30), polyblastic, hyaline to pale brown, integrated or discrete, sympodial, terminal, denticulate. Conidia 4–6 × 2–3 μm (x = 5 × 2 μm, n = 35), ellipsoidal to obovoid, hyaline, smooth-walled, aseptate. Sexual morph: Undetermined.

Culture characteristics: Conidia germinated on PDA within 48 hours, and germ tubes were produced from both ends. Colony reached 50 mm at room temperature for four weeks, appressed, circular, flat, cream, and raised in the center with mycelium.

Material examined: CHINA, Xizang, Qamdo City, Basu County, Ranwu Town, Ranwu Lake, saprobic on decaying submerged wood in a freshwater lake, 14 July 2022, R.J. Xu, MD-628 ( HKAS 128985), living culture, KUNCC 10455. Motuo County, saprobic on decaying wood submerged in a freshwater stream, 11 July 2022, R.J. Xu, XK-28 ( HKAS 128988), living culture, KUNCC 10458. Shigatse City, Yadong County, saprobic on decaying submerged wood in a freshwater stream, 1 July 2022, R.J. Xu, LTS-16 ( HKAS 128989), living culture, KUNCC 10459.

Notes: Phaeoisaria clematidis , initially described by Hughes (1958), is known to occur on various substrates and is widely distributed ( Ellis 1971, Crous et al. 2015, Luo et al. 2018). In China, P. clematidis was reported by Luo et al. (2018) from submerged decaying wood in Yunnan Province. In our study, five strains were isolated from submerged decaying woods in freshwater habitats from the Tibetan Plateau, China. Morphologically, our collections fit well with those of P. clematidis , in having macronematous, branched synnemata, polyblastic, hyaline, denticulate conidiogenous cells, and ellipsoidal to obovoid, hyaline conidia. Simultaneously, phylogenetic analyses showed our strains clustered with P. clematidis ( MFLUCC 17-1341) with strong statistical support ( FIGURE 1 ). Therefore, we identified the new isolates as P. clematidis based on morphological and phylogenetic data, and reported it for the first time from the Tibetan Plateau.

Figures

FIGURE 1. The phylogenetic tree obtained from RAxML analysis with combined ITS, LSU, and SSU sequence data. Bootstrap support values for ML equal to or greater than 75% and PP for BI equal to or greater than 0.95 were indicated at the nodes. Pleurotheciella rivularia (CBS 125237) and Pl. rivularia (CBS 125238) were selected as the outgroup taxa. The new isolates are in blue, and the type species are in bold.

FIGURE 2. Phaeoisaria clematidis (HKAS 128987). a Colony on a natural substrate. b, c Conidiophore and Conidiogenous cell. d–i Conidiogenous cell. j–o Conidia. p Germinating conidium. q Colony on PDA. Scale bars: b–c = 50 μm, d–f = 20 μm, g–i = 10 μm, j–p = 5 μm.