Distoseptispora bangkokensis H.W. Shen, D.F. Bao, K.D. Hyde & Z.L. Luo, 2021

Shen, Hong-Wei, Bao, Dan-Feng, Hyde, Kevin D., Su, Hong-Yan, Bhat, Darbhe J. & Luo, Zong-Long, 2021, Two novel species and two new records of Distoseptispora from freshwater habitats in China and Thailand, MycoKeys 84, pp. 79-101 : 79

Distoseptispora bangkokensis H.W. Shen, D.F. Bao, K.D. Hyde & Z.L. Luo sp. nov.

Figure 2

Etymology.

Referring to the collecting location, Bangkok, Thailand.

Holotype.

MFLU 21-0110

Description.

Saprobic on submerged wood in freshwater stream. Sexual morph: Undetermined. Asexual morph: Colonies effuse, glistening, hairy, brown to dark brown. Mycelium partly superficial in the substratum, composed of hyaline to pale brown, septate, branched hyphae. Conidiophores 37-55 × 3-4 μm (x¯ = 46 × 3 μm, n = 15) macronematous, mononematous, solitary or in a small group of 2-4, cylindrical, straight or slightly flexuous, 3-8-septate, dark brown, paler at the apical part, rounded at the apex. Conidiogenous cells 6-8 × 3-4 μm (x¯ = 7 × 3 μm, n = 15), integrated, terminal, monoblastic, cylindrical, brown. Conidia 400-568 × 13-16 μm (x¯ = 484 × 15 μm, n = 20), 6-7 μm at the narrowest apical region, acrogenous, solitary, elongate, obclavate, rostrate, multi-distoseptate, tapering towards the apex, truncate at the base, rounded at apex, dark olivaceous to dark brown, straight or slightly curved, guttulate, thick-walled, smooth, conidia percurrent proliferation which forms another conidium at the apex.

Culture characteristics. Conidia cultivated on PDA within 12h and germ tubes produced at the ends. Colonies on PDA, reaching 6 cm in 1 month at room temperature (25 °C). Mycelium loose, flocculent, smooth edge, brown to dark brown, dark brown on the reverse.

Material examined.

Thailand, Bangkok Province, Khwaeng Phra Khanong Nuea , 13°42'41"N; 100°36'03"E, on submerged decaying wood, 1 October 2017, Zonglong Luo, S-3083 (MFLU 21-0110, holotype), ex-type living culture (MFLUCC 18-0262) .

Notes.

Distoseptispora bangkokensis is comparable to D. cangshanensis and D. multiseptata in having elongate, obclavate, or rostrate conidia ( Su et al. 2016; Hyde et al. 2016a; Yang et al. 2018). However, D. bangkokensis has shorter and narrower conidiophores than those of D. cangshanensis (37-55 × 3-4 μm vs. 44-68 × 4-8 μm), but has longer conidia (400-568 μm vs. 58-166 μm); D. multiseptata (MFLU 17-0856) is similar to D. bangkokensis in conidial morphology, with conidia mostly 300-600 μm long (up to 700 μm) and significantly longer than those of the holotype (up to 380 μm long). However, Yang et al. (2018) did not give a detailed description of D. multiseptata (MFLU 17-0856). Phylogenetic analyses showed that D. bangkokensis clustered with D. bambusae , D. dehongensis , D. euseptata , D. lancangjiangensis , D. suoluoensis , D. thysanolaenae , and D. yunnanensis with low bootstrap support (26%ML/0.53PP, Figure 1 ). Distoseptispora bangkokensis is distoseptate conidia, and it is easily distinguished from D. bambusae , D. euseptata , D. lancangjiangensis , D. suoluoensis , and D. yunnanensis , which are euseptate. Distoseptispora bangkokensis is resemble to D. dehongensis and D. thysanolaenae in having obclavate, distoseptae conidia, but are distinguished by conidia characteristics, D. bangkokensis has elongate, obclavate, rostrate, multi-distoseptat, and longer conidia than D. dehongensis (400-568 × 13-16 μm vs. 17-30 × 7.5-10 μm) and D. thysanolaenae (400-568 × 13-16 μm vs. 30-70 × 5-8 μm), respectively.

Figures

Figure 1. Maximum likelihood (ML) tree is based on combined of LSU, ITS, SSU, TEF 1 - α, and RPB 2 sequence data. Bootstrap support values with an ML greater than 70 % and Bayesian posterior probabilities (PP) greater than 0.97 given above the nodes, shown as " ML / PP ". The tree is rooted with Pseudostanjehughesia aquitropica (MFLUCC 16 - 0569) and P. lignicola (MFLUCC 15 - 0352). New species are indicated in red and type strains are in bold.

Figure 2. Distoseptispora bangkokensis (MFLU 21 - 0110, holotype) A colonies on the substratum B conidiophores C conidiophores with conidia D conidiogenous cell E-G conidia H germinating conidium Scale bars: 20 μm (B, C, H); 10 μm (D); 50 μm (E-G).