Research Article |
Corresponding author: Zong-Long Luo ( luozonglongfungi@163.com ) Academic editor: Jennifer Luangsa-ard
© 2021 Hong-Wei Shen, Dan-Feng Bao, Kevin D. Hyde, Hong-Yan Su, Darbhe J. Bhat, Zong-Long Luo.
This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY 4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Citation:
Shen H-W, Bao D-F, Hyde KD, Su H-Y, Bhat DJ, Luo Z-L (2021) Two novel species and two new records of Distoseptispora from freshwater habitats in China and Thailand. MycoKeys 84: 79-101. https://doi.org/10.3897/mycokeys.84.71905
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During investigations into freshwater fungi from the Great Mekong Subregion, four Distoseptispora taxa were collected from China and Thailand. Based on morphological characteristics, and phylogenetic analyses of combined LSU, ITS, SSU, TEF1-α, and RPB2 sequence data, two new species Distoseptispora bangkokensis and D. lancangjiangensis are introduced, and two known species D. clematidis and D. thysanolaenae were first reported in freshwater habitat. Illustrations and descriptions of these taxa are provided, along with comparisons with extant taxa in the genus.
2 new taxa, Distoseptisporales, freshwater fungi, morphology, phylogeny, taxonomy
Distoseptisporaceae was introduced by
Distoseptispora as a single genus in Distoseptisporaceae was introduced by
During our ongoing study of freshwater fungi along the north-south gradient in the Asian/Australian region (
Specimens of submerged decaying wood were collected from Dulongjiang, Nanpanjiang, Lancangjiang and Chao Phraya River in China and Thailand respectively. Multiple samples will be collected at each collection site at different times, allowing more strains to be obtained for each species. Methods of morphological observation and isolation follow
DNA extraction, PCR amplification, sequencing and phylogenetic analysis follow Dissayanake et al. (2020) with the following modifications. Fungal mycelia (200–500 mg) were scraped from grown on PDA/MEA plates using sterile scalpel, transferred to microcentrifuge tube with sterilized needles, and then grind with liquid nitrogen or quartz sand to break the cells. DNA was extracted using the TreliefTM Plant Genomic DNA Kit (TSP101) according to the manufacturer’s instructions.
Five gene regions, LSU, ITS, SSU, TEF1-α, and RPB2 were amplified using LR0R/LR5, ITS5/ITS4, NS1/NS4, 983F/EF1-2218R, and RPB2-5F/RPB2-7cR (
Preliminary identification of genes obtained from fresh strains by GenBank database. The LSU, ITS, SSU, TEF1-α, and RPB2 used for phylogenetic analysis are selected based on the preliminary identification results and the related publications (
Maximum likelihood (ML) analysis was carried out using the RAxML-HPC2 on XSEDE (8.2.12) (
Bayesian analyses were performed in MrBayes 3.2.6 (
Phylogenetic trees were visualized using FigTree v1.4.0 (
Strains used for phylogenetic analysis and their corresponding GenBank numbers. The type strain are in bold font.
Species | Source | GenBank accession number | Reference | ||||
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LSU | ITS | TEF1-α | RPB2 | SSU | |||
Aquapteridospora fusiformis |
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MK849798 | MK828652 | MN194056 | – | – |
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A. lignicola |
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KU221018 | – | – | – | – |
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Distoseptispora adscendens | HKUCC 10820 | DQ408561 | – | – | DQ435092 | – |
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D. appendiculata |
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MN163023 | MN163009 | MN174866 | – | – |
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D. aquatica |
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KU376268 | MF077552 | – | – | – |
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D. bambusae |
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MT232718 | MT232713 | MT232880 | MT232881 | MT232716 |
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D. bambusae |
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MT232717 | MT232712 | – | MT232882 | – |
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D. bangkokensis |
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MZ518206 | MZ518205 | – | – | MZ518208 | This study |
D. cangshanensis |
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MG979761 | MG979754 | MG988419 | – | – |
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D. caricis | CBS 146041 | MN567632 | MN562124 | – | MN556805 | – | Crous et al. (2019) |
D. clematidis |
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MT214617 | MT310661 | – | MT394721 | MT226728 |
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D. clematidis | KUN-HKAS 112708 | MW879523 | MW723056 | MW729784 | – | MW774580 | This study |
D. dehongensis | KUMCC 18-0090 | MK079662 | MK085061 | MK087659 | – | – |
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D. euseptata | MFUCC 20-0154 | MW081544 | MW081539 | – | MW151860 | – |
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D. euseptata | DLUCC S2024 | MW081545 | MW081540 | MW084994 | MW084996 | – |
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D. fasciculata | KUMCC 19-0081 | MW287775 | MW286501 | MW396656 | – | – |
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D. fluminicola |
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KU376270 | MF077553 | – | – | – |
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D. guttulata |
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MF077554 | MF077543 | MF135651 | – | MF077532 |
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D. hydei |
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MT742830 | MT734661 | – | MT767128 | – |
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D. lancangjiangensis | KUN-HKAS 112712 | MW879522 | MW723055 | – | MW882260 | – | This study |
D. leonensis | HKUCC 10822 | DQ408566 | – | – | DQ435089 | – |
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D. lignicola |
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MK849797 | MK828651 | – | – | MK828318 |
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D. longispora | HFJAU 0705 | MH555357 | MH555359 | – | – | MH555431 |
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D. martinii |
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KX033566 | KU999975 | – | – | KX033537 |
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D. multiseptata |
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MF077555 | MF077544 | MF135652 | MF135644 | MF077533 |
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D. multiseptata |
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KX710140 | KX710145 | MF135659 | – | NG_065693 | Hyde et al. (2016) |
D. neorostrata |
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MN163017 | MN163008 | – | – | – |
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D. obclavata |
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MN163010 | MN163012 | – | – | – |
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D. obpyriformis |
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MG979764 | – | MG988422 | MG988415 | – |
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D. obpyriformis | DLUCC 0867 | MG979765 | MG979757 | MG988423 | MG988416 | – |
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D. palmarum |
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MK079663 | MK085062 | MK087660 | MK087670 | MK079661 |
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D. phangngaensis |
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MF077556 | MF077545 | MF135653 | – | MF077534 |
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D. rayongensis |
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MH457137 | MH457172 | MH463253 | MH463255 | MH457169 | Hyde et al. (2012) |
D. rostrata |
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MG979766 | MG979758 | MG988424 | MG988417 | – |
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D. saprophytica |
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MW287780 | MW286506 | MW396651 | MW504069 | – |
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D. songkhlaensis |
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MW287755 | MW286482 | MW396642 | – | – |
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D. suoluoensis |
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MF077557 | MF077546 | MF135654 | – | MF077535 |
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D. suoluoensis |
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MF077558 | MF077547 | – | – | MF077536 |
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D. tectonae |
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KX751713 | KX751711 | KX751710 | KX751708 | – | Hyde et al. (2016) |
D. tectonae*1 |
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MG979768 | MG979760 | MG988426 | MG988418 | – |
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D. tectonigena |
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KX751714 | KX751712 | – | KX751709 | – | Hyde et al. (2016) |
D. thailandica |
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MH260292 | MH275060 | MH412767 | – | MH260334 |
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D. thysanolaenae | KUN-HKAS 102247 | MK064091 | MK045851 | MK086031 | – | – |
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D. thysanolaenae | KUN-HKAS 112710 | MW879524 | MW723057 | MW729783 | – | – | This study |
D. xishuangbannaensis | KUMCC 17-0290 | MH260293 | MH275061 | MH412768 | MH412754 | MH260335 |
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D. yunnanensis |
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MW081546 | MW081541 | MW084995 | MW151861 | – |
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Myrmecridium aquaticum |
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MK849804 | – | – | – | MK828323 |
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M. aquaticum | S-1158 | MK849803 | MK828656 | MN194061 | MN124540 | MK828322 |
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M. banksiae | CBS 132536 | JX069855 | JX069871 | – | – | – |
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Pseudostanjehughesia aquitropica |
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MF077559 | MF077548 | MF135655 | – | MF077537 |
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P. lignicola |
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MK849787 | MK828643 | MN194047 | MN124534 | – |
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Sporidesmium dulongense |
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MH795817 | MH795812 | MH801191 | MH801190 | – |
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S. lageniforme | DLUCC 0880 | MK849782 | MK828640 | MN194044 | MN124533 | – |
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S. pyriformatum |
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KX710141 | KX710146 | MF135662 | MF135649 | – | Hyde et al. (2016) |
S. thailandense |
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MF077561 | MF077550 | MF135657 | – | – |
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S. thailandense |
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MF374370 | MF374361 | MF370957 | MF370955 | – |
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The dataset composed of LSU (1–744 bp), ITS (745–1310 bp), TEF1-α (1311–2161 bp), RPB2 (2162–3178 bp), and SSU (3179–4199 bp) gene, comprising a total of 4199 characters (including gaps), including 56 taxa with Pseudostanjehughesia aquitropica (
Maximum likelihood (ML) tree is based on combined of LSU, ITS, SSU, TEF1-α, and RPB2 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 (
The phylogenetic tree shows that the new species Distoseptispora bangkokensis (
Comparison of morphological characteristic, habitats and hosts’ information of species added to Distoseptispora after
Species | Conidiophore (μm) | Conidia (μm) | Conidia septation | Conidia characteristic | Habitat | Host | Reference |
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Distoseptispora bangkokensis | 37–55 × 3–4 | 400–568 × 13–16 | Multi-distoseptate | Elongate, obclavate, rostrate, dark olivaceous to dark brown | Freshwater | Unidentified submerged wood | This study |
D. lancangjiangensis | 30–41 × 5–6 | 83–220 × 12–14 | 16–41-distoseptate | Obclavate, cylindrical, elongated, straight or curved, brown to greenish-brown | Freshwater | Unidentified submerged wood | This study |
D. euseptata | 19–28 × 4–5 | 37–54 × 8–9 | 4–7-euseptate | Obpyriform to obclavate, straight or curved, olivaceous | Freshwater | Unidentified submerged wood |
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D. fasciculata | 12–16 × 5–6 | 46–200 × 10–16.5 | 10–40-distoseptate | Subcylindrical to obclavate, mostly curved, olivaceous when young, dark brown when mature | Freshwater | Unidentified submerged wood |
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D. longispora | 17–37 × 6–10 | 189–297 × 16–23 | 31–56-distoseptate | Obclavate, elongated, straight or slightly curved, to yellowish brown | Freshwater | Unidentified submerged wood |
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D. saprophytica | 50–140 × 3.2–4.2 | 14.5–30 × 4.5–7.5 | 2–6-distoseptate | Subcylindrical to obclavate, straight or curved, olivaceous to brown | Freshwater | Unidentified submerged wood |
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D. songkhlaensis | 70–90 × 4–5.5 | 44–125 × 9–14.5 | 9–16-distoseptate | Obclavate, straight or curved, olivaceous to brown | Freshwater | Unidentified submerged wood |
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D. yunnanensis | 131–175 × 6–7 | 58–108 × 8–10 | 6–10-euseptate | Obclavate, rostrate, straight or slightly curved, mid olivaceous to brown | Freshwater | Unidentified submerged wood |
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Referring to the collecting location, Bangkok, Thailand.
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.
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 (
Distoseptispora bangkokensis is comparable to D. cangshanensis and D. multiseptata in having elongate, obclavate, or rostrate conidia (
Referring to the collecting location, Lancangjiang River in China.
KUN-HKAS 112712
Saprobic on submerged wood in freshwater River. Sexual morph: Undetermined. Asexual morph: Colonies effuse, hairy, glistening, brown to dark. Mycelium partly immersed in the substratum, composed of hyaline to pale brown, septate, branched hyphae. Conidiophores 144–204 × 5–6 μm (x¯ = 175 × 6 μm, n = 20) macronematous, mononematous, solitary, inflate at the base, cylindrical, straight or slightly flexuous, 6–11-septate, dark brown, hyaline and rounded at apex. Conidiogenous cells 12–24 × 4–5 μm (x¯ = 18 × 5 μm, n = 20) integrated, terminal, monoblastic, cylindrical, brown. Conidia 64–84 × 9–10 μm (x¯ = 74 × 10 μm, n = 20), acrogenous, solitary, narrowly obclavate or obspathulate, tracted at base, tapering towards apex, 3–10-euseptate, brown to dark brown, thin-walled, becoming paler or hyaline towards apex, guttulate, with a darkened scar at base, smooth-walled.
Distoseptispora lancangjiangensis (KUN-HKAS 112712, holotype) A colonies on the substratum B conidiophore and conidium C-E conidiophores F, G conidiogenous cells H conidiogenous cell with conidium I-Q conidia R germinating conidium S, T culture on PDA. Scale bars: 50 μm (B-E); 20 μm (F-R).
Conidia cultivated on PDA within 12h and germ tubes produced at the apex. Colonies on PDA, reaching 4.5 cm in 1 month at room temperature (25 °C). Mycelium loose, flocculent, smooth edges, convex middle, pale brown to dark brown on the surface of PDA. Smooth, black on the reverse.
China, Yunnan Province, Dali City, Lancangjiang River, 22°36'36"N; 100°37'59"E, on submerged decaying wood, 20 July 2017, Qishan Zhou and Qingxiong Ruan S–1864 (KUN-HKAS 112712, holotype;
Phylogenetic analysis showed that Distoseptispora lancangjiangensis clustered as a sister taxon to D. suoluoensis with 97%ML/0.98PP support. Distoseptispora lancangjiangensis is similar to D. suoluoensis in having long conidiophores, monoblastic conidiogenous cells, and obclavate to rostrate, euseptate conidia. However, D. suoluoensis has yellowish-brown or dark olivaceous, verrucose conidia, while in D. lancangjiangensis conidia are brown to dark brown and smooth-walled. Moreover, D. lancangjiangensis has smaller conidia than those of D. suoluoensis (64–84 × 9–10 μm vs. 80–125 × 8–13 μm) (
Saprobic on submerged wood in freshwater River. Sexual morph: Undetermined. Asexual morph: Colonies on the substratum superficial, effuse, scattered, hairy, dark brown. Mycelium partly immersed in substrate, composed of branched, smooth, septate, brown to dark brown hyphae. Conidiophores 30–41 × 5–6 μm (x¯ = 36 × 6 μm, n = 15), macronematous, mononematous, single or in a small group, straight or slightly flexuous, unbranched, septate, erect, 2–4-septate, cylindrical, smooth, dark brown to brown. Conidiogenous cells 7–9 × 5–6 μm (x¯ = 8 × 5 μm, n = 15), monoblastic, integrated, determinate, terminal, cylindrical, pale brown to brown. Conidia 83–220 × 12–14 μm (x¯ = 151 × 13 μm, n = 20), acrogenous, solitary, obclavate, cylindrical, elongated, straight or curved, truncate at base, rounded at apex, 16–41-distoseptate, slightly constricted at some septa, smooth, brown to greenish-brown, thick-walled.
Conidia cultivated on PDA within 12h and germ tubes produced at the ends. Colonies on PDA, attaining 4 cm after 1 month at room temperature (25 °C), gray at first, later becoming dark gray, loose, flocculent, smooth edge, dark brown on the reverse.
China, Yunnan Province, Kunming City, Yiliang County, Nanpanjiang River, 24°38'28"N; 103°09'38"E, on submerged decaying wood, 12 June 2018; Hongwei Shen and Xiu He, S–1797 (KUN-HKAS 112708), living culture (DLUCC 1797).
Our new isolate clustered with the ex-type strain of Distoseptispora clematidis (
Saprobic on submerged wood in freshwater River. Sexual morph: Undetermined. Asexual morph: Colonies on the substratum superficial, effuse, scattered, hairy, dark brown. Mycelium partly immersed, composed of branched, septate, smooth, brown to dark brown hyphae. Conidiophores 41–59 × 4–5 μm (x¯ = 50 × 5 μm, n = 20) macronematous, mononematous, unbranched, single, erect, straight or slightly curved, smooth, 3–6-septate, pale brown to brown. Conidiogenous cells monoblastic, integrated, determinate, terminal, dark brown, cylindrical. Conidia 46–87 × 9–12 μm (x¯ = 67 × 10 μm, n = 25) acrogenous, solitary, dry, smooth, obclavate, elongated, straight or slightly curved, truncate at base, tapering towards apex, 6–19-septate, dark grayish-brown to light yellow-green, thick-walled.
Conidia cultivated on PDA within 12 h and germ tubes produced at the apex. Colonies on PDA, reaching 6 cm after 6 weeks at room temperature (25 ℃). Mycelium loose, flocculent, neat edges, convex in middle, pale brown to dark brown. Black, smooth on the back.
China, Yunnan Province, Lushui City, Nujiang River, 26°23'12"N; 98°53'94"E, on submerged decaying wood, 3 May 2016, Zonglong Luo and Songming Tang, S-876 (KUN-HKAS 112710), living culture (DLUCC 876 = KUNCC 21-10710)
Our new collection is identical to Distoseptispora thysanolaenae in characters of the conidiophores, conidiogenous cell, and conidia (
Distoseptispora has been reported from both freshwater and terrestrial habitats. Of these, species have been collected from freshwater environments (
Species of Distoseptispora are highly diverse in morphology, especially the conidial shape. Conidia of most species are obclavate to cylindrical or rostrate (e.g. D. aquatica, D. tectonae, and D. suoluoensis), but a few are ellipsoid to subglobose (e.g. D. martinii), lanceolate (e.g. D. guttulata and D. multiseptata), and some species have conidia with a sheath at the apex (e.g. D. appendiculata) (
Based on the key morphological characteristics, viz. conidiophores, conidiogenous cells, and conidia,
Based on phylogenetic analysis,
We would like to thank the National Natural Science Foundation of China (Project ID: 32060005 and 31970021), and Fungal Diversity Conservation and Utilization Innovation Team of Dali University (ZKLX2019213) for financial support. Kevin D Hyde thanks the Thailand Research Fund for the grant (RDG6130001MS), Impact of climate change on fungal diversity and biogeography in the Greater Mekong Subregion. Hongwei Shen thanks Saranyaphat Boonmee for her help in sample collection and herbarium deposit. Qishan Zhou, Qingxiong Ruan, Songming Tang, and Xiu He are thanked for their help on sample collection. We are grateful to Yanmei Zhang, Longli Li, and Wenli Li for their help on DNA extraction and PCR amplification.