Distoseptispora euseptata W.L. Li, H.Y. Su & Jian K. Liu, Phytotaxa 520 (1): 80 (2021)

Shen, Hong-Wei, Bao, Dan-Feng, Boonmee, Saranyaphat, Lu, Yong-Zhong, Su, Xi-Jun, Li, Yun-Xia & Luo, Zong-Long, 2024, Diversity of Distoseptispora (Distoseptisporaceae) taxa on submerged decaying wood from the Red River in Yunnan, China, MycoKeys 102, pp. 1-28 : 1

Distoseptispora euseptata W.L. Li, H.Y. Su & Jian K. Liu, Phytotaxa 520 (1): 80 (2021)

Fig. 3

Description.

Saprobic on submerged decaying wood in a freshwater stream. Anamorph: Colonies on wood effuse, brown, solitary or in small group. Mycelium mostly immersed, composed of septate, brown hyphae, smooth-walled. Conidiophores (32-)37-59(-73) × 3-4(-5) µm (x̄ = 48 × 4 µm, n = 25), macronematous, mononematous, solitary or in groups, erect, straight or slightly flexuous, branched or unbranched, cylindrical, 2-4(-5)-septate, brown, smooth-walled. Conidiogenous cells (11-)13-15(-16) × 5-6 µm (x̄ = 14 × 5 µm, n = 20), monoblastic, terminal, determinate, subcylindrical, brown, smooth-walled. Conidia (36-)52-68(-85) × (7-)8-9 µm (x̄ = 60 × 8 µm, n = 30), acrogenous, solitary, obclavate, sometimes rostrate, truncate at base, tapering towards the apex, straight or slightly curved, guttulate, brown to dark brown, 6-9(-11)-euseptate, constricted at the septa, thin and smooth-walled. Teleomorph: Undetermined.

Culture characteristics.

Conidia germinating on PDA within 12 hrs and germ tubes produced from apex of conidium. Colonies growing on PDA reaching 4-5 cm in 20 days at 26 °C in the dark, with dense, velvety, pale brown to dark brown mycelium from above, dark brown from below.

Material examined.

China, Yunnan Province, Yuxi City, Xinping Yi and Dai Autonomous County, Yuanjiang River , 24°02′16"N, 101°34′05"E, on submerged decaying branches in a freshwater stream, 22 February 2022, S. Luan & W.P Wang YJ 14-49-1 (HKAS 125822, living culture KUNCC 22-12477) .

Notes.

Polygenetic analysis revealed that our new strain, KUNCC 22-12477, clustered with two strains of Distoseptispora euseptata (MFUCC 20-0154 and MFLU 20-0568) with 100% ML/1.00 PP support (Fig. 1 ). A comparison of the ITS and LSU sequence between strain KUNCC 22-12477 and MFLUCC 20-0153 (from holotype) revealed 0.74% (4/537 bp, including 1 gap), 0.16% (2/1254 bp, including 2 gaps), respectively. And a comparison of the ITS, LSU and rpb 2 sequence between strain KUNCC 22-12477 and DLUCC S2024 (from paratype) revealed 0.74% (4/537 bp, including 1 gap), 0% (0/1274 bp), and 0.23% (2/878 bp), respectively. New collection, KUNCC 22-12477, is morphologically similar to the type species in having obclavate, guttulate, euseptate conidia ( Li et al. 2021). Although the conidia size and color of D. euseptata KUNCC 22-12477 are slightly different from the type species, and conidia size is also an important basis for distinguishing Distoseptispora species, some previous studies in this genus found significant differences in conidial size between different collections of the same species ( Yang et al. 2018; Shen et al. 2021; Ma et al. 2022). Based on the currently limited morphological and molecular sequence data, we treat the new collection, KUNCC 22-12477, as D. euseptata , which was first discovered in the Red River Basin in Yunnan, China.

Figures

Figure 1. Maximum likelihood (ML) tree is based on combined LSU, ITS, tef 1 - α and rpb 2 sequence data. Bootstrap support values with a ML greater than 65 % and Bayesian posterior probabilities (PP) greater than 0.95 are given above the nodes, shown as " ML / PP ". The tree is rooted to Aquapteridospora fusiformis (MFLUCC 18 - 1606) and A. lignicola (MFLUCC 15 - 0377). New species are indicated in blue and type strains are in bold.

Figure 3. Distoseptispora euseptata (HKAS 125822) a colony on woody substrates b-e conidiophores f, g conidiogenous cells h-m conidia n germinated conidium o culture on PDA. Scale bars: 20 μm (b-e, h-n); 10 μm (f, g).