Sporidesmium ailaoshanense Q. F. Zhang & Q. R. Li, 2025

Sporidesmium ailaoshanense Q. F. Zhang & Q. R. Li sp. nov.

Fig. 3 View Figure 3

Etymology.

The specific epithet refers to the location where the holotype specimen was collected, Ailaoshan National Nature Reserve.

Type.

China • Yunnan Province, Ailaoshan National Nature Reserve ( 24°5'7.01"N, 101°31'30.44"E), altitude: 1169 m, on dry rotten wood, 15 September 2024, Qinfang Zhang, 2024 ALS 74 ( GMB 5103 , holotype; GMBC 5103 , ex-type); KUN-HKAS 146988 , isotype GoogleMaps .

Description.

Saprobic on decaying twigs of an unknown wood. Sexual morph: undetermined. Asexual morph: Colonies on the substratum superficial, effuse, scattered, hairy, black. Mycelium immersed, composed of branched, septate, smooth, pale brown to brown hyphae. Conidiophores 110–184 × 4–7 µm (av. = 135 × 6.2 µm, n = 30), macronematous, mononematous, unbranched, erect, straight or slightly flexuous, smooth, thick-walled, septate, not clear, cylindrical, dark brown, paler towards apex, smooth, and thick-walled. Conidiogenous cells 10–16 × 4–9 µm (av. = 13.2 × 7.1 µm, n = 30), monoblastic, integrated, determinate or sometimes percurrently proliferating, terminal, pale brown, cylindrical. Conidia 42–58 × 13–22 µm (av. = 49.0 × 17.4 µm, n = 30), acrogenous, solitary, dry, pyriform or lageniform, truncate at the base, smooth, dark brown, paler towards the apex, 4–5 µm wide and truncate at the base, thick-walled, 3–5 µm wide at the apex, 6–8 - septate, slightly constricted at the septa, Conidial secession schizolytic.

Culture characteristics.

Conidia germinate on WA within 12 hours. At 25 ° C, colonies growing on PDA reach a diameter of 20–30 mm after three weeks. The colonies are convex, with a smooth surface, mycelium present, dry, flat, and wrinkle-free. From above, the center appears white, with a grayish-white edge, while from below, the colony center is dark brown to black. No pigmentation is produced in the culture medium.

Additional material examined.

China • Yunnan Province, Ailaoshan National Nature Reserve ( 24°5'4.82"N, 101°31'32.89"E), altitude: 1131 m, on a dry wood branch, 15 September 2024, Qinfang Zhang, 2024 ALS 131 ( GMB 5107 , GMBC 5107 ) GoogleMaps .

Notes.

Phylogenetically, Sporidesmium ailaoshanense is closely related to S. dulongense (MFLUCC- 17-0116) (Fig. 1 View Figure 1 ). Morphologically, the two species share similar conidial shape and length. However, S. ailaoshanense can be distinguished by its longer conidiophores (110–184 μm vs. 88–124 μm) and wider conidia (13–22 μm vs. 13–15 μm) ( Hyde et al. 2020). Moreover, S. dulongense has conidia with a long hyaline apex, which is very short in S. ailaoshanense . Base pair comparisons also support their separation; the ITS, LSU, and rpb 2 sequences of S. ailaoshanense ( GMB 5103 ) and S. dulongense (MFLUCC- 17-0116) show 97.0 % sequence identity in ITS, 99.6 % in LSU, and 97.64 % in rpb 2.

Sporidesmium submersum also shares a similar conidial shape and length with S. ailaoshanense , including a short hyaline apex. However, it differs in having much shorter conidiophores (59–72 μm vs. 110–184 μm) and thinner conidia (14–16 μm vs. 13–22 μm) ( Su et al. 2016).