Nigropunctata puerzhenensis C. T. Lu, K. Habib & Q. R. Li, 2025

Nigropunctata puerzhenensis C. T. Lu, K. Habib & Q. R. Li sp. nov.

Fig. 3 View Figure 3

Etymology.

The specific epithet “ puerzhenensis ” refers to Puer Village, where the holotype specimen was collected.

Type.

China • Yunnan Province, Zhaotong City, Puer Town ( 28°17'35.32"N, 103°59'28.57"E), altitude: 1154 m, on dead culms of bamboo, 21 August 2024, Changtao Lu, 2024 PEZ 5 ( GMB 4904 , holotype, no culture was obtained) GoogleMaps ; ibid KUN-HKAS 146984 , isotype GoogleMaps .

Description.

Saprobic on dead culms of bamboo. Sexual morph: Ascomata 870–1230 µm wide, 760–910 µm high, immersed, solitary, scattered, appearing as small black dots, with minute clypeus, in cross-section globose to subglobose with a flattened base. Ostioles centric, slightly papillate, black, flush with the surface of the host. Peridium 15–36.5 µm thick, comprised of two layers; outer layer composed of thick-walled, dense, dark brown, cells of textura angularis; inner layer hyaline cells of textura angularis. Paraphyses 2–6 µm (x ̄ = 4 µm, n = 30) wide, longer than the asci, numerous, filamentous, guttulate. Asci 159–233 × 10–26 µm (x ̄ = 190 × 17.5 µm, n = 30) 8 - spored, unitunicate, cylindrical, short-pedicellate, apically rounded, with a J +, discoid apical apparatus, 0.5–1.7 µm high, 2.5–4.5 µm wide (x ̄ = 1.0 × 3.5 µm, n = 30). Ascospores 13–20 × 5.6–7.5 µm (x ̄ = 16 × 6.5 µm, n = 30), uniseriate, unicellular, brown to dark brown, oblong to broadly ellipsoidal, with a germ slit, straight, along the entire spore length, surrounded by thick 2–6 µm (x ̄ = 3 µm, n = 30) mucilaginous sheath. Asexual morph: Undetermined.

Paratype.

China • Yunnan Province, Zhaotong City, Puer Town ( 28°17'56.77"N, 103°59'47.34"E), altitude: 1168 m, on dead culms of bamboo, 21 August 2024, Changtao Lu, 2024 PEZ 11 ( GMB 4953 , paratype) GoogleMaps .

Notes.

Morphologically and phylogenetically, Nigropunctata puerzhenensis is closely related to N. nigrocircularis . Both species share an amyloid ascus apical apparatus and ascospores surrounded by a thick mucilaginous sheath. However, N. nigrocircularis differs from N. puerzhenensis by having smaller ascomata (450–535 × 455–560 μm vs. 870–1230 × 760–910 μm), a thinner peridium (11–20 μm vs. 15–36.5 μm thick) and shorter asci (125–170 μm vs. 159–233 μm in length) ( Samarakoon et al. 2022). Comparative analysis of nucleotide base pairs showed that N. puerzhenensis differs from N. nigrocircularis ( MFLU 19-2130 ) by 3.2 % (11 / 342) in the ITS locus, 1.4 % (13 / 928) in the LSU locus, 1.4 % (12 / 889) in the tef- 1 a gene and 1.0 % (4 / 422) in the tub 2 gene. Nigropunctata puerzhenensis can be distinguished from all currently known species in the genus ( Habib et al. 2025) by its larger asci. Comparison with other species of the genus is presented in Table 2 View Table 2 .