Xylaria nanningensis W. Y. Zeng & Q. R. Li, 2024

Zeng, Wenyu, Habib, Kamran, Zhou, Xin, Ren, Yulin, Shen, Xiangchun, Wang, Bei, Kang, Yingqian, Kang, Jichuan & Li, Qirui, 2024, Morphology and multigene phylogeny reveal four new Xylaria (Xylariales, Xylariaceae) species from karst region in China, MycoKeys 108, pp. 169-196 : 169-196

Xylaria nanningensis W. Y. Zeng & Q. R. Li sp. nov.

Fig. 3

Etymology.

The specific epithet refers to its collection location, Nanning City.

Type.

China. • Guangxi Province, Nanning City, Liangfengjiang National For-est Park , 22 ° 43 ' 28 ″ N, 108 ° 16 ' 59 ″ E, elev. 97 m, on fallen leaves of unknown plants, August 2023, Wenyu Zeng & Xin Zhou, LFJ 1 ( GMB 4702 Holotype; KUN - HKAS 134916 Isotype; GMBC 4702 ex-type) .

Description.

Saprobic on fallen leaves of unknown plants. Sexual morph: Stromata 1.1–2.8 cm in total length, solitary, upright, unbranched, with capitate fertile apex, head conical to subglobose 0.5–1.2 mm diam × 0.5–1.8 mm thick, consists of closely packed perithecia, surface black, rounded, on a long stipe, slightly swollen at base, rough. Externally black, interior white, texture soft. Stipes thin, glabrous, up to 2 cm long. Perithecia 85–395 μm diam., oval to spherical, embedded, closely arranged, interior white. Ostioles slightly papillate. Asci 114–156 × 6.8–13.6 μm (x ̄ = 135 × 10.2 μm, n = 30), 8 - spored, unitunicate, cylindrical, apically rounded, with an inverted hat shaped apical apparatus, blue staining in Melzer’s reagent, 5.2–5.7 × 4.9–5.4 μm (x ̄ = 5.5 × 5.2 μm, n = 30). Ascospores 15.0–24.1 × 4.4–7.4 μm (x ̄ = 19.0 × 5.5 μm, n = 30), uniseriate, unicellular, hyaline when immature, slight brown to dark brown at maturity, ellipsoid-inequilateral, with rounded ends, smooth, each end surround a round sheath, up to 5 × 5 μm, lacking germ slit; epispore smooth. Asexual morph: Undetermined.

Culture characteristics.

Colonies on OA reaching 3–4 cm diam. after 2 weeks at 25 ° C, white at first, with irregular margins, then extension spreading toward the edge of the Petri dish; the overall color is light white.

Additional material examined.

China. • Guangxi Province, Nanning City, Liangfengjiang National Forest Park , 22 ° 43 ' 28 ″ N, 108 ° 16 ' 59 ″ E, elev. 207 m, on fallen leaves of unknown plants, August 2023, Wenyu Zeng & Xin Zhou, LFJ 1-1 ( GMB 4706 ; GMBC 4706 ) .

Notes.

In the phylogram (Fig. 1 ), it is closely related to X. ficicola . The latter can be distinguished by the size of stromata stipe, asci and ascospores ( Pan et al. 2022). Xylaria nanningensis has less than 2 cm long stipe (vs. up to 6 cm long in X. ficicola ), asci measuring 114–156 × 6.8–13.6 μm (vs. 190–220 × 8–10 μm in X. ficicola ) and ascospores measuring 15.0–24.1 × 4.4–7.4 μm (vs. 16–22.7 × 6.5–8.5 μm in X. ficicola ). Moreover, the apical apparatus of the new species is slightly smaller (5.2–5.7 × 4.9–5.4 μm vs. 5–7.5 × 3–3.5 μm) ( Ma et al. 2011). Morphologically, X. nanningensis is similar to X. guazumae F. San Martín & J. D. Rogers ( San and Rogers 1989), but the latter grows on the fallen fruits of Guazuma ulmifolia Lam. ( Sterculiaceae ) and has relatively smaller ascospores (14–19 × 5.5–6 μm) and smaller rectangular apical ring (2.8–3.2 × 2–2.5 μm) ( San and Rogers 1989). Another morphologically close species is X. polysporicola Hai X. Ma & X. Y. Pan , but the latter can be distinguished by its stromata which has acute sterile apex up to 2 mm long, fertile part 2–15 mm long × 0.5–1.6 mm diam. (vs. fertile apex 0.5–1.2 mm long × 0.5–1 mm diam), and smaller ascospores (11.5–15 × 5.5–8 µm) with a straight germ slit ( Pan et al. 2022).

Figures

Figure 1. RAxML tree based on a combined ITS, TUB 2 and rpb 2 gene sequences data set. Bootstrap support values for maximum likelihood (ML) > 75 % and Bayesian posterior probabilities (BPP) > 0.95 are displayed above or below the respective branches (ML / BI). The newly described species are marked and red. Type materials were marked bold.

Figure 3. Xylaria nanningensis (GMB 4702) A type material B fertile part of stroma C surface of stroma D transverse section of stroma E longitudinal section of stroma F – H asci with ascospores I a J +, ascus apical apparatus (stained in Melzer’s Reagent) J – L ascospores M colonies of Xylaria nanningensis on OA. Scale bars: 0.5 mm (C – E); 10 µm (F – L).