Xylaria karsticola J. Fournier & M. Stadler

Karimi, Omid, Thilini Chethana, K. W., Farias, Antonio R. G. & Li, Qirui, 2023, Two new records of Xylariales species from Northern Thailand, Phytotaxa 598 (3), pp. 187-205 : 193-198

Xylaria karsticola J. Fournier & M. Stadler , Mycological Progress 10(1): 40 (2011)

( FIGURES 1 and 3 )

Index Fungorum number: IF516640, Facesoffungi number: FoF 14033

Saprobic on Quercus kingiana .

Sexual morph: Stromata 10–60 mm height (x̄ = 27 mm, n = 20), upright to prostrate, often solitary to rarely clustered in small groups with the bases in contact, simple to branch, short-stipitate, fertile parts 6–45 × 1–1.5 mm (x̄ = 19.3 × 1.125 mm, n = 70), terete to rarely flattened, straight to most often sinuous to contorted, with short, pointed sterile apices, strongly nodulose with deep wrinkles isolating small to very small groups of perithecia, stipes 2–15 mm high × 1–1.2 mm broad, often ill-defined, black, puckered, downy to tomentose, arising from a pannose base, surface with a thin greyish to black peeling outer layer at immature state, turning dull black, outer stromatal crust 25–35 µm thick, leathery, finely longitudinally furrowed delimiting narrow dark grey strips, interior solid, dull black to cream-coloured. Perithecia 0.5–0.8 mm diam. (x̄ = 0.6 mm), semi-immersed to slightly prominent, spherical to depressed spherical. Ostioles 160–220 µm diam. (x̄ = 190 µm, n = 20), black, hemispherical to conical on a slightly raised discoid base. Asci 68–140 µm total length (x̄ = 101.5 µm, n = 50), the spore-bearing parts 49–67 µm × 3.5–5 µm (x̄ = 57.1 × 4.3 μm, n = 70), 8-spored, cylindrical, long stipitate, with tubular, apical apparatus, 1.3–2.83 × 1.08–2.7 µm (x̄ = 2.04 × 2 μm, n = 70), with a slightly flared apex bluing in Melzer’s reagent. Ascospores 7–8.8 × 3–5.2 µm (x̄ = 7.90 × 4.23 µm, n = 50), obliquely uniseriate, ellipsoid-inequilateral, often slightly pinched ends, dark olive-brown to dark brown, smooth, biguttulate, with inconspicuous, hyaline and a conspicuous straight germ slit of spore-length on the flattened side. Asexual morph: Undetermined.

Material examined: Thailand, Chiang Mai Province, Chomthong district, Doi Inthanon National Park , Kew Mae Pan nature trail, on decaying barks of Quercus kingiana (Fagaceae) , 18 October 2021, MC Samarakoon DI003, DI004 ( MFLU 23-0049 , MFLU 23-0050 , new host and geographical record) .

Known distribution: Southwestern France ( Fournier et al. 2011), The USA ( Thomas et al. 2016).

Known host: Quercus sp. on wood buried in karstic soil ( Fournier et al. 2011)

GenBank numbers: MFLU 23-0049: ITS = OQ457210, rpb2 = OQ597842, tub2 = OQ601533; MFLU 23-0050: ITS = OQ457211, rpb2 = OQ597841.

Notes – Morphologically, our collections resemble X. karsticola (MUCL 51695) in having simple to branch, upright to prostrate stromata with strongly nodulate, deeply wrinkled black surface, semi-immersed perithecia, hemispherical to conical black ostioles, long stipitate cylindrical asci, and uniseriate, ellipsoid-inequilateral, biguttulate ascospores, often slightly pinched ends with long germ slit. The phylogenetic analyses also showed that our collections grouped with X. karsticola (MUCL 51695, GA1A) with 100% maximum likelihood support and 1.00 Bayesian posterior probability ( Figure 1 ). We report our isolates (MFLU23-0049, MFLU23-0050) as a new geographical record from Thailand.

Figures

FIGURE 1. Phylogram generated from maximum likelihood analysis based on combined ITS, rpb2, and tub2 sequence data of the Xylariaceae. Maximum likelihood bootstrap support values greater than or equal to 60% and Bayesian posterior probabilities greater than or equal to 0.95 are given near nodes, respectively. The tree was rooted with Hypoxylon monticulosum (MUCL 54604), Hypoxylon trugodes (MUCL 54794), Daldinia loculatoides (CBS 113279), Hypoxylon fragiforme (MUCL 51264), Hypoxylon ticinense (CBS 115271), Barrmaelia rhamnicola (CBS 142772), Barrmaelia rappazii (CBS 142771), Entosordaria perfidiosa (EPE = CBS 142773) and Clypeosphaeria mamillana (CBS 140735). The newly generated sequences are indicated in blue.All the type specimens are in bold.

FIGURE 3. Xylaria karsticola (MFLU23-0049, new geographical record). a, b Stromata. c Section through the stroma. d–g Asci. h Apical ring stained in Melzer reagent. i–l Ascospores. Scale bars: b = 1 mm, c = 500 µm, d–f = 20 µm, h = 5 µm, i–l = 10 µm.