Xylaria aleuriticola Hai X. Ma, A. H. Zhu & Yu Li, 2024

Zhu, An-Hong, Song, Zi-Kun, Wang, Jun-Fang, Guan, Hao-Wen, Qu, Zhi & Ma, Hai-Xia, 2024, Multi-gene phylogenetic and taxonomic contributions to Xylaria (Ascomycota) associated with fallen fruits from China, MycoKeys 106, pp. 23-41 : 23-41

Xylaria aleuriticola Hai X. Ma, A. H. Zhu & Yu Li sp. nov.

Fig. 2

Type.

China. Yunnan Province, Jinghong City, Xishuangbanna Primeval Forest Park , on buried fruits of Aleurites moluccana (L.) Willd ( Euphorbiaceae ), 22 October 2013, Ma HaiXia, FCATAS 858 (Col. 11) .

Etymology.

Aleuriticola (Lat.): referring to the host which the fungus inhabits.

Teleomorph.

Stromata upright or prostrate, solitary to often densely clustered, dichotomously branched several times, or unbranched infrequently, 2–11 cm total height, long-stipitate; fertile parts 7–30 mm high × 1.0– 2.5 mm broad, narrowly fusiform to cylindrical, often flattened, with acute sterile apices up to 8 mm long, strongly nodulose, particularly tomentose; stipes 12–90 mm high × 0.7–2.6 mm broad, terete to rarely flattened, most often contorted, usually ill-defined, with conspicuously tomentose, arising from a slightly enlarged pannose base; surface roughened with perithecial mounds and tomentose except for stromatal apices, black brown to black; interior white to cream, tan at center, solid, woody. Perithecia subglobose, 300–500 µm. Ostioles conic-papillate. Asci eight-spored arranged in uniseriate manner, cylindrical, long-stipitate, (90 –) 110–135 (– 150) µm total length, the spore-bearing parts (55 –) 60–70 (– 75) µm long × (5.5 –) 6.0–7.0 (– 7.5) µm broad, the stipes 30–70 µm long, with apical ring bluing in Melzer’s reagent, urn-shaped, 2.0–2.8 µm high × 1.0–1.8 µm diam. Ascospores brown to dark brown, unicellular, ellipsoid to fusiform, inequilateral, with narrowly rounded ends, occasionally one end slightly pinched, smooth, (7.1 –) 7.5–9.5 (– 10.5) × (3 –) 3.5–4 (– 4.5) µm (M = 8.1 × 3.6 µm, Q = 2.3, n = 60 / 2), with a conspicuous straight germ slit spore-length or slightly less than spore-length, lacking a hyaline sheath or appendages visible in india ink or 1 % SDS.

Additional specimen examined.

China. Yunnan Province, Jinghong City, Xishuangbanna Primeval Forest Park , on buried fruits of Aleurites moluccana ( Euphorbiaceae ), 22 October 2013, Ma HaiXia, FCATAS 859 (Col. 23); 22 January 2015, Ma Haixia, FCATAS 862 (Col. 231), FCATAS 863 (Col. 232), FCATAS 864 (Col. 238), FCATAS 865 ( COL. 270) .

Notes.

Xylaria aleuriticola , associated with the pericarps of A. moluccana ( Euphorbiaceae ), is characterized by stromata dichotomously branched several times with long acute sterile apices, fertile parts roughened with perithecia and tomentose, and tomentose stipes. It is similar to X. culleniae Berk. & Broome by having dichotomously branched stromata and ascospores dimensions, but the latter species branches dichotomously only once in fertile parts, ascospores surrounded with a hyaline sheath and non-cellular appendages, and grows on capsules of Cullenia excelsa ( Malvaceae ) ( Rogers et al. 1988; Ju et al. 2018). Xylaria euphorbiicola Rehm was described on fruits of Euphorbia ( Euphorbiaceae ) from Brazil, but it has unbranched stromata, lacking perithecial mounds, overlain with a brown striped outermost layer, and smaller discoid apical ring 1 µm high × 1.5–2 µm broad ( Ju et al. 2018). Xylaria ianthinovelutina somewhat resembles X. aleuriticola in stromatal morphology, but it has stronger stromata, larger ascospores (9 –) 9.5–11 (– 12) × (3.5 –) 4–4.5 (– 5) µm (M = 10.3 × 4.0 µm), and often associated with leguminous pods ( Dennis 1956, 1957; Ju et al. 2018), while stromata of the new speices has sharper and longer sterile apices, more forked. Xylaria luzonensis Henn. differs from X. aleuriticola by its smaller stromata (1.5–3 cm long × 0.5–1 mm diam), smaller perithecia (200–300 µm diam), slightly smaller apical ring (1–1.5 µm high × 1.5 µm broad), light brown ascospores, and grows on pod of Bauhinia cumingiana ( Fabaceae ) ( Ju et al. 2018). Xylaria apeibae Mont. is close to X. aleuriticola in stromatal morphology, from which it differs mainly by having smaller stromata 4 cm long × 0.8–1.5 mm diam, light brown and larger ascospores (9.5 –) 10–12 (– 13) × (3 –) 3.5–4 (– 4.5) µm (M = 11.0 × 3.7 µm), and grows on fruits of Apeiba species ( Tiliaceae ) ( Ju et al. 2018). In the phylogenetic analysis (Fig. 1 ), X. aleuriticola clustered together with high support values (BS = 98, PP = 1.00) with X. fabaceicola , but the latter species is distinguished by its smaller stromata 13–25 mm long, pale brown to brown ascospores with a hyaline sheath and appendages, and the fact that it grows on decaying pods of Fabaceae ( Perera et al. 2020) .

Figures

Figure 1. Phylogenetic tree of Xylaria based on the multigene alignment of ITS - RPB 2 - TUB 2 in the ML tree. ML bootstrap support (BS) ≥ 75 % and Bayesian posterior probabilities (PP) ≥ 0.90 are given at the nodes in this order. New species in this study are indicated in bold.

Figure 2. Xylaria aleuriticola (FCATAS 858, holotype) a, b stromata on fallen fruits c stromatal surface d, e section through stroma, showing perithecia f asci in Melzer’s reagent g asci in water h ascospores in Melzer’s reagent i ascal apical ring in Melzer’s reagent j, k ascospore in 1 % SDS l ascospore in India ink m ascospore with germ slit in India ink. Scale bars: 2 cm (a, b); 100 µm (c, e); 200 µm (d); 10 µm (f – m).