Xylaria atrosphaerica Callan & J. D. Rogers, Mycotaxon
Creators: name: Wu, You-Peng
name: Pi, Yin-Hui
name: Long, Si-Han
name: Liu, Li-Li
name: Zhang, Xu
name: Long, Qing-De
name: Lin, Yan
name: Kang, Ying-Qian
name: Kang, Ji-Chuan
name: Wijayawardene, Nalin N.
name: Li, Qi-Rui
Publisher: name: Zenodo
Year: 2022
Subjects: Biodiversity
Taxonomy
Fungi
Ascomycota
Sordariomycetes
Xylariales
Xylariaceae
Xylaria
Xylaria atrosphaerica

description: Xylaria atrosphaerica (Cooke & Massee) Callan & J.D. Rogers, Mycotaxon 36 (2): 349 (1990) (Fig. 2)
Synonymy:
Hypoxylon atrosphaericum Cooke & Massee, Grevillea 22(no. 103): 68 (1894)
Penzigia atrosphaerica (Cooke & Massee) J.N. Mill., Monograph Univ. Puerto Rico, Series B 2: 212 (1934) Kretzschmaria atrosphaerica (Cooke & Massee) P.M.D. Martin, Jl S. Afr. Bot. 36(2): 79 (1970)
Kretzschmaria atrosphaerica (Cooke & Massee) P.M.D. Martin, Jl S. Afr. Bot. 42(1): 74 (1976)
MycoBank number: MB 127393
Saprobic on dead wood, forming on the host surface. Sexual morph: Stromata semiglobular or irregularly globose, pulvinate, 0.4‒1.8 mm high × 1.4‒3.2 mm broad (x = 1.4 × 2.3 mm, n = 10), with flattened or slightly convex top. Exterior grey dark to black, roughened by fine cracks and ostioles; interior whithish to light grey. Perithecia 0.3‒0.8 mm diam., completely immersed, sphaerical. Ostioles inconspicuous. Asci 182‒288 × 12.3‒20 μm (x = 237 × 16.1 μm, n = 30), unitunicate, 8-spored, cylindrical, long-stipitate, apically rounded, with a J+, wedge-shaped apical ring, blue staining in Melzer’s reagent, 7–12 μm (x = 10 μm, n = 30) high, 3.5–7 μm (x = 5.4 μm, n = 30) wide. Ascospores 20.5–25.5 × 6.5–10 μm (x = 22.7 × 7.8 μm, n = 30), brownish-black, unicellular, ellipsoid to inequilateral, with broadly rounded ends, smooth, with a sigmoid germ slit nearly half spore-length, lacking appendages and sheaths. Asexual morph: Undetermined.
Specimens examined: CHINA, Guizhou Province, Duyun City, Doupengshan Nature Reserve (26.223062°N, 107.22846°E), elev. 1086 m, on dead wood of unidentified plant, June 2021, Youpeng Wu, 2021DPS13 (GMB0077, KUN-HKAS 122633; living culture, GMBC 0077).
Culture characteristics: Colonies on OA reaching 4–5 mm diam. after 2 weeks at 25 °C. White at first, with regular margins, becoming moderately radiating furrows spreading toward the edge, medium becoming black from central; reverse greyish black ring in the center, white marginal area. After 4 weeks, colonies on OA reaching 9 cm diam., white, velvety, appressed with entire margins; reverse dark black. No conidia were observed.
Notes: Hypoxylon atrosphaericum Cooke & Massee collected from Queensland was described originally by Cooke (1894). Rogers et al. (1987) described the asexual morph of Penzigia atrosphaerica collected from Indonesia. However, based primarily on the nature of cultures, Callan & Rogers (1990) placed them in the genus Xylaria. Morphologically, our new collection (GMB0077) is congruent with X. atrosphaerica having semi-globular or irregularly globose stromata, grey dark to black, internally white; surface roughened by fine cracks and ostioles and perithecial mounds inconspicuous, brownish-black, ellipsoid-inequilateral, smooth ascospores (17–25 × 6–10 μm), with oblique to spiral germ slit, nearly 1/2 spore-length, lacking sheaths and appendages. Phylogenetic analyses showed that GMB0077 resembles with X. atrosphaerica (HAST 91111214) with high statistical support (100% ML, 1.00 BYPP; Fig. 1).
description: Published as part of Wu, You-Peng, Pi, Yin-Hui, Long, Si-Han, Liu, Li-Li, Zhang, Xu, Long, Qing-De, Lin, Yan, Kang, Ying-Qian, Kang, Ji-Chuan, Wijayawardene, Nalin N. & Li, Qi-Rui, 2022, Morphology and phylogeny reveal two novel Xylaria (Xylariaceae) species from China, pp. 130-146 in Phytotaxa 550 (2) on page 134, DOI: 10.11646/phytotaxa.550.2.3, http://zenodo.org/record/6641065