Cytospora gigaspora C.M. Tian, X.L. Fan & K.D. Hyde, 2015

Fan, Xin-Lei, Hyde, Kevin D., Yang, Qin, Liang, Ying-Mei, Ma, Rong & Tian, Cheng-Ming, 2015, Cytospora species associated with canker disease of three anti-desertification plants in northwestern China, Phytotaxa 197 (4), pp. 227-244 : 232-233

Cytospora gigaspora C.M. Tian, X.L. Fan & K.D. Hyde , sp. nov. ( Fig. 3 )

MycoBank MB 806044, Facesoffungi number: FOF00303

Differs from Cytospora nivea in flat locules and larger conidia size (8.1–)8.9–12.1(–13.5) × (1.7–)1.9–2.9(–3.3) μm, average in 10.4 × 2.2 μm.

Holotype:— BJFC-S975 .

Host and Distribution:—Known from Salix psammophila in China.

Etymology:— gigaspora (Lat.) , referring to the unusual large size of conidia.

Pathogen on twigs and branches of Salix psammophila . Sexual state:—Unknown.

Asexual state:—Stromata immersed in bark. Conidiomata, slightly erumpent through the surface of bark, discoid, nearly flat, with multiple small locules. Conceptacle dark, surrounding the stromata. Disc white to light brown, circular to ovoid, (90–)110–150(–180) μm (average = 130 μm, n = 20) in diameter, with one ostiole per disc. Ostiole in the center of the disc, inconspicuous, at the same level as the disc surface, area below disc a lighter entostroma, (12.6–)13.2–17.1(–19.3) μm (average = 15.6 μm, n = 20) in diameter. Multi-locules arranged irregularly with common walls, (540–)670–810(–890) μm (average = 730 μm, n = 20) in diameter. Conidiophores hyaline, unbranched or occasionally branched at the bases, (9.4–)12.5–19.7(–20.8) μm (average = 15.5 μm, n = 20). Conidia hyaline, elongate-allantoid, eguttulate, aseptate, (8.1–)8.9–12.1(–13.5) × (1.7–)1.9–2.9(–3.3) μm (average = 10.4 × 2.2 μm, n = 50).

Cultures:—colony originally white, and producing dark green to black pigment after 7–10 days, flat and thin, with a uniform texture, conidiomata irregular on medium surface.

Material examined:— CHINA Shaanxi Province: Yulin, Jichang East Road , 38°19’21.16” N, 109°39’54.73” E, 1124 m asl., on twigs and branches of Salix psammophila , collected by X. L. Fan, 1 Aug 2013 ( BJFC-S975 , holotype) ; living culture, CFCC 89634 , CCTCC AF2013031 ; Shaanxi Province: Yulin, Hongshi Gorge , 38°19’32.43” N, 109°42’00.69” E, 1105 m asl., on twigs and branches of Salix psammophila , collected by X. L. Fan, 29 Jul 2013 ( BJFCS979 , paratype) ; living culture, CFCC 89635 , CCTCC AF2013032 .

Figures

FIGURE 3. Morphology of Cytospora gigaspora from Salix psammophila (BJFC-S975, holotype). a, d: Habit of conidiomata on a twig. b, c: Longitudinal sections through conidiomata. e, f: Transverse sections through conidiomata. g: Conidiophores. h: Conidia. i: Colonies on PDA at 3 days (left) and 30 days (right). Scale bars: a = 1 mm; b–f = 0.5 mm; g = 20 μm; h = 5 μm.