Nectria berberidis R.Ma & S.N.Li, 2020

Ma, Rong, Li, Sheng-Nan, Zhao, Ying, Wang, Min, Michailides, Themis J. & Tian, Cheng-Ming, 2020, New species of Nectria and Thyronectria from Xinjiang, China, Phytotaxa 433 (4), pp. 253-264 : 258-259

Nectria berberidis R.Ma & S.N.Li , sp. nov. Fig. 2 .

MycoBank: MB 830471

Holotype:— CHINA, Xinjiang Uygur Autonomous Region, Ili , Huocheng County, Fushou mountain , 44°25’37.94’’N, 80°47’17.31’’E, elev. 1182 m, on twigs of Berberis heteropoda Schrenk, R. Ma , 15 August 2017, (XJ-FPL 2433, living ex-type culture).

Etymology:— berberidis , named after Berberis heteropoda , the known host for this species.

Host/Distribution:—Twigs of Berberis heteropoda in northwestern China.

Original description:—Saprophytic on twigs of Berberis heteropoda . Sexual morph: mycelium not visible around the ascomata or on the host. Stromata erumpent through the epidermis, 1.4 mm high, 2.4 mm in diam., umber, becoming purple in KOH and yellow in LA, pseudoparenchymatous, cells forming textura angularis, intergrading with the ascomatal wall. Ascomata superficial, aggregated in groups of 4–22, sienna to umber, becoming dark purple in KOH and yellow in LA, subglobose to globose, slightly rough, 158–368 μm high and 206–555 μm in diam. Ascomatal wall 44–81 μm wide, composed of two regions: outer region 27–51 μm thick, intergrading with the stroma, cells forming textura globulosa or textura angularis, with pigmented walls about 2 μm thick; inner region 12–33 μm thick and composed of elongate, thin-walled, hyaline cells, forming textura prismatica. Asci clavate, increasing in size as the ascospores matured, eight-spored, biseriate above, uniseriate below, (50–)58–72(–87) × 8–12 μm (mean=65 × 10 μm, n=80). Ascospores ellipsoidal to fusiform, rounded at both ends, straight to slightly curved, hyaline, 1-septate, (12.3–)14.6–17.9(–20.8) × (3.1–)4.1–5.2(–5.9) μm (mean=16.3 × 4.6 μm, n=80). Asexual morph: Stromata erumpent through epidermis, orange to yellow brown. Sporodochial conidiomata superficial, well-developed stromata, smooth, scattered, solitary, astipitate, sessile, cerebriform or tuberculate, up to 210–450 μm high, 300–1000 μm wide, yellow to orange. Hymenium arising directly from textura prismatica, elongating from textura angularis, up to 72 µm long, not curved at margin. Conidiophores monoverticillate or sometimes biverticillate. Conidiogenous cells enteroblastic, monophialidic, cylindrical, straight or curved. Acropleurogenously developing phialides were intercalary, occurring below each septum, or terminal, 3.6–6.2 μm long, 1.0–2.2 μm wide at the base. Conidia hyaline, ellipsoidal to cylindrical, straight or slightly curved, non-septate, (7.8–)9.2–10.8(–12.4) × (2.2–)2.6–3.3(–3.9) μm (mean=10 × 3 μm, n=80).

Culture characteristics:—The mycelium of cultures grown on PDA at 25 °C, the mycelium appeared white initially. developed a pale-orange pigment after 5 days, aerial mycelium is white, not formed in concentric circles.

Specimens examined:— CHINA, Xinjiang Uygur Autonomous Region, Ili, Huocheng county , Fushou mountain , 44°26’07.91’’N, 80°47’24.53’’E, elev. 1188 m, on twigs of Berberis heteropoda Schrenk, R. Ma , 15 August 2017 (XJ-FPL 2423, paratype; living culture, XJAU 2423-1, XJAU 2423-2) .

Notes:—Molecular data show that N. berberidis forms a distinct clade with high support (MP/ML/BI=98/100/100), and is closely related to N. berberidicola and N. tibetensis . Both N. berberidis and N. berberidicola are collected from Berberis heteropoda , they can be distinguished by the size of asci (58–72 × 8–12 μm vs. 80–97 × 11–15 μm) ( Hirooka et al. 2012). Nectria berberidis differs from N. tibetensis by narrower ascospores (4.1–5.2 μm vs. 5–8 μm) ( Zeng et al. 2018).

Figures

FIGURE 2. Morphology of Nectria berberidis from Berberis heteropoda (XJAU 2433-1, XJAU 2433-2). A–B: Perithecia on natural substrata. C: Median section of perithecium. D–E: Asci. F: Ascospores. G: Colonies on PDA after 4 days (left) and 28 days (right). H: Sporodochium on natural substrate. I–J: Median section of sporodochium. K: Conidiophores. L: Conidia. M: Colonies on PDA after 4 days (left) and 28 days (right). Scale bars: A = 250 μm; B = 200 μm; C = 100 μm; D–F = 10 μm; H = 200 μm; I = 250 μm; J–K = 20 μm; L = 10 μm.