Gnomoniopsis xunwuensis C.M. Tian & Q. Yang, sp. nov. 2020
MycoBank No: 829529
Holotype: China. Jiangxi Province: Ganzhou City, Xunwu County, 24°40'50"N, 115°34'37"E, on leaves of Castanopsis fissa, 12 May 2018, Q. Yang, Y. Liu & Y.M. Liang (holotype BJFC-S1688; ex-type living culture: CFCC 53115); 24°52'20"N, 115°35'25"E, on leaves of Castanopsis fissa, 12 May 2018, Q. Yang, Y. Liu & Y.M. Liang (BJFC-S1689; living culture: CFCC 53116 and CFCC 53117).
Morphological description
On PDA: Conidiomata pycnidial, (115–)130–210(–250) µm diam., globose, solitary to gregarious, or occasionally coalescing, deeply embedded in the medium, erumpent, brown to dark black. White to cream conidial drops exuding from the ostioles. Conidiophores (40–)43–58(–60.5) × 2–2.5(–3) µm, cylindrical, hyaline, phiailidic, branched or sympodially branched, straight or slightly curved. Conidia oval or fusiform, straight to slightly curved, hyaline, multiguttules, (14–)16.5–20 × 4–5.5 µm. Culture characters. Cultures incubated on PDA at 25 °C in the dark. Colony originally compact and flat with white aerial mycelium, then developing pale brown aerial mycelium at the center and blackish green mycelium at the marginal area, zonate with 2 well defined zones with regular edge; conidiomata dense, regularly distributed over agar surface.
Habitat: on leaves of Castanopsis fissa
Distribution: China
GenBank Accession: ITS CMK432667, MK432668, MK432669; tef1 MK578067, MK578068, MK578069; tub2 MK578141, MK578142, MK578143
Notes: Gnomoniopsis xunwuensis is associated with leaf spot of Castanopsis fissa, representing the first report from this host in China. It is characterized by sympodially branched conidiophore and oval or fusiform conidia. Morphologically, G. xunwuensis differs from G. daii in having bigger conidia (16.5–20 × 4–5.5 vs. 5.5–7 × 2–3.5 µm) (Jiang and Tian 2019). The phylogenetic inferences indicated this species as an individual well-supported clade (MP/ML/BI=100/100/1) in the genus Gnomoniopsis (Fig. 2).
Reference: Yang Q, Jiang N, Tian C-M (2020) Tree inhabiting gnomoniaceous species from China, with Cryphogonomonia gen. nov. proposed.
Gnomoniopsis xunwuensis on Castanopsis fissa (BJFC-S1688) A symptoms on leaves of host plant B the colony on PDA C conidiomata on PDA D, E conidiophores attached with condia F conidia. Scale bars: 500 µm (C); 20 µm (D–F).
