Pestalotiopsis foliicola N. Jiang, in Jiang, Voglmayr, Xue, Piao & Li, Microbiology Spectrum: 10.1128/spectrum.03272-22, 13 (2022)

Index Fungorum number:IF 843388; MycoBank number: MB 843388; Facesoffungi number: FoF 11694;

Etymology – folium = “leaf” and -cola = “inhabiting”; in reference to substrate origin of the type strain, leaves.

Pathogenic to host leaves. Asexual state: Conidiomata in culture sporodochial, aggregated or solitary, erumpent, pulvinate, black, 100–450 μm diam., exuding black conidial masses. Conidiophores indistinct, usually reduced to conidiogenous cells. Conidiogenous cells hyaline, smooth, cylindrical to ampulliform, annelidic, 6.5–20 × 2.5–6.5 μm, mean ± SD = 12.7 ± 4.2 × 3.1 ± 1.2 μm. Conidia fusoid, straight or slightly curved, 4-septate, smooth, slightly constricted at the septa, (19.5–)20–23(–24) × (7–)7.5–9(–9.5) μm, mean ± SD = 21.5 ± 1.5 × 8.5 ± 0.5 μm (n = 50), L/W = 2.1–2.9; basal cell obconic with a truncate base, thin-walled, hyaline or pale brown, (3–)3.5–5(–6) μm; median cells 3, trapezoid or subcylindrical, concolourous, pale brown to brown, thick-walled, the first median cell from base (4–)4.5–5.5(–6) μm long, the second cell (4–)4.5–5.5(–6) μm long, the third cell (3–)4.5–5.5(–6) μm long, together (10.5–)13.5–15.5(–16) μm long; apical cell conic with an acute apex, thin-walled, hyaline or pale brown, (2.5–)3–4(–4.5) μm long; basal appendage single, unbranched, tubular, centric, straight or slightly bent, (3–)3.5–4.5(–5) μm long, mean ± SD = 3.7 ± 0.7 μm; apical appendages 2–3, unbranched, tubular, centric, straight or bent, (10.5–)14–26(–37) μm long, mean ± SD = 20 ± 5.8 μm. Sexual morph unknown.

Culture characters – Colonies on MEA flat, with flocculent aerial mycelium and crenate edge, white, reaching a 35-mm diameter after 10 days at 25°C, sterile; on PDA, flat, spreading, with flocculent aerial mycelium and irregular edge, white to isabelline, reaching a 40-mm diameter after 10 days at 25°C, forming black conidiomata with black conidial masses.

Material examined – China, Jiangxi Province, Xinyu City, Fenyi County, Dagangshan Nature Reserve, on diseased leaves of Castanopsis faberi (Fagaceae), 13 November 2019, Shang Sun (holotype CAF 800045 = JNH0041; ex-holotype culture CFCC 54440); ibid., CFCC 57359 and CFCC 57360.

Distribution – China

Sequence data – ITS: ON007029 (ITS1/ITS4); tef1: ON005046 (EF1-728F/EF2); tub2: ON005057 (Bt2a/Bt2b)

Notes – Three isolates of Pestalotiopsis foliicola from Castanopsis faberi clustered into a distinct clade phylogenetically close to P. pinicola and P. rosea (Fig. 1). However, P. foliicola differs from P. pinicola and P. rosea by wider conidia (7 to 9.5 μm in P. foliicola versus 5 to 7 μm in P. pinicola and 5.7 to 7 μm in P. rosea) (25, 26).

Fig. 11. Morphology of Pestalotiopsis foliicola (CFCC 54440). A. Colony on PDA after 10 d at 25 °C; B. Colony on MEA after 10 d at 25 °C; C. Conidioma formed on PDA; D, E. conidiogenous cells giving rise to conidia; F, G. conidia. — Scale bars: C = 500 μm; D–G = 10 μm.