Pestalotiopsis neolitseae H.A. Ariyaw. & K.D. Hyde, Mycosphere 9(5): 1005 (2018)

Index Fungorum number: IF 827598; MycoBank number: MB 827598Facesoffungi number: FoF 04938;

Etymology – The specific epithet neolitseae is based on the host genus Neolitsea.

Pathogenic causing spots on leaves of Neolitsea villosa. Leaf spots circular to irregular, grey with brown margins when mature, or covering up to half of the leaf; dotted with acervuli. Sexual morph: undetermined. Asexual morph: Conidiomata on PDA pycnidial, globose or lenticular, solitary or aggregate, immersed or semi-immersed, exuding black slimy conidial mass on the surface of mycelia. Conidiophores often reduce to conidiogenous cells, when present, branched or unbranched. Conidiogenous cell discrete or integrated, cylindrical to subcylindrical, hyaline, smooth, often tapering to a neck on the septum of developing conidia, (6–)7–11(–13) × (2–)2–4(–5) μm, x̅± SD = 9 ± 2.2 × 3 ± 0.9 μm. Conidia ellipsoid, fusoid, straight to slightly curved, 4-septate, (15–)18–21(–25) × (4–)5–6 μm, x̅± SD = 20 ± 1.9 × 6 ± 0.4 μm; basal cell obconic, hyaline, smooth- and thin-walled, (3–)3–5(–6) μm long, x̅± SD = 4 ± 0.7 μm; three median cells doliiform, concolourous, pale brown, somewhat verruculose, (10–)11–14(–14) μm long, x̅± SD = 12 ± 1.2 μm (the second cell from base 3–4(–5) μm long, x̅± SD = 4 ± 0.4 μm; third cell 3–4(–5) μm long, x̅±SD = 4 ± 0.4 μm; fourth cell 4–5(–6) μm long, x̅± SD = 4 ± 0.4 μm), wall of the third and fourth cell from the base thicker than that of the second cell, septa darker than the rest of the cells; apical cell cylindrical to subcylindrical, conic to bell-shaped, hyaline, smooth- and thin-walled, (2–)3–4(–6) μm long, x̅± SD = 3 ± 0.5 μm; with 1–3 tubular apical appendages (mostly 2), arising from the apical crest, filiform, unbranched or branched, (7–)10–15(–17) μm long, x̅± SD = 13 ± 2.5 μm; basal appendage single, unbranched, straight to curved, centric or excentric, 2–5(–6) μm long, x̅±SD = 4 ± 0.9 μm.

Colony characteristics – Colony on PDA reaching 75mm diam after 6d at 25°C, circular, effuse with floccose texture, margin crenated and filamentous, colour white, with aerial mycelia on the surface, with immersed to semi-immersed conidiomata, producing black, glistening spore mass; reverse colour whitish pink, centre pale brown, margin pale honey–coloured, with black conidiomata.

Material examined Taiwan, Taipei Botanical Garden, Zhongzheng district, Taipei city, on leaf of Neolitsea villosa (Lauraceae) 9 August 2017, H. A. Ariyawansa, BG2.2 (NTUH 17-011; holotype) – ex–holotype living culture (NTUCC 17-011). ibid. (NTUH 17-012; paratype), ex-paratype living culture (NTUCC 17–012).

Distribution China

Sequence data – ITS: OK339744 (ITS1/ITS4); tef1: OK358505 (EF1-728F/EF2); tub2: OK358520 (Bt2a/Bt2b)

Notes Pestalotiopsis neolitseae is typical of Pestalotiopsis in having concolourous median cells and proposed here as a distinctive taxon-based phylogeny together with morphology (Figs 1, 3). Pestalotiopsis neolitseae differs from P. jinchanghensis in having smaller conidia (18–21 ×5–6 μm versus 22–32 × 5.5–8.5 μm), shorter apical appendages (10–15 μm versus 15–33.5 μm) and shorter basal appendages (2–5 μm versus 5.5–15.5 μm). Furthermore, Pestalotiopsis neolitseae differs from P. jinchanghensis by host (Neolitsea versus Camellia), and the geographical location (Taiwan versus mainland China).

Fig. 18. Morphology of Pestalotiopsis neolitseae (CFCC 54590). 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 = 200 μm; D–G = 10 μm.