Pestalotiopsis diploclisiae Maharachch., K.D. Hyde & Crous, Stud. Mycol. 79: 140 (2014)
Index Fungorum number: IF 809737; MycoBank number: MB 809737; Facesoffungi number: FoF 10805;
Saprobic on Areca triandra rotting axis. Sexual morph: not observed. Asexual morph: Conidiomata stromatic, acervulus, erumpent, immersed under a host epidermal clypeus, raising host surface and producing a dark brown area of dehiscence, scattered. Conidiophores sparsely septate, unbranched or branched at the base, irregular, hyaline, up to 15 µm long. Conidiogenous cells 5 × 2 µm, discrete, smooth-walled, hyaline, sparsely verruculose, lageniform or sub-cylindrical. Conidia 16–25 × 5–6 µm (x̅ = 2.6 × 6 µm, n = 40), fusiform to ellipsoidal, 4-septate, straight to slightly curved; basal cell 3.5–6 µm long, conic with a truncate base, hyaline, minutely verruculose, thin- and smooth-walled; three median cells 10–15 µm long, x̅ = 14 µm, doliiform, smooth, concolourous, olivaceous, septa darker than the rest of the cell (second cell from the base 4–5.5 µm; third cell 3.5–5 µm; fourth cell 3.5–6 µm); apical cell 3–6 µm long, hyaline, conical to subcylindrical, smooth-walled; apical appendages 8–20 µm long, x̅ = 14.5 µm, 1–3 (most 2), tubular, arising from the apical crest, unbranched, filiform; basal appendage 4–8.5 µm long, single, tubular, unbranched, centric.
Culture characteristics – Colonies on PDA attaining 7 cm diam after 7 d at 25 ℃, erose, rotiform, rugose, white, undulate; reverse cream.
Material examined – China, Guangdong Province, Shenzhen City, Fairy Lake Botanical Garden, rotting tree axis of the Areca triandra, 30 November 2020, Y.R. Xiong, ZHKUCC 22–0010 (ZHKU 22–0009, new host record) – living culture in ZHKUCC; ibidem, 30 November 2020, Y.R. Xiong, ZHKUCC 22–0011 (paratype) – living culture in ZHKUCC; 30 November 2020, Y.R. Xiong, ZHKUCC 22–0012 (paratype) – living culture in ZHKUCC. CHINA, Guangdong Province, Guangzhou City, South China Botanical Garden, symptomatic lamina of Sabal mexicana, 17 June 2020, Y.R. Xiong, ZHKUCC 22–0024 (paratype) – living culture in ZHKUCC; 17 June 2020, Y.R. Xiong, ZHKUCC 22–0025 (paratype) – living culture in ZHKUCC.
Notes – In the present study three isolates obtained from Areca triandra clustered together with Pestalotiopsis diploclisiae with 72% ML values and 0.66 BYPP value. Pestalotiopsis diploclisiae was originally described from fruits of Diploclisia glaucescens and Psychotria tutcheri from China (Maharachchikumbura et al. 2014). Isolates obtained in this study are morphologically similar to the original description of P. diploclisiae (Maharachchikumbura et al. 2014). Therefore, based on morphology and new DNA data (Fig. 2), we identified P. diploclisiae isolates as a novel host record on A. triandra from China.
Figure Pestalotiopsis diploclisiae (ZHKU 22–0009). (a, b) Conidiomata on the rotting axis of Areca triandra; (c, d) Peridium; (e) Conidiogenous cells giving rise to conidia; (f–h) Conidia; (i) Germinating conidia; (j) Pycnidium; (k) The front view of a two-week-old colony on PDA; (l) The reverse view of a two-week-old colony on PDA; (m) The front view of a two-week-old colony on PDA from pathogenic samples; (n) The reverse view of a two-week-old colony on PDA from pathogenic samples; (o) Pycnidium from pathogen; (p) Conidiogenous cells giving rise to conidia; (q–s) Conidia from pathogen. Scale bars: c = 100 µm; d = 10 µm; e = 20 µm; f–i = 15 µm; p = 20 µm; q–s = 15 µm.