Diaporthe goulteri R.G. Shivas, S.M. Thomps. & Y.P. Tan, Persoonia

Bundhun, Digvijayini, Senanayake, Indunil C., Jayawardena, Ruvishika S., Camporesi, Erio, Huang, Yinghua, Dong, Zhangyong, Hyde, Kevin D., Anun, Chaiwat To- & Cheewangkoon, Ratchadawan, 2021, First reports of the sexual morphs of Diaporthe forlicesenica nom. nov. and Diaporthe goulteri (Diaporthaceae, Diaporthales) revealed by molecular phylogenetics, Phytotaxa 516 (1), pp. 1-27 : 8

Diaporthe goulteri R.G. Shivas, S.M. Thomps. & Y.P. Tan, Persoonia 35: 43 (2015) amend. FIGURES 4 & 5

Index Fungorum number: IF808669, Facesoffungi number: FoF 09714

Saprobic on wood litter. Sexual morph: Ascomata 360–480 μm high, 145–280 μm diam. (x̅ = 420 × 210 μm, n = 15), perithecial, black, globose to conical, scattered to aggregated, deeply immersed in host epidermis, with elongated black necks emerging through host tissue, ostiolate. Neck 170–230 μm high, 45–70 μm diam. (x̅ = 190 × 55 μm, n = 15). Ostiole papillate, periphysate. Peridium 2-layered; outer layer 10–15 μm wide, heavily pigmented, composed of dark brown, thick-walled cells of textura angularis, inner layer 10–20 μm wide, comprising light brown to hyaline, thin-walled cells of textura angularis. Paraphyses 4–5 μm wide, hyaline, septate, wider at the base, thin-walled. Asci 30–50 × 5–10 μm (x̅ = 39.1 × 7.4 μm, n = 30), unitunicate, 8-spored, sessile, broadly cylindrical to sub-obclavate, thin-walled, apically rounded, with a J-, apical ring, straight to slightly curved. Ascospores 7–10 × 2–4 μm (x̅ = 8.8 × 2.4 μm, n = 30), overlapping uniseriate to bi- or tri-seriate, hyaline, 1-septate, regularly 4-guttulate, with the two larger guttules at the center and smaller ones at the ends, fusiform to elliptical, straight, smooth-walled, lacking any appendage or mucilaginous sheath. Asexual morph: Coelomycetous. Conidiomata up to 600 μm high and 900 μm in diam., erumpent to superficial on PDA, pycnidial to multilocular, scattered to aggregated, globose to irregular, black. Conidiophores 15–20 × 2–3 μm (x̅ = 18.4 × 2.1 μm, n = 20), originating from the innermost layer of the locular wall, 1-septate or reduced to conidiogenous cells, hyaline, filiform, smooth-walled. Conidiogenous cells 3–8 × 1–2 μm (x̅ = 5 × 1.5 μm, n = 20), cylindrical, straight to flexuous, tapering towards the apex, hyaline. Alpha conidia 5–8 × 2–3 μm (x̅ = 6.9 × 2.1 μm, n = 30), produced in abundance, fusiform to cylindrical, rounded to slightly obtuse at the ends, hyaline, smooth-walled. Beta conidia 15–20 × 1–2 μm (x̅ = 17 × 1.4 μm, n = 20) few, filiform, hooked, aseptate, hyaline, smooth-walled. Gamma conidia not observed.

Culture characteristics:—Colonies on PDA, reaching 35 mm diam. after 1 week at 25 °C, flat, irregular, with a smooth surface, entire margin, off-white to buff, reverse buff. Sporulation occurred on PDA after 30 days incubation period at 25 °C, in dark.

Material examined:— THAILAND, Chiang Rai Province, Mae Fah Luang , on a dead branch of an unknown host, 11 May 2019, D. Bundhun, DB150 ( MFLU 21-0022 ), living culture MFLUCC 21-0012 .

Notes:— Diaporthe goulteri was introduced and described by Thompson et al. (2015) in its asexual morph. In the present study, an isolate of Diaporthe (MFLUCC 21-0012) clustered with the strain of D. goulteri (BRIP 55657a) with strong statistical support (100% ML, 1.00 BYPP) (FIGURE 1). The insignificant differences in base pairs in the ITS, tef1 and tub2 sequence data for the two strains (<1.5%) support them as a single species ( Jeewon & Hyde 2016). Moreover, the asexual morph produced in culture (FIGURE 5) also corroborates with the morphology in Thompson et al. (2015). The minor differences in size of the morphological characters may be accounted for by environmental variations. To supplement the observation of Thompson et al. (2015), beta conidia of D. goulteri have also been observed in culture in the present study. However, the attachment of these conidia on the conidiophores could not be easily observed. Thus we were unable to get a clear photograph of the attachment.