Ampelomyces quisqualis Ces.

Bundhun, Digvijayini, Jones, E. B. Gareth, Jayawardena, Ruvishika S., Camporesi, Erio, Wanasinghe, Dhanushka N., Senanayake, Indunil C., Thiyagaraja, Vinodhini & Hyde, Kevin D., 2024, Taxonomic novelty in Pleomonodictydaceae and new reports for Ampelomyces quisqualis (Phaeosphaeriaceae), Melomastia maolanensis and M. oleae (Pleurotremataceae), MycoKeys 111, pp. 147-180 : 147-180

Ampelomyces quisqualis Ces. , in Klotzsch, Bot. Ztg. 10: 301 (1852)

Fig. 5

Description.

Saprobic on stem of Sonchus sp. Sexual morph: Ascomata 140–180 µm high, 200–260 µm diam. (x – = 159 × 221 µm, n = 5), immersed, appearing as black dots on the host surface, solitary to aggregated, scattered, perithecial, unilocular, globose to subglobose, dark brown, ostiolate. Ostiole centric, comprising hyaline cells. Peridium 20–30 µm thick near the ostiole, 10–25 µm wide at the sides and 10–20 µm thick at the base, 3–4 - layered, outer layer made up of thick-walled, brown cells of textura angularis; inner layer made up of thin-walled, pale brown to hyaline cells of textura angularis. Pseudoparaphyses 1–1.5 µm wide, numerous, hyaline, filiform, branched, septate, cellular, usually guttulate, surrounding the asci. Asci 45–65 (– 68) × 5–7.5 µm (x – = 56.7 × 6.4 µm, n = 40), bitunicate, 8 - spored, cylindrical, straight to slightly curved, thin-walled, short-pedicellate, bulbous, with an apical ocular chamber. Ascospores 12–17 × 2–4 µm (x – = 15.3 × 3 µm, n = 50), overlapping uni- to bi-seriate, hyaline when immature, sub-hyaline on maturity, fusiform, straight to slightly curved, 2 - celled with a median septum, symmetrical or upper cell slightly longer than lower cell, cell above septum slightly enlarged and with round or conical ends, lower cell mostly with round ends, minutely guttulate, sometimes both ends containing hyaline appendages which disappear with age. Asexual morph: see Manjunatha et al. (2020).

Material examined.

Italy • Forlì-Cesena , Valico Tre Faggi - Premilcuore; on dead aerial stems of Sonchus sp. , 22 Jun 2021, E. Camporesi IT 4713, Herbarium material MFLU 23-0142 .

Notes.

Phylogenetic analyses based on the combined LSU – ITS dataset showed that strain MFLU 23-0142 grouped with Ampelomyces quisqualis (AMP, Chillan, BRIP 72107, and CBS 133.32) strains with 100 % ML BS, 1.00 BYPP support (Fig. 2 ). While there was no base pair (bp) difference among the three strains of A. quisqualis (Chillan, BRIP 72107 and CBS 133.32) and MFLU 23-0142 vis-à-vis the ITS sequence (based on the aligned untrimmed dataset, including gaps), 1.2 % (6 / 518 bp) difference between A. quisqualis (AMP) and strain MFLU 23-0142 was observed. Similarly, there was 0.1 % bp (1 / 876 bp) difference between A. quisqualis (CBS 133.32) and MFLU 23-0142 with regards to the LSU sequence (no LSU sequence data are available for strains AMP, Chillan, and BRIP 72107 in GenBank). A morphological comparison could not be made since our strain was collected in its sexual morph while Ampelomyces has so far been reported in its asexual morph. Therefore, the strain MFLU 23-0142 is described as the sexual morph of A. quisqualis based on phylogenetic support.

Figures

Figure 2. Phylogenetic tree generated from RaxML analysis, based on LSU – ITS matrix for Ampelomyces. The evolutionary model GTR + I was applied for LSU, while GTR + I + G was the best-fit model for ITS. The BYPP analysis was run for 1 million generations. The tree is rooted with Neosetophoma lonicerae (KUMCC 18-0155). Maximum likelihood bootstrap, ML BS (≥ 60 %), and BYPP (≥ 0.95) supports are shown above the branches, respectively. The type strain is in bold, and the newly collected strain is in bold red. TreeBASE submission ID: 31444.

Figure 5. Ampelomyces quisqualis (MFLU 23-0142) a ascomata on host substrate b vertical section of an ascoma c section of an ostiole d peridium e pseudoparaphyses f – h asci i – m ascospores n – p hyaline appendages at both ends of ascospores (shown by arrows). Scale bars: 100 µm (b); 50 µm (c); 10 µm (d, i – p, ); 3 µm (e); 30 µm (f – h).