Neopyrenochaeta triseptatispora Mapook & K.D. Hyde, 2020

Rathnayaka, Achala R., Chethana, K. W. Thilini, Tennakoon, Danushka S., Lumyong, Saisamorn & Hyde, Kevin D., 2021, Additions to the microfungi in Taiwan: introducing Pseudorobillarda camelliaesinensis sp. nov., (Pseudorobillardaceae) and new host records of pleosporalean taxa in mountainous habitats, Phytotaxa 516 (2), pp. 115-139 : 125-127

Neopyrenochaeta triseptatispora Mapook & K.D. Hyde , Fungal Diversity 101: 63 (2020)

Index Fungorum number: IF557314; Facesoffungi number: FoF 07802; FIGURE 6 .

Saprobic on dead branch of Sambucus formosana Nakai. Sexual morph: Ascomata 95–105 μm high × 107–125 μm diam. (x̄ = 100 × 112 μm; n = 10), semi-immersed, appearing as, small dark spots, coriaceous, solitary or scattered, globose to sub-globose, reddish brown to brown. Peridium 7–12 μm wide, comprising hyaline or pale brown to brown cells of textura angularis. Hamathecium comprising 1–3 μm wide, cylindrical, septate, unbranching pseudoparaphyses. Asci 35–55 × 10–15 μm (x̄ = 47 × 12 μm; n = 20), 8-spored, bitunicate, fissitunicate, cylindric-clavate, straight or slightly curved, with a short bulbous pedicel, apically rounded. Ascospores 15–22 × 4–7 μm (x̄ = 18 × 6 μm; n = 30), overlapping, 2–3-seriate, hyaline to pale brown, cylindric-fusiform to inequilateral, with obtuse ends, slightly widest at the second cell from the apex and tapering towards the rounded ends, 3–4 septate, straight or slightly curved, with small guttules, constricted at the septa. Asexual morph: Undetermined.

Culture characteristics: Ascospores germinated on PDA within 24 hours, germ tube produced from several cells. Colonies on PDA, reached up to 2–3 cm diam. after 1 weeks at 25 °C, circular, colony from above: flat mycelium, filamentous, initially white, gradually becoming grey colour; from below: dark grey colour.

Material examined: Taiwan, Alishan Mountain, on dead branch of Sambucus formosana (Adoxaceae) . 16 August 2019, Achala Rathnayaka (MFLU 21-0008, new host record); living culture NCYUCC 19-0402.

Known Distribution: Thailand ( Mapook et al. 2020, Taiwan (this study)

GenBank accession numbers: LSU: MW478593 , ITS : MW478597 , rpb 2: MW478493

Notes: Our collection (NCYUCC 19-0402) is similar to the holotype of Neopyrenochaeta triseptatispora (MFLU 20-0340) collected from dead stems of Chromolaena odorata in Thailand ( Mapook et al. 2020) in having reddish-brown to brown ascomata, cylindric-clavate asci and hyaline ascospores with wider second cell from the apex ( Mapook et al. 2020). However, NCYUCC 19-0402 differs from Neopyrenochaeta triseptatispora (MFLU 20-0340) by lacking setae, having unbranched pseudoparaphyses and ascospores with 3–4 septa. These morphological changes can be because of the environmental variations of two different sites in different countries. Holotype of Neopyrenochaeta triseptatispora was reported from Chromolaena odorata plants in Doi Pui, Thailand while, our collection (NCYUCC 19-0402) is from Sambucus formosana hosts in Alishan Mountain, Taiwan. According to the molecular phylogenetic analyses, our strain revealed 1.25% (5/405) base pair difference in rbp2, with the ex-type of N. triseptatispora (MFLUCC 17-1436). Our strain grouped with the ex-type of Neopyrenochaeta triseptatispora (MFLUCC 17-1436) with 100% ML and 1.00 PP statistical support ( FIGURE 2 ). This is the first record of Neopyrenochaeta triseptatispora on Sambucus formosana and the first geographical record from Taiwan.

Figures

FIGURE 2. Phylogenetic tree generated from ML analysis based on combined dataset of LSU, ITS and rpb2. Related sequences were obtained from GenBank and Mapook et al. (2020). The tree is rooted to Stemphylium vesicarium (CBS 191.86 and MFLUCC 13-0344). Bootstrap support values for ML ≥ 70% and Bayesian posterior probabilities (PP) ≥ 0.95 are noted at the nodes. Strain numbers are mentioned at the end of the species name. New isolate used in this study represented as blue bold and type strains are in bold.

FIGURE 6. Neopyrenochaeta triseptatispora (MFLU 21-0008,new hostrecord) ondead branch ofSambucus formosana.aAppearanceof ascomata on host substrate.b Close-up of ascomata.c Vertical section through an ascoma.d Section through peridium.e Pseudoparaphyses. f–i Asci. j–n Ascospores. o Germinating ascospore. p Colony from above. q Colony from below. Scale bars: a =500 μm, b = 100 μm, c = 50 μm, d, e = 5 μm, f–o = 10 μm.