Nemania phetchaburiensis Dayar., E.B.G. Jones & K.D. Hyde, in Dayarathne et al., Mycosphere 11(1): 165 (2020)

Index Fungorum number: IF 556602; MycoBank number: MB 556602; Facesoffungi number: FoF 06195; Fig. 1

Holotype – MFLU 16-1185

Saprobic on decaying submerged wood in freshwater. Sexual morph: Ascostromata 1–1.6 × 1.3–2.2 mm (x=1.3 × 1.9 mm, n=10), semi-immersed or superficial with immersed base, pulvinate to hemispherical, in clusters of up to 20 shiny, black, carbonaceous, stromata comprising plant cells and fungal hyphae. Ascomata immersed in stroma, subglobose to hemispherical, black, ostiolate, papillate. Peridium 80–130 µm wide, two-layered, outer, brown, thick-walled cells of textura angularis fusing at the outside with the pseudostromata, inner, pale brown, small elongate cells. Paraphyses 2–3 µm wide, filamentous, hyaline, septate, flexuous, branched, numerous and embedded in a gelatinous matrix. Asci 90–150×12–15 µm (x=120×13 µm, n=20), 8-spored, unitunicate, cylindrical, short pedicellate, wedge-shaped, J + subapical ring. Ascospores 14–16 × 6–9 µm (x=15×6.5 µm, n=20) overlapping uniseriate, light brown at immature stage, dark to greenish brown when mature, inequilaterally ellipsoid, ventral side varying in degree of convex curvature, upper and lower ends slightly pointed, one-celled, 1–2 guttules, germination slit usually clearly seen on the ventral side, straight, conspicuous. Asexual morph: Undetermined.

Culture characteristics – Colonies on PDA at 25 °C reaching 2 cm in 7 days, flat, circular, diffuse margins, white, wooly, reverse white, turn yellowish to light brown with time.

Material examined – China, Guangdong Province, Guangzhou City, Baiyun Mountain, on submerged decaying wood, 16 August 2021, Jizhen Fu, WBHS 1 (MHZU 22-0080, new geographical record), living culture ZHKUCC 22-0137.

Hosts and distribution – On decaying wood of Rhizophora sp. (Thailand), submerged wood of unidentified plant in China

GenBank numbers – ITS: OR164947, LSU: OR164959.

Notes – The sequence data of ITS, and LSU of our isolate (ZHKUCC 22-0137) gives species in Nemania as the closest matches with NCBI. Our isolate forms a well-supported clade (ML/BI=100%/1.00) with the ex-type strain of Nemania phetchaburiensis (Fig. 2). ITS and LSU sequences of our isolate are identical to the sequences derived from ex-type strain and morphological characters of our collection same to the holotype (Dayarathne et al. 2020). Therefore, we identified our collection as Nemania phetchaburiensis and this is the first record of this species in China.

Figure 1 – Nemania phetchaburiensis (MHZU 22-0080). a, b Ascomata on substrate. c Vertical cross section through ascoma. d Peridium. e Paraphyses. f J+apical ring. g–i Asci. j–o Ascospores. p Germinating ascospore. q Cultures on PDA from above. r Cultures on PDA from below. Scale bars: c=500 μm, d–f=5 μm, g–i=30 μm, j–p=15 μm

Figure 2 – Phylogram generated from maximum likelihood analysis based on combined ITS and LSU sequence data of 37 taxa, which comprised 1479 characters (ITS=612 bp, LSU=866 bp). The best scoring RAxML tree with a final likelihood value of − 8948.691975 is presented. The matrix had 590 distinct alignment patterns, with 10.36% of undetermined characters or gaps. Estimated base frequencies were as follows: A=0.233892, C=0.254026, G=0.301847, T=0.210236; substitution rates: AC=1.841685, AG=3.640707, AT=1.708445, CG=1.248451, CT=8.476357, GT=1.0; gamma distribution shape parameter α=0.583881. Bootstrap support for maximum likelihood (ML) equal to or greater than 50% and clade credibility values greater than 0.90 (the rounding of values to 2 decimal proportions) from Bayesian inference analysis are labelled at each node. Ex-type strains are in bold, while the new isolates are indicated in blue bold. The tree is rooted to Sporocadus trimorphus (CBS 114203)