Nigrospora bambusae Mei Wang & L. Cai, in Wang, Liu, Crous & Cai, Persoonia 39: 127 (2017)

Index Fungorum number: IF 820800; MycoBank number: MB 820800; Facesoffungi number: FoF 14210, Fig. 1

Holotype – HMAS 246696

Saprobic, isolated from leaves of on twigs of Bambusa multiplex (Lour.) Raeusch. ex Schult. f. Sexual morph: Not observed. Asexual morph: Sporulate on PDA after four weeks, dark brown to black spore masses visible on cultures and host substrates. Hyphae 2–6 μm diam., initially hyaline, turn to olivaceous to pale brown with time, branched, thick-walled, septate. Conidiophores 18–25 × 2–4 μm (x = 20 × 3 μm, n = 25), straight, pale brown, aseptate, unbranched. Conidiogenous cells 5–10×1–2 μm (x=8×1.5 μm, n=25), holoblastic, monoblastic, hyaline, cylindrical, straight, discrete, aseptate, smooth-walled. Conidia 8–12×10–12 μm (x=10×10 μm, n = 20), dark brown, globose to subglobose, smooth-walled, with one or more longitudinal germ slits.

Culture characteristics – Colonies on PDA reaching 5 cm diam. after 5 days in dark at 20 °C, floccose, edge entire, initially white, becoming black when sporulate, reverse off-white with black patches due to sporulation.

Material examined – Thailand, Chiang Mai Province, Chiang Dao Mountain, leaves of Bambusa multiplex (Poaceae), 17 Febuary 2019, I.C. Senanayake, 46 (MHZU 22-0069), living cultures ZHKUCC 22-0126, ZHKUCC 22-0144.

Hosts and distribution – on bamboo leaves in China (Guangdong Province, Jiangxi Province) (Wang et al. 2017); on leaves of Bambusa multiplex in Thailand

GenBank numbers – ITS: OR164908, OR164909; LSU: OR164955, OR164956; tef1-α: OR166287; β-tubulin: OR166319, OR166320.

Notes – The sequence data of ITS, LSU, β-tubulin and tef1-α of our collection (MHZU 22-0069) gives species in Nigrospora as the closest matches with NCBI. The phylogenetic analysis (Fig. 2) showed that our collection is grouped with Nigrospora bambusae forming a clade with MP/BI=91%/0.95 statistical support. Our collection MHZU 22-0069 is morphologically similar to holotype of Nigrospora bambusae (Wang et al. 2017). Our collection obtained from Thailand on bamboo leaves.

Figure 1 – Nigrospora bambusae (ZKUH 22-0069). a Herbarium specimen. b Upper view of culture on PDA. c Reverse view of culture on PDA. d Conidial mass on substrate. e Hyphae. f–i Conidiogenous cells attached to the conidia. j Conidia. Scale bars: e–j=10 µm

Figure 2 – Phylogram generated from maximum likelihood analysis based on combined ITS, LSU, β-tubulin and tef1-α sequence data of 190 taxa, which comprised 2694 characters (ITS=565, LSU=862, β-tubulin=444, tef1-α=823). The best scoring RAxML tree with a final likelihood value of − 20,488.974413 is presented. The matrix had 917 distinct alignment patterns, with 25.57% of undetermined characters or gaps. Estimated base frequencies were as follows: A=0.229550, C=0.267919, G=0.242735, T=0.259795; substitution rates: AC=1.447018, AG=2.737139, AT=1.353872, CG=1.119023, CT=4.157776, GT=1.0; gamma distribution shape parameter α=0.215582. 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 isolate is indicated in blue bold. The tree is rooted to Sporocadus trimorphus (CBS 114203)

Figure 2 – (continued)

Figure 2 – (continued)