Epicoccum layuense Qian Chen, Crous & L. Cai, in Chen et al., Stud. Mycol. 87: 145 (2017)
Index Fungorum number: IF 818963; MycoBank number: MB 818963; Facesoffungi number: FoF 09381; Fig. 1
Holotype – HMAS 247165
Saprobic on dead stem of Heteropanax fragrans (Roxb.) Seem. Sexual morph: Undetermined. Asexual morph: Conidiomata 140–280 × 95–180 µm (x = 180 × 140 µm, n=20), sporodochia, scattered or aggregated, subglobose to globose, brownish to black. Conidigenous cells 2–6×2–4 µm (x = 4 × 3 µm, n = 10), short cylindrical, pale brown to blackish brown, smooth walled. Conidia 9–23×9–24 µm (x=18 × 20 µm, n=30), initially light-brown, becoming black-brown, multicellular-phragmosporous ellipsoid, subglobose to globose, verrucose.
Culture characteristics – Colonies on PDA reaching 5–6 cm diameter after 10 days at 25±2 °C, circular, margin entire, flat, with velvety, orange to umber, with aerial mycelia; reverse orange to reddish orange, pigment produced with age.
Material examined – China, Yunnan Province, Kunming City, from dead steam of Heteropanax fragrans (Araliaceae), 15 August 2020, C.F. Liao, (KUN–HKAS 112882, new host record), living culture KUMCC 21-0017.
Hosts and distribution – Perilla sp., Camellia sinensis, Oxalis corymbosa from China (Chen et al. 2020; Xie et al. 2022a), Vitis vinifera from Portugal (Del Frari et al. 2019), Weigela florida from China (Tian et al. 2021), Avena sativa from Northwestern China (Chen et al. 2020), Oxalis corymbosa from China (Niu et al. 2022), Oat from China (Chen et al. 2020).
GenBank numbers – ITS: OP575932, LSU: OP565037
Notes – Our isolate (KUMCC 21-0017) clustered with the type strain of E. layuense (CGMCC 3.18362) with ML/BI = 100/1.00 bootstrap support in the multigene phylogenetic analyses (Fig. 2). Epicoccum layuense was introduced by Chen et al. (2017) based on morphology and multigene phylogeny of ITS, LSU and β-tubulin sequences. The LSU sequence of our collection is identical to the LSU sequence of ex-type strain of Epicoccum layuense while ITS locus comprises one base pair difference. Morphological characters of our collection are very similar to the holotype (Chen et al. 2017). Therefore, considering morphology, phylogeny and similarity in sequences, we identified our collection as Epicoccum layuense.
Figure 1 – Epicoccum layuense (KUN-HKAS 112882). a, b Sporodochia on host substrate. c Sporodochium. d State. e–i Conidia. j, k Germinating conidia. l Surface view of colony on PDA. m Reverse view of colony on PDA. Scale bars: c=20 μm, d–i=10 μm
Figure 2 – Phylogram generated from maximum likelihood analysis based on combined ITS, LSU, β-tubulin and rpb2 sequence data which comprised 2321 characters (ITS=476, LSU=941, β-tubulin=333, rpb2=571). The best scoring RAxML tree with a final likelihood value of − 8757.729573 is presented. The matrix had 422 distinct alignment patterns, with 7.29% of undetermined characters or gaps. Estimated base frequencies were as follows: A=0.245371, C=0.247182, G=0.273997, T=0.233450; substitution rates: AC=1.183550, AG=3.903447, AT=1.6002, CG=0.898268, CT=11.877761, GT=1.0; gamma distribution shape parameter α=0.150149. 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 Leptosphaeria doliolum (CBS 616.75, CBS 505.75)