Apiospora gaoyouensis (C.M. Tian & N. Jiang) Pintos & P. Alvarado, Fungal Systematics and Evolution 7: 205 (2021)

Index Fungorum number: IF 837671; MycoBank number: MB 837671; Facesoffungi number: FoF 14206; Fig. 1

Holotype – BJFC S1411

Saprobic, isolated from dead twigs of Aster sp. Sexual morph: Ascomata 100–140 μm high, 98–110 μm diam. (x=126 × 108 μm, n=10), pycnidia, solitary or paired, scattered, immersed, globose to subglobose, dark brown to black, coriaceous, ostiolate, papillate. Peridium 10–15 μm wide, composed of several layers of dark brown cells of textura angularis. Hamathecium 4–5 μm wide, comprising dense, hyaline, septate paraphyses. Asci 75–90×18–22 μm (x = 86 × 20 μm, n = 20), 8-spored, unitunicate, clavate to fusiform, apically rounded, with an indistinct pedicel. Ascospores 17–22 × 8–11 μm (x = 20 × 10 μm, n = 30), overlapping uniseriate to overlapping biseriate, oval to fusiform, obtuse at both ends, slightly wider in the middle, hyaline, 1-septate, non-constricted at the septum, straight, apiosporous, large upper cell with 1–2-guttules, small lower cell mostly aguttulate, smooth-walled, sheath absent. Asexual morph: Sporulate on PDA after two weeks, scattered, dark brown conidial masses visible on cultures. Hyphae 2–4 μm diam., hyaline, branched, thick-walled, septate. Conidiophores reduced to conidiogenous cells. Conidiogenous cells 20–35 × 1.5–2.5 μm (x=25 × 2 μm, n = 25), holoblastic, monoblastic, hyaline, cylindrical, straight, discrete, aseptate, smooth-walled. Conidia dimorphic, 10–18×10–15 μm (x=11×12 μm, n=20), globose to subglobose, 7–10×18–21 μm (x=10×20 μm, n=25), elongated to pyriform, pale to dark brown, smooth-walled, with a longitudinal germ slit, wide pore at the ends of the slit. Sterile cells brown, elongated, mixed with conidia.

Culture characteristics – Colonies on PDA reaching 5 cm diam. after 7 days in dark at 25 °C, floccose, circular, edge entire, wooly aerial mycelia at the center, filamentous hyphae at the margin, initially white, becoming black when sporulate, reverse off-white.

Material examined – China, Guangdong Province, Guangzhou City, South China Botanical Garden (23° 11′ 12″ N 113° 21′ 51″ E), dead stem of Aster sp. (Asteraceae), 10 August 2021, I.C. Senanayake, S2 10-1 (MHZU 22-0076), living culture ZHKUCC 22-0133.

GenBank numbers – ITS: OR164907; LSU: OR164954; tef1-α: OR166283; β-tubulin: OR166325.

Notes – The sequence data of ITS, LSU, β-tubulin and tef1-α of our collection (MHZU 22-0076) gives species in Apiospora as the closest matches with NCBI. The phylogenetic analysis (Fig. 2) showed that our isolates clustered with type strain of Apiospora gaoyouense (CFCC52301, CFCC52302), with MP/BI=94%/1.00 support. Except the larger size of conidiogenous cells and conidia, our collection (MHZU 22-0076) is similar to Apiospora gaoyouense and it was occurred from dead stem of Aster sp., while A. gaoyouense collected from leaves and culms of Phragmites australis from China as a saprobe. Therefore, we identified our collection as A. gaoyouense and this is the first report on Aster sp. further, we described the sexual morph of A. gaoyouense for the first time.

Figure 1 – Apiospora gaoyouensis (ZKUH 22-0076). a Examined material. b Ascomata on substrate. c Vertical cross section of ascoma. d–f Asci. g–i Ascospores. j–m Conidiogenous cells attached to the conidia. n–p Conidia. q Upper view of culture on PDA. r Reverse view of culture on PDA. Scale bars: c=50 µm, d–i=20 µm, j–o=15 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)