Apiospora hainanensis R.Y. Liu, J.W. Xia & X.G. Zhang, 2023

Liu, Rongyu, Li, Duhua, Zhang, Zhaoxue, Liu, Shubin, Liu, Xinye, Wang, Yixin, Zhao, Heng, Liu, Xiaoyong, Zhang, Xiuguo, Xia, Jiwen & Wang, Yujiao, 2023, Morphological and phylogenetic analyses reveal two new species and a new record of Apiospora (Amphisphaeriales, Apiosporaceae) in China, MycoKeys 95, pp. 27-45 : 27

Apiospora hainanensis R.Y. Liu, J.W. Xia & X.G. Zhang sp. nov.

Fig. 3

Etymology.

Named after Hainan Province (China) where the type was collected.

Type.

China, Hainan Province: Diaoluoshan National Nature Reserve , on diseased leaves of bamboo, 23 June 2021, R.Y. Liu, holotype HSAUP 1681, ex-type living culture SAUCC 1681 .

Description.

Asexual morph: On WA, hyphae 1.2-3.4 μm diam., hyaline, branched, septate. Conidiophores cylindrical, septate, verrucose, flexuous, sometimes reduced to conidiogenous cells. Conidiogenous cells globose to subglobose, erect, blastic, aggregated in clusters on hyphae, hyaline to pale brown, smooth, branched, 6.4-8.8 × 5.2-7.1 μm, mean ± SD: 7.9 ± 1.1 × 6.1 ± 0.9 μm (n = 40). Conidia globose, subglobose to lenticular, with a longitudinal germ slit, occasionally elongated to ellipsoidal, brown to dark brown, smooth to finely roughened, 5.5-8.5 × 5.0-7.5 μm, mean ± SD: 6.8 ± 0.9 × 6.7 ± 0.7 μm, L/W = 1.0-1.1 (n = 40). Sexual morph: Undetermined.

Culture characteristics.

Colonies on PDA flat with entire margin, aerial mycelium white to grey, floccose cottony; reverse white to pale honey colored. PDA attaining 77.5-85.5 mm in diameter after 7 days at 25 °C, growth rate 10.5-12.5 mm/day.

Additional specimen examined.

China, Hainan Province: Diaoluoshan National Nature Reserve, on diseased leaves of bamboo, 23 June 2021, R.Y. Liu, paratype HSAUP 1682, ex-paratype living culture SAUCC 1682.

Notes.

The two strains (SAUCC 1681 and SAUCC 1682) of A. hainanensis clustered together with significant support in an isolated branch basal to A. sacchari and related species of the Arthrinium phaeospermum clade ( Pintos and Alvarado 2022; Fig. 1 ). Other species in a more or less similar phylogenetic position include A. septata (Y. Feng & Jian K. Liu) X.G. Tian & Tibpromma, A. piptatheri (Pintos & P. Alvarado) Pintos & P. Alvarado, A. longistroma (D.Q. Dai & K.D. Hyde) Pintos & P. Alvarado, A. pseudospegazzinii (Crous) Pintos & Alvarado and A. fermenti (S.L. Kwon, S. Jang & J.J. Kim) S.L. Kwon & J.J. Kim. Morphologically, it differs from A. septata , A. piptatheri , A. longistroma , A. pseudospegazzinii and A. fermenti in its conidia (globose, subglobose to lenticular, 5.5-8.5 × 5.0-7.5 μm in A. hainanensis vs. surface view globose to ellipsoid, 8-13 μm long and side view lenticular, 8-14 μm long in A. septata , globose to ellipsoidal, 6-8 × 3-5 μm in A. piptatheri , asexual morph undetermined in A. longistroma , surface view globose, 7-9 μm diam. and side view lenticular, 5-6 μm diam. in A. pseudospegazzinii , surface view globose to elongate ellipsoid, 7.5-9 × 7-9 μm and side view lenticular, 6-7 μm diam. in A. fermenti ; Crous and Groenewald 2013; Dai et al. 2016; Pintos et al. 2019; Feng et al. 2021; Kwon et al. 2021, 2022; Pintos and Alvarado 2021; Tian et al. 2021).

Figures

Figure 1. Phylogram of Apiospora based on combined ITS, LSU, tef 1 and tub 2 genes. ML bootstrap support values (MLBS ≥ 50 %) and Bayesian posterior probability (BYPP ≥ 0.90) are shown as first and second position above nodes, respectively. Strains from this study are shown in red, ex-type or ex-epitype cultures are indicated in bold face. Some branches were shortened according to the indicated mulipliers.

Figure 3. Apiospora hainanensis (SAUCC 1681, ex-holotype culture) a leaf of host plant b, c surface (b) and reverse (c) sides of colony after incubation for 7 days on PDA d conidiomata formed in culture e, f conidiogenous cells and conidia g, h conidia. Scale bars: 10 μm (e-h).