Ellipsoidisporodochium S.B. Liu, J.W. Xia & X.G. Zhang, 2022

Liu, Shu-Bin, Zhang, Zhao-Xue, Liu, Rong-Yu, Mu, Tai-Chang, Zhang, Xiu-Guo, Li, Zhuang & Xia, Ji-Wen, 2022, Morphological and molecular identification of Ellipsoidisporodochium gen. nov. (Tubakiaceae, Diaporthales) in Hainan Province, China, Phytotaxa 552 (4), pp. 259-266 : 262-263

Ellipsoidisporodochium S.B. Liu, J.W. Xia & X.G. Zhang , gen. nov.

MycoBank: 842196

Type species. Ellipsoidisporodochium photiniae S.B. Liu, J.W. Xia & X.G. Zhang

Etymology. Composed of “ellipsoidisporo-” (ellipsoid spores) and “-dochium” (referring to the conidioma, i.e., sporodochium).

Description. Asexual morph: mycelium consisting of septate, smooth and hyaline hyphae, thin-walled. Conidiomata sporodochial, appeared within 14 days or longer, formed on the agar surface, globose to subglobose, pale bluish-green in the center, with a layer of transparent conidia on the outside. Sporodochial conidiophores irregularly branched, tapering towards apex, swelling at base; sporodochial phialides monophialidic, fusoid to ampulliform, smooth, thin-walled. Conidia solitary, obovoid to ellipsoid, hyaline to subhyaline, guttulate, smooth, apex obtuse, base with inconspicuous to conspicuous hilum. Sexual morph: not observed.

Notes. In the phylogenetic trees ( Fig 1 ), Ellipsoidisporodochium is allied to Paratubakia and Oblongisporothyrium (BYPP = 1 and ML-BS = 98%) with well support, and forms a separate lineage with full support (BYPP = 1 and ML-BS = 100%), suggesting a genus of its own. In this study, E. photiniae was described from leaves of Photinia serratifolia in China. Based on the phylogenetic analyses using sequences of five genes (ITS, LSU, tef1, tub2 and rpb2), the new species is full supported (BYPP = 1 and ML-BS = 100%, Fig. 1 ) within Ellipsoidisporodochium and close to Oblongisporothyrium castanopsidis . In morphology and molecular data, the conidia of E. photiniae are smaller than those of O. castanopsidis (9–13 × 5–8 μm vs. 14–17 × 7–10 μm) and different nucleotides in the concatenated alignment (52/ 599 in the ITS, 9/ 858 in the LSU, 91/ 467 in the tef1, 49/ 520 in the tub2 and 116/ 897 in the rpb2).

Figures

FIGURE 1. Phylogram of Tubakiaceae based on combined ITS, LSU, tef1, tub2 and rpb2 genes. The BI and ML bootstrap support values above 0.50 BYPP and 60 % are shown at the first and second position above nodes. Strains from the current study are in red. Some branches were shortened to fit them to the page – these are indicated by two diagonal lines with the number of times a branch was shortened indicated next to the lines.