Pseudocoleophoma paraphysoidea Y. Feng & Z. Y. Liu, 2024

Feng, Yao, Liu, Zuo-Yi, Chen, Xiao-Fang, Yang, Mi-Lian, Zhang, Zhi-Yuan & Chen, Ya-Ya, 2024, Phylogeny and taxonomy of two new species in Dictyosporiaceae (Pleosporales, Dothideomycetes) from Guizhou, China, MycoKeys 106, pp. 251-264 : 251-264

Pseudocoleophoma paraphysoidea Y. Feng & Z. Y. Liu sp. nov.

Fig. 3

Etymology.

The epithet refers to the species having paraphyses.

Holotype.

GZAAS 21-0197 .

Diagnosis.

Saprobic on decaying wood in terrestrial habitats, and immersed in host epidermis. At maturity, the fruiting body breaks through host epidermis. Sexual morph: undetermined. Asexual morph: Conidiomata dark brown to black, pycnidial, solitary to gregarious, globose to subglobose, apapillate, ostiolate. Conidiomatal wall comprising several layers of cells of textura angularis, with inner layers comprising hyaline to dark brown and outer layers composed of dark brown to black cells. Conidiogenous cells 11–27 × 3–5 μm (av. 21 × 4 μm, n = 20), hyaline, enteroblastic, phialidic, with minute collarette, doliiform, ampulliform, arising from the innermost layer of the pycnidial wall, intermixed with hyaline, filamentous, septate paraphyses. Conidia 12–15 (- 23) × 2–4 μm (av. 14 × 3 μm, n = 30), hyaline, smooth, cylindrical to subcylindrical or fusiform, straight or slightly curved, aseptate, guttulate at both ends.

Culture characteristics.

Conidia germinating on WA within 12 h and germ tubes produced from the basal end. After transfer to the PDA, the colonies grew rapidly, reaching 5 cm diam. in 1 week at 25 ° C. Part of the mycelia grew on the surface of the medium, compact, violet, with a light-colored rim, and part of the mycelia remained immersed in the medium. The central area of the colony on the back was reddish-brown, the middle white, and the edge light-colored.

Material examined.

China, Guizhou Province, Guiyang City, Guizhou Academy of Agricultural Sciences , on dead culms of an unidentified plant, 18 June 2018, Zuo-Peng Liu, NK- 1 (holotype GZAAS 21-0197 , ex-type living culture GZCC 21-0711 ) . China, Guizhou Province, Xingyi City , on dead culms of an unidentified plant, 7 August 2019, Yao Feng XY 19-13 (paratype GZAAS 21-0198 , living culture GZCC 21-0712 ) .

Notes.

The multi-locus phylogenetic analyses showed that the new isolates GZCC 21-0711 and GZCC 21-0711 ( Pseudocoleophoma paraphysoidea ) formed a single clade and clustered together with high support value 81 / 0.94 (Fig. 1 ). Pseudocoleophoma paraphysoidea differs from P. bauhiniae in its conidiogenous cells intermixed with paraphyses, longer conidiogenous cells (11–27 × 3–5 μm vs. 2.5–5.5 × 2–3 µm) and larger conidia (12–15 × 2–4 μm vs. 7.5–11 × 2–3 µm) ( Jayasiri et al. 2019). In addition, they can be distinguished by their low sequence similarities. In a comparison of LSU, ITS, SSU, and tef 1 - α nucleotides, P. paraphysoidea (type strain GZCC 21-0711 ) has 99 %, 97 %, 99 % and 93 % similarity, in LSU (789 / 795 bp, no gap), ITS (490 / 503 bp, 2 gaps), SSU (1008 / 1010 bp, one gap), and tef 1 - α (815 / 878 bp, no gap), which is different from P. bauhiniae (Type strain MLFUCC 17-2586 ).

Figures

Figure 1. Phylogram based on the maximum likelihood (ML) analysis using the LSU, ITS, SSU, and tef 1 - α sequences of Dictyosporiaceae. Bootstrap support values for ML equal to or greater than 75 % and the Bayesian posterior probabilities equal to or higher than 0.95 PP are indicated above the nodes as ML / PP. Ex-type strains are in black bold and the new taxa are highlighted in bold and red.

Figure 3. Morphology of Pseudocoleophoma paraphysoidea (GZAAS 21-0197, holotype) A, B appearance of pycnidia on host C peridium D germinating conidium E paraphyses F, G culture H, I conidiogenous cells and conidia J – M conidia. Scale bars: 20 μm (C); 10 μm (D, H, I); 5 μm (J – M).