Paucispora xishanensis Aluth., Wanas. & K.D. Hyde, 2022

Aluthmuhandiram, Janith V. S., Wanasinghe, Dhanushka N., Chethana, K. W. Thilini, Gafforov, Yusufjon, Saichana, Natsaran, Li, Xing Hong, Yan, Jiye & Mamarakhimov, Oybek M., 2022, Lophiostomataceae (Dothideomycetes): Introducing Lophiostoma khanzadakirgizbaeva sp. nov. and Paucispora xishanensis sp. nov., Phytotaxa 559 (3), pp. 247-262 : 255

Paucispora xishanensis Aluth., Wanas. & K.D. Hyde , sp. nov.

Index Fungorum number: IF 558818; Facesoffungi number: FoF 10529; FIGURE 3 .

Etymology: The epithet reflects the district where the specimen was collected.

Saprobic on dead twigs of an unknown host. Sexual morph: Ascomata 200–340 μm high, 370–400 μm diam. (x̅ = 291 × 379 μm, n = 10), scattered to gregarious, immersed to semi-immersed, papilla erumpent through host surface, conical, flattened at the base, uni-loculate, coriaceous, black, ostiolate. Ostioles 120–140 μm high × 40–50 μm wide (x̅ = 131 × 44 μm, n = 5), slit-like, central, with a crest-like apex, broadly papillate, with a pore-like opening, filled with hyaline periphyses. Peridium 20–60 μm wide (x̅ = 39 μm, n = 20) at sides, wider at the apex, and thinner at the base, multi-layered, composed of 10–12 layers, outer layers composed of dark brown to black cells of textura angularis, indistinguishable from the host tissues, inner layer composed of hyaline cells of textura angularis. Hamathecium 1.2–1.7 µm (x̅ = 1.4 µm, n = 30) wide, composed with numerous dense, filiform, transversely septate, branched, anastomosing, cellular pseudoparaphyses situated between and above the asci, embedded in a gelatinous matrix. Asci 60–90 × 9–13 μm (x̅ = 77×11 μm, n = 30), 2–4-spored, bitunicate, fissitunicate, cylindric-clavate, apically rounded, with an ocular chamber. Ascospores 16–22 × 7–9 μm (x̅ = 20 × 8 μm, n = 50), uniseriate, partially overlapping, initially hyaline and turn dark brown at maturity, except pale end cells, ellipsoidal, straight, 1–3 septate, constricted at the central septum, widest at the region above or below the central septum, smooth-walled, guttulate, lacking a mucilaginous sheath. Asexual morph: Undetermined.

Material examined: Xishan , Kunming, Yunnan, China, Woody litter of unknown host plant, 19 July 2019. DN Wanasinghe, DW1344-4_1 ( HKAS 115905 , holotype) ; ibid. DW1344-4_2 ( HKAS 115906 , paratype)

Notes: In our phylogenetic analysis, Paucispora xishanensis ( HKAS 115905) groups basal to P. versicolor (MAFF 244508). Paucispora xishanensis ( HKAS 115905) is morphologically similar to P. versicolor (MAFF 244508) and P. kunmingense (MFLU 17-0558). However, P. xishanensis ( HKAS 115905) has depressed conical-shaped ascomata while P. versicolor (MAFF 244508) consists of globose to subglobose ascomata ( Hirayama et al. 2014; Thambugala et al. 2015) and P. kunmingense (MFLU 17-0558) consists of globose to depressed globose ascomata ( Hyde et al. 2017). Paucispora xishanensis ( HKAS 115905) and P. versicolor (MAFF 244508) both consist of 2-4 spored asci ( Hirayama et al. 2014; Thambugala et al. 2015), while P. kunmingense (MFLU 17-0558) consists of 4-spored asci ( Hyde et al. 2017). Paucispora xishanensis ( HKAS 115905) consists of initially hyaline ascospores, which turn dark brown at maturity, while P. versicolor (MAFF 244508) consists of brown to reddish-brown ascospores ( Hirayama et al. 2014; Thambugala et al. 2015) and P. kunmingense (MFLU 17-0558) consists of hyaline ascospores ( Hyde et al. 2017). In addition, the multilocus phylogenetic analyses also confirmed the phylogenetic placement of Paucispora xishanensis isolates HKAS 115905 and HKAS 115906 within the Paucispora clade as a phylogenetically distinct species with good statistical support (100 % ML-BS/1.00 BI-PP) ( FIGURE 1 ).

Figures

FIGURE 1. Maximum likelihood consensus tree inferred by IQ-TREE-ML analysis of combined SSU, ITS, LSU, tef1-α and rpb2 sequences alignment. Bootstrap support values for ML> 70%, and posterior probabilities for PP> 0.90 are given at the nodes (BS/PP). The tree is rooted with Teichospora trabicola (C134) and Teichospora rubriostiolata (TR7). Type species are shown in bold. Newly identified strains are in blue.

FIGURE 3. Paucispora xishanensis (HKAS 115905, holotype). a–c Appearance of ascoma on host surface. d Vertical section of ascoma. e Ostiolar canal. f Peridium. g Pseudoparaphyses. h–n Asci. o–s Ascospores. Scale bars: b, c = 400 µm, d, e = 100 µm, f–n = 20 µm, o–s = 10 µm.