Montagnula lijiangensis Wanas., 2024

Wanasinghe, Dhanushka N., Nimalrathna, Thilina S., Qin Xian, Li, Faraj, Turki Kh., Xu, Jianchu & Mortimer, Peter E., 2024, Taxonomic novelties and global biogeography of Montagnula (Ascomycota, Didymosphaeriaceae), MycoKeys 101, pp. 191-232 : 191

Montagnula lijiangensis Wanas. sp. nov.

Fig. 6

Etymology.

The specific epithet “lijiangensis” refers to Lijiang, Yunnan Province, where the holotype was collected.

Holotype.

HKAS 126541.

Description.

Saprobic on dead woody litter of Quercus sp. Teleomorph Ascomata 500-700 μm high × 500-600 μm diam., immersed, gregarious or rarely clustered, globose to subglobose, ostiolate. Ostiole 100-140 × 80-120 µm (x- = 125 × 96 μm, n = 5), apapillate, central, straight, filled with hyaline cells. Peridium 20-30 μm thin on the sides and can reach up to 70 μm near the apex, with an outer layer consisting of heavily pigmented cells that have thick walls and exhibit a textura angularis texture at the apex, textura angularis texture at the sides and base; the innermost layer consists of narrow, hyaline compressed rows of cells. Hamathecium of 3-7.5 μm broad, dense, narrow, branched, cellular pseudoparaphyses that are swollen at the base. Asci 130-160 × 20-26 µm (x- = 152.8 × 23.9 μm, n = 20), bitunicate, fissitunicate, cylindrical-clavate to clavate, pedicel 30-60 μm long, 8-spored, uni to biseriate, with a minute ocular chamber best seen in immature ascus. Ascospores 22-26 × 10-14 µm (x- = 24.8 × 11.8 μm, n = 30), ellipsoidal to narrowly oblong, mostly straight, with conically rounded ends at the immature stage that become rounded when mature, golden-brown to dark brown, 1-septate and constricted at the septum, with large guttules in each cell, verruculose, surrounded by a thick mucilaginous sheath. Anamorph Undetermined.

Habitat and distribution.

This species is found in terrestrial habitats of Yunnan, China, inhabiting dead woody twigs of deciduous hosts (this study).

Material examined.

China, Yunnan Province, Lijiang , Yulong County (26.86389°N, 99.824738°E, 2725 m), on dead woody litter of Quercus sp. ( Fagaceae ), 17 August 2021, L. Qinxian, STX09-03-1 (holotype, HKAS 126541, ibid. 26.863484°N, 99.824548°E, 2706 m, STX09-03-3 (HKAS 126540).

Notes.

The analysis of two newly generated sequences revealed a monophyletic clade in our phylogenetic analysis (Fig. 1 ), demonstrating a close phylogenetic relationship to Montagnula aquilariae . This relationship is further supported by morphological features such as asci and ascospores. However, a comparison of nucleotide differences (without gaps) between these two clades (KUNCC 22-10815 and KUNCC 23-14430 vs HKAS 126541) showed 12/508 (2.3%) differences in the ITS region, 15/885 (1.7%) differences in the tef 1-α region, and 19/956 (2%) differences in the rpb 2 region.

Figures

Figure 1. Phylogenetic analysis of SSU, LSU, ITS, tef 1 - α, and rpb 2 of the Montagnula. Species names given in bold are ex-type, ex-epitype and ex-paratype strains. Species names highlighted in blue are generated from this study. Branch support of nodes ≥ 75 % ML BS and ≥ 0.95 PP is indicated above the branches. The genus Montagnula is depicted within a pale gray box, with new species highlighted in white, and the outgroup indicated by a blue box.

Figure 6. Montagnula lijiangensis (HKAS 126541, holotype) a, b ascomata on natural wood surface c vertical section through an ascoma d ostiolar neck and peridium cells at the apex e pseudoparaphyses f-i asci j-o ascospores (see verruculose feature of the ascospore in k). Scale bars: 100 μm (c); 20 μm (d, f-i); 10 μm (e-o).