Montagnula aquilariae T.Y. Du & Tibpromma, Mycosphere 14 (1): 705 (2023)

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 aquilariae T.Y. Du & Tibpromma, Mycosphere 14 (1): 705 (2023)

Fig. 5

Description.

Saprobic on dead woody litter of an unknown deciduous host. Teleomorph Ascomata 450-600 μm high × 480-550 μm diam., immersed to semi-erumpent, gregarious or rarely clustered, globose to subglobose, ostiolate. Ostiole 120-220 × 70-110 µm (x- = 139 × 89 μm, n = 5), papillate, central, straight, dark brown to black, filled with hyaline cells, periphyses are lacking. Peridium 20-40 μm thick on the sides and can reach up to 60 μm near the apex, with an outer layer consisting of heavily pigmented cells that have thick walls and exhibit a textura angularis to textura globulosa texture at the apex, textura angularis texture at the sides and base; the innermost layer consists of narrow, hyaline compressed rows of cells that merge with pseudoparaphyses. Hamathecium of 2-4 μm broad, dense, narrow, branched, cellular pseudoparaphyses. Asci 100-120 × 16-22 µm (x- = 110.8 × 18.4 μm, n = 20), bitunicate, fissitunicate, cylindrical-clavate to clavate, pedicel 30-50 μm long, 8-spored, biseriate, with a minute ocular chamber best seen in immature ascus. Ascospores 20-25 × 8.5-11 µm (x- = 21.8 × 9.6 μm, n = 30), ellipsoidal to narrowly oblong, straight or somewhat curved, ends conically rounded, golden-brown to dark brown, 1-septate, constricted at the septum, large guttules in each cell, verruculose, with a thin mucilaginous sheath. Anamorph Undetermined.

Habitat and distribution.

This species is found in terrestrial habitats of Yunnan, China, specifically inhabiting dead woody twigs of deciduous hosts, including Aquilaria sinensis ( Hyde et al. 2023, this study).

Material examined.

China, Yunnan Province, Kunming City, Kunming Institute of Botany (25.141723°N, 102.750013°E, 1970 m), on dead woody litter of an unidentified plant, 24 April 2022, L. Qinxian, KIB22-17-1 (HKAS 126542), living culture KUNCC 23-14430 ; ibid. 25.141487°N, 102.748863°E, 1982 m, K2B22-17-3 (HKAS 126543), living culture KUNCC 23-14431 ; ibid. K2B22-17-4 (HKAS 126544), living culture KUNCC 23-14432 .

Notes.

Montagnula aquilariae was recently introduced by Hyde et al. (2023) based on samples obtained from Aquilaria sinensis in Xishuangbanna, Yunnan Province. In our new collections, three strains (KUNCC 23-14430, KUNCC 23-14431, KUNCC 23-14432) exhibited a monophyletic relationship with the previously known strains of Montagnula aquilariae (KUNCC 22-10815 [ex-type] and KUNCC 22-10816). Through further morphological, ecological, and nucleotide (SSU, LSU, ITS, tef 1-α) comparisons, we have confirmed that these new strains indeed belong to Montagnula aquilariae . Our research also provides additional insights into the characteristics of Montagnula aquilariae . Specifically, we report the verruculose feature of the ascospores and present rpb 2 sequence data for this fungus, advancing our knowledge of its morphological and genetic attributes.

Figures

Figure 5. Montagnula aquilariae (HKAS 126542) a, b ascomata on natural wood surface c vertical section through an ascoma d ostiolar neck e peridium cells at the apex f peridium cells at the side g pseudoparaphyses h-l asci m-r ascospores (see verruculose feature of the ascospore in r) s, t culture characters on PDA (s = above, t = reverse). Scale bars: 100 μm (c, d); 50 μm (e); 10 μm (e-g, m-r); 20 μm (h-l).