Hydnotrya oblongispora L. Li & S.H. Li, sp. nov.

Li, Lin, Wan, Shan-Ping, Wang, Yun, Thongklang, Naritsada, Tang, Song-Ming, Luo, Zong-Long & Li, Shu-Hong, 2023, New species of Hydnotrya (Ascomycota, Pezizomycetes) from southwestern China with notes on morphological characteristics of 17 species of Hydnotrya, MycoKeys 100, pp. 49-67 : 49

Hydnotrya oblongispora L. Li & S.H. Li, sp. nov.

Plate 1

Diagnosis.

Differs from other species in the genus Hydnotrya by its nearly single-chambered ascomata and long ellipsoidal ascospores.

Etymology.

oblongispora, refers to the long ellipsoidal ascospores.

Holotype.

China, Yunnan, Lijiang (26°37.00'N, 99°42.00'E), alt. 3737 m, in the forest of Abies forrestii Coltm.-Rog, 12 August 2020, Lin Li, BMDLU L20069.

Description.

Ascomata irregularly globose, 1.0-2.5 cm in diameter when fresh, smooth, sometimes gently folded inward, surface light khaki (4C5) to reddish brown (8D8); nearly single-chambered with a primary apical opening up to 0.2-0.8 cm in diameter, sometimes the opening is just an almost closed seam, white fluffy inside cavity. Elastic and crisp. No special smell was noticed.

Peridium two-layered, 280-340 µm thick, outer layer 80-100 µm thick, composed of light brown (6D8) ellipsoidal or irregular cells, with a red brown (6E8) pigment deposited on the outermost cells; inner layer, 200-240 µm thick, consists of hyaline interwoven hyphae. Gleba chamber hollow, lined with a milky white (4B2) hymenium, hymenial surface fluffy. Asci cylindrical, 102.5-138.5 × 13.0-25.5 µm, 8-spored, thin-walled, narrowed into a long stalk (20-35 μm) at the base, without croziers, arranged in a palisade. Ascospore strictly uniseriate, long ellipsoidal, (20.0-) 26.5-39.0 × (9.5-) 11.0-21.5 μm, Q = 2.0 ± 0.03, hyaline when immature, golden yellow (5B7) when mature, with a thickened exosporium, surface pitted. Paraphyses hyaline, straight stick shape, 2.5-5 µm in diam, septate, exceeding the asci by 60-70 µm.

Ecology and distribution.

Hypogeous, solitary, or in groups in soil, under A. forrestii mixed with shrubs of Rhododendron spp., fruiting from late summer to early autumn. Known only from Yunnan Province, China.

Additional specimens examined.

China, Yunnan Province, Lijiang, Jiuhe , (26°38.00'N, 99°42.00'E), alt. 3946 m, in the forest of A. forrestii , 12.Aug.2020, Lin Li (BMDLU L20067 . GenBank: ITS = OM232075 , LSU = ON982626 ); same locality, 19.Sept.2021, Lin Li (BMDLU L21217 . GenBank: ITS = OM232084 , LSU = ON982625 ) .

Notes.

H. oblongispora is characterized by its mostly simple-chambered ascomata and golden yellow long-ellipsoid ascospores, especially with pitted surfaces, which differ from all other species of Hydnotrya. Molecular analysis also shows that H. oblongispora is distinct from other Hydnotrya species, although it is closely related to H. michaelis . However, H. michaelis has convoluted, lobed ascomata and broadly ellipsoid spores with warty ascospores, which differ from this new species.

Figures

Plate 1. Hydnotrya oblongispora A young sarcomata B mature ascomata with different openings C a piece of section of the ascomata in lactophenol cotton blue D a peridium section in lactophenol cotton blue E a section of paraphyses in 5 % KOH F a base of asci in lactophenol cotton blue G ascospores released from the ascus H asci in lactophenol cotton blue I an ascus with 8 ascospores J-L ascospores under SEM. Scale bars: 1 cm (A, B); 100 μm (C); 50 μm (D); 10 μm (E-I); 5 μm (J, L); 2 μm (K).