Tuber sinomacrosporum S. P. Wan, & F. Q. Yu 2023, sp. nov

Tuber sinomacrosporum S. P. Wan, & F. Q. Yu, sp. nov. (FIGURE 2) MycoBank: 846502 Typification: CHINA. Yunnan Province, Dali City (25° 38′ N , 100° 68′ E), in humic soil under a pure Pinus forest, at about 2090 m, 26 December 2020, wsp1043-8, YNAU016 (GenBank ITS number = OK625303). Diagnosis: Tuber sinomacrosporum is characterized by the brownish-red ascoma, mostly 1(2)-spored asci, large and ellipsoid ascospores. Etymology: referring to a Chinese species have large spores. Description: Ascoma 2.2 × 1.35 cm in diam, oval-shaped or irregular, light brown, partial brown to brownishred when fresh, becoming brownish-red when dried, surface partially covered with yellow tomentose. Odor pleasant. Peridium 108.0–148.0 μm thick, one layer, prosenchymatous, composed of yellowish to transparent cells and interwoven hyphae, cells (1.0–)2.2–5.7(–7.8) × (1.0–)1.7–4.5(–5.4) μm, hyphae 1.3–2.8 μm in diam. Gleba solid, blackish at maturity, marbled with different whitish to greyish veins continuous with the peridium; composed of hyaline, interwoven, thin-walled hyphae, 0.7–2.4 μm broad at the septa, the cells subglobose to globose, 1.1–7.3(– 10.5) × 0.9–5.7(–8.6) μm. Asci 114.0–143.0(–158.0) × 86.0–117.0(–124.0) μm, ellipsoid, rarely pyriform or irregular, hyaline, sessile or with a short or tall stalk 7.5–49.0 μm, 1-spored, rarely 2-spored. Ascospores ellipsoid, sometimes oblong elliptical and broadly ellipsoid, hyaline when young, becoming brownish-red to brown at maturity; excluding alveolar ornamentation, in 1-spored asci (80.0–)89.0–105.0(–109.0) × (55.0–)61.0–76.0(–78.0) μm (Q = 1.32–1.53, Q m = 1.43 ± 0.08) (n = 120), in 2-spored (51.0–)55.0–78.0(–84.0) × (32.0–)37.0–55.0(–57.0) μm (Q = 1.25–1.65, Q m = 1.4 ± 0.16) (n = 30). Ornamented with alveolate reticulum, 2–6 μm deep, constituted of irregularly polygonal meshes, reticulum with 3–7 meshes along the spore length and 3–7 across. Distribution and habitat: Hypogeous, in soil under pure stand of Pinus forest in Yunnan Province, China. Known only from China.
Published as part of Wan, Shan-Ping, Liu, Wei, Cui, Meng-Jin, Wang, Rui, Wang, Yu-Yun, Liu, Mei-Ju, Wang, Rui- Xue, Yu, Cheng-Jin & Yu, Fu-Qiang, 2023, Morphological and molecular evidence support a new truffle, Tuber sinomacrosporum, in Macrosporum group, pp. 283-291 in Phytotaxa 591 (4) on pages 286-288, DOI: 10.11646/phytotaxa.591.4.5, http://zenodo.org/record/7835575