Gautieria mianjin Kun L. Yang, Xiao Liu & Zhu L. Yang, 2023

Yang, Kun L., Yang, Zhu L., Zhang, Ming, Wang, Geng-Shen & Liu, Xiao, 2023, Gautieria mianjin (Gomphales, Basidiomycota), a new species of false truffle from China, Phytotaxa 594 (2), pp. 119-129 : 123

Gautieria mianjin Kun L. Yang, Xiao Liu & Zhu L. Yang , sp. nov. ( Figs. 1 and 2 )

Mycobank No.: MB847194

Etymology: —The epithet refers to a kind of traditional Chinese food, named “mianjin”. Mianjin is made from gluten, irregularly subglobose and honeycomb-like in shape, and has a thin film on surface present when raw, easily broken when cooked, sharing a strong resemblance to the basidioma of this fungus.

Diagnosis: — Gautieria mianjin is similar and close to G. xinjianensis , but differs from the latter by its subglobose to broadly ellipsoid basidiospores mainly measured 11–14×10–12 μm with 10–14 longitudinal ribs.

Type: — China, Gansu Province, Gannan Tibetan Autonomous Prefecture, Lintan County, Yeliguan Town, 34°55′ N, 103°39′ E, on soil in temperate forests dominated by plants of Larix and Picea , altitude 2600 m, October 11, 2022, Xiao Liu 001 ( HKAS126926 , holotype! ; Kun-Long Yang’s private herbarium HTBM0250 , isotype!) .

Basidioma with pleasant aroma, emergent, irregularly subglobose, 2.5–5 cm in diameter. Peridium practically absent. Gleba brain-like to honeycomb-like; tramal plates 400–500 μm thick, milky white (C4 M3 Y2 K0), slightly gelatinous, covered with sandy yellow (C0 M10 Y50 K10), earthy yellow (C10 M40 Y70 K10) to mummy brown (C0 M50 Y70 K40) spore mass; columella indistinct, very slender and sometimes the same thick as the tramal plates, emanating from the base and frequently branching; locules irregularly shaped, labyrinthine. Basal rhizomorph whitish (C0 M1 Y5 K0).

Basidiospores subglobose to broadly ellipsoid, light brown (C30 M40 Y60 K0) in KOH, with 10–14 longitudinal ribs, sometimes branching or with cross veins in between, (10) 11–14 (16) [12.24 ± 1.20] × (9.5) 10–12 (13) [10.96 ± 0.77] μm, Q = (1.00) 1.04–1.24 (1.26) and Q m = 1.12 ± 0.07 including ribs, (9) 10–12 (15) [11.53 ± 1.36] × (8) 9–10 (11) [9.33 ± 0.69] μm, Q = (1.05) 1.15–1.33 (1.43) and Q m = 1.23 ± 0.10 excluding ribs; apiculus 1–2 (2.5) [1.88 ± 0.42] × 1.5–2 [1.92 ± 0.24] μm. Basidia not observed. Cystidia not observed. Tramal hyphae composed of 2–8 μm wide interwoven filamentous hyphae, frequently branching, not or slightly gelatinized. Clamps absent in all parts of basidioma.

Habitat: —Growing in small groups on soil in temperate forests dominated by trees of Larix and Picea . Currently known from northwestern China (Gansu Province, and probably also Xinjiang Uygur Autonomous Region according to the ITS sequence of “Uncultured fungus” ( Fig. 1 ) in Du et al. 2019).

Figures

FIGURE 1. Phylogenetic tree of Gautieria based on ITS sequences. Ramaria botrytis (AMB18201) was selected as outgroup. Nodes were annotated if supported by ≥50% MLB (left) or ≥0.90 BPP (right). The new species was highlighted in bold. The branch shortened to fit the page was indicated by two diagonal lines with the number of times it was shortened. The clades concerned were highlighted with background color and labeled with numbers.

FIGURE 2. Gautieria mianjin (holotype and isotype). a Fresh basidiomata, yellow arrow shows the base, photo by Xiao Liu; b Basidiospores in different angles under scanning electron microscope; c Cells of hymenium. Bars: a=1 cm, b–c=10 μm