Favolaschia variistipitata W.H. Lu, Tibpromma & Karun., 2025

Lu, Wenhua, Chen, Xuemei, Kumla, Jaturong, Suwannarach, Nakarin, Elgorban, Abdallah M., Dai, Dong-Qin, Tibpromma, Saowaluck & Karunarathna, Samantha C., 2025, A new species of Favolaschia (Agaricales, Mycenaceae) from Yunnan Province, China, Phytotaxa 694 (2), pp. 144-160 : 148-150

Favolaschia variistipitata W.H. Lu, Tibpromma & Karun. , sp. nov. ( Figs 1–3 )

MycoBank number: MB 856190

Diagnosis: Favolaschia variistipitata differs from the phylogenetically closely related F. tonkinensis by its smaller basidiomata (3–11 mm vs. 6–24 mm), and smaller basidiospores (5.0–8.7 × 3.5–6.5 µm vs. 8–12.5 × 7–10.5 µm, Singer 1974), and the absent of bioluminescence.

Etymology: The species epithet “ variistipitata ” refers to the species with or without stipe.

Holotype: GMB1061

Basidiomata annually, gregarious, gelatinous. Pileus 3.5–11 × 2.5–7 mm, glabrous, flabelliform, reniform, semicircular to subcircular, sometimes circular; surface snow white (1A1) to greyish white (1B1) or pale yellow (4A4) when fresh, dark grey or brownish grey (6E2) upon drying, convex, reticulate pattern, pruinose in young, becomes glabrous in age; margin straight or incurved, crenulate; context thick. Hymenophore consisting of up to 120 pores per basidiomata; pore edges pale white (fresh and dry), 10 µm wide, thin, glabrous; Pores 0.1–0.5 mm in diam., irregular or radially elongated, polygonal, increase in size near the base and become smaller toward the edge. Stipe mostly present, 1.5–3 × 0.5–1 mm when young, sometimes 9 × 3 mm in age, concolourous with pileus surface, slightly pulverulent, laterally attached to the pileus, subcylindrical with a slightly swollen base.

Basidiospores (3.7–)5.0–8.7(–9.3) × (2.8–)3.5–6.5(–7.2) µm, L = 6.68 μm, W = 4.69 μm, Q = 1.3–1.6, Qm = 1.43, subglobose to broadly ellipsoid, hyaline, thin-walled, smooth, guttules, amyloid. Basidia 21–29 × 7–9.5 μm, clavate to cylindrical, 2-spored, sterigmata up to 5 μm long, apex broadly rounded; basidioles 17–31 × 6–9 µm, similar in shape to the basidia. Cheilocystidia 19–36 × 4.7–8.7 μm, cylindrical or clavate, obtuse, thin-walled. Gloeocystidia 17–68 × 14–31.8 μm, cylindrical, ellipsoid to subglobose with dense brown or dark brown contents. Acanthocystidia absent. Pileipellis hyphae subparallel, smooth to diverticulate, thin-walled, 2–5 μm in diam. Tramal hyphae subparallel with dense contents and some collapsed, thin-walled, 2–4 μm in diam. Hyphae in stripe cytoplasmic content, interwoven, branching, 2–3 μm broad. Clamp connections present in all tissue types. Bioluminescence absent.

Material examined: CHINA • Yunnan Province, Dehong Dai and Jingpo Autonomous Prefecture, Fengping Town ; 24°42′01″N, 98°49′18″E; elev. 830 m; 24Apr. 2024; X. Chen, Eva 1121 ; on a dead bamboo; holotype: GMB1061 ( GMB!) .

Distribution and ecology: Favolaschia variistipitata grows on dead bamboo and is distributed in subtropical areas of Yunnan Province, China.

Notes: Favolaschia variistipitata within the Favolaschia sect. Anechinus was collceted from subtropical area of Yunnan Province, China.Phylogenetically, two samples of F.variistipitata (GMB1061 and GMB1062)formed a distinct linage with high support (99% BS/1 PP, Figure 1 ) that is sister to F. tonkinensis and closely related to F. tenuissima Q.Y. Zhang & Y.C. Dai (797: 2023). However, F. tonkinensis can be easily distinguished from F. variistipitata by its bigger basidiomata (6–24 mm vs. 3–11 mm), and bigger basidiospores (8–12.5 × 7–10.5 µm vs. 5.0–8.7 × 3.5–6.5 µm, Singer 1974), shorter stipe (1–3 × 0.5–1 mm vs. 9 × 3 mm), and the former has the bioluminescence characteristics. While F. tenuissima differs from F. variistipitata in having smaller basidiomata (3–5 × 1–3 mm vs. 3.5–11 × 2.5–7 mm), few pores (10–20 vs. 120), smaller cheilocystidia (15–23 µm× 3–6 µm vs. 19–36 × 4.7–8.7 μm), and the absence of gloeocystidia.

Other material examined: CHINA • Yunnan Province, Dehong Dai and Jingpo Autonomous Prefecture, Fengping Town ; 24°42′01″N, 98°49′18″E; elev. 830 m; 24 Apr. 2024; X. Chen, Eva 0319 ; on a dead bamboo; isotype: GMB1062 ( GMB!) .

Figures

FIGURE 1. Phylogenetic tree generated from ML analysis based on a combination of ITS + LSU sequence datasets. BS values of ML equal to or more than 75% and PP values of BI equal to or more than 0.90 are given above the branch as BS/PP. The new taxon is in red. “T” means the sequences are from the type specimen.

FIGURE 2. Basidiomata of Favolaschia variistipitata. a–c. GMB1061, holotype. d–e GMB1062, isotype. Scale bars: 10 mm.

FIGURE 3. Microscopic structures of Favolaschia variistipitata (GMB1061, holotype). a. Basidiospores. b. Basidia and basidioles. c. Cheilocystidia. d. Gloeocystidia. e. Hyphae from the stipe.