Laccaria pumila Fayod
Year: 2026
Type: article
Abstract: Laccaria pumila Fayod, Annali R. Accad. Agric. Torion 35: 91 (1893) Figs 6, 7, 10 g – i Chinese name. 矮蜡蘑 (Ai La Mo). Description. Basidiomata medium-sized. Pileus 10–56 mm in diameter, initially hemispherical to convex, becoming applanate with age, often plano-concave at maturity, occasionally with an uplifted margin; surface glabrous to finely fibrillose, becoming more distinctly fibrillose with age, distinctly striate to translucent-striate when fresh; hygrophanous, orange-brown (# a 6532 a) when fresh, fading rapidly to pale brown (# f 2 b 790) and finally buff (# f 0 dcb 4); margin crenate, orange-brown (# a 6532 a); context thin, 1–2 mm thick. Lamellae distant, segmentiform to subventricose, adnexed to subdecurrent, waxy, pinkish-flesh-colored (# d 28 c 8 c), 1–3 mm high; edge even or entire; lamellulae in 2–3 tiers. Stipe 20–76 × 3–6 mm, cylindrical, central, either nearly equal or slightly enlarged and subclavate toward the base, occasionally caespitose; surface dry, subglabrous to finely fibrillose, often faintly longitudinally striate, concolorous with the pileus; basal mycelium white; context broadly fistulose, orange-brown (# a 6532 a). Odor and taste not observed. Basidia 44–68 × 11–17 µm, av. 53.5 ± 5.9 × 14.1 ± 1.5 μm, clavate, 2 – spored, sterigmata 6–14 µm × 3–5 µm, av. 10.1 ± 1.7 × 3.9 ± 1.5 μm. Basidiospores (excluding ornamentation) [100 / 2 / 2] (9.5 –) 10–13 (– 14.1) × (8.9 –) 9–12 (– 13.5) µm, av. 11.4 ± 0.79 × 10.6 ± 0.98 μm, Q m = 1.02–1.13, Q av. = 1.07 ± 0.30, subglobose to broadly ellipsoid, occasionally globose or ellipsoid, hyaline, echinulate, spines 1–2 µm long, 0.8–1.2 µm wide at the base, crowded. Cheilocystidia 18–39 × 4–8 µm, av. 29.5 ± 5.3 × 5.9 ± 0.9 μm, narrowly clavate, flexuose or mucronate, rarely branched, thin-walled, colorless, and hyaline, abundant. Pleurocystidia 15–33 × 3–7 µm, av. 23.6 ± 4.2 × 5.2 ± 1.1 µm, narrowly clavate to subclavate, flexuose or mucronate, rarely branched, thin-walled, hyaline. Lamellar trama 120–155 µm thick, regular, composed of slightly thick-walled, filamentous hyphae 3–8 µm wide; the lamellar edge is primarily composed of sterile basidia. Subhymenium 15–30 μm thick, tightly interwoven, fusiform or irregular cells, 3–8 × 3–7 μm. Pileipellis 100–130 µm thick, light orange hyaline in 5 % KOH, composed of appressed, parallel, simply septate, thin-walled, cylindrical, filamentous hyphae 6–10 µm wide, colorless, and hyaline. Stipitipellis is composed of appressed, parallel, simply septate, thick-walled, hyphae 3–6 µm wide; stipe trama is composed of longitudinally arranged, pastel red in 5 % KOH, clavate terminal cells, infrequently branching, septate, thick-walled, hyaline 3–9 µm wide. Caulocystidia absent. Clamp connection present at some septa in pileipellis, lamellae, and stipitipellis. Habitat and phenology. Scattered, gregarious, or caespitose on the edges of ditches, in grasslands, on sandy soils, and beside woods. Additional specimens examined. China • Xizang Autonomous Region, Linzhi City, 30°15'59.32"N, 96°38'54.57"E, ele. 3,700 m., 25 July 2024, S. M. Tang, 2024072521 (HKAS 147008); • ibid., 25 July 2024, S. M. Tang, 2024072522 (HKAS 147009). Notes. Following BLAST searches of NCBI GenBank, the closest matches to the ITS and LSU sequences of the collection (HKAS 147008) are L. pumila (specimen GMM 7637, ITS 99.65 % sequence identity; specimen AWW 446, LSU 99.88 % sequence identity). The morphology of the Xizang collections matches the description of L. pumila, originally described from France (Fayod 1893). However, unlike those described in previous studies, both the basidiomata (pileus 15–56 mm in diameter, stipe 20–76 × 3–6 mm) and basidia (44–68 × 11–17 μm) are larger, and pleurocystidia were also observed. Phylogenetically, the specimens clustered with L. pumila in the same clade. Therefore, based on both morphological and phylogenetic analyses, the two specimens are identified as L. pumila.
Institution: Dali University
Language: English
Domain: Life Sciences
Open Access status: green
OpenAlex ID: W7204455064