Laccaria violaceonana G. Zhao, S. M. Tang & Z. L. Luo 2026, sp. nov.
Year: 2026
Type: article
Abstract: Laccaria violaceonana G. Zhao, S. M. Tang & Z. L. Luo sp. nov. Figs 4, 5, 10 a – c Chinese name. 小紫蜡蘑 (Xiao Zi La Mo). Diagnosis. Laccaria violaceonana is characterized by medium-sized basidiomata, a convex pileus, a stipe with an enlarged base, deep purple, globose to subglobose basidiospores, and basidia that are mostly 4 - spored. Etymology. The epithet “ violaceonana ” refers to the purple-violet coloration of its basidiomata and their smaller stature compared with L. amethystina Cooke. Holotype. China • Yunnan Province, Puer City, Ailao Mountain, 24°30'54.40"N, 100°16'42.08"E, ele. 2,300 m., 11 August 2020, S. M. Tang, 2020081105 (HKAS 123243). Description. Basidiomata medium size. Pileus 10–36 mm in diam., convex, becoming applanate to plano-concave, deep purple (# 800080), smooth and translucent striate on the surface, a slightly depressed to depressed shape of center, becoming reflexed on the margin with age, margin undate, hygrophanous, and context thin, 0.6–1.5 mm. Lamellae distant, broad, segmentiform, subdecurrent, purple (# 9400 d 3), concolorous to pileus, 1–2 mm in height, lamella edge even or entire; lamellulae in 1–2 tiers. Stipe 13–22 × 2–4 mm, cylindrical, central or eccentric, equal with an enlarged base, deep purple (# 800080), concolorous with pileus, becoming dark brown (# 8 b 4513) after loss of moisture or with age, smooth, basal mycelium white; stipe context broadly fistulose, deep purple (# 800080). Taste and smell not observed. Basidia 29–47 × 10–16 µm, av. 39.7 ± 5.4 × 13.4 ± 1.6 μm, clavate, mostly 4 - spored, rarely 2 - spored, sterigmata 3–12 × 2–6 µm, av. 8.1 ± 1.7 × 2.9 ± 1.1 μm. Basidiospores (excluding ornamentation) [150 / 3 / 3] (5.5 –) 6.0–9.6 (– 9.9) × (5.1 –) 5.4–9.0 (– 9.5) µm, av. 7.5 ± 0.8 × 7.3 ± 0.8 μm, Q m = 1.0–1.12, Q av. = 1.03 ± 0.02, globose to subglobose, hyaline, echinulate, spines 1–4 µm long, 0.8–1.4 µm wide at the base, crowded. Cheilocystidia 26–76 × 4–13 µm, av. 48.9 ± 13.6 × 8.4 ± 2.3 μm, narrowly utriform, flexuose or mucronate, branches, thin-walled, colorless, and hyaline. Pleurocystidia 15–42 × 3–9 µm, av. 24.7 ± 7.5 × 5.5 ± 1.6 µm, narrowly clavate to subclavate, flexuose or mucronate, rarely branched, thin-walled, hyaline, abundant. Lamellar trama 113–120 µm thick, regular, composed of slightly thick-walled, filamentous hyphae 2–6 µm wide; lamellar edge more in several sterile basidia. Subhymenium 10–18 μm thick, tightly interwoven, fusiform or irregular cells, 8–11 × 2–7 μm. Pileipellis 25–50 µm thick, grayish, inflated hyaline in 5 % KOH, composed of appressed, parallel, simply septate, thin-walled, cylindrical, filamentous hyphae 10–17 µm wide, colorless, and hyaline. Stipitipellis composed of appressed, parallel, simply septate, thick-walled, hyphae 4–8 µm wide; stipe trama is composed of longitudinally arranged, grayish in 5 % KOH, clavate terminal cells, infrequently branching, septate, thick-walled, hyphae hyaline 3–10 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, on sandy soils, and beside woods. Additional specimens examined (Paratype). China • Yunnan Province, Puer City, Ailao Mountain, 24°30'54.40"N, 100°16'42.08"E, ele. 2,300 m., 3 August 2020, S. M. Tang, 2020080301 (HKAS 123290); • ibid., 3 August 2020, S. M. Tang, 2020080303 (HKAS 123240). Notes. In the multilocus phylogenetic analysis, Laccaria violaceonana is sister to L. fulvogrisea Popa, Rexer & G. Kost. However, L. fulvogrisea can be distinguished by its gray to brownish pileus and lamellae, larger stipe (30–70 × 3–5 mm) that is slightly darker gray than the pileus, larger basidia (40–50 × 10–15 µm), clavate and flexuous pleurocystidia, cheilocystidia (30–50 × 3–7 µm) ranging from clavate to subcapitate, and the absence of caulocystidia on the stipe surface (Popa et al. 2014). The ITS sequence divergence between L. violaceonana (HKAS 123243) and L. fulvogrisea (KUN F 78556) is 2.03 % (12 / 591, excluding gaps). Macroscopically, Laccaria violaceonana shares purple basidiomata with L. amethystina, L. amethysteo-occidentalis G. M. Muell, L. dallingii Corrales, Ovrebo, A. W. Wilson & G. M. Muell, L. japonica Popa & K. Nara, L. moshuijun, and L. violaceotincta K. P. D. Latha, K. N. A. Raj & Manim but can be distinguished by a combination of micromorphological characteristics. Compared with L. amethystina and L. amethysteo-occidentalis, L. violaceonana possesses abundant pleurocystidia, which are absent in the latter two species. Additionally, its basidiospores (6.0–9.6 × 5.4–9.0 µm) are smaller than those of L. amethystina (7.5–9.5 × 7.5–9.5 µm), its basidia (29–47 × 10–16 µm) are smaller than those of L. amethysteo-occidentalis (34–56.5 × 9.7–14.7 µm), and its narrowly utriform cheilocystidia (26–76 × 4–13 µm) differ in shape from those of both species (Cooke 1884; Mueller 1984). In contrast to L. dallingii, L. violaceonana has pleurocystidia and narrowly utriform rather than simple cylindrical cheilocystidia and lacks the distinctive orange-pink KOH reaction of the hyphae observed in the latter (Corrales et al. 2020). It is distinguished from L. japonica and L. moshuijun primarily by its hyphal structure: L. violaceonana has appressed, parallel hyphae in both the pileipellis and stipitipellis, in contrast to the interwoven, radiating hyphae with intracellular pigmentation found in the latter two species. Furthermore, the spore spines of L. violaceonana (1–4 µm long) are longer than those of L. japonica (0.8–1 µm), and its cheilocystidia are narrowly utriform, differing from the cylindrical to clavate or apically branched or capitate forms found in L. japonica and L. moshuijun (Popa et al. 2017 a, 2017 b). The most notable distinction from L. violaceotincta is the presence of pleurocystidia in L. violaceonana, along with a broader spore size range (6.0–9.6 × 5.4–9.0 µm vs. 7–8 × 7–8 µm) (Latha et al. 2019).
Institution: Dali University
Language: English
Domain: Life Sciences
Open Access status: green
OpenAlex ID: W7204479871