Calocybe violacea T. Bau & L.S. Mu, 2023

Mu, Lisong & Bau, Tolgor, 2023, A new species of Calocybe (Agaricales, Basidiomycota) from China, Phytotaxa 600 (2), pp. 73-83 : 79

Calocybe violacea T. Bau & L.S. Mu , sp. nov. ( Figure 3a–b , Figure 4a–d ).

MycoBank: 846890

Diagnosis:—Differs from related species by its convex to applanate, purple to bluish-purple pileus, white lamellae, purple-black, bluish-purple to white stipe, and relatively larger basidiospores, pileipellis a cutis, hyphae light purple-brown, stipitipellis composed of hyphae light brown, light purple-brown and light purple.

Etymology:—Refers to the blue-purple color on the cap and stipe of basidiomata.

Holotype:— CHINA. Yunnan Province: Chuxiong Yi Autonomous Prefecture, Chuxiong, Lucheng Town, Haizi Dam, in a forest dominated by Quercus spp. , elevation 1836 m, 101°57’E, 24°97’N, 30 November 2021, leg. Jianneng Zhao ( HMJAU65324 ).

Description:— Basidiomata small-sized. Pileus 2.5–3.5 cm diam., hemispherical, margin involute when young, becoming convex to applanate at maturity, surface dry, purple-black (18D5) to dark purple (17E8) at center, becoming purple (17C6) to bluish-purple (19A4) towards the margin; context white (19A1). Lamellae sinuate to adnate, crowded, L=50–60, I=1–3, white (19A1), edge entire. Stipe 4.5–7.5 × 0.5–1 cm, central, cylindrical, purple-black (18E5), purple (18C6), bluish-purple (19B6), blue (21A7) to white (19A1), with white pubescence at the base, fibrous. Odor faint. Spore deposit white.

Basidiospores (5.7) 6.4–6.7 (7.6) × (2.6) 3.0–3.2 (3.4) μm, 6.5×3.1 µm on average, Q=1.86–2.46, Q m =2.12 ± 0.12, oblong, colorless, hyaline, smooth, thin-walled, with oil droplets, cyanophilous, inamyloid. Basidia 15–24 × 5–7 μm, clavate, with oil droplet, with 4 (2) sterigmata, hyaline, smooth, thin-walled, with siderophilous granules. Hymenophoral trama regular, thin-walled, colorless, smooth, 4–11 μm wide. Cystidia absent. Pileipellis a cutis, hyphae 3–9 μm wide, light purple-brown after. Stipitipellis composed of thin-walled, 2–4 µm wide hyphae often light brown, light purple-brown, and light purple. Clamp connections present.

Habit, habitat, and distribution: Gregarious, on soil in broad-leaved forests dominated by Quercus spp.

Additional specimen examined: Chuxiong Yi Autonomous Prefecture, Chuxiong, Lucheng Town, Haizi Dam, in a forest dominated by Quercus spp. , elevation 1836 m, 101°57’E, 24°97’N, 26 November 2021, Jianneng Zhao ( HMJAU65325 , paratype!) .

Figures

FIGURE 3. Calocybe violacea, a. Holotype!, HMJAU65324; b. Paratype!, HMJAU65325; Scale bars: a–b=1cm. Pictures by J. N. Zhao.

FIGURE 4. Calocybe violacea (HMJAU65324 holotype!). a. Basidiomata; b. Basidiospores; c. Basidia; d. Pileipellis. Scales bar a=1 cm, b and c =5 μm, d=10 μm. Drawings by L.S. Mu.