Cyathus magnipilosus J.S. Góis, R. Cruz & K. Hosaka, 2024

Góis, Jefferson Dos Santos, Cruz, Rhudson Henrique Santos Ferreira Da, Baseia, Iuri Goulart & Hosaka, Kentaro, 2024, A new species of Cyathus (Nidulariaceae, Basidiomycota) from Kalimantan, Borneo, Phytotaxa 677 (1), pp. 66-76 : 70-71

Cyathus magnipilosus J.S. Góis, R. Cruz & K. Hosaka , sp. nov. Fig. 3

MycoBank no.: MB854867

Diagnosis:— Cyathus magnipilosus is characterized by an exoperidium with lighter colors, a slightly fimbriated mouth in a continuous pattern, a long exoperidium tomentum (up to 1.5 mm), black peridioles with a smooth surface, elongated to cylindrical basidiospores, and single-layered cortex.

Etymology:—refers to the long and well-defined tufts of tomentum.

Holotype:— INDONESIA. West Kalimantan, Borneo: Betung-Kerihun National Park , 1°24’18.3” N, 112°28’30.9” E, elev. 187 m, H. Tsukaya. 22 December 2011. (TNS-F-45956!).

Gene sequence holotypes:—ITS (PQ045665), LSU (PQ046248).

Description:— Basidiomata infundibuliform, 8.6–9.6 mm in height, 5.8–6.5 mm at the mouth, not expanded in the top or tapering at the base. Pedicel absent. Emplacement 1.9–3.1 mm diam., light brown (5D8), conspicuous, smooth. Exoperidium hirsute, golden brown to linoleum brown (5D7–5E7), with long tomentum of 1.0– 1.5 mm, arranged in irregular and flexible tufts. External wall smooth to inconspicuously plicate, with 0.5–0.7 mm between the folds. Mouth slightly fimbriate in a continuous pattern, 0.2–0.3 mm, light brown (5D8). Mesoperidium dark brown in color. Endoperidium brownish grey to brownish orange (6C2–6C3), inconspicuously plicate with 0.4–0.7 mm between the folds, perceptibly bright, not contrasting with the exterior. Basal triangle 1.8–3.6 mm, black in color. Epiphragm not observed; peridium walls microscopically composed of three different layers: (1) outer wall composed of aseptate interwoven hyphae with 2.9–3.2 µm wide with clamp connections, unchanged in KOH; (2) middle layer composed of pseudoparenchymatous, with cells 15.3–22.0 × 11.2–18.7 µm, globose to elongated (Q = 1.0–1.9); (3) inner wall composed of densely interwoven hyphae with 2.4–3.3 µm wide with clamp connections, unchanged in KOH.

Peridioles black in color, 1.9–2.1 × 1.7–1.9 mm, up to 6 per basidiomata, circular to elliptical at the edges; peridiole surface smooth in the upper part; tunica present, thin, hyaline. Single-layered cortex with compact hyphae, slightly wavy at the bottom. Hymenium grey in color, 1.4 mm in width × 0.08 mm in height; sub-hymenium grey in color, 0.10 mm thick in the upper part, 0.04 mm in the lateral part, and 0.10 mm at the base, microscopically composed of interwoven hyphae in a gelatinous matrix

Basidiospores smooth, hyaline, 7.4–15.6 × 4.1–9.7 µm (L = 10.0 µm; W = 5.4 µm), elongated to cylindrical (Q = 1.6–2.3), elongated shape in average (Qm = 1.9), apicule absent, and basidiospore wall 0.9–2.1 µm.

Habitat and distribution:—On decaying wood, with gregarious growth. The new species is only known from the type locality, a National Park located in Indonesia.

Figures

FIGURE 3. Cyathus magnipilosus (TNS-F-45956). A. Exoperidium hirsute, with long tufts of tomentum; B. Upper view of peridioles with circular to elliptical shape and smooth surface; C. Peridiole with single-layered cortex; D. Basidiospores. Scale bars: A–C = 2 mm, D = 5 µm. Photos by: J. S. Góis.