Deconica flavum Y. Y. Shen & Y. B. Song

Shen, Yu-Yu, Zhang, Zi-Wen, Li, Wen-Qian, Liu, Xing-Ning, Tian, Fei-Ying, Pang, Chun-Mei, Dai, Wen-Hong, Song, Yao-Bin & Dong, Ming, 2024, Morpho-molecular analysis of two new species Deconica and Entocybe in Agaricales from Mount Tianmu, China, MycoKeys 109, pp. 319-336 : 319-336

Deconica flavum Y. Y. Shen & Y. B. Song sp. nov.

Figs 3 , 4

Etymology.

The specific epithet flavum (Lat.) refers to the species having stramineous color in the center of the pileus.

Holotype.

• China, Zhejiang Province, Hangzhou, National Nature Reserve of Mount Tianmu at 1162 m a. s. l., 30 ° 21 ' N, 119 ° 26.4 ' E ( DDM), grew on litter under coniferous and broad-leaved mixed forest, 2 July 2022, 2381 (holotype), GenBank accessions: OR 906279 ( ITS), OR 906277 ( LSU).

Description.

Pileus convex-campanulate, commonly papillate, light brown (6 D 8) or sunburn (6 D 5), center stramineus (5 C 8), (8 –) 10–20 mm; margin striate, invariable color when bruised, surface flocculose or with white fibrillose patches of veil on half of the pileus. Context fleshy on disk, pale yellowish (6 A 3). Lamellae adnexed to adnate, with decurrent tooth, distant, pompeian yellow (5 C 6), brown shellow (5 C 8), or gold brown (5 D 7). Stipe central, cylindrical, equal to broader at apex, hollow, cartilaginous, flocculose, 11–14 × 1.2–2.7 mm; dark blonde (5 D 4) to light brown (6 D 5), with yellowish white fibrils. Smell indistinct.

Basidiospores fusiform, ellipsoid to ovoid, yellowish brown under light microscopy with germ pore, the middle part concave under scanning electron microscopy, (3.0) 3.3–4.7 (5.1) × (2.2) 2.6–3.3 (4.3) µm, Q = 0.8–1.8, Q av = 1.4 (concave side), (3.6) 4.2–4.9 (5.1) × (2.9) 3.1–3.9 (4.0) µm, Q = 1.0–1.5, Q av = 1.3 (convex side) in frontal view. Basidia cylindrical or claviform with median constriction, 4 - spored, hyaline, thin-walled, 11.7–17.1 × 3.8–5.7 µm. Pleurocystidia type chrysocystidia clavate to broadly clavate, apex mucronate or rostrate, thin-walled, hyaline, with hyaline content, 15.2–26.8 × 5.6–13.0 µm. Pleurocystidia type leptocystidium narrowly utriform, hyaline, thin-walled, abundant, 7.7–17.9 × 3.3–5.7 µm. Cheilocystidia widely utriform, cylindrical, hyaline, 12.3–20.5 × 3.6–5.2 µm. Pileipellis a gelatinous cutis 2.0–4.5 µm diam, hyaline, and thin-walled, with clamp connections. Stipitipellis a cutis 4.7–10.6 µm diam, hyaline, thin-walled, with clamp connections.

Habitat and distribution.

Scattered on litter under coniferous and broad-leaved mixed forests at 1162 m a. s. l., currently only known from Zhejiang Province, China.

Additional material examined

(paratype). • China, Zhejiang Province, Hangzhou, National Nature Reserve of Mount Tianmu at 1162 m a. s. l., 30 ° 21 ' N, 119 ° 26.4 ' E ( DDM), grew on litter under coniferous and broad-leaved mixed forest, 2 July 2022, 2382, GenBank accessions: OR 9066280 ( ITS), OR 906278 ( LSU) .

Figures

Figure 3. Deconica flavum (holotype) a – c basidiomata d – e basidiospores f basidium g pleurocystidia type chrysocystidia h pleurocystidia type leptocystidium i cheilocystidia. Scale bars: 10 mm (a – c); 10 µm (d, g, h); 5 µm (e, f, i).

Figure 4. Micromorphological features of Deconica flavum (holotype) a basidiospores b basidia c pleurocystidia type leptocystidium d cheilocystidia e pleurocystidia type chrysocystidia. Scale bars: 10 µm.