Cyclocybe suberebia R.L. Zhao & X.Y. Zhu, 2023

Zhu, Xin-Yu, Nyima, Tenzin, Vizzini, Alfredo, He, Mao-Qiang, Phurbu, Dorji & Zhao, Rui- Lin, 2023, Two new species of Cyclocybe (Agaricales, Tubariaceae) from China, Phytotaxa 620 (1), pp. 33-46 : 39-40

Cyclocybe suberebia R.L. Zhao & X.Y. Zhu sp. nov.

Fungal Names No: 571268

FoF number: 13981

Figs 3A, B , 4

Diagnosis. this species is characterized by its dark brown to light brown pileus. It differs from C. erebia in spore of size. It differs from C. erebioides in annulus, C. erebioides with a wide and complex membranous annulus, C. suberebia with a simple membranous annulus, and C. erebioides with clamp-connections, but C. suberebia clampless hyphae.

Etymology: suberebia , from the Latin sub = near, referring to its similarity to C. erebia .

Description. Basidiomes small. Pileus 22–37 mm in diam., broadly convex when young and plane when mature, not distinctly depressed or umbo, hygrophanous, viscid, glabrous, yellowish brown to brown, generally darker in the center and fading toward the margin, margin distinctly striate, not involute. Context thin, up to 1 mm, concolorous with pileus surface. Lamellae adnate or subdecurrent, thick, crowded, with series of 1–3 lamellulae, at first whitish, then light brown, edges with distinctly white. Stipe 41–53 × 2–3 mm, central, cylindrical, hollow, dry, fibrous, with annular zone, at first whitish, darkening with age or at touch to brown. Annulus single, white, membranous, persistent, upturned. Odor not distinctive. Taste indistinct.

Basidiospores 9.4–11.1 × 4.5–5.6 μm, [x = 10.2 ± 0.5 × 5.1 ± 0.3, Q = 1.8–2.4, Q m = 2.0 ± 0.1, n =20], long ellipsoid, oblong, subellipsoid to subamygdaliform, smooth, thick-walled, some with oil-like droplets, no germ pore, brownish to brown. Basidia 22.4–27.4 × 5.8–8.2 μm, clavate, middle constrained, 1-, 2- to 3-spored, most 2-spored and without 4-spored, thin walled, hyaline. Pleurocystidia 49.4–60.5 × 8.0–13.9 μm, generally utriform, sometimes cylindrical, thin-walled, hyaline, numerous. Cheilocystidia 51.2–62.2 × 11.0–15.8 μm, mostly utriform, thin walled, hyaline. Hymenophoral trama subregular, consisting of 2.9–5.9 μm-wide hyphae. Pileipellis hymeniform and formed by vesicular to clavate elements, 21.7–29.1 × 8.7–15.2 μm. Pileocystidia not observed. Caulocysidia not observed. Clamp-connections absent.

Habitat, ecology and distribution. Solitary or scattered on soil, often under conifers, known from Chongqing, China; from July to October.

Material examined. China. Chongqing: Kaizhou Country, Xuebaoshan National Natural Reserve (31°35’17” N, 108°41’18” E), alt. 1350 m, 11 September 2021, collected by Xin-Yu Zhu, Ming-Zhe Zhang, Yang Liu. ZRL20211502 (Holotype: HMAS 286977 ) ; China. Chongqing: Kaizhou Country, Xuebaoshan National Nature Reserve (31°35’17” N, 108°41’18” E), alt. 1350 m, 10 September 2021, collected by Xin-Yu Zhu, Ming-Zhe Zhang, Yang Liu. ZRL20211500 ( HMAS 286975 ) ; China. Chongqing: Kaizhou Country, XueBaoShan National Nature Reserve (31°35’17” N, 108°41’18” E), alt. 1350 m, 11 September 2021, collected by Xin-Yu Zhu, Ming-Zhe Zhang, Yang Liu. ZRL20211501 ( HMAS 286976 ) ; China. Chongqing: Kaizhou Country, XueBaoShan National Nature Reserve (31°35’17” N, 108°41’18” E), alt. 1350 m, 11 September 2021, collected by Xin-Yu Zhu, Ming-Zhe Zhang, Yang Liu. ZRL20211520 ( HMAS 286978 ) .

Figures

FIGURE 3. Basidiomes of the two new Cyclocybe species. A, B Cyclocybe suberebia (HMAS-286977) C, D Cyclocybe dinggyensis (HMAS-286979). Scale bars: 1 cm.

FIGURE 4. Microscopic features of Cyclocybe suberebia (HMAS 286977, holotype) A, Basidiospores; B, Basidia; C, Pleurocystidia; D, Cheilocystidia; E, Pileipellis hymeniphorm.