Zhuliangomyces bambusus T. Huang & L.P. Tang, 2022

Huang, Ting, Zhang, Wen-Hao, Huang, Hong-Yan, Gu, Yan-Ming & Tang, Li-Ping, 2022, Two new species of Zhuliangomyces (Amanitaceae) from Hainan Island, China, Phytotaxa 575 (1), pp. 57-67 : 60-62

Zhuliangomyces bambusus T. Huang & L.P. Tang , sp. nov. ( Figs. 2 , 4 & 6a–b ).

MycoBank:—MB 839033.

Diagnosis:— Zhuliangomyces bambusus is similar to Z. ochraceoluteus , differs from the latter in its light brown pileus, with grayish tone at age, predominantly subglobose basidiospores (3.5–4.5 × 3–4.5 μm, Q m = 1.06), and habitat in bamboo duff.

Holotype:— CHINA. HAINAN PROVINCE, Wuzhishan City , fruiting in a small group in the rich litter of Pseudosasa cantorii leaves, 18°51′56”N, 109°40′54”E, elev. 640 m, 12 th August 2020, L. P. Tang 3205 ( MHKMU L. P. Tang 3205 ！).

Etymology:—“ bambusus ” indicates that the species fruits in duff of Pseudosasa cantorii , a kind of bamboo growing in tropical parts of China.

Gene sequences ex-holotype:— MW732473 (ITS) and MW732414 (LSU).

Description:— Basidiomata small-sized. Pileus 35–40 mm diam., hemispherical at first, soon becoming convex, then plano-convex or plane, uplifted when mature, margin striate; surface smooth, strongly viscid, light brown to grayish-brown (5B2–5B4), more or less with grayish tone at age, often slightly darker at center; context quite thin, white (1A1), unchanging; whole pileus easily falling off or separated from stipe collecting. Lamellae free, somewhat distant, up to 3 mm in width, white to cream (2A1), L = 80–90, l = 1–2. Stipe 30–45 × 2–4 mm, central, cylindrical, slightly attenuate upwards, glabrous, viscid, light brown or pale brown (5B2–5B4); stipe base slightly enlarged; basal mycelium white, often with several rhizomorphs; context white (1A1), unchanging, soft to partially hollow in center. Annulus apical, light brown (5B2–5B4), strongly viscid, usually attached to pileus margin. Odor indistinct. Taste not recorded.

Basidiospores [80/4/2] (3) 3.5–4.5 (5) × 3.0–4.5 μm, Q = 1.03–1.07, Q m = 1.06 ± 0.01 (under SEM), mostly subglobose, occasionally globose, inamyloid, hyaline, thin-walled, smooth under the light microscope, but verruculose under SEM; apiculus relatively short. Basidia 21–26 × 5–7 μm, clavate, 4-spored; sterigmata 3–5 μm long. Cystidia absent. Lamella trama bilateral. Mediostratum 20–45 μm wide, composed of abundant, ellipsoid to clavate inflated cells 37–85 × 7–11 μm; filamentous hyphae 3–11 μm diam., abundant; vascular hyphae rare. Lateral stratum composed of abundant, ellipsoid to clavate inflated cells 20–75 × 6–12 μm; filamentous hyphae 3–10 μm diam. Subhymenium 20–60 μm thick, with 2–4 layers of subglobose, ovoid to ellipsoid or irregular cells 7–30 × 6–18 μm. Pileipellis 80–110 μm thick, an ixotrichoderm composed of vertically arranged, septate, filamentous hyphae with terminal cells cylindrical to narrowly clavate 35–70 × 2–5 μm. Stipe trama composed of longitudinally arranged, ellipsoid to long clavate terminal cells 52–205 × 12–35 μm, thick-walled; filamentous hyphae 4–10 μm diam., slightly thick-walled, abundant; vascular hyphae rare. Clamp connections abundant, present in all parts of basidiomata.

Habitat :— Gregarious in small groups in duff of decaying bamboo leaves or branches; fruiting in August.

Distribution:— Hainan Province, China.

Additional specimen examined:— CHINA. HAINAN PROVINCE, Wuzhishan City, in small groups growing in bamboo duff of Pseudosasa cantorii , 18°51′56″N, 109°40′55″E, elev. 650 m, 12 th August 2020, H. Y. Huang 757 ( MHKMU H. Y. Huang 757) .

Figures

FIGURE 2. Basidiomata of Zhuliangomyces bambusus. a, b from MHKMU H.Y. Huang 757, photos by H.Y. Huang; c, d from MHKMU L.P. Tang 3205 (holotype), photos by L.P. Tang. Bars: 1 cm.

FIGURE 4. Microscopic features of Zhuliangomyces bambusus (MHKMU L.P. Tang 3205, holotype). a. Basidia; b. Basidiospores; c. Pileipellis; d. Stipe trama. Bars: a = 6 μm, b = 2 μm, c = 10 μm, d = 20 μm.

FIGURE 6. Basidiospores of two new species Zhuliangomyces under SEM. a–b Z. bambusus (MHKMU L.P. Tang 3205, holotype); c–d Z. terrus (MHKMU M. Mu 647, holotype). Bars: a, c= 5 μm, b, d = 1 μm.