Zhuliangomyces terrus 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 : 62-64

Zhuliangomyces terrus T. Huang & L.P. Tang , sp. nov. ( Figs. 3 , 5 & 6c–d ).

MycoBank:—MB 839039.

Diagnosis:— Zhuliangomyces terrus is similar to Z. ochraceoluteus but differing in its chocolate or dark brown pileus when young, non-striate margin, mostly broadly ellipsoid basidiospores (4–5 × 3–4.5 μm, Q m = 1.24), and fruiting in soil.

Holotype:— CHINA. HAINAN PROVINCE: Ledong Li Autonomous County, Jianfengling National Forest Park, solitary or scattered on soil in a tropical broad-leaved forest, 18°44’16”N, 108°50’11”E, elev. 810 m, 10 th August 2020, M. Mu 647 ( MHKMU M. Mu 647 ！).

Etymology:—“ terrus ” refers to the fact that the species fruits on soil.

Gene sequences ex-holotype:— MW732472 (ITS) and MW732413 (LSU).

Description:— Basidiomata small-sized. Pileus 40 mm diam., hemispherical at first, soon becoming convex, then plano-convex or plane, often with a relatively low, broad umbo, chocolate or deep coffee or dark brown (5F7–5F8), particularly obvious when young, pale toward margin, pale brown to brown (5B5–5B6); surface smooth, strongly viscid; margin non-striate; context thin, white (1A1), unchanging. Lamellae free, up to 2 mm in width, white to cream (1A1), close to crowded, L = 150–160, l = 1–2. Stipe 60–65 × 4–5 mm, central, cylindrical, slightly attenuate upwards, light brown to brown (5B5–5B6), glabrous, viscid; context white, unchanging, soft to partially hollow in the center; stipe base subcylindrical. Annulus apical, brown (5B5–5B6), strongly viscid. Odor indistinct. Taste not recorded.

Basidiospores [80/4/2] (3) 4.0–5.0 × 3.0–4.5 (5) μm, Q = 1.15–1.28, Q m = 1.24 ± 0.03 (under SEM), predominantly broadly ellipsoid, inamyloid, colorless, hyaline, thin-walled, smooth under the light microscope, but verruculose under SEM. Basidia 22–30 × 5–8 μm, clavate, 4-spored; sterigmata 3–5 μm long. Cystidia absent. Lamella trama bilateral. Mediostratum 20–50 μm wide, composed of abundant, ellipsoid to clavate inflated cells 30–100 × 10–19 μm; filamentous hyphae 2–9 μm diam., abundant; vascular hyphae rare. Lateral stratum composed of abundant, ellipsoid to clavate inflated cells 35–80 × 11–20 μm; filamentous hyphae 5–13 μm diam. Subhymenium 25–50 μm thick, with 2–3 layers of subglobose, ovoid to ellipsoid or irregular cells 10–20 × 5–15 μm. Pileipellis 100–140 μm thick, an ixotrichoderm composed of vertically arranged terminal cells, 35–70 × 2–5 μm, cylindrical to narrowly clavate. Stipe trama composed of longitudinally arranged terminal cells 72–170 × 16–54 μm, slightly thick-walled, ellipsoid to very narrowly clavate; filamentous hyphae 4–13 μm diam., slightly thick-walled; vascular hyphae rare. Clamp connections abundant, present in all parts of basidiomata.

Habitat :— Solitary or scattered on ground in a tropical broad-leaved forest; fruiting in August.

Distribution:— Hainan Province, China.

Additional specimen examined:— CHINA. HAINAN PROVINCE, Ledong Li Autonomous County, Jianfengling National Forest Park , solitary or scattered on soil in a tropical broad-leaved forest, 18°44′33″N, 108°50′32″E, elev. 1000 m, 10 th August 2020, T. Huang 345 ( MHKMU T. Huang 345) .

Figures

FIGURE 3. Basidiomata of Zhuliangomyces terrus. a, b from MHKMU M. Mu 647 (holotype), photos by M. Mu; c–e from MHKMU T. Huang 345, photos by T. Huang. Bars: 1 cm.

FIGURE 5. Microscopic features of Zhuliangomyces terrus (MHKMU M. Mu 647, holotype). a. Basidia; b. Basidiospores; c. Pileipellis; d. Stipe trama. Bars: a = 6 μm, b = 2 μm, c = 15 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.