Amanita fense M. Mu & L.P. Tang, 2021

Mu, Man, Huang, Hong-Yan, Zhang, Wen-Hao & Tang, Li-Ping, 2021, A new species with pink lamellae of Amanita section Caesareae from China, Phytotaxa 478 (1), pp. 141-150 : 145-147

Amanita fense M. Mu & L.P. Tang , sp. nov. ( Figs. 3–4 ).

MycoBank: MB 835965.

Etymology:—“ fense ” means pinkish, pale rose in Chinese, and refers to the color of the lamellae.

Diagnosis:—Belonging to Amanita section Caesareae , characterized by a buff to cacao brown pileus; a narrow subhymenium (2–3 cells thick); pinkish white to light pink lamellae; membranous annulus; ellipsoid to elongate and inamyloid basidiospores (11.5–14.0 × 8.0–10.0 µm with Q = 1.38–1.63 and Q m = 1.52 ± 0.09); abundant clamps.

Holotype:— CHINA. YUNNAN PROVINCE: Yongsheng County, 26°40′23”N, 100°43′19”E, elev. 2655 m, 2nd October 2018, H. Y. Huang 174 (MHKMU-Huang174).

Gene sequences ex-holotype:— MT108790 (ITS); MT138689 (LSU).

Description:— Basidiomata medium-sized, mostly solitary. Pileus 5–8 cm in diam, plano-convex to applanate, shiny,

slightly viscid when moist, surface buff to cacao brown (5C3–5, 5D4–6, 6C6) when young, then golden brown (5D5–

7, 6D6) to bronze brown (5E5– 8, 6E 5–6), dark at the center, covered with pearl white (3B1) or grayish white (29B1,

30B1) cottony-floccose scales, paler towards the margin when old; margin striate 0.3–0.4 R (or 30–40% of the radius);

trama pale white, thin. Lamellae 0.5–0.9 cm broad, free, pinkish white, pale pink or shell pink (8A2–3, 9A2, 10A2), the pink tones becoming more obvious after drying, unchanging when injured, moderately crowded, 70–80 complete lamellae/cap, 1–2 lamellulae between two complete lamellae, lamellulae subtruncate to truncate. Stipe 7–10 cm long × 0.7–1.1 cm diam, surface white (1A1) with faint pink hues, cylindrical, attenuated upwards, hollow in center, context pinkish white or pale pink (9A2, 10A2). Basal bulb absent. Volval remnants on the stipe base saccate 2.0–2.8 × 1.4–1.8 cm diam, soft, white, off-white (1A1) to pinkish white (9A2, 10A2). Annulus persistent, upper-middle, thin, small, membranous, fragile and easily detached, estriate, white. Odor indistinct.

Basidiospores [80/4/4] (11.0–) 11.5–14.0 (–14.5) × (7.5–) 8.0–10.0 (–10.5) µm, Q = (1.33–) 1.38–1.63 (–1.67), Q m = 1.52 ± 0.09, ellipsoid to elongate, inamyloid, thin-walled, hyaline, smooth; apiculus small about 1 µm long. Basidia 40–49 × 12–14 µm, clavate, 4-spored; sterigmata 4–6 µm long, basal septa clamped. Lamellar trama bilateral. Mediostratum 30–40 µm thick, composed of filamentous hyphae and ellipsoid to subfusiform inflated cells. Lateral stratum consisting of abundant ellipsoid to elongate ellipsoid inflated cells and scattered thin-walled regular hyphae, 3–7 µm wide. Subhymenium 28–40 µm thick, with 2–3 layers of pyriform inflated cells, 10–22 × 7–18 µm. Lamellar edge somewhat gelatinized, composed of hyaline, numerous subglobose, clavate or pyriform inflated cells 20–40 × 10– 20 µm and 3–5 µm wide filamentous hyphae, single or in short chains, running parallel to the lamellar edge. Pileipellis 30–80 µm thick; upper layer 20–40 µm thick, slightly gelatinized, filamentous hyphae 1–4 µm wide, hyaline, radially arranged; lower layer 15–40 µm thick of filamentous hyphae 2–8 µm wide, colorless, radial or interwoven, compact. Pileus context made up of abundant thin-walled inflated cells, 45–90× 20−40 µm; mixed with filamentous hyphae 3–5 µm diam, thick-walled (about 1–1.5 µm thick), clamped. Volval remnants on the stipe base dominantly composed of abundant longitudinally arranged 3–7 µm wide, colorless, thin-walled filamentous hyphae; scattered to fairly abundant inflated cells, subglobose to ellipsoid, 40–90 × 25–55 µm, colorless, thin-walled. But inflated cells of the outer layer of the volval remnants more abundant than the inner layers. Stipe trama mainly composed of longitudinally arranged, long, clavate, 90–200 × 25–45 µm terminal cells and 2–10 µm wide filamentous hyphae. Annulus consisting mainly of radially arranged hyphae, 2.5–7 µm wide, colorless, thin or slightly thick-walled; inflated cells scarce, ellipsoid to elongate, clavate to broad clavate, 20–40 × 9–15 µm, colorless, thin-walled, often single and terminal. Clamps present in all tissues of basidiomata.

Known distribution and habitat:— CHINA. Anhui, Liaoning, Yunnan province. Solitary to gregarious on soil in needle woods of P. armandii , P. yunnanensis or mixed forests dominated by Q. fabri , Rhododendron sp. and P. yunnanensis , elev. 2200–2269 m, July to October.

Other specimens examined:— CHINA. ANHUI PROVINCE: Jinzhai County, elev. 939 m, 19th July 2017, Y. J . Hao 1432 ( HKAS 100579 ) [GenBank Acc. No.: MH 508293 ( ITS); MH 486432 ( LSU)]; Same location, elev. unknown, 25th July 2017, Y. J . Hao 1570, ( HKAS 100633 ) [GenBank Acc. No.: MH 486433 ( ITS); MH 508294 ( LSU)] ; LIAONING PROVINCE: Huanren County, elev. 397 m, 26th August 2015, Q . Cai 1429, ( HKAS 92048 ) [GenBank Acc. No.: MH 508296 ( ITS); MH 486435 ( LSU)]. Benxi City, elev. unknown, Collector unknown ( HKAS 92007 ) [GenBank Acc. No.: MH 508295 ( ITS); MH 486434 ( LSU)] . YUNNAN PROVINCE: Heqing County, Xiqiao Town , 26°18′09”N, 100°10′41”E, elev. 2250 m, 24th September 2015, L. P . Tang 2269 (MHKMU-Tang2269) [GenBank Acc. No.: MT 108789 ( ITS); MT 138688 ( LSU)]; Shizong County, Junzi Mountain , 24°38′39″N, 104°9′12″E, elev. 2304 m, 8th August 2019, Y. J . Pu 050 (MHKMU-Pu050) [GenBank Acc. No.: MT 108791 ( ITS); MT 138690 ( LSU)]; Wuding County, Shizi Mountain , elev. 2200 m, 3rd October 2011, L. P . Tang 1565 (MHKMU-Tang1565) [GenBank Acc. No.: MT 108788 ( ITS); MT 138687 ( LSU)]; Yulong County, Yufeng Mountain , Z. L . Yang s. n. ( HKAS 29519 ) [GenBank Acc. No.: AF024459 ( LSU)] .

Figures

FIGURE 3. Basidiomata of Amanita fense. a–c: MHKMU-Huang174 (holotype), Photos by H.Y. Huang. d: HKAS 100633, Photos by Y.J. Hao. e–f, HKAS 100579, Photos by Y.J. Hao. g, j: MHKMU-Tang1565, Photos by L.P. Tang. h, k: MHKMU-Tang2269, Photos by L.P. Tang. i, l: MHKMU-Pu050, Photos by Y.J. Pu.

FIGURE 4. Microscopic features of Amanita fense (MHKMU-Huang174). a. basidiospores; b. basidia and elements of subhymenium; c. cells of the lamellar edge. Bars: a = 3 µm, b–c = 10 µm. Drawings by M. Mu.