Spodocybe microspora L.P. Tang & J. Ma

Ma, Jing, Zhang, Guo-Li, Zhang, Wen-Hao, Pu, Yun-Ju & Tang, Li-Ping, 2024, A contribution to the knowledge of the genus Spodocybe (Hygrophoraceae, Agaricales) in China, Phytotaxa 652 (1), pp. 47-58 : 53-54

Spodocybe microspora L.P. Tang & J. Ma , sp. nov. ( Figs. 2e – g , 3d , 4 b−d)

Chinese name: 小$灰ȅ杯伞

MycoBank:—MB844214

Diagnosis:—Differs from other species of the genus Spodocybe by its red-brown pileus covered with small scales, especially at center; smaller basidiospores and obvious caespitose habit.

Etymology:— “ microspora ” refers to small basidiospores of this taxon.

Holotype:— CHINA. Yunnan province: Shizong prefecture (师※县), Phoenix valley ( Kfflù ), on the ground in an evergreen broad-leafed forest ( Fagaceae Quercus spp. , Ericaceae , and Juglandaceae ), 24°39.47'N, 104°10.43'E, elev. 2130 m, 24 August 2018, Man Mu 127 (MHKMU Mu-127!, GenBank Acc. No. : LSU = ON595777, ITS = ON595768).

Description:— Basidiomata medium, clitocyboid. Pileus 4−5.5 cm diam., funnel-shaped, center deeply depressed, margin wavy, covered with small scales, especially in the center; grey-brown (5C2−3) to cinnamon (6B3−4) when young and gradually deepening to red-brown (6D5−8) with age, center darker; context white (1A1) to grey-white (1B1), thick about 0.2 cm wide. Lamellae decurrent, crowded, cream (1A2) to dirty-white (1B2), 0.1−0.2 cm wide. Stipe 4−5.5 cm long, 0.5−0.7 cm in diam., cylindrical, with small scales when very young, gradually decreasing with age, yellow-brown (4C3) to light brown (4B3), hollow; context dirty-white (1B2). Mycelial hyphae white.

Basidiospores [80/5/3] (3−) 3.5−5 (−5.5) × 2.5−3.5 (−4) μm, Q = (1.14−) 1.17−1.67, Q m = 1.42±0.16, broadly ellipsoid to ellipsoid, hyaline, smooth, thin-walled, inamyloid. Basidia 20−32 × 4−6 μm, clavate, thin-walled, usually 2-spored or 4-spored, occasionally 3-spored; sterigmata 2−5 μm long. Cystidia absent. Lamellar trama subregular, hyaline, consisting of hyphae 2.5–9 μm wide, thin-walled. Pileipellis a cutis, comprised of hyphae 3–13 μm wide, sometimes clavate at the ends, thin-walled or slightly thickened (about 1 μm). Pileitrama comprised of parallel hyphae 3–12 μm wide, thin-walled. Stipitipellis a cutis, comprised of hyphae 3–13 μm wide, thin-walled or slightly thickened (about 1 μm). Stipititrama comprised of parallel hyphae 3–12 μm wide, thin-walled. Mycelial hyphae 2–9 μm wide, thin-walled. Clamp connections present in all tissues.

Habit and habitat:—Usually caespitose, on the ground of pure evergreen broad-leaved forests dominated by Fagaceae , Ericaceae , Juglandaceae , and Rosaceae .

Distribution:— CHINA: Currently known from Yunnan province (Shizong prefecture) at elevations ranging from 2100−2300 m.

Additional material examined:— CHINA. Yunnan province: Shizong prefecture (师※县), Junzishan (OiŦ山), on the ground in evergreen broad-leafed forest( Fagaceae Quercus spp. , Ericaceae , and Juglandaceae ), 24°39.68'N, 104°10.28'E, elev. 2280 m, 24 August 2018, Jun-Mei Niu 080 (MHKMU Niu-080, GenBank Acc. No.: nrLSU = ON595776, ITS = ON595767); same location, on the ground in an evergreen broad-leafed forest ( Fagaceae Lithocarpus dealbatus , Rosaceae Docynia delavayi ), 24°39.09'N, 104°10.37'E, elev. 2140 m, 05 August 2019, Yun-Ju Pu 008 (MHKMU Pu-008, GenBank Acc. No.: nrLSU = ON595778, ITS = ON595769).

Comments:—In Yunnan province, Spodocybe microspora is a rare wild edible mushroom. Local people usually prefer frying this mushroom with chili or cook in soups. It is called as “Yueliangjun”(月亮Oi). “Yueliang” (月亮) means “moon” in Chinese and “jun”(Oi) is “mushroom” in the local language of SW China. “Yueliangjun” refers to the context as white as the moon. The species usually grows in pure evergreen broad-leaved forests, whereas the other three species that are also found in southwestern China ( S. alpina , S. bispora and S. rugosiceps ) are usually associated with conifers.

The main diagnostic characteristics of S. microspora are red-brown pileus (4−5.5 cm diam.), stipe covered with small scales, and small basidiospores. Especially, the red-brown tone pileus of this taxon is quite distinct among several Chinese taxa.

Figures

FIGURE 2. Basidioma of four taxa in Spodocybe from southwest China. a, b S. alpina (MHKMU Zhang-642, holotype); c, d S. bispora (c MHKMU Huang-093, d MHKMU Huang-078); e–g S. microspora (e–g MHKMU Mu-127, holotype); h S. rugosiceps (HKAS 69830) (a, b photos by W.H. Zhang; c, d photos by H.Y. Huang; e–g photos by M. Mu; h photos by L.P. Tang).

FIGURE 3. Basidiospores of four taxa in Spodocybe from southwest China. a S. alpina (MHKMU Zhang-642, holotype); b, c S. bispora (b HKAS 73310, holotype; c MHKMU Huang-093, MHKMU Tang-3049); d S. microspora (MHKMU Mu-127, holotype; MHKMU Pu- 008, MHKMU Niu-080); e S. rugosiceps (HKAS 71071); Bars: a–e = 20 μm. (a–e photos by J. Ma).

FIGURE 4. Microscopic features of Spodocybe alpina and S. microspora a, b Basidia. c, d Pileipellis. a from S. alpina; b–d from S. microspora. Bars: a, b =20 μm, c, d = 40 μm. (a–d photos by J. Ma).