Entoloma coccineum T.H. Li, J.H. Xing & X.S. He, 2021

Xing, Jia-Hui, He, Xin-Sheng, Li, Tai-Hui, Li, Chuan-Hua & He, Xiao-Lan, 2021, A slender red species of Entoloma (Entolomataceae) from China, Phytotaxa 498 (2), pp. 104-112 : 107-109

Entoloma coccineum T.H. Li, J.H. Xing & X.S. He , sp. nov. ( Fig. 2 )

MycoBank No: MB 836073.

Diagnosis:—Morphologically similar to Entoloma haematinum , but differs in larger basidiospores and darker or less orange pileus, characterized by small and slender basidiomata with orange red to scarlet or brilliant red pileus, deeply decurrent lamellae, and cuboid basidiospores 7–11 μm.

Etymology:— coccineum (Lat.) , scarlet, referring to the scarlet red color of the pileus.

Type:— CHINA. Sichuan Province, Mianyang City , Beichuan Qiang Autonomous County, Tongkou Town , Zhandou Village , on soil in bamboo groves, 104°33′ E, 31°46′ N, 29 August 2019, He Xin-Sheng ( GDGM 78247 holotype!) GenBank ITS: MT 472568 , nrLSU: MT 472566 .

Description:— Pileus 5–13 mm wide, hemispherical at first, becoming convex to nearly plane with a shallow central depression and slightly wavy margin in age, surface dry, smooth to weakly rugulose, faintly pellucid towards margin, scarlet red, flame red to yellowish red or orange red (6A5–7, 7A5–8, 8A4–8 to 9A7). Lamellae deeply decurrent, yellowish white to pale orange (5A1–3 and 6A2), unequal, with 2–3 tiers of lamellulae, margins entire and concolorous with faces. Stipe 10–25 × 0.5–2 mm, very slender, fragile, centrally attached, cylindrical, often curved, almost concolorous with pileus, somewhat translucent, glabrous, with whitish basal mycelium. Odor and taste not distinctive.

Basidiospores [50/2] 7–11 × 7–11 μm in profile, distinctly cuboid, 4–5-angled, mostly 4-angled, thin-walled. Basidia 29–44 × 11–16 μm, clavate, 4-spored (rarely 2–spored), thin-walled; sterigmata 2–3 μm long. Cheilocystidia 20–35 × 6–10 μm, abundant, clavate to narrowly clavate, hyaline, thin-walled. Pleurocystidia absent. Pileipellis a cutis of cylindrical hyphae 7–13 μm wide, with scattered ascending clavate terminal elements 12–25 μm wide, with orange-yellow to orange-red plasmatic pigment. Lamellae trama comprising subparallel hyphae, cylindrical, 4–13.5 μm diam. Stipitipellis a cutis composed of thin–walled hyphae, 5–11.5 μm wide, with pale orange-yellow pigment. Caulocystidia absent. Clamp connections absent in all tissues.

Habitat and distribution:—Scattered or in small groups on soil in bamboo grove; only known from the type locality in Sichuan Province of China.

Additional materials examined:— CHINA. Sichuan Province, Mianyang City, Beichuan Qiang Autonomous Region, Tongkou town , Zhandou Village , on soil, 104°33′ E, 31°46′ N, 29 August 2019, Xin-Sheng He, GDGM 78246 (nrLSU: MT 472565 ) , GDGM 76958 (ITS: MT 472564 , nrLSU: MT 472567 ) .

Figures

FIGURE 2. Macro- and microscopic features of Entoloma coccineum. a–c: Basidiomata. d, h, i: Basidiospores (d under light microscope; h, i, under scanning electron microscope). e. Cheilocystidia. f–g: Basidia. j–k: Pileipellis. Bars: d, e = 20 μm; f, g = 10 μm; j, k = 40 μm. a–c photos by Xin-Sheng He; d–k photos by Jia-Hui Xing.