Ramaria xizangensis C. L. Zhao & H. M. Zhou 2024, sp. nov.

Ramaria xizangensis C. L. Zhao & H. M. Zhou sp. nov. Figs 11, 12 Holotype. China, Xizang, Linzhi, Sejila Mountain National Forest Park, 29 ° 64 ' N, 94 ° 71 ' E, elev. 3850 m, gregarious on the humus under Abies, 2 August 2023, CLZhao 31169 (SWFC). Etymology. Xizangensis (Lat.): refers to the locality (Xizang) of the type specimens. Diagnosis. Differed from other species in having flesh pink basidiomata, monomitic hyphal system, generative hyphae with clamp connections, ellipsoid to cylindrical, densely warted basidiospores (9.7–11.8 × 3.9–4.9 µm). Fruiting body. Basidiomata solitary to gregarious, with 8 cm high × 6 cm wide at the widest point, repeat branched dichotomously in 4–5 ranks, flesh pink when fresh, become clay buff with dry; apices obtuse, orange yellow when fresh, becoming fuscous when dry. Stipe ≥ 3 cm high, compound to fasciculate in groups of 5, emerging from a common base, concolorous with the branches. Hyphal structure. Hyphal system monomitic, generative hyphae with clamp connections, branched, walls smooth and hyaline; basal stem with tramal hyphae 4–7 μm wide and inflated ones up to 10 μm, occasionally branched, thin-walled, parallel arranged, hyaline; tramal hyphae of branches 3–4 μm wide. Hymenium. Hymenium all along the basidiomata. Basidia clavate, in a dense palisade, with 4 sterigmata and a basal clamp connection. Basidioles elongated clavate, smooth, hyaline, contents homogeneous, 23.5–34 × 6–7 μm. Spores. Basidiospores ellipsoid to cylindrical, densely warted, with 1–2 several guttulae, IKI –, CB –, 9.7–11.8 (– 12.5) × (3.8 –) 3.9–4.9 (– 5.1) µm, L = 10.69 µm, W = 4.29 µm, Q = 2.49 (n = 30 / 1). Additional specimens examined (paratypes). China, Xizang, Linzhi, Sejila Mountain National Forest Park, 29 ° 67 ' N, 94 ° 74 ' E, elev. 3850 m, gregarious on the humus under Abies, 2 August 2023, CLZhao 31180 (SWFC); on ground in forest of Abies, 2 August 2023, CLZhao 31204 (SWFC).西藏枝瑚菌（Ramaria xizangensis C. L. Zhao & H. M. Zhou）新种 图版11、12 模式标本：采集于中国西藏自治区林芝市色季拉山国家森林公园，北纬29°64′，东经94°71′，海拔3850 m，群生于冷杉（Abies）林下腐殖质中，2023年8月2日，采集号CLZhao 31169，标本馆藏于SWFC。 词源：Xizangensis（拉丁语）：指模式标本的采集地西藏。 分类鉴别特征：本种与其他近缘物种的区别在于：具肉粉色担子果（basidiomata），单系菌丝系统（monomitic hyphal system），生殖菌丝（generative hyphae）具锁状联合（clamp connections），担孢子（basidiospores）呈椭圆形至圆柱形，密被疣状突起，大小为9.7–11.8 × 3.9–4.9 μm。 子实体形态：担子果单生至群生，最高处可达8 cm高、6 cm宽，呈二叉状分枝4–5级；新鲜时肉粉色，干燥后变为土黄色；分枝顶端钝圆，新鲜时呈橙黄色，干燥后变为暗褐色。菌柄（stipe）≥3 cm高，5个为一簇从共同基部发出，与分枝颜色一致。 菌丝结构：菌丝系统为单系，生殖菌丝具锁状联合，分枝，壁光滑且透明；菌柄基部的骨架菌丝（tramal hyphae）宽4–7 μm，膨大的菌丝可达10 μm，偶有分枝，壁薄，平行排列，透明；分枝处的骨架菌丝宽3–4 μm。 子实层：子实层遍布整个担子果。担子（basidia）呈棒状，密集排列成栅栏状，具4个担孢子梗（sterigmata）和基部的锁状联合。拟担子（basidioles）细长棒状，光滑、透明，内含物均匀，大小为23.5–34 × 6–7 μm。 孢子形态：担孢子呈椭圆形至圆柱形，密被疣状突起，具1–2个油滴（guttulae），碘液染色反应阴性（IKI –），棉蓝染色反应阴性（CB –），大小为9.7–11.8 (–12.5) × (3.8–)3.9–4.9 (–5.1) μm，平均长度L=10.69 μm，平均宽度W=4.29 μm，长宽比Q=2.49（n=30/1）。 检视副模式标本：中国西藏自治区林芝市色季拉山国家森林公园，北纬29°67′，东经94°74′，海拔3850 m，群生于冷杉林下腐殖质中，2023年8月2日，采集号CLZhao 31180（SWFC）；生于冷杉林地上，2023年8月2日，采集号CLZhao 31204（SWFC）。