Cortinarius subsanguineus T.Z. Wei, M.L. Xie & Y.J. Yao.
Fungal Name number: FN 570648; Facesoffungi number: FoF06102.
Basidiocarps gregarious. Pileus 2.5–6 cm diam, firstly hemispherical, then convex, finally convex-applanate to applanate, slightly umbonate at center; margin decurrent to straight; surface dull orange-red (Vinaceous-Rufous), rust red (Dragon’s-blood Red) to red (Scarlet) to with persistent dark red (Ox-blood Red) minute foccose squamules from universal veil, margin paling to orange-red (Coral Red to Orange Rufous). Lamellae adnate to emarginate-adnate, up to 5 mm wide; red (Scarlet) when young, rust red (Dragon’s-blood Red) when mature, close, with lamellulae. Stipe 5.0–10.0 × 0.5–0.9 cm, central, cylindrical, base thickening to 1.5 cm diam; surface reddish orange (orange Rufous) when young, with rust tint when mature, with rust red foccules from universal veil; rough, solid to soft. Cortina reddish at frst, fnally rust red from the mature basidiospores. Context up to 4 mm thick at center, pale red to dull red, feshy. Smell not distinctive. Taste mild. Spore print rust brown. Chemical reaction with 20% KOH blackish red at all parts. Fluorescence reaction under ultraviolet light indistinct. Basidiospores (6–)6.5–8(–9) × (4–)4.5–5.5(–5.7) μm, Q =1.4–1.6 (x̅=1.5); ellipsoid, yellow–brown to brown, minutely to moderately verrucose. Basidia 26–31 × 6–8 μm, clavate, thin-walled, mostly subhyaline, with four sterigmata. Lamella margin heterogeneous, with sterile cells, 20–26×5–7 μm, clavate, subhyaline, thin-walled. Cheilocystidia and pleurocystidia none. Pileipellis of subcylindrical hyaline, 5–15 μm diam, reddish brown to rust brown. Clamp connections present.
Material examined: CHINA, Yunnan Province, Xianggelila County, Bitahai, alt. 3700 m, on ground in mixed forest with Picea sp. and Quercus aquifolioides, 12 August 2008, Tie-Zheng Wei, Xiao-Qing Zhang & Fu-Qiang Yu 134 (HMAS250503, holotype); Xizang Autonomous Region, Bomi County, Gawarong Tample, 29°47′44.56″ N, 95°41′53.87″ E, alt. 3680 m, on ground in mixed forest with Picea sp. and Quercus aquifolioides, 10 September 2014, Tie-Zheng Wei, Jian-Yun Zhuang, Xiao-Yong Liu & Hao Huang 4949 (HMAS253491); Milin County, Nanyigou, 29°02′11.59″ N, 94°14′29.26″ E, alt. 3166 m, on ground in mixed forest with Picea sp. and Quercus aquifolioides, 20 September 2015, Tie-Zheng Wei & Bin-Bin Li 6542 (HMAS275034).
Notes: Cortinarius subsanguineus is a member of section Sanguinei Kühner & Romagn. ex M.M. Moser (Subgenus Dermocybe) and mainly characterized by its orange-red pileus and stipe. Phylogenetically, C. subsanguineus forms a distinct terminal lineage and shows a close relationship with a few red species, e.g. C. harrisonii Ammirati, Niskanen & Liimat., C. neosanguineus Ammirati, Liimat. & Niskanen, C. puniceus P.D. Orton, C. sanguineus (Wulfen) Gray, C. sierraensis (Ammirati) Ammirati, Niskanen & Liimat. and C. vitiosus (M.M. Moser) Niskanen, Kytöv., Liimat. & S. Laine (Fig. 1). However, the ITS sequences of C. subsanguineus difer from the other species in the phylogenetic tree by at least 7 substitutions and indel positions. C. neosanguineus (Niskanen et al. 2013), C. puniceus (Bidaud et al. 1994; Niskanen et al. 2012; Grupo Ibero-insular de Cortinariologos 2014), C. sanguineus (Bidaud et al. 1994; Breitenbach and Kränzlin 2000; Bellù et al. 2004; Niskanen et al. 2012, 2013; Soop 2018) and C. vitiosus (Niskanen et al. 2012) do not have orange-tinged basidiocarps, and furthermore the basidiocarps of C. neosanguineus (Niskanen et al. 2013) and C. puniceus (Bidaud et al. 1994; Niskanen et al. 2012; Grupo Ibero-insular de Cortinariologos 2014) are purplish-tinged. C. harrisonii has a deep orange-red to brownish orange pileus and deep rusty orange stipe, but its basidiospores (4–5 μm wide, Niskanen et al. 2013) are narrower than those of C. subsanguineus. The pileus of C. sierraensis is orange to brownish orange, but lacks red color (Niskanen et al. 2013). Two other species, C. cinnabarinus Fr. and C. phoeniceus (Vent.) Maire, are also similar to C. subsanguineus on account of their red basidiocarps. The basidiospores of the new Chinese taxon are 6–9 × 4–5.7 μm and shorter than that those of C. cinnabarinus (8–10.5 × 4.5–5.5 μm, Bidaud et al. 1994; 7.3–10 × 4.5–5.7 μm, Breitenbach and Kränzlin 2000; 7–10 × 4.5–5.5 μm, Bellù et al. 2004), and larger than those of C. phoeniceus (5.5–8.5×4–4.5 μm, Bidaud et al. 1994; 6–7 × 3.5–4.5 μm, Soop 2018).