Two new species of Butyriboletus from China Author Fu, Hao-Yu 0000-0001-5529-4964 865001572 @ qq. com; https: // orcid. org / 0000 - 0001 - 5529 - 4964 865001572@qq.com Author Li, Ting 0000-0001-7809-3217 1377090363 @ qq. com; https: // orcid. org / 0000 - 0001 - 7809 - 3217 1377090363@qq.com Author Fan, Li 0000-0001-9887-7086 fanli @ mail. cnu. edu. cn; https: // orcid. org / 0000 - 0001 - 9887 - 7086 fanli@mail.cnu.edu.cn text Phytotaxa 2022 2022-04-29 544 2 207 219 journal article 55787 10.11646/phytotaxa.544.2.7 9c4d80ca-9692-4217-9f6a-de3ab6172c4d 1179-3163 6503921 Butyriboletus sinoregius L. Fan & H.Y. Fu , sp. nov. 2 ( Fig. 4 ) Mycobank :—MB842145 Diagnosis :—differs from the European B. regiu s by the different phylogenetic position, the basidiomes bluing when bruised and the finely tomentose pileus. Etymology :—‘ sinoregius ’; sino , means China , ‘ regius ’ refers to this new Chinese species being similar to B. regius . Holotype :— CHINA . Shanxi Province , Jincheng City, Qinshui County , Zhongcun Forest Farm , on the ground in Fagaceae forest, 35°29′8″N , 112°11′28″E , elev. 1630 m , 22 August 2019 , collected by Hong Liu LH 755 ( BJTC FM755 ) . Description :— Pileus 6.3–7 cm diam., convex to applanate; surface dry, sometimes cracking at centre, finely tomentose, pale purple-red (#ff6b6b), and fading to pale red-orange or grayish orange (#f8f1e2) to margin, margin straight to decurved; context firm and dense, thick, pale yellow (#ffff4d), becoming blue when exposed. Hymenophore (tube layer) surface bright yellow (#ffff1a) to pale yellow (#ffff9a) at first, turning to brownish yellow (#ebc300) when matured, becoming blue when bruised; pores circular to somewhat elongate, 0.3–0.7 mm diam; tubes 4–6 mm deep. Stipe 5.2–6.7 × 1.8–2.3 cm , mostly equal, sometimes slightly widening towards the base, dry, not hollow, pale yellow (#ffff4d), becoming blue when bruised, reticulate; annulus absent; basal mycelium whitish (#ffffff) to soft yellow (#fff281). Odor not distinct. Taste unpleasant, sour and astringent. Basidiospores [60/3/3] 10–15 × 5–5.5μm [Q = 2–2.68, Q m = 2.34 ± 0.34], subfusiform to fusoid-ventricose, subhyaline in KOH. Basidia 27.5–32.5 × 10–12.5μm, clavate, thin-walled, hyaline in KOH, 3–4-spored; sterigmata short. Hymenophoral trama boletoid. Pleurocystidia 25–42.5 × (5–) 7.5–12.5 (–17.5) μm, smooth, thin-walled, hyaline in KOH, barrel-shaped, or utriform to lageniform with subacute apex; cheilocystidia absent. Pileipellis an interwoven trichoderm, 27.5–50 μm thick, composed of interwoven hyphae, 3–5 μm in diam, hyphae yellow greenish brown (#e1f9b1), hyaline in KOH, smooth, thin-walled, terminal cells nearly clavate sometimes with expanding obtuse. Stipitipellis an interwoven trichoderm-like structure, 145–240 μm thick, composed of thin- to slightly thick-walled (up to 1 μm) hyphae with narrowly or broadly clavate, subfusiform or fusiform terminal cells (14–28 × 3.5–6 μm), and some emergent hyphae with clavate or subcylindrical terminal cells. Stipe trama composed of cylindrical, thin to slightly thick-walled (up to 1 μm), parallel hyphae 3–14 μm diam. Clamp connections absent. Habit, Habitat and distribution: Solitary or scattered, on ground in a Fagaceae forest dominated by Quercus sp. , so far only known from Shanxi Province , China . Additional specimens examined: CHINA . Shanxi Province , Jincheng City, Lishan Mountains, 16 July 2020 , collected by Hong Liu LH 929 (BJTC FM1240); ibid. Linfen City, Yicheng Country, Shihe Forest Farm, Songshu Groove, 35°29′35″N , 112°5′41″E , elev. 1960 m , 26 August 2020 , collected by Hong Liu LH1178 (BJTC FM1103).