Baorangia pseudocalopus (Hongo) G.Wu & Zhu L. Yang, in Wu et al., Fungal Divers 81(1):1–24 (2016)
Pileus 5–13 cm in diam., grayish red (10C4–10C5), grayish rose (13A8), reddish gray (8B2–10B2), reddish brown (8E8–9E9), dry, subtomentose, incurved at the margin when young; context pale yellow (1A3–2A3) to light yellow (2A4– 3A5), 13–18 mm thick, staining pale blue slowly when bruised. Hymenophore decurrent to free, surface pale yellow to light yellow (2A4–3A5), staining grayish blue immediately; pores angular to nearly round, 1/mm, compound; Tubes pale yellow to light yellow (2A4–3A5), 2– 7 mm long (thickness of hymenophore 1/3–1/5 times that of pileal context at the position halfway to the pileus center), staining light blue to grayish blue slowly when bruised. Stipe subcylindrical to obclavate, 6–9×1.5–2.5 cm, pale yellow (1A3–2A3) to buttercup yellow (4A7) at the apex, and grayish red (12B4–12B6), sometimes with pale yellow background at other part, usually covered by reticulations at the upper part or only at the apex; context light yellow (2A4– 2A6), yellow to canary yellow (2B7–2B8), staining pale blue when young; basal mycelia white. Macrochemical reaction not observed.
Basidia 22–50×8–14 μm, clavate to narrowly clavate, hyaline in KOH, 4–spored, sometimes 2–spored. Basidiospores 9–12.5 (14) × 4–5 μm [Q= (1.88) 2.1–3 (3.2), Qm =2.52± 0.23], subfusoid and inequilateral in side view with slightly suprahilar depression, ovate to subfusoid in ventral view, brownish-yellowish, smooth, inamyloid. Hymenophoral trama boletoid, hyphae cylindrical, 4–10.5 μm wide. Cheilocystidia 15–33×6–11 μm, ventricose-mucronate to clavate-ventricose with subacute apex, thin walled. Pleurocystidia 27–57×6.5–12.5 μm, fusoid-ventricose to ventricose-mucronate or clavate with subacute apex, thin walled. Pileipellis an interwoven trichodermium composed of brown to yellowish brown filamentous hyphae 5–11 μm in width with terminal cells 25–65×4.5–10 μm, which are almost subcylindrical, sometimes with subacute apex. Pileal trama composed of interwoven hyphae 4–7 μm wide. Stipitipellis hymeniform, 70–100 μm thick, composed of more or less vertically light brown to yellowish brown hyphae; terminal cells 19–42×10–20 μm. Stipe trama composed of parallel hyphae 5.5–9 μm wide. Clamp connections absent.
Habitat: solitary to scattered, in subtropical forests dominated by Pinus spp. or Fagaceae or in mixed forests.
Known distribution: Currently known from China and Japan.
Index Fungorum number: IF 810354
Notes: Baorangia pseudocalopus, under the name of Boletus pseudocalopus by Hongo (1972), is surprisingly phenotypically very similar to Caloboletus calopus (Pers.) Vizzini, but the latter species has bitter taste of the context and distinct reticulations on the stipe (at least at the apex) (Zhao et al. 2014; Hellwig et al. 2002). Phylogenetically, they appear in two different clades (Wu et al. 2014). In Wu et al. (2014), B. pseudocalopus clusters together with B. rubelloides (≡ Boletus bicolor Peck, non Raddi) and Boletus rufomaculatus Both. Morphologically, the latter two have darker pilei (red to purple-red, rusty brown to yellowish brown), and B. rufomaculatus has narrower basidiospores (9.9–13.2×3.3–4.5 μm) (Bessette et al. 2000; Both 1998).
Figure 1: Basidiomata of Baorangia pseudocalopus (HKAS 75739) Scale bars=5 cm