Boletales » Boletaceae » Baorangia

Baorangia pseudocalopus

Baorangia pseudocalopus (Hongo) G.Wu & Zhu L. Yang, in Wu et al., Fungal Divers 81(1):124 (2016)


Pileus 513 cm in diam., grayish red (10C410C5), grayish rose (13A8), reddish gray (8B210B2), reddish brown (8E89E9), dry, subtomentose, incurved at the margin when young; context pale yellow (1A32A3) to light yellow (2A43A5), 1318 mm thick, staining pale blue slowly when bruised. Hymenophore decurrent to free, surface pale yellow to light yellow (2A43A5), staining grayish blue immediately; pores angular to nearly round, 1/mm, compound; Tubes pale yellow to light yellow (2A43A5), 27 mm long (thickness of hymenophore 1/31/5 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, 69×1.52.5 cm, pale yellow (1A32A3) to buttercup yellow (4A7) at the apex, and grayish red (12B412B6), sometimes with pale yellow background at other part, usually covered by reticulations at the upper part or only at the apex; context light yellow (2A42A6), yellow to canary yellow (2B72B8), staining pale blue when young; basal mycelia white. Macrochemical reaction not observed.


Basidia 2250×814 μm, clavate to narrowly clavate, hyaline in KOH, 4spored, sometimes 2spored. Basidiospores 912.5 (14) × 45 μm [Q= (1.88) 2.13 (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, 410.5 μm wide. Cheilocystidia 1533×611 μm, ventricose-mucronate to clavate-ventricose with subacute apex, thin walled. Pleurocystidia 2757×6.512.5 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 511 μm in width with terminal cells 2565×4.510 μm, which are almost subcylindrical, sometimes with subacute apex. Pileal trama composed of interwoven hyphae 47 μm wide. Stipitipellis hymeniform, 70100 μm thick, composed of more or less vertically light brown to yellowish brown hyphae; terminal cells 1942×1020 μm. Stipe trama composed of parallel hyphae 5.59 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: IF810354

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 (9.913.2×3.34.5 μm) (Bessette et al. 2000; Both 1998).


Figure 1: Basidiomata of Baorangia pseudocalopus (HKAS 75739) Scale bars=5 cm