Phlebopus portentosus Boedijn, Sydowia 1951
Creators: name: Xie, Hui-Jing
name: Zhang, Chun-Xia
name: He, Ming-Xia
name: Liang, Zhi-Qun
name: Deng, Xiao-Hua
name: Zeng, Nian- Kai
Publisher: name: Zenodo
Year: 2021
Subjects: Biodiversity
Taxonomy
Fungi
Basidiomycota
Agaricomycetes
Boletales
Boletinellaceae
Phlebopus
Phlebopus portentosus

description: Phlebopus portentosus (Berk. & Broome) Boedijn, Sydowia 5(3–6): 218, 1951 (Figs. 4, 6)   
 Description:— Basidiomata medium to very large. Pileus up to 18 cm diam, subhemispherical, convex, plano-convex to applanate; margin decurved, sometimes revolute when old; surface dry, nearly glabrous, yellowish brown (3B6), brown (4C7) to dark brown (4C8); context about 2 cm thick in the center of the pileus, light yellow, sometimes bluing when injured. Hymenophore poroid, depressed around apex of stipe; pores yellow (3A6), almost to round, yellowish brown (3B6), about 0.3 mm diam, unchanging in color when injured; tubes 1–1.5 cm in length, yellow (2A6), unchanging in color when injured. Stipe 8–10.5 × 2.5–4 cm, central, subcylindrical or subclavate, solid, base slightly enlarged; surface dry, nearly glabrous, brown (4C8) to brownish black (4E8); context light yellow (1A5), unchanging in color when injured; annulus absent; basal mycelium yellow (1A6). Odor indistinct.   
 Basidia 18–30 × 10–14 μm, clavate, thin-walled, 4-spored, colorless in KOH, yellow in Melzer’s reagent; sterigmata 4–5 μm long. Basidiospores [60/3/3] 6–9(–10) × (4.5–)5–7(–8) μm, Q = (1–)1.1–1.4(–1.5), Qm = 1.26 ± 0.11, broadly ellipsoid, slightly thick-walled (up to 0.5 μm), yellowish brown in KOH, yellowish brown in Melzer’s reagent, smooth. Hymenophoral trama composed of thin- to slightly thick-walled (up to 0.8 μm) hyphae, 3–10 μm wide, colorless to light yellow in KOH, yellow to brownish yellow in Melzer’s reagent. Cheilocystidia 13–27 × 4–10 μm, pyriform, subfusiform or fusiform, thin-walled, colorless to light yellow in KOH, yellow to brownish yellow in Melzer’s reagent. Pleurocystidia 15–28 × 7–13 μm, pyriform, subfusiform or fusiform, thin-walled, colorless to light yellow in KOH, yellow to brownish yellow in Melzer’s reagent. Pileipellis a trichoderm 130–200 μm wide, composed of thin- to slightly thick-walled (up to 1 μm) hyphae, light yellow in KOH, yellow to brownish yellow in Melzer’s reagent, 3–9 μm in width; terminal cell 15–36 × 3–8 μm, clavate or subcylindrical, subfusiform or fusiform, with obtuse apex. Pileal trama made up of hyphae 3–14 μm in diam, slightly thick-walled (1 μm), colorless to light yellow in KOH, yellow, yellowish brown, reddish brown in Melzer’s reagent. Stipitipellis a trichoderm-like structure 90–150 μm wide, composed of thin- to slightly thick-walled (up to 0.5 μm), 3–6 μm wide, light yellow in KOH, yellow to brownish yellow in Melzer’s reagent, emergent hyphae with subfusiform, fusiform or clavate terminal cells (15–31 × 3–6 μm). Stipe trama composed of cylindrical, colorless to light yellow in KOH, yellow, yellowish brown, reddish brown, slightly thick-walled (up to 1 μm), parallel hyphae 3–14 μm wide. Clamp connections present in all tissues.   
 Habitat:—Solitary or scattered under Eucalyptus tereticornis Smith or Ficus microcarpa L. f.   
 Known distribution:—Southwestern and southern China; Sri Lanka (Pegler 1986), Thailand (Sanmee et al. 2003).   
 Specimens examined:— CHINA. Hainan Province: Haikou City, Jinniuling Park, elev. 20 m, 22 May 2008, N. K . Zeng 22 (FHMU1); Wanning City, Xinglong Tropical Oark, elev. 115 m, 25 May 2013, N. K . Zeng 1186 (FHMU753); same location, 7 July 2013, N. K . Zeng 1248 (FHMU806); Haikou City, beside the roadway, elev. 15 m, 13 August 2019, N. K . Zeng 5041 (FHMU5934). Yunnan Province: Kunming City, bought in the market, 16 August 2016, N. K . Zeng 2779 (FHMU1768); Jinghong City, artificial cultivation, 4 February 2021, C . X. Zhang s.n. (FHMU5936, 5937, 5938).   
 Notes:—Our specimens identified as P. portentosus are well characterized by a large fruitbody with a yellowish brown, brown, dark brown pileus, a brown, brownish black stipe, a light yellow context sometimes bluing when injured, broadly ellipsoid basidiospores, terminal cells of pileipellis mostly subfusiform or fusiform, and a distribution in tropical Asia. The morphological features of the Chinese collections match well with those of P. portentosus from Sri Lanka (Pegler 1986), except that the cystidia were not observed by Pegler (1986) whereas they are common in the Chinese specimens (Fig. 6c, d).   
 Morphologically, P. portentosus is very similar to P. roseus, a species originally described from Sichuang Province of southwestern China. However, P. roseus has a rose pink to reddish stipe, tubular hymenophore with nested angular pores of multiple sizes, and a distribution in subtropical China (Mei et al. 2020).
description: Published as part of Xie, Hui-Jing, Zhang, Chun-Xia, He, Ming-Xia, Liang, Zhi-Qun, Deng, Xiao-Hua & Zeng, Nian- Kai, 2021, Buchwaldoboletus xylophilus and Phlebopus portentosus, two non-ectomycorrhizal boletes from tropical China, pp. 137-154 in Phytotaxa 520 (2) on pages 147-149, DOI: 10.11646/phytotaxa.520.2.2, http://zenodo.org/record/5508807