Basidiomata small-sized. Pileus 2.5–3.5 cm broad, convex or plano-convex; lamellar edge entire; at centre brownish orange (6C8) abruptly paler to light orange (5A5) at margin; surface dry, velutinous or rimose, staining absent; context white, staining absent. Hymenophore lamellate, decurrent; lamellae subdistant with lamellulae, ventricose, intervenose to anastomosing, pastel yellow (1A4), staining absent. Stipe 3.5–5 cm long, 0.3–0.4 cm wide, mostly equal, venose light orange, staining absent; context solid, white, slightly blue at first, later become reddish orange (7A8). Basal mycelium white. Macrochemical reactions: with NH4OH, browning on pileus and stipe. Basidiospores [100/2/2] (6.9–)7.2–8.4–9.7(–10.8) × (4.2–)4.5–5.2–5.8(–6.2) μm, Q = (1.43–)1.49–1.62–1.81(–1.88), subovoid to elliptical, greyish yellow (1B3) in 5% KOH, smooth under light microscope but with bacillate ornamentation under SEM. Basidia (27.7–)27.8–30.9–33.8(–33.8) × (7.8–)7.9–9.4–10.5(–10.5) μm, clavate, hyaline, 4-spored. Cheilocystidia (47.5–)47.7–66.4–81(–81.1) × (12.1–)12.1–15–18.9(–18.9) μm, broadly clavate. Pleurocystidia (58.1–)58.8–76–91.7(–91.8) × (12.6–)12.7–15.9–19.3(–19.4) μm, utriform to sublageniform. Hymenophoral trama 125–250 μm thick, regular composedof 12–15 μm wide cylindrical, smooth, hyaline hyphae. Pileipellis interwoven trichoderm with terminal cells 24–52 × 9–13 μm, granular content present, with abundant cell wall encrustations pigment visible in aqueous Congo Red, also in sub-terminal cells. Pileus trama made of hyaline 10–25 μm wide. Stipitipellis 75–125 μm thick, with parallel hyphae and caulocystidia (27.0–)27.3–49.6–69.5(−69.7) × (12–)12–16.1–19.5(–19.5) μm, clavate, hyaline, smooth. Stipe trama parallel, cylindrical, hyaline hyphae 12.5–15 μm wide. Clamp connections absent in all tissues. (Figs. 1-2)
MycoBank number: MB 827268, Facesoffungi number: FoF 04844.
Etymology: subrubeolus refers to the reddish brown pileus as well as to the close relationship with P. rubeolus.
Holotype: Thailand. Chiang Mai Province, Mae-on District, Mae Kam Pong, elev. 1300 m, 12/06/2016, Boontiya Chuankid, BC022 (MFLU16–2229).
Habit, habitat and distribution: Solitary to gregarious on the ground in broad-leaved forest dominated by either Fagaceae or Dipterocarpaceae. Currently only known from Thailand.
Specimen examined: Thailand. Chiang Mai province, Meuang District, Doi Suthep-Pui National Park, N18°48.0′–E98°55.8′, elev. 720 m, 17/05/2015, O. Raspé, OR0612 (CMUB).
Fig. 1 Basidiomata of Phylloporus subrubeolus (holotype, BC022) in the field. Scale bars = 1 cm.
Fig. 2 Micro-morphological characters of Phylloporus subrubeolus. a Basidiospores. b Basidia. c Cheilocystidia. d Pleurocystidia. e Pileipellis. f Caulocystidia. Scale bars: a = 10 μm; b–d, f = 20 μm; e = 20 μm. All drawings were made from the type (BC022).
Chuankid B, Vadthanarat S, Hyde KD, Thongklang N, Zhao R, Lumyong S and Raspé O 2019 – Three new Phylloporus species from tropical China and Thailand. Mycological Progress, 18(5), pp.603–614.