Ganoderma orbiforme (Fr.) Ryvarden
Index Fungorum number 464692; Facesoffungi number: FoF05657
Basidiome annual to perennial, with a distinctly contracted base, weakly laccate, woody. Pileus 8–21 × 5–12 cm, up to 4 cm thick at the base, flabelliform, plano convex, applanate, upper surface; hard, several layers thick, alternating brownish orange (6C8) to light brown (6D4) concentrically zones, crust overlies the pellis, concentrically sulcate zones with turberculate bumps and rivulose depressions, differentiated zone at the point of attachment. Margin with numerous undulations and irregularities, 4 mm thick, rounded and white (4A1) to yellowish white (4A2). Hymenophore up to 3 mm long, indistinctly stratose, orange grey (6B2), pores circular or sub-circular. Context up to 2 cm thick, dry, triplex; lower layer dark brown (7F8), pithy, composed of coarse loose fibrils, soft; upper layer light brown (5D4), woody. Basidiospores (n = 25) (8.2)10.1–10.7–11.4(11.6) × (4.8)5.7–6.5–7.2(7.4) μm, (Qm = 1.6, Q = 1.3–2.1, with myxosporium). (n = 25) (6.8)7.8–8.7–9.6(10.3) × (3.7)4.7–5.4–6.1(6.7) μm (Qm = 1.6, Q = 1.2–2.1, without myxosporium), yellowish-brown (5D8), elongate, eusporium bearing fine, short, and distinct echinulae, overlaid by a hyaline myxosporium, bitunicate. Pileipellis a hymeniderm, dark brown (7F8), composed of apically acanthus like branched cells, dextrinoid. Context trimitic; generative hyphae (n = 25) (0.8–2.2–2.5) μm in width, thin-walled, hyaline; skeletal hyphae (n = 28) (1.9–3.7–4.9) μm in width, light brown (5D6), thick-walled; binding hyphae (n = 28) (1.6–3.4–7.2) μm in width, light brown (5D6), thick-walled, branched, intertwined the skeletal hyphae. (Fig 1)
Habitat: On a decaying hardwood log, accompanied in humus-rich soil with over heavily rotted litter on the ground, producing basidiomata from summer to late autumn.
Specimens examined: LAOS, Xiengkhouang Province, Phoukoud District, Ngod Phae Village, Evergreen rainforest, 19°53′N–103°22′E, elev. 1141 m, 14 June 2014, P. Phengsintham (GACP14061420, GACP14061414). CHINA, Hainan Province, Jiangfengling Mountain, Coniferous rainforest, 18°N–109°E, elev. 1350 m, 09 August 2014, T.C Wen (GACP14081232, GACP14081235). THAILAND, Chiang Mai Province, Mushroom Research Center, Coniferous rainforest, 19°20′N–98°44′E, elev. 770 m, 12 June 2015, K.K Hapuarachchi (GACP15061260, GACP15061265, GACP15061266).