Agaricus trisulphuratus Berk.
Index Fungorum number: IF 164564, MycoBank: MB 164564, Faces of Fungi: FoF01192
Pileus mostly 30–60mmin diam., hemisphaerical, conical, broadly conical, convex, plano-convex, subumbonate when mature, surface dry, covered with acute squamules, floccose, erect at centre and recurved at the margin; golden yellow (5B8), orange, reddish orange (7A8), deep orange (5A8), and fading upon aging or in rain, margin exceeding. Lamellae free, crowded to more crowded, at first white, orange-white (6A2), then greyish-pink, reddish-brown (8E3), greyish-brown (8D3, 6D3), finally brown (7E8), dark brown, edge heteromorphic (colour lighter than those of lamellae). Stipe 20–90× 3–7 mm, cylindrical; hollow; mostly with rhizomorphs at base; smooth and white above the annulus; flaky and shaggy, same colour as the pileus below the annulus, not discolouring on touching. Annulus pendent, same colour with flaking of stipe surface, in most cases difficult to be recognized from those flakes. Context firm, on cutting white in both pileus and stipe, no discolouring on exposure. Odour none or mushroomy. Macrochemical reaction: KOH reaction yellow at pileus, Schäffer’s reaction negative. Basidiospores 5–6 × 3.2–4 μm [x = 5.5 ± 0.6× 3.7 ± 0.3, Q = 1.3–1.8, Qm = 1.48 ± 0.32, n = 20], ellipsoid with suprahilar depression, reddish-brown, smooth, thick-walled, without germ pore. Basidia 12–14× 6–7 (−8) μm, clavate, 4-spored. Cheilocystidia 18–36×6–13 (−15) μm, clavate, cylindrical with tapering base, occasionally with 1 septa, surface spiny in some cases, hyaline. Pleurocystidia absent. Pileipellis a cutis, composed of 3–5 μm diam., long cylindrical, curved, brunched, fine, spinyhyphae. Annulus and stipitipellis consisting of the same hyphae as pileipellis. (Fig. 1 e-f; Fig. 2)
Habitat: mostly solitary, some scattered in small groups in soil.
Specimen examined: THAILAND, Chiang Mai, collection data collector unknown, ZRL1003 (SFSU); Chiang Mai Prov., Chiang Dao Cave, 22 July 2004, collected by Ruilin Zhao, ZRL3089 (BBH19605; SFSU); Chiang Mai Prov., Mae Taeng, Ban Mae Sae Village, on Hwy 1095 near 50 km marker, N19°14. 599′ E98°39.456′, elev. 962 m., 26 June 2005, collected byJennifer Kerekes, ZRL2045 (SFSU); same location, 3 July 2005, collected by Ruilin Zhao, ZRL2087 (BBH19470; SFSU); same location, 18 August 2004, collected by Edward Grand, ZRL2128 (BBH19508; SFSU); same location, 3 June 2006, collected by Ruilin Zhao, ZRL3014 (BBH19531; SFSU); same location, 18 June 2006, collected by Ruilin Zhao, ZRL3070 (BBH19586; SFSU); Chiang Mai Prov., Mae Taeng Dist., Ban Pha Deng Village, N 19°17.123′ E 98°44. 009′, elev. 900 m., 11 August 2004, collected by Kevin D Hyde, ZRL2123 (BBH19502; SFSU); same location, 22 May 2006, collected by Ruilin Zhao, ZRL3002 (SFSU); same location, 29 May 2006, collected by Ruilin Zhao, ZRL3009 (BBH19526; SFSU); same location, 24 June 2006, collected by Ruilin Zhao, ZRL3072 (BBH19588; SFSU); Chiang Mai Prov., Mae Taeng Dist., Tung Joaw Village, forest trail, N19°08.07′ E98°38.90′, elev. 1300 m., 3 August 2004, collected by Edward Grand, ZRL2111 (BBH19491; SFSU); Chiang Mai Prov., Mae Taeng Dist., Ban Pha Deng Village, Pathummikaram Temple, forest trail, N 19°06′28.8″ E 98°44′47.3″, elev. 1050 m., 12 June 2004, collected by Ruilin Zhao, ZRL3054 (BBH19570; SFSU); CHINA, Yunnan province, Dali, Cangshan Mountain, Yunnongfeng, 24 July 2014, collected by Sun SY, Bai XM, ZRL2014023 (HMAS273985)., ZRL201 40 24 (HMAS273 93 5 ) . , ZRL2014025 (HMAS273962), ZRL2014026 (HMAS273927) , ZRL2014030 (HMAS273956).
Distribution: Africa, Malaysia, China, Thailand.
Notes: A. trisulphuratus is type species of section Trisulphurati, and common in forests or grasslands in tropical and subtropical areas. This species also has been reported from. In the phylogenetic tree, the samples from Thailand and Malaysia cluster with those from Africa, with strong support. Morphologically, they match the description of Heinemann.