Amauroderma rugosum (Blume & T. Nees) Torrend Brotéria, sér. bot.
Facesoffungi number: FoF 05186.
Basidiome annual, stipitate, weakly laccate, corky. Pileus 2.5–3.6 × 2.0–2.4 cm, up to 0.5 cm thick at the base, subreniform, mesopodal; upper surface brownish orange (6C4) to brown (6E8), radially rugose, concentrically sulcate with irregularly ruptured crust, wrinkled towards the edge; margin blunt or wavy, concolorous with the pileus; lower surface greyish orange (5B5). Hymenophore up to 12 mm long, indistinctly stratose; pores initially brownish orange (5C4), bruising brown (6E8), pores circular, 3–5 per mm. Context up to 8 mm thick, duplex, dry; upper layer light brown (5D6), fibrous, composed of coarse loose fibrils; lower layer brown (6E8), corky. Stipe eccentric, sub cylindrical, concolorous with the pileus, 5 × 7 cm.
Basidiospores (n = 20) (9.5– )10.1–10.7–11.6(11.7–) × (–7.7)7.9–8.5–9.4(–9.6) μm (Qm = 1.2, Q = 1.1–1.4, with myxosporium). (7.5–)8.3–9.3–10.4(–10.6) × (5.6–)5.8–6.9–8.0(–8.4) μm (Qm = 1.2, Q = 0.9–1.3, without myxosporium), subglobose, brownish-yellow (5B3), with a brown eusporium, overlaid by a hyaline myxosporium. Pileipellis a hymeniderm, brownish-orange (5C4), clavate like cells, dextrinoid. Context trimitic; generative hyphae (n = 25) (0.5–1.1–2.2) μm, hyaline, thin–walled with clamp connections, rarely seen; skeletal hyphae (n = 25) (1.2–2.5–3.5) μm, thick–walled, nearly solid, sometimes branched, ochre orange white (5A2); binding hyphae (n = 20) (0.6-1.7-2.6) μm, thick-walled, branched, nearly solid, orange white (5A2)
Habitat: Rotten conifer wood, in dry dipterocarp forest and in upper mixed deciduous forest, growing up from soil.
Material examined: LAOS, Xiengkhouang Province, Phoukoud District, Yai village, evergreen forest, 19°58′N-103°00′E, elev. 1120 m, collection date 27 July 2016, collector P. Phengsintham (GACP16072707, GACP16072714). Savvanakhet province, Phin district Phouxang Hae Protected Area, mixed deciduous forest, 16°58′N -105°89′E, elev. 173 m, collection date 23 June 2017, collector P. Phengsintham (GACP17062326, GACP17062328), China, Hainan Province, Jiangfengling Mountain, Coniferous rainforest, 18°44′N-108°51′E, elev. 550 m, 19°12′N 109°42′E, collection date 9 August 2014, collector T.C Wen (GACP14080910, GACP14080952, GACP14080929, GACP14080956, GACP 14081118, GACP14081522). Thailand, Chiang Mai Province, Mushroom Research Center, Coniferous rainforest, 19°20′N- 98°44′E, elev. 770 m, collection date 2014/06/21, collector LS Zha (GACP14062120, GACP14062122, GACP14062124).
Notes: Blume & T. Nees described this species as a Polyporus rugosus on the basis of specimens from Java in 1826. Berkeley (1856) introduced a new species Porothelium rugosum from Brazil and Steyaert (1972) suggested Polyporus rugosus and Porothelium rugosum were similar species based on their morphological descriptions. Polyporus rugosus was transferred to Ganoderma (as G. rugosum) by Patouillard (1889). Patouillard (1894) took up the name Porothelium rugosum Berk. and changed it as Ganoderma sprucei Pat., since he considered that there were already an epithet called “rugosum” in Ganoderma. Torrend (1920) transferred G. sprucei Pat. to Amauroderma (A. rugosum). Porothelium rugosum was synonymized Berk. As Amauroderma sprucei (Pat.) Torrend (Furtado 1968). Thus, it was a problem whether P. rugosum Berk. (= G. sprucei Pat.) and G. rugosum (BI. & Nees) Pat. were similar species. Torrend therefore continued to use ‘sprucei’, the earliest epithet available in Amauroderma. Considering the combination of Porothelium rugosum in Foraminispora the epithet is available. However, Costa-Rezende et al. (2017) proposed Foraminispora, a new genus to accommodate Porothelium rugosum (= Amauroderma sprucei) based on strong morphological and molecular data. According to Index Fungorum and MycoBank, A. rugosum (Blume & T. Nees) Torrend is now a legitimized species characterized by mesopodal and often excentric, or often pleuropodal pileus with subglobose basidiospores. Amauroderma rude (Berk.) Torrend also has a light context and black pileus, but the pores are larger (2–3 per mm), and it is mainly distributed in Australia (Cunningham 1965). Ryvarden & Johansen (1980) provided detailed description of this species and our collections agree well with that description and moreover, the descriptions provided by Chinese authors (Teng (1963, Tai 1979, Zhao et al. 1981, Zhao 1989, Bi et al. 1993, Teng 1996, Zhao & Zhang, 2000). This species is a soil-inhabiting saprobe and usually found on the ground or attached to buried roots in hardwood forests (Baran De 1991) and widely distributed in the tropics, especially in South East Asia. In East Asia it is known from subtropical China, Japan, Taiwan, Northern Thailand, and Vietnam (Núñez & Ryvarden 2000, Hapuarachchi et al. 2018b). (From Hapuarachhi et al. 2018)
Fig. 1 Amauroderma rugosum (GACP16072714). a, b Upper surface. c Lower surface. d Cut surface. e Pores in the lower surface (5×). f–i Spores (100×). j Generative hyphae (100×). k Skeletal hyphae (100×). l Binding hyphae (100×). Scale bars: f–i = 10 μm, j–l = 5 μm.
Hapuarachhi K. K., Karunarathna S. C., Phengsintham P., Kakumyan P., Hyde K. D., & Wen T. C. 2018–Amauroderma (Ganodermataceae, Polyporales)–bioactive compounds, beneficial properties and two new records from Laos. Asian Journal of Mycology, 1(1), 121-136.