Name: Favolus brasiliensis
Author: (Fr.) Fr.
Citation: Linnaea 5: 511 (1830)
Deprecated Synonyms: Favolus tenuiculus P. Beauv. nom. amb., Polyporus tenuiculus (Beauv.) Fr., Polyporus tenuiculus (P. Beauv.) Fr., Merulius daedaleus Link, Polyporus dermoporus Pers., Favolus flaccidus Fr., Favolus hepaticus Klotzsch, Favolus tessellatus Mont., Favolus tessulatus Mont., Favolus fissus Lév., Favolus peltatus Lév., Favolus alutaceus Berk. & Mont., Favolus lacerus Fr., Favolus sundaicus Fr., Favolus lacer Fr., Favolus giganteus Mont., Hexagonia rhombipora Mont., Favolus hispidulus Berk. & M.A. Curtis, Favolus scaber Berk. & Broome, Polyporus lenzitoides Berk., Favolus fimbriatus Speg., Favolus paraguayensis Speg., Favolus speciosus Speg., Favolus guarapiensis Roum., Favolus saltensis Speg., Hexagonia wilsonii Murrill, Hexagonia floridana Murrill, Hexagonia fragilis Murrill, Hexagonia subpurpurascens Murrill, Hexagonia subcaperata Murrill, Hexagonia maxonii Murrill, Polyporus palensis Murrill, Hexagonia reniformis Murrill, Hexagonia daedaleiformis Murrill, Hexagonia motzorongensis Murrill, Hexagonia sulphurea Murrill, Hexagonia sulfurea Murrill, Favolus caespitosus Lloyd, Polyporus spegazzinianus Bres., Favolus mollis Lloyd, Favolus lutescens Lloyd, Favolus balansae Bres., Favolus bresadolianus Speg., Favolus bresadolanus Speg., Polyporus arcularioides A. David & Rajchenb., Polyporus bresadolianus (Speg.) Popoff & J.E. Wright
Basidiocarps annual, laterally stipitate, solitary. Pileus reniform, flabelliform to spathulate, applanate, up to 5.5 cm from the base to margin, up to 4.5 cm wide; surface glabrous, radially striate, white in fresh condition, drying cream to brownish orange (10YR6–8/4–8), azonate; margin acute, entire. Stipe cylindrical, up to 7 mm long, up to 5 mm diam. Context leathery to tough-fleshy, thin, white in fresh condition, drying brittle, cream (10YR8–9/4). Pore surface white, pores radially elongated, 2–4 mm long, 1–2 mm wide, dissepiments thin, entire or slightly lacerate. Tubeswhite, up to 4 mm deep. Hyphal system dimitic with gen- erative hyphae and skeletal-binding hyphae. Contextual generative hyphae thin-walled, hyaline, with clamp connec- tions, clamp connections abundantly seen in dried speci- mens, up to 4 μm in diam. Contextual skeletal-binding hyphae thick-walled to solid, occasionally to moderately branched, moderately interwoven, hyaline, non-dextrinoid, 3–5(−6.6) μm in diam. at basal stalk. Tramal generative hyphae same as in context. Tramal skeletal-binding hyphae thick-walled to solid, moderately branched, moderately to highly interwoven, hyaline, non-dextrinoid, 3.5–7 μm in diam. at basal stalk. Pileipellis not well differentiated. Basidia clavate, 4-sterigmate, 20–34 × 6.6–8.5 μm. Basidiospores cylindrical, hyaline, non-dextrinoid, (6–)7– 12 × 2.2–4.6(−4.8) μm, L 0 9.56 μm, W 0 3.53 μm, R 0 2.0– 3.7, r02.75 (n0171/3).
Distribution Tropical areas of Central to South America in El Salvador and Brazil.
Remarks This is quite similar to F. spathulatus in its white, leathery, and flexible basidiocarps with radially elongated and hexagonal pores. However, F. brasiliensis is distinct from F. spathulatus owing to its larger pores and generative hyphae with conspicuous clamp connections.
Specimens examined BRAZIL, Amazonas St., Manaus, N.K. Ishikawa, C.A.A. Cortegano & R. Vargas-Isla, 11 Mar 2011 (INPA 241446); Amazonas St., Manaus, N.K. Ishikawa & R. Vargas-Isla, 7 Apr 2011 (INPA 241447); Amazonas St., Manaus, N.K. Ishikawa & R. Vargas-Isla, 25 Apr 2011 (INPA 241453); Amazonas St., Manaus, N. Maekawa, T. Shirouzu, N.K. Ishikawa & D.L. Komura, 9,Aug 2011 (INPA 241427); Amazonas St., Manaus, D.L. Komura, N.K. Ishikawa & N. Maekawa, 9 Aug 2011 (INPA 241452). El SALVADOR, Cabañas Dep., Cinquera, Parque Ecológico Bosque de Cinquera, K. Sotome & N. Maekawa, 28 Sep 2011 (TUMH 50010); the same place, K. Sotome & N. Maekawa, 28 Sep 2011 (TUMH 50011).
Small basidiocarps with grayish orange to yellowish orange pileus surface, and large and radially elongated pores clearly differentiate this species from other Favolus spp. This species has been considered as a synonym of Polyporus tenuiculus (Ryvarden 1989), but our study reveals that P. tenuiculus sensu lato comprises at least three species. We accept F. roseus as a distinct species, considering its phylogenetic and morphological characters. The holotype of P. tenuiculus seems to be inaccessible, and this must remain an ambiguous name. [emphasis mine]
It is, however, still listed as a synonym on MycoBank. I will try and bring some Neotropical polyporologists into the conversation.