Phellinus sousae Ryvarden, Gomes-Silva & Gibertoni, 2012

Gomes-Silva, Allyne Christina, Ryvarden, Leif & Gibertoni, Tatiana Baptista, 2012, Two new species of Phellinus s. l. from the Brazilian Amazonia, Phytotaxa 67 (1), pp. 55-60 : 57-58

Phellinus sousae Ryvarden, Gomes-Silva & Gibertoni sp. nov. ( Figs. 2 A–F )

MycoBank no.: MB 564297

This species differs from other Phellinus species by numerous setal hyphae, being mostly smooth, but also with scattered protuberances.

Type (designated here): — BRAZIL. Mato Grosso: Aripuanã, Estrada do Rio Branco , on angiosperm tree, April 1978, leg. M.A. Sousa 451 (holotype: INPA 85175 , isotype: O and URM 83858) .

Etymology: —Called after the eager collector M. A. Sousa who left fine selected collections of Phellinus and Inonotus spp. at INPA herbarium in Manaus.

Basidiomata perennial, resupinate, pulvinate with distinct raised margins, in the type up to 10 × 10 cm and 1 cm thick, woody hard upon drying; pores surface dark umber (18) to cigar brown (16), smooth; pores round and regular, 7−8 per mm invisible to the naked eye; margin rounded, smooth and almost vertical, in a few places, zonate and sulcate reminding as if a nodulose pileus is under development; in section with a black zone, up to 1 mm wide between the context and the substrate; tubes concolorous with pores surface, up to 9 mm deep indistinctly stratified; context almost invisible, dark rusty brown, in a few places up to 1 mm thick. Hyphal system dimitic; generative hyphae simple-septate, thin-walled, hyaline, 2−3 µm in diam, skeletal hyphae yellowish brown in KOH, thick-walled, 2.5−4 µm in diam; setal hyphae abundant in trama, smooth to slightly tuberculate, thick-walled and dark brown, 4–6 µm wide, up to 85 µm long; hymenial setae absent; basidia 10−13 × 6−8 µm, clavate, 4-sterigmate, simple-septate at the base; basidiospores, globose, pale yellow to golden yellow in 3% KOH, smooth, thick walled and without reaction in Melzer's reagent, 4.5−5 µm in diam.

Habitat: —Found on unknown angiosperm wood.

Distribution: — Phellinus sousae is know from the state of Mato Grosso and Rondônia, Brazil.

Remarks:—The prominent and unique character of this new species is the numerous setal hyphae, being mostly smooth, but also with scattered protuberances. We interpret them as setal hyphae more than tramal setae since they are of even width and with a rounded apex, while usually tramal setae are considerably wider and with an acute apex ( Ryvarden 2004). The only other Phellinus species with spiny to tuberculate setae or setal hyphae is P. spinescens J. E. Wright & G. Coelho (for a description, see Coelho & Wright 1996, Ryvarden 2004). However, in this species the setae arise in the hymenium, besides that its basidiospores are dextrinoid.

Additional specimens examined: — BRAZIL. Rondônia: Porto Velho, Estação Ecológica de Cuniã , August 2010, leg. A.C. Gomes-Silva s.n. ( URM 83423); February 2011, leg. A.C. Gomes-Silva s.n. ( URM 83422) .

Figures

FIGURE 2. Microscopic features of P.sousae (all from holotype). A. Basidiomata. B, C, D. Section through dissepiments showing setal hyphae. E. Setal hyphae. F. Basidiospores.