Fomitopsis flabellata Soares & Gibertoni

MycoBank number: MB 817408 Facesoffungi number: FoF 2958

Etymology: flabella (Latin) = The name refers to the fan-shaped basidiomata.

Holotype: URM 89405

Basidiomata annual, biannual, pileate, dimidiate, solitary or in small groups or clusters. Pileus 0.2–2 cm wide, up to 2 cm long, 0.3 mm thick at base, upper surface purple (9.1E purple) when fresh and dried, azonate to zonate, glabrous to slightly velutinate. Margin obtuse, entire. Pore surface pinkish-brown to lilac-violaceous (9.4D pinkish-brown, 11.5E lilac violaceous), pores round to angular (3–4 mm), dissepiment thin and entire. Context purple brownish (9.1F brownish), 0.1 mm thick.

Basidiospores cylindrical to sub-cylindrical, 4–5 (6.5) × 2–2.5 μm, smooth, thin-walled, IKI–. Basidia clavate with four sterigmata, 8‒10 (12) × 4–5 μm. Hyphal system trimitic, generative hyphae clamped, thin-walled, 2–3 μm in diam.; skeletal hyphae dominant, thick-walled, hyaline, 3–5 μm in diam.; binding hyphae thick-walled, hyaline, 1.5–2.5 μm in diam. Cystidia absent.

Specimens examined: BRAZIL, AMAPÁ: Porto Grande, Floresta Nacional do Amapá, October 2014, A. Soares (URM 89405, holotype; Isotype in O). BRAZIL, Amapá: Porto Grande, Floresta Nacional do Amapá, September 2013, A.M. Soares (URM 84210). GenBank numbers ITS:KX423688; LSU:KX423686.

Notes: Fomitopsis flabellate can be recognized by the small, usually fan-shaped, coriaceous, brown-vinaceous basidiomata. Fomitopsis lilacinogilva (Berk.) J.E. Wright & J.R. Deschamps and F. cupreorosea (Berk.) Carranza & Gilbn. have a similar colour, but differ by the larger and thicker basidiomata (2‒20 × 2‒9 × 0.5 × 10 cm; 5−16.5 × 2.6−10.3 × 0.3−2.5 cm, respectively). Besides, the pores in F. lilacinogilva are slightly labyrinthiform (1−2 mm) and sub-daedaleoid, becoming sinuous-daedaleoid in F. cupreorosea (1−3 mm), while in F. flabellata they are round to angular. Fomitopsis flabellata is placed as a basal taxon of the Rhodofomitopsis sensu stricto, but with low statistical support. For the time being, we prefer to keep this species in Fomitopsis until new sequences are added to the Antrodia clade phylogeny.

Maximum likelihood phylogenetic tree of the concatenated ITS1, 5.8S, ITS2 and partial 28S rDNA sequences. Bootstrap supporting values (1,000 replicates) and posterior probabilities (PP) from Bayesian analysis to each node are shown from left to right. Only bootstrap values above 50% and PP above 0.75 are provided. The new species described in this study are highlighted in blue. The tree was rooted with Grifola sordulenta and Perenniporia ochroleuca.


Fomitopsis flabellata (URM89405, holotype). a Abhymenial surface. b Hymenial surface. c Pores. d Hyphae context. e Basidiospores. Scale bars: a, b = 1 cm, c = 2 mm, d = 20 m, e = 5 m (photos by R.L. Alvarenga).