Wolfiporia pseudococos F. Wu, J. Song & Y.C. Dai          

MycoBank number: MB 818729 Facesoffungi number: FoF 2961

Etymology: referring to the similarity of Wolfiporia cocos.

Holotype: BJFC01938

Basidiocarp annual, resupinate, soft corky and without odour or taste when fresh, corky to fragile when dry, up to 10 cm long, 4 cm wide, 6 mm thick at centre. Margin thin, usually pores extend to the very edge. Pore surface cream to ash-grey when fresh, becoming pinkish-buff to cinnamon-buff when dry, not glancing; pores round, 1–3 per mm; dissepiments thick, even to slightly lacerate. Subiculum cinnamon-buff, corky, up to 1.5 mm; tubes corky to fragile, buff, up to 4.5 mm long. Hyphal system dimitic in all parts, generative hyphae with simple septa, skeletal hyphae dominant, all hyphae IKI-, CB-, weakly inflated in KOH. Subicular hyphal structure homogeneous, hyphae strongly interwoven; generative hyphae occasionally present, hyaline, thin-walled, occasionally branched, frequently simple septate, 4–6 µm in diam.; skeletal hyphae dominant, hyaline, thick-walled with a distinct wide lumen, usually winding, frequently branched, occasionally simple septate, 5–7 µm in diam. Tramal generative hyphae frequent, hyaline, thin-walled, occasionally branched, frequently simple septate, 3–5 µm in diam.; tramal skeletal hyphae frequent, hyaline, thick-walled with a wide lumen, winding, occasionally branched and simple septate, 4–6 µm in diam. Cystidia absent, cystidioles present; Basidia clavate, with four sterigmata and a basal simple septum, 18–25 × 10–14 µm, basidioles in shape similar to basidia but slightly smaller. Basidiospores ellipsoid to broadly ellipsoid, tapering at apiculus, hyaline, thin-walled, IKI-, CB-, (7.6–) 7.9–9.5 (–9.7) ´ (2.9–) 3–3.8 µm, L = 8.55 µm, W = 3.17 µm, Q = 2.7 (n = 30/1).

Specimen examined: CHANA, Hainan Province, Ledong County, Jianfengling Nature Reserve, On dead angiosperm tree, 1 June 2015, Dai 15269 (BJFC019380, holotype). GenBank numbers ITS:KX354451.

Notes: The phylogenetic analysis of ITS sequence shows that the new species, Wolfiporia pseudococos, is closely related to W. cocos (F.A. Wolf) Ryvarden & Gilb, the type species of the genus Wolfiporia. Sequence data from three specimens of W. Cocos also clustered in a distinct lineage with strong support (100% BS, 1 BYPP), and the sequence of the new species formed a terminal lineage. Morphologically, Wolfiporia pseudococos is distinguished from W. cocos by the presence of cystidioles and larger basidiospores (7.9–9.5 × 3–3.8 µm vs. 6.5–8.1 × 2.8–3.1 µm). In addition, Wolfiporia cocos usually grows on conifers in temperate areas, but Wolfiporia pseudococos has a distribution in tropics and growing on angiosperm trees.

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. The new species Wolfiporia pseudococos described in this study is highlighted in blue. The tree was rooted with Grifola sordulenta and Laetiporus sulphureus.

 

Fruiting body of Wolfiporia pseudococos (BJFC01938, holotype) (photo by Y.C. Dai)

 

Microscopic structures of Wolfiporia pseudococos (BJFC01938, holotype). a Basidiospores. b Basidia and basidioles. c Cystidioles. d Hyphae from trama. e Hyphae from subiculum (drawings by F. Wu).