Ganoderma phyllanthicola J. He & S. H. Li, 2024

He, Jun, Li, Xiao-Jun, Tan, Wan-Zhong, Wu, Xiao-Qu, Wu, Dan, Luo, Zong-Long, Zhou, Qi Wu, Li, E-Xian & Li, Shu-Hong, 2024, Two new species of Ganoderma (Ganodermataceae, Basidiomycota) from Southwest China, MycoKeys 106, pp. 97-116 : 97-116

Ganoderma phyllanthicola J. He & S. H. Li sp. nov.

Fig. 2

Diagnosis.

Differs from other species in the genus by its sessile and coriaceous basidiomata, dark brown to purplish black pileus surface with dense concentric furrows, pale yellow margin, irregular pileipellis cells, broadly ellipsoid to subglobose basidiospores and truncated apex, exospore walls smooth, endospore walls with dense spinules.

Etymology.

The epithet ‘ phyllanthicola ’ refers to the host tree genus Phyllanthus .

Holotype.

China. Yunnan Province., Honghe City , Mengzi County, on living tree of Phyllanthus emblica , alt. 1685 m, Jun He, 26 August. 2019, L 4948 ( HKAS 123776 ).

Description.

Basidiomata annual, sessile and broadly attached, coriaceous, hard corky to woody hard. Pileus single or dimidiate, sub-circular, flabelliform to shell-shaped, applanate, projecting up to 22 cm, 12 cm wide and 1.9 cm thick at base. Pileus surface dark brown (8 F 8), purplish black (8 F 3) to reddish brown (6 F 8) and covered by a thin hard crust, laccate, glabrous and shiny, with dense concentric furrows. Margin pale yellow (4 A 3) to generally concolorous, entire, subacute, slightly wavy. Context up to 0.8 cm thick, homogeneous, cinnamon brown (6 D 7) to chestnut brown (8 E 5), with black melanoid lines, hard corky. Tubes 0.5–1.1 cm long, concolorous with the base of the context, corky, unstratified. Pores 5–7 per mm, circular to subcircular, dissepiments slightly thick, entire; pores surface greyish white (2 B 1) when fresh, orange grey (5 B 2) to pale brown (6 D 6) when bruising and drying.

Hyphal system trimitic. Generative hyphae 1.0–2.0 μm in diameter, colorless, thin-walled, with clamps connections; skeletal hyphae 2.0–5.0 μm in diameter, thick-walled with a wide to narrow lumen or sub-solid, arboriform with few branches, yellowish to golden yellow; binding hyphae 1.0–3.0 μm in diameter, thick-walled, branched and flexuous, pale yellow, scarce; all the hyphae IKI –, CB +; tissues darkening in KOH.

Pileipellis a crustohymeniderm, cells 15–33 × 5–9 μm, thick-walled to sub-solid, composed of irregular, narrowly clavate end cells, straight to flexuose, smooth or with a few small apical protuberances, yellowish to golden-yellow, sometimes with apical granulations, apex slightly amyloid.

Basidiospores ellipsoid to subglobose, apex truncated or subacute, yellowish to yellowish brown, IKI –, CB +, inamyloid; double-walled with distinctly thick walls, exospore wall smooth, endospore walls with interwall pillars; (40 / 2 / 2) (8.5) 9.0–9.6 – 10.0 (11.0) × 6.0–6.8 – 7.0 (7.5) µm, L = 9.65 µm, W = 6.75 µm, Q = (1.24) 1.38–1.52 (1.55), Q m = 1.43 ± 0.07 (including myxosporium). Basidia not observed.

Additional specimens examined.

China, Sichuan Province, Panzhihua City , Miyi County, on a decaying tree of Phyllanthus sp. , alt. 1035 m, Jun-He, 15 August 2023, HL 308 .

Notes.

In the phylogenetic analyses, Ganoderma phyllanthicola is clustered as a sister taxon to G. castaneum with strong statistical support (100 % ML and 1.00 PP, Fig. 1 ). Morphologically, both species share similar characteristics of the sessile basidiomata and non-stratified tubes. However, G. castaneum differs from G. phyllanthicola in having buff and obtuse pileus margin, regular palisade pileipellis, heterogeneous context, smaller basidiospores (6.2–8.5 × 4.2–6.3 μm) with smooth endospore walls, Sun et al. 2022). Ganoderma tropicum and G. philippii have similar homogeneous context, but G. tropicum has a stipitate basidiomata and buff pileus margin, samller basidiospores (6.8–10.0 × 4.0–6.4 μm), and ( Steyaert 1972). Ganoderma philippii has wavy like pileus margin and brown context with black melanoid lines, smaller and obovoid basidiospores (6.0–8.0 × 3.0–4.0 μm, Moncalvo and Ryvarden 1997).

Ganoderma aridicola described from South Africa is similar to G. phyllanthicola in the sessile basidiomata with dark brown pileus surface, homogeneous context, small pores and ellipsoid basidiospores. However, G. aridicola differs by the distinctly stratified tubes and lacks branched or protuberant apical cells ( Xing et al. 2016). Besides, the phylogenetic analyses separated G. aridicola and G. phyllanthicola (Fig. 1 ). Ganoderma multiplicatum also has pale yellow margin and irregular pileipellis cells., but it differs from G. phyllanthicola by the photo brown to reddish brown pileus surface, short stipe (1.8–3 cm) and ellipsoid basidiospores (6.0–10.0 × 4.5–7.0 μm, Gottlieb and Wright 1999).

Figures

Figure 1. Maximum likelihood (ML) tree based on combined ITS + nrLSU + TEF 1 - α + RPB 2 sequence data. Bootstrap support values with a maximum likelihood (ML) equal to or greater than 60 % and Bayesian posterior probabilities (PP) equal to or greater than 0.90 are given above the nodes, shown as “ ML / PP ”. New species are indicated in bold blue.

Figure 2. Ganoderma phyllanthicola (HKAS 123776, holotype) A, B basidiomata C pore surface D cut side of pileus E, F sections of pellis G skeletal hyphae from context H binding hyphae from context I generative hyphae from tubes J – N basidiospores. Scale bars: 20 μm (G); 10 μm (E, F, H, I); 5 μm (J – N).