Xylodon nongravis (Lloyd) C.C. Chen & Sheng H. Wu, in Chen et al. 2018: 349

Viner, Ilya, Spirin, Viacheslav, Zibarova, Lucie & Larsson, Karl-Henrik, 2018, Additions to the taxonomy of Lagarobasidium and Xylodon (Hymenochaetales, Basidiomycota), MycoKeys 41, pp. 65-90 : 75-77

Xylodon nongravis (Lloyd) C.C. Chen & Sheng H. Wu, in Chen et al. 2018: 349 Figure 9

Basionym.

Polyporus nongravis Lloyd, Mycol. Writings 6 (61): 891. 1919.

Type.

Sri Lanka. Peradeniya, on rotten branch, T.Petch (holotype BPI [305211]).

Wu (2000) re-described and illustrated this poroid species as Hyphodontia nongravis (Lloyd) S.H. Wu. Our specimens collected in the Russian Far East fit well with his description. One of these collections (Spirin 5763) was sequenced and proved to be close to other sequences of H. nongravis available in GenBank. The species undoubtedly belongs to the core Xylodon clade (Figure 1) where it has been combined by Chen et al. (2018). However, the type specimen of Polyporus nongravis possesses small but clear morphological differences from our collections: in particular, wider pores (2-3 per mm in the type, 3-4 per mm in East Asian specimens) and broader tramal hyphae (4-6 μm vs. 3-4.5 μm in diam.), as well as broader, predominantly subglobose basidiospores, 3.9 –4.7×3.6– 4.2 μm (n=30/1), L=4.27, W=3.97, Q=1.08 (vs ovoid-ellipsoid, 4.0 –5.2×3.0– 4.1 μm (n=60/2), L=4.74, W=3.46, Q=1.38 in East Asian specimens). An epitype for P. nongravis from the locus classicus is needed to re-introduce this species based on modern methods and to clarify the taxonomic status of X. nongravis sensu East Asia.