Heteroradulum labyrinthinum (H.S. Yuan & C. Decock) L.W. Zhou comb. nov.

Basionym.

Grammatus labyrinthinus H.S. Yuan & Decock, in Yuan, Lu & Decock, MycoKeys 35: 32 (2018)

Remarks.

Heteroradulum labyrinthinum was placed in the new genus Grammatus as the generic type (Yuan et al. 2018). The main reason for introducing Grammatus was its irregularly irpicoid to poroid hymenophores, from a morphological perspective (Yuan et al. 2018). However, the morphological difference of hymenophores is not a reliable taxonomic character at the generic level within the Auriculariales . For example, Protomerulius Möller was recently shown to accommodate species with various kinds of hymenophore (Spirin et al. 2019a). This phenomenon also occurs in other groups of wood-inhabiting fungi (Wang et al. 2021). Moreover, taking the current phylogenetic evidence into consideration (Figure 1), we propose to treat Grammatus as a later synonym of Heteroradulum . Therefore, G. labyrinthinus is transferred to Heteroradulum, and Heteroradulum semis, that was moved to Grammatus (Yuan et al. 2018), is reaccepted as a member of Heteroradulum .

Species excluded from Heteroradulum