Heteroradulum Lloyd ex Spirin & Malysheva, in Malysheva & Spirin, Fungal Biology 121(8): 709 (2017)

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

Remarks.

Following the phylogenetic analysis, we treat Grammatus and Heteroradulum as a single genus, for which Heteroradulum has priority. The newly revealed Australian lineage is described as the new species Heteroradulum australiense below. In addition, G. labyrinthinus is combined to Heteroradulum and G. semis (Spirin & Malysheva) H.S. Yuan & Decock is reaccepted as a member of Heteroradulum .

Malysheva and Spirin (2017) defined the morphological characters of Heteroradulum according to the seven accepted species at that time, viz. H. adnatum, H. brasiliense (Bodman) Spirin & Malysheva, H. deglubens, H. kmetii, H. lividofuscum (Pat.) Spirin & Malysheva, H. semis and H. spinulosum (Berk. & M.A. Curtis) Spirin & Malysheva. The concept of this genus was adjusted by below including H. australiense with generative hyphae bearing a mixture of simple septa and clamp connections and H. labyrinthinus with irpicoid to poroid hymenophores.