Rhizoctonia floccosa Burgeff, Saprophyt. Symb.

O’Donnell, R. P., Linde, C. C. & May, T. W., 2025, Rise up, Rhizoctonia: moving to one fungus, one name in the Ceratobasidiaceae (Agaricomycetes, Cantharellales), Persoonia 54 (1), pp. 285-325 : 303

publication ID	https://doi.org/10.3114/persoonia.2025.54.09
DOI	https://doi.org/10.5281/zenodo.16877661
persistent identifier	https://treatment.plazi.org/id/03A69C14-FF8F-FF8F-FCAD-FF2F62D94C4A
treatment provided by	Felipe
scientific name	Rhizoctonia floccosa Burgeff, Saprophyt. Symb.
status

Treatment

Rhizoctonia floccosa Burgeff, Saprophyt. Symb. View in CoL : 152. 1932.

Type citation: ‘ M. R. [Mycelium radicis] (Myrmechis) glabrae (Pangerango, Java)... M. R. (Myrmechis) gracilis (Pangerango, Java).’

ITS barcode: MH855816 View Materials ( R).

UNITE 1.5 % SH: SH0987472.10FU.

Alternative marker: LSU = MH867319 View Materials (R).

Authentic strain culture: CBS 336.36.

Notes: Considered a nomen dubium by Andersen & Stalpers (1994) and Roberts (1999), as no holotype specimen was designated. However, an authentic strain (CBS 336.36) isolated by Burgeff from the host orchid ( Myrmechis glabrae ) mentioned in the protologue and collected from the type locality (‘Tjibodas’[Cibodas], ‘Pangerango’[Pangrango]) is extant and has been sequenced. In the present study, phylogenetic analysis recovered this representative sequence as separate from sequences from named Rhizoctonia species but closely related to unnamed orchid mycorrhizal OTUs. Andersen & Stalpers (1994) note in their discussion of R. floccosa that “the very small monilioid cells are quite distinct” (p. 442). This morphological distinction, coupled with molecular results in this study suggest that recognition of R. floccosa at the species level is indeed warranted.