Rhizoctonia papillata (Warcup & P.H.B. Talbot) R.P. O’Donnell, C.C. Linde & T.W. May, comb. nov. MB 852072. Basionym: C eratobasidium papillatum Warcup & P.H.B. Talbot, New Phytol. 86 (3): 268. 1980. Type citation. ‘ Holotypus: Herb. ADW No. 16596, J. H. Warcup (0808)... Hosts: Sarcochilus dilatatus F. Muell., Toowoomba, Queensland (isolate 0808) ’. ITS barcode: AJ427401 (T). UNITE 1.5 % SH: n/a. Alternative markers: LSU = KF267084 (T); RPB2 = DQ301724 (T). Ex-type culture: CBS 570.83. Notes: Roberts (1999) considered Cb. papillatum as synonymous with Cb. cornigerum and stated that the type specimen was lost. However, an ex-type culture (CBS 570.83) is extant, and corresponds with Warcup’s original isolate number (0808). Sequences from this ex-type culture used in our analyses place Cb. papillatum in a different clade altogether to Cb. cornigerum and R. ramicola which it was previously considered synonymous with. Ceratobasidium papillatum is therefore treated here as a distinct species and transferred to Rhizoctonia. A sequence for the ATP6 mitochondrial region from the ex-type culture of Cb. papillatum (CBS 570.83) has been deposited in GenBank (DQ301593); however, when BLASTed, the only result returned is a single accession matching the original search query (i.e. itself). Additionally, this sequence was unable to be aligned confidently with any other ATP6 sequences retrieved here. This sequence appears to be an aberration that cannot be matched with any other existing ATP6 sequence on GenBank, and it is unlikely that it is representative of this taxon. For these reasons, we have excluded it from our analyses here and do not include it among sequenced markers listed above.

Published as part of 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), pp. 285-325 in Persoonia 54 (1) on page 310, DOI: 10.3114/persoonia.2025.54.09, http://zenodo.org/record/17127619