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Page number:101 
Remarks (internal):Thanatephorus theobromae is only known from the hoIotype specimen, but is distinct because of its large basidiospores. The species was placed in Oncobasidium 'largely on basidial morphology' (Talbot & Keane, 1971), the genus being characterized by 'capitate-clavate' basidia with comparatively short sterigmata. These features are not considered distinct, and a transfer to Thanatephorus is here proposed, based on the vertically branching, cymose, sub-basidial hyphae. 
Description type:Non-original description 
Description:Thanatephorus theobromae (P.H.B. Talbot & Keane) P. Roberts comb. nov. Figure 55
Oncobasidium theobromae F.H.B. Talbot & Keane, Austral. Journal Bot. 19: 203 (1971).
Teleomorph. Basidiome: effused, thin, 'subhypochnoid' (Talbot & Keane, 1971), smooth, white. Hymenium: comprising one or more layers of basidia on vertically branching, cymose, thin-walled hyphae arising from a subicular layer of wider, thick-walled, basal hyphae. Hyphae: binucleate, subhymenial hyphae thin-walled, hyaline, with short hyphal compartments, somewhat swollen, 5-6 µm diam.; basal hyphae hyaline to yellowish, with long hyphal compartments, straight, up to 10 µm diam., thin-walled. Clamp connexions absent. Basidia: ellipsoid to oblong or cylindrical (Q = 1.3-2.7), 15-30 x (10-)12-16 µm. Sterigmata: four, 6-12.5 x 3-4 µm. Basidiospores: ellipsoid (Q = 2.0-2.4), 13.5-18.5 x 6.5-9 µm ((12-)15-25 x (5-)6.5-8.5 µm fide Talbot & Keane, 1971), hyaline, thin-walled, producing secondary spores by replication.
Anamorph. No anamorph known. Sclerotia said to be absent (Talbot & Keane, 1971).
Habitat and ecology. Known only from leaves and stems of cocoa (Theobroma cacao). Apparently parasitic.
Distribution. Papua New Guinea. Known only from the type specimen.
Type specimen. Papua New Guinea: New Britain, Keravat, on Theobroma cacao, 1970, P.J. Keane, ADW 1622, holotype (!).
Additional illustration. Talbot & Keane (1971).
Taxon name: