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Remarks (internal):Rhizoctonia ramicola (30) and Pellicularia koleroga have been recorded on Pittosporum sp. (17. 30). µm koleroga was created by Cooke in 1876 as the type species of Pellicularia (26). In 1943, Rogers (17) combined Corticium koleroga. C. stevensii, and C. ochroleucum under µm koleroga. Corticium stevensii was created by hurt (2) in 1918 and was a synonym of C. ochroleucum (29). Rogers (17) and Wolf and Bach (31) considered that C. koleroga and C. stevensii were identical. Talbot (26) supported hurt (2) and claimed that these two species were distinct. In 1955, Donk (5) rejected Pellicularia and µm koleroga, as nomina confusa, and proposed the new genus and new species, Koleroga noria for the retypified mixed specimen. Recently, K. noxia was proved a species of Ceratobasidium. Koleroga. therefore, should be reduced to synonymy with Ceratobasidium (26). Venkatarayan (28) transferred µm koleroga to Ceratobasidium in 1949.
The imperfect stage of R. ramicola differs from C. stevensii by the absence of sclerotia. it resembles K. noxia (=C. koleroga), but its basidiospores are smaller and more globose than those of K. noxia. Records of R. ramicola. (30) and µm koleroga (17) on the leaves of Pittosporum seem to refer to the same fungus in different stages. This fungus is related to Corticium koleroga (Cooke) Höhn. and C. stevensii Burt (3, 17, 31), but C.stevensii produces sclerotia and forms thicker, and dark-colored fructifications (3). Rhizoctonia ramicola, which lacks sclerotia (30), is more closely related to C. koleroga (3) than to
C. stevensii.
The features mentioned above, together with the binucleate hyphal cells, show that Rhizoctonia ramicola belongs to the genus Ceratobasidium, (18, 26), and is designated here as a new species.
 
Description:Ceratobasidium ramicola Tu, Roberts & Kimbrough, sp. nov. Hypobasidia simplicia, ovoidea, 8.0-(11.1)-15.6 x 5.2-(7.8)-10.8 µm, cum 4 epibasidiis, quoe props tom longs quoit hypobasidia sunt: inter epibasidia et hypobasidia septa aliquando formata sunt: basidiosporae laeves, hyaline, repetentes, non amyloideae, 5.2-(8.5)-10.5 x 3.5-(5.2)-6.9 µm ; in Pittospori fouis repertae sunt, DeLand, Florida, U S A.
Basidia simple, ovoid, 8.0-(11.1)-15.6 x 5.2- (7.8) -10.8 µm. Epibasidia usually in number, approximately the same length as hypobasidia. Basidiospores smooth, hyaline, repetitive, not amyloid, 5.2(8.5)-10.5 x 3.5-(5.2)-69 µm. Transverse septa occasionally formed between epibasidia and hypobasidia. Habitat: foliage of Pittosporum tobira Ait. in Del .and, Florida, U. S. A.
The type specimen has been deposited in the University of Florida Herbarium as No. FLAS F47538.

 
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