Ceratobasidiaceae

Taxonomy

The family was created in 1948 by American mycologist G.W. Martin to accommodate species of corticioid fungi with heterobasidiomycete features (elongated sterigmata and basidiospores that give rise to secondary spores). He restricted the Ceratobasidiaceae to the genus Ceratobasidium, though including within the genus species later placed in Thanatephorus and Oliveonia. In 1981, Jülich created the order Ceratobasidiales to accommodate the family. By 1995, the order and the family contained 18 genera, including Ceratobasidium, Heteroacanthella, Oliveonia, Scotomyces, Thanatephorus, and their various synonyms and anamorphs.

Current status

Molecular research, based on cladistic analysis of DNA sequences, has now shown that the Ceratobasidiaceae do not belong to a separate order, but are part of the Cantharellales. The genera Heteroacanthella and Oliveonia are not closely related to the Ceratobasidiaceae, but have been placed in the Auriculariales. No species of the genus Scotomyces has yet been sequenced.

Following changes to the International Code of Nomenclature for algae, fungi, and plants, the practice of giving different names to teleomorph and anamorph forms of the same fungus was discontinued, meaning that Thanatephorus became a synonym of the earlier name Rhizoctonia, previously used for anamorphic species. DNA evidence also placed most, if not all, Ceratobasidium species in Rhizoctonia.

Research on the septal pore ultrastructure of the little-known and atypical type species of Ceratobasidium, C. calosporum, indicates that it is a member of the Auriculariales and is unrelated to other species of Ceratobasidium. Technically, this means that the Ceratobasidiaceae belong within the Auriculariales, but this is a taxonomic problem that has yet to be resolved.