Villosiclava virens gen. nov., comb. nov., teleomorph of Ustilaginoidea virens, the causal agent of rice false smut

False smut is a serious worldwide rice disease.The anamorphic state of the causal fungus is Ustilaginoidea virens.The teleomorphic state was introduced in 1934 and was allied with the family Clavicipitaceae.At present Claviceps virens is applied as the teleomorph name of this fungus.However, morphological and biological characteristics of the teleomorph are distinct from those of the genus Claviceps.In particular, the Ustilaginoidea anamorph differs from the Sphacelia anamorph that characterises the genus Claviceps.We deliberated on the nomenclature of rice false smut fungus, compared the fungus with Claviceps, and found it is not appropriate to any existing clavicipitaceous genera.In this paper, a new genus Villosiclava, a new combination V. virens and an emended description for the teleomorph of rice false smut fungus are proposed.In the absence of the original specimen, an epitype is also designated.