By 2000, about 70 taxa of Claviceps (Clavicipitaceae, Hypocreales) had been described, of which eight species and six varieties were described based on Japanese specimens; i.e. C. amamiensis, C. bothriochloae, C. imperatae, C. litoralis, C. microspora, C. panicoidearum, C. sorghicola, C. yanagawaensis and the varieties C. microspora var. kawatanii, C. purpurea var. agropyri, C. purpurea var. alopecuri, C. purpurea var. dactylidis, C. purpurea var. phalaridis and C. purpurea var. sasae. These Japanese Claviceps taxa, except for C. sorghicola, were based on lost specimens or had invalid names. The ambiguity of these taxa prevented taxonomic elucidation of Claviceps. To revive these taxa, which existed only in the scientific literature, it was necessary to designate neotype or epitype according to nomenclature from new specimens corresponding to these taxa. It is also desirable to provide their molecular information for advancing taxonomic studies of Claviceps. So far, fresh samples corresponding to 13 of the 14 previously described taxa were re-evaluated. As a result, neotypes were designated for C. bothriochloae, C. imperatae, C. litoralis, C. microspora and C. panicoidearum, and lecto- and epi-type were designated for C. yanagawaensis. Two varieties were elevated to species rank with designated neotypes, i.e. C. agropyri and C. kawatanii. Claviceps purpurea var. phalaridis, was elevated to species rank with designated a neotype and named C. humidiphila. Claviceps purpurea var. sasae, was redescribed as a new species C. sasae, because its original description was invalid. Claviceps purpurea var. alopecuri and var. dactylidis were synonymized with C. bavariensis.