Revision of the genus Woldstedtius Carlson, 1979 (Hymenoptera, Ichneumonidae, Diplazontinae) from Japan

Japanese species of the genus Woldstedtius Carlson, 1979 are revised. Nine species are recorded from Japan, including two new species, W. alpicola sp. nov. and W. punctatus sp. nov. Woldstedtius biguttatus (Gravenhorst, 1829) is newly recorded from Japan. Taxonomic status of W. flavolineatus kuroashii (Uchida, 1957) is changed from the subspecies of W. flavolineatus (Gravenhorst, 1829) to a separated species. Woldstedtius holarcticus (Diller, 1969) is newly synonymized under W. kuroashii (Uchida, 1957). A key to Japanese species of this genus is provided.