Taxonomic and Zoogeographic Study of the Japanese Phygadeuontinae (Hymenoptera, Ichneumonidae), with Descriptions of 17 New Species Author Watanabe, Kyohei Kanagawa Prefectural Museum of Natural History, 499 Iryuda, Odawara, Kanagawa 250 – 0031, Japan watanabe-k@nh‛kanagawa-museum‛jp text Bulletin of the Kanagawa Prefectural Museum (Natural Science) 2021 2021-03-30 50 55 136 https://doi.org/10.32225/bkpmnh.2021.50_55 journal article 300009 10.32225/bkpmnh.2021.50_55 70224806-ca38-47ca-bd8a-63da3ac532f9 2189-6720 12774639 DD695C62-DC2F-4D32-8D33-52648E28661D Genus Mastrus Förster, 1869 Mastrus Förster, 1869: 176 . Type : Phygadeuon ( Mastrus ) neodiprioni Viereck, 1911 . Included by Viereck (1911) . Daictes Förster, 1869: 176 . Type : Phygadeuon ( Daictes ) fukaii Viereck, 1911 . Included by Viereck (1911) . A e n o p l e x F ö r s t e r, 1 8 6 9: 1 7 6. Ty p e: A e n o p l e x betulaecola Ashmead, 1896 (= Orthocentrus pilifrons Provancher, 1879 ). Included by Ashmead (1896) . Seven species, Ma. ecornutus Momoi, 1970 , Ma. fukaii ( Viereck 1911 ) , Ma. molestae (Uchida, 1933) , Ma. oshimensis ( Uchida, 1930 ) , Ma. sugiharai (Uchida, 1936) , Ma. takadai Momoi, 1970 , and Ma. tenuibasalis ( Uchida, 1940 ) , have been recorded from Japan . I found more than ten undetermined species from Japan . The taxonomic treatment of these species requires the additional specimens and comparison with European species. In this study, I re-describe Ma. molestae and record some distributional data of this species and Ma. takadai below.