-- Review- - of- - the- - genus Diplazon- - Nees, -- 1819 -- (Hymenoptera: -- Ichneumonidae Diplazontinae) -- from- - Japan Author Morishita, Shunsuke Hatchodori 4 - 9, Toyohashi, Aichi 440 - 0806, Japan. Author Watanabe, Kyohei 0000-0002-8242-8611 Kanagawa Prefectural Museum of Natural History, Iryuda 499, Odawara, Kanagawa 250 - 0031, Japan. watanabe-k @ nh. kanagawa-museum. jp; https: // orcid. org / 0000 - 0002 - 8242 - 8611 watanabe-k@nh.kanagawa-museum.jp text Zootaxa 2021 2021-04-21 4964 1 103 122 journal article 7067 10.11646/zootaxa.4964.1.5 63986af4-a04f-47f6-a9db-983b7474acd1 1175-5326 4706743 ACC0503E-617A-4DC5-A967-4F2299F1A123 Diplazon pectoratorius (Thunberg, 1822) (Figs 22–27, 49, 50) Ichneumon pectoratorius Thunberg, 1822: 280 . See Yu et al . (2016) for detail. Diagnosis. Face coriaceous. Antenna with 18–20 flagellomeres in females, 19–20 in males. Mesopleuron covered with fine and dense punctures except for on and below speculum (Fig. 24). Propodeum without carinae except for posterior part of lateromedian longitudinal carina and pleural carina. Metasoma matt and dorsoventrally depressed (Figs 49, 50). Transverse impressions distinct on T I to T III (Figs 49, 50). T I 0.95–1.10 (in females) or 1.15–1.40 (in males) × as long as maximum width. T II 0.55–0.70 (in females) or 0.62–0.80 (in males) × as long as maximum width. T II and T III strongly coriaceous (Fig. 25). Face black except for a pair of spots along inner orbit yellow in females (Fig. 23), entirely yellow in males (Fig. 27). Scutellum largely orange to brown except for anterior corner and posterior part of scutellum yellow. Mesopleuron black more or less tinged with brown to orange in females (Figs 22, 24), black except for lower part of mesopleuron yellow to brownish-yellow in males (Fig. 26). Coxae orange except for apical part of fore and mid coxae yellow (Figs 22, 26). Hind tibia white with a black apex (Figs 22, 26). Metasoma entirely black. FIGURES­­22–27. Diplazon pectoratorius ( Thunberg, 1822 ) , female (22–25) and male (26, 27)―22, 26, lateral habitus; 23, 27, head, frontal view; 24, mesopleuron, lateral view; 25, T II and T III, dorsal view. Specimens­­examined . JAPAN : 1♀ , Hokkaido , Sapporo City 21. V . 1967, K. Kusigemati leg. (SEHU); 1♀ , Hokkaido , Sapporo City 29. VIII–12. IX . 1989, K. Maeto & M. Sharkey leg. (MT) (NIAES); 1♀ , Hokkaido , Ku- maishi Town , Kenichigawa , Iwafuchizawa 10–20. X. 1995 , Y. Ito & T . Ito leg. (MT) (NIAES); 1♀ , Aomori Pref. , Kizukuri Town , Hiratakinuma 29. V . 1993, T . Ichita leg. (NIAES); 1♀ , Tochigi Pref. , Kuroiso City , Higashinoma 24. X. 2001 , E. Katayama leg. ( KPMNH ) ; 1♀ , Yamanashi Pref. , Narusawa Vil. , Narusawa-Fuji path 24. IX . 2011, M. Ito leg. (KPMNH); 1♀ , Nagano Pref. , Outaki Vil. , Mt. Ontakesan , Mt. Hakkaisan 16. IX 2011, S. Fujie leg. (KPMNH); 2♀ , Aichi Pref. , Toyone Vil. , Sakauba , Kaminakamura 10. VI 2020, S. Morishita leg. (TMNH); 1♀ , Gifu Pref. , Kani City , Katabira 17–23. IV. 2004 , K. Ito leg. ( MT ) ( MU ) ; 1♀ , Toyama Pref. , Toyama City , Arimine , Jurodani 25. VIII–1. IX . 2009, M. Watanabe leg. (MT) (KPMNH); 1♂ , Aichi Pref. , Shitara , Mt. Chausuyama 27– 28. V . 1974, H. Yamada leg. (MT) (MU); 2♂ , Fukui Pref. , Ono City , Minami-Rokuroshi , Okuetsu-Kogen to Mt. Hoduki 28. V . 2011, S. Fujie leg. (KPMNH). USA : 1♀ (det. Klopfstein ), New York state , Tompkins , McLean 22. V . 1937, H. K. Townes leg. (NHRS); 1♂ (det. Klopfstein ), New York state , Mt. Slide 26. VIII. 1985 , H. & C. Townes leg. ( NHRS ) . Distribution . Japan ( Hokkaido , Honshu, and Kyushu); widely distributed in Holarctic, Neotropical and Oriental regions. Bionomics.­­ A number of hover fly species have been recorded as a host (See Yu et al . 2016 for detail), while no records are known from Japan .