Diplazon neoalpinus Zwakhals, 1979

Morishita, Shunsuke & Watanabe, Kyohei, 2021, -- Review- - of- - the- - genus Diplazon- - Nees, -- 1819 -- (Hymenoptera: -- Ichneumonidae Diplazontinae) -- from- - Japan, Zootaxa 4964 (1), pp. 103-122 : 108-109

Diplazon neoalpinus Zwakhals, 1979

(Figs 11–16, 47, 48)

Bassus alpinus Holmgren 1858: 361 . Name preoccupied.

Diplazon neoalpinus Zwakhals, 1979: 74 . New name.

Diagnosis.­­ Face coriaceous. Antenna with 17–18 (in females) or 17–20 (in males) flagellomeres. Mesopleuron covered with fine and dense punctures except for on and below speculum (Fig. 13). Propodeum without carinae except for posterior part of lateral longitudinal carina and pleural carina. Metasoma matt, posterior part of T III to apex of metasoma strongly compressed in females (Fig. 47), weakly compressed in males (Fig. 48). Transverse impressions distinct on T I and TII (Figs 47, 48). T I 1.00–1.20 (in females) or 1.24–1.55 (in males) × as long as maximum width. T II 0.70–1.00 (in females) or 0.85–1.00 (in males) × as long as maximum width. T II and T III strongly coriaceous (Fig. 14). Face black except for a pair of spots along inner orbit yellow in females (Fig. 12), entirely yellow in males (Fig. 16). Scutellum black or orange except for anterior corner and posterior part of scutellum yellow. Mesopleuron entirely black in females (Figs 11, 13), black except for lower part of mesopleuron yellow in males (Fig. 15). Coxae yellow except for hind coxae orange to brown (Figs 11, 15). Hind tibia black with white base (Fig. 11). Metasoma entirely black.

Specimens­­examined. JAPAN: 1♀, Hokkaido, Otaru City, Mt. Kenashiyama 29–31. V . 2002, A. Yamamoto leg. (KPMNH); 1♀, Hokkaido, Sapporo City 4. VI . 1969, H. Takizawa leg. (SEHU); 1♀, Tochigi Pref., Nasushio- bara City, Shiobara, Utouzawa 22–28. V . 2008, T . Matsumura leg. (MT) (KPMNH); 2♀, Aichi Pref., Toyone Vil., Sakauba, Kaminakamura 10. VI . 2020, S. Morishita leg. (TMNH); 1♀, Nagano Pref., Outaki Vil., Mt. Ontakesan 25. VI –15. VII. 2015, S. Shimizu leg. (MT) (KPMNH); 1♀, ditto, 8–9. VIII. 2014 ( KPMNH) ; 1♀, Fukui Pref., Ike- da town, Mt. Hekosan 11. VI . 2016, S. Shimizu leg. (KPMNH); 1♂, Tokyo, Ome City, Mt. Mitakesan 1. VI . 2008, M. Gunji leg. (KPMNH); 1♂, Kanagawa Pref., Yamakita Town, Mt. Hinokiboramaru 16. V . 2013, T . Taniwaki leg. (FIT) (KPMNH); 2♂, Kumamoto Pref., Gokanosho, Mt. Hakuchosan 13. V . 1980, N. Koda leg. (SEHU).

Distribution. Japan (Shikotan Is., Hokkaido, Honshu, and Kyushu); widely distributed in Palearctic region.

Bionomics. Unknown.

Remarks.­­ This is the first record of this species from Hokkaido and Kyushu. This species resembles D. pectoratorius in that both species have mesopleuron with fine and dense punctures except for on and below speculum, hind tibia black with white base, and metasoma with strongly coriaceous sculpturing, but it can be distinguished by the compressed tergites (depressed in D. pectoratorius ) and the transverse impressions absent on T III (present on T III in D. pectoratorius ).