Megastylus (Dicolus) excubitor ( Förster, 1871 )

Watanabe, Kyohei, 2023, Taxonomic and Zoogeographic Notes on Japanese Orthocentrinae (Hymenoptera, Ichneumonidae), with Descriptions of Four New Species, Bulletin of the Kanagawa Prefectural Museum (Natural Science) 52, pp. 7-44 : 26

Megastylus (Dicolus) excubitor ( Förster, 1871)

[New SJN: Okushi-ashinaga-hae-himebachi]

( Figs. 12A–C, 23G, H)

Dicolus excubitor Förster, 1871: 97 .

Diagnosis. Fore TS I longer than half length of fore tibia ( Fig. 23G). Antennal cleaner of fore TS I large, causing conspicuous outcurving of base of TS I ( Figs. 23G, H). Inner eye orbit almost parallel ( Fig. 12B). Propodeum without anterior transverse carina. Hind tibia not distinctly narrowed in apical 1/3 ( Fig. 12A). T I and T II without longitudinal striae. In female: fore wing length 4.5–6.0 mm. FL I 6.0–8.5 times as long as maximum depth in lateral view. In male: T I 3.5 times as long as maximum width; FL I shorter than 7.6 times as long as maximum depth in lateral view; mesopleuron and scutellum sometimes yellow.

Material examined. JAPAN: KPM-NK 89786 , F, Yamagata Pref., Nishikawa T., Shizu, Mt. Gassan , 19. VI. 2015, K. Watanabe leg. ; KPM-NK 89787 , F, Yamanashi Pref., Koushu City, Sagashio , 6. VIII. 2008, K. Watanabe leg. ; KPM-NK 89788 , F, Nagano Pref., Outaki Vil., Mt. Ontake-san, Hakkaisan , 8. VIII. 2010, K. Watanabe leg. ; OMNH, F, Nagano Pref., Hara Vil. , 5. IX. 2015, M. Ito leg. ; KPM-NK 89789 , F, Toyama Pref., Toga Vil., Kamimomose , 15–29. IX. 2009, M. Watanabe leg. (MsT) ; KPM-NK 89790 , F, Kagoshima Pref., Yakushima Is., Kankake, 1. V. – 5. VI. 2007 , T. Yamauchi et al. leg. (MsT); KPM-NK 89791 , F, Kagoshima Pref., Yakushima Is., Hanyama, 2. XI. – 1. XII. 2007 , T. Yamauchi et al. leg. (MsT). RUSSIA: ZISP, F (det. Rossem), Crimea, Frunzenskoye , 1. VII. 1978, D. R. Kasparyan leg.

Distribution. Japan (Honshu and Yakushima Is.); widely distributed in Palaearctic region ( Yu et al., 2016).

Remarks. This is the first record of this species from Japan.