Amphirhachis nigra Townes, 1970

Watanabe, Kyohei, 2017, Revision of the genus Amphirhachis Townes, 1970 (Hymenoptera, Ichneumonidae, Banchinae) from Japan, ZooKeys 685, pp. 49-64 : 55-56

Amphirhachis nigra Townes, 1970 Figs 10-12, 13-15

Amphirhachis nigra Townes, 1970: 33.

Description.

Female (n = 32). Body length 10.0-12.5 mm.

Head 0.6 times as long as wide. Clypeus 0.5 times as long as wide. Face slightly convex medially, 0.6 times as long as wide, without a narrow longitudinal depression between eye and antennal socket (Fig. 11). Frons densely punctate with rugae above each antennal socket, without a longitudinal area before anterior ocellus without punctures. POL 0.8-1.0 times as long as OOL. MSL 0.7 times as long as BWM. Antenna with 56-57 flagellomeres. F1 1.5-1.6 times as long as F2.

Mesosoma. Mesopleuron without a speculum. Pleural carina present but trace-like in entire length. Fore wing length 9.0-12.5 mm. Hind femur 7.1-8.1 times as long as maximum depth in lateral view. Hind TS1 1.9-2.0 times as long as TS2.

Metasoma. T1 2.2-2.8 (usually 2.2-2.3) times as long as maximum width. T2 1.1-1.3 times as long as maximum width. Ovipositor sheath 0.3-0.4 (usually 0.3) times as long as hind tibia.

Colouration (Figs 10-12). Body (excluding wings and legs) black, except for: clypeus except for dorsal part, longitudinal stripes along orbit except for ventral part of face and dorsal part of gena, mandible excluding apex and base, a median band of flagellum, a pair of median spot of collar, a pair of small spot of scutellum, anterolateral small spots of T1, posterior transverse stripe of T2, narrow posterior margin of T3-T6, base and apex of S1, posterior transverse stripe of S2-S6 whitish yellow; palpi, ventral surface of scape and pedicel, posterodorsal corner of pronotum, subalar prominence, and dorsal area of mesepimeron tinged with brown to reddish brown. The marking along orbit sometimes partly reduced. Scutellum sometimes without yellow markings. Stripes of metasomal tergites sometimes reduced but usually present on T2. Wings hyaline; veins and pterostigma blackish brown to brown except for yellow wing base. Legs black except for: fore and mid femora, tibiae and tarsi partly blackish brown to reddish brown and hind TS2-TS4 white to whitish yellow. Hind femur and tibia sometimes tinged with reddish brown. Hind TS2 sometimes black basally.

Male (n = 24). In body structure, similar to female except for: MSL 0.4-0.6 times as long as BWM, antenna with 54-58 flagellomeres, F1 1.4-1.6 times as long as F2, anterior part of pleural carina well-developed, T1 relatively longer than female (usually 2.5-2.6 times as long as maximum width), hind femur 6.5-7.7 times as long as maximum depth in lateral view, hind TS1 1.8-1.9 times as long as TS2 and T2 1.4-1.8 times as long as maximum width. In colouration, similar to the pattern of female but largely differed (Figs 13-15). Clypeus and malar space entirely yellow. Face yellow except for median longitudinal black stripe. Palpi, ventral spot of scape and pedicel, and median band of flagellum whitish yellow to yellow. Collar, posterodorsal corner of pronotum, anterolateral spots of mesoscutum, subalar prominence, dorsal area of mesepimeron and posterior transverse stripe of T1-T7 whitish yellow to yellow. Propleuron sometimes with a whitish yellow to yellow spot. Mesoscutum sometimes with a median yellow spot. Mesopleuron usually along mesosternum with a longitudinal whitish yellow stripe. Mesepimeron sometimes entirely whitish yellow. Propodeum sometimes with a pair of small yellow spots near the socket of hind coxa. Fore and mid legs whitish yellow to reddish yellow. Hind coxa partly tinged with whitish yellow. Hind trochanter and trochantellus whitish yellow. Hind femur, tibia and tarsus more or less paler than female especially basal part of tibia largely reddish brown.

Specimens examined.

JAPAN: 1 M, Hokkaido, Mt. Tarumae-san, 12-21. VII. 1998, K. Konishi leg. (MsT.) (NIAES); 1 F, same locality and collector, 21-26. VII. 1998 (MsT) (NIAES); 8 M, Hokkaido, Sapporo City, Mt. Soranuma-dake, 14. VI. - 4. VII. 2007, A. Ueda leg. (MsT) (KPMNH); 1 F, same locality and collector, 27. VII. - 21. VIII. 2007 (MsT) (KPMNH); 2 M, Hokkaido, Hidaka Town, Uenzaru-gawa, 21. VI. - 10. VII. 2007, A. Ueda leg. (MsT) (KPMNH); 1 M, same locality and collector, 10. VII. - 1. VIII. 2007 (MsT) (KPMNH); 1 M, Hokkaido, Eniwa City, Izari, Ichankoppe-zawa, 20-30. VI. 1995, T. Ito leg. (MsT) (NIAES); 1 M, same locality and collector, 12-20. VII. 1995 (MsT) (NIAES); 1 F, same locality and collector, 21-31. VII. 1995 (MsT) (NIAES); 1 M, Kanagawa Pref., Atsugi City, Mt. Oyama (1250 m alt.), 7. VI. 1997, M. Kato leg. (KPMNH); 1 F, Kanagawa Pref., Mt. Tanzawa-san, 16. V. 2013, T. Taniwaki leg. (FIT) (KPMNH); 1 M, same locality and collector, 20. VI. 2013 (FIT) (KPMNH); 1 M, Kanagawa Pref., Mt. Oomuro-yama, 16. VI. 2013, T. Taniwaki leg. (FIT) (KPMNH); 2 M, Kanagawa Pref., Mt. Hinokiboramaru, 23. V. 2013, T. Taniwaki leg. (FIT) (KPMNH); 2 M, Kanagawa Pref., Mt. Hinokiboramaru, 6. VI. 2013, T. Taniwaki leg. (FIT) (KPMNH); 1 F, Shizuoka Pref., Kanaya City, Fukuyo, 16. XI. 1952, J. Minamikawa leg. (NIAES); 1 F, Shizuoka Pref., Kanaya, 1. XII. 1955, J. Minamikawa leg. (NIAES); 1 F (holotype), Nagano Pref., Kamikochi, 31. VII. 1954, Townes family leg. (AEIC); 1 F, Nagano Pref., Mt. Shiroumayari, 29. VII. 1972, T. Aoki leg. (NIAES); 1 F, Nagano Pref., Outaki Vil., Mt. Ontake-san, Hakkaisan, 16. IX. 2011, S. Fujie leg. (KPMNH); 1 M, same locality, 8-9. VIII. 2014, S. Shimizu leg. (MsT.) (KPMNH); 1 M, Ishikawa Pref., Mt. Hakusan, 5. VIII. 1993, I. Togashi leg. (NIAES); 1 M, same locality and collector, 8. IX. 1996 (NIAES); 1 F, Mie Pref., Owase, 16. XI. 1958, S. Ishida leg. (NIAES); 1 F, “Odaigahara”, 6. VI. 2004, A. Kawazoe leg. (KPMNH); 1 F, Nara Pref., Odaigahara (1500 m alt.), 25. VI. 1984, K. Konishi leg. (NIAES); 1 F, Ehime Pref., Odamiyama, 15. VI. 1990, E. Yamamoto leg. (NIAES); 1 F, same locality and collector, 13. V. 1994 (NIAES); 1 F, same locality and collector, 27. V. 1994 (NIAES); 1 F, same locality and collector, 28. V. 1994 (NIAES); 1 F, same locality and collector, 26. VI. 1994 (NIAES); 2 F, same locality and collector, 1. VI. 1995 (NIAES); 1 F, same locality and collector, 5. VI. 1995 (NIAES); 1 F, same locality and collector, 11. VI. 1995 (NIAES); 2 F, same locality and collector, 25. VI. 1995 (NIAES); 1 F, same locality and collector, 10. VII. 1995 (NIAES); 1 F, Tokushima Pref., Mt. Tsurugisan, 19. VI. 1981, I. Kanazawa leg. (LT) (NIAES); 2 F, Kumamoto Pref., Mt. Aso, 12. VI. 1978, H. Makihara leg. (LT) (NIAES); same locality and collector, 18. VI. 1978 (LT) (NIAES); 1 F, Kumamoto Pref., Izumi Vil., Mt. Shiratori-yama (1300 m alt.), 6. VI. 1980, K. Ohara leg. (NIAES); 1 F, Kumamoto Pref., Izumi Vil., "Mt. Hakuchō-zan” (= Mt. Shiratori-yama ??), 14. V. 1983, K. Ohara leg. (NIAES); 1 F, same locality, 14-21. V. 1983, K. Ohara & T. Goto leg. (MsT) (NIAES); 1 F, Kumamoto Pref., Shiiya-toge (1400 m alt.), 15. VI. 1985, K. Konishi et al. leg. (LT) (NIAES).

Distribution.

Japan (Hokkaido, Honshu, Shikoku and Kyushu); Far East Russia.

Bionomics.

Host is unknown. Some specimens collected from Shikoku and Kyushu were collected by light trap.

Remarks.

This is the first record of the male. Males were collected only from Hokkaido and Honshu.