Amphirhachis miyabi, Watanabe, Kyohei, 2017

Watanabe, Kyohei, 2017, Revision of the genus Amphirhachis Townes, 1970 (Hymenoptera, Ichneumonidae, Banchinae) from Japan, ZooKeys 685, pp. 49-64 : 53-55

Amphirhachis miyabi sp. n. Figs 7-9

Diagnosis.

Clypeus 0.4 times as long as wide. Face 0.5 times as long as wide, with a narrow longitudinal depression between eye and antennal socket. Antenna with 46-49 flagellomeres. Hind femur 6.4-6.9 times as long as maximum depth in lateral view, black or reddish brown. T1 1.9-2.0 times as long as maximum width. Base of T1 without yellow area or spots. T2 0.9-1.0 times as long as maximum width. Each metasomal tergite with a posterior white band. Ovipositor sheath 0.4-0.5 times as long as hind tibia.

Description.

Female (n = 18). Body length 10.0-11.0 (HT: 10.0) mm.

Head 0.6 times as long as wide. Clypeus 0.4 times as long as wide. Face slightly convex medially, 0.5 times as long as wide, with a narrow longitudinal depression between eye and antennal socket (Fig. 8). Frons with a longitudinal area before anterior ocellus without punctures. POL 0.8-1.0 (HT: 0.8) times as long as OOL. MSL 0.7-0.8 (HT: 0.7) times as long as BWM. Antenna with 46-49 (HT: 46) flagellomeres. F1 1.6-1.7 (HT: 1.6) times as long as F2.

Mesosoma. Mesopleuron with a very small speculum. Pleural carina present but trace-like in entire length. Fore wing length 9.0-10.0 (HT: 9.0) mm. Hind femur 6.4-6.9 (HT: 6.9) times as long as maximum depth in lateral view. Hind TS1 2.0-2.1 (HT: 2.1) times as long as TS2.

Metasoma. T1 1.9-2.0 (HT: 1.9) times as long as maximum width. T2 0.9-1.0 (HT: 0.9) times as long as maximum width. Ovipositor sheath 0.4-0.5 (HT: 0.5) times as long as hind tibia.

Colouration (Figs 7-9). Body (excluding wings and legs) black, except for: clypeus excluding dorsal part, vertex with a pair of spots between lateral ocellus and eye, mandible excluding apex and base, a median band of flagellum, anterolateral spots of mesoscutum, subalar prominence, apical spots of T1, apical transverse stripe of T2-T7 white to whitish yellow; palpi brown; metasomal sternites blackish brown brown basally, whitish brown apically. Wings hyaline; veins and pterostigma blackish brown to brown except for yellow wing base. Coxae, trochanters and trochantelli black. Fore and mid femora, tibiae and tarsi reddish brown to brown. Hind femur, base and apical part of hind tibia, basal 0.7-0.8 (HT: 0.8) of hind TS1, and TS5 black to blackish brown. Subbasal area of hind tibia reddish brown. Apical 0.2 of hind TS1 and TS2-TS4 whitish yellow. In some paratypes with: collar with yellow spot medially, mesoscutum with a indistinct, median yellow spot, scutellum with a pair of small yellow spots, and propodeum with a pair of small yellow spots near the socket of hind coxa. The apical yellow spot of T1 usually united into a single transverse stripe. In specimens collected in Yakushima Is., hind femur sometimes tinged with reddish brown. Ovipositor reddish brown.

Male. Unknown.

Specimens examined.

JAPAN: [Holotype] F, Nagasaki Pref., Tsushima Is., Kamitsushima Town, Izumi, Shitazaki (ca. 10 m alt.), 8. V. 2015, T. Kurihara leg. (KPMNH). [Paratypes] 2 F, Aichi Pref., Nagoya City, Higashiyama Park, 1-10. V. 2001, M. Watanabe leg. (MsT) (MU); 2 F, same locality and collector, 11-20. V. 2001 (MsT) (MU); 5 F, Aichi Pref., Toyota City, Takiwaki, 30. IV. - 6. V. 2002, Y. Kurahashi leg. (MsT) (MU); 2 F, Aichi Pref., Toyota City, Sanage, 30. IV. - 6. V. 2002, M. Kiyota leg. (MsT) (MU); 1 F, Miyazaki Pref., Mt. Wanizuka, 23. V. 1966, K. Kusigemati leg. (SEHU); 1 F, Kagoshima Pref., Yakushima Is., Kosugidani, 2. VI. 1969, K. Kusigemati leg. (SEHU); 1 F, same locality and collector, 3. VI. 1969 (SEHU); 3 F, Kagoshima Pref., Yakushima Is., Shiratani (600 m alt.), 6. V. - 20. VI. 2000, T. Murata leg. (MsT) (MU).

Distribution.

Japan (Honshu, Kyushu, Tsushima Is. and Yakushima Is.),

Etymology.

The specific name is from a Japanese term “Miyabi”, which means elegant.

Bionomics.

Host is unknown.

Remarks.

This species resembles A. fujiei sp. n. in the body structures, but it can be distinguished by ovipositor sheath 0.4-0.5 times as long as hind tibia (0.3 times in A. fujiei sp. n.) and the each metasomal tergite with a posterior white band (entirely black in female of A. fujiei sp. n.).