Stilbops montanus, Watanabe, Kyohei & Maeto, Kaoru, 2012

Watanabe, Kyohei & Maeto, Kaoru, 2012, Taxonomic study of the genus Stilbops Förster from Japan (Hymenoptera: Ichneumonidae: Stilbopinae), Zootaxa 3456, pp. 51-81 : 76-77

publication ID	https://doi.org/ 10.5281/zenodo.211080
DOI	https://doi.org/10.5281/zenodo.6178666
persistent identifier	https://treatment.plazi.org/id/8079878D-FFB0-FF8E-4DAD-6CF7FAD073A8
treatment provided by	Plazi
scientific name	Stilbops montanus
status	sp. nov.

Treatment

Stilbops montanus sp. nov.

( Figs. 2 View FIGURE 2 I, 3 I, 4 I, 5 I, M, 6 I, 7 I, 8 I, 9 J, 10 I, 11 I, J, 12 M, N, 13, 14 C)

Diagnosis. Lower part of gena with concavity in lateral view ( Fig. 3 View FIGURE 3 I); hind tibia 7.8–8.5 times as long as deep in lateral view; Cu-a distant from Rs&M by 0.6–0.8 times length of Cu-a; TI 1.3–1.4 (in female) or 1.4–1.6 (in male) times as long as maximum width; TII and TIII without weak round convexities; ovipositor upcurved in posterior half. Tegula, hind coxa, femur, tibia and tarsus almost black (or blackish-brown); TII and following tergites usually reddish-brown.

Description. Female (n= 17). Body length 4.4–5.3 (HT: 5.2) mm; length of fore wing 3.8–4.5 (HT: 4.0) mm.

Head 0.5–0.6 (HT: 0.6) times as long as wide; clypeus 0.6–0.7 (HT: 0.6) times as long as wide, narrowly punctate dorsally, lower half sometimes shagreened, its margin convex in anterior view ( Fig. 2 View FIGURE 2 I); anterior tentorial pit small ( Fig. 2 View FIGURE 2 I), its margin not concealed by setae; face 0.7 times as long as wide, punctures on center part obliquely elongated; frons covered with punctures as face, area above antennal socket transversely striated, and with narrow longitudinal ridge medially; OOL 1.4–1.6 (HT: 1.6) times as long as OD; POL 1.2–1.5 (HT: 1.4) times as long as OD; lower end of occipital carina effaced ( Fig. 4 View FIGURE 4 I); GOI 0.5–0.6 (HT: 0.6); lower part of gena with concavity in lateral view ( Fig. 3 View FIGURE 3 I); malar space 1.0 times as long as basal width of mandible; mandibular base flat. Antenna with 17 or 18 flagellomeres; flagellomere I 1.2 times as long as II, and terminal flagellomere 2.0–3.0 (HT: 2.7) times as long as preceding one; sensilla placodea present on flagellomere III and following all flagellomeres.

Mesosoma ( Figs. 5 View FIGURE 5 I, 6 I, 7 I, 8 I): lower margin of pronotum angulate ( Fig. 5 View FIGURE 5 I); upper end of epomia distant from upper margin of pronotum in lateral view ( Fig. 5 View FIGURE 5 I); lateral area of pronotum punctate except for smooth area on lower 0.2–0.3 ( Fig. 5 View FIGURE 5 I); mesoscutum with weak notaulus on anterior 0.3; smooth area around episternal scrobe rather large; upper end of epicnemial carina reaching lower 0.2 of pronotum; juxtacoxal carina present ( Fig. 5 View FIGURE 5 M); all carinae of propodeum present, anterior part of lateromedian longitudinal carinae coalescent ( Fig. 8 View FIGURE 8 I); all areas of propodeum punctate, area superomedia partly smooth ( Fig. 8 View FIGURE 8 I).

Fore wing: Cu-a distant from Rs&M by 0.6–0.8 (HT: 0.8) times length of Cu-a; ICI 0.8–1.2 (HT: 1.0). Hind wing: NI 3.3–6.7 (5.0); one basal hamulus, 5 distal hamuli.

Hind femur 4.8–5.2 (HT: 4.8) times as long as deep in lateral view; hind tibia 7.8–8.5 (HT: 8.2) times as long as deep in lateral view; hind tarsomere ratio I; II; III; IV; V = 3.0; 1.3; 0.9; 0.5; 0.9.

Metasoma: TI 1.3–1.4 (HT: 1.3) times as long as maximum width, with median dorsal carina on near anterior 0.4, without distal depression, and lateral margin weakly convex basally ( Fig. 10 View FIGURE 10 I); TII and TIII without weak round convexities; subgenital plate covered with shallow and fine punctures. Ovipositor upcurved in posterior half ( Fig. 11 View FIGURE 11 L); ovipositor sheath 0.5–0.6 (HT: 0.5) times as long as hind tibia.

Coloration ( Figs. 6 View FIGURE 6 I, 7 I, 9 J, 12 M): body black, except for: mandible with small obscure yellow spot; yellow palpi; antenna blackish-brown with brown ventral side; fore and mid legs yellow (trochanters and trochantelli whitish-yellow) except for coxae; apex of hind trochanter yellow; hind trochantellus yellow; base of hind femur yellow; hind tarsal segments with narrow yellow area; wing veins blackish-brown except for yellow of extreme wing base; stigma blackish-brown; metasomal tergites except for TI reddish brown; metasomal sternites reddishbrown to blackish-brown except for membranous area yellow; ovipositor yellow to yellowish-brown. Black area of hind leg sometimes brownish-brown. Red area on metasomal tergites sometimes darkened except for lateral sides always red.

Male (n=5). Very similar to female: body length 4.5–4.7 mm; length of fore wing 3.8–4.0 mm. Face 0.7–0.8 times as long as wide. Antenna with 23 flagellomeres; terminal flagellomere 1.4 times as long as preceding one. TI 1.4–1.6 times as long as maximum width; inner margin of paramere slightly concave apically in ventral view ( Fig. 11 View FIGURE 11 I).

Coloration similar to female ( Fig. 12 View FIGURE 12 N), differing as follows: mandible brown except for apex; antenna blackish-brown except for brown ventral side in basal part.

Type series. Holotype: female [Honshu] Yamanashi Pref., Koushu city, Yanagisawa-toge, 1480–1580 m, N35°46’44" E138°48’10", 5. viii. 2008, K. Watanabe leg. ( NIAES).

Paratypes (16Ƥ 533): [Honshu] 1Ƥ, Iwate Pref., Mt. Hayachine, 1000m alt., 8–15. viii. 1989, H. Makihara & M. Sharkey leg., Malaise trap ( AEI); 1Ƥ, Tochigi Pref., Oku-nikko, Yumoto, 9. viii. 1980, K. Konishi leg. ( NIAES); 1Ƥ, Tochigi Pref., Nikko, 24. viii. 1980, M. Miyazaki leg. ( NIAES); 1Ƥ, Nagano Pref., Kamikochi, 24. vii. 1954, Townes Family leg. ( AEI); 233, same locality and collector, 25. vii. 1954 ( AEI); 2Ƥ, Nagano Pref., Shimashima-dani, 1300–1700 m, 27. vii. 1980, H. Takemoto leg. ( NIAES); 1Ƥ13, same locality and collector except for altitude are 1000–1300 m, 2. vii. 1980 ( NIAES); 4Ƥ, same locality, 1000–1300 m, 28. vii. 1980, K. Maeto leg. ( NIAES); 1Ƥ, Nagano Pref., Shimotakai-gun, Yamanouchi town, Nagaike, 22. viii. 2007, K. Watanabe leg. (TUA); 1Ƥ13, Shizuoka Pref., Ikawa vil., Nikenkoya, 18–20. viii. 1957, J. Minamikawa leg. ( NIAES). [Shikoku] 2Ƥ 13, Ehime Pref., Saijyo city, Ibukiyama, 13. viii. 1998, R. Matsumoto leg. ( OMNH).

Distribution. Japan (Honshu and Shikoku) ( Fig. 13 View FIGURE 13 ).

Etymology. The specific name is from the Latin “ montanus ” (mountain), referring to their habitat.

Remarks. This species is closely similar to ezoensis sp. nov. and femoralis in some morphological characters (see remarks of ezoensis ), and can be distinguished from them by the 17 or 18 segmented flagellum (16 segmented in femoralis ), the hind tibia 7.8–8.5 times as long as deep in lateral view (8.7–8.9 times in ezoensis ), the TI 1.3–1.4 (in female) or 1.4–1.6 (in male) times as long as wide (1.2–1.3 (in female) or 1.7 (in male) times in ezoensis ), the Cu-a of fore wing distant from Rs&M by more than 0.6 times length of Cu-a (less than 0.5 times in femoralis ) and the metasomal tergite tinged red at least posterior segments (black or only slightly tinged red in ezoensis ).

This species was collected at the shade or edge of wet broadleaf or coniferous forests in mountains (usually over 1000 m in altitude). Adult wasps were mostly captured in nets on bamboo grasses, Sasa sp. ( Fig. 14 View FIGURE 14 C).