Syzeuctus longigenus UCHIDA , 1940

Riedel, Matthias, 2021, The genus Syzeuctus FÖRSTER in the Western Palaearctic region and Central Asia (Hymenoptera, Ichneumonidae, Banchinae), with descriptions of 17 new species, Linzer biologische Beiträge 52 (2), pp. 1013-1098 : 1054-1055

Syzeuctus longigenus UCHIDA, 1940 , new ♂ ( Figs 8 , 21 , 45, 86, 132)

O r i g i n a l: Syzeuctus longigenus UCHIDA, 1940: 27

H o l o t y p e: (♀) " Mongolei, Apaka, VI.1939 " (Sapporo), type not studied, high-resolution photos of holotype seen.

S t u d i e d m a t e r i a l: 22♀♀, 8♂♂; Mongolia.

D e s c r i p t i o n: ♀: Body length 8-9.5 mm. Antenna with 33-35 flagellomeres; 1 st flagellomere 4.0× longer than wide and 0.55× as long as eye; preapical flagellomere 1.1- 1.3× longer than wide. Temple moderately and roundly narrowed behind eye, dorsally c. 0.4× as long as eye. OED 1.6-1.8× and OOD 2.0× ocellar diameter. Frons rather densely punctate, moderately swollen laterally and impressed medially. Face densely punctate. Clypeus 1.8-1.9× wider than long, with scattered punctures, apical margin rounded. MI 0.85-0.9. Genal carina reaching mandibular base.

Mesosoma with coarse dense punctures, 1.5× longer than high. Frontoventral edge of pronotum moderately curved; lateral pronotal groove smooth. Epicnemial carina low, without or with ± distinct low carina in transversal part, with low carina on pleural part. Speculum punctate. Propodeum with complete apical transversal carina. Hind femur 4.8- 4.9× longer than wide. Hind metatarsus 0.7× as long as hind femur. 2 nd hind tarsomere 1.3× longer than 3 rd one. Hind claw with long teeth, moderately curved apically. Areolet stalked; 2 nd recurrent vein in its middle. Nervulus almost interstitial. Hairs on basal cell much shorter than their intervals. Hind wing with 8 distal hamuli.

Metasoma stout. 1 st tergite 1.35-1.45× longer than wide, with rather dense coarse punctures laterally. 2 nd tergite 1.05-1.15× wider than long, with dense punctures. 3 rd tergite 1.1-1.2× wider than long, with dense punctures. Ovipositor 1.2-1.35× longer than

fore wing, 1.5-1.7× longer than metasoma and 3.0-3.2× longer than hind tibia.

Color: Mainly yellow. Flagellum reddish, black basally; scape sometimes yellow ventrally. Head yellow; mandibular teeth, median stripe on face, frons medially, stemmaticum and occiput black. Mesosoma mainly yellow; three stripes on mesoscutum, scuto-scutellar groove, ventral and posterior margins of pronotum, wide margins of mesopleuron, mesosternum, margins of metapleuron and two oblique paramedian stripes on propodeum black. 1 st to 5 th tergites red, with wide apical yellow bands. 1 st to 3 rd tergites with subbasal and lateral yellow bands. 6 th and 7 th tergites often brownish. Fore and mid legs yellow, fore and mid femora often with brown dorsal stripes. Hind coxa and trochanter black, hind coxa yellow dorsally; hind trochantellus yellow; hind femur and tibia yellow, reddish or blackish ventrally. All tarsi reddish-yellow. Wings hyaline; pterostigma brown, yellowish proximally.

♂: Body length 8-9 mm. Antenna with 35-36 flagellomeres; 1 st flagellomere 3.8× longer than wide and 0.5× as long as eye; preapical flagellomere 1.4× longer than wide. Temple shortly parallel behind eye and moderately narrowed apically. OED 1.7-1.8× and OOD 2.3-2.4× ocellar diameter. Face finely punctate, shining. Inner eye margins slightly divergent ventrally. Clypeus 1.7× wider than long, with scattered punctures, apical margin rounded. MI 1.0-1.1. Genal carina reaching mandibular base.

Epicnemial carina low, without carina on transversal part. Speculum punctate. Propodeum with complete apical transversal carina. Hind femur 5.0-5.3× longer than wide. Hind metatarsus 0.7× as long as hind femur. 2 nd hind tarsomere 1.2× longer than 3 rd one. Hind claw with long teeth. Areolet stalked; 2 nd recurrent vein in its middle. Nervulus postfurcal by 1-2× its width. Hairs on basal cell much shorter than their intervals. Hind wing with 8 distal hamuli.

1 st tergite 1.5× longer than wide, with rather dense coarse punctures laterally. 2 nd tergite 1.0-1.1× wider than long, with dense punctures. 3 rd tergite 1.0-1.1× wider than long, with dense punctures.

Color: Mainly yellow. Flagellum reddish, black basally; scape yellow ventrally. Head yellow; mandibular teeth, median stripe on face, frons medially, stemmaticum and occiput black. Mesosoma mainly yellow; three stripes on mesoscutum, scuto-scutellar groove, ventral and posterior margins of pronotum, wide margins of mesopleuron, mesosternum, margins of metapleuron and two oblique paramedian stripes on propodeum black. 1 st to 3 rd tergites with subbasal and lateral yellow bands. Fore and mid legs yellow, fore and mid femora often with brown dorsal stripes. Hind coxa and trochanter partly black, hind coxa yellow dorsally; hind trochantellus yellow; hind femur and tibia yellow, ± reddish ventrally. All tarsi reddish-yellow. Wings hyaline; pterostigma brown, yellowish proximally.

Hosts unknown.

Figures

Figs 7-9: Habitus of ♀♀ from dorsal: (7) Syzeuctus mongolicus nov.sp. HT, (8) S. longigenus UCHIDA, (9) S. rufigaster nov.sp. HT.

Figs 19-21: Habitus from lateral: (19) Syzeuctus mongolicus nov.sp. HT, (20) S. persicus nov.sp. HT, (21) S. longigenus UCHIDA.