Syzeuctus achterbergi, Riedel, 2022

Riedel, Matthias, 2022, Contribution to the knowledge of Oriental Syzeuctus FÖRSTER (Hymenoptera, Ichneumonidae, Banchinae), with description of six new species, Linzer biologische Beiträge 54 (1), pp. 257-273 : 258-263

Syzeuctus achterbergi nov.sp. ( figs 4 , 10 , 16 , 22 )

H o l o t y p e: (♀) Indonesia: C Sulawesi, nr Luwuk, Salodik, c 400 m, 21-31.X.1989, Mal. trap 14, C. v. Achterberg, RMNH´89 (Leiden).

P a r a t y p e: (♀) Indonesia: C Sulawesi, nr Luwuk, Bunga, c 300 m, 1-14.XI.1989, Mal. trap 16, C. v. Achterberg, RMNH´89 (coll. RIEDEL).

E t y m o l o g y: This species is dedicated to C. VAN ACHTERBERG who made important contributions to the knowledge of Oriental Hymenoptera .

D e s c r i p t i o n: ♀: Body length 9 mm. Length of fore wing 7 mm and of ovipositor 7 mm. Antenna with 39-40 flagellomeres; 1 st flagellomere 4.2× longer than wide and 0.49-0.51× as long as eye; preapical flagellomere square. Temple very short, strongly and roundly narrowed behind eye, dorsally 0.2× as long as eye. OED 1.2× and OOD 1.5× ocellar diameter. Vertex and frons coarsely and densely punctate. Frons moderately swollen laterally and strongly concavely impressed medially. Face densely punctate, inner eye margins slightly divergent ventrally. Clypeus 2.0× wider than long, with rather dense punctures, apical margin rounded. MI 0.6-0.7. Mandible with strong baso-ventral lamella, upper tooth larger than lower one.

Mesosoma coarsely and densely punctate, 1.45× longer than high. Frontoventral edge of pronotum moderately curved. Side of pronotum densely punctate dorsally, with fine longitudinal striae ventro-posteriorly, pronotal groove partly smooth. Epicnemial carina low, pleural part present, transversal part weak. Mesopleuron partly with dense punctures, medially and posteriorly with scattered punctures; speculum large, smooth. Propodeum with coarse transversal rugose-punctation. Pleural carina present. Apical transverse carina of propodeum strong and complete. Hind femur 5.0-5.2× longer than wide. Hind metatarsus 0.54× as long as hind femur. 2 nd hind tarsomere 1.35-1.45× as long as 3 rd one. Hind claw with c. 4 long teeth, strongly bent apically.

Areolet with long stalk; vein 2mc-u reaching areolet in its distal 0.8. Vein 1cu-a slightly postfurcal by 1-2× its width. Postnervulus intercepted in its middle. Nervellus of hind wing slightly reclivous, intercepted in its apical 0.75-0.80. Hind wing with 7-9 distal hamuli.

Metasoma rather slender, tergites with narrow spiracles, spiracles not or slightly bulged. 1 st tergite 1.85-1.95× longer than wide, smooth medially, with rather dense and coarse lateral punctures. 2 nd tergite 1.4× and 3 rd tergite 1.3-1.4× longer than wide, both densely punctate but smooth in apical 0.2. Ovipositor 1.0× as long as fore wing, 1.25× longer than metasoma and 2.5× longer than hind tibia.

Color: head and mesosoma black, with extensive cream-yellow coloration. Flagellum brown. Palps, mandible except teeth, clypeus, face except dorso-median black spot, wide frontal orbit, malar space and outer orbit, ventral spot on pedicel, frontal and upper margins of pronotum, spot on tegula, subtegular ridge, hook-shaped anterolateral spots and roundish central spot on mesoscutum, dumb-bell shaped stripe on mesopleuron, upper division and posterior spot on metapleuron, sides and apex of scutellum, postscutellum and transverse stripe on apical propodeum yellow. Metasoma reddish; 1 st tergite creamyellow basally and with yellow apical band. Legs red; fore and mid coxae and trochanters cream-yellow, hind coxa ± black in basal half. Fore wing with brown apical stripe; pterostigma brown.

♁ unknown.

R e m a r k: This new species belongs to the villosus group sensu CHANDRA & GUPTA (1977) and runs to S. villosus (CAMERON, 1899) in their key of Oriental Syzeuctus (CHANDRA & GUPTA 1977: 138-139) . It differs by its longer ovipositor and different coloration of legs and 1 st tergite.

Figures

Figs 4-9: Basal tergites from dorsal: (4) Syzeuctus achterbergi nov.sp. ♀ HT; (5) S. floresiensis nov.sp. ♀ HT; (6) S. genator nov.sp. ♀ HT; (7) S. laoticus nov.sp. ♀ HT; (8) S. orientalis nov.sp. ♁ PT; (9) S. siamensis nov.sp. ♀ HT.

Figs 10-15: Faces from frontal: (10) Syzeuctus achterbergi nov.sp. ♀ HT; (11) S. floresiensis nov.sp. ♀ HT; (12) S. genator nov.sp. ♀ HT; (13) S. laoticus nov.sp. ♀ HT; (14) S. orientalis nov.sp. ♁ HT; (15) S. siamensis nov.sp. ♀ HT.

Figs 16-21: Heads from frontal: (16) Syzeuctus achterbergi nov.sp. ♀ HT; (17) S. floresiensis nov.sp. ♀ HT; (18) S. genator nov.sp. ♀ HT; (19) S. laoticus nov.sp. ♀ HT; (20) S. orientalis nov.sp. ♁ HT; (21) S. siamensis nov.sp. ♀ HT.

Figs 22-23: Mesosoma from lateral: (22) Syzeuctus achterbergi nov.sp. ♀ HT; (23) S. genator nov.sp. ♀ HT.