Symplecis vietnamensis Varga, 2025

Varga, Oleksandr, 2025, First records of the genera Gnathochorisis Förster, 1869 and Symplecis Förster, 1869 (Hymenoptera, Ichneumonidae, Orthocentrinae) from Vietnam, Zootaxa 5647 (6), pp. 571-583 : 580-582

Symplecis vietnamensis Varga , sp. nov.

urn:lsid:zoobank.org:act:686D6F52-0E3F-4AEA-89FD-A20C7696F2D0

( Fig. 6 )

Material examined. Holotype: ♀, VIETNAM: Tonkin , Hoang Lien N. R., 10 km SW Sa Pa, ca. 1550 m, Malaise traps, 22–29.x.1999, leg. C. v. Achterberg, RMHN’99, RMNH.INS.1722330 ( RMNH) . Paratypes: 1 ♂, 1 ♀, the same locality as for holotype, but 15 km W Sa Pa , ca. 1900 m, Malaise traps, 15–21.x.1999, leg. C. v. Achterberg, RMHN’99, RMNH .INS.1722331, RMNH.INS.1722332 ( RMNH); 3 ♀♀, Lam Dong, Bidoup Nuiba N.P., near

Da Lat , 1650–1700 m, Malaise trap 1–12, 11–19.x.2005, leg. C. v. Achterberg & R . de Vries , RMHN’05, RMNH . INS.1722333, RMNH.INS.1722334, RMNH.INS.1722335 ( RMNH).

Diagnosis. Symplecis vietnamensis sp. nov. is characterized by the combination of the following characters: face, clypeus and malar space yellow ( Fig. 6B ); antenna with 18–19 flagellomeres, first flagellomere 4.6–4.8 × as long as wide ( Fig. 6J ); pronotum yellow ( Fig. 6E ); mesoscutum evenly and densely pubescent ( Fig. 6G ); propodeum with area superomedia delimited by carinae, 1.2–1.3 × as long as wide, costulae present ( Fig. 6H ); fore wing with vein 3rs-m present; hind wing with nervellus intercepted below the middle ( Fig. 6I ); first metasomal tergite 2.5–2.7 × as long as maximum width; second tergite longitudinally wrinkled, 1.3–1.4 × as long as apical width ( Fig. 6K ); ovipositor 0.5–0.6 × as long as first tarsomere of hind tarsus.

Symplecis vietnamensis sp. nov. is similar to Palaearctic S. bicingulata (Gravenhorst, 1829) in having the yellow face, clypeus and pronotum, and evenly pubescent mesoscutum, but differs by the longer first flagellomere, which is 4.6–4.8 × as long as wide (3.6–3.7 × in S. bicingulata ) and more elongate area superomedia, which is 1.2–1.3 × as long as wide (about 1.0 × in S. bicingulata ). Symplecis vietnamensis sp. nov. resembles the Oriental S. anaeratabettensis in the colouration of face and pronotum, but differs by the black mesopleuron and mesoscutum (largely orange in S. anaeratabettensis ) and more elongate area superomedia (about as long as wide in S. anaeratabettensis ).

Description. Female. ( Figs 6A–B, E–K ). Body length approximately 3.7–4.8 mm. Fore wing 3.0–4.0 mm.

Head ( Figs 6B, E–F, J ) smooth and sparsely pubescent. Antenna with 18–19 flagellomeres, first flagellomere 4.6–4.8 × as long as wide. Face about 0.8–0.9 × as long as wide, smooth and sparsely pubescent; eyes strongly convergent to clypeus, glabrous. Malar space short, 0.2–0.3 × the basal width of mandible; subocular sulcus absent. Clypeus 0.9 × as long as wide, weakly granulate. Mandible bidentate, not twisted, lower tooth shorter than upper tooth. Temples short and strongly narrowed behind eyes (dorsal view). Frons and vertex smooth; length of the ocellar-ocular distance 1.3–1.4 × maximum diameter of lateral ocellus; occipital carina complete.

Mesosoma ( Figs 6E, G–H ) smooth and densely pubescent. Propleuron densely pubescent. Pronotum smooth and glabrous; epomia present, but not reaching mesoscutum. Mesoscutum densely and evenly pubescent; notauli deep anteriorly. Scutellum smooth. Mesopleuron smooth, densely pubescent anteriorly and ventrally; epicnemial carina present; sternaulus deep on anterior 0.4 of mesopleuron. Metapleuron shiny, with traces of granulation, with longitudinal carina in lower third; pleural and submetapleural carinae present. Propodeum smooth, carinated; area superomedia elongate, 1.2–1.3 × as long as wide, costulae present; area basalis not delimited by carinae anteriorly; apophyses absent.

Legs relatively slender; hind femur 5.5–5.9 × as long as wide; third tarsomere of hind tarsus 1.4–1.5 × as long as fifth tarsomere; tarsal claws simple.

Wings ( Fig. 6I ). Fore wing with vein 2rs-m about 0.7 × the distance between 2rs-m and 2m-cu; vein 3rs-m present; vein 1cu-a weakly basad to M&Rs; hind wing with nervellus weakly intercepted below the middle, vertical; distal abscissa of Cu unpigmented.

Metasoma ( Fig. 6K ) longitudinally wrinkled anteriorly and sparsely pubescent. First tergite 2.5–2.7 × as long as maximum width, weakly granulate, longitudinally wrinkled laterally; latero-median carinae present, but weak. Second tergite 1.3–1.4 × as long as apical width, longitudinally wrinkled. The remaining tergites smooth. Ovipositor short, about 0.2 × as long as hind tibia and 0.5–0.6 × as long as first tarsomere of hind tarsus.

Colour.Headblackexceptface,clypeus,malarspace,mandible(exceptapices),scapeandpedicelyellow. Mesosoma black except propleuron, pronotum, tegula and subtegular ridge yellow. Fore and mid legs orange except coxae, trochanters and trochantelli yellow to ivory; hind leg orange except coxa apically, trochanter and trochantellus partly, femur and tibia partly and tarsus entirely brownish. Metasoma with tergites 1–2 black; the remaining tergites brown, except second tergite apically,third tergite basally and apically,and fourth apically yellow.Pterostigma and veins brown.

Male. Generally resembles female, but differs by the longer malar space, weakly narrowed eyes, present subocular sulcus, more abundant yellow colouration of head, and shorter first flagellomere, which is 3.7 × as long as wide ( Figs 6C–D ).

Etymology. The new species is named after the type locality situated in Vietnam. Adjective.

Distribution. Vietnam.

Figures

FIGURE 6. Symplecis vietnamensis sp. nov. A–B, E–G, I–K—holotype female; H—paratype female; C–D—paratype male. A, D—lateral view of habitus; B–C—frontal view of face; E—lateral view of head and mesosoma; F—dorsal view of head; G—dorsal view of mesoscutum; H—dorsal view of propodeum; I—lateral view of wings; J—frontal view of flagellomeres 1–2; K—dorsal view of metasomal tergites 1–3. Scale bars: 0.5 mm (A, D) and 0.1 mm (B–C, E–K).