Xynobius duoferus Han & van Achterberg, 2024

Han, Yunjong, van Achterberg, Cornelis & Kim, Hyojoong, 2024, Four new species of the genus Xynobius Foerster (Hymenoptera, Braconidae, Opiinae) from South Korea, ZooKeys 1193, pp. 219-243 : 219

Xynobius duoferus Han & van Achterberg sp. nov.

Figs 29 , 30-41

Type material.

Holotype. ♀ (NIBR), "South Korea: Jangam Cave, Pyeongchang-gun, Gangwon prov., 37°23'54.2"N, 128°25'24.2"E, 11.vii.2020, SW [= collected by sweeping], Hyojoong Kim leg., KSNU".

Diagnosis.

Dorsope distinct (Fig. 37 ); first metasomal tergite with straight longitudinal striae; notauli complete and narrowly crenulate (Fig. 32 ); mesoscutum largely smooth and sparsely setose medially; second tergite striate-rugose medially; 20th to 26th antennal segments of ♀ white followed by two dark apical segments.

Description.

Female; length of body 2.0 mm, of fore wing 2.5 mm.

Head. Antenna with 28 segments and 1.6 × longer than body; third segment of antenna 5.8 × longer than wide and 1.1 × longer than fourth segment (Figs 39 , 41 ); depression of frons present near antennal sockets (Fig. 34 ); eye ~ 2.5 × longer than temple in dorsal view (Fig. 35 ); frons and vertex smooth, glabrous and moderately setose; face largely shiny, smooth and densely setose, but granulate latero-dorsally; median keel present; clypeus twice wider than its maximum height (Fig. 34 ); clypeus semi-circular, moderately setose, and ventral margin of clypeus straight and above upper level of condyles of mandible; hypoclypeal depression present; length of maxillary palp nearly 0.9 × as long as height of head; malar sulcus absent; occipital carina absent dorsally; mandible triangular in lateral view, hardly twisted and gradually widened basally (Fig. 34 ).

Mesosoma. Mesosoma 1.4 × longer than its height; pronotal side largely smooth and smooth groove present along its ventral margin; propleuron smooth and sparsely setose, without transverse carinae; mesopleuron largely smooth and sparsely setose antero-dorsally and postero-ventrally, but precoxal sulcus oblique, medium-sized and densely crenulate; epicnemial area smooth (Fig. 31 ); mesopleural sulcus smooth; anterior groove of metapleuron smooth; metapleuron reticulate-rugose and moderately setose (Fig. 31 ); notauli complete on disc of mesoscutum and narrowly crenulate; mesoscutum smooth, largely glabrous but middle lobe sparsely setose (Fig. 32 ); medio-posterior depression of mesoscutum round and shallow; scutellar sulcus wide and crenulate (Fig. 32 ); scutellum largely smooth and glabrous, rather flat in lateral view and protruding above level of mesoscutum; propodeum rugose with long medio-longitudinal carina, transverse carinae, and areola, remainder of propodeum largely smooth (Figs 32 , 36 ).

Wings. Fore wing (Fig. 30 ): pterostigma triangular and rather directly narrowed apically; vein 1-SR+M almost straight; vein 3-SR sublinear with vein r, converging with vein 2-M and 1.6 × longer than vein 2-SR; vein 2-SR almost straight; vein SR1 straight, 2.0 × longer than vein 3-SR; vein 1-M straight; r: 3-SR: SR1 = 5: 40: 84; vein m-cu distinctly postfurcal, converging to vein 1-M posteriorly and angled with vein 2-M; first subdiscal cell transverse and closed; vein CU1b present. Hind wing (Fig. 30 ): vein m-cu absent; vein 1r-m 0.8 × as long as vein 1-M; vein 2-M pigmented.

Legs. Hind femur 4.5 × longer than its maximum width (Fig. 29 ).

Metasoma. First metasomal tergite 1.5 × longer than its apical width; first tergite gradually widened apically and its surface densely longitudinally striate postero-medially, and remainder of tergite shiny and smooth (Fig. 37 ); dorsope present and surrounded by strongly curved dorsal carinae (Fig. 37 ); second metasomal suture absent dorsally (Fig. 33 ); second tergite striate-rugose medially except a pair of droplet-shaped impressions anteriorly; following tergites shiny, smooth and moderately setose posteriorly (Fig. 33 ); setose part of ovipositor sheath ~ 1.2 × longer than first tergite and 0.1 × as long as fore wing (Fig. 38 ).

Colour. Body generally brown to black (Fig. 29 ); entire head, transverse band below the precoxal sulcus, tarsi, inside of dorsope, and first and second tergites dorsally dark brown; legs, remaining tergites, ovipositor, and basal segments (1st-6th) of antenna brown; palp pale yellowish or white; apical segments (20th-26th) of antenna white to white-brown; pterostigma and veins of wings pale brown; wings subhyaline.

Distribution.

South Korea.

Biology.

Unknown.

Etymology.

Name derived from duo (Latin for two) and - fero (suffix in Latin meaning carrying or having), because of the two apical dark antennal segments.

Remarks.

This species runs to Xynobius notauliferus Li & van Achterberg, 2013 in the key by Li et al. (2013). It differs by having the length of maxillary palp 0.9 × height of head (1.4 × in X. notauliferus ), face smooth, but granulate latero-dorsally (smooth), clypeus twice wider than high (1.6 × wider than its maximum height), first metasomal tergite 1.5 × longer than its apical width (length 1.3 ×), antenna of ♀ with two apical antennal segments dark brown (6 or 7 such segments), pterostigma directly narrowed distally (gradually narrowed) and outer side of hind femur without brownish patch (with patch).

Figures

Figure 29. Xynobius duoferus Han & van Achterberg, sp. nov., holotype, ♀, habitus, lateral.

Figures 30 - 41. Xynobius duoferus Han & van Achterberg, sp. nov., holotype, ♀ 30 wings 31 mesosoma, lateral view 32 mesosoma, dorsal view 33 metasoma, dorsal view 34 head, anterior view 35 head, dorsal view 36 propodeum, dorsal view 37 1 st metasomal tergite, dorsal view 38 ovipositor and its sheath, lateral view 39 basal part of antenna 40 apical part of antenna 41 antenna.