A taxonomic review of the genus Exochus Gravenhorst (Hymenoptera: Ichneumonidae: Metopiinae) from South Korea with descriptions of ten new species Author Choi, Jin-Kyung Department of Life Sciences, Yeungnam University, Gyeongsan, South Korea; Author Kolarov, Janko Faculty of Pedagogy, University of Plovdiv, Plovdiv, Bulgaria Author Lee, Jong-Wook Department of Life Sciences, Yeungnam University, Gyeongsan, South Korea; text Journal of Natural History 2016 2016-05-31 50 2327 2367 http://dx.doi.org/10.1080/00222933.2016.1197335 journal article 21247 10.1080/00222933.2016.1197335 9e8a020a-c322-48a0-935d-ae3ff9c1f1c2 1464-5262 3993034 B28700A7-9CA7-4AE7-9816-9C8F4CD46160 Exochus dentisternum Lee & Choi sp. nov. ( Figures 1e , 3e , 6e ) Specimens examined Holotype : male, type depository: YNU; ( South Korea ) GW, Hongcheon-gun , Bukbang , Gwangwon Prov. Environment Research Park, 15 – 30 May 2012 , leg. S.J. Jang. Description Male. Forewing 3.5 mm , body 4.5 mm long. Colour. Black. Upper half of face, scape from below, a couple oflateral spots on clypeus, mandible, palpi, tegula, tip of scutellum, apex of femora, base of tibiae and tarsal segments except last one yellow; legs reddish; flagellum from below light brown. Head. Moderately narrowed behind eyes. Frons weakly concave behind base of antennae. Antenna with 23 flagellomeres. First flagellomere 2.5 times as long as wide, second flagellomere square. All other flagellomeres elongated. Diameter of ocellus as long as distance between eye and lateral ocellus. Temple 0.7 times as long as transverse diameter of eye. Occipital carina present only laterally. Face rather strongly convex longitudinally ( Figure 3e ). Front tentorial pits not visible. Combined face and clypeus 1.2 times as high as wide, coarsely and densely punctate, the distance between points shorter than their diameter. Malar space with not deep furrow, 0.62 times as long as basal width of mandible. Apical margin of clypeus straight. Lower tooth of mandible much shorter than upper tooth, but distinct. Mesosoma . 1.6 times as long as high in lateral view. Epomia moderately strong, notaulus present as a small pit on front part of mesoscutum. Scutellum and mesopleuron rather swollen. Prepectal carina reaching subtegular ridge. Hind margin of mesosternum projected backward as a couple of teeth. Sternaulus distinct on front third of mesopleuron. Metapleuron without any setae. Radial vein of forewing originated from middle of pterostigma. Vein Rs+M gradually curved. Vein Cu-a postfurcal as 0.5 of its length. Hindwing with five distal hamuli. Vein cu-a of hindwing intercepted in lower 0.25, vein Cu1 of hindwing faint. Propodeum fully areolated. Area basalis confluent with area superomedia. Combined area superomedia and area basalis convergent in front ( Figure 6e ). Area dentipara with few long setae on hind outer corner. Propodeal spiracle 2.0 times as long as wide, situated a little closer to pleural than to lateral longitudinal carina. Front half of justacoxal carina widened as a lamella. Legs moderately stout, hind femur 2.2 times as long as wide, ratio between length of hind tarsal segments as 22: 10: 8: 5: 10. Front spur of hind tibia 0.5 times as long as hind spur. Metasoma. Median longitudinal carinae of tergite 1 extending to 0.6 of its length. Tergite 2 0.7 times as long as wide apically. Metasomal tergites moderately coarsely and densely punctate, the distance between points longer than their diameter. Epipleuron of tergite 3 semicircular, the basal three-quarters of edge moderately strongly curved. Female. Unknown. Etymology From mesosternum projected backward as couple of teeth. Distribution South Korea . Remarks The species is close to Exochus bicoloripes Kusigemati, 1971 , but differs by its longer malar space, lower number of flagellar segments, presence of costula, elongated propodeal spiracle, metanotum without any setae and coloration of the body.