Ichneumon deliratorius Linnaeus, 1758 Ichneumon deliratorius Linnaeus, 1758: 562, ♂. Ichneumon flavitarsis Smith, 1874: 389, ♂, high-resolution photos of type studied. syn. nov. Holotype of I. deliratorius : ♂ “20. Deliratorius ” (Linnean Society/London), type not studied. Holotype of I. flavitarsis : ♂ “ Japan ” (NHM, London). Non-type material: JAPAN: 1 ♂, Niigata Pref., Nagaoka City, Suyshi Town, Mt. Nakogiri-yama, 37.23°N 138.55°E, 680–765 m, 28.vi.2014, S. Shimizu leg. (Sapporo); 2 ♂♂: Nagano Pref., Outaki-mura, Mt. Outake, Hak- kaisan, 1780–1859 m, 4.viii.2017, K. Watanabe leg.; 1 ♂: Nakamura-cho, Nerima-ku, Tokyo, 3.v.1952, R. Ishikawa leg. (Sapporo); 1 ♂: Kanagawa Pref., Ebina-shi, Sagami river, 25.iv.2006, K. Watanabe leg.; 1 ♂: Osaka Pref., Chi- haya-akasaka-mura, Mt. Kongosan, 1056 m, 34.4140°N 135.6776°E, 7–15.vii.2012, S. Fujie leg. Description: ♂: Body length 16‒21 mm. Flagellum with 41‒42 flagellomeres; 1 st flagellomere 2.8× longer than wide. Tyloids on flagellomeres 5/7‒14/17, long-oval or linear, centrally situated, 0.6× as long as the flagellomeres. Temple strongly and almost linearly narrowed behind eye. OED 1.0x and OOD 1.3x ocellar diameter. Frons rugosepunctate. Face coarsely punctate and granulate. Clypeus with scattered punctures, shmooth between punctures. MI 0.2 Gena densely punctate ventrally. Mesosoma with pale hairs. Notaulus impressed in frontal 1/5 of mesoscutum. Mesoscutum coarsely punctate and granulate, shining or ± opaque. Mesopleuron and metapleuron with dense punctures. Scutellum slightly elevated, about as long as wide or slightly longer than wide, densely punctate, lateral carina in basal 0.3‒0.6. Area superomedia about square or halfmoon-shaped, finely rugose; anterior transversal carina weak, in or caudal to its middle. Hind femur 3.5‒4.1× longer than wide. Fore metatarsus usually with apical tooth. Areolet pentagonal, dis- tance between veins 2rs-m and 3rs-m 2‒3× their width, vein 2m-cu in the middle. Vein 1cu-a postfurcal (by 1‒2× its width). Lateral field of postpetiolus 0.5‒0.7× as wide as the median field, median field aciculate or coarsely striate. Gastrocoelus strongly impressed, with longitudinal ridges. Thyridium oblique, 1.0‒1.2× wider than the interval. 2 nd tergite 1.0‒1.2× longer than wide. 2 nd and 3 rd tergites densely rugose-punctate and striate medially; 4 th and 5 th tergites with superficial punctures. 2 nd to 4 th sternites with median membraneous folds. Apical margin of hypopygium with tongue-shaped medial extension. Color: Black, metasoma often with weak bluish shine. Palps ivory. Spot on mandible, labrum, clypeus and face, frontal orbit, scape ventrally, upper margin of pronotum, subtegular ridge, tegula and scutellum. 2 nd and 3 rd tergites with narrow reddish apical margins. Coxae, trochanters and femora black; fore femur frontally and mid femur apically yellowish or reddish; mid femur reddish dorsally; usually hind trochantellus entirely and hind femur narrowly reddish at base. All tibiae and tarsi yellow; hind tibia infuscate in apical 0.4; hind metatarsus (sometimes also 2 nd and 3 rd tarsomeres) with brownish tip. Wings almost hyaline, pterostigma reddish-brown. Remarks: This species has been found in Japan (Uchida 1926, 1935, Momoi 1968, Nakaya 1998). It was transferred to Coelichneumon by Heinrich (1971: 967), mainly due to biological reasons (no overwintering behaviour). The morphological features are charcteristical for the genus Ichneumon, and this taxon was recently re-transferred to Ichneumon (Riedel 2012), a generic position that was confirmed by molecular data (Tschopp et al. 2013). We give a description of the Japanese males here. Lee et al. (2012) recently reported and illustrated a Korean Coelichneumon species which they called “ Coelichneumon flavitarsis ”. This taxon belongs to a different species of the genus Coelichneumon and resembles Coelichneumon pieli Uchida, 1937 from China. Since we were not able to study the type material, we do not formally synonymize both species. Since Coelichneumon flavitarsis is preoccupied, we establish the name Coelichneumon flavitarsator nov. name for this Korean species here. From the material mentioned in Lee et al. (2012), we designate the following lectotype here: ♀: GG, Namhansanseong: 26.v.1966, M.S.Choi (Gyeongsan, Korea). Distribution: Transpalaearctic, Japan, Korea., Published as part of Riedel, Matthias & Watanabe, Kyohei, 2021, The genus Coelichneumon Thomson in Japan (Hymenoptera, Ichneumonidae, Ichneumoninae), pp. 501-545 in Zootaxa 4948 (4) on pages 542-543, DOI: 10.11646/zootaxa.4948.4.2, http://zenodo.org/record/4629337, {"references":["Linnaeus, C. von. (1758) Systema naturae per regna tria naturae, secundum classes, ordines, genera, species cum characteribus, differentiis, synonymis locis. Tom. 1. Edition 10. Holmiae, 824 pp. https: // doi. org / 10.5962 / bhl. title. 542","Smith, F. (1874) Description of new species of Tenthredinidae, Ichneumonidae, Chrysididae, Formicidae etc. of Japan. Transactions of the Entomological Society of London, 1874, 373 - 409.","Uchida, T. (1926) Erster Beitrag zur Ichneumoniden [- Fauna] Japans. Journal of the Faculty of Agriculture, Hokkaido Imperial University, 18, 43 - 173.","Uchida, T. (1935) Zur Ichneumonidenfauna von Tosa (I.) Subfam. Ichneumoninae. Insecta Matsumurana, 10, 6 - 33.","Nakaya, M. (1998) Collection from the natural studies of Morioka city. Report of the Iwate Entomological Society, 25, 13 - 20. [in Japanese]","Heinrich, G. H. (1971) Synopsis of Nearctic Ichneumoninae Stenopneusticae with particular reference to the Northeastern region. Supplement 2. Naturaliste Canadien, 98, 959 - 1026.","Riedel, M. (2012) Revision der westpalaarktischen Arten der Gattung Coelichneumon Thomson (Hymenoptera, Ichneumonidae). Linzer Biologische Beitrage, 44, 1477 - 1611.","Tschopp, A., Riedel, M., Kropf, C., Nentwig, W., Klopfstein, S. (2013) The evolution of host associations in the parasitic wasp genus Ichneumon (Hymenoptera: Ichneumonidae): convergent adaptations to host pupation sites. BMC Evolutionary Biology, 13, 74. https: // doi. org / 10.1186 / 1471 - 2148 - 13 - 74","Lee, J. - W., Jeong, J. - C., Choi, J. - K. & Kim, K. - B. (2012) Arthropoda: Insecta: Hymenoptera: Ichneumonidae: Ichneumoninae. Ichneumon Fly II. Insect Fauna of Korea, 13 (2), 1 - 107."]}