A new enigmatic genus of the ichneumonid subfamily Ctenopelmatinae (Hymenoptera, Ichneumonidae) from Thailand Author Ranjith, Avunjikkattu P. 0000-0001-7061-9659 Integrative Insect Ecology Research Unit, Department of Biology, Faculty of Science, Chulalongkorn University, Bangkok, Thailand Author Quicke, Donald L. J. Integrative Insect Ecology Research Unit, Department of Biology, Faculty of Science, Chulalongkorn University, Bangkok, Thailand Author Reshchikov, Alexey 0000-0001-9866-5139 Biodiversity and Environmental Change Lab, School of Biological Sciences, University of Hong Kong, Kadoorie Biological Sciences Building, Pokfulam Road, Hong Kong SAR, China Author Butcher, Buntika A. 0000-0002-0541-0709 Integrative Insect Ecology Research Unit, Department of Biology, Faculty of Science, Chulalongkorn University, Bangkok, Thailand text Journal of Hymenoptera Research 2024 2024-06-04 97 491 504 journal article 298080 10.3897/jhr.97.121436 10c23bd8-542a-4a25-9803-d60ad495d7f6 1B48635F-A630-4A27-A22C-4B6BEA2E1D5B Thaictenopelma splendida Ranjith, Reshchikov & Quicke sp. nov. Type material. Holotype . Thailand • ♀ , Nan Province , Doi Phu Kha National Park ; 19 ° 12.236 ' N , 101 ° 04.667 ' E , altitude 1,341 m . a. s. l. 5–6 July 2022 , Malaise trap , Worapong Atsawasiramanee leg.; Malaise trap ( CUMZ ) . Paratypes : Thailand • 2 ♂ , Thailand, Nan province , Pua district , Doi Phu Kha National Park , 19 ° 10.450 ' N , 101 ° 06.370 ' E alt. 1677 m , 7–20. ix. 2018 , Malaise trap , coll. Worapong Atsawasiramanee ( CUMZ ) ; 1 ♀ , Chiang Mai Province , Doi Pha Hom Pok National Park , Doi Pha Luang ; 20 ° 1.06 ' N , 99 ° 9.581 ' E , altitude 1,449 m . a. s. l., 27 Jul. – 3 Aug. 2007 , Malaise trap , T 2932 , Wongchai P. leg.; ( QSBG ) ; 1 ♀ & 1 ♂ ; same sampling data but 3–10 Aug. 2007 , T 2931, Wongchai P. leg. ( QSBG ) ; 1 ♂ same sampling data but 7–14 Oct. 2007 , T 6209, Wongchai P. leg.; ( QSBG ) . Description. Female ( holotype ) : Body length 8.5 mm , fore wing length 7.8 mm . Head . Antenna with 42 flagellomeres, all longer than wide, flagellomeres narrowing towards apex, F 1 1.5 × as long as F 2, F 1 & F 2 2.4, 1.8 × as long as wide, respectively. Scape approximately as long as maximally wide (Fig. 1 B ). Head transverse 1.5 × as wide as high in anterior view, 1.8 × as wide as long in dorsal view. Face transverse, flat, distinctly punctate with granulate interspace, setose, 2.0 × as long as wide (Fig. 1 B ). Inner margin of eyes parallel (Fig. 1 B ). Clypeus transverse, 3.5 × as long as wide, sepatated from face by distinct suture (Fig. 1 B ). Malar space 0.4 × as long as basal width of mandible. Lower tooth of mandible 1.6 × as long as upper tooth. Gena 0.6 × as long as eye in lateral view, 0.7 × as long as transverse diameter of eye in dorsal view. Frons distinctly punctate with granulate interspace, setose (Fig. 2 A ). OOL 2.1 × OD ; OOL 1.9 × POL . Vertex and occiput distinctly punctate with granulate interspaces (Fig. 2 A ). Mesosoma . Mesosoma 1.4 × as long as high. Pronotum rugose punctate with indistinct groove laterally, setose (Fig. 2 C ). Propleuron distinctly punctate, setose (Fig. 2 C ). Scutellum 0.7 × as long as wide, moderately punctate with smooth interspace, setose (Fig. 2 D ). Propodeum with area superomedia 1.0 × as long as wide, anterior transverse carina straight laterally, lateral extension of posterior transverse carina distinctly curved (Fig. 2 E ). Wings . Pterostigma 3.4 × as long as wide. Fore wing areolet 0.8 × as long as maximum width. Vein 2 rs-m 1.5 × as long as 3 rs-m. Legs . Hind femur, tibia and basitarsus 5.4, 5.7, 5.9 × as long as its maximum width, respectively. Metasoma . T 1 1.0 × as long as its maximum width. T 2 0.7 × as long as its maximum width. T 2 1.1 × as long as T 3. T 3 0.6 × as long as its maximum width. Ovipositor sheath 0.2 × as long as hind basitarsus. Coloration . Body mostly black except the following yellow: face and clypeus except medially, mandible except apically, gena postero-basally, frons laterally, pronotum antero- and postero-laterally, mesopleuron posteriorly, scutellum, axilla, metanotum mediobasally and postero-laterally, metapleuron except anterior blackish patch, propodeum except area externa, fore leg, mid coxa, mid femora, mid tibia, mid basitarsus except apically, hind coxa dorsally and baso-ventrally, hind tibia medially, T 1 mediobasally, posterior margin of T 1, anterior and posterior margin of T 2, anterior margin of T 3 and ovipositor; the following brown: antenna except medially, hind coxa apico-ventrally, hind trochanter and femur, hind tibia basally and apically, hind basitarsus basal 1 / 3 rd, venation, pterostigma, hind basitarsus apically, hind tarsus 2–3, tarsal claw brown; and the following white: antenna medially, medial tarsomere 4–5, hind basitarsus apical 2 / 3 rd , hind tarsomere 2–5. Variation . In paratypes from Doi Pha Luang antenna with 39 flagellomeres, occiput more strongly concave, area superomedia with transverse carina more strongly arched posteriorly. Clypeus completely black except apically, metapleuron and anterior part of propodeum black, T 2 baso-laterally black. Male. Same as female except the following characters; Clypeus transverse, 3.2 × as long as wide, clypeal margin protrtuding anteriorly (Fig. 5 A ). Scape 1.4 × long as its maximum width (Fig. 5 A ). Face transverse, flat, shallowly punctate with shagreen matt interspace, setose, 1.6 × as long as wide. Malar space 0.3 × as long as basal width of mandible. Lower tooth of mandible 1.8 × as long as upper tooth. T 1 1.5 × as long as its maximum width. T 2 0.6 × as long as its maximum width (Fig. 5 B ). Posterior margin of S 4 and S 6 rounded, of S 5 straight (Fig. 5 C ). Apex of paramere elongate, its margin round (Fig. 5 C ). Inner margin of ventral side of paramere parallel at base (Fig. 5 C ). Tip of aedeagus swollen, decurved, its apex rounded. Yellow colored areas relatively larger than in female, those face and clypeus completely, mesopleuron, middle part of T 1 between latero-median carina yellow. Figure 5. Thaictenopelma splendida Ranjith, Reshchikov & Quicke , gen. et sp. nov. , paratype, male A head, anterior view B propodeum and T 1–3 dorsal view C S 4–6 and male genitalia ventral view. Biology. Unknown. Etymology. The species is named after the magnificent combination of morphological characters which are completely unknown from the members of the subfamily. Distribution. Thailand .