First record of the genus Palpostilpnus Aubert (Ichneumonidae: Phygadeuontinae) from Vietnam, with descriptions of eight new species Author Pham, Nhi Thi Institute of Ecology and Biological Resources, Vietnam Academy of Science and Technology, 18 Hoang Quoc Viet, Hanoi 10072, Vietnam. Author Sheng, Mao-Ling 0000-0003-0141-4697 Center for Biological Disaster Prevention and Control, National Forestry and Grassland Administration, No. 58 Huanghe North Street, Shenyang 110034, China. Author Park, Clara 0009-0008-7781-2935 Biodiversity and Environmental Change Lab, School of Biological Sciences, University of Hong Kong, Kadoorie Biological Sciences Building, Pokfulam Road, Hong Kong SAR, China. clarapark.jh@gmail.com Author Tran, Duong Dinh 0000-0002-6598-7964 Institute of Ecology and Biological Resources, Vietnam Academy of Science and Technology, 18 Hoang Quoc Viet, Hanoi 10072, Vietnam. duongflo@yahoo.com 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. alexey.reshchikov@gmail.com text Zootaxa 2024 2024-10-02 5514 6 525 549 http://dx.doi.org/10.11646/zootaxa.5514.6.2 journal article 10.11646/zootaxa.5514.6.2 1175-5326 13914863 30365787-D444-45E6-96C0-B894FB331262 Palpostilpnus meovacensis Pham, Sheng, Park, Tran & Reshchikov , sp. nov. ( Figures 2H , 10 ) Material examined. Holotype : ♀ ( IEBR ), VIETNAM , Ha Giang Province , Meo V ạc, Chi San , 23°08’20”N 105°22’33”E , 1,235 m a.s.l. , 1 May–30 June 2024 , Malaise trap , Pham T .N. coll. Diagnosis. Reddish yellow body with black markings; occipital carina complete dorsally; postero-ocellar distance 0.8× ocular-ocellar distance; ventral side of F8 onwards of female flattened and thickened; propodeum without carina, except short stubs of lateromedian longitudinal carina and lateral longitudinal carina posteriorly; area postero-externa incomplete. Description of holotype . Face 1.2× as wide as high, granulose, with setae, centrally weakly convex. Clypeal suture indistinct. Clypeus 1.7× as wide as high, convex, coriaceous, with setae, ventral margin weakly impressed. Mandible stout, weakly narrow to apex, teeth sharp, lower tooth slightly longer than upper tooth. Malar space polished, with sparse punctures, 0.5× as wide as mandibular basal width ( Fig. 10A ). Gena subpolished, finely punctate, with setae. Frons and vertex with rugose punctate, posterior portion from behind ocelli to occipital carina steeply sloping. Postero-ocellar distance 0.8× ocular-ocellar distance, 0.8× median ocellus diameter ( Fig. 10B ). Antenna with 24 flagellomeres, ventral side of F8 onwards flattened and thickened. Occipital carina complete. FIGURE 10. Palpostilpnus meovacensis sp. nov. , holotype female: A. head, frontal view; B. head, dorsal view; C. propodeum; D. mesosoma, lateral view; E. mesonotum; F. tergites; G. ovipositor (scale bar = 0.2 mm). Mesosoma. Pronotum punctate dorsally. Epomia present ( Fig. 10D ). Mesoscutum as long as its maximum width, with dense punctures, anterior margin slightly protruding above pronotum ( Fig. 10D ). Notaulus absent. Scutellum moderately convex, subpolished, densely punctate, with setae basally, impunctate posteriorly, lateral carina present basally ( Fig. 10E ). Mesopleuron polished, finely punctate, with setae, except impunctate medially; epicnemial carina distinct on ventral 0.6 of mesopleuron. Sternaulus shortly impressed behind epicnemial carina. Metapleuron densely punctate, with setae. Juxtacoxal carina absent ( Fig. 10D ). Propodeum gradually sloping in lateral view ( Fig. 10D ), subpolished, with dense punctures, except smooth area at level area petiolaris, without carinae except short stubs of lateromedian longitudinal carina and lateral longitudinal carina posteriorly. Area postero-externa incomplete ( Fig. 10C ). Spiracle small, oval. Wings. Fore wing length ca. 4.1 mm , vein 1cu-a interstitial to M&RS, inclivous, postero-distal corner of subbasal cell ca. 70°, vein 3rs-m absent, vein 2rs-m about 2.0× length of M between 2rs-m and 2m-cu, length of CU between 1m-cu&M and 2cu-a 1.3× length of 2cu-a. Hind wing with distal abscissa of CU present, obsolescent towards wing margin, length of CU between M and cu-a 2.0× length of cu-a. Legs. Inner profile of basal portion of fore basitarsus distinctly bent. Hind coxa with distinct punctures. Hind femur 3.8× as long as its maximum width, 0.8× as long as hind tibia length. Hind basitarsus 0.5× as long as tarsus. Metasoma. T1 2.2× as long as apical width, polished, sparsely punctate medially, posteriorly densely punctate, with dorso-lateral carinae; petiole flat; postpetiole broad; ventrolateral carina distinct; spiracle small, round. T2 onwards densely punctate, with setae. T2 1.9× as long as basal width, 1.1× as long as apical width ( Fig. 10F ). Ovipositor very thin, ovipositor tip slightly up-curved; ovipositor sheath slightly longer than as hind tibia, 1.9× as long as hind basitarsus, distinct longer than apical depth of metasoma ( Fig. 10G ). Colour. Reddish yellow with black markings. Head black, mandible (except apex), palpi yellow, scape and ventral part of pedicel yellow, flagellomeres black. Mesoscutum with brown area medially. Hind trochanter, hind femur and hind tibia black apically. T1 entirely black, T2–T5 each with a transverse black band. Male. Unknown. Comparative notes. This new species resembles P. melinhensis by the general colouration and the long ovipositor which is distinct longer than than apical depth of metasoma. It can be recognized from the latter by the shorter postero-ocellar distance (0.8× as long as ocular-ocellar distance vs. 1.7×), combined area superomedia and area petiolaris of propodeum absent (vs. open anteriorly), elongate T2 (1.9× as long as basal width, 1.1× as long as apical width vs. 1.1× and 0.6×, respectively), fore wing vein 1cu-a interstitial to M&RS (vs. postfurcal to M&RS) and juxtacoxal carina on metapleuron absent (vs present in P. melinhensis ). In addition, this new species has entirely black flagellomeres and T1. Etymology. The species name refers to the type locality, Meo Vac district. Distribution. Currently known only from secondary forest at Chi San Nature Reserve, Meo Vac district, Ha Giang Province .