The genus Pristaulacus Kieffer, 1900 (Hymenoptera: Aulacidae) in Vietnam and Northeastern Laos with descriptions of ten new species Author Pham, Nhi Thi 0001-0002-9304-9863 Institute of Ecology & Biological Resources (IEBR), Vietnam Academy of Science & Technology (VAST), 18 Hoang Quoc Viet Road, Cau Giay, Ha Noi, Vietnam & Graduate University of Science & Technology, Vietnam Academy of Science & Technology (VAST), 18 Hoang Quoc Viet Road, Cau Giay, Ha Noi, Vietnam ptnhi2@yahoo.com Author Long, Khuat Dang Institute of Ecology & Biological Resources (IEBR), Vietnam Academy of Science & Technology (VAST), 18 Hoang Quoc Viet Road, Cau Giay, Ha Noi, Vietnam Author Dzuong, Nguyen Van 0000-0003-2363-0088 Tay Bac University, Son La, Vietnam duongdhtb@gmail.com Author Mai, Pham Quynh 0000-0002-9479-9604 Institute of Ecology & Biological Resources (IEBR), Vietnam Academy of Science & Technology (VAST), 18 Hoang Quoc Viet Road, Cau Giay, Ha Noi, Vietnam & Graduate University of Science & Technology, Vietnam Academy of Science & Technology (VAST), 18 Hoang Quoc Viet Road, Cau Giay, Ha Noi, Vietnam pqmai70@gmail.com Author Turrisi, Giuseppe Fabrizio 0000-0002-5258-367X Museum of Natural History “ La Specola ”, Entomology, University of Florence, via Romana, 17, 50125 Florence, Italy giuseppefabrizio.turrisi@unifi.it text Zootaxa 2024 2024-03-28 5432 2 213 249 http://dx.doi.org/10.11646/zootaxa.5432.2.4 journal article 10.11646/zootaxa.5432.2.4 1175-5326 10898639 86CDBFBF-A565-4C97-AE83-306369B48E5A Genus Pristaulacus Kieffer, 1900 Type-species: Pristaulacus chlapowskii Kieffer, 1900 For taxonomic history, see Turrisi et al . (2009: 53) . The genus Pristaulacus was redefined by Turrisi et al . (2009) within a cladistic framework and is represented in all zoogeographic regions except Antarctica . It can be distinguished from Aulacus by the following combination of characters: occipital carina present (e.g. Figs 2C , 10C ) (absent in Aulacus ), although there are exceptions— Turrisi et al . (2009) found that P. ornatus Kieffer has no occipital carina and A. grossi Jennings, Austin & Stevens has an occipital carina, and more recently A. bamagensis Jennings & Parslow was described with an occipital carina laterally, but absent medially ( Jennings et al . 2018 ); frons usually not sculptured above antennal sockets ( Figs 4B , 6B , 8B ) (sculptured in Aulacus ); tarsal claws pectinate, with three or five tooth-like processes along inner margin (e.g. Figs 2G , 4H , 10H , 14G , 18C ) (with only one weak basal process in Aulacus ); petiole slender, at least 2.5 × as long as wide (e.g. Figs 7A , 8G , 9A, 9D , 14I ) (at most 1.0 × as long as wide in Aulacus ) ( Turrisi et al . 2009 ; Watanabe et al . 2013 ; Jennings et al . 2018 ). Diagnosis . Eyes small, circular or subcircular, remote from the mandibles; antenna with 14 antennomeres in female, 13 antennomeres in male; antennal insertions low on face, near lower margin of eyes; scape usually deeply convex ventrally in lateral view, much thicker than pedicel and flagellomeres; sub-antennal groove or depression to accommodate scape (e.g. Fig. 6B ); metapostnotum between propodeum and metanotum as a distinct sclerotization (deep and wide crenulate groove-like sclerotization) (e.g. Figs 2H , 4F , 8H , 10G , 14H ); propodeum pyramidal, metasoma inserted high on the apex; metasomal T1 and T2 fused dorsally; hind coxa, in females, usually with groove or notch on inner lateral surface, the apposed grooves or notches forming an ovipositor guide ( Figs 3B , 7C , 9B , 13C , 15B , 18B, D ); hind trochanter with a subapical groove dorsally ( Figs 7B , 9C , 13B , 18B, H ), prefemur (trochantellus) more or less present, short (sometimes indistinct ( Figs 7B , 13C , 18B, D, H ); hind tarsal claws pectinate with three to five tooth-like processes along inner margin (e.g. Figs 2G , 4H , 10H , 14G ); fore wings not plicate at rest; fore wing vein 2m-cu present (e.g. Figs 6H , 10I ), vein 2r-m usually present, largely spectral, vein 3r-m present, often largely spectral (e.g. Figs 6H , 10I ); ovipositor exserted, protruding well beyond apex of metasoma.