Illustrated key to genera and catalogue of Mymaridae (Hymenoptera) in America north of Mexico Author Huber, John T. Author Read, Jennifer D. Author Triapitsyn, Serguei V. text Zootaxa 2020 2020-05-12 4773 3 1 411 journal article 22231 10.11646/zootaxa.4773.1.1 d1ca4b58-0fd8-4bcb-8f81-12fc2c106b55 1175-5326 3821373 B1D8D67C-4FDC-477E-872F-E8BCD4D027FB CARAPHRACTUS Walker, 1846 ( Figs 246–273 ) Caraphractus Walker, 1846: 49 (key), 50 (description). Type species: Caraphractus cinctus Walker, 1846 , by monotypy. Valkerella Westwood, 1879: 584 (footnote). Type species: Polynema natans Lubbock, 1864 , by monotypy. Walkerella Dalla Torre, 1898: 425 . Unjustified emendation. Diagnosis . Body length 795–1250 μm. Head, mesosoma, petiole and coxae heavily sculptured with isodiametric reticulations ( Figs 246–250 , 253, 254 ); antenna with clava 1-segmented and widening towards apex ( Fig. 252 ); fore wing with 1 distal macrochaeta, apparently without marginal vein, and with parastigmal and stigmal veins together as long as submarginal vein ( Fig. 251 ). FIGURE 246 . Caraphractus cinctus Walker ,habitus.Canada, Ontario, 3.4 km NNE Almonte, 45°15'N 76°10'W, 12–28.vii.1993, F.W. Grimm, alvar. Scale bar=500 μm. FIGURES 247–251 . Caraphractus cinctus Walker. 247, head, ventroanterior; 248, head, posterior; 249, head, dorsal; 250, head, lateral; 251, wings. Scale bars: 247–250=100 μm; 251=200 μm. FIGURES 252–254 . Caraphractus cinctus Walker. 252, antenna; 253, mesosoma + petiole, dorsal; 254, mesosoma + petiole, lateral. Scale bars=200 μm. FIGURES 255–257 . Caraphractus cinctus Walker , metasoma. 255, dorsal; 256, genitalia seen through gaster; 257, lateral. Scale bars=200 μm. FIGURES 258–263 . Caraphractus cinctus Walker. head. 258, dorsoanterior; 259, posterior. 260, lateral; 261, dorsal; 262, ventral; 263, mouthparts. Scale bars=50 μm. FIGURES 264–273 . Caraphractus cinctus Walker. 264, mesosoma, dorsal; 265, mesosoma, ventral; 266, mesosoma, lateral; 267, frenum–propodeum; 268, metasoma, dorsal; 269, metasoma, ventral; 270, metasoma, lateral; 271, petiole, dorsal; 272, petiole, ventral; 273, petiole, lateral. Scale bars: 264–267=50 μm; 268–270=100 μm; 271–273=20 μm. Discussion . Among the nine other Nearctic genera of the Polynema group ( Acmopolynema , Cnecomymar , Eustochus , Kalopolynema , Mymar , Neomymar , Palaeoneura , Polynema , Stephanodes ), Caraphractus is the sister genus to Eustochus . Together they form a distinct subgroup distinguished by their heavily sculptured head, mesosoma, and petiole. Nearctic hosts . Coleoptera : Dytiscidae . Important reference . Triapitsyn (2011a) .