The Neotropical species of Pristaulacus Kieffer with acute anterolateral projections on the mesonotum are revised. Twenty-one species are included, distributed from Mexico to northern Argentina: P. ambiguus (Schletterer), P. anteruber Smith, n. sp., P. argutus Smith, P. biannulatus Smith, n. sp., P. brasiliensis (Kieffer), P. decemdentatus Kieffer, P. femurrubrum Smith, P. haemorrhoidalis (Westwood), P. haemorrhoidellus (Westwood), P. maculatus (Schletterer), P. nobilis (Westwood), P. omnis Smith, n. sp., P. punctatus Smith, P. ruficeps (Westwood), P. ruficollis (Cameron), P. sexdentatus Kieffer, P. spinifer (Westwood), P. tria Smith, P. tridentatus Smith, P. vittatus Smith, n. sp., and P. zonatipennis Roman. A key separating this group of species from other Pristaulacus and to species is provided.