A new species of Gonatopus Ljungh, 1810, G.jaliscanus sp. n., from Jalisco, Mexico, is described and illustrated. In the Neotropical region, G.jaliscanus is similar to G.forestalis Olmi, 1998, but it is distinguished by the black mesosoma (except prothorax, mesoscutum, and mesoscutellum that are yellow), and the metapostnotum being granulated and not rugose; in G.forestalis the mesosoma is completely black and the metapostnotum is granulated and strongly rugose. In the Nearctic region, the new species is morphologically similar to G.curriei Krombein, 1962, but it is distinguished by the dull and granulated metapostonotum; in G.curriei the metapostnotum is shiny and unsculptured. The new species belongs to Gonatopus group 7. The keys to the females of the Nearctic and Neotropical species of this group are modified to include the new taxon.
Keywords: Chrysidoidea; Gonatopodinae; keys; taxonomy.