The Diapriidae

postscutellum with a prominent angular process; scape very long, fully equal to the width of the head as seen from above; rims of the antennal sockets united, at their own level, by a a transverse keel. (gaster beyond petiole very narrow, bright reddish-yellow) (part)

postscutellum without such a process; scape shorter, considerably shorter than the width of the head seen from above; antennal sockets not united by such a keel (formerly Xenotoma Kieffer)