The Diapriidae

Seventh tergite clearly separated from the eighth, slightly transverse, or at least not longer than its basal width and thickly to densely hairy; seventh and eighth tergites together not at all compressed laterally, the eighth sometimes extremely small; epomia distinct more or less from front coxa to tip of pronotal shoulder

Seventh tergite not clearly separated from the eighth and forming with it a long very narrow triangle which is polished and at most very sparsely hairy; seventh and eighth tergites together strongly laterally compressed; epomia less well developed and defined only at the pronotal collar