Key to the species of Paradelius de Saeger, 1942

1. Antenna with 22 antennomeres (Figs 1A, 3A)............................................................... 2

– Antenna with 20 antennomeres.......................................................................... 3

2. Metasomal tergites yellow (Fig. 2B); metapleuron smooth (Fig. 1D); propodeal areola smooth without medial transverse carina (Fig. 1F).................................................................. Paradelius flavus Ranjith sp. nov.

– Metasomal tergites brown (Fig. 4B); metapleuron striate (Fig. 3D); propodeal areola sculptured with indistinct medial transverse carina (Fig. 3F)........................................................... Paradelius striatus Ranjith sp. nov.

3. Second metasomal suture indistinct; sternaulus not distinctly impressed; second metasomal tergite smooth................................................................................ Paradelius ussuriensis Belokobylskij, 1988

– Second metasomal suture distinct; sternaulus distinctly impressed; second metasomal tergite longitudinally striate........ 4

4. Second metasomal tergite smooth posteriorly; propodeal areola with indistinct medial transverse carina; hind wing vein cu-a not sclerotized......................................................... Paradelius ghesquierei de Saeger, 1942

– Second metasomal tergite longitudinally striate completely; propodeal areola without indistinct medial transverse carina; hind wing vein cu-a sclerotized................................................ Paradelius chinensis He & Chen, 2000