Key to species of Eurygenys in Madagascar

1 Antenna conspicuously longer than body (Fig 7 a)........................ E. bilbo Rousse, Villemant et Seyrig sp. nov.

- Antenna about the same length or shorter than body.......................................................... 2

2(1) Body entirely pale yellow without any dark marking (Fig. 7 c)............. E. gamour Rousse, Villemant et Seyrig sp. nov.

- Body darker, mostly reddish testaceous to black............................................................. 3

3(2) Face, clypeus and mouthparts uniformly reddish testaceous (Fig. 7 f)... E. kerlioretensis Rousse, Villemant et Seyrig sp. nov.

- Face and clypeus pale yellow with a large medio-longitudinal black marking, mandible blackish (Fig. 7 h).................................................................................................... E. ricinorum Townes