Key to species of the Neoryssomus (based on Hofmann (1970))

1. Elytra with greenish metallic shine; elytral punctation dispersed and disordered; antennomere III three times longer than IV; last antennomere as long as the previous two; length 3.5 to 4.75 mm (Chile)..................... N. germainii (Crotch)

1’. Elytra entirely black or black with reddish border; prothorax black; 3rd antennomere two times longer than the 4th; length 3.3 to 3.65 mm (Chile).................................................................. N. variabilis (Korchefsky)