Key to species of Neotriplax of mainland China

1. Pronotum width/length ratio> 2.0 ...................................................... N. rubens (Hope)

- Pronotum width/length ratio <= 2.0............................................................................. 2

2. Head brown with clypeus black, densely punctured; posterior border of pronotum slightly narrowed backwards, with a broad lobe in middle .................. N. arisana Miwa

- Head black with basal area brown, sparsely punctured; posterior border of pronotum strongly narrowed backwards, with a narrow lobe in middle .......... N. minima, sp. nov.