Key to species of Decliviassus (males) from China (modified from Dai et al. 2015)

1. Dorsal coloration pale yellow, without numerous small black spots; style apex slender, not footlike (Figs. 33, 36, 48)...... 2

- Dorsal coloration dull stramineous, with numerous small black spots; style apex broadened, footlike (Fig. 32)..................................................................................... D. maculatus Dai, Dietrich & Zhang

2. Pronotum with pair of brown submarginal spot, aedeagus in lateral view with apex bent posterad (Fig. 31)..................................................................................... D. bipunctatus Dai, Dietrich & Zhang

- Pronotum without spots, aedeagus in lateral view with apex curved anterad (Figs. 34–35, 49–50)...................... 3

3. Aedeagus base with two prolonged straps (Figs. 34–35).............................. D. nudus Dai, Dietrich & Zhang

- Aedeagus base without prolonged strap (Figs. 49–50)......................................... D. sagittatus sp. nov.