Key to species of the genus Sinodorcadion Gressitt
1 Ventral surface distinctly punctate........................................................................ 2
- Ventral surface not punctate, elytra with a distinct posteromedial transverse band............... S. subspinicolle Breuning
2 Scape without coarse punctures.......................................................................... 3
- Scape with sparse and coarse punctures................................................ S. punctuscapum sp. nov.
3 Mesosternum with punctures............................................................................ 4
- Mesosternum without punctures............................................................. S. jiangi sp. nov.
4 Lateral pronotal tubercle small, antennomeres dull reddish brown, elytra with vague mottled maculae...................................................................................................... S. punctulatum Gressitt
- Lateral pronotal tubercle well developed, antennomeres 3–11 blackish brown apically, elytra with conspicuous pubescent mac- ulae........................................................................... S. magnispinicolle sp. nov.