Key to species of Polyodontotrochus

1. Pronotum with suprahumeral horns distinctly curved upward (Fig. 1)..................................... P. elevatus

- Pronotum with suprahumeral horns slightly curved upward (Figs.11, 14) or straight (Fig. 13)......................... 2

2. Suprahumeral horns in dorsal view curved upward, apex of the horns extends beyond the most anterior part of the metopidium (Figs. 11, 14); aedeagus without longitudinal subdivision at apex (Figs. 31, 32).................................... 3

- Suprahumeral horns in dorsal view straight, apex of the horns does not extend beyond the most anterior part of the metopidium (Fig. 13); aedeagus with longitudinal subdivision at apex (Fig. 37).......................................... P. inpa

3. Forewing s crossvein absent, R2+3 and R4+5 fused at apex; aedeagus in lateral view compressed (Fig. 23)... P. auriculatus

- Forewing s crossvein present, R2+3 and R4+5 not fused at apex; aedeagus in lateral view sinuate (Fig. 34).................................................................................................. P. extentapalaestrus