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

Published as part of González-Mozo, Laura & Mckamey, Stuart H., 2024, A new genus and four new species of Darnini (Hemiptera: Membracidae) from South America, pp. 169-180 in Zootaxa 5415 (1) on page 172, DOI: 10.11646/zootaxa.5415.1.8, http://zenodo.org/record/10692802