Key to last instar larvae of Polythoridae genera of the PNN Tatamá

1. Prementum 0.20–0.28 longer than its widest part; antennal pedicel 0.25–0.30 longer than scape....................... 2

1’ Prementum 0.10–0.15 longer than its widest part; antennal pedicel 0.55 longer than scape............................ 3

2(1) Hindwing sheaths slender with costal and anal borders parallel; caudal gills blackish-brown, enlarged, with long and slender projections, 2.5–3 times longer than its widest part, lacking glabrous areas; epiproct with 6 projections, paraprocts with 5–6 projections....................................................................................... Cora

2’ Hindwing sheaths broader, with anal border convex; caudal gills yellowish-brown, globose, with short, roundly-pointed projections, one third longer than wide, with large glabrous areas; epiproct with 5 projections, paraprocts with 4 projections.............................................................................................. Miocora

3(1’) Dorsal protuberances on S1–9 slender; caudal gills approx. twice longer than wide; epiproct projection 2 noticeably longer than projections 1 and 3.............................................................................. Euthore

3’ Dorsal protuberances on S1–9 thick; caudal gills approx. 1/3 longer than wide; epiproct projection 2 slightly longer than projections 1 and 3............................................................................. Polythore