Key to the Neotropical and Nearctic adult males of Monopelopia

1. Wing length c. 1.0 mm; Brazil ................................................................................ M. minuta Serpa-Filho & Oliveira

-. Wing length> 1.0 mm .................................................................................................................................................. 2

2. Second palpomere with one or two preapical dark spines; USA, Colombia ........................ M. boliekae Beck & Beck

-. Second palpomere without dark preapical spines......................................................................................................... 3

3. Second palpomere with pale subapical setae c. 84 µm; temporals single .................................................................... 4

-. Second palpomere with pale subapical setae subequal its length; temporals single to multiserial; USA, Europe......... ................................................................................................................................................ M. tenuicalcar (Kieffer)

4. T VIII brown; T IX with 3–5 setae on each side .......................................................................................................... 5

-. T VIII pale; T IX with one seta on each side; Jamaica ........................................................... M. mikeschwartzi Epler

5. HR c. 1.31, gonostylus at least 114 µm; USA .................................................................... M. tillandsia Beck & Beck

-. HR> 1.48, gonostylus <104 µm................................................................................................................................. 6

6. Wing length c. 1.39 mm; middle tibia without preapical long seta; Brazil .................................................................... .................................................................................................................. M. caraguata Mendes, Marcondes & Pinho

- Wing length c. 1.85 mm; middle tibia with one preapical c. 137 long seta; Brazil .................... M. paranaense sp. n.