Key to species of Loneura from Brazil (males)

Loneura brasiliensis Roesler, is not included, because only female specimen(s) is known.

1. Hypandrium of three sclerites, two small, elongate side sclerites flanking a large, central sclerite (see Fig. 10 in Cutrim et al., 2021b).............................................................................. Loneura group I....2

- Hypandrium of one sclerite, resulting from the fusion of the proximal ends of the side sclerites to the central sclerite, this extended mesally on each side, with two posterior processes in the middle, variously shaped (see Fig. 29 in Cutrim et al., 2021b)............................................................................... Loneura group II...3

2. Central sclerite of the hypandrium with one posterior projection, distally bifurcated, with a postero-lateral connection joining the central and lateral sclerites (see Fig. 10 in Cutrim et al., 2021b).......................... L. manauara Cutrim et al.

- Hypandrium with more than one posterior projection......................................................... 4

3. Posterior projections of the hypandrium near to each other, projected from the middle, distally curved outward, with deep median incision that reaches near the base (see Fig. 29 in Cutrim et al., 2021b)...................... L. duckei Cutrim et al.

- Posterior projections of the hypandrium widely separated, projected from the postero-lateral corners, distally curved inward, without deep median incision (see Fig. 33 in Cutrim et al., 2021b)............................... L. amazonica (New)

4. Central sclerite of the hypandrium with two posterior projections, with pointed apices (Fig. 44)................................................................................................... L. maracaensis García Aldrete

- Central sclerite of the hypandrium with more than two posterior projections....................................... 5

5. Central sclerite of the hypandrium with three posterior projections............................................... 6

- Central sclerite of the hypandrium with four projections, two posterior and two latero-mesal (see Fig. 4 in Cutrim et al., 2021b)......................................................................... L. digitiformis Cutrim et al.

6. Posterior border of the central sclerite of the hypandrium without a median process, only a lobulated area (see Fig. 35 in Cutrim et al., 2021b)......................................................................... L. baiana Lima et al.

- Posterior border of the central sclerite of the hypandrium with a median process (see Fig. 17 in Cutrim et al., 2021b)...... 7

7. Posterior border of the central sclerite of the hypandrium with a short, distally rounded median process and two lateral straight projections (see Fig. 17 in Cutrim et al., 2021b)......................................... L. marinonii Cutrim et al.

- Posterior border of the central sclerite of the hypandrium with a long, distally rounded median process and two lateral curved outward projections (Fig. 11)........................................................... L. cavernicola sp. nov.