Key to the species of Celetrigona, workers

1 Basal half of scape with 3–7 robust, erect bristles, very long, 2.6–4.3x scape diameter or more (Fig. 7); on pedicel and fl.1 erect bristles short, no longer than 1.5x fl.3 diameter (Acre, Brazil, San Martin, Peru, Fig. 16)...................... .................................................................................................................................................... C. euclydiana sp. nov.

- Basal half of scape with slender bristles, shorter than or equal to scape diameter; if longer, only 1–3 bristles just on base of scape, no longer than 2.3x scape diameter. Variable on pedicel and fl.1 (Figs. 5, 6, 8)................................... 2

2 Bristles on posterior surface of fl.1 longer, about 2.5–4.5x fl.3 diameter (Fig. 8), following flagellomeres with a sequence of long erect bristles to progressively shorter, aligned (Fig. 9) (Rondônia, southwestern Amazonas, Fig. 16) ............................................................................................................................................ C. hirsuticornis sp. nov.

- Bristles on fl.1 shorter, no longer than 0.8–2.0x fl.3 diameter; erect bristles on following flagellomeres shorter than fl.3 diameter, approximately of uniform length ............................................................................................................ 3

3 Erect bristles on apical half of scape scarce, shorter than or equal to those on basal half (Fig. 5); no modified bristles on apex of scape (southern Amazon to Central Brazil, Peru and Bolivia, Fig. 16) .......... C. longicornis (Friese, 1903)

- Erect bristles on apical half of scape abundant, as long as or longer than on basal half; some recurved bristles on apex of scape (Fig. 6) (northern Amazon to Guiana and French Guiana, Fig. 16) ...................... C. manauara sp. nov.