Key to Lepidocyrtus (Fractocyrtus) species

1 Ant III sense organ finger-shape (Fig. 14A); interocular chaetotaxy with 2 scales and 3 chaetae (Fig. 14B); postlabial chaetotaxy with 1 or 2 spines (Fig. 14E); trochanteral organ with about 28 spine-like chaetae (Fig. 18D); Brazil ............... 2

- Ant III sense organ clubbed-shape (Fig. 7A); interocular chaetotaxy with 5 ciliate chaetae (Fig. 7B); postlabial chaetotaxy with 3 spines (Fig. 7E); trochanteral organ with about 34 spine-like chaetae (Fig. 11D); Colombia ......................... 3

2 Head depigmented, or if present, weakly on the side (Fig. 2); head An series with 11 mac and A series with 1 extra mac; collophore posteriorly with 19–28 chaetae and lateral flap with 7 ciliate chaetae; Central Amazon from Brazil (Fig. 19)........................................................................ L. (Fractocyrtus) amazonaensis nom. nov.

- Head anteriorly and laterally pigmented (Fig. 13); head An series with 15–16 mac and A series with 2 extra mac (Fig. 14B); collophore posteriorly with 43 chaetae and lateral flap with 8–11 ciliate chaetae (Fig. 18E); Occidental Amazon (Fig. 19)....................................................................... L. (Fractocyrtus) chicomendesi sp. nov.

3 Body depigmented, if present, only on Th II laterally and coxae (Fig. 6); head An series with 14–15 mac (Fig. 7B); cephalic groove with 7 chaetae (Fig. 7E); Abd III with 5 lateral mac and 27 chaetae on lateral tuft (Fig. 9A); collophore anteriorly with 34 chaetae, posteriorly with 36 chaetae and lateral flap with 18 ciliate and 8 smooth chaetae (Fig. 12A); Colombian Andes (Fig. 19).................................................................... L. (Fractocyrtus) andensis sp. nov.

- Head, Th II to Abd III completely pigmented; head An series with 13 mac; cephalic groove with 5 chaetae; Abd III with 3 lateral mac and 9 chaetae on lateral tuft; collophore anteriorly with 25 chaetae, posteriorly with 43 chaetae and lateral flap with 12 ciliate and 15 smooth chaetae; Colombian Amazon (Fig. 19)............................................................................................. L. (Fractocyrtus) mateosi Cipola & Bellini, 2018 (in Cipola et al. 2018b)