Key to the Subgenera of the Crematogaster of the Malagasy region: Queens
(as far as queens are known)
1 Antennae 10-segmented. ............................................................................................................................... Decacrema
- Antennae 11-segmented................................................................................................................................................ 2
2(1) Mandibles sickle-shaped with single apical tooth (Fig. 18), very rarely with 4 teeth where apical tooth enlarged and 3 additional normal-sized teeth present; clypeus medially protruding as thin flange over mandibles (Fig. 18) ............
.......................................................................................................................................................................... Oxygyne - Mandibles broad with 4–5 teeth, apical tooth at most slightly enlarged (Fig. 19); clypeus not protruding over mandibles (Fig. 19) ................................................................................................................................................................. 3
3(2) Petiole in dorsal view rectangular (Fig. 12); propodeal spines absent ........................................................ Mesocrema
- Petiole in dorsal view variable, but never rectangular; propodeal spines variable.......................................................4
4(3) Petiole in dorsal view ovo-rectangular (Fig. 13) and with postero-lateral denticles or tubercules; postpetiole without median impression ....................................................................................................................................... Orthocrema
- Petiole shape variable, but never ovo-rectangular, postero-lateral denticles absent; postpetiole variable, but at least posteriorly with weak median impression ............................................................................................. Crematogaster