The following key to Leptanillinae genera is based on Xu (2012).
Note that this key is for workers and does not include two genera (Phaulomyrma and Yavnella) that are only known from males.
- Mandibles subtriangular, masticatory margins shorter than or subequal to inner margins, the former with 3-5 teeth. Antennal insertions very close to the anterior margin of the head. Body very slender (Old World Tropics and Temperate Regions) => Leptanilla
- Mandibles elongate, masticatory margins much longer than inner margins, the former with many more than 5 minute saw-like denticles or slender peg-like teeth. Antennal insertions well behind the anterior margin of the head. Body relatively robust => 2
- Masticatory margins of mandibles with many minute saw-like denticles. In profile view, promesonotum high and strongly convex. Metanotal groove deeply depressed. Petiole broadly attached to the postpetiole (Indo-Australian) => Anomalomyrma
- Masticatory margins of mandibles with many slender peg-like teeth. In profile view, promesonotum low and weakly convex. Metanotal groove shallowly notched. Petiole narrowly attached to the postpetiole => 3
- In profile view, mandibles massive, lateroventral margin furcated and with 2 teeth. Postpetiole broadly attached to anterior face of gaster. Ventral face of postpetiole concave. In dorsal view, anterior margin of gaster deeply concave (Oriental) => Furcotanilla
- In profile view, mandibles slender, lateroventral margin not furcated and without teeth. Postpetiole narrowly attached to anterior face of gaster. Ventral face of postpetiole convex. In dorsal view, anterior margin of gaster almost straight (Southern Palaearctic, Oriental, and Indo-Australian) => Protanilla