| 1a. | Antennae nine-segmented | Brachymyrmex depilis |
| 1b. | Antennae twelve-segmented | 2 |
| | | |
| 2a. | Thorax smooth, convex profile | Camponotus |
| 2b. | Thorax not a smotth, convex profile | 3 |
| | | |
| 3a. | Maxillary palps short, 3-segmented | Lasius subgenus Acanthomyops |
| 3b. | Maxillary palps longer, 6-segmented | 4 |
| | | |
| 4a. | Frontal carinae prominent, ocelli distinct, large | Formica |
| 4b. | Frontal carinae small or indistinct, ocelli vage, small | 5 |
| | | |
| 5a. | Antennal scapes surpassing occipital margin by at least 1/3 length, usually longer; erect hairs on body long and brown or black | Prenolepis imparis |
| 5b. | Antennal scapes shorter; erect body hairs short and golden; small (generally < 0.5 cm), yellow or brownish; mesonotum pyramidal in profile | Lasius |
