The red imported fire ant is the most common and troublesome species of ant in the southeastern United States.
Winged males are black and have colorless to pale brown wing veins.
Winged females are mostly light brown. Distinguishing among species of ants in the genus Solenopsis is difficult. The smooth, white, ellipsoidal egg is only about 0.35 mm long. The worker larva grows from 0.2 mm when newly hatched to 2.4 mm in length when fully grown. Larvae from 0.4 to 4.5 mm develop into winged adults.