[Pest Profile]

THIEF ANT

Order/Family: Hymenoptera/Formicidae 
Scientific Name: Solenopsis molesta (Say)

Description
Thief ants are very tiny ants. The thorax lacks distinct spines, the petiole has two nodes, and there is a small stinger at the tip of the abdomen. Thief ants are yellow to light brown and look much like Pharaoh ants.

Biology
These ants begin swarming as winged reproductives in June; this activity continues until late fall. A colony of a few hundred to several thousand workers can be established by a single fertilized female. Developmental time (egg to adult) is 50 days to several months.

Habits
Thief ants are often found in very large nests that have tiny tunnels connecting to the nests of larger ants. Thief ants usually nest outdoors in areas with bare soil or under stones. When they do nest in structures, they usually are found in wall voids and similar protected locations. Thief ants feed on live and dead insects, seeds and honeydew. They will tend aphids and other honeydew-producing insects as a source of food.

Control
All cracks and gaps in exterior walls that provide access to voids or interior areas should be sealed. All debris from the exterior of the structure and other items on the ground where these ants nest should be removed. Thief ants prefer high- protein foods; however, they might respond to sweet baits. Baiting might be ineffective because these ants usually stop feeding on the bait before enough is consumed to eliminate the colony. Protein baits are the most effective; however, if acceptance is low, a sweet bait should be considered.
 The most effective control is accomplished when ant trails are followed to find and treat the nest with a residual insecticide. Exterior nests should be drenched with a liquid formulation. Nests within wall voids are more easily treated by aerosol injection or application of a dust formulation. When nests cannot be located, a barrier spray should be applied to foundations and the soil immediately adjacent to the building.