Pharaoh ants derived their name as a result of being mislabeled as one of the 10 plagues of Biblical Egypt. These are small (1/16-1/8 inch) monomorphic (same size) ants, yellowish to light reddish brown in color. They are a cosmopolitan pest, found in Canada and the United States. They will nest anywhere in a structure preferring warm temperatures. They are serious pests in hospitals and health care facilities. Pharaoh ants are omnivorous, feeding on a wide variety of foodstuffs.
Pharaoh ant colonies can exist with many nests and queens with several hundred thousand workers. Their sheer numbers makes this an economically significant pest. Colonies will divide (budding) with the slightest stress. They will move and start many new sub-colonies within the structure. Consistent baiting is the recommended control technique.