Monomorium pharaonis is an ant species that is likely native to Africa, but this species has become well established all over the world, including the US. These ants are fast-moving and excessively small in size, and they are widely considered to be among the most difficult ant pests to eliminate from homes. The workers that appear throughout homes are only 1.5 to 2 mm in length and their body color ranges from yellow to brown or even red, but they often appear to be uniformly dark in color due to their small size. When viewed under magnification, it’s clear that Pharaoh ant workers have dark brown to black abdomens, and thousands of workers can be found in a mature colony.
Pharaoh ants are well known for nesting within inaccessible indoor areas where temperatures range from 80 to 86 degrees, and relative humidity is around 80 percent. Their nests are most frequently found in wall voids and beneath floors on the upper levels of homes and buildings and beneath subfloors. Unlike many ant species, Pharaoh ants do not reproduce during seasonal swarms; instead, these ants reproduce solely within their nests. Pharaoh ants are major indoor pests in the northeast US, where they often appear in heated homes during the winter season. Over-the-counter pest control products are ineffective at controlling these ant pests, and some forms of pest control can make infestations worse.
Pharaoh ants are notable for their ability to establish new nests rapidly. These nests are known as “satellite nests,” and they are formed after a queen ant and several workers leave the “parent nest.” Combatting indoor infestations with repellent insecticides or baits can make infestations worse by causing the ants to scatter, which increases the chances that they will establish multiple satellite nests throughout a home. This is why non-repellent insecticides have become the control method of choice when dealing with indoor Pharaoh ant infestations.
Have you ever found tiny ants in your home during the winter?