Odorous Ant

Odorous Ant: Facts, Identification & Control

Latin Name:Tapinoma sessile


Dark reddish-brown to black and 1/10-inch long. Antennae have 12 segments.


Nests found in a great variety of situations. Inside buildings, they are often found nesting in the walls or beneath the floor. They are most likely to invade buildings during rainy weather. They travel in trails, foraging day and night.


Honeydew melons in the wild. Inside buildings, they prefer sweet items.


Each female in the nest lays one egg a day; young reach adulthood in an average of 24 days; workers and females live for several years.

Because odorous house ants tend to forage inside homes, they can easily contaminate human food supplies. While odorous house ants do not sting or bite, they can become persistent pests, traveling indoors in large numbers.

Odorous house ants are small, measuring between 1/16 and 1/8-inch in length. They have dark brown or black bodies with one node on their petiole, which is hidden by their abdomens. Odorous house ants have an unevenly shaped thorax when viewed from the side. The most distinguishable characteristic of odorous house ants is the smell of rotten cocoanut that is emitted when their bodies are crushed.

Odorous house ants are opportunists, nesting both indoors and outdoors. Indoors, odorous ants can nest in wall crevices, near heaters, water pipes, under carpets, beneath floors or sometimes behind paneling. Outdoors, odorous house ants place their shallow nests beneath soil as well as in logs, mulch, debris, and under rocks.

Like all ants, odorous house ants live in colonies. Each colony may contain two or more queens and over 10,000 workers. The queens of an odorous ant colony can produce thousands of workers and hundreds of reproductives. The reproductives are the future queens.

Odorous house ants forage for food night and day. Outdoors they prefer honeydew from aphids and mealybugs. When the honeydew supply is reduced in autumn, they often move indoors for food. Indoors, they eat meats, sugary foods, dairy products, pastries, cooked or raw vegetables, and fruit juices.

When alarmed by a predator, worker odorous ants will move in quick, erratic motions, raising their abdomens into the air.