Imported Fire Ants (Red, black and hybrid)
Solenopis invicta, Slenopsis richteri
Description: The workers range in size, 1/16 inch to 1/4 inch, and are black, reddish brown or red and black. The waist (pedicel) has two nodes. The antennae are 10-segmented with a two-segmented club. These ants respond quickly to nest disturbance and readily sting people and pets. Painful stings result in a pustule that lasts several days.
Life Cycle: Egg » larva » pupa » adult
Where to Look: Outside, colony mounds can be found anywhere from open area in yards, gardens and pastures to areas adjacent to buildings, sidewalks, plants and other structures. Imported fire ants are predators/scavengers on many things, including insects, seeds and wildlife. In buildings, watch for ants trailing, and follow the trail to the nest. They usually nest outside.
Acrobat Ants
Crematogaster spp.
Description: Workers are one size, between 1/16 inch and 1/6 inch depending on species. Color is variable, but frequently the head and thorax are reddish-brown and the abdomen is black. They have two backward-pointing spines on the thorax. The waist (pedicel, the narrow segments at the front of the abdomen) has two nodes and is attached to the upper side of the gaster) part of the abdomen following the waist). The gaster is heart-shaped and often is held upright over the body when the ants are disturbed.
Life Cycle: Egg » larva » pupa » adult
Where to Look: These ants nest in water-damaged or water-stressed wood (similar to carpenter ants). Indoors, they are found in building voids and insulation. Outdoors, they are found in soil, leaves or wood. The will trail and enter buildings by any means. They are active during the day and prefer sweet foods. They often feed on the sugary excretions of honeydew-producing insects (e.g., aphids or scales).
Argentine Ant
Iridomyrex humilis
Description: Workers are one size, between 1/8 inch and light to dark brown. The waist (pedicel) has one node. The tip of the gaster lacks a circle of hairs. They may emit a stale greasy or musty odor when crushed. These ants do not have a stinger.
Life Cycle: Egg » larva » pupa » adult
Where to Look: They usually nest a moisture source. Inside, they are found near water pipes, sinks, potted plants and water leaks. Outside, they are found in moist areas under logs, boards, stones, concrete slabs, debris, mulch, leaves and pine straw. Workers follow trails when foraging. They commonly tend honeydew-producing insect (e.g., aphids). Sweets are the favored food, but they will feed on most any food source.
Carpenter Ant
Camponotus spp.
Description: Workers are many sizes from 1/4 inch to 1/2 inch and black, red or black and red. The waist (pedicel) has one node, and the thorax does not have spines. There is no stinger, and numerous upright hairs are found on the body. The tip of the gaster has a circular fringe of hairs. The thorax is evenly rounded when viewed from the side.
Life Cycle: Egg » larva » pupa » adult
Where to Look: They nest primarily in wood, including live trees with heart rot. They can nest in buildings especially in areas of moist wood. In some areas of the U.S., carpenter ants may damage sound, structural wood to excavate nests. More commonly, carpenter ants nest in existing cavities or in soft or rotting wood of higher moisture content. Smaller species may live in pre-existing void, such as curtain rods, hollow-core doors, between studs in walls and around windows. They are scavengers that eat sweets and some insects. Carpenter ants use trees and other plant material as bridges to enter structures. Look for wood shavings and sawdust discarded from the nest. Follow the trail back to the nest. This procedure is especially effective at night during summer months.
Crazy Ant
Paratrechina Iongicornis
Description: Workers are one size, about 1/8 inch, and their bodies are dark brown to black. The waist (pedicel) has one node. They are small and slender bodied, with long legs and antennae. The top of the gaster has a circular fringe of hairs. Crazy ants have conspicuous, light hairs over their bodies, with four pairs of stiff, hairs on the top of the thorax.
Life Cycle: Egg » larva » pupa » adult
Where to Look: Highly adaptable, these ants live in both very dry and rather moist habitats. Indoors, they nest in wall voids, especially near a heat source. Outdoors, they are fond in cavities in plants and trees, rotten wood, potted plants and under objects in soil, trash and mulch. Their foraging behavior depicts their name, since they appear to run rapidly, aimlessly and apparently exploring their habitat. These ants eat many things but prefer sweets and insects. Locate nests by following the trail of forging workers back from the food source. These ants are attracted to honeydew-producing insects.
Ghost Ant
Tapinoma melanocephalum
Description: Workers are one size, about 1/16 inch. The head and thorax are dark brown to black. The antennae, waist (pedicel), gaster and legs are pale in color. The waist has one flattened node hidden by the base of the gaster. The tip of the abdomen lacks a circle of hairs. These ants emit a nauseous, rotten coconut-like odor when crushed.
Life Cycle: Egg » larva » pupa » adult
Where to Look: Inside, they nest in cabinets, walls and potted plants and behind baseboards. Outside, they can be found under logs, stones, potted plants, etc. These ants prefer sweets but will eat insects. They tend insects for honeydew. Because of their high water requirements, they can be found trailing to water sources.
Pharaoh ant
Monomorium pharanois
Description: The workers are one size, about 1/16 inch. Pharaoh ants are yellow to reddish colored with a dark gaster tip. The waist (pedicel) has two nodes, and the antennae are 12-segmented with a three-segmented club.
Life Cycle: Egg » larva » pupa » adult
Where to Look: They are found in wall voids, behind baseboards, in furniture or in other warm, humid areas near food and water. The colonies tend to be large, have multiple queens and are prone to “budding.” New nests can be formed with as few as five workers, 10 immatures and one queen. Applications of fast-acting liquid or dust insecticides may cause colonies to divide and disperse, worsening the problem. Baits are the preferred treatment tools.
Pavement ant
Tetramorium caespitum
Description: The workers are one size, about 3/16 inch. Pavement ants are brown to black with paler legs and antennae. The waist (pedicel) has two nodes. The antennae are 12-segmented with a three-segmented club. There are distinctive parallel ridges or grooves on the head and thorax. The thorax has a pair of small spines on the upper-back part.
Life Cycle: Egg » larva » pupa » adult
Where to Look: Indoors, nests are found in walls and insulation and under floors. During the winter, they may nest near heat sources. Outdoors, nests are along sidewalks and foundations of buildings, near wood, stones, brick, mulch, etc. They often enter buildings from outside via plumbing penetrations. Pavement ants will feed on most anything but have a preference for oily foods and meats. They also tend honeydew-producing insects.