Identifying household ants is important so you can get rid of them effectively by using the correct products. Ants have three main body parts: the head, the thorax and the abdomen, which is the end section. However, there are variations in different types of ants. Counting the number of nodes in the petiole -- the section between the thorax and abdomen -- is one important way to identify ants. Household ants have one or two of these nodes.
Place sticky traps in areas where you spot ants. Once you capture an insect you will be able to identify it.
Observe the color of the ant. Odorous ants have dark brown or shiny black bodies and the worker ants are about 1/8 inch long. One node is present on the body and is hidden by the abdomen. A side view of the thorax shows irregularity in the shape. The final key to identifying the odorous ant is to crush the ant by stepping on it. Odorous house ants have a strong odor when killed in this manner.
Look for grooves on the head and thorax. If these are present, the insect is most likely a pavement ant. Other keys to identifying this insect include the dark brown or black color and its size of 3/16 inch. It has two nodes in the petiole and a pair of spines on the back section of the thorax.
Determine if the ant is an Argentine ant. These ants are a dull brown color and have one erect node in the petiole and an uneven thorax when seen from the side. Crush the ant to see if it has a musty odor. Argentine ants emit a musty odor when stepped on and are about 1/8 inch long.
Look for large eyes and three teeth on the front of the head. These are present on the red imported fire ant, which has a reddish color on the body and a dark brown gaster on the abdomen. This ant has two nodes on the petiole and a stinger. This type of ant ranges in size from 1/16 to 1/5 inch long.
Observe the ant body to detect golden hairs on an amber-colored body. The southern fire ant has these characteristics along with a black abdomen. It also has large eyes, two nodes on the petiole and two teeth on the head. This type of ant ranges in size from 1/8 inch to longer than 1/4 inch.
Identify the pharoah ant by its pale colors, ranging from yellow, honey to orange. This ant has two nodes in the petiole and the workers are approximately 1/16 inch long. The pharoah ant does not have spines and the thorax is uneven in size.
Sniff the air wherever you spot black or bicolored black and red ants. Carpenter ants emit a strong odor when disturbed. They are longer than most ants, ranging in size from 1/4 to 1/2 inch long. This type of insect has one node and a smooth, round thorax when viewed from the side. Carpenter ants hollow out wood to create nests. They can cause considerable damage to your home if not eradicated quickly.
Look for a tiny size -- approximately 1/32 of an inch -- and a yellow to light brown body when identifying thief ants. They have very small eyes on the head, an unevenly shaped thorax and two nodes on the petiole.