Texas Cooperative Extension Harris County

Fire Ant Pic What Kind of Ant is This?*

Lisa Lennon, Extension Agent - IPM.(Fire Ant Project) for Travis and Williamson Counties, the Texas AgriLife Extension Service

Ants are not all created equal. There are many species in Texas and it just takes some persistence and knowing what to look for to tell them apart. Most people think that only fire ants are around. But if you look closely and take time to learn a little ant biology, the ant world can be a captivating place to be. Red imported fire ants are real pests, with few natural enemies in the United States. Many other ants live here too, but most are not considered pests. In fact, many native ants are in constant competition with the imported fire ants and may even help humans in the war against this invading species.

Ants that compete with fire ants are sometimes difficult to identify, but once their characteristics and habitats are revealed, most are easy to spot - and perhaps even use them to our advantage against imported fire ants. Described below are some common desirable or competitor ant species, how to identify them, what their nest looks like, where they live, and what they eat:

PYRAMID ANT Dorymyrmex spp.: A small ant about 1/8" long. Key identifying feature is a pyramid-shaped projection on top of the thorax. They are red-black or dark brown. It builds its nests in open, sunny areas. The workers deposit the soil in a circular crater or mound around the entrance hole and are usually 2 to 4 inches in diameter. These mounds are usually located near the nests of other ants, particularly harvester ants. The colonies can also be found under decorative rocks and logs. Workers move quickly and forage in ready trails. They feed on other insects and are fond of the honeydew produced by aphids and scales.

LITTLE BLACK ANT Monomorium minimum: A very small, black ant and closely related to the Pharaoh ant (an indoor pest ant). It nests in soil under rocks, logs, or debris. It will also build nests in open areas of soil in lawns. The nests in the ground are small craters of very fine soil. Their colonies will also be found under the bark of trees, in debris trapped in the crotches of trees, and in wood damaged by termites, in firewood piles and in stacks of bricks and stones. Little black ants feed on a wide variety of foods including live and dead insects, and the honeydew produced by aphids. The ants are active foragers and forage in trails of a few or up to hundreds of workers. These trails can be located along sidewalks and foundations and up the sides of buildings.

CRAZY ANT Paratrechina longicornis: Small, dark grey to black ants, that are easily recognized by their extremely long legs and antennae. Crazy ants get their name from their habit of running about very erratically with no apparent sense of direction. Colonies can most often be found living in soil, under items such as logs, stones, landscape timbers, wood, debris, and living under above-ground swimming pools. Crazy ants feed on a wide variety of foods, including other insects, grease, and sweets. They have been known to feed on the larvae of fleas and flies, and also have been observed carrying away fire ant queens immediately following a swarm.

BIG-HEADED ANT Pheidole spp.: Big headed ants have two sizes workers– major workers (soldiers) and minor workers. Major workers have a very large head in proportion to their bodies. Big headed ants are most often confused with fire ants, but imported fire ants do not have workers with larger heads. Big-headed ants usually nest in the soil in protected locations such as under rocks, logs, firewood, patio blocks and landscape timbers, although they will nest in open areas of soil. They typically feed on live and dead insects, seeds and the honeydew produced by insects such as aphids and scales. They are considered major predators of fire ant queens which are present in large numbers following a fire ant swarm.

For more information about ant identification, visit the fire ant web site at: http://fireant.tamu.edu., look for fact sheet, FAPFS#010, for the illustrated key or the slides under "materials" and "images".

* Information taken from Structure Infesting Ants by Stoy A. Hedges

For more information contact:

Paul Nester
Extension Agent - IPM
Fire Ant Project
Harris County
Phone: (281) 855-5600

or visit http://fireant.tamu.edu.

the Texas AgriLife Extension Service - Harris County

the Texas AgriLife Extension Service-Harris County