ant death due to mass stinging of this species.
This species is practically omnivorous feeding on a variety of materials including honeydew, meat, seeds, fruit, nuts, cereal and cereal products, grease and butter and dead and living insects. It can be quite detrimental to agriculture foraging for seeds from seed beds, girdling nursery stock, and consuming fruits and vegetables. In addition these ants will remove insulation from wiring and occasionally gnaws on a variety of fabrics.
Fire Ant. The fire ant, Solenopsis geminata, is a native species sometimes called the tropical fire ant. It ranges from South Carolina to Florida and west to Texas. It is very similar to the southern fire ant except its head is much larger and the petiole node is higher and narrower. This species usually nests in mounds constructed around clumps of vegetation, but may also nest under objects or in rotting wood.
Red Imported Fire Ant. The red and black imported fire ants were first reported in the United States in 1929. It is thought that they came to the port in some soil used as ballast in the bottom of a cargo ship. Since this introduction the black fire ant has not spread as rapidly as the red imported species. By 1953 (first official USDA survey) the red imported fire ant had spread to over 100 counties in 10 states. Today it is prevalent throughout the southeastern US and has moved into Texas, New Mexico. Arizona and California.
Natural movement of fire ants is limited to mating flight or by rafting during period of flooding. However, the rapid movement of these species across the South and westward is mainly associated with human activity. In this case the initial spread of these ants in the southeastern US was thought to be due to movement of sod and potted ornamental plants. This inadvertent movement of S. invicta and S. richteri was noted by the U.S. Department of Agriculture in 1953 when a direct link was established between commercial plant nurseries and the spread of imported fire ants. In response to mounting public pressure, the U.S. Congress appropriated $2.4 million in 1957 for control and eradication efforts. As part of an overall plan quarantine was imposed to retard or prevent the artificial dissemination of these now notorious pests. On May 6th 1958, regulations governing the movement of nursery stock, grass sod and some other items were instituted through the Federal Quarantine 301.81. By that time, however, imported fire ants had moved into 8 southern states. This spread, although slowed considerably by federal regulations and climatic conditions, continues even today. In recent years, isolated infestations of imported fire ants have been found as far west as New Mexico, Arizona California and as far north as Kansas and Maryland. In the case of California it is thought that the spread of these ants into this state was due to movement of bee hives as most initial infestations were found in around orchards and other situations where bees were moved into these areas for crop pollination. Based on USDA prediction these ants have a potential of even expanding the spread throughout much of the United States.
Current and potential distribution of imported red fire ant. Image courtesy of USDA.
Adult fire ants (Genus Solenopisis) are characterized by the presence of a ten-segmented antennae, two-segmented antennal club and two-segmented waste that joins the thorax to the abdomen which is typically darker than the rest of the body. Species identification is somewhat more difficult due to hybridization between the 2 "native" species as well as between the 2 imported species.
Diagram of diagnostic characteristics of red imported fire ant.
A mature colony of fire ants typically consists of 4 main stages: egg, larva, pupa, and adults. Since these are true social insect there is a caste system with different shaped and sized adults that carry out different function within the colony. These adult forms include the polymorphic workers, winged males, winged females and one or more reproductive queens. The egg, larval, and pupal stages (Fig