Ants live in colonies and are considered social insects. As social insects, ants divide colony labor, two or more generations of ants overlap and adultworkers care for the young or immature stages (and sometimes the immature stages serve to feed the adult workers). They have three distinct castes: adult workers (actually sterile female forms), reproductive males and reproductive females. Some species have only one queen, others may have many.

Ants undergo complete or holometabolous metamorphosis and have four life stages: egg, larva, pupa and adult.


Normally, only adult worker ants are seen, as these are the foragers (and defenders) of the colony. Ants are predominant insect predators and scavengers. Of the approximately 700 species found in the United States, around forty species are considered economically important, as pests. They have come to be the number one pest in the U.S., gaining entry into residences, commercial, and industrial structures.

They are members of the Order Hymenoptera and Family Formicidae (the venom of those ant species that sting contains formic acid). Ants are further divided into subfamilies for classification. This division is made according to variety of characteristics. Between the thorax and the abdomen is found the petiole, made up of one or two segments, called nodes. These nodes, and other morphological characters are used to differentiate subfamilies as well as species.


There are three major subfamilies of ants in Texas. They are the Myrmicinae, the Formicinae, and the Dolichoderinae. There is also a noted minor subfamily, the Pseudomyrmicinae.

  • Myrmicinae: Two node petiole
  • Formicinae: One node petiole, with a circular fringe of hairs at tip of abdomen, or gaster
  • Dolichoderinae: One node petiole, without a circular ring of hairs at tip of abdomen, or gaster
  • Pseudomyrmicinae: Acacia, or Elongate Twig ants have two nodes, head and body without sharp spines, slender body, and very large eyes. Myrmicinae