The egg of the thief ant is a small pearl white color surface, however it changes colors before the egg hatches (McColloch & Hayes, 1916). The Thief ants are small in size and the egg is about 0.25mm long. Queens usually lay around 105 eggs. When the queens lay the fertilized eggs, the workers take care for them. The workers or the queen must attend the eggs in order to hatch (Hayes, 1920). Workers regurgitate food such as seeds and place it in front of larvae to feed them (Hayes, 1920). The maturation and development of an egg can take anywhere from a few weeks to a couple months. The incubation period is about 16 to 28 days. Thief ants have four developmental stages before they become an adult. These include the egg, larva, pupa, and imago stages (Hayes, 1920). The larval stage is about 21 days, however it varies based on weather (Hayes, 1920). The female pupae are bigger than the worker and male pupae (Hayes, 1920).  Most eggs hatch during the summer, however the larvae can live through the cold winter months (Hayes, 1920). Females usually start mating in June but can mate all the way through the fall months (Smith M.R. 1965). Virgin females have wings, but lose them when they become fertile (Hayes, 1920).