Perils of Swarming

Right on cue the Solenopsis xyloni have been swarming in Phoenix.

At eight in the morning, the new queens are climbing up grass stalks and leaves.

Any idea why the worker ants are standing on and huddled around the queens?

I’ll give you a hint.

You might be able to spot two of the reasons near the center line in this blurry photograph.

I’m afraid this is the best shot I got of the aerial assault by phorid flies.

Phorid flies of the genus Pseudacteon are known to attack fire ants. They are commonly called ant-decapitating flies for the fact that the infested ant’s head falls off during the final stages of the fly’s development. Each fly lays her eggs into the adult ants. The fly larva hatches from the egg, and feeds within the ant’s alitrunk. Once the larva is ready to pupate, the ant dies and literally loses its head. The larva pupates in the cozy head, and eventually emerges as an adult fly to attack more fire ants.

Photograph from Wikimedia

There was a small cloud of the flies attracted to the activity of the ants. These phorids seemed to particularly target the reproductives, although other phorids I have read about target workers.

To give you an idea how small and fast these flies are, check the area around the beige leaf in the lower right corner of the second part of this video.

Have you ever seen phorid flies around swarming ants? If so, what species of ants?

Ant Queens and New Colonies

When I am acting as the “Consult-Ant” and answering questions about ant farms, people are generally interested in finding out more about ant queens.

When an ant colony is ready to branch out, the current queen lays eggs that develop into males or new queens instead of workers. Adult male ants are winged, and have small heads and slender bodies. They can easily be mistaken for wasps.


Newly emerged queens are larger than both males and workers, and have four wings.


When conditions are just right, such as after a summer thundershower, the males and new queens fly from the nest. The whole colony is in a tizzy when this happens. Worker ants gush from the nest entrance and mill around. Winged males and queens climb up on grass stalks, trees, or anything tall in the area.


In many species, the winged queens and males fly to meet with males and queens of the same species of ant from other nests. They enter what is called a mating swarm, a swirling cloud of flying and mating insects.

After mating, the males drop to the ground and soon die. The new queens, the ones that escape being eaten that is, also drop to the ground. The queens quickly pull off their wings by rubbing them between the back of their body and their hind legs, twisting and tugging. Once the wings are off, they quickly hide themselves. Ground-nesting ant queens tunnel into the soil while other types of queens may slip into cracks in the bark of logs or creep under nearby rocks. There a queen makes a safe chamber to start her new colony.


You can tell she’s a queen because of the scars on her trunk (middle section) where her wings were.

The queen will lay eggs that develop into tiny worker ants, and a new colony is born.

Have you ever seen swarming ants?

The theme today for Life Photo Meme at Adventures of a Free Range Urban Primate blog is “reproduction.”