Leafcutter Ant Mound and Antlions

The leafcutter ants were busy in Tucson a few weeks ago.

Check out this mound the ants had constructed.

Most of the workers I saw were carrying clumps of dirt/pebbles.

The worker dumped her load and then went back for more.

The surface of the mound looks like a boulder field from the perspective of the ant.

Harvester ants and other types ants also have pebbles on the surface of their mounds. (Harvester ants decorate their mounds with other things as well.)

A curious docent wondered why I was taking photographs of the ants. After wishing the mound was in the sun, she volunteered to show me another mound she knew of that she thought might be in the sunlight.

Turns out it wasn’t in the sun, but there was something else there.

You see those cords? A crew that was stringing Christmas lights had trampled the leafcutters’ mound. I’m not sure whether the ants simply reverted to another entrance or whether they abandoned the nest.

I was intrigued to see those circles though. Do you know what they are?

Those are pits made by larval antlions (See previous post about antlions.)

Antlions seem to prefer fine, powdery soil (The Antlion Pit).

So, do you think perhaps ants may decorate their mounds with pebbles in an effort to keep down antlions, as well as other species of ants as has been suggested? Do you know of anyone who has studied this possibility?


People usually notice antlions when they see their pits in the soil.

The cone-shaped holes are fascinating. Kids big and small like to put objects into the pit to elicit a response from the larva buried at the bottom. You have to wonder how the larvae flip the soil with such accuracy when they are buried beneath it.

You don’t see the adults as often.

The adult antlion somewhat resembles a damselfly, but they are actually more closely related to lacewings (Order Neuroptera).

These were hanging around the buildings at a highway rest stop. Presumably they had been attracted to the lights at night.

Hard to imagine this delicate beauty comes from the larva you see in this video. Note: the video contains scenes of violence to ants.

For more information, see this previous post about antlions.

Poll question:  Do you think the common name should be ant lion (2 words) or antlion?

Ant Lions

We’ve been seeing a lot of ant lion pits lately.


The insect at the bottom of those funnel-shaped pits is the larval stage of the ant lion, also called a doodlebug. Ant lions are found in warm areas throughout the world, including Florida and the southwestern United States.

The ant lion larva looks a bit like a lacewing larva, and the two are related. Here’s a photo of an ant lion larva from Iowa State University. Some species have even longer jaws.

The ant lion larva digs a pit in loose dirt or sand near ant colonies. We’ve had a particularly dry year and there is a lot of powdery dry soil, which the ant lions seem to prefer for constructing their pits.

When an ant or other small insect falls into the pit, the larva flicks sand or soil at it to knock it towards the bottom. Once the ant is within reach, the larva grabs it and drags it under the sand to eat it.

When the larva attains its full size, it pupates. The pupa is round and covered with a layer of silk. The adult ant lion emerges from the soil. It is slender with wings with many veins that fold back over its body when it is at rest. The adult might be mistaken for a damselfly or dragonfly. Firefly Forest has a fantastic photograph of an adult ant lion.

Edit: and now I have my own photographs of adults.