Adult female antlions lay eggs singly in sandy or loose soil. When the egg hatches, the larva digs a conical pit and hides just below the surface at the bottom. When an ant or small insect falls into the pit, the antlion grabs its prey with its jaws (mandibles), pierces its body, and drags it below the surface. The hollow barbs or spurs on the jaws can both inject and suck. They inject poison to immobilize their prey and enzymes to break down the internal tissues. When the antlion finishes sucking the juices out of its prey, it will cast the insect out of the pit and wait for the next one. I found a couple of shriveled-up ants on the top of one of the cones.
Along some of the paths at the Arboretum, you will find these pits, usually protected under the canopy of trees. I have often seen these pits in soil under the eave of a house or barn where it is sheltered and stays dry.
When the larvae are ready to become adults, they dig deeper into the soil and form a round cocoon made of sand and silk. After about a month, the insect emerges as an adult to mate and repeat the cycle. The adult has a long, skinny abdomen with four narrow, veined wings and resembles a damselfly. The antlion is differentiated from a damselfly by its prominent clubbed or curved antennae. Also, the antlion rests its wings back in an A-frame fashion, and a damselfly holds them together. I have been looking around to find one to photograph, but I haven’t found one yet.
To find the antlion larva, I took a spoon and scooped the ground underneath and around the pit. I didn’t want to hurt it or have it retreat into the soil if I tried to extract it directly from the pit. I put the scoop in a little sieve and gently sifted out the dirt. I was left with tiny stones, flecks of wood, and other debris. It took me a minute to locate the antlion larva because it blended in so well with this assortment of organic matter. I gently moved it onto a leaf and then onto the ground. I was surprised by how cooperative it was in being handled and photographed. I sat beside it and watched it, hoping to see it make its pit. After about 10 to 15 minutes, it slowly retreated to slightly below the surface. I waited for a little longer, but it didn’t move. I marked the spot and returned the next day to find that it had remade its pit and was waiting at the bottom. I love this insect! I hope to see you out there.
Antlion. https://texasinsects.tamu.edu/neuroptera/antlion/. Accessed 11 Oct. 2023.
“Antlion Adults.” Missouri Department of Conservation, https://mdc.mo.gov/discover-nature/field-guide/antlion-adults. Accessed 11 Oct. 2023.
Antlions | Nebraska Extension in Lancaster County. https://lancaster.unl.edu/pest/resources/antlions.shtml. Accessed 11 Oct. 2023.