Adult antlions are much larger than their larvae and look like fragile, drab damselflies, with an elongated body, four intricately veined wings mottled with browns and black, and clubbed or curved antennae about as long as the combined head and thorax.
Larvae are oval, plump, flattened, soft-bodied, with segmented abdomens and 6 legs. They are mottled and dirt-colored, often with bristles. The head is flattened and bears a pair of large, sicklelike pincers that often have spines. Larvae in the genus Myrmeleon are most familiar. Though seldom seen, they live just beneath small, conical pits they create in sandy or loose soil. When they walk about on sandy surfaces, they leave behind meandering, scrawl-like patterns, hence the name “doodlebug.”
Adult length: 1½ to 3 inches (not including appendages; varies with species); larvae are much smaller than adults, reaching only about ½ inch.
Habitat and Conservation
Adult antlions fly soon after their wings harden and are best looked for during calm, late-summer sunsets and evenings, as they flutter about seeking mates and good places to lay eggs. They also come to lights. Larval antlions are found, often in groups, in areas of sandy soil. There, each digs a conical pit by creeping backward and downward, using its head to flip soil away in quick jerks. The antlion needs this sandy pit to hunt, so soil conditions must be just right for an effective trap.
Antlions spend only about a month, or a little longer, in their adult form, nourishing themselves with nectar and pollen. Most of their lives are spent in larval stages, being voracious predators of ants and other small insects. Waiting quietly at the bottom of its conical pit, with just the tips of its pincerlike fangs protruding, the antlion larva quickly grabs any ant or other insect unlucky enough to tumble down the sides of the sandy pit in a miniature landslide. The antlion snags the prey in its caliper-like jaws and drags it below the pit, where it drinks its juices. Then the antlion hurls the drained skin beyond the edges of the pit and waits again.
Adult female antlions lay eggs singly in sandy soil. These hatch into small larvae that dig pits in the soil, live just under the base of the pit, and eat voraciously, molting occasionally as they grow. When ready to become adults, they dig more deeply into the soil and begin a pupal stage within a round cocoon made of sand and silk. After about a month, the insect emerges as an adult, crawls aboveground, allows its wings to harden, and takes flight. The adult antlions mate and repeat the cycle.
Like spiders, praying mantises, lady beetles, and lacewings, antlions quietly provide people, and the rest of the earth, the service of natural, nontoxic insect control. They are fascinating to watch, and science fiction writers certainly draw inspiration from creatures like these.
The antlion’s name honors its role as a top predator in the miniature world of insects, where, to animals like ants, a patch of sandy soil is like a major sand dunes. The adult antlions, flimsy, fluttery creatures, race to mate and lay eggs before being eaten by birds, bats, and other fly eaters.