**Doodlebugs** is the common name given to the larval stage of **Antlions** (family Myrmeleontidae). Antlions are insects whose larvae are famous for digging conical, funnel-shaped pits in dry, dusty soil to trap passing ants or other small insects. The adult Antlion is a delicate, clumsy, flying insect resembling a damselfly. The larvae are considered beneficial natural enemies, while the adults are harmless.
Taxonomy and Classification
Antlions (and thus Doodlebugs) belong to the family Myrmeleontidae in the order Neuroptera (net-winged insects), which also includes lacewings and owlflies. They undergo complete metamorphosis. The larval stage is long-lived and the aggressive, predatory phase, while the adult stage is short-lived and focused on reproduction.
Physical Description
The **Doodlebug larva** is the iconic stage: a stout, hump-backed, oval-shaped insect, typically brownish-gray, with a rough, bristly body. Its most striking feature is its enormous, sickle-shaped, hollow mandibles, which it uses to seize and suck the fluids from its prey. It grows up to $1/2$ inch long and moves awkwardly, often backwards.
The **adult Antlion** is much less recognizable: a slender, soft-bodied insect with two pairs of long, translucent, heavily-veined wings and long, clubbed antennae. They are weak flyers and often mistaken for dragonflies or damselflies.
Distribution and Habitat
Antlions are found globally, especially in warm, sandy regions. The Doodlebug larvae require a specific habitat: dry, loose, fine soil or sand, preferably sheltered from rain and wind, such as under eaves, porches, or dusty outbuildings. This environment allows them to construct and maintain their characteristic trap pits.
Behavior and Life Cycle
The larval stage can last 1–3 years, depending on food availability. The **pit-digging behavior** is unique: the Doodlebug walks backward in a spiral, flicking sand and soil outward with its head and mandibles until a conical pit is formed. It then buries itself at the bottom, leaving only its mandibles exposed.
When an ant or small insect falls into the pit, the steep, loose sides prevent escape. If the prey tries to climb out, the Doodlebug aggressively tosses sand at it, knocking it back down. Once the prey is caught, the larva pulls it under the sand, injects enzymes to liquefy its insides, and sucks out the fluids. It pupates in a spherical cocoon covered in sand, and the short-lived adult emerges for mating.
Feeding and Ecological Role
Doodlebugs are highly effective predators of small ground-dwelling insects, making them beneficial natural controls. Their primary prey is ants, but they will capture any arthropod that falls into their traps. Adults may feed on pollen or be non-feeding. They are not pests and pose no threat to humans, pets, or plants.
Management and Prevention
Doodlebugs are harmless and beneficial, requiring no management. They should be protected. If found, they can be safely observed. Children often enjoy using a blade of grass or twig to gently “doodle” or trace around the pit’s edge, causing the larva to emerge—a behavior that inspired their common name.
Conservation and Research
Antlions are ecologically valuable. Research often focuses on the physics of their pit construction, their foraging strategies, and their use in behavioral and ecological studies as models for ambush predation.