Life Stages of a Scorpion Fly

Scorpion flies lay their eggs in the soil. The specific timing varies, but adults generally lay their eggs in the spring. In the southernmost parts of their range in the United States, adults may lay their eggs as early as February, but generally it happens later in the year as temperatures get warmer. The eggs usually hatch throughout the spring and summer, but this depends on the exact species and local weather conditions.

Once the egg hatches, scorpion fly larvae emerge. The larvae resemble caterpillars. This life stage is equivalent to the caterpillar stage of a butterfly's life cycle. Less glamorously, in houseflies the same life stage is the maggot. Scorpion fly larvae keep themselves buried in the soil, avoiding predation above the soil. Like adults, they are omnivores and eat dead animals, especially insects, as well as plant material.

After the larva stage, a scorpion fly enter a stage called the pupa. Some insects, such as moths and butterflies, form cocoons and chrysalises during this stage to protect the pupae, since they cannot move. However, scorpion flies do not form cocoons. Instead, the larvae create cells out of soil to protect them during the pupae stage. They remain hidden in the soil. During the pupa stage, scorpion flies remain immobile and don't eat, transforming themselves from caterpillar-like larvae into adult flies. During this transition, the pupae live off energy they stored during their larval stage.

Adult flies emerge in late fall or early winter, though the exact timing varies by species and location. As omnivorous scavengers, they feed on dead organisms, most often insects. To court females, males perform an elaborate dance. In some species, the male gives the female a dead insect. Some males have adapted to imitate females to get a free meal, which they either eat or "regift" to females in their own bids to reproduce.