Owlflies are in the Order Neuroptera, family Ascalaphidae. Owlflies resemble a cross between a dragonfly and an adult antlion. They have slender bodies with clear wings and are easily recognized by their long clubbed antenna. Adult owlflies are aerial predators feeding on other insects. When disturbed, an owlfly will release a strong, musk-like, chemical to deter an enemy. Adults are most active at sunset and dawn and can often be collected around lights. During the day, adults rest on stems and twigs with the body, legs, and antennae pressed to the stem. The abdomen is held up, projecting into the air, to look like a broken twig. Most owlflies average about 2 inches in length. Adult Ululodes have large divided eyes which is where the common name Owlfly came from. Owlflies can be found in most areas of North America.
Owlflies lay eggs in groups, usually at the tips of twigs and limbs. Less than ¼ inch below the eggs, the owlfly creates a protective shield to prevent crawling predators from reaching the eggs. This shield resembles a twisting spiral of evenly spaced tiny stalks, that are a shiny rust-like color. Larvae hatch from their eggs and tend to cluster together for a few days for defensive purposes. During this time, the immature owl flies will eat small insects like fruit files, midges, etc. that happen to walk by the cluster. When contacted by other predators, they lift their heads high and quickly snap their long sickle-shaped jaws. Owlfly larvae will separate from the group and descend to the ground in about a week. Larval owlflies can reach 24mm in length. Once on the ground, they lead a solitary life and live in debris waiting to capture prey. Pupation occurs in silk cocoons that are built in the leaf litter debris that the larvae have lived in. Adults emerge to become strong fliers who feed on small insects.
Brooke Saad & Pickens Lindsey
Insect Biology and Diversity (ENT / BIOSC 301)
Fall 2004
