The common scorpion fly undergoes complete metamorphosis. This includes egg, larval, pupal, and adult stages. Usually there is one generation per year.
Adult flies mate in summer after a unique courtship. Females lay 30 to 50 small eggs in moist soil. This is also where the larvae live, eat, molt, rest, and finally pupate
Larvae act as scavengers; they feed on dead plant and animal remains in the soil. Pupation also occurs in the soil. This is where they overwinter.
Scorpion flies are on the wing between May and September. They are approximately 1.5 cm long with a wingspan of about 3 cm. They have two pairs of transparent wings with some dark spots. The body is yellow and black. The specimen in my photograph is a female.