Metamorphosis of ant-lions takes place in a spherical cocoon of silk covered with grains of sand. After a period of about four weeks, the pupa uses its strong mandibles to bite a circular slit through the wall of the cocoon so that the top can be raised. Through the opening thus produced, the pupa emerges a little. The pupal skin splits along the back, and the imago starts to free itself. Initially, the appendages of the head and the legs are restrained inside the pupal skin and it takes some time to pull them out. After entirely having freed itself, the imago seeks a raised twig or stalk to spread from the base outwards. A few minutes later, the wings are rotated into the normal position above the abdomen. Soon after emergence, solidified remains of the larval food are discharged by the imago as a reddish meconial pellet. This is because during larval life the stomach does not communicate with the hindgut. During the course of a few hours, the integument hardens, adult coloration is assumed, and the ant-lion is ready to fly.