The antlion larva moves deeper into the sand to build its cocoon. It extends its heavy abdomen lengthwise and from it, extrudes white silken threads which form a hollow sphere

Figure 1. The cocoon of an antlion (Myrmeleon sp.). © 2005 Mark Swanson

held in place by the surrounding sand. (Some of the larva's stored waste matter is used to produce this silk.)

Figure 2. An antlion adult (Myrmeleon sp.), recently emerged from its cocoon. © 2005 Mark Swanson

Inside this hollow sphere, it undergoes metamorphosis into a pupa. Near the end of the pupal stage, the antlion eliminates the rest of its accumulated feces in the form of a pellet called a meconium. After a pupation period of about three weeks, a tiny-winged imago (adult) emerges from the cocoon, leaving a small hatch at the opening (Figure 1), and climbs to the surface.

The adult antlion usually emerges from its cocoon in the evening. It is not yet able to fly, so it climbs up the nearest plant or tree where it waits for its wings to expand and harden (Figure 2). After about 20 minutes the adult's wings are fully formed. An adult antlion may eat small flies or water, but its real purpose now is reproduction, not feeding. Its remaining life lasts less than a month on average—enough time for it to mate and lay eggs.

Video: "Metamorphosis" (0:21)