The Darkling Beetle (Tenebrio molitor) is the adult and final stage of the mealworm lifecycle. This harmless beetle is friendly, energetic, and makes an excellent model for insect anatomy with its 3 distinct body regions. Larva is 1/2 to 2″ long and does not readily pupate. The pupa can take 3 to 4 weeks to develop into an adult. Beetles and larvae are easy to care for – simply provide the Beetle People’s WormChow Blend. The Darkling Beetle is a holometabolic insect which means that it transitions through 4 life stages: egg, larvae (AKA mealworm), pupa, and adult Beetle. The mealworms feed for about 3 months and then transition into the pupae phase. After 7 to 14 days the adult Darkling Beetle emerges from its pupa. After maturity (turn black in color) the adults breed and the female starts producing eggs after about a week. It takes another week for the eggs to hatch into baby mealworms. Beetles will live for 3-5 months and produce several thousand eggs every few weeks.