Darkling beetle

The mealworms I bought earlier in the year are turning into pupae. The pupae is on the right and does not feed. It takes 2-3 months to change into a beetle. At the top is a mealworm half way through the change. To the left is a mealworm. The mealworms shed their skins many times and take months to grow from the egg to the pupae stage. They feed on oats or wheatmeal. The adult beetles feed on mostly decaying leaves and plants with some green stuff too.