When the worms first arrived, seven worms were placed in individual compartments so they would pupate. They must be totally isolated from each other for that process to begin. I gave them each a fresh piece of potato or carrot when I replenished the food for the general population, usually once every couple of days. You can tell when they are beginning to change when they curl themselves into a circle.
It takes them a few days to do this and they don’t all begin to pupate at the same time. Some of them shed their skins first, like snakes do. Then one day, you look to see an alien-like being has replaced the curled up, dead-looking worm. The cream colored pupa has some distinguishable features like legs, head and body. The pupae are removed to a separate container and another super worm is placed in the cell they vacated.
As they mature, the legs and eyes become darker and the beetle it will become is more discernible. The more advanced pupa in the picture below has darker legs. It will become a beetle in the next couple of days. It will be moved to yet another container so when it morphs it won’t feed on the less mature pupae.
The super worms arrived on 3/3/11 and we had our first Darkling Beetle on 4/3. It is about 1″ long which is longer than I expected it would be. There are a couple more pupae that look like they are ready to begin life as beetles very soon.
According the the booklet from Carolina Supply, Darkling beetles can live 3 months to one year. This is good news. You can keep a small breeding population of beetles and not be a slave to monitoring pupae. The beetles are moved to a fresh container every week to prevent them from feeding on the eggs they’ve laid in the bedding.