I assume that you are talking about the adult beetles here. They can release a pungent smelling substance if they feel threatened. I've never had one do it. I don't believe the pupae have any defensive capabilities other than wiggling their bodies when picked up.BTW don't touch it, IT STINKS IF TOUCHED
They will pupate at room temperature in dry substrate. But unlike regular mealworms, they will only pupate if they are separated from other larvae.Don't these only hatch whenever its really hot and humid? Wondering what kind of T is in that enclosure.