The old endocuticle is digested, absorbed, and secreted as new procuticle. The new procuticle forms before ecdysis. The new exocuticle forms after ecdysis. The new epicuticle forms before ecdysis. The old exocuticle is shed and tanning occurs during ecdysis.
Wireworms are elateriform larvae.
They have not yet begun to develop. They are still in their undifferentiated embryological state. The exuvium is the remains of the old exoskeleton after an insect has molted.