Larvae are about 9 mm long. Sweet potato, morning glory, and other plants of the same family. Larvae cause damage by burrowing through the stem and roots. Even slightly infested sweet potatoes are unfit for food. Heavily infested tubers are unfit even for stock feed.
Breeding is continuous throughout the winter, especially in potatoes in storage.
Eggs are laid singly in small cavities eaten out in the stem or tuber. Eggs hatch in less than a week and larvae feed inside for two to three weeks. Pupation occurs in the potatoes. The pupal stage lasts about a week to 10 days. There can be as many as eight generations per year.