Indian Meal Moth (Plodia interpunctella)
The Indian meal moth (Plodia interpunctella) is the most common household moth that can reproduce in many homes. It develops as a pest of various foods commonly found in pantries. The caterpillars or larvae can seriously damage susceptible food items and the adult moths can become annoying as they fly through the home. They are a common grain-feeding pest found around the world, feeding on cereals and similar products.
General Biology
All stages of the Indian meal moth may be found in homes. The adult is a small moth, about 3/8 inch long with a wing span of about 5/8 inch. The overall body color is generally dirty gray but the tip half of the wing is rusty brown or nearly bronze. The moth larvae are off-white with brown heads. The entire life cycle of this species may take 30 to 300 days. Female moths lay between 60 and 400 eggs on a food surface, which are ordinarily smaller than 0.5 mm and not sticky. The eggs hatch in 2 to 14 days. The larval stage lasts from 2 to 41 weeks, depending on the temperature, which makes this insect very problematic in homes. The adults emerge, mate and lay eggs. Since the moths do not feed they usually survive little more than a week. During this time the female may deposit over 200 eggs, laid either directly on food or in crevices adjacent to the stored foods on which they feed.
Control
The first step is to identify all sources of infestation. The presence of some webbing is usually the most effective way to determine which items are infested. After larvae or moths have been found, it is important to throw out all food sources that are not in very tightly sealed containers. The moths are able to get into surprisingly tight spots, including sealed bags and Tupperware containers. Nontoxic traps are also available to inhibit the development of adult moths and precipitate their destruction. Moths often do not even need a lure, as common glue traps sometimes work well to reduce the number of adults.