The Indianmeal moth, Plodia interpunctella, is the most common stored product pest in homes, where it infests bird seed, breakfast cereals, and other consumables. Indianmeal moths are most commonly found infesting food items in kitchen cupboards, but adults may be found throughout the home because they are excellent fliers and readily disperse from the food item they are infesting. Adults may be found away from the larval food source.
Adult Indianmeal moths are distinctive in appearance. Their wings are bicolored and alternate between beige and copper (Figure 1A). Moths are most active at dusk, when they can be seen (indoors) flying while searching for mates and food. During the day, moths can be found resting motionless on walls and ceilings, often near their larval food source. Adults are short-lived and do not feed.
Indianmeal moth larvae, just before they pupate, are approximately 5/8 inch long, cylindrical, and a dirty white to faint pink or green color (Figure 1B). Larvae produce visible silk webbing in the items they infest (Figure 1C) and generally pupate close to the items they are infesting. Just before pupation, larvae crawl away from their feeding site to pupate at the intersection of a ceiling and wall or similar seam within the cupboard, including spaces between walls and shelves and in the tight folds of packaging. Another favorite pupation site is in the corrugation of cardboard boxes. When looking for Indianmeal moths, inspectors should lift the liner out of the cardboard box to check beneath it.