Facts, Identification & Control
The drugstore beetle is a small insect. The adult is about 2 to 3.5 mm long. It is oval-shaped and brown in color. Viewed from above, the head is not visible, so the beetle appears to be “humped.” The wing covers are lined with parallel rows of deep pits or punctures. The adult beetles can fly, and they are attracted to light.
Behavior, Diet & Habits
The drugstore beetle, Stegobium paniceum (L.), is a pest of stored products. The scientific name, paniceum, comes from the Latin word for bread. Some people suspect that the drugstore beetle’s common name came from its tendency to infest the herbs that early druggists used as medicine.
The drugstore beetle infests many food materials, including flour, cereal and spices. It also infests many nonfood products, including books and manuscripts, fur, leather and horn. Drugstore beetles have even been found in products that are poisonous like strychnine. Because they can infest such a variety of materials, these beetles can become a problem in more than one part of a home.
The adult beetle lays eggs on the food. When the larva hatches, it eats and grows. The larva stage lasts for several months. The full-grown larva spins a silken cocoon. Inside the cocoon, it takes more than two weeks for the larva to change to an adult. In a warm climate, the beetles can produce as many as four generations per year.
Signs of a Drugstore Beetle Infestation
Signs of drugstore beetle are the adults seen buzzing around or resting on surfaces. Other signs include holes in packaging where the beetles have emerged and debris deposited next to infested items as the larvae feed.
Homeowners often discover adult beetles in the pantry or near the kitchen windows. Controlling drugstore beetles begins with a thorough inspection. It is important to find everything that the beetles have infested.
In the kitchen, throw away any infested food. Clean pantry and cabinet shelves with a vacuum. Insecticide application is the final step. It should be applied only in cracks and crevices. The object is to help eliminate any beetles that may be hiding without contaminating surfaces. Incomplete treatment can allow survivors to re-infest. It is advisable to call a pest control professional to do these treatments.
It can be difficult to find infestations in other parts of the home. A flashlight will help with the inspection.