Facts About Drugstore Beetles

Drugstore beetles, Stegobium paniceum (Coleoptera: Anobiidae), are cylindrical, 1/10 to 1/7 inch long, and are a uniform brown to reddish brown. They have longitudinal rows of fine hairs on the elytra (wing covers). Drugstore beetles are similar in appearance to the cigarette beetle; however, two physical characters can be used to tell the difference between them. The antennae of the cigarette beetle are serrated (like a series of teeth on a saw) while the antennae of the drugstore beetle end in a 3-segmented club, with the last 3 segments larger and almost swollen like. The other difference is that the elytra (hard wing coverings that make up the beetle’s “shell”) of the drugstore beetle have rows of pits giving them a striated (lined) appearance while those of the cigarette beetle are smooth with fine hairs. Drugstore beetle larvae are small, white grubs; the later instars are scarab-like (think of grubs). They are similar to cigarette beetle larvae but have shorter hairs. Also, drugstore beetle larvae have markings on its head that ends in a straight line across the front of the “face” of the larvae, just above its mouthparts.