Stegobium paniceum (Linnaeus)
Common name: Drugstore beetle, bread beetle, or biscuit beetle.
Geographical distribution: Cosmopolitan, more common in warmer regions.
Morphology: Body of larva is bent (C-shaped), about 6 mm long, white, covered with fine short hairs, head brown. Adults 3-4 mm long, uniformly brown-red, the head is bent downward, elytra smooth, striated, the antennae ending with three enlarged segments.
Host foods: Mnay dry food products, like flour, bread, chocolates and spices, also feeding on books and leather, meat and even insect collections.
Life cycle: The adults are strong fliers and live for about 3 weeks, laying about 75-100 eggs/female in the food substrate. Larval development may require several months, depending on the food sources and the temperature (the optimum is around 30°C). The fully grown larvae build a chamber consisting of food particles and pupate therein.
Economic importance: This pest causes much economic damage to stored grains and seeds, packaged food products, and animal and plant-derived products. It can also affect animal skins, books and their bindings and even plant collections. Glass has also been reported to be damaged.
Monitoring: The beetle can be detected by finding shot-like holes in the packaging of food items and by the presence of loose powder at the bottom of storage bags. Prior to infestation they may be attracted to sticky traps containing the female sex pheromone, stegobinone, and by traps with ultra-violet light.
Mechanical control: Discovering and removing the source of the infestation, which could be bulk items, like seeds or dry pet food. Vacuuming food storage areas such as cabinets, including spaces between floor boards. Foods should be stored in airtight containers, and open food or seed packages are to be discarded. Reducing the humidity in storage areas. Susceptible items can be preserved at or below -20ºC. Another option is heat treatment followed by cold storage, first exposing the pests to 42ºC for 30 hours and then kept them at below 18ºC. Insect collections can be kept free of the pest when maintaining temperatures of 13-17ºC.
Chemical control: Diatomaceous earth or Insect growth regulators (IGRs) may be spread in corners, cracks and crevices or mixed into bird seed. Chemical pesticides are little used due to the danger to humans and domestic animals.
Biological control: The pest is attacked by a variety of generalist natural enemies. Predators include Tenebriodes sp. (Tenebrionidae), Thaneroclerus sp. (Cleridae) and several carabids. Eggs may be eaten by predatory mites. Parasitoids include species in the families Pteromalidae, Eurytomidae and Bethylidae. However, biological control for stored-product pests has not been widely adopted because the presence of beneficial insects in the stores increases the total amount of unwanted insects and insect parts in foodstuffs.
Abdelghany, A., Awadalla, S.S., Abdel-Baky, N.F., EL-Syrafi, H.A. and Fields, P.G. 2010. The control of the drugstore beetle, Stegobium paniceum (Coleoptera: Anobiidae) with high and low temperatures. Proceedings of the 10th International Working Conference on Stored Product Protection, pp. 671-672.
Ignatowicz, S. Janczukowicz ,K. and Olejarski, J. 2001. Integrated Pest Management (IPM) of the drug store beetle, Stegobium paniceum (L.), a serious pest of old book. Entomological and Acarololical Research 43: 177-183.
Jones, R.A. 1997. Metal-eating by Stegobium paniceum (Linnaeus) (Coleoptera: Anobiidae). British Journal of Entomology and Natural History 10: 101.
Lefkovitch, L.P.1967. A laboratory study of Stegobium paniceum (L.) (Coleoptera: Anobiidae). Journal of Stored Product Research 3: 235–49.
Kodama, H., Ono, M., Kohno, M, and Ohnishi, A. 1987. Stegobiol, a new sex pheromone component of drugstore beetle (Stegobium paniceum L.). Journal of Chemical Ecology 13: 1871-1879.
Rumball, N. and Pinniger, D. 2003. Use of temperature to control an infestation of biscuit or drugstore beetle Stegobium paniceum (L.) (Coleoptera: Anobidae) in a large economic botany collection. Collection forum 18: 50-58.