Foreign grain beetle
Ahasverus advena (Waltl)


Secondary pest: fungus feeder
Order: Coleoptera
Family: Silvanidae
Acronym: AAD


  • Foreign grain beetle is a small brown beetle, about 2 mm in length. It is superficially similar to the rusty grain beetle.
  • Larvae are very small and are whitish to yellow in colour.
  • Adults are able to climb glass walls of jars, unlike Cryptolestes spp.

Similar insects

Commodities affected

  • Grain, cereal products, oilseeds, dried fruit, herbs, spices

Signs of Infestation

  • Heated, damp grain with mould present


  • Grain injury is generally not sufficient to cause economic losses.
  • Contamination by insect is an issue.
  • Presence of beetles is an indication of out of condition grain or poor storage conditions.

How to control

Geographic range

  • Is found across Canada and throughout the world
  • Is the most common fungus grain beetle found in the prairie provinces

Where found

  • Is found in mills, warehouses and granaries and is an indication of mouldy grain and moist storage conditions
  • Is frequently present in the field at harvest and is subsequently transferred into bins

Life history

  • Females lay eggs singly, occasionally lay them in clusters of 2 or 3
  • Larvae form chambers of food particles cemented together


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Did you know?

The foreign grain beetle is found in both tropical and temperate regions.