Foreign grain beetle

Scientific name

Ahasverus advena (Waltl)

Classification

Secondary pest; Fungus feeder
Order: Coleoptera
Family: Silvanidae
Acronym: AAD

Description

• 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 species

• Rusty grain beetle (Cryptolestes ferrugineus).
• Foreign grain beetle can be distinguished from the rusty grain beetle by the presence of clubbed antennae and projections on the front edge of the pronotum (also called nubs and clubs)
• Flat grain beetle (Cryptolestes pusillus)
• Flour mill beetle (Cryptolestes turcicus)
• Sawtoothed grain beetle (Oryzaephilus surinamensis)
• Merchant grain beetle (Oryzaephilus mercator)
• Long headed flour beetle (Latheticus oryzae)
• Smalleyed flour beetle (Palorus ratzeburgii)
• Hairy fungus beetle (Typhaea stercorea)

Commodities affected

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

Signs of infestation

• Heated, damp grain with mould present

Damage

• 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

• Control grain insect pests

Geographic range

• Is found across Canada and throughout the world
• Is the most common fungus grain beetle found in the prairie provinces
• The foreign grain beetle is found in both tropical and temperate regions.

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