Flat grain beetle

Classification

Primary pest; grain feeder
Order: Coleoptera
Family: Laemophloeidae
Acronym: CPU

Description

• Adults are small (1.5 to 2.0 mm), reddish brown and flattened with long bead-like antennae.
• Adults have a ridge (sublateral carina) on the head and prothorax.
• Larvae are elongate and flattened with well-developed legs.
• Larvae are pale, white to yellow in colour with a darkened head capsule and dark urogomphi present.
• Male antennae are longer (almost as long as body) than female antennae (half the length of the body); rusty grain beetle antennae are the same length in both sexes.

Similar species

• Rusty grain beetle (Cryptolestes ferrugineus)
• Flour grain beetle (Cryptolestes turcicus)
• Foreign grain bettle (Ahasverus advena)

Commodities affected

• Mainly damages grain, preferably wheat
• Will also feed on beans, bulbs, cacao, cereal products, citrus pulp, copra, cottonseed, cowpeas, maize, malt barley, filberts, nutmeg, rice, sorghum, soybeans, sunflower

Signs of infestation

• Damage is not readily identifiable as being caused by this species.

Damage

• Damage is usually restricted to grain stored under high moisture conditions.
• Both larvae and adults feed on germ and endosperm.
• Heavy infestations may cause grain to heat and spoil.
• Damage may spread fungal spores through grain.

How to control

• Control grain insect pests

Geographic range

• Is distributed worldwide, but is more common in wet-tropical and warm-temperate regions
• Is found in Canada from Quebec west to British Columbia

Where found

• Is found mainly in grain elevators and flour mills, warehouses, farm-stored grain
• Is often confused with the flour mill beetle (Cryptolestes turcicus)
• Is probably the least damaging species of Cryptolestes in Canada
• Can survive Canadian winters only in heated structures

Life history

• Females lay eggs in crevices or loosely amongst the food.
• Larvae move actively amongst the food feeding on the endosperm or germ Adults cannot climb up glass.