Flat grain beetle
Cryptolestes pusillus (Schönherr)
Primary pest; grain feeder
- 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.
- 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 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
- Is distributed worldwide, but is more common in wet-tropical and warm-temperate regions
- Is found in Canada from Quebec west to British Columbia
- 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
- 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.
Not what you're looking for?
Start over again from the insect identification keys page.
- Date modified: