Warehouse Beetle Identification
Trogoderma variabile
The Warehouse Beetle is a common stored product insect in commercial food processing, pet food, and grain facilities. It is frequently associated with seeds, animal feed, nuts, and grain-based ingredients.
Quick Identification
- Adults: Dark brown with lighter reddish bands, 2–4.5 mm long
- Adults can fly
- Larvae: White to tan with dense hair tufts
- Shed larval skins often present in infested product
Where We See It
- Ingredient storage areas
- Pet food plants
- Warehouses and distribution centers
- Seed and feed facilities
Life Cycle
- Females lay ~100 eggs
- Development slows below 64°F
- Optimal development: ~90°F at 70% RH
- Populations increase rapidly in warm conditions
Why It Matters
- Larvae chew into seeds and kernels
- Contamination from shed skins and hairs
- Can trigger allergic reactions
- Difficult to control once established in hidden voids
Monitoring & Control
Sanitation and removal of infested product are critical. Because larvae hide in cracks and structural voids, fumigation may be necessary for complete elimination in commercial facilities.
Need Help Identifying This Pest?
FSS stored product entomologists can confirm identification through photo review or laboratory analysis, then recommend a facility-specific plan.