Dark/Yellow Mealworms
Tenebrio spp.
Top: Dark mealworm (Clemson University, Bugwood.org) Bottom: Dark mealworm adult (Pest and Diseases Image Library, Bugwood.org)
Top: Yellow mealworm adult; Bottom: Yellow mealworm (Clemson University, Bugwood.org)
Identification
Dark mealworm
- adult: dull black or very dark brown
- larvae: up to 1 1/4 inches long, smooth, cylindrical and brownish to dark yellow
Yellow mealworm
- adult: shiny black to dark brown
- larvae: up to 1 1/4 inches long; smooth, cylindrical and golden-yellow
Nesting Habits
- lay eggs singly or in clusters in food sources
- prefer dark, damp and undisturbed environments
- larvae can migrate from infested areas
Diet
- old or moldy grain, oats or seeds
Significance
- presence indicates a lack of proper sanitation
- eggs and/or larvae ingested with breakfast foods can cause gastrointestinal discomfort
IPM Recommendations
- Improve sanitation procedures in affected areas.
- Inspect all incoming food items for pests.
- Store food items in pest-proof containers.
- Dispose of infested food items.
- Keep moisture low in food storage areas by improving ventilation.
- Keep food in regular rotation.