The Bean Weevil (Acanthoscelides obtectus) is a member of the family Chrysomelidae (seed beetles or bruchids) and is one of the most important pests of stored dry beans, lentils, chickpeas, and other legumes worldwide. Despite the common name 'weevil,' it is not a true weevil (family Curculionidae) and lacks the elongated snout characteristic of true weevils. Adults are small (1/8 inch), oval, grayish-brown to olive-brown with a mottled pattern of gray, brown, and black scales on the wing covers. The abdomen tip is exposed beyond the wing covers. Adults can fly and are attracted to light. Like true grain weevils, the Bean Weevil is a primary pest — females lay eggs on or in bean seeds, and larvae bore inside and develop entirely within the seed, consuming the contents. Multiple larvae can develop in a single large bean. Adults emerge by chewing round exit holes through the seed coat. In Arizona, the Bean Weevil is a common pest of stored pinto beans, black beans, kidney beans, lentils, and chickpeas. Infestations are often introduced through already-infested beans purchased from stores. In Arizona's warm climate, it can complete a generation in 3–4 weeks.
👁Warning Signs
Small (1/8 inch) mottled grayish-brown oval beetles found in stored dry beans, lentils, or chickpeas. Round exit holes in bean seeds. Hollow, empty bean seeds. Fine powdery frass in bean storage. Adults may be found flying near bean storage.
⚠Health & Property Risks
Destroys dry beans, lentils, and legumes from the inside. Multiple larvae can develop in a single bean. Rapid reproduction in Arizona's warm climate. Infestations often introduced through purchased beans.
Prevention Tips
Store dry beans and lentils in airtight containers. Inspect purchased beans. Freeze new bean purchases for 1 week to kill eggs and larvae. Rotate bean stocks regularly.
🛡Professional Treatment
Discard all infested beans. Freeze suspect beans at 0°F for 1 week. Airtight storage for remaining beans. Clean and vacuum storage containers.
Frequently Asked Questions — Bean Weevil
The Bean Weevil (Acanthoscelides obtectus) is grayish-brown to olive-brown with mottled pattern of gray, brown, and black scales and typically measures 1/8 inch; oval; abdomen tip exposed beyond wing covers. The Bean Weevil (Acanthoscelides obtectus) is a member of the family Chrysomelidae (seed beetles or bruchids) and is one of the most important pests of stored dry beans, lentils, chickpeas, and other.
The Bean Weevil poses a moderate risk. Destroys dry beans, lentils, and legumes from the inside. Multiple larvae can develop in a single bean. Rapid reproduction in Arizona's warm climate. Infestations often introduced through purchased beans.
In Arizona, bean weevils are most often encountered in the following situations: Small (1/8 inch) mottled grayish-brown oval beetles found in stored dry beans, lentils, or chickpeas. Round exit holes in bean seeds. Hollow, empty bean seeds. Fine powdery frass in bean storage. Adults may be found flying near bean storage.
The Bean Weevil is most active during: Year-round indoors; most rapid reproduction in warm months; thrives in Arizona's warm climate. Arizona's warm desert climate can extend activity periods compared to other states, so year-round vigilance is recommended in the Phoenix metro and surrounding areas.
Store dry beans and lentils in airtight containers. Inspect purchased beans. Freeze new bean purchases for 1 week to kill eggs and larvae. Rotate bean stocks regularly.
Discard all infested beans. Freeze suspect beans at 0°F for 1 week. Airtight storage for remaining beans. Clean and vacuum storage containers.
Left unchecked, Bean Weevil infestations can cause significant structural or food-storage damage over time. Destroys dry beans, lentils, and legumes from the inside. Multiple larvae can develop in a single bean. Rapid reproduction in Arizona's warm climate. Infestations often introduced through purchased beans. Early detection and professional treatment are the most cost-effective approach — contact Pest Control Bros for an inspection at the first sign of activity.
Dealing with Bean Weevil?
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