Scientific name: Acanthoscelides obtectus
Distribution
Worldwide, but absent from some parts of East and South-east Asia.
Pest Type
Primary pest
Identification
Adult: 3.0–4.0 mm, dark in colour, elytra are variegate with yellowish and dark brown patches of hairs. The lower edge of the hind femur with three or four “teeth” or spurs.
Larvae: Scarabeiform, legs partly develop.
Life Cycle
At optimum conditions of 30 ℃ temperature and 80% relative humidity, the life cycle will be completed in 27 days. The eggs are laid loose on commodities. As soon as the larvae hatch, they bore into the commodity and complete the development inside a single seed. The adults leave a neat exit hole when they emerge, fly, do not feed on commodity, and are short-lived.
Commodities attacked
Beans from the genus Phaseolus— kidney beans, navy beans, pinto beans, and wax beans.
Economic importance
High, especially in bagged and stored beans in tropical and warm temperate regions which can cause heating and lead to mould growth.