(Acanthoscelides obtectus)

The Bean Weevil is a small beetle that belongs to the family Chrysomelidae. It is a significant pest of stored legumes, particularly dry beans and pulses, and can cause damage to stored products in agricultural and food storage facilities.

Larval Feeding: The larvae of Bean Weevils are internal feeders, causing damage by tunneling into the seeds and consuming the cotyledons.
Flight Capability: Adult beetles are capable of flight, allowing them to disperse and infest new areas.
Control:
Control measures for Bean Weevils involve maintaining proper storage conditions, including temperature and humidity control. Regular inspection and monitoring of stored legumes are crucial for early detection. Integrated pest management strategies may include the use of insect-proof storage containers, sanitation practices, and, if necessary, the application of insecticides or fumigation.

Given their ability to infest stored legumes and cause economic losses, effective management of Bean Weevil infestations requires a proactive approach to storage hygiene and pest control.

Overview

Biology

Appearance: Adult Bean Weevils are small beetles, typically measuring about 2 to 3 millimeters in length. They have an oval-shaped body with a mottled brown coloration. The elytra (wing covers) may have variable patterns, including spots or stripes.

Food

Life Cycle: The life cycle of the Bean Weevil includes egg, larva, pupa, and adult stages. Female beetles lay eggs on or near stored legumes, and the emerging larvae bore into the seeds and feed on the cotyledons. The pupal stage occurs within the seed, and adult beetles emerge to continue the life cycle.
Reproduction: Bean Weevils reproduce rapidly, and the development from egg to adult can be completed in a few weeks, depending on environmental conditions such as temperature and humidity.

Bean Weevils are commonly found in stored legumes, especially in facilities where dry beans and pulses are stored in bulk. They infest a variety of leguminous crops, including common beans, chickpeas, lentils, and peas. The larvae bore into the seeds, causing damage and reducing the quality of stored products.

Description

The primary food source for Bean Weevils is stored legumes. They infest dry beans and pulses, causing damage by tunneling into the seeds and feeding on the cotyledons. The larvae can significantly reduce the nutritional value and market quality of stored legumes.