Cowpea weevil, Callosobruchus maculatus, adults have long antennae and long legs with an enlarged femur on the hind leg that bears a single, large tooth. The wing covers of the weevil have a large, rounded spot at mid-length. They do not completely cover the abdomen, leaving part of it exposed. Like rice weevils, cowpea weevil adults sometimes play dead when disturbed.
Cowpea weevils lay eggs on leguminous seeds such as chickpea, pigeon pea, garden peas, mung beans, cowpeas, black-eyed peas, soybeans, peas, lima beans, and lentils. The eggs hatch and the first instar larva then burrows into the seed to begin consuming it from the inside. All larval stages are spent inside the seed, where they remain concealed and protected as they feed. The last instar larva pupates inside the seed. After emergence from the pupa, the adult beetle chews its way out of the seed, leaving a characteristic round hole in the seed’s shell (Figure C). Although adults are short-lived and do not feed, they are very active, known to run rapidly, and are strong fliers.