A to Z of Pests

Maize Weevil Beetle

Sitophilus zeamais

Appearance

• Adult up to 4mm.
• They are dull red-brown to nearly black and are usually marked on the back with four light reddish or yellowish spots.

Lifecycle

• The female chews a small hole into a grain kernel, into which one egg is laid. A female can lay 300 to 400 eggs over a period of months.
• An egg hatches in a few days into a larva, which feeds on the interior of the grain kernel. Pupation follows, with the adult beetle emerging later.
• The entire life cycle takes from four to seven weeks.

Habits

• The maize weevil has fully developed wings beneath its wing covers and can fly readily.
• This pest destroys stored crops such as corn, wheat, and rice.