A to Z of Pests

Yellow Mealworm Beetle

Tenebrio molitor

Appearance

• Adults – 20mm long. They are shiny, dark–brown or black.
• Larvae are honey–yellow, they have a smooth, highly polished, shiny, elongate, hard, worm-like body, and can grow to 30 mm long.

Lifecycle

• Each female lays about 275–600 eggs singly or in clusters during the spring. They are white, bean-shaped and about 1mm long and hatch into larvae in 4 to 14 days.
• The pupal stage lasts 7 to 24 days during the spring. Pupae are first white, turning yellow, and are not enclosed in a cocoon.
• Adults emerge in the spring or early summer, living for two to three months.

Habits

• They are highly resistant to cold temperatures.
• It is an important post–harvest pest and occurs spread all over the world.
• Adult beetles are attracted to night-lights, are strong fliers, and are found in dark places.