Click beetles are elongate beetles with a hard exoskeleton, with the head deeply retracted into the thorax. When disturbed they lie on their back feigning death and then suddenly propel themselves into the air with a audible click. Hence their name. Their larvae are called wireworms and feed on the roots of many plants.
Life cycle and appearance of Click beetles
Adult Agriotis sp. are 6-10 mm long and yellowish brown to black. The eggs are laid in May or June in groups in the soil. They hatch about one month later and the larvae start to feed on roots. The larvae (‘wireworms’) are long, thin, cylindrical and though skinned. They are up to 25 mm long and usually shiny yellowish brown or light brown with a darker head.
Larval development takes 4 to 5 years. When fully grown the larvae pupate in the soil in summer. The adults appear about 4 weeks after pupation, but usually remain in the soil until the following spring.
The click beetles feed on the roots and bore into the base of plants. This can cause the plants to wilt and die. Damage is more severe in young plants.