Lined Click Beetle

• Click beetles have a spring mechanism in the thorax: if they land on their back, they release it with an audible click and are flung into the air until they land the right way up.
• The larva can spend four or five years in the soil before turning into an adult, which means an infested plot takes years to clear.
• Its elongated, hard, yellowish and very tough body is what gives it the name wireworm.
• The adult is a click beetle: if it lands on its back, it arches its body and abruptly releases a spring mechanism in its thorax that flings it into the air with an audible click, up to several times its own height, so as to land the right way up.
• That jump generates accelerations of several hundred g, among the highest known in any animal, without using the legs.
• The larva, the wireworm, is a major agricultural pest: hard, cylindrical and amber-coloured, it lives in the soil for up to five years and bores into potatoes, beets, seeds and roots.
• That larval longevity complicates its control, because several generations coexist in the same field at once.
• It is especially problematic in crops that follow grassland, because the larva was already in the soil before sowing.

Skeleton type

Invertebrate - chitin exoskeleton (insect)

Habitat and environment

Soils of grassland, cereals and root crops

Size at birth

The first-instar larva is white and measures 1-2 mm; the mature larva reaches 15 to 25 mm

Gestation / incubation

The eggs hatch after about four weeks; the larva spends several years in the soil with 8 to 14 moults and the pupa lasts another four weeks

Litter / clutch size

100 to 300 eggs per female, laid in damp soil covered with vegetation, in clusters rather than spread out evenly

Sources consulted: Wikipedia (es): Agriotes lineatus · Hebrew University of Jerusalem · AGES (Austria), ficha Wireworm · AGES (Austria) · Bayer Crop Science, ficha Wireworm · fichas de manejo de Agriotes spp · Hebrew University of Jerusalem, ficha Agriotes lineatus

Best time: The adults appear in early spring after overwintering in the soil, with the main laying between May and June; they emerge from the pupa in July or August and hibernate until the following spring