Beetle (Click) Family: Elateridae Elateridae
Common names: Click Beetles
Insects in the family Elateridae are commonly called click beetles. There are about 9300 known species worldwide and over 130 endemic species and 3 introduced species in New Zealand
Adult click beetles are found on the ground, on plants, in decaying wood or under bark. These cosmopolitan beetles are long and thin (12-30 mm long) with grooves running down their wing covers. The front of their heads and the back end of their wing covers are rounded. The first segment is flexible and the head and first pair of legs can move separately from the rest of the body generating the unusual click mechanism that they possess. A spine on the prosternum (the sternum of the prothorax) can be snapped into a corresponding notch on the mesosternum (the ventral piece of the middle segment of the thorax); producing a violent "click" that can bounce the beetle into the air. Clicking is mainly used to avoid predation, although it is also useful when the beetle is on its back and needs to right itself.
Adult click beetles feed on nectar, pollen, flowers, and sometimes soft-bodied insects like aphids.
The larvae: The click beetle larvae (wireworms) are slender, elongate, cylindrical or somewhat flattened, with tough segmented bodies and have mouth parts that point straight forward. They live in the soil but some are found under bark or in decaying wood.
The larvae are predators on small soil animals, but some eat roots and seeds. They usually spend three or four years in the soil, feeding on decaying vegetation and the roots of plants, and often causing damage to agricultural crops such as potato, strawberry, corn, and wheat. The subterranean habits of wireworms, their ability to quickly locate food by following carbon dioxide gradients produced by plant material in the soil, and their remarkable ability to recover from illness induced by insecticide exposure (sometimes after many months) make it hard to exterminate them once they have begun to attack a crop. Wireworms can pass easily through the soil on account of their shape and their propensity for following pre-existing burrows, and can travel from plant to plant, thus injuring the roots of multiple plants within a short time.
The click beetles timeline
Photos of some beetles of the family Elateridae.