Click beetles can be found all over the world and are known for the distinct clicking noise their bodies make. Most of the time these beetles are harmless, though the larvae can damage crops. As a result, some people consider them a nuisance.
There are thousands of species of click beetles. Some are relatively plain, while others have intricate patterns or glow at night. This wide variation coupled with their unique clicking mechanism makes click beetles one of the most interesting beetle species.
What Are Click Beetles?
Click beetles are a type of elongated beetle in the family Elateridae. These beetles are named for the way they can snap or “click” a spine-like structure between the segments of their thorax. They do this to startle predators or to help themselves flip over when stuck on their backs.
What do click beetles look like? Click beetles have long, somewhat flat bodies. Their bodies may be tapered or rounded at the end. They appear segmented into two pieces, with the head and first pair of legs on one part and the wings and other two sets of legs on the second part. Most species of click beetles are brown or black, and some have red or yellow markings. Size also varies between species, with some being as small as a quarter of an inch long, and others reaching 2.5 inches.
The larvae of click beetles are called wireworms. They are segmented, with hard, shiny bodies in shades of brown, tan, or white. Wireworms range in size from 0.5 to 2.5 inches long and have six tiny legs.
Click beetle lifecycle. The exact lifecycle varies by species. Generally, the female click beetle will burrow to lay her eggs, sometimes in rotting logs and sometimes in the soil around plants. A few weeks later, the eggs hatch. The larvae molt several times, and it can take anywhere from several months to four years for the larvae to reach the pupal stage. In late summer or fall they pupate in the soil, and a few weeks later emerge in their adult form.
What do click beetles eat? Not all click beetles eat in their adult form. Those that do usually eat plant material like foliage, nectar, and plant juices.
Most of their eating is done in the larval stage. Different species have different diets, with some eating decaying material in logs or soil, some eating the grubs of other beetles, and some eating plant material like roots, seeds, and sprouts. In some cases, the plant-eating larvae can damage crops.
Types of Click Beetles
There are thousands of species of click beetle around the world, and nearly a thousand in the U.S. alone.
Eyed click beetle. The eyed click beetle (Alaus oculatus) is one of the most striking species of click beetle thanks to the large round ovals on the back of their heads that resemble eyes. They usually grow to about an inch and a half in length and have mottled spots on their bodies. This species is found throughout the eastern U.S. as far west as Texas and South Dakota.
Glowing click beetles. Some types of click beetles, like those in the genus Deilater, are bioluminescent. These beetles have spots on their bodies that glow, similar to fireflies. Unlike fireflies, these beetles don’t flash their flow, but they may be able to adjust the intensity of the light. Their larvae are bioluminescent as well.
Where Do Click Beetles Live?
Click beetles can be found throughout the world in a variety of environments except for those that are very cold, very wet, and in deserts. They can often be found in gardens and yards, really anywhere with grass and leafy plants. Larvae live in the soil, but you may spot an adult click beetle on the ground or on plants.
Adult click beetles are mostly nocturnal, so you’re more likely to see them at night. They’re attracted to light, so you may see them buzzing around your porch light in the evenings or resting on a wall near a light.
Signs You Have Click Beetles
Click beetles don’t usually invade homes, though they have been known to come indoors in years with especially high numbers of click beetles. If a click beetle finds its way into your home, you may see it or hear its “click.”
Because the larvae live underground, you may not be aware that your crops are infested until they start to show signs of damage. They’ll leave behind chewed-up seeds and plant parts.
Why Do You Get Click Beetles?
If you find a click beetle in your home, it’s likely it was attracted to indoor light and found a crack or open window to come through.
Wireworms are more likely to infest specific types of soil. They prefer soil that isn’t tilled often and are more likely to be found in soil that has been growing alfalfa, grain, or cover crops.
Health Risks of Click Beetles
Generally, click beetles do not harm people and pose no health risks. On very rare occasions they may bite if you’re holding one and handling it roughly. But they don’t drink blood, so they don’t set out to bite.
How to Get Rid of Click Beetles
If you’re discovering click beetles in your home, you don’t need to haul out the pesticides. The best way to handle click beetles in your home is to figure out where they’re coming in. Because they’re attracted to light, they’ll often try to come in under glass doors, which let light through, or under doors near porch lights. Other areas to check are screens and windows. Make sure your screens are uncompromised and doors and windows are properly sealed.
If you’re growing crops, there are things you can do to reduce the likelihood of a wireworm infestation, such as clean cultivation and clean fallowing. Planting crops like cotton during warm weather and in shallow soil may help them outgrow wireworm damage.
If you discover wireworms damaging your crops, you may want to reach out to a local entomologist or agricultural expert. Management of wireworms will depend on the specific crop they are infesting.