Hobby OrchardPecans, Fruit Trees, and Other Stuff

Our cat brought this little guy up to the back porch for us to admire.

Nearly two inches long and found across the eastern U.S. as far west as Texas, this gray and black and white insect is one of the largest members of the Click Beetle Family (Elateridae); the huge eyespots on its pronotum make it one of the most easily identified. These are “false eyes,” of course–likely an adaptation to scare off potential predators. The true eyes of the Eyed Click Beetle are much smaller and located at the bases of its heavily sawtoothed antennae (below left).

Despite their differences in appearance, all Click Beetles have a startling behavior that demonstrates how they got their primary name–as well as the alternate names of “snapping beetle,” “skipjack,” and “spring beetle.” When placed on its back–or when grabbed by an insectivore–a Click Beetle bends its head and prothorax backward and then straightens out suddenly with a snapping motion, which results in an audible click and launches the beetle several inches into the air. This stunt is facilitated by a spine on the underside of the prosternum that fits into a groove in the mesosternum (below).

Occasionally, a Click Beetle will take flight during its midair maneuver, but more often it simply falls back to earth. If it lands on its back, the beetle may “click” again, or it may tightly tuck its legs and antennae and “play possum” until the predator loses interest. Eventually, it will wander off, perhaps looking for food (flower nectar or leaf sap) or a mate.

Click Beetles–like bees, ants, butterflies, and some other insect orders–undergo a four-stage (complete) metamorphosis that includes the egg, larva (AKA “grub”), pupa, and adult. Although adults are harmless, Click Beetle larvae cause significant agricultural and horticultural damage. Click Beetle grubs–also known as “wireworms” because of their elongated shape and hard exoskeletons (above right)–live in soil or dead wood for two to ten years, depending on the species. During that time, they chow down on roots and stems– including those attached to corn, potatoes, tobacco, turf grasses, garden ornamentals, and a variety of legumes.