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Alaus oculatus - The Big-Eyed Click Beetle

The Big-Eyed click beetle, formally known as Alaus oculatus, is one of the larger and more conspicuous members of the click beetle family (Elateridae).  Their nickname is representative of the large black and white-rimmed eye spots located on the pronotum, giving the appearance of a much more formidable opponent to its potential predators.  This species ranges across the eastern United States, from Texas and Florida up through parts of Canada.  The adult beetle is approximately 2-4 inches in length, and predominantly black with some white specks in addition to the eye spots.  A very similar looking beetle is the Small-Eyed click beetle, Alaus myops.  A. myops has smaller eye spots and darker mottling across the wings than A. oculatus, and occurs across the southeast US.

A. oculatus, the Big-Eyed click beetle (left); A. myops, the Small-Eyed click beetle (right)

PictureWireworm
Beetles (order: Coleoptera) are known for their hardened exoskeletons, which afford them physical protection and allow for a variety of habitats.  The Big-Eyed click beetle is typically found from late spring through summer as an adult, in or near deciduous forest habitats. They are often attracted to lights on people's’ houses at night, especially near wooded areas, and can be considered a nuisance (or really cool to look at!).  The grubs of click beetles are called wireworms, which are slow-growing and usually yellowish--brownish in color. One species of Ichneumonid wasp, Xorides catomus, is a noted parasite of these grubs.  Many click beetle larvae are crop pests, feeding on roots of grains and other plants including flowers.  Alaus oculatus grubs are often found in deciduous hardwood forests in decaying logs and are predacious to the grubs of other wood-boring beetles, namely Cerambycidae and Buprestidae.  Adults don’t eat much but have been shown to take nectar from flowers.  This beetle survives the winter as a wireworm and emerges in the spring as an adult to reproduce.

Click beetles have a special mechanism to right themselves, making that characteristic “click” sound.  Spines protruding backward on their pronotum are used in conjunction with their hardened bodies to snap part of the beetle’s back against the ground with force, shooting the click beetle nearly vertically in the air many times its length!  This self-righting mechanism shows promise in the field of robotics, allowing even robots without legs to jump and clear obstacles.  For more reading on the subject, including an awesome video demonstrating the beetle’s click mechanism, check out: https://www.nature.com/news/high-jumping-beetle-inspires-agile-robots-1.22981
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  • Alaus oculatus