The six-spotted tiger beetle is a beautiful, shiny insect. They are often seen on woodland trails, just a few steps ahead of you. As you move toward them, they will fly and land ahead, always staying just out of reach.
Their scientific name is Cicindela sexguttata. These are all Latin words. Cicindela means glow worm, sex means six and guttatus means spotted or speckled. Their metallic color flashes like a glow worm in the sunlight. They have six white spots on the bottom edges of their elytra. Elytra are the hardened forewings of beetles. Although they are named in part after the six spots, the number of spots can vary from zero to eight. Their color may also vary from brilliant emerald green, which is most common, to a deep metallic blue.
Their large bulging eyes give them a wide view of what is around them. This makes them hard to catch. They may even turn around to boldly face a would-be predator. If caught, they can emit a foul-smelling chemical, causing their capturer to drop them. They will be eaten by fast-moving predators like birds, dragonflies, robber flies and even other tiger beetles.
The adults often camouflage themselves on bright green leaves and attack once food passes by. They will eat many types of insects and spiders. They are about a half-inch long, but they can successfully attack and eat prey larger than them. Their mouth parts are white, and the mandibles, or jaws, grasp and crush their prey with great force. Their strong jaws and excellent stalking abilities are why these beetles are named after tigers.
The female will use her ovipositor to make a small hole to lay eggs in. An ovipositor is the egg-laying tube present in many female insects. Female tiger beetles will lay one egg at a time, usually covering each hole with loose dirt. When the larvae hatch, they will dig vertical burrows into the soil that can be up to 2 feet deep. They will patiently wait at the surface of the burrow for unsuspecting prey to walk by. Then they quickly grab the insect or spider and drag into their burrow to feast. The larval body has a hump with hooks about halfway down the length of its abdomen. This allows them to anchor in place, so it is it difficult to be pulled out of the safety of their burrow.
Like butterflies, tiger beetles have a four-stage life cycle: egg, larva, pupa and adult. When ready to transform, the larvae will fill in the top of their burrow with soil. Their pupal stage will last about three weeks. They do not eat during this time. When their transformation is complete, they emerge as adults living on the land instead of underground. Their long legs let them move fast on the ground, and they are also great flyers.
The adult beetles will return to their larval burrows to wait out the winter. They emerge in the spring ready to eat and mate. They can live up to three years.
These beetles are most active in the daytime from late spring through early summer. Their bright and dazzling color make them an exciting addition to any walk in the woods!
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