What Do Beetles Look Like?

Function

• As you would expect from a family of insects that boasts thousands of species beetles can vary greatly in appearance. But like all insects they have a head, a thorax and an abdomen. The midsection, the thorax, is the part that all six legs grow from and from where both pairs of wings also grow. Beetles possess a hard plate on their backs called a pronotum. The exoskeleton of beetles is also hard, and the majority of species have a hard pair of forewings known as elytra. These are not used for flying but rather to protect the second pair of wings called the alae. In order to fly the elytra must be raised to expose the alae.

Identification

• Over the eons, some beetles have lost their ability to fly, as the elytra have fused together and now are used like a shield over the abdomen. These are the ground beetles that most people think of when they hear the word beetle. Beetles have mouths that are quite similar in nature to those of the grasshopper. Many species have mandibles, which resemble pincers on the front of their mouths. They are hard and are used by beetles to grasp and crush, useful for eating and for fighting enemies. They have appendages near the mouth that move food into it to be consumed.

Types

• Beetles have different types of eyes that are adaptations over the years in response to the needs of the beetle in coping with its environment. For instance, the whirligig beetle, which lives in the water, has eyes that are split to allow it to see above and below the water. The antennae of the beetle are used mostly for smell and differ tremendously from species to species, even from male to female within the same species.

Considerations

• Most beetles use their legs for walking, but some water beetles have modified legs for navigating through the water. The legs of most beetles have more than one segment. There are beetles that can walk, dig, and jump with legs having evolved for these specific purposes.

Expert Insight

• Beetles undergo a change from an egg to a larva to an adult beetle. The larvae are furious feeders, eating as soon as they emerge from the egg. Some consume plants while other beetle larvae are predators. The beetle remains in the larval stage sometimes for as long as several years. The beetle larva has a darker head than most insects at this stage of development and it is harder, too. They also have mouthparts capable of chewing.