Beetles are a remarkably varied group of insects found in nearly every corner of the globe. With over 300,000 species worldwide—and 12,000 in the United States alone—these creatures have adapted to live on land and in freshwater. Most beetles live for about one year and are characterized by having two sets of wings. Because they possess limited vision, they rely on sound, vibrations, or chemical signals called pheromones to communicate with one another.

While some beetles are considered pests, many are beneficial or even culturally significant. For instance, ladybugs are often viewed as symbols of good luck, and bioluminescent beetles like fireflies and lightning bugs use light to signal to each other in the dark. In the environment, beetles play complex roles: some species damage property and crops, while others help the planet by decomposing dead trees, removing waste, or pollinating flowers.

The Varied Carpet Beetle

The varied carpet beetle is named for the distinct, colorful patterns on its back. These insects have a long developmental cycle, taking up to three years to grow from an egg to an adult, yet the adults only survive for about 13 to 44 days. They are small, round insects—roughly 1/16 of an inch—with black bodies marked by yellow, white, and brown patches.

Scientifically classified as Anthrenus verbasci, these beetles are commonly found in attics or tucked into tapestries and carpets. Their diet consists of organic animal fibers, including wool, silk, fur, feathers, and even bone. To prevent these pests from ruining upholstery or clothing, it is best to store unused garments in airtight plastic containers and ensure clothes are dry-cleaned and kept off the floor.

The Destructive Powderpost Beetle

Powderpost beetles are small, reddish-brown to black insects known for their flat, narrow bodies. Measuring between 1/8 and 1/4 of an inch, these beetles are strong fliers and are notably attracted to light sources. They belong to the family Lyctidae and the species Lyctus brunneus.

These beetles are highly specialized, laying their eggs in the tiny cracks of hardwood. Their larvae feed on the wood, creating tunnels and holes that can severely damage hardwood floors, antique furniture, and structural timbers. In extreme cases, they have been known to cause enough structural damage to destroy entire houses. Homeowners can prevent infestations by inspecting wood sources before bringing them indoors and by ensuring that raw or exposed wood is properly painted or sealed.

The Resilient Merchant Grain Beetle

The merchant grain beetle is characterized by an extremely flat, brown body that allows it to squeeze into tight spaces within food packaging. An adult, which measures about 1/10 to 1/8 of an inch, can live for up to three years and matures from a larva in just a few weeks. Despite the name, these beetles do not actually eat whole grains; they were historically named "merchant" beetles because they were frequently found hiding in the organic cargo of merchant ships.

In a household setting, these beetles are usually found in pantries or kitchens. They prefer foods with high fat content, such as cookies, chocolate, cake mixes, and macaroni. Their presence can contaminate stored food through waste and egg-laying. To keep these pests away, it is important to clean up food spills immediately and promptly discard any packages that show signs of infestation.