10 Types of Beetles Every Homeowner Should Know
Learn key characteristics of some common beetles found in the United States to understand whether they are friends or foes to your home and garden.
Do you have beetles invading your home or garden? If so, it’s time to learn more about these bugs that look like cockroaches (but thankfully aren’t). According to the Smithsonian, there are approximately 350,000 beetle species, with about 30,000 different types of beetles in the United States. Beetles can live in just about any climate, including lakes, rainforests, deserts, and even snow-covered regions.
Like other insects, they have three body parts (head, thorax, and abdomen) and two segmented antennae, which they use to smell. Beetles also have two pairs of wings, which are sometimes used for flying and protecting their bodies. Beetles go through complete metamorphosis, and some species can survive for up to 6 months or longer if there is enough available food. While beetles typically don’t bite (although they may if provoked), they can be aggressive or destructive to gardens and crops. Continue reading to learn how to identify some of the most common types of beetles found in the United States.
1. Ladybugs (Coccinellidae Family)
Ladybugs, also called ladybird beetles or lady beetles, have small rounded bodies (only 2 to 10 millimeters long) with two pairs of wings attached to the thorax. These wings may be either red, yellow, or orange and are often covered with black dots, though there are a few ladybug species with solid-black wings.
Seeing one of these small beetle species is regarded as a sign of good luck in many countries. In fact, seeing one in your garden is good luck for your plants. Despite their smaller size, one adult ladybug can eat as many as 75 aphids each day. Female ladybugs lay their eggs under leaves near a colony of aphids. The tiny larvae will consume hundreds of aphids before going through metamorphosis and reaching the adult stage in the life cycle.
Key Characteristics: These good bugs are small and round with black-spotted red, yellow, or orange wings.
Location: Across the world, particularly in temperate climates
2. Ground Beetles (Carabidae Family)
There are more than 2,000 species of ground beetles in the United States (with nearly 40,000 species in the world). Beetles categorized as ground beetles are another type that can be beneficial to humans. The adults hunt for their food in the soil—and sometimes on the leaves and plants themselves—ridding gardens of pests. A few species eat seeds of weeds and other plants.
While the adults in this beetle family have wings, it is rare to see a ground beetle flying, and some lack the ability to fly at all. In fact, most of a ground beetle’s time as an egg, larva, and pupa is spent belowground. Because the term “ground beetles” refers to such a large family of insects, the appearance of these bugs can vary, but many have a black shell with a metallic sheen. The covers for their wings have ridges, which they often use for defense. The size of this mostly brown-black beetle also varies widely, with some being as small as 1 millimeter and others as large as 66 millimeters.
Key Characteristics: Metallic black shell with ridged wing covers
Location: Across the United States and the world on the surface of the soil where there are small bugs to eat
3. Weevils (Curculionoidea Family)
Weevils are among the most common types of beetles found in the United States. There are more than 2,500 different weevil species in North America. They are very small—most less than 6 millimeters long—and may be brown, red, black, or gray, depending on the species.
Weevils are considered a nuisance pest. They have a long snout that they use to drill holes in foods such as cereal, sugar, rice, corn, and more. If a group of weevils gets into a home, they can destroy food reserves. Sealing any cracks and other potential points of entry and keeping your dry foods inside sealed containers can help protect your home. In addition to being pests inside the home, weevils can also cause serious damage to gardens and crops.
Key Characteristics: Small black, brown, or green oval body with a long snout
Location: Warm and moist places across the United States
4. Soldier Beetles (Cantharidae Family)
Soldier beetles measure about ½ inch long and have a black head and black wings with yellow, light orange, or tan wing covers. These yellow beetle bug species have black oval-shaped spots on each wing and a black spot just below the head. The soldier beetle’s body is shaped much like that of its firefly relatives; however, soldier beetles cannot light up like fireflies can.
Soldier beetles are among the beetle types that are good for the garden. The beetle larvae eat pests found in the garden. For this reason, many gardeners try to attract soldier beetles to their gardens.
Key Characteristics: Black head with yellow or tan wings, each with one black spot
Location: Across North America
5. Japanese Beetles (Popillia japonica)
Before 1916, Japanese beetles were found only in Japan. However, after the beetles were accidentally brought into New Jersey, they spread through several parts of the country. Now Japanese beetles are found along the eastern United States (except for Florida) and are slowly spreading farther west across the country; they are classified as an invasive species. The adult beetles can cause damage to the leaves of several types of plants. Serious damage can result in loss of fruits or vegetables growing on the plant or even death of the entire plant.
Japanese beetles can grow up to an inch long. They have a very distinct appearance with a metallic green thorax and head, and copper-colored wings cover their body.
Key Characteristics: Metallic green head and thorax with copper-colored wings
Location: Throughout the eastern United States (except Florida)
6. Blister Beetles (Meloidae Family)
If you’re looking for information on Arizona beetles, you might be seeing blister beetles. However, these insects are not confined to Arizona. In fact, there are more than 2,500 blister beetle species. Because of the sheer number of species, there is some variation in the appearance of blister beetles. They typically have long and narrow bodies, ranging from ¾ inch to 1¼ inch, and a very narrow neck. Some blister beetles are solid in color, while others have stripes or spots.
Another distinction between blister beetles and some other species relates to their wings. While most other beetles have hard front wings, the wings of a blister beetle are softer and more flexible. These beetles can leave blisters if they are crushed or rubbed against the skin. If consumed in large quantities, crushed beetles can be toxic for animals. Some species cause major crop damage as well.
Key Characteristics: Long and narrow bodies with a narrow neck and soft wings
Location: Throughout the United States
7. Eastern Eyed Click Beetle (Alaus oculatus)
The eastern eyed click beetle has two large white circles on its head that look like eyes, hence the name. However, these spots are false eyes, not real eyes. This species is a black-and-white beetle that is found in several areas of the United States, except for the South.
Like other click beetles, the eastern eyed species has a unique ability to get away from predators. When the beetles jump, they can spring off of their legs and propel themselves up to a foot in the air. As they jump, they make a clicking sound, which is the inspiration for their name.
Key Characteristics: Black-and-white body with large false eyes on head
Location: Throughout the United States (except for the southern part of the country)
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8. Golden Tortoise Beetle (Charidotella sexpunctata)
If you spot a metallic yellow-and-black beetle, it could be a golden tortoise beetle. Also called goldbugs, these beetles can be found along the eastern United States as far south as Florida and as far west as Texas and Idaho. Golden tortoise beetles are typically between 5 and 7 millimeters long.
The body of this beetle may be gold, yellow, or reddish brown and is covered with small spots. These insects can change their color as they progress through their life cycle and mate. They may also change color when disturbed or touched by humans. While golden tortoise beetles eat leaves, they do not typically occur in large enough numbers to do serious damage.
Key Characteristics: Golden, yellow, or reddish-brown body with small spots
Location: Eastern United States, south to Florida and west to Idaho and Texas
9. Striped Cucumber Beetle (Acalymma vittatum)
The striped cucumber beetle is a pest that is indigenous to North America. It’s especially prominent in the eastern part of the country, but can be found as far west as the Rocky Mountains. It feeds on cucurbits, a family of plants that includes cucumbers, squash, melons, pumpkins, and more. In addition to the damage it can cause from feeding on these plants and fruits, this striped beetle species also transmits a bacterial wilt pathogen. When this pathogen is spread, it can kill members of the cucurbit family.
Striped cucumber beetles have a body measuring between 8 and 13 millimeters. They are bright yellow with black stripes and a black head.
Key Characteristics: Bright yellow and black-striped body
Location: Mostly eastern North America, but they can be found as far west as the Rockies
10. Carpet Beetles (Dermestidae Family)
Carpet beetles are pests that can damage rugs, carpets, wool, linen, and other clothing items. A carpet beetle infestation can also be a serious problem for museums and similar locations if the insects chew through historic artifacts or animal specimens. The adult carpet beetles are not the problem, however. It is the beetles’ larvae that are responsible for chewing and damaging goods. When you consider that some of these beetles can remain in the larval stage for up to 3 years, it is easy to see how they can cause real damage.
Adult females also lay their eggs near materials that are more susceptible to damage, increasing the threat that the larvae can pose. Although there are more than 200 species of carpet beetles, many that you’ll find in the United States are small—just 3 to 5 millimeters long—with black oval shells.
Key Characteristics: Small body with a long, black oval shell
Location: Across the United States and around the world