One of the reasons brown beetles need to be taken seriously is their capacity to feed on different types of plants and legumes.
Some of these bugs even feed on softwoods and hardwoods, making it nearly impossible for the tree to survive in the case of a serious invasion.
Brown beetles often survive winters in the ground, sometimes feeding on the roots of various plants.
They emerge when the weather gets warm, feeding on their hosts and laying eggs.
Many brown beetles have been introduced from around the world, holding an invasive status. This is a status that implies rapid spread or a considerably negative impact on the environment.
Some brown beetles are even known borers. They bore into wood, often responsible for unseen tree damage.
Some of the most common brown beetles have a diverse diet and a diverse impact on the ecosystem.
The following species can be found in all climates with varying roles which may be negative or neutral when it comes to the impact on the ecosystem.
Table of Contents
1. Oriental Beetle
The Oriental Beetle (Exomala orientalis) shows a metallic brown color coupled with black sections.
Light brown colors with black spots color its thorax while its elytra show dark brown coloring with mottle black colors.
A small species growing to a maximum size of up to 0.4 inches, Oriental Beetles have an introduced status in North America.
They are often confused with other bugs with brown elytra but they can be correctly identified by the black spots on the thorax and their small black heads.
Brown nuance – dark brown, bright brown
Distribution – Asia (native), North America (introduced)
2. Japanese Beetle
The Japanese Beetle (Popillia japonica) and The Oriental Beetle are among the species often confused to their similar size and appearance of the elytra.
A lighter brown nuance is specific to the elytra of The Japanese Beetle.
Even more, its light brown elytra are coupled with a dark green thorax and not with a brown-black thorax as with The Oriental Beetle.
Similarities between these species are specific to size as both Asian-origin beetles grow to a size of up to 0.4 inches.
Brown nuance – copper-brown
Distribution – Asia, North America
3. Grapevine Beetle
Grapevine Beetles (Pelidnota punctata) eat the grapes and leaves in gardens and are often light brown.
This species is found around Eastern US states and it can be a species that grows more than 1 inch.
Most of its coloring is bright brown, with some room for color variations based on local populations.
Some are even brown and green while others show color differences between the standard black legs of the bug.
This species shows a light brown elytra with black margins and additional black spots right next to the thorax and along the elytra.
Brown nuance – bright brown
Distribution – Eastern North America
4. Reddish-brown Stag Beetle
The dark brown uniform color is specific to the Red-brown Stag Beetle (Lucanus capreolus). Its dark red undertones even make the bug appear black in low light.
This is a species with elongated mandibles that males use to assess their territorial nature.
Often found in woodlands, this is a species that grows in the ground as larvae which may take 1-2 years to emerge.
Some of the largest Reddish-brown Stage Beetles grow to a size of 1.3 inches.
Brown nuance – red-brown
Distribution – Eastern North America
5. Varied Carpet Beetle
Varied Carpet Beetles (Anthrenus verbasci) are some of the smallest brown beetles that can invade homes.
This species can feed on various natural fibers in the house and come in a reduced size.
Even the largest Varied Carpet Beetle grows to a maximum size of 0.14 inches.
Its elytra, thorax, and head show the same color combination. Brown, yellow, and black patches are seen together on the species. Brown or black colors are dominant across its elytra.
Brown nuance – bright brown
Distribution – North America, Europe, Asia
6. Eastern Hercules Beetle
The Eastern Hercules Beetle (Dynastes tityus) comes in different colors such as gray and tan. It may even come in pale green with brown spots.
A good amount of Eastern Hercules Beetles has a dark brown color. This color has wooden mahogany undertones.
Male Eastern Hercules Beetles are particularly known for their dual horns. A longer upper horn and a shorter lower horn help the beetle fight and flip over other males of the species.
Brown nuance – tan, mahogany
Distribution – United States, Mexico
7. Ten-lined June Beetle
Brown and dark brown nuances are seen on the Tan-lined June Beetle (Polyphylla decemlineata).
This species is named after its striped appearance as white, tan, or even gray vertical stripes can be seen across its elytra.
The head of the species and the thorax has a brown color with tan contrasting stripes.
Dark brown coloring is specific to the elytra which may also appear black at the base of the wings.
Short yellow hairs may also be seen across the brown areas of the beetle.
Brown nuance – brown, dark brown
Distribution – North America
8. Brown Prionid Beetle
Brown Prionid Beetles (Orthosoma brunneum) are mostly brown and light brown. They are some of the largest types of brown bugs in North America as they may grow to 2 inches.
Dark brown nuances are specific to the antennae, head, and base of the elytra.
The tips of the elytra are bright brown, similar to its legs.
Bugs of this species are a common sight in woodlands. They prefer fir and pine woodlands.
Beetles of this species often feed on pine sap.
Brown nuance – brown-red
Distribution – United States
9. Southern Masked Chafer
A species is known as a major pest in the Midwestern states, Southern Masked Chafers (Cyclocephala lurida) eat turf.
Their damages can be extensive, especially together with the larvae.
This is a species with dark brown and light brown stripes across the elytra when it matures.
A tan color or a brown color are the main morphs of the species. The Southern Masker Chafer tends to darken in dry habitats.
Brown nuance – light brown, dark brown
Distribution – North America
10. Brown Rove Beetle
Various shades of brown are specific to The Brown Rove Beetle (Platydracus maculosus).
This elongated-shaped bug has a darker brown. A dark brown Brown Rove Beetle morph also exists.
Bugs of this species often live on sandy terrains. The color of the sand and the ground also influences their appearance.
Golden marks are often seen on the brown body of the bugs in sandy areas.
When outside this habitat, Brown Rove Beetles can resemble earwigs due to their elongated abdomens.
Brown nuance – brown, dark brown
Distribution – North America
11. California Root Borer Beetle
A dark brown appearance is specific to The California Root Borer Beetles (Prionus californicus).
This is a species with long serrated antennae and dark red undertones across its elytra.
Found in woodlands, the species grows to a maximum of 2.2 inches and is known for its damaging role to various trees.
The adults only live for a short period as they don’t feed.
California Root Borer Beetle Larvae eat the roots of trees, on the other hand. Found in dry woodlands, these larvae chew on the roots of falling-leaf trees with the risk of killing them.
Brown nuance – dark brown
Distribution – Western North America, Baja California
12. Asiatic Garden Beetle
A mostly brown appearance is specific to The Asiatic Garden Beetle (Maladera formosae).
Its cephalothorax has a uniform brown color while its elytra shows alternating brown and light brown stripes.
Its underside and legs are also uniform brown.
Introduced to North America with flower imports, this species can feed on various cultivated flowers in gardens as well as with wildflowers such as asters.
Brown nuance – light brown
Distribution – Southern United States
13. Red-headed Ash Borer
The Red-headed Ash Borer (Neoclytus acuminatus) is an ant-mimicking brown bug. It has a brown color with red undertones and the shape of a wasp.
Its long legs and antennae are also brown while its brown body shows contrasting yellow bands.
This is a species named after it tends to bore into dead ash trees. While it likes ash, it can also bore into different other types of hardwood trees such as hickory.
There’s no threat to the trees themselves tied to this species as these bugs only bore into dead trees and lumber.
Brown nuance – dark brown
Distribution – Northern United States
14. Giant Stag Beetle
A dark brown color is specific to the Giant Stage Beetle (Lucanus elaphus). As one of the largest types of brown bugs in the world, this is a species that reaches a size of over 2 inches.
Darker brown nuances are specific to its thorax and legs.
Unlike other species, The Giant Stag Beetle is sexually dimorphic as males can be a few times smaller than females.
This species also has elongated brown horns which makes it look aggressive.
Brown nuance – brown, dark brown
Distribution – North America
15. Aloeus Ox Beetle
Aloeus Ox Beetles (Strategus aloeus) are named after their horns. These bugs have short horns in the case of females and long horns in the case of males.
Beetles of this family may be aggressive, fighting with their horns. They also use these horns to dig into the ground.
Beetles of this species are dominated by brown nuances.
Their heads and thoraxes tend to be darker brown, as opposed to the rest of the body.
Brown nuance – dark brown
Distribution – Southern US, Central America, South America
16. Ivory-marked Borer
Long antennae and a light brown body are characteristic of The Ivory-marked Borer (Eburia quadrigeminata), a species that grows to 1 inch.
Bugs of this species are always larger than 0.5 inches but their antennae can be even longer.
The name of these bugs is inspired by the ivory spots along its elytra.
4 spots with black divisive lines are specific to its bright spots on the back.
Ivory-marked Borers spend most of their lives laying eggs in dead wood.
Brown nuance – tan
Distribution – Southern US, Central America, South America
17. Oak Timberworm Weevil
These types of infesting weevils (Arrhenodes minutus) are named after their most typical host, The American Oak.
Weevils of this species have a red-brown color, dark brown nuances, and yellow nuances across the elytra.
Small differences are also noted between males and females. The male has longer mouthparts.
This species poses a high risk of infestation and a danger to various common trees in woodlands outside oaks. Elm and beech are also among the species which are prone to infestations.
Brown nuance – red-brown
Distribution – North America
18. Cedar Beetle
Cedar Beetles (Sandalus niger) are among the smallest types of brown beetles in North America.
This species grows to a size between 0.1 and 0.2 inches and it can be identified by its mostly dark brown appearance.
Only the outer margins of its elytra are light brown.
Small groove-like patterns are also visible across its body.
As its name implies, this is a boring beetle tied to cedar but also to other species such as elm.
Brown nuance – dark brown
Distribution – North America
19. Grape Colaspis
Grape Colaspis (Colaspis brunnea) is a bright brown bug with gray stripes across the elytra.
The color pattern of the species resembles the patterns of other invasive species such as those of The Colorado beetle.
Vertical stripes across the elytra are specific to this beetle while its cephalothorax is mostly bright brown.
A known pest of soybean, Grape Colaspis grows to a size of up to 0.02 inches.
Brown nuance – bright brown, tan
Distribution – North America
20. Clover Leaf Weevil
Mostly brown and bright brown, Clover Leaf Weevils (Brachypera zoilus) are only marginally larger than Grape Colaspises.
They reach a maximum size of 0.03 inches and are now also found in North America.
A brown-gray color is specific to these bugs which also show bright brown stripes along its margins.
Black spots further decorate the elytra of this species and the similarly-colored cephalothorax.
The legs of Clover Leaf Weevils are also gray-brown with black spots.
Brown nuance – dark brown, tan
Distribution – Europe, North America
21. Two-banded Japanese Weevil
Two-banded Japanese Weevils (Pseudocneorhinus bifasciatus) show a combination of bright and dark brown colors.
Weevils of this species have a rounded globular shape and can easily invade different flowers.
Hundreds of flowers are attacked by these bugs. From azaleas to dogwood, Two-banded Japanese Weevils can feed on various flowers in gardens.
Wildflowers are also impacted by these small weevils.
Early management techniques involve washing down the plants while large-scale control requires insecticide use.
Brown nuance – light brown, dark brown
Distribution – Japan, United States
22. Brown Leather Wing Beetle
A growing California presence is specific to The Brown Leather Wing Beetle (Pacificanthia consors).
This is a species that shows bright orange coloring with dark brown wings.
A dark brown nuance dominates its appearance as the elytra of the species are almost 2 thirds of its body.
The legs and antennae of the species also show a similar dark brown appearance and not an orange color specific to the cephalothorax.
Brown nuance – dark brown
Distribution – California
23. Twig Pruner
The Twig Pruner (Anelaphus villosus) larvae are known to infest various types of hardwood trees.
From elm to hickory, the larvae of the species are known to feed on the wood of various branches.
Detecting the larvae is difficult as it only eats the inner wood and not the bark of the branches.
Spotting brown adults around trees can be one of the early detection methods.
The adult of the species has a bright brown uniform color across the cephalothorax and the elytra.
It also has long brown antennae which are as long as its body.
Found across North America, this is a species that survives inside trees in a larval stage.
Brown nuance – light brown, gray-brown
Distribution – Southern Canada, United States
24. Pole Borer
A bright brown color is specific to the head, thorax, and elytra of The Pole Borer (Neandra brunnea).
This species has similarly colored legs and antennae.
Dark brown nuances are only specific to small parts of its body such as the margins of its elytra.
While it likes to live in wood, this borer brown bug doesn’t live in live wood. It prefers decaying wood and dead wood.
Its presence is confirmed on numerous trees and it is believed to live in almost any type of dead wood.
Brown nuance – bright brown, dark brown
Distribution – Eastern United States
25. Forked Fungus Beetle
This species of beetle (Bolitotherus cornutus) has a dark brown appearance and an elytra that shows irregularities.
It mimics tree bark to escape predators such as owls.
Forked Fungus Beetles aren’t specifically interested in trees themselves. They survive on the fungus that grows on trees.
At least a few types of fungi feed these small beetles which may reach a maximum size of 0.5 inches.
Spotting these types of bugs on trees in gardens isn’t easy as they only come out at night.
During the day, they bore themselves into the larger fungi growing on trees, mainly on the side with the most shade.
Brown nuance – dark brown
Distribution – Eastern North America
26. Little Bear
Little Bear beetles (Paracotalpa ursina) are known to eat different leaves. The grubs of the species are found feeding on the leaves of flowers and shrubs, in addition.
A brown elytron is mostly specific to The Little Bear. Its appearance is completed by a green thorax.
Brown and green coloring make this species easily confused with The Japanese Beetle.
Unlike The Japanese Beetle, Little Bear Beetles also grow white-gray hairs. These hairs cover their laterals and underside.
Furthermore, these types of beetles are also found around the deserts of the Southeastern United States.
Brown nuance – bright brown
Distribution – Southwestern North America
27. Carrot Beetle
The Brown Carrot Beetle (Ligyrus gibbosus) has a brown color with orange nuances.
A species also found in North America, The Carrot Beetle is known to feed on plants, particularly on flowers.
Its grubs feed on the roots of various flowers such as irises while adults feed on the leaves and stems of the flowers.
Controlling this species is possible by hand-picking at night. Preventing measures also include pruning and clearing dead plant parts.
Brown nuance – bright brown
Distribution – Canada, United States, Mexico
28. Painted Ladybird
The Painted Ladybird (Mulsantina picta) is one of the smallest types of brown bugs in North America.
Ladybirds of this species come in different clear colors or with patterned elytra.
Tan to light brown nuances are specific to The Painted Ladybirds that have no patterns.
Patterned morphs feature additional dark brown coloring on the elytra while the cephalothorax is white and black.
The larvae of this species are larger than the 0.01 inches adult as is all-brown.
Brown nuance – tan, bright brown
Distribution – North America
29. Tooth-necked Longhorn Beetle
Brown nuances dominate the appearance of the Tooth-necked Longhorn Beetle (Prionus pocularis).
This is a species with a dark brown head, thorax, legs, and antennae.
Its elytra is only dark brown at the base while the tip of its abdomen and the tips of the wings are bright brown.
This species also stands out with its very long serrated brown antennae.
Feeding on plants, this species is often compared to The American Cockroach due to its similar brown nuance and body shape.
Brown nuance – bright brown, dark brown
Distribution – North America
30. Brown Leaf Weevil
Seen in mostly brown elytra, The Brown Leaf Weevil (Phyllobius oblongus) is a species seen in the spring when it starts to feed on leaves.
It lives in woodlands, parks, and gardens, and it can be identified by its dark brown elytra and considerably smaller black thorax.
There’s a bronze nuance to its elytra that helps identify the species together with its hosts.
Brown Leaf Weevils prefer trees and feed on the young tree leaves from spring to summer.
These bugs overwinter in the ground in their larval stage.
Brown nuance – brown-brown
Distribution – Northeastern United States