You should know by now that many types of beetles exist in Washington State.
Oh, wait! Let’s talk a little about beetles themselves. You’ve never heard of beetles before, but what do you know about these creatures?
You may be surprised that there are over 350,000 different types of beetles today! One in every four insects in the world is a beetle!
These fascinating insects have been around on Earth for millions of years and have adapted to almost any environment they could find.
With so many different types of beetles available, it’s no surprise that some unique ones are found in Washington state alone!
Here are unique types of beetles in Washington state!
1. Darkling Beetle
Tenebrionidae, commonly known as darkling beetles, is one of roughly 15 families of a suborder known as dermestid.
About 3,000 species make up the family. They are small insects with oval bodies and long, slender legs.
This suborder gets its name from its habit of feeding on dead animals and insects found on living animals.
Darkling beetles are found throughout North America, usually among animal dung or carrion.
As scavengers, they do not attack living animals or plants.
But if threatened by an attack, they will defend themselves by releasing chemicals that smell unpleasant to predators.
2. Marsh Beetle
The Marsh beetle is the second on our roll of the numerous types of beetles in Washington state.
Also known as snake feeders, marsh beetles are a type of dung beetle.
As its name suggests, it is fond of snakes, but will also eat small mammals.
Certainly, the species is notable for having three distinct color morphs—reddish-orange, black, tan, or gray.
3. Ornate Checkered Beetle
This beetle is one of the interesting but dangerous types of beetles in Washington State.
This is a big collector’s favorite because it is so colorful and shiny.
However, it also has a few other qualities that make it rare. To begin with, its coloring warns predators that it tastes terrible (like other checkered beetles).
But then, its outer shell also has venomous spines that can cause pain for any predator stupid enough to swallow it.
So, if you’re ever tempted to pick up an ornate checkered beetle, don’t! This one’s best left alone!
4. Pine Sawyer Beetle
A type of longhorn beetle found commonly throughout western North America.
Despite being called a pine sawyer beetle, it is actually quite harmless and only eats fungi.
These are types of beetles in Washington state that you don’t have to worry about.
It can grow up to 5.9 cm long with long, slender legs, giving it a spider-like appearance.
This makes them particularly easy to spot—one less insect you’ll have to worry about at night!
5. Pink Spotted Lady Beetle
Pink Spotted Lady Beetles, also known as ladybugs and ladybird beetles, are very small, reddish-orange lady beetles.
They have black spots on their wing covers (elytra), which can be seen when they are removed from their shell.
These insects are important biological control agents that help farmers by controlling aphids and other plant-feeding insect pests.
Their bright colors warn predators to stay away because they taste bad to birds, lizards, and spiders.
Well, they are beneficial insects on our list of the types of beetles in Washington state!
6. Predaceous Diving Beetle
The predaceous diving beetle is a small, predatory aquatic insect that feeds on various larvae and fish.
They are relatively short-lived beetles, with males living for 3 to 5 weeks and females for 6 to 8 months.
Depending on water depth, females lay their eggs on submerged plants, rocks, or debris and can release up to 100 eggs at a time.
The larvae go through several developmental stages (i.e., instars).
They take 12 to 90 days to develop into an adult beetle, depending on water temperature conditions.
Adults are usually less than 1 inch long when fully grown, but some grow as large as 11⁄4 inches long.
Both male and female beetles have feathery antennae that aid them in swimming.
7. Ponderous Borer Beetle
This is also on our list of different types of beetles in Washington state.
Native to Africa, Ponderous Borer beetles were accidentally introduced to Washington over 100 years ago.
They are now found all over eastern Washington and can be identified by their green wing coverings (or elytra).
The beetle’s body is mostly orange and black with two large antennae.
8. Metallic Wood-boring Beetle
Considering the types of beetles in Washington state, many types of insects come to mind when you hear wood-boring beetles.
Typically, these beetles have long, slim bodies, hard exoskeletons, and chewing mouthparts used to chew through wood.
Metallic wood-boring beetles (Acmaeodera spp.) look a lot like other beetles, but they can be easily identified by their striking colors, ranging from green to red to brown.
Furthermore, the Metallic Wood-boring Beetle (Acmaeodera spp.) is so named because it has such pretty colors and bores holes into trees for shelter.
9. May Beetle
As you might be able to guess from their name, May beetles are a common sight during the spring and summer months.
The adult beetle is large with a black shell, measuring around 1 inch across.
A popular nickname for these critters is Daddy Longlegs, but they aren’t spiders.
Instead, they belong to another entirely different order of insects: Coleoptera.
Also called false wireworms due to their larval stage (considered pests), these beetles lay eggs in decaying matter, where their larvae feed on animal or plant tissue until they mature.
10. Banded Alder Borer Beetle
I noticed something interesting when I was walking around Seattle’s Green Lake on a recent family vacation.
Underneath a tree with some bark torn off of it was an insect that looked like a small creature from outer space.
Upon further investigation, I discovered it was a beetle type—the Banded.
Alder Borer Beetle (Rosalia funebris), also known as the space bug.
While it’s not unusual to find insects around Seattle, finding one that looks like an extraterrestrial is rare!
11. Mottled Tortoise Beetle
The Mottled Tortoise Beetle is a winged beetle that ranges from 5 to 10 mm long and has a brown, mottled shell and orange/red legs.
The species can be found throughout North America, including parts of Washington.
These beetles are attracted to citrus but also lay their eggs on hollyhock plants or lettuce.
Moving on, larvae eat leaves, flowers, and buds on multiple plants before pupating underground.
Because they feed on many different types of plants, adult Mottled Tortoise Beetles aren’t considered a threat to agriculture.
However, due to their voracious appetites as larvae, you probably won’t want them in your garden!
These types of beetles in Washington state are also interesting because males have larger antennae than females.
12. Mealybug Destroyer
The black mealybug destroyer is a beetle that feeds on every life stage of mealybugs, a sap-sucking pest.
The tiny brown beetles are about 1/4 inch long. A beetle will lay between 30 and 50 eggs during its lifetime, which lasts up to one year.
Not only does it eat other insects, but it’s also an egg cannibal. If there aren’t enough mealybugs for everyone, some beetles will eat their own eggs!
Undoubtedly, they are very voracious eaters on the roll of the various types of beetles in Washington.
Note: Black mealybug destroyers don’t usually overwinter in colder climates; they need temperatures above 50 degrees F.
13. Narrow-collared Snail-eating Beetle
Scaphinotus angusticollis, native to western North America, is a large longhorn beetle that primarily eats snails.
So, how does it eat them? Well, it doesn’t bite off their heads as you might expect.
Instead, it kills them by emitting a chemical that neutralizes their protective slime layer!
Currently, scientists are trying to figure out whether other species of Scaphinotus beetles use similar methods to kill snails.
If they do, then farmers could potentially control snail populations in their crops with fewer chemicals.
Snail-eating beetles like S. angusticollis may be able to play an important role in sustainable agriculture.
Thus, this may make them one of the most useful types of beetles in Washington state and the world at large!
14. Net-winged Beetle
The net-winged beetles get their name from their perfectly square elytra (wing covers) that look like nets.
The squared shape helps camouflage these tiny beetles on flowers and plants, which is advantageous because they eat pollen and nectar.
Their average size is about 2–4 mm, but females are slightly larger than males.
Net-winged beetles aren’t just types in Washington state; they are widespread across Canada, the United States, and even into Mexico.
They can be distinguished by dark brown coloration with black antennae and a net-like pattern on their hindwings.
If you see one of these guys while hiking, take note—it’s a rare sighting!
15. American Oil Beetle
This beetle, one of the types of beetles in Washington state, gets its name from its diet, which consists mainly of oil.
It is considered beneficial because it attracts ladybugs and other beneficial insects to gardens and yards where they eat destructive pests.
The American Oil Beetle is native to North America but is also found in Europe and Asia.
This beetle has a black body that’s covered with bright orange spots.
16. Devil’s Coach Horse
Also known as Devil’s Coach-Horse, Olens, or Olenus, Ocypus olens (formerly Rhinoceros Beetle) is a large species (up to 5.25 inches long).
It has black and yellow markings on its back and is frequently mistaken for a rhinoceros beetle because of its size and coloring.
Further, these beetles are predatory insects that hunt down other insects by trapping them in specialized grooves on their bodies to digest them.
They have been seen eating smaller beetles, caterpillars, and ants.
Devil’s Coach Horse Beetles are abundant near streams or rivers with sandy soil throughout western North America.
17. Drugstore Beetle
Of the types of beetles in Washington state, the drugstore beetle is a common pest found in bookstores, libraries, and other areas where grains are stored.
They’re known for chewing holes in cardboard containers to get at food items inside.
The adult beetles are reddish-brown and between one-quarter and one-half inches long.
Additionally, females lay clusters of eggs, which hatch into larvae (little worms).
These larvae develop inside grain products like cereal or bread before emerging as an adult beetle after several weeks.
Drugstore beetles feed on dry pet food because it’s often kept in cardboard boxes.
This makes these bugs a more common problem with dogs than cats.
18. Dung Beetle
The dung beetle is a scarab beetle best known for its amazing ability to roll and bury manure.
The dung beetle comes in two main varieties: Cave-dwelling beetles live underground and feed off manure.
And then there are tunnelers, who stay close to home but don’t eat human waste.
Both types dig long underground tunnels where they store their cargo; they then return later to feed on it.
Dung beetles are a type of beetle in Washington that are also popular pets for children due to their easy care requirements.
19. False Bombardier Beetle
Checking through the list of different types of beetles in Washington state, I found this to be a beautiful beetle! It’s about an inch long and shiny metallic red, except for an orange-red section on its underside.
Interestingly, its unique name comes from its defense mechanism: If a potential predator grabs it, it doesn’t run away as most insects do.
Instead, it shoots a hot chemical spray that would make your eyes water.
This is a group of beetles with 22 species, but they all share similar characteristics.
They live in warm climates and can only be found as far north as Arizona.
If you want to look at these guys, you must travel south during their migration or summer mating season.
Only two varieties can be found in Northern California—the rest are restricted to southern states like Texas and New Mexico.
20. Bee-like Flower Scarab Beetle
These beetles can be found throughout most of North America and are about 1⁄4-inch long.
Flower scarabs are dung beetles that feed on animal waste and carrion (dead animals).
Also, they’re used by humans to control pest flies. Did I mention that they are a very adorable type of beetle in Washington state?
Often, these insects enter homes searching for food, especially during droughts or colder winter months.
Don’t be afraid if you find one inside your home; it won’t harm you.
Though they may seem cute at first glance, flower scarab beetles can emit an unpleasant odor to protect themselves against predators like spiders and wasps.
21. Fire-colored Beetle
This flashy beetle is native to Asia but can be found here in Western Washington.
The bright-red beetles are usually found on conifers and particularly like to stay near rotting logs and dying trees.
For these reasons, it is considered a pest; however, some Fire-colored Beetles are kept as pets due to their striking coloration.
If you’re not into keeping beetles as pets, don’t worry—they can do very little damage and tend to move away from human habitation if left alone.
These insects have been spotted within a mile or two of Seattle proper.
However, they are most common at higher elevations within the Mount Baker-Snoqualmie National Forest in Whatcom County.
22. Big-headed Ground Beetle
The Big-headed Ground Beetle is a species of Scarabaeidae native to North America. They can be found under rocks, logs, or leaf litter.
Because they live deep beneath debris and never come out, they are hard to find without disturbing their habitat.
One way to ensure you don’t inadvertently hurt one is not to pick up any large rocks or sticks until you are certain nothing lives underneath them!
23. Hairy Rove Beetle
The hairy rove beetle resembles a miniature rhinoceros. With two long horns curving back from its face, it’s often mistaken for some kind of dinosaur or mythical beast.
However, that’s not surprising, as it typically only grows to be about 1/3-inch long.
The hairy rove beetle is one of over 5,000 species of beetles found in Washington state alone and likely makes its home within various habitats.
Since it spends most of its time hidden away under rocks and in other crevices, catching one is no easy feat.
24. Black Blister Beetle
These little guys are quite often mistaken for ants, but they’re quite a bit different.
Aside from their black appearance, they can be differentiated by their tan or yellowish coloration along the edges of their bodies.
If you see one walking around your house or on your wall, it’s best to avoid it.
They are one of the types of beetles in Washington state that secrete an acidic substance that can cause blistering on contact.
Black Blister Beetles like cool, moist environments and live mostly under rocks and decaying logs.
So, if you see one outside your home, don’t worry. They’ll usually steer clear unless there’s a nice dark space nearby for them to hide in.
25. Hermit Flower Beetle
Next, on our list of the different types of beetles in Washington state, we have the Hermit Flower Beetle.
This unique beetle has a tiny, white flower on its back that only reveals itself at night.
There are only 100 confirmed sightings of the Hermit Flower Beetle, and they are usually seen around pikas.
These are small, burrowing mammals in North Cascades National Park.
They eat fungi and plants and can be found between 5,000 and 9,000 feet above sea level on Mt. Rainier.
It’s also important to note that it is illegal to disturb or take these little creatures from their natural habitat in any way.
26. Hister Beetle
This may seem like a generic title, but while Hister beetles are most commonly found in Latin America and Europe, they are native to various parts of North America.
A species called Hister quadrimaculatus (the four-spotted assassin beetle) lives on several islands off the coast of Washington.
The name is derived from their bold black-and-yellow coloration, but little else is known about their behavior or habits.
27. Jewel Beetle
When most people think of beetles, they picture one of several species you might find in a garden or house.
Garden beetles are members of one family (the Chrysomelidae) that feed on plants.
Jewel beetles, however, are members of an entirely different family (Buprestidae).
This family contains about 2,000 species—more than all other beetle families—but many are rare.
Jeweled specimens often have colors and patterns reminiscent of precious stones and gems.
You can find jewel beetles throughout much of North America; our state is home to at least 15 kinds.
While some live above ground during summer, most spend winters in large underground groups and become active again after overwintering.
28. Black Carpet Beetle
The Black Carpet Beetle is found throughout North America and is about 2 to 3 mm long.
The larvae feed on wool, hair, fur, and feathers; however, they do not typically bite humans or pets.
Adult carpet beetles attract light at night and can crawl on window sills or fly around lights.
The best way to protect your home from infestations is by preventing entry via cracks or holes around windows or doors.
If an infestation occurs, contact a professional exterminator since black carpet beetles may also threaten antique carpets.
That’s right: let sleeping bears (or beetles) lie! Please don’t touch it!
29. Knapweed Root Weevil
The Knapweed root weevil is one of the most unique types of beetles in Washington, native to Northwestern states like Washington and Oregon.
The beetle measures 2 cm (0.8 inches) long and resembles a ladybug.
However, it has a unique black-and-white coloration that separates it from other similar beetles.
Also, unlike other beetles, Knapweed root weevils spend all four stages of their life cycle underground as larvae.
The beetle is named for its primary food source: knapweeds!
30. Black Vine Weevil
This tiny beetle, measuring only about 1⁄4-inch long, is distinguished by its elongated snout.
The black vine weevil feeds on grape vines, legumes, and ornamental plants in home gardens throughout Washington state.
In addition to its unique appearance, something else sets it apart from other types of beetles in Washington state.
When disturbed by humans, these tiny critters burst into a pungent skunk-like odor!
31. Margined Burying Beetle
These little guys (the beetles, not their jaws) are very rare in Washington and are endangered.
They are so extremely rare that humans have never spotted them.
We can regard them as the rare type of beetle in Washington state! However, we can find them by searching through owl pellets.
32. Long-horned Beetle
The Long-horned Beetle is a large, shiny beetle with antennae that are about as long as its body.
It’s found mostly in Western states, including Arizona, California, and Washington.
These beetles generally live beneath rocks or under tree bark and leaves.
They eat other insects and dead organic matter; the adult beetles are long-lived.
One was collected at an Oregon site that is one and a half miles away from where it was originally banded 43 years ago!
33. Larder Beetle
The larder beetle is a cosmopolitan species that has made its way to North America through human commerce.
Larder beetles’ damage to clothing and fabrics is easily identifiable; their larvae chew on fabric, leaving little holes.
These insects are also among the types of beetles in Washington.
In addition, adult larder beetles are small, oval beetles with long legs.
They have a reddish-brown coloration and can be found feeding on pollen or around light sources at night.
34. Maize Weevil
Speaking of the types of beetles in Washington, if you’ve ever had cornworms, you can blame these guys.
The adult weevils feed on corn kernels, while their larvae eat through whole ears and destroy more than they consume.
In addition to destroying valuable crops, they are also harmful because they contaminate food stores with eggs that hatch later.
They aren’t just a problem for farmers, either: Some types infest homes to devour grain products stored there by homeowners.
Luckily, maize weevils aren’t particularly common in Washington state — but that doesn’t mean you shouldn’t take precautions against them!
35. Margined Blister Beetle
This little insect is a part of one of the most diverse types of beetles in Washington state.
The Margined Blister Beetle has expanded its range into British Columbia, where it was introduced.
Additionally, it is a long-legged beetle with black and yellow stripes, and unlike other blister beetles, it has two rows of tubercles on its back.
Though they can cause blisters if handled carelessly, they’re not poisonous to humans.
36. Blister Beetle
Blister beetles aren’t harmful to humans; their sticky secretions can easily get on your skin and cause discomfort.
The blister beetle has many colors, from browns and reds to yellows and greens.
Their bodies are cylindrical or oval-shaped, and they have three pairs of wings at different stages of development.
They’re often found in woodlands during spring and summer, where you may see them crawling around logs or stones.
In fact, after mating, some species lay their eggs right into cracks in the bark, where they’ll hatch and feed on dead insects—ideal places for baby beetles to grow up!
37. Burying Beetle
This beetle provides one of nature’s most fascinating forms of life insurance: an afterlife.
The burying beetle has a unique relationship with carrion-eating animals called septentrionalis.
If a mammal eats an animal, it’s not likely to eat a second.
Therefore, there is no need to bury it since scavengers will not consume it.
However, if that corpse contains eggs from burying beetles, those eggs will hatch and consume more food!
These beetles have evolved to fly above their victim and drop down on it before anyone else can get to it.
38. California Root Borer Beetle
Our list of the several types of beetles in Washington state isn’t complete without the California Root Borer beetle.
The adult beetle is about 2 inches long, with a shiny black body and bronze-colored wings.
The head is large and wide with bulging eyes that look fierce.
These beetles eat roots, which can be found around orchards, vineyards, and urban parks on fruit trees.
Also, they are attracted to electric lights at night and are frequently found at campsites.
While their presence doesn’t necessarily mean you have tree damage, their numbers indicate there may be an issue with your landscape that needs attention.
39. Calligrapha Beetle
This beetle is easy to spot due to its odd, zigzag-like tracks and distinctive red head.
These beetles, which can measure up to 1.2 inches long and 0.4 inches wide, are equally one of the types of beetles in Washington.
They are oval-shaped with an elongated body similar to a bumblebee’s.
The Calligrapha beetle lives in areas including wetland meadows and sagebrush grasslands, where it feeds on nectar from flowers such as thistles or scarlet gilia.
However, these beetles are rarely seen because they spend most of their time underground or inside dead logs, especially during daylight hours when predators are more active.
They only come out at night to feed on blossoms or lay eggs above the ground.
40. Case-bearing Leaf Beetle
All beetles are considered insects, but not all insects are beetles.
That’s because there are nearly 30,000 different species of beetles that live on every continent except Antarctica.
However, you probably know most beetles by their characteristic front pair of wings, which looks like a hard shell and is called an elytra.
Male case-bearing leaf beetles don’t carry around cases but instead drape themselves with leaves for camouflage.
This is especially helpful when they’re on their backs and trying to mate!
They look like dead leaves from above and won’t be bothered by predators while they’re doing so.
41. Cedar Beetle
The cedar beetle is an important biological control agent for cedar trees, native to Western North America.
The larvae feed on hemlock and western redcedar, so it is often used to eliminate non-native cedars from infested areas.
Also, it has been known to damage local crops such as vineyards by feeding on grapevines.
Furthermore, adult beetles are bright yellow, with black legs and heads, and approximately 1⁄2 inch long.
They are most active during late summer or fall and can be spotted resting on trunks or branches of trees, logs, or rocks around midday.
Don’t forget, we are still discussing our list of the different types of beetles in Washington, and we aren’t done!
42. Checkered Beetle
These reddish-brown beetles with black spots are commonly spotted on fallen trees and stumps throughout Washington.
Checkered beetles have been known to bite humans, but they typically go out of their way to avoid it.
Meanwhile, they feed on small insects like flies, mosquitoes, and spiders and will use their short antennae to smell potential prey before attacking.
These striking beetles lay their eggs underneath the bark. If you see a checkered beetle beneath a tree or stump, look for tiny holes where its larvae are hiding.
43. Clay-colored Billbug
Although it’s a beetle, it looks more like a wasp or bee with its long, needle-like mouthparts.
These insects are just 1⁄2 inch (13mm) long and feed on various plants and trees.
They often live in grassy areas where they can easily hide while waiting to ambush their prey.
Going further, Clay-colored billbugs eat small amounts of sap at a time, so they don’t typically cause much damage to trees.
However, large infestations can cause serious damage to tree roots and trunks if left untreated.
Clay-colored billbugs spread plant diseases when feeding because their mouthparts act as wounds for disease pathogens.
44. Click Beetle
Click beetles are one of the different types of beetles in Washington state.
They are aptly named due to their large mandibles (jaws) that they use to make clicking sounds.
When these jaws snap shut, a unique mechanism produces a sibilant sound.
The jaws are located at such an angle that one side overlaps the other, allowing them to click into place when they close.
Often found under rotting logs and leaves, click beetles measure between 0.8 and 1 inch long.
Their bodies are round and metallic gray or bronze, with yellow spots on each side.
Click beetles have triangular heads, long antennae, three pairs of legs, and two oval body segments separated by a thin line.
45. Dark Brown Click Beetle
Washington state has several types of beetles, including this dark brown click beetle.
Often mistaken for carpenter ants, click beetles are beetles that get their name from their ability to make a snapping noise when disturbed.
Found all over America, in Washington state precisely, you can find four species:
- Golden-backed click beetle (Limonius auriceps)
- Dark brown click beetle (Limonius pustulatus)
- Pacific Northwest click beetle (Agriotes lineatus) and
- Valley elderberry longhorn (Desmocerus palliatus).
While they aren’t harmful, they do have a foul odor—imagine rotting fish mixed with dirty feet—to fend off predators.
To avoid getting bitten or stung by one, be sure not to handle them or get too close.
