If you love nature, you have come across different types of beetles and are awed by their colorful elegance. Did you know each plays a crucial role in the ecosystem? Let’s explore these beautiful insects. What better way to explain this other than a beetle identification chart.
The World of Colorful Beetles
The dazzling parts of the beetle are used by different cultures in ordination for ceremonial costumes and headdresses as well as priced jewelry. The coloration of beetles is structural, in the green-blue-violet range, but red, gold, and copper colors can be produced.
How is this color produced? The epicuticle, the outermost surface, comprises stacked-up, plate-like layers. When light hits the bent layers, it’s reflected, producing different coloration.
What Does a Beetle Look Like?
Keenly observe the beetle you have identified and pick out its appearance to help you. Like other insects, beetles have a head, thorax, and an abdomen, with a hardened exoskeleton and six legs.
Size
The longest beetle, however, attains a maximum overall length of 16.7cm, which is Hercules beetle Dynastes Hercules. The smallest beetle, on the other hand, is featherwing beetle Scydosella musawasensis, measuring as little as 325 mm(12.795 in) in length.
The weight of a beetle is heaviest at its larva stage. The goliath beetle goliathus goliatus can attain a mass of at least 115g (4.1 oz) and a length of 11.5cm (4.5 in). At their adult stage, male goliath beetles are the heaviest beetle weighing 70-100g and measuring up to 11.3 cm (4.45 in).
Body
The body type of beetle dramatically varies in shape. Its Pronotum, the segment behind the head, is large and complicated.
Head and Mouthparts
The head is flexibly attached to the thorax by the cervix. It contains eyes, antennae, and mouthparts.
Mouthparts are located at the anterior end of the head and consist of several parts.
For identifying beetles, mandibles play a significant role. If you look keenly, you will notice that species that feed on plants use their mandibles to bite and chew, while predators use their pointed mandibles to capture and devour their prey.
The mandible in some species, however, is not used for food intake but for fighting between male opponents. An example is the male stag beetle.
Antennae
Antennae are highly relevant for beetle identification. Their role mostly is for sensory perception, motion detection, and identifying odor and chemical substances.
Elytra and Alae
The beetle has toughened forewings, not for flying, but for protecting the hind wings (alae) when it is resting. These wings are referred to as Elytra. Why is it critical in the identification of a beetle?
The Elytra, in most cases, covers the abdomen. However, there are different species of beetles that have a shortened elytra, partially covering the core. A good example is the rove beetle (Staphylinidae). The Elytra meets the coloration, punctures, and structure characteristic of the beetle.
In beetle identification, the alae play a crucial role. The elytra are lifted and separated during lift off. The membranous alae are unfolded and tucked under the elytra after the flight. The distinguishing factor comes in when during takeoff, the elytra are lifted a little, and the alae unfurl from the sides.
Legs
The beetle insect has its legs uniquely adapted to its way of life. Like other insects, it has three pairs of legs found at the pro-, meta- and mesothorax.
Beetles that hunt for prey have long and thin legs that make them swift while pursuing them. Dung beetles have their legs rake-like adapted for digging, and aquatic species are adapted for swimming.
What are Beetles?
You would describe a beetle as a beautiful colorful bug that is often confused with other insects. So how do you spot a beetle? Beetles are characterized by hardened wings into wing-cases, uniquely distinguishing them from other insects.
There are different types of beetles, and they constitute the order of Coleoptera (folded-wind), with about 400,000 species, making it the largest of all. The Curculionidae, which is the largest of all families, belong to this order. Thirty thousand kinds are known in the United States, and the figures are steadily increasing due to naming by taxonomists.
Their habitat is either land or water. Those on the ground can be found under rocks, vegetation in routine woods and plants, fungi, carrion, and dung. The aquatic one can be found in small puddles of water, lakes, and the great seas.
One unique beetle identification factor is that during its larval stage, it appears elongated with three pairs of jointed legs at the front of its body. They can be differentiated from the caterpillar only by having a grip on the posterior segment of its body.
The feeding habits of beetles are pretty beneficial to the ecosystem. Their food consists of dead or alive plants, so they are incredible hunters and predators while others are scavengers.
It will be great for you to identify the beetle in your garden, and a great way to do it will be using the beetle identification chart
Most Common Types of Beetles
We shall discuss the following types of beetles:
- Blister beetles
- Bombadier beetle
- Carpet beetles
- Carrion beetles
- Emerald ash borer
- Eyed click beetle
- Fiery searcher
- Fireflies
- Grapevine beetle
- Ground beetles
- Hercules beetle
- Japanese beetle
- Ladybird beetles
- Sawyer beetles
- Soldier beetles
- Stag beetles
- Striped cucumber beetle
- Ten-lined June beetle
- Tiger beetles
- Weevils
- Whirligig beetle
Blister Beetles, Family Meloidae
Blister beetles have a unique semblance to Soldier beetles and are related. They both have leathery wing covers and love the flowers during the day. They have dark blue-black color.
Blister beetles produce a body secretion that causes blisters providing them protection from predators as they become unpalatable to them. Also, its bright color (aposomatic coloration) alarms the predators away.
The Basics
Scientific Name: Family Meloidae
Size: 1 in long (25.4 mm)
Habitat: low plants and visiting flowers, often in groups
Range: Western Hemisphere
Notes: The blistering quality is for medical and recreational purposes
Bombardier Beetles, Family Carabidae
This beetle has blown away scientists due to its unique nature. In their defense against predators, they produce a particular chemical through their tails that shoot to their attacker’s face. This chemical fluid can burn you and kill insects.
The Basics
Scientific Name: Family Carabidae, in the tribes Brachinini, Paussini, Ozaenini, and Metriini
Size: less than 1 in (2.5 cm) long.
Habitat: On the ground in wild areas
Range: Worldwide
Notes: Possess one of the most influential and mind-blowing defense mechanisms
Carpet and Dermestid Beetles, Family Dermestidae
The carpet beetle is considered a nemesis to valuable collections and dead or dried-out animals. If they meet your carpet or clothes, they will devour them much as a cloth worm does. Its larvae are responsible for all the havoc.
There is a way that scientists put Dermestid to use. Since they inhabit the carcass, scientists pour Dermestid beetles into a tank and have their eggs laid on a corpse. The larvae will devour the carcass voraciously, and the end product will be a clean skeleton for study.
The Basics
Scientific Name: Family Dermestidae;
Size: Petite; usually about 1/4 in (6.35mm) in length
Habitat: Found wherever there are stored organic materials
Range: Worldwide
Notes: They are beneficial in clearing a skeleton for study
Carrion Beetles, Family Silphidae
Also known as burying beetles, Carrion beetles are from the subfamily of Silphinae and Nicrophorinae. They are known to burrow through carcasses until they fall. They will also lay eggs on that same carcass and cover it. Their presence on a corpse helps estimate post mortem interval by measuring a Silphid progeny substance.
Silphinae and Nicrophorinae differ in caring for their larvae (parental care) and their preference for carcasses. They can take flight well enough
The Basics
Scientific Name: Family Silphidae; various species around the world
Size: Medium-sized, attain up to about 1 in (25.4 mm) in length
Habitat: Carcasses are home to them
Range: North America, Asia, and Australia
Notes: they feed on dead animals, making them environmentally beneficial
The Emerald Ash Borer, Agrilus planipennis
The Emerald Ash borer beetles are very invasive to the American forest. True to their name, they are referred to as jewel beetles due to their beautiful radiance. They inhabit the bark of trees, where they lay eggs. These eggs mature into larvae which, over time, are responsible for destructions larvae, and are accountable for the destruction of a whole tree.
In Asia, its infestation is controlled by predators that feed on them. However, in the USA and Europe, these predators are absent, allowing them to multiply.
The Basics
Scientific Name: Agrilus planipennis
Size: relatively small, often less than 0.5 in (1.27cm)
Habitat: Areas with the host, ash trees (genus Fraxinus)
Range: Originally Asia; now throughout the Western Hemisphere
Notes: Its infestation is controlled by predators that feed on them
Eyed Click Beetle, Alaus Oculatus
They mainly occur in the South of America. Eyespots on its thorax characterize eyed Click beetles to scare away predators. These beautiful beetles have actual eyes that are sharp but small and hidden.
There are different types, but one common aspect is that if you flip them, they can bring the thorax and abdomen together and launch themselves up on their feet into the air.
The Basics
Scientific Name: Alaus Oculatus
Size: From 0.5 in (1.27cm) to nearly 2 in (5.08cm)
Habitat: Virtually any wild or green
Range: worldwide
Notes: There are many, many species of click beetles in the world, and they can all snap themselves into the air to escape danger.
Fiery Searcher, Calosoma scrutator
This spectacular beetle is hardly seen as it is nocturnal and swift. It is adapted for hunting and preying on other insects.
It produces a harmful fluid that smells like rotten milk when it’s cooked. You will be safe not to touch them.
The Basics
Scientific Name: Calosoma scrutator
Size: 2 in (5.08cm) in length
Habitat: Wild areas with caterpillars and other insects to hunt
Range: Eastern US
Notes: Smart use of chemical defense to escape predators.
Fireflies, Family Lampyridae
Fireflies, not flies, are charming kinds of beetles that have 2000 different species around the world.
So why are they called charming? In the US, there are different species where the female mimics the sound of another female species luring the male, only to attack it and eat it.
Fireflies have a characteristic light resulting from a cold chemical produced as they fly. In this way, they find each other for mating or eating purposes. In Eurasia and Africa, they are known as ‘glowworms.’
The Basics
Scientific Name: Family Lampyridae
Size: 1 in (25.4 mm) long
Habitat: Grass, other greenery.
Range: worldwide
Notes: Attract mates and prey using cold, chemical light.
Grapevine Beetle, Pelidnota punctata
Also known as the spotted June beetle, the Grapevine Beetle is found roving at lights in summer. Their source of food is the grapevine, hence its name. It is beneficial to the ecosystem since they cause little to no damage and are not considered a pest. There are two varieties of this species. One is found in the north (has darker legs) and the other in the south.
They quickly disperse to the air if slightly bothered. Their habitat is mostly wood, hedges, and bushy areas. The larvae will feed on decayed wood under the soil. In the pupa stage, they will mostly be found in shallow chambers. The adults will come out and fly in the warm summer.
The Basics
Scientific Name: Genus Pelidnota
Size: Attain up to 1 in (25.4 mm) in length
Habitat: Larvae (grubs) will feed on roots and habitat the soil. When in the adult stage, they feed on grapes and other plants.
Range: All through the Eastern USA
Notes: The adult beetle comes out in the summer hence their relation to the more common brown “June bug.”
Ground Beetles, Subfamily Carabinae
You may have come across black or brown-looking beetles is hastening along the sidewalk, which is probably a Ground beetle. It is found in the subfamily Carabinae, which forms a large group of beetles. Ground beetles mostly live under stones and logs, under your basil pot on the floor, or even under your porch. They are entirely harmless and benefit you by preying on pests you wouldn’t want to encounter.
They are rarely found in your home, so if you come across a bug, it’s most likely a roach. Cockroaches are entirely different from beetles, and if you have them, take steps to eradicate them.
The Basics
Scientific Name: Subfamily Carabinae
Size: Most are less than 1 in (25.4 mm)-a few are quite large
Habitat: These beetles live outside, under stones and logs, and prowl around looking for small insects to eat
Range: These beetles have a worldwide distribution
Notes: Their appearance is close to that of cockroaches but is hardly found in your home.
Hercules Beetles, Genus Dynastes
Found in the genus Dynastes these giant beetles are located in the warm tropics. The insects found in these areas are known to be among the giant insects in the world. Although the Dynastes beetles are rare in the United States of America, the eastern Hercules beetles, Dynastes tityus, are sometimes found on trees in large colonies. Despite their immense size and the males’ massive horns, they are non-dangerous.
The Basics
Scientific Name: Found in the Genus Dynastes.
Size: Attain up to 2 in (5.08cm) in length
Habitat: Larvae is found in decaying wood, while adults can sometimes be found on aged trees
Range: All through Eastern USA
Notes: They have scary looking horns but are harmless
Japanese Beetle, Popillia japonica
Despite being called Japanese beetles, they are not confined to Japan but are also found in the United States. They are considered very destructive pests in the US, ravaging through leaves of above 300 species, primarily roses, grapes, linden, and crepe myrtle. It’s regarded as one of the most beautiful beetles with copper-colored wings (elytra) and luminescence of green color at the thorax. You might mistake it for a bee due to their semblance and that it mostly hovers among flowers.
This beetle originates from Japan, and natural predators manage its population. In North America, these invasive species cause havoc due to little to no natural predators to inhibit their multiplication. In 1916, there was the first invasion of this species at the New Jersey greenhouse that left no green plant standing. Only nine states in the West are free from P. japonica.
The Basics
Scientific Name: Popillia japonica
Size: Attains about 0.5 in (1.27cm) in length
Habitat: Larvae are grubs and habitat the under-soil and consume roots for food; adults feed on leaves of more than 300 plants
Range: All through the eastern USA
Notes: They have existed in the US for about 100 years.
Ladybird or Ladybug Beetles, Family Coccinelidae
When you think of black dots on red, a ladybird (for those in Europe) comes to mind. They are small insects of many species where some love anonymity and can hardly be seen, while others are common to everyone.
Ladybug is considered beneficial in the control of aphids that kill plants. They lay eggs at aphid colonies, and the larvae spend their days eating them up.
The Basics
Scientific Name: Family Coccinelidae
Size: less than 0.5 in (1.27cm) in diameter
Habitat: all wild areas
Range: Worldwide
Notes: Beneficial for control of aphid infestations
Sawyer Beetles, Genus Monochamus
From its name, you could guess what a sawyer Caterpillar does. And yes, you are right; it saws and drills into logs and dead trees. The larvae, which appear like the tough caterpillar, are borne into dead and dying trees. They like to inhabit Conifers and pines and cause between 30 to 40 percent damage to a log due to the hole delivered by larvae.
Do not be deceived by its sharp pincers, which are very harmless. They fly off to the lights and hover there. The male is relatively small compared to the female, but its antenna makes up for that. The long outstanding antennae are sometimes twice as long as the body.
The Basics
Scientific Name: Genus Monochamus; “longhorn beetles,” family Cerambycidae
Size: Medium to quite large; some females measure over 1 in (2.54cm)
Habitat: Found wherever there are plenty of trees
Range: Throughout the USA
Notes: they not only bore holes into trees but transmit disease from one tree to another.
Soldier Beetles, Family Cantharidae
Soldier beetles are long and brightly colored with leathery winged covers (elytra) instead of the hard shell on most beetles. The taxonomists that named it looked at it, and we’re reminded of British soldiers’ redcoats. True to their soldier nature, they fly well and can be thought to be wasps, albeit harmless. You will find them buzzing in your flower garden gracefully, fooling their predators that they can sting.
The Basics
Scientific Name: Family Cantharidae
Size: Most are about 1 in (2.54cm) long
Habitat: flowers like goldenrod
Range: western Hemisphere
Notes: Soldier beetle wasps, but they are harmless
Stag Beetles, Family Lucanidae
They are chested brown or black in color beetles, with mandibles that appear like the horn of a stag deer, hence the name Stag beetles. They spend most of their adult life underground and emerge only during summer for mating.
On the ground, you will mostly find the female looking for where to lay her eggs. In the larval stage, it is found in rotten stumps and prey on insects.
The Basics
Scientific Name: It’s found in the family of Lucinadae species and the genus Lucanus
Size: grows up to 2 in (5.08cm) in length
Habitat: Rotten woods primarily for the larva; at night, the habitat the light
Range: the entire USA and the south of Canada
Notes: Has short and sharp mandibles that give a painful pinch but are not venomous.
Striped Cucumber Beetle, Acalymma vittatum
Unlike other summer-loving beetles, the Striped cucumber beetle emerges in its large numbers in the spring and heads for cucumbers. They ravage the plant to its death. As you have already guessed, it’s the larvae that do the havoc. It inhabits the plants, laying its eggs which mature to larvae.
The Basics
Scientific Name: Acalymma Vittatum
Size: 0.5 in (1.27cm) in length
Habitat: Garden, and anywhere else there are cucumber plants
Range: Worldwide
Notes: Two closely related species, the spotted cucumber beetle, Diabrotica undecimpunctata, and the banded cucumber beetle, Diabrotica balteata, are more common in Florida.
Ten-Lined June Beetle, Polyphylla decemlineata
Have you seen a showy bug near your source of light, and you come from the Southwest of America? It could be a Ten-lined June beetle. It is closely related to the grapevine beetle, and can be spotted around lights in homes in urban areas.
If you pick up a Ten-lined June beetle, it will make a sudden, startling, loud quivering buzz as a sign that it has entered its defense mode.
The Basics
Scientific Name: Polyphylla decemlineata
Size: It appears large. Attains about 1 in (2.54cm) in length
Habitat: Larvae are grubs that habitat the under-soil and consume the roots for food
Range: Worldwide
Notes: Can be spotted around lights in homes in urban areas.
Tiger Beetles, Subfamily Cicindelinae
These highly unnoticeable beetles are from the subfamily of Cicindelinae. They are known for their predatory skills and swift speed, hence Tiger. The fastest of them is called Rivacindela hudsoni. They have long thin legs, bulging big eyes, and large curved mandibles.
They display a nervous demeanor where they fly and land 5 feet away when you get too close to them or follow them. The sudden stop is to help them visually reorient since they move too first to process images accurately. One amusing thing is that when the beetle is moving, it holds automatedly onto its antennae to sense its environment. You can find them in sandy areas sidewalks during summer.
The Basics
Scientific Name: Subfamily Cicindelinae, Family Carabidae;
Size: Attains 0.5 in (1.27cm) in length
Habitat: Summer weather, flat surfaces and hunt, and prey on other insects
Range: All through the USA, even deserts
Notes: Species in this group are slightly distinguished, making it hard even for a professional to tell them apart.
Weevils, Superfamily Curculionoidea
These beetles are arguably the most successful insects as they are subtle as they invade your grains in your pantry. Weevils can drill a hole in your dried corn but be very harmless to you. There is, however, the ‘boll’ weevil which can get onto cotton and destroy its fibers rendering it useless.
They are from the subfamily of Curculionoidea and are characterized by a long snout. They love the warm temperatures, and a diverse range of them is there.
The Basics
Scientific Name: Superfamily Curculionoidea
Size: Small-to-medium-sized beetles, Attain up to about 1 in (2.54cm) length
Habitat: Found just about everywhere; they have adapted to nearly every corner of the world
Range: Worldwide; possibly also on the moons of Jupiter
Notes: They can adapt to the food and conditions of virtually any environment
Whirligig Beetles, family Gyrinidae
The Whirligig beetle is an aquatic beetle, which can also be found in a puddle of water in your backyard. They love to spend their time in pools as a colony. When this dark-looking beetle is disturbed, you will see it zig-zagging and going in circles in the water as it causes havoc. Their slick and flat surface helps them escape predators
They love the summer, and you will be amazed when you observe the wiggling in their numbers in the water.
The Basics
Scientific Name: Family Gyrinidae
Size: Small to medium 0.13 in (3mm)
Habitat: Found wherever there is still water
Range: Throughout the USA
Notes: Although they spend most of their time on the surface, whirligig beetles will dive if they feel especially threatened
A Common Beetle Identification Chart
IMAGE | NAME | SCIENTIFIC NAME | RANGE |
Blister beetles | Meloidae | Western Hemisphere | |
Bombardier Beetles | Carabidae | Worldwide | |
Carpet Beetle Dermestidae beetle | Dermestidae | Anywhere there are organic foods | |
Carrion Beetles | Silphidae | North America | |
Emerald Ash Borer | Agrilus Planipennis | Western Hemisphere | |
Eyed click beetle | Alaus Oculatus | Worldwide | |
Fiery searchers | Calosoma scrutator | Eastern US | |
Fireflies | Lampyridae | Worldwide | |
Grapevine | Pelidnota punctata | Eastern USA | |
Ground beetles | Carabinae | worldwide | |
Hercules beetle | Dynastes | Eastern USA | |
Japanese | Popillia japonica | Eastern USA | |
Ladybug/Ladybird | Coccinelidae | Worldwide | |
Sawyer | Monochamus | USA | |
Soldier | Cantharidae | Western Hemisphere | |
Stag beetles | Lucanidae | USA | |
Striped Cucumber beetle | Acalymma vittatum | World wide | |
Ten-lined June | Polyphylla decemlineata | South Eastern USA | |
Tiger | Cicindelinae | USADeserts | |
Weevils | Curculionoidea | Worldwide | |
Whirligig | Gyrinidae | USA |
Step-by-Step Instructions for Identifying a Beetle Insect
These are the methods of identifying a beetle;
- Identify beetle’s basic features
- Identification of large beetles
- Identification of small beetles
Method 1 of 3
Identification of beetle’s basic structure
- Observe and point out if the insect has a covering of 2 rigid wings (elytra) on its back. This hard covering is why the beetle will produce the grating sound.
- If you find an insect with wings, that may not be a beetle. A beetle’s wings are not visible unless the elytra are lifted.
- Look out for the mandibles below the mouth. Different species have their mandibles adapted for their unique eating habits. Check if their mouthparts are sharp-looking.
- If you find the mouthparts having a long-sharp protruding appearance, you could be looking at a nectar sucking insects
- A beetle will have six legs distributed differently through its body at different stages. In their larvae location, the legs will be found on the front of their body. When you meet a mature beetle, its legs will be at the front and back segment.
- Tip: An insect with 4 or 8 legs isn’t a beetle.
Method 2 of 3
Identifying Large Beetles
- A click beetle is one of the giant beetles with a long and narrow body. Also known as Elateridae, it can flip itself back up if overturned. You will hear it make a clicking sound when it snaps the front and back parts of the body.
Suppose you spot a black or dark brown beetle with grooves down their backs that is most likely a beetle. Click beetle attains 0.5 to 1.5 in (1.3 to 3.8 cm) length.
There are over 900 species of click beetles in North America alone.
- Have you ever come across a beetle with a pungent smell swiftly moving across the ground? That is most likely a ground beetle. These black and grooved beetles swiftly move across the floor, making it difficult to spot them. You will find them under logs and leaves but can be found in your living room as they go through cracks or open windows.
Despite their speed, odor, and sharp mandibles, they are harmless and will prey on other insects for pets.
3. Look out for longhorn beetles when you are in the woods. The antennae may be straight, curved, or half and half. You will find these colorful insects around dead trees.
4. Looking for a mealworm beetle? Its head is round with a scoop neck around its base. These beetles will be found outdoors or feasting on your flour and dried grains.
5. If you come across a white-spotted winged beetle with sizable leg segments, it could be an Old house borer. It is characterized by small gray hair and three dark eyes on each side of the beetle’s mouth.
An interesting fact is that this beetle will show up 4 to 7 yrs after you’ve built your house!
Method 3 of 3
Identifying Small Beetles
- To identify a carpet beetle, look for a black body with a longer-looking abdomen. Their bodies are oval. Their size ranges from 0.12 to 0.19 in (0.30 cm to 0.48 cm). Varied color carpets are small, measuring 0.12 in (0.30 cm).
- Lookout for elm beetle tree leaves which are their food source. Their eggs are laid on the underside of leaves. Their size is 0.25 in (0.64 cm) long.
- Look out for a ladybug by their black and black over red spots. Some have yellow, orange, or red with black markings or can be black with red, orange, or yellow markings.
- You can find Larder beetles on your ham. These black beetles, with whitish, silver streaks running across their body, are known to infest cured ham.
- When preparing for a bonfire, look out for bark beetles in your firewood. They have a Cylindrical shape measuring 0.12 in (0.30 cm) long. Their infestation on live trees will lead to its death. Their infestation leads to dry, dead woods that increase forest fires.
- You can spot the drug store beetle by its color that ranges from brown to reddish-brown. Their wings have lines and have a slightly bent head. They measure around 0.1 to 0.14 in (0.25cm to 0.36 cm) length. You will find them in your packaged food. A cigarette beetle is identical to the drugstore beetle; however, it has a bent-over head and a hump.
- Have you come across a rust-colored and clubbed antennae beetle? It must be a rust beetle. They consume corn flour and other packaged products. Keep your flour in an airtight container away from pests.
- Check your rice, corn, and other grains for weevils. They have a snout-like mouthpart. These slender beetles are about 0.12 in (0.30 cm) long.
- Check out for teeth-like sides of the Saw-toothed beetle’s thorax. They measure about 0.12 in (0.30 cm) length. They consume Sunflower seeds and nuts but can also devour large grains.
Conclusion
These insects that continue to amaze us, can easily be identified! I believe this article has provided you with a clear guideline.