Wheel bugs are fascinating insects known for their unique appearance and beneficial role in the ecosystem. These large, distinctive-looking bugs get their name from the cog-like toothed wheel on their thorax, a structure unique to their species in Illinois and the U.S. source. They play a crucial role in controlling pest populations, as they are predators that feed on other insects.
While wheel bugs are considered beneficial to have around, they are also known for their painful bite. It’s crucial to handle these bugs with caution, as their bites can be more severe than a bee sting source. In fact, a wheel bug bite has been described as much more powerful than a hornet or wasp sting, taking about 10 days to heal and leaving a small scar source.
Understanding Wheel Bugs
Wheel bugs (Arilus cristatus) are distinctive insects known for their unique, cog-like structure on their thorax. They can be quite large, measuring between 1 to 1-1/2 inches long, with a light gray to grayish-brown color. The most notable feature is the “wheel,” which has 8-12 teeth or tubercles 1. These insects have thin, rusty brown antennae and front legs adapted for capturing prey 2.
Distribution and Habitat
These insects are widely distributed and can be found throughout the United States 3. They are commonly found in various habitats, such as forests, gardens, and fields, where they prey on other insects, including ants, beetles, and aphids 4.
The lifecycle of a wheel bug consists of several stages, from eggs to nymphs, and finally, adults. Female wheel bugs lay clusters of eggs, which eventually hatch and release nymphs 5.
Nymphs undergo several instar stages, progressively growing larger and developing their characteristic “wheel.” They change color during this process, initially appearing red and transitioning to a cryptic gray 6.
Wheel Bug Bites
Why Wheel Bugs Bite
Wheel bugs, or Arilus cristatus, are a type of assassin bug that prey on pest insects to feed themselves. Though helpful for controlling pests, they tend to bite humans when they feel threatened or are mishandled. A wheel bug bite can be more painful than a hornet or wasp sting. It’s important to treat their bites with caution, especially when dealing with children.
Some common symptoms of a wheel bug bite include:
- Painful sensation at the site of the bite
- Redness and swelling
- Itching and irritation
- Hives or welts
In some cases, individuals who are allergic to insect bites and stings might experience anaphylactic shock. This could be a life-threatening situation and requires immediate medical attention.
When bitten by a wheel bug, consider the following treatment options:
- Wash the wound: Clean the area with soap and water to reduce the risk of infection.
- Apply a cold compress: This helps to minimize swelling and pain.
- Use a topical cream: Apply a hydrocortisone or antihistamine cream to alleviate itching and inflammation.
If the symptoms worsen or an allergic reaction occurs, seek immediate medical help.
An overview of wheel bug bites:
|Wheel Bug Bite
|Threatened or mishandled wheel bugs
|More painful than a wasp or hornet sting
|Pain, redness, itching, swelling, hives
|Washing, cold compress, topical cream
Remember to handle wheel bugs carefully to avoid getting bitten, and seek medical help if the symptoms worsen or an allergic reaction occurs.
Wheel Bugs and Your Home
Wheel bugs (Arilus cristatus) are members of the Reduviidae family, known as assassin bugs. They are beneficial insects that prey on other pests like flies. However, these bugs can occasionally venture indoors and infest homes, especially in areas like Florida, where they are more prevalent. Despite being helpful for controlling pests, wheel bugs can deliver a painful bite, making them unwanted visitors in residential spaces.
When found indoors, it’s essential to address wheel bug infestations with caution, as their bites can be more severe than a bee sting. Proper pest control and preventative measures can help reduce the risk of an infestation.
To prevent wheel bugs from entering your home, consider implementing the following strategies:
- Seal Cracks and Gaps: Check for cracks and gaps around doors and windows. Seal them using caulk or weatherstripping to deter these pests from coming in.
- Install Screens: Ensure all windows and doors have well-fitted screens to keep out wheel bugs and other insects.
The table below gives a brief comparison of two prevention methods:
|Effective in keeping insects out
|Can be time-consuming
|Allows airflow while blocking bugs
|May require professional installation
Addressing wheel bug infestations often requires a balanced approach, as they are beneficial insects. Limiting the use of insecticides and pesticides can help maintain their positive impact on controlling other pests while taking proactive steps to keep them out of your home.
Ecological Role and Benefits
Wheel bugs, also known as assassin bugs, are beneficial insects that serve as predators in the garden. They are known for hunting various arthropods, especially soft-bodied insects such as caterpillars and moths. With their piercing, sucking mouthparts, they easily catch and consume their prey. It’s important to understand their predatory behavior, as this knowledge can assist in utilizing them as beneficial insects for garden pest management.
Examples of wheel bug prey:
- Soft-bodied insects
Benefits to Gardens
Wheel bugs are valuable predators in gardens due to their appetite for many common pests, such as stink bugs and bees. Specifically, they have been known to prey on the brown marmorated stink bug, which has been an increasingly persistent problem for gardeners. Additionally, these true bugs can help keep populations of unwanted insects in check, promoting an overall healthier environment for your plants.
Key benefits of wheel bugs in gardens:
- Prey on a variety of pests
- Help control stink bug populations
- Support healthy plant growth
Comparison table: Wheel Bugs vs. Brown Marmorated Stink Bugs
|Wheel Bugs (Assassin Bug)
|Brown Marmorated Stink Bugs
|Gray, 1.0 – 1.25 inches long
|Brown, 0.5 – 0.6 inches long
|Red and black, with a distinctive cogwheel-like structure on their back
|Brown, marmorated color pattern, with a shield-shaped body
|Harmful to Garden
|No, they are beneficial predators
|Yes, they feed on plants and can cause damage
|Yes, they can overwinter as adults
|Yes, they can overwinter as adults
|Pest Management Role
|Beneficial predator, helps to control pest populations
|Pest, can cause plant damage and requires management
By understanding the ecological role and benefits of wheel bugs, gardeners can harness their predatory behavior to maintain a healthy and thriving garden ecosystem. Their presence has positive effects, such as the reduction of stink bug populations and damage to plants. Remember to appreciate the wheel bugs in your garden and the important contributions they make!
Assassin Bug Family and Related Insects
Assassin Bug Family
The Assassin Bug family, also known as Reduviidae, is a group of insects that are primarily predators of other insects. One of the most well-known members of this family is the wheel bug (Arilus cristatus). Wheel bugs are large, distinctive-looking insects with a prominent cog-like toothed wheel on their thorax. These insects are important predators of forest insects and provide valuable pest control services in gardens and yards.
Examples of other insects in the Reduviidae family include:
- Kissing bugs
- Masked hunters
Kissing bugs are known for transmitting Chagas disease, which can be harmful to humans. On the other hand, masked hunters prey on household pests like bed bugs and cockroaches.
Other Insects in the Hemiptera Order
The Hemiptera order encompasses a wide variety of insects, including wheel bugs and other assassin bugs. This order is composed of over 80,000 species of insects, with some being wingless while others having wings. Examples of insects within the Hemiptera order are:
- Scale insects
- Stink bugs
These insects are characterized by their piercing and sucking mouthparts, which allows them to feed on plant sap, other insects, or even vertebrates like birds and reptiles.
|Gray, cog-like wheel on thorax
|Tiny, pear-shaped body
|Role in Ecosystem
When dealing with pest insects in the Hemiptera order, using insecticides can be effective. However, it’s important to remember that beneficial insects like wheel bugs and other assassin bugs can also be affected by these treatments. Therefore, it’s crucial to ensure that pest control methods do not harm beneficial insect populations.
Over the years, our website, whatsthatbug.com has received hundreds of letters and some interesting images asking us about these insects. Scroll down to have a look at some of them.
Letter 1 – Bug of the Month November 2010: Wheel Bug
What is this bug
Location: Pittsburgh, PA
October 25, 2010 8:41 am
It was outside our work. Looks prehistoric.
Giant Stink Bug?
Location: Pittsburgh PA
October 25, 2010 1:28 pm
I took this photo yesterday (10/24/2010) of a large bug in my driveway. This is in SouthWestern Pennsylvania which is under a stink bug assault right now. The funny thing is several others at work have seen this bug just this weekend. One person brought in the same thing but it was entirely black instead of brown colored. We’ve called it the ”stink bug queen” and ”mutant stink bug” but really have no idea. What is this?
We have gotten so many requests in the past week to identify Wheel Bugs that despite it being chosen Bug of the Month in November 2008, we felt it warranted receiving the title again this year. The Wheel Bug, Arilus cristatus, is the largest Assassin Bug in North America. They are slow moving predators, and though they are capable of biting, we receive very few reports of people being bitten even after handling Wheel Bugs. Many people describe the Wheel Bug as looking prehistoric or comparing them to dinosaurs, particularly the Stegosaurus. In the spring, we get numerous identification requests for Wheel Bug hatchlings that look like red and black ants clustered around the remains of the egg mass that has passed the winter attached to a tree branch or fence post.
Letter 2 – Immature Wheel Bug
Help with identification, please?
Hi, I just found your site…I can’t stand bugs but this is a great idea! We’ve seen these bugs just in the last year or two here around our home. We live just across the road from the Susquehanna River, in Northeast PA (about 40 miles from the capitol of Harrisburg.) And we live near a chicken farm (with trees between us and the farm.) This photo shows what I believe to be a baby –we call them "red and black bugs". They don’t fly but live in the trees and also collect on the top rail of our fence and on the roof of the kids’ playhouse. They are sometimes found on what we call a "nest" –a kind of dark colored, low profiled honeycomb looking thing attached to the tree bark. Not sure if this is where they live or where they store their food? They grow to be at least an inch long, and if I recall correctly, the red on their tail section becomes less pronounced. They’ve got this strange red tail section that sticks up in the air. They have 3 legs down each side, 2 long antenna, and a hook-like thing at their mouth, which in the first picture is extended outward. They seem to be able to tuck it in and out whenever they want to. When they see you coming, they make evasive maneuvers to get away from you and will not hesitate to jump down to the grass from their perch in order to get away. I have seen one or two eating/carrying bugs. Also, some have a black stripe down the back of their red tail section, and some don’t have that. This particular example has the black stripe. I guess if you could tell me if they’re harmful, bite, sting etc. and of course what they’re called, I would sure appreciate it…also, what we can do to get rid of them? Or just leave them be? Thanks so much, I look forward to your reply.
What a nice descriptive letter. You hit all the points we like people to tell us regarding the photos they send. This is an immature Wheel Bug. They are predators and very beneficial in gardens and orchards. They eat many harmful insects. On the down side, they can bite painfully, but the bite is not dangerous. Just don’t handle them. Adult Wheel Bugs have wings and can fly. They have a distinctive coglike crest which alludes to the common name.
Letter 3 – Bug of the Month October 2021: Wheel Bug in nature, not in a plastic bag
Subject: Evil Black Hellbug
Geographic location of the bug: Baltimore Maryland
Time: 08:11 PM EDT
Your letter to the bugman: This hateful thing crawled into my steering wheel causing me to crash my car. In the interest of traumatizing myself again please tell me what it is so I can avoid it. Very long with a circular body part that had spiky pieces. Had to have have a mechanic take the wheel off just to get it out.
How you want your letter signed: Terrified
Franklin D. Roosevelt said “The only thing we have to fear is fear itself.” This Wheel Bug is a predatory Assassin Bug and it might bite if provoked, and the bite would likely be painful if it occurred, but it is our opinion that Wheel Bugs are relatively docile as Assassin Bugs go and they are far less likely to bite than other blood-sucking members of the family and also some less threatening relatives that are much more likely to bite, like members of the genus Zelus. We have chosen to feature your submission as the Bug of the Month for October because of your awesome subject line and your dramatic letter, and because Halloween is this month and also because we got to mention blood-sucking. However, we find your image a tad morose and though we will include the poor dead Wheel Bug in a Plastic Bag on Friday image, we suspect it was alive when you encountered it and we consider that Unnecessary Carnage. We are taking the opportunity to post once again, originally posted in 2007, our favorite image of a live Wheel Bug which many folks write to us calling a Dinosaur Bug or Stegosaurus Bug.
The mechanics kept it alive and only temporarily put it in the bag as proof they got it out.
Thank you for informing me of its stinging bite, I stayed up all night researching it and closed mouth crying.
Hello again Terrified.
Thanks for letting us know. We will remove the Unnecessary Carnage tag. You have some pretty thorough mechanics for them to have gathered the evidence of the extenuating circumstances that led to your unfortunate accident.
Letter 4 – Bug of the Month October 2021: Wheel Bugs Mating
Subject: Wheel Bug
Geographic location of the bug: Cut N Shoot Texas
Time: 03:24 PM EDT
Your letter to the bugman: This wheel bug mating was found on my back porch. Did not know what they were until I found your site. Thank you!
How you want your letter signed: Thank you
We must thank you for cheering us up with your kind letter, and also because though we do not believe your image documents typical Wheel Bug mating, we are nonetheless thrilled to post it. Probably the greatest reason your letter cheered us is that we just made a Wheel Bug posting Bug of the Month for October, but there is no reason we cannot add a second Bug of the Month posting for October, but with a more positive outcome for the Wheel Bugs.
Thank you, that was a strange bug!! And its not typical? I don’t know much about bugs, lol. However i did see one more picture of that bug with two of them on its back and it was called something like a mating frenzy haha.
Letter 5 – Immature Wheel Bug
In Georgia – Black with Red Back
Mon, Jun 1, 2009 at 5:35 PM
I have never seen this insect here in Georgia before. Image attached.
This is an immature Wheel Bug, one of the Assassin Bugs. In the spring, we often get identification requests for hatchling Wheel Bugs which resemble ants and stay in a group, and beginning in mid summer, photos of adult Wheel Bugs will begin to appear in our mail. Your photo is of an older nymph that has ventured from its siblings. Wheel Bugs can bite if provoked, and the bite is painful, but they are advantageous predators.
Letter 6 – Wheel Bug bites woman in North Carolina
Subject: got stung by this bug
Geographic location of the bug: southeastern coast of NC
Time: 06:34 AM EDT
Your letter to the bugman: I believe I got stung by this insect. I had left my drink on a fence post outside when I got it back and was holding it felt a severe burn iui n sting and only got a short glimpse of the insect I saw this guy on my front porch yesterday and was sure this met the color and size(pretty big) of the culprit. My sting is still slightly swollen painful and itchy after a week.Do these guys sting?
How you want your letter signed: Melba
Wheel Bugs do not sting, however we frequently caution our readers to handle Wheel Bugs with caution as they might bite, though unlike other Assassin Bugs, we rarely get reports of actual bites from Wheel Bugs. Though the bite of a Wheel Bug is not considered dangerous, the local effects of a reportedly painful bite might last some time.
Letter 7 – Immature Wheel Bug
Some kind of Leaf Footed Bug?
Sun, Feb 8, 2009 at 11:55 PM
I’ve found the attached bug on one of my rose bushes and on a pine tree. I can’t seem to figure out what kind of bug it is. Any help would be most appreciated.
Thanks in advance!
Often the identification of immature insects can be very difficult and your specimen is a nymph. It is not a Leaf Footed Bug, but rather an Assassin Bug. We are relatively certain this is a Wheel Bug, one of the larger Assassin Bugs that is quite distinctive as an adult because of the coglike “wheel” on the thorax that is not evident in the nymph. Assassin Bugs are beneficial predators, but they will also bite humans if mishandled, and the bite is quite painful.
Letter 8 – Immature Wheel Bug
Subject: black and orange scorpion looking spider
Location: east coast of Pennsylvania
July 10, 2014 2:56 am
This spider was on my husband. When I went too get him off, the spider actedas if it wants to fight me. Its orange under butt, curled upwards like a scorpion tail does. Also the antennas parted and acted like swords to fight me. What is it? ??
Signature: Michelle Troxell
This is an immature Wheel Bug, and though they are not considered aggressive, they will bite if provoked or carelessly handled, and the bite is reported to be quite painful.
Letter 9 – Dinosaur Cricket is actually a Wheel Bug
Subject: Dinosaur Cricket or what?
Location: Fayeteville, PA
November 5, 2013 10:19 am
My picture’s don’t clearly show the black sparkly tar like oval (I call her ”eye”) on the back of her wings. We watched her lay eggs, maybe? 2nd picture (blurry – sorry – I was freaking out about being that close to her), shows some of the shiny ”eggs” (I’m assuming they are eggs) she put on the post. Do you know what this is? If you need more pictures, and can promise me this thing just looks mean (but very cool!), but really isn’t, I can take more. It moved to a log on the porch, and hasn’t moved for days. My guess, she is still there. I avoid bugs, but this thing is just too interesting to not try to find out what it is. First saw her on Halloween. We live at the top of a mountain, along Michaux State Forest, and now she does too.
She looks like a stink bug/cricket combo that I’ve nick named dinosaur cricket.
Thank you for any information you can provide!
We love that you have named this native, predatory Wheel Bug the Dinosaur Cricket. Wheel Bugs are Assassin Bugs and they are in the same insect order as Stink Bugs. Wheel Bug Eggs are laid in a regular, geometric mass that resembles barrels.
Thank you for your response! That is exactly what she is!! With this new information, I can get more pictures of her and her glistening black “eye” on her wings. She didn’t lay a whole lot of eggs, but I hope to see more wheel bugs in the future, so I will be watching her eggs in the spring.
I think this is the first time I’ve ever thought a bug was cool, and happy it was on my porch.
It is the closest thing to a “dinosaur” that I ever want to see. 🙂
Thank you again!
Letter 10 – Immature Wheel Bug
Subject: insect on pecan tree May 2015
Location: southeastern North Carolina
June 2, 2015 7:09 am
Please tell me what this insect is.
Can it cause damage to the tree or its nuts?
Signature: Tom Maloy
This is an immature, predatory Wheel Bug, and it is a beneficial insect that will help to naturally control pestiferous species that may compromise the health of your tree, potentially increasing the number of nuts produced.
Thank you so much, I didn’t kill the bug and I will watch for them in future.
Letter 11 – European Hornet attacks Wheel Bug
A few months ago by using your website I was able to identify a mysterious bug I had never seen before sitting on my basil planter outside as a nymph wheel bug. Well, here we are a month or so later without having seen the wheel bug and we walk outside and find the now “adult” wheel bug sitting out on our deck right before we watched it get attacked and killed by a (European hornet?). Please identify the bug attacking the wheel bug in the attached picture. Thanks for your help!!!
Dear B & D,
Your identification of a European Hornet, Vespa crabro, attacking a Wheel Bug is correct. According to BugGuide, the European Hornet is : “Predatory on other insects, used to feed young. … The workers capture insects, bringing them back to the nest to feed the brood. Workers need more high-energy sugary foods such as sap and nectar, and hornet larvae are able to exude a sugary liquid which the workers can feed on.”
Letter 12 – Flattened Wheel Bug
big strange bug
First I am very sorry but I do not like bugs. I am honestly afraid of them. They give me the chills. I found this crazy bug on the top of my chair. It looks like a saw on its back and honestly a little prehistoric. It resembles some sort of stink bug. It is rather large. Atleast on my bug standards. lol Thought you may know what it is.
Your poor flattened Wheel Bug was a beneficial predator in your garden before meeting with an untimely demise. In your defense, they will bite painfully if provoked.
Letter 13 – Blurry Wheel Bug
and the 2nd pic…what is this creapy looking guy ? an assasin bug ?
Your blurry photo is of a Wheel Bug, a type of Assassin Bug.
(09/11/2004) better pics of my blurry bug
Thanks so much Patrick. Now our readers will be able to identify their own Wheel Bugs. Your photo shows off the cog-like crest nicely.
Letter 14 – Beautiful Wheel Bug Photo
Hi, I submitted this photo a couple of times but haven’t seen it posted yet. I think It is a pretty good pic. for the species (ASSASSIN). in consideration that you may be quite occupied and may have possibly overlooked it I am making one more attempt. this little guy flew in and paid me a visit on my front porch just as the sun was about to go down here in East Tennessee. Thank you for a wonderful site, It is very Informative as It Is where I learned these little creatures can be quite vicious to bug and man alike.
Jerry D. Wright / Harriman,Tennessee
We appreciate your patience and persistence. Your Wheel Bug photo is indeed quite spectacular. It is actually quite romantic. As a point of clarification, Wheel Bugs are not vicious, and will not attack you, but the bite is quite painful.
Letter 15 – Freshly Metamorphosed Wheel Bug
Great photo of a colorful unknown bug
I sincerely thank you for the most fantastic insect site on earth. You have helped me identify many bugs through all the great pics. I can not find this bug that was found on an enclosed porch in Dayton, Ohio. USA. Thanks in advance for your assist in the I.D. of this colorful bug.
Hi Again Terry,
Yesterday we wrote you a quick reply identifying your insect as a newly metamorphosed Wheel Bug, one of the Assassin Bugs. We have been thinking about your wonderful image, and wanted to post it. Sometimes time will not permit us to post everything we want to post, but we needed to revisit your submission. Many years ago, we received a similar, though very blurry photo. Your photo is so crisp and sharp and shows the orange coloration of the newly metamorphosed Wheel Bug as well as the black discarded exoskeleton. The orange color will soon darken. This Wheel Bug is still not mature. When it becomes an adult, it will have fully functional wings as well as the signature coglike wheel on its thorax.
Letter 16 – Bug of the Month November 2008 – Wheel Bug
LARGE PREHISTORIC BUG WITH SAWBLADE HEAD!!!!!
Sun, Oct 26, 2008 at 2:29 PM
Hello!! I live in Western PA, right outside of Pittsburgh and I happened to look out of my window and saw this HUGE bug walking acrossed my fiance’s roof of his truck. So we ran outside to get a closer look and he was able to snap the attached photos. It is brown, but marked like a leaf, and its backside actually curved up on the sides like an old Cadillac!! But the most interesting part was the top of his head actually resembled a tiny circular sawblade sticking out of it!! It is 5 days before Halloween and that was just too freaky for me!! lol…..can you please help us identify this? We have checked all over the internet!
Spooked in PGH
Hi, I’m sorry….I recently wrote to you regarding a large bug on our truck roof. i forgot to tell you that this thing was close to 2 inches long. It was not small bug!!! Thanks! Didn’t know if that would help you or not!!
Prehistoric is a word that is frequently used by our readers to describe a Wheel Bug. Your letter is so delightful and descriptive. The Wheel Bug, Arilus cristatus, is one of the largest and most distinctive looking of the Assassin Bugs. They are predators and they are beneficial in the garden, but like all Assassin Bugs, they are capable of biting a hapless human and the bite is painful. You can read more about the Wheel Bug on BugGuide. It is the time of the month to select our Bug of the Month for November, and since we will be leaving town for a few days before the first, we have decided to select our winner from the pool of likely candidates early. Congratulations, your image of a Wheel Bug will be prominently featured at the top of our homepage for the entire month of November. Speaking of candidates, it seems we can’t rip our eyes from the news coverage lately, and your state has been so prominently featured. We can’t help but wonder if you have been cheering and waving signs behind one of the presidential or vice presidential hopefuls.
Tue, Oct 28, 2008 at 11:59 AM
about 2 inches long found in Peru Indiana on oct 25
Indiana , USA
Your letter doesn’t have much information, but we are adding your photo to our Bug of the Month for November 2008, the Wheel Bug.
Letter 17 – Immature Wheel Bug
six legs, scorpion end, black & red/orange, walks like a walkingstick
Fri, Jun 26, 2009 at 5:36 PM
This is my first submission of a picture to you, I think. Though I have used your site for years. Thanks! 🙂 We live in West Lafayette, Indiana and we found this bug on June 26th, 2009. We took several pictures – do with them what you like. I found this bug crawling up the side of an interior door frame in our house. At first glance, I was sure it was a spider. Then I could only find six legs and two long antennae. I also thought of a scorpion as its rump went up in the air. The way it walked reminded me of a walkingstick or praying mantis. It was black and bright red/orange. We tried to take pictures of it inside, then finally took it outside and got a few shots.
Please, do you know what kind of bug this is?
Thanks! 🙂 -Anne
West Lafayette, Indiana
This is an immature Wheel Bug and it is one of the Assassin Bugs. Most Assassin Bugs are beneficial predators, but they are also capable of biting painfully if mishandled.
Letter 18 – Mating Wheel Bugs bite the Mrs.
this stung my wife
Location: SE PA woods
August 27, 2010 5:08 pm
AND NOW LIVES UNDER A CUP IN THE BACKYARD
This is a they and they are mating Wheel Bugs. Wheel Bugs do not sting, but rather, they bite, and the bite is reported to be quite painful, but not dangerous. You should release them from their cup as they are important predators that will help keep the population of plant eating insects in check.
Letter 19 – Immature Wheel Bug
Spider? Stink Bug?
Location: South Florida. Pompano/Margate area
March 12, 2011 6:37 pm
This little critter kept coming to visit a photography class we were having. It looked like a spider, except for the rear end, which was held up like a scorpion holds it’s stinger. One of the staff at the park told us this was a stink bug, but I don’t really see a shield shape.
Thanks for any help you can give me in identifying it.
This one was located in Pompano Florida at Fern Forrest Nature Center.
This is an immature Wheel Bug, Arilus cristatus, and when it is fully grown, it is North America’s largest Assassin Bug. When fully grown, it is easily distinguished from any other Assassin Bug by a coglike projection on the thorax. You can find numerous images of adult Wheel Bugs on our website, including this example dating back to October 2009. Wheel Bugs and Stink Bugs are both True Bugs in the suborder Heteroptera, so your observation has merit. Additionally, Wheel Bug hatchlings, like this grouping sent this past January, are frequently mistaken for Spiders. Wheel Bugs are one of our Top 10 identification requests, though upon viewing that tag, we realize that we have not added any new images of Wheel Bugs in years.
Letter 20 – Immature Wheel Bug
What is this ?
Location: Pool Cage – Tampa FL
April 15, 2011 1:24 pm
A friend told me of your site. Trying to identify this spider like bug in my yard. It is near my pool cage. We have never seen them in the 7 years living here. We now have had 8 over the last week. One of them stung my girlfriend on the wrist when she was sitting on the ground. It looked like a small puncture mark. She then had some aching and throbbing of her veins in her wrist. Then she has some discomfort extending up her arm. So, it seems like there is venom. BTW – we live in Tampa FL. Our house does not back into the woods. It is a settled neighborhood and we have houses on all sides of our property. I have spray some concentrated bug killer around the pool cage, but we are still seeing 1-2 per day. Today I killed 2 and I’m going to try seeing if I can find a local exterminator company that I can bring one that I captured in a jar. Any help from you is much appreciated!
Because Wheel Bugs, Arilus cristatus, have recently hatched in many parts of their range, people are beginning to request identification information. We have posted at least four letters with images of immature Wheel Bugs in the past week. Your letter contains information about your girlfriend being bitten, and we have indicated that we rarely receive reports of people being bitten by Wheel Bugs, but that there is a possibility it will happen. Wheel Bugs are beneficial predators and we would urge you not to spray needless pesticides. We are linking to an image on BugGuide of a Wheel Bug feeding on prey so that you can see the piercing and sucking mouthparts. We are preparing your letter and image in advance to post live during our absence from the office for several days next week.
Letter 21 – Immature Wheel Bug
Weird texas bug
Location: Houston, Texas
April 18, 2011 6:26 pm
I live in NE Houston, Texas, and I have an organic garden. I found this insect on a cucumber plant after having the sprinkler on for an hour or so, so I’m not sure if he was there seeking cover, or he is a pest on the cucumbers. I would like to know if it is a pest, or potentially beneficial, or neutral, I hate picking bugs off plants when I don’t know what they are!
This is an immature Wheel Bug nymph. We have posted numerous images of immature Wheel Bugs in the past few days, and they have all been submitted from Florida. Wheel Bugs are found in many parts of North America. They are beneficial predators and you should return this individual back to your organic garden.
Letter 22 – Another Wheel Bug Ménage à Trois
Is this a giant stink bug?
Location: Clarksville, MD
September 29, 2011 12:51 pm
We have quite a few stink bugs around our house this time of year (Clarksville, MD) and I found this one that resembles stink bugs though perhaps isn’t related? It is actually a large bug with a diamond-esque back with two smaller (though still large!) ones attached to its back. Pretty amazing, actually. Please let me know what this bug is!
These are Wheel Bugs. They are members of the Assassin Bug Family Reduviidae in the suborder Heteroptera. Stink Bugs are also Heteropterans, however, they are in the family Pentatomidae. This is the second image of three Wheel Bugs attracted to one another that we have received in the past week.
Letter 23 – Immature Wheel Bug
IDK what it is
March 22, 2012 9:41 pm
It was found in tampa Florida in march on a car
Signature: Andrew W
WE have no shortage of Wheel Bug photos in our archive, but we cannot resist adding your photo to our site because of its dramatic simplicity. Wheel Bugs are Assassin Bugs and they might bite if carelessly handled.
Letter 24 – Wheel Bug bites Blonde!!!
Subject: Bug bites coworker!
Location: Western PA
June 26, 2012 10:02 am
My coworker came in screaming that an alien bug with ’tentacles’ (antennae) bit her while she was outside on her lunch, it got into her short sleeves. She snapped a photo, we have been searching online to no avail. Western PA, length about an inch, 6 legs, rears up in defense when approached. kinda cool!
Signature: blonde girls
Dear blonde girls,
This is an immature Wheel Bug, and we always warn folks to handle them with caution since the bite is reported to be quite painful, though not dangerous. Thanks for your letter that supports our warnings. We just posted a photo of an adult Wheel Bug, the largest North American member of the Assassin Bug family. Assassin Bugs, including Wheel Bugs, are predators that use their piercing proboscis to suck the fluids from their prey. Hapless humans might also be bitten though this is usually an accidental encounter, like your coworker, or a case of careless handling.
thats terrific! thank you for your repsonse, I was leaning towards wheelbug for most resembles, but it didnt have all the characteristics yet!!!
Letter 25 – Immature Wheel Bug
Subject: It’s Bugging Me
Location: Eastern Sequoyah County, Oklahoma
June 22, 2013 7:41 pm
I have always liked bugs… mostly the pretty ones, but I find them all interesting nonetheless. I have never seen this creepy little critter before and this year I have them all over my yard. They seem to especially like my mimosa tree. I live in eastern Oklahoma and I think I started noticing them around the beginning of June. I’ve asked several of my friends and none of them seem to know any more than I do!
Thanks for your help!
This predator is an immature Wheel Bug. We wonder what insects are coming to your mimosa to attract so many Wheel Bugs. We suspect the mimosa may be in bloom and attracting pollinating insects.
Letter 26 – Wheel Bug
Subject: Prehistoric looking thing
Location: Allegheny County, Western Pennsylvania
October 18, 2013 8:10 am
At first glance I thought this was a spider, but on closer examination it only has six legs.
I submitted previous request but had a typo in my email address….
Signature: Regards, Tim
We figured you were inquiring about a Wheel Bug just by reading your subject line and we were correct.
Letter 27 – Immature Wheel Bug
Subject: What is this crazy looking thing?!?! Is it some kind of new Spider?
Location: Easton, PA
June 25, 2014 7:21 pm
I was driving when this thing fell on me and I seriously almost crashed! It must have been inside the car or on the roof the whole time. It looks absolutely disgusting! I’ve never seen anything like this before. What is this?
You were startled and disgusted by an immature Wheel Bug, a beneficial predatory species of Assassin Bug that might bite if carelessly handled. We wonder if any studies have ever been conducted of the frequency of accidents caused by extreme reactions to insects, including stinging bees and wasps, that are discovered inside automobiles in motion.
Thank you for the quick reply and providing me with the details on this bug. I agree and also wonder if any studies have ever been conducted, I am curious to know.
Letter 28 – Wheel Bug bites husband in home
Subject: What kind of bug is this?
Location: Pulaski Va
October 9, 2014 10:11 pm
This bug was on my husbands back in the house he said it bit him he go my son to get it off him and the took a picture ? Will we see more in the house? What is it ? do we need to worry about the bite?
Your image lacks critical detail, but this appears to be a Wheel Bug, the largest North American Assassin Bug, a member of a family of predators. Some Assassin Bug in the genus Triatoma, which are commonly called Blood Sucking Conenose Bugs or Kissing Bugs, pose a threat to humans because they can pass on the pathogens that cause Chagas Disease, however though they might bite, Wheel Bugs are not considered to be dangerous to humans.
Letter 29 – Bug of the Month Halloween 2014: Tangled Limbs: Mating Wheel Bugs
Don’t Lose Your Head on Halloween
Subject: Wheel bugs mating
Location: Charlottesville VA
October 29, 2014 1:34 pm
Hi – my daughter found these two (very slowly) making their way across the sidewalk. I checked your site right away and was expecting to spend some time trying to narrow down what they could be. I was happy to find that this was one of the featured bugs on the front page of the website. Thank you for that! Not sure if you needed any more pictures of them mating, but here are a few my daughter took with my phone.
Your study of mating Wheel Bugs is a tangle of limbs that would make a novice bug watcher suspect a sighting of some prehistoric, mutated creature. This is a Perfect Halloween Feature, so we are making it the Bug of the Month for November 2014 and posting it early. We wish you had a camera angle that could distinguish actual mating with mere coupling.
That’s terrific! My daughter will be ecstatic. Here’s another picture, but I’m not sure it gives you anything more to see. We were afraid to get too close, not knowing anything about them!
Thank you so much for your response. There will be a happy kid here after school today when she hears about the Bug of the Month.
Take care and keep up the good work!
We try to keep a kid friendly site, though we do write for adults. We like making kids happy.
Letter 30 – Egg Case of a Wheel Bug
Subject: Egg case on tree
Location: SE Pennsylvania
January 17, 2015 8:13 am
Can you help me identify the critter that made this egg case on the underside of a river birch twig? I am trying to learn about bugs and other beneficial insects. Do you recommend any other helpful sources?
We believe this is the Egg cluster of a Wheel Bug, a species of beneficial predatory Assassin Bug. The eggs will pass the winter and hatch in the spring. Though Wheel Bugs are not aggressive towards humans, they might deliver a painful bite if carelessly handled. Adult Wheel Bugs are quite distinctive looking. A good resource book is the Kaufman Field Guide to Insects of North America by Eric Eaton.
Letter 31 – Immature Wheel Bug
Subject: What is this bug
Location: Kokomo indiana
July 19, 2015 5:46 pm
Found this bug in Kokomo Indiana. It was carrying a hornet as young can see in the picture. Do you know what this could be?
The primary insect in your image is an predatory, immature Wheel Bug, and it is possibly that it captured and fed upon the wasp that we cannot identify because of the angle in the image, but we find it puzzling that it would carry around its prey. As Wheel Bugs have a mouth designed to suck food, they feed only on fluids and leave a dried husk as opposed to other types of predators that chew.
Letter 32 – Wheel Bug bites woman in Georgia
Subject: please identify?
Location: Atlanta, GA
December 12, 2015 9:28 pm
dear bugman, i live 30 miles south of atlanta, ga and was up in my tea olive bushes cutting & shaping so i could hang the christmas lights from the gutters. i stepped down in the pine straw and felt something bite the back of my thigh! i grabbed the back of my bluejeans where i felt the bite and tried to squish ~ it bit me again. i ran in the house and as i got out of my pants as quickly as possible, i prayed, “please Lord, let me find what bit me!” Out dropped the bug i’m sending you the picture of below. it is about and inch and a quarter in length. The bite immediately stung like a bee – but quickly spread out to about the size of a dinner plate in area . it began to swell immediately. i made a poultice of baking soda and with everything in the news about the ‘deadly kissing bug’ drove myself to the ER. UGH – 5 hours later, they couldn’t figure out what the bug was. it left a hole in my leg – i can’t tell if its blood in the hole – it didn’t bleed – or what. gives me shivers to think too much about it. here on day 3, the round area of swelling had gone down but is back and now a rather odd shaped oblong patch that is beginning to itch terribly. i have an appointment in a week to have a blood test for changas but in my research have come across the fact that it hurts is a good indication that it isn’t a bad bug that spreads t-cruzi but i’m looking for some bug identification… please!!!
Signature: signed, really hopeful … also known as Liz.
We are sorry to hear about your painful bite, but the good news is that this is NOT a Kissing Bug, but rather a Wheel Bug, and Wheel Bugs do not spread Chagas Disease. Though Wheel Bug identifications are among our most frequent requests, and though Wheel Bugs are the largest North American Assassin Bugs, your report is the first in over 13 years we have ever received of a person being bitten by a Wheel Bug. We have long suspected that a painful bite could result from carelessly handling a Wheel Bug, but unlike other Assassing Bugs that bite more readily, Wheel Bugs seem very reluctant to bite humans. Your unfortunate encounter was doubtless due to the Wheel Bug finding itself trapped between your jeans and your skin. Wheel Bugs are not normally aggressive toward humans. Though we do not normally provide medical advice, in our unprofessional opinion, the blood test for Chagas is probably not necessary.
P.S. We are not tagging this as Unnecessary Carnage being that it was suspected of being a Kissing Bug and having the specimen was necessary for a correct identification.
Thank you for taking your time in such a quick reply! Your answer really did help me. I wouldn’t recommend anyone else getting bitten by those little buggers for at least another 13 year! UGH.
Letter 33 – Immature Wheel Bug bites youngster
Subject: This bug bit my son…
Location: Southeastern Pennsylvania
June 30, 2016 6:36 pm
This bug was in a flower bed in New Hope, Pennsylvania. My four year-old son didn’t see it before it bit his hand. It definitely caused him quite a bit of pain and the mark was noticeable, though it didn’t seem to have any signs of venom or poison in it. It happened today, June 30, on a very warm summer evening. The bug is about an inch long, silver and orange in color, and the tail was curved upwards, resembling a stinger (almost scorpion-like). Any help identifying it would be very helpful!!
Thanks so much!
Signature: Lauren, Concerned Mom in PA
This is an immature Wheel Bug, one of the Assassin Bugs in the family Reduviidae. With the exception of Blood Sucking Conenose Bugs or Kissing Bugs in the genus Triatoma that are known vectors for Chagas Disease, Assassin Bugs are not considered dangerous to humans, however many species will bite readily. Though we often caution folks to handle Wheel Bugs with care to avoid getting bitten, we very rarely get reports of bites from Wheel Bugs. Other species of Assassin Bugs bite more readily.
Thank you so much for your quick and thorough response! It is great to know what this is and where it came from.
Have a great holiday weekend!!
Lauren Anton 🙂
Letter 34 – Immature Wheel Bug
Subject: Extinct bug ?
March 16, 2017 11:04 pm
I think i have found a very rare or uncommon bug it was on a flower pot and really freaked me out. I would really apriciate your thoughts thank you.
This Wheel Bug nymph is neither rare nor extinct. What is unusual is the early sighting during the winter in your northern location.
Letter 35 – Immature Wheel Bug
Subject: Interesting Bug
Location: North Carolina
May 24, 2017 7:56 am
Central north carolina, I thought it maybe a leaf bug, however the back is sticking up and the colors are off. What says you?
Signature: Derek sinski
You are observant to notice the similarities between this Wheel Bug nymph, and Assassin Bug, and a Leaf Footed Bug. Assassin Bugs are predators and Wheel Bugs should be handled with caution to avoid a potentially painful bite.
Letter 36 – Immature Wheel Bug
Location: Fort Wayne, IN
June 29, 2017 3:29 pm
There were two of these on my car all throughout today. Very adamant about not leaving my vehicle. When I brushed one off the butt sorta flared upwards and looked red. The photo is a little bit far but it’s a high quality photo so just zoom in a bit.
Signature: Dylan M.
This is a beneficial, predatory Wheel Bug nymph.
Letter 37 – Cog-Wheel Bug from Costa Rica
Subject: Insect Identification
Geographic location of the bug: Zarcero, Costa Rica
Time: 04:28 PM EDT
I haven’t found this guy in books or websites yet. Is it possible you know what it is?
How you want your letter signed: Charlie Doggett
Your insect bears such a strong resemblance to the North American Wheel Bug that we are quite certain it is in the same genus. Many years ago we posted an image of a mating pair of similar looking members of the genus that we tentatively identified as Arilus carinatus, but we do not know how many members of the genus are found in Central America. Right now we cannot access BugGuide to verify how many members of the genus are known. Flicker has an image of Arilus carinatus that looks very similar to your image, and we strongly suspect that identification is correct. A google book entitled Latin American Insects and Entomology by the amazing Charles Leonard Hogue has a drawing on page 223 of the Cog-Wheel Bug, Arilus carinatus.
Letter 38 – Wheel Bug bites woman in Indiana
Subject: this bug stung/bit me
Geographic location of the bug: Center Point Indiana
Time: 12:49 PM EDT
Your letter to the bugman: My husband and I went to the exotic feline rescue center to check out some big cats, while we were there I leaned on a tree and got stung bit by this bug. My hand swelled a little and I took a photo
How you want your letter signed: Jshearer
This is a Wheel Bug, the largest Assassin Bug in North America. Though we frequently warn folks not to handle Wheel Bugs, we rarely get reports of bites. Thanks for confirming our suspicions that a careless encounter with a Wheel Bug might result in a painful, but not serious, bite. We strongly suspect the bite did not occur in February in Indiana.
Letter 39 – Immature Wheel Bug
Subject: What’s this bug?
Geographic location of the bug: Upstate South Carolina, USA
Time: 09:55 PM EDT
Your letter to the bugman: Hello, I normally use iNaturalist to identify the organisms I find, but this time it is completely wrong. It is identifying this insect as a black widow but it clearly has 6 legs and is red with black dots, not black with red spots. Please can you help me identify this bug.
How you want your letter signed: Thanks, Brandi
This is most certainly NOT a Black Widow. This is a Wheel Bug nymph, and nymphs as well as adult Wheel Bugs are among our most common spring through fall identification requests from the eastern parts of North America. Though they are not dangerous, Wheel Bugs should be handled with caution as they might deliver a painful bite.
Letter 40 – Immature Wheel Bug
Subject: Bug identify
Geographic location of the bug: Baltimore, Maryland
Time: 11:42 PM EDT
Your letter to the bugman: This bug is rare
How you want your letter signed: Shay
This is an immature Wheel Bug. Wheel Bugs are not considered rare.
Letter 41 – Freshly Metamorphosed Wheel Bug
Subject: orange bug
Geographic location of the bug: apollo pa 15613
Time: 09:33 AM EDT
Your letter to the bugman : I’ve searched and very curious about this fellow. Beautiful orange color
How you want your letter signed: Joyce P
Got it!!! There was a dark grey one next to it. Thanks so much!