Ambush bugs are a subfamily of assassin bugs known for their unique appearance and hunting behavior.
These insects have hooked forelegs with widened femur sections, clubbed antennae, and a broad abdomen that extends beyond the wings’ coverage area.
Many people often wonder if the bite of an ambush bug is poisonous or not. The answer is, while they are predators of other insects, ambush bugs are generally not considered dangerous to humans.
Their bites can be painful, but they are not poisonous to humans. Usually, they don’t inject venom into humans as they do when hunting prey.
It’s important to avoid handling or aggravating these creatures, as a bite could cause discomfort and potential skin reactions in sensitive individuals.
Ambush Bugs: An Overview
Physical Characteristics
Ambush bugs are small insects with distinct physical features. They have:
- Hooked forelegs with widened femur sections
- Clubbed antennae
- A wide back portion of the abdomen that usually extends outward
These bugs are typically yellow, tan, or brown. Their jagged body contours help disguise them in their natural environment.
Taxonomy and Distribution
Ambush bugs belong to the Reduviidae family, making them relatives of assassin bugs.
The Phymata genus, also called jagged ambush bugs, is found throughout North America. These predators prey on other insects by ambushing them with their powerful forelegs.
Difference between ambush bugs and assassin bugs
Feature | Ambush Bugs | Assassin Bugs |
---|---|---|
Family | Reduviidae | Reduviidae |
Genus | Phymata | Various |
Distribution | North America | Worldwide |
Color | Yellow, tan, or brown | Varies, often brownish or black |
Forelegs | Hooked with widened femur sections | Less robust |
Jagged body contours | Yes | No |
Ambush bugs, both male and female, play essential roles in the ecosystem as predators to help control populations of other insects.
Ambush Bug Camouflage: The Masters of Deception and Predation
Ambush bugs are the masters of deception and predation in the natural environment. They use advanced camouflage techniques that baffle even the most discerning observers.
Their small size and cryptic coloration allow them to blend seamlessly with their surroundings, rendering themselves virtually invisible to unsuspecting prey and potential threats alike.
Leveraging their keen understanding of environmental cues, these insects strategically position themselves amidst flora, where their spiky protrusions mimic plant textures, thus further obscuring their presence.
With their exceptional patience and remarkable ability to remain motionless for extended periods, ambush bugs can mimic objects like withered twigs or dead leaves with astonishing accuracy.
Habitat: Floral Environment
Ambush bugs are commonly found in various environments, such as gardens, fields, prairies, and roadsides across the United States, especially during the summer months.
They often inhabit flowers and plants from the sunflower/daisy family, including goldenrods and thistles. These small yet mighty garden predators efficiently prey on insects like leafhoppers, moths, and wasps that visit flowers.
Camouflaging Techniques
Ambush bugs are experts in camouflage, easily blending in with their surrounding environment.
Their angular, greenish-yellow, white, and brown bodies allow them to seamlessly adapt to the flowers they inhabit.
As they wait for their prey, they often hold still on a flower or leaf, making them nearly indistinguishable from their surroundings.
For example:
- An ambush bug on a goldenrod flower is barely noticeable due to its camouflaged appearance.
- When hiding in green leaves, their greenish-yellow bodies help them stay concealed from predators and prey alike.
Comparison Table: Ambush Bug vs. Praying Mantis Camouflage
Ambush Bug | Praying Mantis |
---|---|
Angular, greenish-yellow, white, and brown bodies | Usually green or brown with slim bodies |
Found on flowers and plants, particularly the sunflower/daisy family | Found on various plants and leaves |
Blend in with flowers, such as goldenrods and thistles | Mimic the shape and color of leaves |
Features helping Ambush Bug Camouflage:
- Angular body shape
- Greenish-yellow, white, and brown color
Diet and Hunting Behavior
Prey Selection
Ambush bugs, being predators, primarily feed on various insects such as:
- Bees: Including honey bees and native bee species.
- Butterflies: Many small butterfly species can fall victim to ambush bugs.
- Moths: Similar to butterflies, moths can also be prey for these bugs.
- Leafhoppers: These small plant-feeding insects are part of the ambush bug’s diet.
- Aphids: As common garden pests, aphids are often targeted by ambush bugs.
- Ants: Ambush bugs can attack ants as well, although they may not be their first choice.
Hunting and Feeding Methods
Camouflage: Ambush bugs have jagged body contours and can be greenish-yellow, white, or brown, allowing them to blend in with their environment easily.
Raptorial Forelegs: Hunting is made easier with their hooked forelegs, resembling those of a praying mantis, which help them grab prey with ease.
Fast Strikes: Like other hemipterans, such as the wheel bug and kissing bugs, ambush bugs strikes quickly to kill their targets efficiently.
Injecting Venom: Ambush bugs inject venom into their prey using their long mouthparts, making it easier to consume their invertebrate victims.
Table showing the hunting method comparison between ambush bugs and other hemipterans
Ambush Bugs | Other Hemipterans | |
---|---|---|
Hunting Method | Sit-and-Wait | Active Hunters |
Prey Size | Mostly Small | Varies |
Venom Injection | Yes | Yes |
Camouflage Ability | Excellent | Varies |
Sticking mostly to a sit-and-wait method, ambush bugs rely on their camouflage and thickened forelegs to capture prey that come too close.
As their mouthparts deliver venom, the prey is immobilized, allowing the bug to consume its meal with little resistance.
Conclusion
The camouflage capabilities of ambush bugs are nothing short of extraordinary. Their mastery of deception and predation is on full display as they seamlessly blend into their surroundings, becoming virtually invisible to both prey and predators.
With keen environmental awareness, they strategically position themselves amidst flora. Their exceptional patience and ability to remain motionless for extended periods enable them to mimic inanimate objects with remarkable precision.
Indeed, these small yet mighty predators exemplify the true art of camouflaging in the natural world, elevating their hunting prowess to a level of unparalleled excellence.
Ambush Bug – Readers’ Mail
Over the years, whatsthatbug.com has received hundreds of letters and some beautiful images asking us about Ambush bugs. Scroll down to have a look at some of them.
Letter 1 – Flesh Fly gives viviparous birth to Maggots while in the death throes of an Ambush Bug!!!
ambush bug with flesh fly
Hello,
I’ve spent quite a bit of time on your site in recent months, trying to identify arthropods of all kinds. One I’ve found especially fascinating is the ambush bug–what a formidable hunter!!
Several days ago, I was astonished to find one with a Silver-spotted Skipper, quite a large catch for such a small bug. Today, spotted one with a flesh fly. My goal was a good photo of the ambush bug, not the flesh fly; unfortunately, the near constant breezes of the last week are not conducive to ultra-sharp pictures. I almost deleted the picture, but then something caught my attention. The fly, in her death throes, had given birth.
Just yesterday, in thumbing through my new Kaufman’s “Field Guide to Insects of N.A., read that some flies, including flesh flies, are viviparous. If you like, you may post the attached picture. Thanks for all you do. Between your site, BugGuide & my new Kaufman’s, I’m happily IDing most of my arthropod photographs. Sincerely,
Linda
Hi Linda,
Your photograph is quite wonderful, even though your primary objective is not as visible as you might hope. Try to remember that the excellent camouflage of the Ambush Bug is key to its success as a predator. We will be archiving your image on numerous pages, including flies, maggots, true bugs and food chain.
Letter 2 – Ambush Bug feasting of flower visiting fly
Southern Ontario Canada Bug
Bugman,
Photograph was taken at the end of August, 2005 in my backyard. Bug on the right in the photograph was ‘eating’ the bug on the left. What is the bug on the right?
Thanks,
David
Hi David,
This is a Jagged Ambush Bug, Phymata erosa. They are True Bugs in the family Phymatidae. They often sit and wait on flowers where they are camouflaged. When a bee, butterfly, or flower visiting fly like the one in your photo, comes to the flower to feed, the Ambush Bug earns its name, often capturing insects far greater in size.
Letter 3 – Ambush Bug eats Honey Bee
Flaky spotted bug thing…
Hi,
I so enjoy your site, thanks for helping me out on this one. I tried to browse your site to figure out what this was, but wasn’t even sure what to type in the query. I apologize for it being sort of cropped off, but maybe it’s enough to give you an idea.
I was out deadheading marigolds and actually saw this bug the day before. I thought it was a flaky dried piece of leaf and almost brushed it away. When I looked at it more closely, on that first day, it was actually two bugs.
The one you see in this image and a smaller “baby” piggybacking it. It just looks so surreal to me and very creepy what it seems to be doing to that poor bee! Thanks…
Marisa Longmont, CO
Hi Marisa,
This is an Ambush Bug feeding on a Honey Bee. Ambush Bugs are True Bugs that, as their name implies, ambush prey. What you witnessed the day before was mating activity.
Letter 4 – Ambush Bugs Mating
two buggy things
First off, I’m now totally hooked! Many of the killer bad bugs have been ID’d and we can breathe easier knowing they are not killer bugs after all. My kids and I have had the camera with us now whenever we go out because we never know when we’ll get a good shot.
OK, the first one is of two tiny mantis looking bugs. They are maybe 1/2 inch long, can fly, and have those praying type of front legs. We were wondering if the mantis looking bugs were in fact tiny mantis critters (hope pic is clear enough).We live in SE CT.
Thanks so much,
Erika
Hi Erika,
Your mantis bugs are Ambush Bugs, Family Phymatidae, and they are mating. They wait on flowers to ambush nectar seeking insects.
Letter 5 – Ambush Bugs: Tandem Feeding
I was surprised to see two assassin bugs working together to catch this small bee. What kind of assassins are they?
Do assassin bugs generally work together to catch insects? I have never seen this before. What kind is it? Thanks for your help. I look forward to seeing your new site. Om shanti,
Roberta Dell’Anno
Andover , MA
hi Roberta,
These are Ambush Bugs in the family Phymatidae, not Assassin Bugs. We doubt that they worked together to capture the prey. It is more than likely that one Ambush Bug caught the bee, and the other Ambush Bug is opportunistic and taking advantage of a convenient meal. Our website redesign is currently on the back burner, but eventually, you should see a change.
Letter 6 – Ambush Bugs Mating and Feeding on Eight Spotted Forrester
sharing a conjugal assassination
Wed, May 6, 2009 at 12:27 AM
Hi WTB?!!
First let me say that I love your site! I use it all the time to find out what kind of critters I come across in my random days. AWESOME! While this is not a request for identification, I thought I’d share a nifty story about my first encounter with an 8-Spotted Forrester Moth.
This was the only way to share the photos.
In March of 08 it was really windy as per usual, but I was bound and determined to take pictures of bugs. I was very excited to find a very colorful “butterfly” on one of the trees lining my driveway.
Those trees are great as they have LOTS of flowers in the springtime and attract many bees and fluttery things for me to enjoy and photo. Well this little beauty seemed to be stuck somehow and didn’t/couldn’t fly away like they normally do when I get so close. Being one to take advantage of a situation I snipped the tip of the branch and brought it inside so I could get a better, calmer view.
Imagine my surprise when I followed the tongue of my “butterfly” down through the flowers into the mighty grip of a little female assassin! WOW! It was VERRRY windy that day so she must have been holding on insanely tight!
Being as the (later identified) moth was already caught and most of the damage done I decided to let the macabre show play out and see what kinds of pictures I could get. Well they’re not quite the quality I was hoping for, but they’re clear enough to tell a story and get a point across.
In the first diptych you can see her hanging on to the tongue (left) while he takes the lion’s share (right). In the second image was the “adults only” portion of the show where she was allowed to get hers while he *ahem* “got his”. The excitement of that capture was apparently great enough that he just couldn’t wait.
And because they are so difficult to see amid the flowers the third image shows him strutting his stuff across the edge of a leaf as victor and stud.
Hope you enjoyed as much as I did. Creepy though it was, it was still way neat-o to see! the assassins were put back outside afterward to continue doing what they do.
Unfortunately 1 moth was harmed in the process of making these photos, but that’s how nature rolls!
Mary in Magnolia, Texas
South-East Texas
Dear Mary,
Thanks so much for your graphic photos and riveting first hand, eye witness account of this mating and food chain marvel. We only have one slight correction. The amorous hungry couple are Assassin Bugs, but they are in the Ambush Bug subfamily Phymatinae . It was not until we searched BugGuide that we became aware of the taxonomic change as Phymatidae was once a distinct family. Thanks for providing this wonderful cross-tagged submission.
Letter 7 – Ambush Bug eats Flesh Fly
Green thing eating a fly?
Location: Guelph, Ontario, Canada
July 25, 2010 4:21 pm
Saw this bug on a walk today. Looks like it’s eating a fly. It’s summer and I live in Ontario Canada.
Brittany
Hi Brittany,
My, this is a beautiful photograph of an Ambush Bug eating a Flesh Fly. Ambush Bugs in the subfamily Phumatinae (See BugGuide) have recently been downgraded from having their own family status to being considered a subfamily of the Assassin Bugs. Ambush Bugs wait on flowers to ambush their prey, often insects that pollinate the flowers. The fly in your photograph looks like a Flesh Fly in the family Sarcophagidae. Our own Mt. Washington, Los Angeles offices have recently been host to Flesh Flies which seem to enter when the doors are open. We find several indoors every week. Flesh Flies maggots feed on rotted meat, be it animal carcasses or putrefied meat from the market. Adults feed on sweet fluids including nectar (hence the ambush on the blossom), sap and fruit juice. See BugGuide for more information.
Letter 8 – Ambush Bug eats Bee
Ambush Bug Eating Honeybee
Location: Milton, VT, USA
June 25, 2011 8:56 am
I mentioned the Ambush Bug in my previous submission so I thought I would send you the photos of the one I saw that had ”ambushed” a honeybee in a Queen Anne’s Lace! The one I am holding is a second one that was in the next flower over.
He/she had the coolest face I’ve ever seen on a bug (except for a cicada), kind of reminded me of a dinosaur. Anyway I hope you enjoy these, and I love this site. This site kept me from killing a pseudoscorpion I found in my closet that I thought was a tick!
Signature: Betsy
Hi Betsy,
Your letter inspired the entire editorial staff to go out and weed in the garden and observe insects on our grounds in Mt. Washington, Los Angeles. Many of the species of insects in the east that frequent Queen Anne’s Lace also visit the flowering carrots in our our garden. Pollinating insects love Queen Anne’s Lace and carrots as do predators that prey upon pollinating insects. The staff began to feel guilty that computers were abandoned and emails and comments were left unanswered so we returned to the desk, but we only felt guilty enough to post your letter and wonderful photographs before immediately heading back outside to the sun and activity.
Thanks Daniel! Your entire site today inspired me to go outside and take about 100 pictures of teeny tiny bugs!
I even spotted a spider the size of a pin head that had caught one of those little iridescent flies on a milkweed, a perfectly matched green grasshopper hiding in milkweed blossoms/leaves, and lots of mating beetles!
Our Queen Anne’s Lace hasn’t blossomed yet this year but I always look for the Goldenrod crab spiders and other interesting critters that reside in them on my walks.
Elisabeth
Letter 9 – Immature Ambush Bug
Subject: Ambush bug???
Location: Zuma Canyon, Malibu, California
May 24, 2012 10:39 am
Hi Bugman,
I found this guy on Eriogonum fasciculatum (buckwheat) – I didn’t see him until I moved the flower and he crawled around back to get away from me. I don’t know what he is. The closest thing I can guess is some sort of ambush bug. His coloration is amazing! What is it?
Signature: C. Anderson
June 4, 2012
Hey Bugman!
Still can’t figure out what this is. I am going back out this week to look for him. Any ideas?
Thanks, Crystal
Hi Crystal,
We missed your original email and we returned to our unanswered mail in order to find your location. You are correct. This is an Ambush Bug and it appears to be an immature individual. It is possible it is freshly molted and its colors haven’t darkened yet, or it might have adapted to blend in to the colors of the buckwheat blossom. It might be Phymata pacifica, a species represented on BugGuide from California, however BugGuide has no images of nymphs.
Letter 10 – Ambush Bug eats Bee
Subject: Bee-Eating Bug
Location: Calgary, Alberta, Canada
June 17, 2012 3:12 pm
Hi there,
I had a one time encounter with this bug and have been trying to identify it since 2009. I am not certain if it killed the bee, but it was certainly sucking the juices from it. Any help would be much appreciated! It was found in late summer in Calgary, Alberta, Canada
Signature: Sincerely, Morgan S
Hi Morgan,
This efficient and stealth predator is an Ambush Bug. They frequently wait on blossoms to ambush insects that are attracted to nectar and pollen.
Letter 11 – Ambush Bug Nymph
Subject: Unknown bug in DC
Location: Washington, DC
March 8, 2014 8:54 am
Hi Bugman,
Can you help me with this bug? I found it last summer, in July, in my backyard, in NW DC. It was on my grill. It is really small and looks buggish but seems to have front legs that look like a mantis. Thank you so much for this site and your help.
Stephanie
Signature: Stephanie H.
Dear Stephanie,
This is an immature Ambush Bug, and it does use its raptorial front legs to capture prey much the same way that a Preying Mantis captures its prey. Ambush Bugs were once classified in their own family, but new taxonomy has them identified as a subfamily of the Assassin Bugs.
Letter 12 – Immature Ambush Bug
Subject: bug
Location: Portland Tn.
August 18, 2014 6:50 pm
Would like to know what this bug is and any other info. on it.
Signature: Carol
Dear Carol,
This is an immature Jagged Ambush Bug, and like the winged adult Jagged Ambush Bugs, they are adept hunters that ambush prey, generally by waiting on flowers for pollinating insects. Ambush Bugs ambush prey, grasping them with their raptorial front legs and then using their piercing mouthparts to suck fluids from the bodies of the insects they capture. See BugGuide for a comparison image.
Letter 13 – Ambush Bug eats Honeybee
Subject: Colorado bee eater
Location: Front range colorado
August 7, 2015 6:17 pm
Hi. We were loving this flowering bush and so were the honeybees. Unfortunately tonight we noticed lots of dead bees and lots of these insects- can’t find them online anywhere! They blend right in- look like dried up flowers.
Signature: Bonnie
Dear Bonnie,
When we first saw your subject line, we thought you were submitting images of one of the large, predatory Robber Flies in the genus Mallophora, possibly the Belzebul Bee Eater. Your Food Chain image is just as exciting. This is an Ambush Bug in the genus Phymata, probably a Jagged Ambush Bug.
Thank you, Daniel. Very cool! Feel bad for the bees though 😉
Letter 14 – Immature Ambush Bug
Subject: Interesting green bug!
Geographic location of the bug: 99163
Date: 07/25/2021
Time: 03:34 PM EDT
Your letter to the bugman: Hi there! We’ve been scouring all of our resources trying to identify this little fellow and while he looks a bit like a stink bug, his front legs bend more like a praying mantis and he has a ridge to back that gives him a concave appearance. He’s quite tiny, able to perch on my pinky nail with room to spare.
###-###-#### (Ed. Note: Number redacted for privacy concerns)
How you want your letter signed : Heath B. & Family
Dear Heath B. & Family,
This is an immature insect and immature forms of insects are generally more poorly documented online, which complicates identification attempts. This is an immature Ambush Bug and it uses its raptorial front legs to capture prey the same way the Preying Mantis does.
For the first time ever, your site was just blocked by my virus scanner (AVG). Says there’s an active threat now (I just visited a couple of hours ago with no issue). Just a heads-up!
These are ambush bugs and in southeastern Connecticut, they are either Phymata a. americana or Phymata pennsylvanica. Unfortunately, a species ID is not possible from this photograph.
Just to clarify, they are NOT mating. Mating takes place with the male gripping the side of the female; the depicted behavior, usually called coupling, may improve the odds of taking prey, although I’m not exactly sure.
Additional clarification, there has been some consensus as to the relationships of these insects to other assassin bugs and they are now unequivocally treated as Reduviidae: Phymatinae.
These are ambush bugs and in southeastern Connecticut, they are either Phymata a. americana or Phymata pennsylvanica. Unfortunately, a species ID is not possible from this photograph.
Just to clarify, they are NOT mating. Mating takes place with the male gripping the side of the female; the depicted behavior, usually called coupling, may improve the odds of taking prey, although I’m not exactly sure.
Additional clarification, there has been some consensus as to the relationships of these insects to other assassin bugs and they are now unequivocally treated as Reduviidae: Phymatinae.
This seems to be one of the western subspecies of Phymata americana.
Life’s a bi$ch in the real world, poor pollinators
I’m happy to find this page online! I’m also in the Colorado front range area and was badly stung by a nasty ambush assassin in summer 2014. My finger swelled to the maximum skin-stretch limit, more painful than any hornet’s sting, by 24 hours the skin was actually breaking. It took nearly 6 weeks for the black, coiled stiff threadlike stinger to be exposed at least 3/8″ into my finger, and dead tissue around it sloughed off. I got ID from anyone until an ex-spouse at a NM Lab did some research. Annually I see tons of the bugs anywhere there’s a blossom, killing bees by the millions to rob their pollen. I smash as many as I can but they’re constant “schtoinkers” so I’ll never wipe them out!