If you were an insect or even a hummingbird, you would definitely not want to encounter this large insect with the macabre moniker of Red-footed Cannibalfly (Promachus rufipes), also known as the Bee Panther.
This insect is considered to be a giant robber fly. Robber flies in general are predators that wait for their prey to fly by and then attack it. Wikipedia describes the attack in this way, “The fly attacks its prey by stabbing it with its short, strong proboscis injecting the victim with saliva containing neurotoxic and proteolytic enzymes which very rapidly paralyze the victim and soon digest the insides; the fly then sucks the liquefied material through the proboscis.”
It’s hard to believe that a fly could actually take down a hummingbird, but bugguide, which I have found to be a good reference for insects, notes that there have been reports of a Red-footed Cannibalfly attacking a Ruby-throated Hummingbird.
When I first saw this insect fly by, I thought it was some strange kind of hairy dragonfly, but the more that I looked at it, the more I realized that it was not a dragonfly—the eyes and wings were all wrong. I have spotted several of these flies already, but so far have not seen any with captured prey.
I came across a wonderful commentary on these insects in a blog called Ohio Birds and Biodiversity that sums up my feelings about them—”Be thankful these insects aren’t the size of Sandhill Cranes.”
© Michael Q. Powell. All rights reserved
Mike Powell 
WOW! Cool insect, although I wouldn’t want to get close to it. Interesting information too.
As stunning as the photos are the information this time is actually better. Your blog is an amazing tutorial.
Suddenly I am very thankful. What vicious creatures roam this planet!
WOW, what a scary insect that is.. I wouldn’t want to meet one of those.
Great photos as always Mike, but what a fantastic name this creature has! 😀
Thanks, At times I wish I had a job as the guy who makes up names for insects.
Wicked cool bug and superb pic. I think I have a pic of one from Pennsylvania….:-)
Thanks, Ed. When I took the shots, I had no idea what it was, but could tell it was a cool insect.
Whoa! We have robber flies up here at the lake too, but this is the first I’ve learned of this branch of the family. Thanks for taking the time to present the results of your experience and your research.
Previously I had seen only a smaller version of a robber fly and was not at all sure what this insect was. It was only when I started poking about that I learned that robber flies come in lots of sizes and varieties. Some folks may learn a lot about their subjects before they photograph them. I usually learn about the subjects after I have taken their photo–shoot first and ask questions later.
That’s my usual approach as well, though I don’t think I’ve ever heard the phrase used in connection with photography. How appropriate–love it!
Have these at my job, a winery. Wasps love to nest among the tanks. Have twice spotted the fly actually carrying the dead wasp around. Thought it was dragon flys mating but closer look revealed the fly.
I can certainly understand the confusion. I recall when I thought I was seeing two dragonflies mating and it was instead a dragonfly that had captured a bee.
I have seen this insect take down a Horse Fly (family Tabanidae). One summer, while working as a lifeguard, our waterpark was infested with Horse Flies. Really painful bites. And strong, durable “little” bugger, hit them out of the air and they get back up and try and bite you again. Well, I saw what I thought was a Horse Fly land near-by and I was about to smack it. Just as I’m about to swing, it darts off snags a real Horse Fly out of the air then turns around landing right back where it was before. It was a Red-footed Cannibalfly. I quickly spread the word about this to my guards and that this particular insect was not to be harmed. I Love this guy!
That’s a really cool story. I have read that these flies are fierce hunters, but have never seen one in action. The biting horse flies are the worst–I am in favor of any insect that will get rid of them.
[…] Red-footed Cannibalfly (Promachus rufipes). I first spotted one last summer and noted in a posting that these insects, sometimes referred to as Bee Panthers, are reported to be capable of taking […]
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had seen these all my life but never knew they ate wasps until i saw it twice do it on my bird feeder– loves red wasps,thanks for the info Mike,very interesting!
Thanks. I am fascinated by the red-footed cannibalflies and by all kinds of other creatures. Initially I learned more about them in trying to identify the subjects that I had shot. I discovered all kinds of fascinating information on-line and enjoy sharing it.
[…] others with 1327 views, including 244 within the last thirty days. The posting was simply called Red-Footed Cannibalfly and it has remained remarkably popular over an extended period of time. In fact, if you do a […]
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I love the damselfly photo. They remind me of faeries. That looks like a killer fly. 😉
Thanks, Cheryl. There is definitely something magical about dragonflies and damselflies. As for Red-footed Cannibalflies–they sure so look like the ruthless killers that they are.
I can’t that I find any regular fly lovely and ever since the movie The Fly, the old version even, I can hardly bear to look at them too closely. Except for the tiny irridescent ones. They are like glitter in the garden. Lol
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Yep. Something like this the size of any large bird would be one scary demon. The fact that it is called a cannibal fly makes me think that it eats its own species since all robber flies eat insects…and the occasional hummingbird.
With all the gorgeous dragonflies you have posted I am surprised this has received the most hits despite its, for some of us, beauty. Of course longevity plays a part and I bet the name attracts a lot of curious onlookers as well. And yes, shoot first and ask questions later. While reading Mr. or Ms. Google the subject will vamoose. 🙂
My most popular post ever was actually a piece I did on the rescue of an injured bald eagle in 2014. (https://michaelqpowell.com/2014/11/04/rescue-of-an-injured-bald-eagle/). Several local media outlets picked up the story and included links to the blog. I had 3200 hits on that post in November 2014 and the current total is “only” 3469, suggesting it does not garner as much attention from Google search results as the red-footed cannibalfly. The red-footed cannibalfly is far from being my best photography, but it continues to get views. It really is a mystery to me why certain postings get views long after they are published. In 2021, for example, my most popular post with 586 views is a posting I did in 2019 called Groundhog in a tree (https://michaelqpowell.com/2019/04/11/groundhog-in-a-tree/). In 2019 when it was published, it had a total of 55 views. The resurgence in views makes no sense at all to me. 🙂
I’ve never kept track of hits per se, I do see the bar graph but don’t check back later. I consider myself lucky to get 32 hits much less 3200. 🙂
I sort of consider it a success if I get 50 views of one of my daily posts and a daily total of 100 views. It’s pretty rare for one of my posts to accumulate 100 views–only 3 of the 39 posts I published this month hit that mark. I accept that there is a randomness to the system and I never know in advance which posts will be “popular” and which ones won’t. I share images and stories that I find interesting and am happy when others enjoy them too.
At some point most of us who may have had aspirations of some resemblance of financial success with our photography recognize that it isn’t going to happen and realize the best course, as it always has been, is to photograph for ourselves. That others appreciate our work is a bonus. That has become my outlook and every once in a while someone wants to purchase an image, either for their wall or a magazine article. Frog Friday has become a hit but now I feel pressure when I go out that I should make frog images so as not to disappoint.Fortunately I like frogs. 🙂
I’m with you, Steve. I is better for me to be an amateur, take photos because I love doing so rather than be motivated by money. It is really, really tough, it seems, for someone to make a living as a photographer. As for frogs, I love them and you have been capturing some really beauties. 🙂
[…] this insect with the macabre moniker. In August 2013 I did a posting with the fairly basic title of Red-footed Cannibalfly. The posting was a modest success and had 61 views in 2013. Since that time, though, the posting […]