Currently viewing the category: "Robber Flies"
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Subject: Bug ID
Location: Central Florida
November 9, 2016 12:44 am
I found this bug in Orlando, Florida in the fall. It seemed to be hairy and was mostly black with small touches of yellow on its body. It had large wings.
Signature: Meg

Southern Bee Killer

Southern Bee Killer

Dear Meg,
We feel confident, because of its markings, that your Robber Fly is a Southern Bee Killer,
Mallophora orcina.  This large predator takes large prey, including bees and wasps, by catching them on the wing.

What's That Bug? does not endorse extermination

Subject: Is this a wasp?
Location: Canterbury, Sydney, Australia
November 3, 2016 12:58 am
Hello! This “little” guy is currently in our kitchen, we will try to remove him. I’m wondering what this is, my first guess would be wasp but im not sure. I couldn’t get a good view from the side so I’m not sure what the midsection looks like. He’s about an inch from the top of the first leg to the bottom of the stinger (?) We are in the third month of spring, its been warm and windy. We live in the suburbs though plenty of flowers and trees around.
Cheers!
Signature: Spires

Robber Fly

Robber Fly

Dear Spires,
This is a Robber Fly, and that is an exceptionally long ovipositor (see BugGuide) and not a stinger.  Large Robber Flies might bite if carelessly handled, but though they are predators, they are not aggressive toward humans.  We could not find a visual match on the Brisbane Insect site.

What's That Bug? does not endorse extermination

Subject: Northwest Montana Bug?
Location: Northwest, Montana
October 16, 2016 8:35 pm
This bug was on the wall at a store, in Northwest Montana, USA. It also seemed somewhat aggressive.
Signature: Danielle Peirce

Robber Fly, possibly genus Stenopogon

Robber Fly, possibly genus Stenopogon

Dear Danielle,
This is a predatory Robber Fly in the family Asilidae, and it greatly resembles this member of the subfamily Stenopogininae that is pictured on BugGuide.  In our opinion, it seems to resemble members of the genus
Stenopogon that are pictured on BugGuide where it states:  “diversity about equally divided between Eurasia and N. America (w. Canada to Costa Rica); in our area, mostly sw. US (the wast majority restricted to CA), with 3 spp. more widely western, ranging into ND-IA-MO-AR.”  The only species that BugGuide reports from Montana is Stenopogon inquinatus, and your individual might be a member of that species when compared to this BugGuide image.  Large Robber Flies are able to take down large winged prey, including Dragonflies, Bees and Wasps, but they are not aggressive towards humans.  With that said, carelessly handling a large Robber Fly, if a person is even able to capture one, might result in a painful bite.  Random Natural Acts has some very nice images of large Robber Flies.

What's That Bug? does not endorse extermination

Subject: Flying “Bee” that eats flies…
Location: Pacific Northwest
October 4, 2016 5:34 am
The Pacific Northwest always seems to come up with tales of strange creatures…BigFoot, D.B Cooper, the Puget Sound Monster…and now a mysterious flying insect that feeds on flies.
I’ve witnessed this assassin do its work usually during the Summer months (actually, I’ve only seen it during the Summer months) and is most active during daylight hours.
It resembles a black and white bumble bee (the white almost exactly replacing the yellow areas of the common bee). Its predatory method is to hover around wherever there are flies, and amazingly will swoop down on top of a fly before the fly knows what hit it. After a few seconds, predator and prey fly off into the sunset.
But the assault is even more interesting. I bore witness to the process while these mysterious fly-eaters did their work on the sunny-side of my tent while camping in Oregon. The flies were congregating on the Western side of the tent, around 1pm, and there were a lot of them. Big and small (so I don’t know how many species there were). Out of no where a flight of these assasin bugs began hovering over the flies. They would swoop in and lans on top of their target. Then, as they allowed me close enough to witness, they spin the fly over and over as their pincers clip off their victim’s wings and legs before flying off with only the torso remaining. It was rather cool to see…there were many of the assassins, and over the course of an hour I witnessed a thousand legs and wing fall along the side of the tent.
I’ve seen these bugs from the Columbia River Gorge, to metropolitan Portland, OR, to the Oregon/Washington Coast.
(Apologies for no pictures, and it isn’t for lack of trying. I have tried many times, but those little buggers are pretty darn quick…and small.)
Signature: Please Bug Me

Bee Killer Eats Wasp

Bee Killer Eats Wasp (from our archives)

Though you did not provide an image, we found your letter highly entertaining, and we believe you observed one of the predatory Robber Flies that mimics a bee.  There is one species known as a Bee Killer in California, Mallophora fautrix, but we don’t know if it is also found in Oregon.  Another possibility is a Bee-Like Robber Fly, Laphria astur, that is found in Oregon and is pictured on BugGuide.  There are also many other possible species, but without an image, we do not want to speculate.

What's That Bug? does not endorse extermination

Subject: Flying insect
Location: Canarian island
September 17, 2016 4:05 am
I foundation this insect on my Windows in Gran Canaria
Thatcher insect is +/- 4cm long.
It is dangerous?
Signature: Insect

Robber Fly

Robber Fly

This is a Robber Fly, and here is a very similar looking individual posted to Getty Images.  While a large Robber Fly might bite a person if it is carelessly handled, they are not aggressive towards humans, but they are predators that frequently hunt on the wing.  Based on this Alamy image, your individual might be Promachus latitarsatus.  The species is also pictured on Biodiversidad Virtual, and an image on Diptera Info shows a large Robber Fly eating a Dragonfly.

What's That Bug? does not endorse extermination

Subject: Giant fly/bee thing?
Location: Maryland
September 10, 2016 5:28 am
Today on my bus route I had an unexpected passenger. I live in Maryland and we had a heat index of 108 at the time. He/she was a very loud flyer and looks like a cross between a bee and a fly and did not seem to want to go outside. Please help me identify him/her.
Signature: Notsocrazy

Red Footed Cannibalfly

Red Footed Cannibalfly

Dear Notsocrazy,
This predatory Robber Fly is commonly called a Red Footed Cannibalfly.

What's That Bug? does not endorse extermination