Currently viewing the category: "Robber Flies"
What's That Bug? does not endorse extermination

Subject: Any ideas?
Location: Michigan
July 2, 2017 10:56 am
This bug was on my deck. I live in Michigan. Does anyone know what it is?
Signature: Thank you! Christie Haines

Robber Fly with Prey

Dear Christie,
This is a predatory Robber Fly, probably a member of the genus Promachus, a group whose members are called Giant Robber Flies or Bee Killers according to BugGuide.  It might be
Promachus bastardii based on BugGuide images.

Robber Fly with Prey

What's That Bug? does not endorse extermination

Subject: Unusual flying insect
Location: NC USA
July 2, 2017 10:14 am
This insect photo was taken July 2 at 1pm in Cape Carteret NC. What is it?
Signature: Chris

Red Footed Cannibalfly

Dear Chris,
We are relatively certain that your Robber Fly is a Red Footed Cannibalfly,
Promachus rufipes, based on images posted to BugGuide.  According to BugGuide:  “Preys on large flying insects. Has been reported to attack Ruby-throated Hummingbirds”

What's That Bug? does not endorse extermination

Subject: possible robber fly
Location: Plainsboro NJ
June 9, 2017 4:54 am
The small eyes and short antenna have me thinking this is some sort of bee-mimic. I saw some pictures of robber flies that look a little like this. Can you tell me if this is correct, and maybe narrow it down to a species?
And I suspect they’re having sex; does that sound right?
Found a weekend ago: June 3.
Signature: jpviolette

Mating Bee-Like Robber Flies

Dear John,
Your request arrived on the first day of our holiday and we are currently trying to post some of the best images that arrived while we were out of the office, and that includes your image of mating Robber Flies in the genus
Laphria, the Bee-Like Robber Flies.  Many species in the genus look similar, but we believe your individuals might be Laphria virginica based on images posted to BugGuide where they are described as:  “Easy to confuse with L. flavicollis. The main gestalt things to look for are the hairiness of the black abdomen, very fuzzy in virginica but somewhat glossy in flavicollis. The golden hair on the top of the thorax looks more swept back and finely constructed in flavicollis. And in virginica, the legs have a reddish brown tone to the fuzz in good light. –Herschel Raney, 4.v.2006.”

Thanks – I’m glad I was on the right track. I’ve gotten fairly good at recognizing some of my area’s more distinctive butterflies/dragonflies, but I have a much harder time with these guys (especially mimics).


What's That Bug? does not endorse extermination

Subject: Robber fly?
Location: Lat. 48.372 Long. 123.538
June 24, 2017 9:14 am
Dear Bugman,
Thank you again for this great site!
Here’s a guy my Dad caught in the house yesterday. At first we thought it was a bumble bee, but your site helped me determine that it is likely a fly.
Would you kindly check these photos out, please.
We let it go. It seemed fine after its stay in the glass for inspection! We are still at Lat. 48.372 Long. 123.538, southern Vancouver Island, Metchosin, William Head Road.
Thank you so much for your help!!!!
Signature: Sue Hughes

Bee-Like Robber Fly: Laphria asturina

Dear Sue,
Your images of a Bee-Like Robber Fly in the genus
Laphria are spectacular, and we are especially excited that they nicely reveal the red-tipped abdomen.  Bee-Like Robber Flies are predators and these larger Robber Flies prey upon stinging insects like bees and wasps.  It is believed they mimic their prey, both for protection from other predators who might be off put by the thought of trying to eat a stinging insect, and because they are able to more closely approach prey before alarming a potential meal.  This species seems to have adapted to mimic your locally common red-tailed Tri-Colored Bumble Bee which according to BugGuide should not be called a Red Tailed Bumble Bee because:  “Red-tailed Bumble Bee (not recommended, as it also refers to Bombus lapidarius, a Eurasian species).”  We believe we have correctly identified your Robber Fly as Laphria asturina on BugGuide, but alas, it has no common name.  You might consider posting your images to BugGuide as they only have two examples, and we do believe your images are better for identification purposes.  We also located an image of a living individual and its meal on PICSSR (warning:  adult ad content on this link).

Bee-Like Robber Fly

Hi Daniel,
Thank you very much for help with our latest bug adventure!
I will send the images to BugGuide on your say-so, if I can figure out how to do it.
You  have made our day!!
Cheers, Sue

Bee-Like Robber Fly

What's That Bug? does not endorse extermination

Subject: Strange Wasp?
Location: Monterrey, Nuevo Leon, Mexico
June 25, 2017 6:03 am
Hi Bugman!
Earlier today I found this big wasp that got in my window somehow, and I’d like some help identifying it since I couldn’t figure out what type of wasp it was, or if it’s even a wasp! I’ve never seen a bug with an abdomen shaped like that.
Signature: Sebastian

Robber Fly

Dear Sebastian,
This is not a wasp.  It is a predatory Robber Fly in the family Asilidae.  It might be a Bee Killer in the genus
Promachus which is represented on BugGuide.

What's That Bug? does not endorse extermination

Subject: Wasp?
Location: Southwestern Ontario, Canada
June 24, 2017 9:46 am
I’ve photographed a few of these small (1 cm) wasps(?) with a blue patch between the eyes. I’m uploading a shot of one eating an Orius insidiosus (I think).
Signature: Jim Elve

Robber Fly eats Insidious Flower Bug

Dear Jim,
Your image is gorgeous and quite detailed.  This is not a Wasp.  It is a Robber Fly (see BugGuide) in the family Asilidae, and we generally only attempt to identify large Robber Flies to the species level as so many smaller species look quite similar.  We agree that the prey is an Insidious Flower Bug based on BugGuide where it states:  “important predator of phytophagous mites and mite eggs, insect eggs, soft-bodied insects”.

Thank you, Daniel. Your prompt reply is very much appreciated.
FYI, I have quite a few more bug photos on my website if you’re interested. I have probably misidentified many. I’ll be correcting a couple of shots of the robber fly. Thanks, again!
Best regards,
Jim Elve
What's That Bug? does not endorse extermination