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

Subject: What is this creature?
Location: Huntsville Alabama, outskirts of city
July 24, 2016 5:46 pm
Hi
I live in Huntsville Alabama and saw these insects on the railing of my deck. Never seen this creature before. Any id assistance would be appreciated! It’s been close to 100 degrees here, has now cooled off for the evening to about 80-85.
Signature: Carolyn Sanders

Mating Red Footed Cannibalflies

Mating Red Footed Cannibalflies

Dear Carolyn,
We have a few images in our archive of mating Red Footed Cannibalflies,
Promachus rufipes, a large impressive species of predatory Robber Flies, but nothing comes close to your amazing images.  It looks like you were several inches away.  Though they are not aggressive toward humans, Red Footed Cannibalflies look quite frightening, so we applaud your courage in securing these awesome images.  We are also quite impressed the amorous pair did not fly away when you got close.  Though not aggressive toward humans, Red Footed Cannibalflies are able to take down very large prey, including stinging wasps and bees, on the wing, and we have read on Hilton Pond Center that a large Robber Fly can even prey upon a hummingbird.  We would also caution against trying to handle a living Red Footed Cannibalfly with bare hands as that would most likely result in a painful bite.

Mating Red Footed Cannibalflies

Mating Red Footed Cannibalflies

What's That Bug? does not endorse extermination

Subject: Help what’s this bug
Location: Sherman, tx
July 18, 2016 4:38 pm
This creepy critter landed on my car, I live in Sherman Texas.
Signature: Kristi

Hanging Thief

Hanging Thief

Dear Kristi,
This formidable predator is a Robber Fly in the genus
Diogmites, a group known collectively as Hanging Thieves.

What's That Bug? does not endorse extermination

Subject: What killed this wasp!?
Location: Cincinnati
July 18, 2016 3:24 pm
The other day my girlfriend saw this larger mosquito looking thing on her chair. And then today we saw it take down a full grown wasp! We want to know if we have been brought a savior, or will it kill my family in my sleep?
Signature: Billy Yeager

Hanging Thief eats Paper Wasp

Hanging Thief eats Wasp

Dear Billy,
The predator in your image is a Hanging Thief, a Robber Fly in the genus
Diogmites, and it is easy to see where they got their common name by looking at your image.  Thief is a synonym for the family name Robber and the members of the genus Diogmites frequently feed while hanging from a single front leg.  Large Robber Flies are impressive predators that hunt on the wing, and BugGuide describes the diet of the Hanging Thieves as eating “insects (often larger than themselves), mostly aculeate Hymenoptera, but also Odonata and Diptera (incl. members of the same species).”  The stinging insects in the order Hanging Thieves feed upon include wasps as in your image and bees. 

What's That Bug? does not endorse extermination

Subject: Big yellow fly
Location: Western NC
July 17, 2016 4:56 pm
Greetings to you: I studied some entomology in college and stay fascinated with all 6 and 8 legged creatures. Today this fly was menacing like bee flies are not. It was about 4cm in length. Any idea? A robber fly maybe?
Signature: Buzz in NC

No need to reply, I know now it’s a robber fly.
Thanks!

Robber Fly

Robber Fly

Dear Buzz in NC,
We know you wrote we didn’t need to reply, but we thought you might be curious if we were able to take the identification further than the Robber Fly family.  We are pretty certain this is one of the Bee-Like Robber Flies in the genus
Laphria, and it looks like a pretty good match to the images of Laphria apila on BugGuide, but those images all represent a single individual from Florida.  Your individual appears to have more yellow on the abdomen, but that could represent variation within the species, or it might be a different species.  Your individual looks like this BugGuide image that includes this comment from Ben Coulter:  “The bald thorax with long fringe of hairs on the margin reminds me of apila. I hate to suggest it without good reason, but perhaps this is one of those oft-invoked undescribed species.”  Here is another BugGuide image that is unidentified, though there is some speculation it might be Laphria apila.

What's That Bug? does not endorse extermination

Subject: Bug from Costa Rica
Location: Monteverde, Costa Rica
July 17, 2016 6:36 pm
Hi Bugman,
I’m a biologist and photographer currently on vacation in Costa Rica, where I’m doing an ecologically-minded tour through the country to see wildlife. I have been having an absolutely amazing time and there are so many beautiful insects to be seen and identified. As a long time follower and fan of What’s That Bug, I thought I would submit one and see if you had any idea what it is (perhaps family/order/genus if not species). I have a lot of photos of bugs that have yet to be ID’d but I don’t know where to start with this one in particular. The bug was sighted in the Monteverde region and the photo was taken with a Canon 100mm f/2.8 macro lens. Thank you so much for your time and please keep up the excellent work!
PS: If you have any interest in seeing the other bug photos I have taken so far, I would be happy to share! I got a great shot of a bullet ant, among others.
Signature: Casey

Robber Fly

Robber Fly

Dear Casey,
Thanks for the compliment.  By all means submit more images, but please continue to use our standard form and please confine your submissions to one species per form unless there is a good reason to submit multiple species together.  This Fly in the order Diptera is a Robber Fly in the family Asilidae, but when we did a search for Asilidae Costa Rica, we did not find any matching images.  The closest we could find is this similar looking female Robber Fly from the UK.  Your individual appears to be a male judging by the claspers as the tip of his abdomen.  We suspect that there is much Robber Fly diversity in Costa Rica and we also suspect they are not as well documented as larger, flashier insects like butterflies, moths, beetles and katydids.  Here is a Costa Rican Robber Fly on Quaoar Power Zoo that is definitely NOT your species.  Robber Flies are adept predators that often take prey on the wing.

What's That Bug? does not endorse extermination

Subject: Um, super cool
Location: Las Vegas, nv
July 14, 2016 1:34 pm
What the heck is this guy? He’s just chilling on my patio. I got really close to him, he’s fearless but non aggressive.
Signature: Las Vegas

Robber Fly:  Efferia albibarbis

Robber Fly: Efferia albibarbis

We believe we have correctly identified your Robber Fly as a male Efferia albibarbis based on images posted to BugGuide.

What's That Bug? does not endorse extermination