Currently viewing the category: "Robber Flies"
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Subject: What is this?
Location: Lynwood Calfornia
August 17, 2014 7:16 pm
Can you help me identify this bug? I found him outside my door step
Signature: Not sure

Robber Fly:  Efferia species

Robber Fly: Efferia species

Dear Not sure,
This is a Robber Fly in the genus
Efferia, and though we went through numerous images on BugGuide, we could not find any that have the exact coloration of your individual.  You can compare your image to this image on BugGuide to see that the general physiology is the same.  According to BugGuide, there are:  “110 spp. in our area,” and “in our area, the vast majority are restricted to sw. US, with some widely western spp. and just two widespread spp.”  According to Eric Eaton, male Robber Flies in the genus Efferia:  “have the bulbous claspers, making them reasonably easy to identify.”  Just as we were about to post, we discovered this image of Efferia antiochi on Sardis & Stamm about the Antioch Dunes National Wildlife Refuge that looks identical to your Robber Fly.  According to the California Department of Fish and Game:  “Known only from Antioch, Fresno, and Scout Island in the San Joaquin River” which would indicate it is not the same species, but is sure looks close.

Robber Fly:  Efferia species

Robber Fly: Efferia species

We would strongly suggest that you contact the Los Angeles County Museum of Natural History as this might be a significant find.

Robber Fly:  Efferia species

Robber Fly: Efferia species

What's That Bug? does not endorse extermination

Subject: Wasp? eating ?
Location: San diego
August 17, 2014 11:06 am
Hello Bugman,
Saw what looks like to be a white and black wasp hanging around the garden today. First time I have seen a wasp like this, it is fairly large, looks like it might be eating a small frog?
Signature: curious

Bee Killer eats Honey Bee

Bee Killer eats Honey Bee

Dear curious,
This predatory Robber Fly is a Bee Killer,
Mallophora fautrix, and it appears to be eating a Honey Bee.

What's That Bug? does not endorse extermination

Subject: Dragonfly eating a bee?
Location: Austin, tx
August 16, 2014 8:49 pm
Hi Bugman!
Found this dragonfly looking insect sucking down a bee in my back yard. Is it a dragonfly? It was definitely drinking the bee. Craziest thing. I have a giant oregano patch bit flower right now and the bees love it. We have a pool so sometimes see dragonflies, but this had some odd features I’d never seen on a dragonfly, like a clear abdomen and a feathery black tuft at the end of his backside. What’s that bug?
Laura
Austin, TX
Signature: Laura

Robber Fly eats Honey Bee

Robber Fly eats Honey Bee

Hi Laura,
You are mistaken in thinking that this is a Dragonfly, though like a Dragonfly, this Robber Fly is an adept predator capable of capturing large prey on the wing.  We believe we have correctly identified your Robber Fly as a member of the genus
Efferia due to its resemblance to many members in the genus, including this unidentified species that is pictured on BugGuide.  According to BugGuide, there are “110 spp. in our area” and “in our area, the vast majority are restricted to sw. US, with some widely western spp. and just two widespread spp..”  We interpret that to mean that many species are very limited in their distribution.  Alas, we haven’t the necessary skills to attempt a species identification.

What's That Bug? does not endorse extermination

Subject: Another Southern Bee Killer?
Location: Coryell County, Texas
August 14, 2014 9:55 am
I saw that you had many robber fly inquiries last week. Here is mine. :-)
You kindly identified a Southern Bee Killer for me several years ago. Is this insect the same? It was hiding in plain sight, holding perfectly still on a young crepe myrtle tree, which is a bee magnet due to its many fragrant clusters of blossoms.
Thank you!
Signature: Ellen

Southern Bee Killer

Southern Bee Killer

Dear Ellen,
Taking a closer look at your previous submission from 2009, we now believe neither is a Southern Bee Killer,
Mallophora orcina, as the individuals pictured on BugGuide all have black-tipped abdomens.  Your individual appears to have a yellow abdomen all the way to the tip, which is why we believe it is a different species in the same genus, Mallophora fautrix.  Compare your images to this individual on BugGuide.  According to BugGuide, it ranges from:  “Texas west to California, southward through Mexico.”  We would really love to get an expert opinion on this identification.

What's That Bug? does not endorse extermination

Subject: Big fly?
Location: corinth, tx
August 12, 2014 6:23 pm
I was . walking the dog and solve this bug eating a cicada.it looked like it was about one and a half to 2 inches long. I have never seen one and I wanted to know what it was.
Signature: Larry L.

Robber Fly eats Cicada

Robber Fly eats Cicada

Dear Larry,
This is some species of Robber Fly in the family Asilidae, and it is not a species we immediately recognize, so we are going to have to research its identity.  It is indeed eating a Cicada.  Robber Flies are highly specialized predators that are very adept at taking large prey on the wing.  Texas and Arizona both have unusual, not commonly seen Robber Flies that are not found elsewhere in the U.S., though the ranges of those species frequently extend into Mexico.  We believe that based on this image from BugGuide, it may be
Microstylum morosum.  According to Beetles in the Bush, this is “North America’s largest robber fly” and “Until recently, Microstylum morosum was considered a Texas-endemic.  However, Beckemeyer and Carlton (2000) documented this species to be much more broadly distributed in the southern Great Plains (from Texas up into Oklahoma and Kansas and west into New Mexico, Arizona, and Colorado), and Warriner (2004) recorded it shortly afterwards in Arkansas.”  We wrote to Eric Eaton to see if he agrees with our identification.

Eric Eaton concurs
I would agree.  Seems to be a pretty distinctive species.
Eric

What's That Bug? does not endorse extermination

Subject: Looks to be a Red-footed Cannibalfly
Location: Franklin, TN (Nashville area)
August 11, 2014 1:32 pm
We’re looking for a confirmation on this being a robber fly. Your site was soo helpful in both researching what we saw out our front door and learning more about the bug in question.
This guy was about 3 cm in length and “snacking” on a wasp.
Our 3 and 5 yr old were fighting for the best position to watch this guy through a window. Question – how bad would a bite from this guy be to a small kid? And, is it okay to hang out around them as they protect our air space?
Signature: Jeff

Red Footed Cannibalfly eats Paper Wasp

Red Footed Cannibalfly eats Paper Wasp

Hi Jeff,
We agree that this is a Red Footed Cannibalfly, and it appears to be eating a Paper Wasp in the genus
Polistes (See BugGuide).  We believe a bite from a Red Footed Cannibalfly would be painful, but otherwise present no lasting effects, however we should qualify that that we believe the chances of being bitten are at about 0% unless a person decided to try to catch a Red Footed Cannibalfly by hand.  They are not aggressive towards humans, and if provoked, they would most likely just fly off.  Handling them is a totally different matter.

What's That Bug? does not endorse extermination