Robber flies deliver a painful bite, so be careful with them. Robber flies are a diverse group of predatory flies that typically perch in an open area, swiveling their heads to look around, then flitting out to chase insect prey. It waits on a perch near flowers where it can see bees from above. Flies have two wings, while wasps have four. But true flies always have the same characteristics: only one pair of wings (bees and wasps have two pairs); the second pair of “wings” on true flies are reduced to tiny knobby structures called halteres (which function like gyroscopes, assisting flight). They don’t “go after” humans, but if you mishandle them, they might bite. Sand fly bites are very painful. Once prey is spotted, it launches and grabs the insect in midair with spiny legs, then lands and uses its piercing mouthparts to drink the prey’s body fluids. One noteworthy robber fly is the hanging thief which will feed on captured prey while hanging upside down from one leg. Both are visual predators. Like other robberflies they are hunters, catching beetles, grasshoppers, wasps, and other flies, including each other! There are differences, of course, if one looks close. The long, cylindrical abdomen is cream colored with thick, black cross-bands. However, unlike bees and wasps, Robber Flies do not sting , and the " stinger " on this Robber Fly is actually a harmless ovipositor that she uses for laying eggs. Robber flies’ audacity is legendary; on the Internet, one can find many stories of robber flies attacking bees, wasps, large grasshoppers, even hummingbirds. Robber flies are well equipped to catch flying insects and can actually snatch a snack right out of the air. Fly bites can cause symptoms such as itching, redness, and swelling. Flies may be fun for cats to catch, but they can also be a problem. Scared the CRAP outta me. Both adults and larvae are predators on other insects. Predators of the Robber Fly include other Robber Flies … Find local MDC conservation agents, consultants, education specialists, and regional offices. When it's flying around, it buzzes noisily and is intimidating. The robber fly is a predator of almost all flying insects. They don’t “go after” humans, but if you mishandle them, they might bite. Nonetheless, it makes stinging motions, brandishing genitalia at the tip of its abdomen as if it had a stinger. Robber flies also have a distinctive hollow space between their 2 large compound eyes. Find out all about horse fly bites, black fly bites, deer fly bites, and more. This is one of more than 20 similar-looking species of robber flies in genus Promachus (PROM-uh-kuss), all called giant robber flies or bee killers, that occur in North America north of Mexico. Physically similar to drain flies, this species preys on mammals and reptiles. A few species of the genus Promachus are serious pests of apiaries because they feed on bees. A few species of the genus Promachus are serious pests of apiaries because they feed on bees. Some robber flies in the genus Laphria look almost exactly like bumble bees, complete with yellow fuzzy patches on their rather pudgy bodies. Between the two large compound eyes, the head is depressed, with three tiny eyes (ocelli) in that little valley. Larval and adult robber flies are predators of other insects, and are famous for their ability to capture prey in the air. Although they don't attack or bother humans, Robber Flies can bite quite painfully, so do not capture or pick up these flies with your bare hands. A gardener’s friend, indeed! Robber fly, (family Asilidae), any of about 6,750 species of predatory insects, worldwide in distribution, in the fly order, Diptera. Robber flies are conspicuous denizens of the desert southwest, but are common nearly everywhere. I got some nice shots - they get better towards the end, so fast-forward if you get bored! Common Name: Robber fly Scientific Name: Varies Order: Diptera Description: Adult stages are medium to large (3/8 to 1-1/8 inch) flies often observed on stems of plants, on the ground or flying low. Robber flies are aerial predators of a variety of insects. For that reason, Robber Flies are efficient predators, and they have a big appetite for bugs. Body length (not including appendages): most are ½ to ¾ inch; varies with species; some reach 1¼ inches. The most commonly seen robber flies are dark in color, but some common types are orange. Robber flies live in urban areas, forests and woodlands. If one lands on you, don’t slap it — instead, brush it lightly away. A giant robber fly particularly likes to eat bees. They certainly bear little resemblance to house flies. This nice big Giant Blue Robber Fly seemed pretty angry at being trapped inside the window, so I was a tad wary about catching it at first as I didn't know if it would try to bite me or not - I was blissfully unaware of it at the time, but they have a ferocious reputation for being quite aggressive! Family Asilidae – Robber Flies Live adult female robber flies photographed in the wild at Winfield, Illinois, USA. Some cats are susceptible to fly bites on their ears, especially cats that live outdoors. Bee flies are stout-bodied flying insects said to resemble bees, but there are syrphid flies and robber flies that do a much better job. True flies with no stinger and only one pair of wings, robbers are predators—and giant robbers will attack any insect that flies, including wasps, bees, grasshoppers and dragonflies. We protect and manage the fish, forest, and wildlife of the state. Flies cannot sting, and only certain flies bite (i.e. Yellow Flies The one pictured is called a bee-mimic robber fly… While they rarely attack humans, they can inflict quite a nasty bite if provoked causing pain, swelling and redness at the bite site. Although they do not sting, Robber Flies do bite and their saliva contains neurotoxins to quickly immobilize prey and proteolytic enzymes to dissolve its internal organs so that they can later be easily sucked out. The grublike larvae, as they move around in decaying organic materials, eat the eggs and larvae of other insects. I literally screamed. Facts about robber flies. The typical foraging strategy of robber flies is similar to that of birds in the flycatcher group: They perch in exposed locations, then flit out to snatch prey, often returning to the same perch. Larvae are grublike and live in or on soil, among decaying materials, or in rotting wood. 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