Tag Archives: giant robber fly (Promachus hinei)


Robber flies.  They are killers, predators, mimics and assassins.  But like all flies, they have no crushing mouthparts and therefore have to drink their lunch.  That means for robber flies the proboscis has evolved for piercing and sucking.  One stab and a cocktail of paralytic and digestive enzymes dumps into the prey so it’s easier to handle… and easier to imbibe.

Bee killer (a.k.a. robber fly or asilid fly; Mallophora fautrix) perched on a blade of grass (20081004_13237)

Bee killer (a.k.a. robber fly or asilid fly; Mallophora fautrix).  I find these critters all over the place.  I also see them fall prey to other predators, including other robber flies, but they’re brave insects who seem quite willing to take on anything that flies.  I found this one near the heron lagoon.

Bee-like robbery fly (Laphria macquarti) perched on a bush (2009_04_16_015544)

Bee-like robbery fly (Laphria macquarti).  Even at 400mm, this large monster looked terribly small.  Mind you, I was standing so far away that I could only see a flying thing that I thought was a bumblebee.  Not until I looked at the image at home did I realize what I had seen.

Male giant robber fly (Promachus hinei) perched in a tree (2009_07_17_026746)

Almost a year ago to the day I posted the first photo I’d ever taken of the most common species of giant robber fly in Texas, Promachus hinei.  A month after that I found another one.  Since then, I’ve watched for them and discovered this male perched in the same tree where I saw the first one.

Female giant robber fly (Promachus hinei) perched in a bush (2009_07_18_027117)

And nearby, this female sat quietly in the bushes.  They tussled briefly when they met a few minutes after I took these photos.  Neither won the war and both returned to their respective corners to await other dining opportunities.  Both were gone later in the evening, yet the male found his way back into the tree the very next night.  Did he or something else consume his female counterpart?  Or did she just move on to a less crowded dining table?

Now you don’t

Now you see it…

A male giant robber fly (Promachus hinei) clinging to a half-eaten leaf (20080817_11050)

…now you don’t.

A half-eaten leaf where a male giant robber fly had been just moment before (20080817_11051)

I can’t begin to express how real my walk became Sunday, how personal, how divine.  For now at least that’s one story that shall remain untold.

But for hours before it changed so magically, I trotted about White Rock Lake as though I had no other care save one: to enjoy the morning in surroundings that become discovery at every turn.

Unending rain failed to dissuade me from mindless meandering.  Mud be damned! I thought (although much later when tediously washing my shoes for the umpteenth time, I began to wonder precisely how wise my flippant mindset had been).

Little caught my eye that I hadn’t photographed a thousand times before.  Flowers here, insects there, all manner of birds rushing to and fro.

The partly cloudy skies did little to improve my mood.  As I’ve always said, such days make photography difficult when the clouds create a painfully dynamic situation where a photo is painstakingly setup to perfection only to have a drastic lighting and color change when the push of the button is already mentally committed.

Nevertheless, I wallowed in luxurious nature while trying to ignore the anthropocentric hoopla.

Lush vegetation captivated me as I made my way along the edge of the woodlands along the flanks of Dixon Branch.

Watching crows battle a hawk—at least until the juvenile’s parents showed up—made for better entertainment than any television program or movie.

Bathing my senses in what heavy rains had created offered diversions aplenty…even if a bit usual.

Then behind thicket standing taller than my own head I spied a large insect buzzing about, flitting from spot to spot without landing.  I had no clear view of it of course, and shorts with a tee shirt made infiltrating the brush a daunting and unwise task.

But how I wanted to capture a photograph of the beast.

So I held the camera above my head and swiveled the LCD screen so I could see what I was aiming at.  Then I waited.

Finally landing upon a half-eaten leaf, I zoomed in on the creature and captured the first image, one setup for cloudy weather and snapped just in time for the sun to make an appearance.


I quickly fiddled with the camera to change the options for sunlight, held the soul stealer above my head once again, and tried desperately to find my mark.

There it was right where I left it, on the same leaf in the same position doing the same thing: waiting for breakfast to fly by.

Clouds heavy with moisture provided a modest yet safe opening through which sunshine poured onto the scene, a space large enough to ensure the image would not be ruined by unwelcome changes in illumination.

Although too far away to see it even through brush pushed apart gently, the camera’s zoom brought the massive monster right to my eyes, right in front of my face—relatively speaking, that is, considering I held the camera at arm’s length above my head just to see over the verdant obstacles.

Despite wind that had ruined several images by moving my subjects about randomly at the moment I pressed the button, this target hid in a small opening protected by lush vegetation on all sides, including an impenetrable treeline standing tall against the backdrop of a creek I could no longer see.

I pointed.  I focused.  I centered on the object of my attention.  Then I pulled the trigger.

Just in time to see the second photo.

The doggoned fly dashed into the air in that split-second between mental command and physical obedience.  My mind already had captured a stunning, detailed close-up of it.  My fingers had yet to make that a reality.

And it was gone, off chasing some potential breakfast into the woods and out of sight.

Damn you, you cursed bugger!

Had I not been restrained by my own sense of superior decorum, an unsightly foofaraw would have unfolded right there for the world to see, a tantrum of explosive disappointment and undirected irritation.

But I have my reputation to uphold, one of being better than everyone else, so I waited until I returned home before sending The Kids into rattled annoyance as I blathered ad nauseam about the one that got away.

[photo is of a male giant robber fly (Promachus hinei)]

A few of my favorite things

Because I haven’t the wherewithal to offer more substance than paltry photos, at least at this exact moment…

A female short-winged grasshopper (Dichromorpha elegans) perched on a blade of grass (20080704_09012)

Female short-winged green grasshopper (Dichromorpha viridis)

A female crane fly (subgenus Yamatotipula; Tipula furca) hanging on the side of a tree (20080314_02612)

Female crane fly (subgenus Yamatotipula; Tipula furca)

A giant robber fly (Promachus hinei) clinging to a tree branch (20080711_09237)

Giant robber fly (Promachus hinei)

That last photo is interesting in that it’s the first time I’ve been able to capture an image of the most common species of giant robber fly in the state of Texas.

Although they can inflict a painful bite if mishandled, robber flies pose little threat to people; they do, however, pose a significant threat to other insects.

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.

Their prowess stems from their ability to capture prey in flight, overwhelm them with strength, and deliver a deadly bite filled with acidic juices (something normally targeted at the head).  The robber then drinks its meal in peace.

Most robber flies are considered beneficial to a degree in that they target other pests such as flies, beetles and wasps; others are not so beneficial since they target bees and other beneficial insects.

Giant robbers prefer to travel the middle of the road: they target all prey equally so long as it’s large enough, so they might just as easily destroy a local wasp nest as they would a beehive (the former being good and the latter being not so good).

This one happened to perch on the tree outside my patio one day.  When first I spied it, I thought it a bit of dead leaf or other debris stuck to a branch.

Then it flew after a cicada-killer wasp—a female that easily knocked it aside, I might add, for her size dwarfed the fly and gave her a distinct advantage.  That’s when I realized it was something far more interesting than dried vegetation.