Killer, At Work

Reminder:  You can enlarge any of the photos in this blog by clicking on it.  Click again for a full-screen image.

I went over to Sabino Canyon early this morning and spent several hours wandering around in the dense brush that borders Sabino Creek.  Towards the end of my hike I happened upon a Robber Fly, a/k/a Assassin Fly, resting on a bush.  The fly sat there quietly its mind on things other than me and my camera, and I took its picture.

_92A2737 copy

A Robber Fly is an amazingly well-adapted predator.  Think of it as sort of combining the traits and abilities of Peregrine Falcons and rattlesnakes and you get the picture.  It is a classic ambush predator. It sits quietly on a leaf or a twig, just as this one is doing, waiting for another insect to come flying along.  It has extremely good vision and it can fly with lightning speed.  And, when a potential victim comes within range, it pounces, running it down in the air, and seizing it.  It then injects a venom into the prey that almost instantly paralyzes and then kills it.  The venom serves double duty.  Just like rattlesnake venom it contains digestive enzymes that dissolve the prey’s tissue.  The Robber Fly can drink its victim’s liquified tissues at its leisure.

Look closely at this fly and you’ll see its predatory tools.  Its feet end in talons, not unlike a hawk or falcon’s talons.  Its eyes are huge in proportion to its body.  Its thorax is heavily muscled, designed to rev up its wings for sprinter’s speed.  It has a black, chisel shaped proboscis that it uses to punch through the exoskeletons of its victims so as to be able to inject venom.

I’d only taken a couple of pictures of this fly when it flew off.  I assumed that my camera’s flash had disturbed it and that it was seeking peace and quiet.  But, within five seconds it returned to its perch.  And, to my amazement, I discovered that it had seized a victim.  The Robber Fly had captured a smaller fly and was now dining.

_92A2769 copy

Five seconds’ work.  That’s all it took.  The wonders of evolution never cease to astonish.

Images made with a Canon 5DS-R, 180 f3.5L Macro Lens assisted by Canon 600EX-RT Speedlite, ISO 200, M setting, f16 @ 1/160.

One response to “Killer, At Work”

  1. Liesl Kii says :

    Often you describe your insects as “beautiful” or “darned cute.” Glad you didn’t use those adjectives with this frightening looking creature! Really great photo of the Robber Fly with his prey.

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s