Category Archives: Prairie Photography

My Wife Finds A Basement Visitor

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One of the best parts of a happy marriage is being periodically reminded that you’ve found just the right partner.  My latest example of that came this weekend, when my wife came up from our basement with a jar containing a beautiful inch-and-a-half-long house centipede.  Kim had been doing laundry and spotted it on the floor.  Instead of stomping on it, she trapped it and delivered it to her crazy photographer husband.  I sure do love that woman.

House centipede (Scutigera coleoptrata)

Since house centipedes are fleet of foot (feet?) and can have a pretty painful bite, I had to come up with a creative way to photograph this one.  I needed to get close to the centipede without it getting away (and/or scurrying up my arm) but also didn’t want any glass jar walls or other obstacles between my camera and my subject.  My eventual solution was to put the centipede in a shallow but slippery white porcelain serving bowl from our kitchen.  The little critter couldn’t quite climb the walls, but I could still point my camera right in its face, especially when it stopped and faced upward on the side of the bowl.  I placed the bowl on my dining room floor in a beam of late afternoon sunlight from the window and clicked away with my camera.  (I’ll add the white serving bowl idea to my other homemade photo studio options, which include an old wheelbarrow.)

House centipedes are native to the Mediterranean region of the earth, but have spread across much of the globe, often cohabitating with people.  They can live outside, especially in moist places under leaf litter, rocks, or other cover, but don’t do well with cold winters.  In places where temperatures dip below their comfort level, house centipedes tend to make their way into warm basements like ours.

As predators, house centipedes have a wide range of prey, including crickets, silverfish, earwigs, and spiders.  They have modified front legs called “forcipules” through which they inject prey with venom.  Because the venom comes from forcipules instead of actual mandibles, it is considered a sting, rather than a bite when the skin is pierced and venom injected.  I bet most prey don’t care much about the distinction.

This cropped image shows the sharp brown-tipped forcipules used to inject venom into prey.  They are right behind the spiky maxillae, and while they look like fangs, or mandibles, the forcipules are technically modified legs.

House centipedes have 15 pairs of legs at maturity, but start out with only 4 pairs when they hatch from eggs.  As they grow and mature, they add about two sets of legs every time they molt.  The rear-most legs of females look like giant antennae, growing much longer than their other pairs.  While I was playing with the my photo subject (before I figured out the serving bowl strategy), those long rear legs accidentally got caught between the rim of a jar and the floor, and they popped off.  They twitched for a minute or two afterward, which I assume could distract a predator and give the speedy centipede time to escape.  The twitching legs distracted me too, but I still managed to keep the jar firmly over the centipede.

House centipedes are nothing to worry about, probably help keep other basement-dwelling insects under control, and will usually try to stay out of your way.  Since my serving-bowl-photo-studio design kept the centipede at a safe distance from me, I didn’t have a chance to test the severity of its bite/sting, but a little research makes it sound like it feels similar to a bee sting.  I’m happy to trust the internet on that, I think.

Face to face on the inclined edge of a white serving bowl…

Photo of the Week – December 1, 2017

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Back in July, my daughter tagged along with me on a trip to the Niobrara Valley Preserve.  Because she’s in college now, and I don’t see her all that often, it was particularly gratifying to have a few days of concentrated time together.  On the last morning of our trip, we decided to hike the Preserve’s public trail through some hills overlooking the Niobrara River and its valley.

The peacefulness of this scene belies the violence that had taken place only a few moments before…

Not long after we started walking, I heard a cicada burst out of the grass in front of us and loudly rattle off into the prairie.  It was a sound we’d heard many times over the previous days, but this time, instead of fading gradually away, the sound stopped suddenly, only a second or so after it started.   A couple steps later, my brain finally identified the anomaly and I turned around and walked in the direction the cicada had flown.  I found it where it had landed, and quickly saw why its flight had been cut short.  The cicada was lying on the ground, making short buzzing noises, and there was a big robber fly sitting right on top of it.  The scene was particularly impressive given the size of the cicada (about the size of my thumb) compared to the much smaller fly.

Despite being significantly smaller than the massive cicada, the robber fly brought it down pretty quickly , and seemed to know just where to insert its proboscis between the chinks in the cicada’s armor.

Robber flies are common in prairies, and we’d been seeing quite a few hanging around during the previous weeks.  I knew they were voracious predators, but had never seen one take down another animal so much bigger than itself.  Only a year ago, I got to watch one intercept and kill a tiger beetle that was trying to fly away from me.  Watching that robber fly come out of nowhere to knock a beetle out of the air was impressive, but at least in that case the predator was a lot bigger than its prey.

I photographed this robber fly just a week or so before the cicada attack.

Since I didn’t actually see this particular attack, I can only assume the robber fly followed the typical robber fly script.  It was probably perched nearby, scanning the skies for prey, and as the cicada lifted off, the robber fly launched itself like a guided missile and rammed into the cicada, knocking it to the ground.  Then, it must have very quickly employed its hypotharynx (modified mouthparts) to inject a toxin into the cicada.  That toxin rapidly immobilized, and eventually liquefied the cicada’s insides.  By the time I arrived on the scene, the cicada was already close to death, and certainly wasn’t going anywhere.  Anna and I didn’t want to disturb the robber fly’s meal, so we walked on, leaving the fly to suck the cicada shell dry – a well-earned meal.