The Boneheaded Ecologist and the Zombie Fly

Last summer, while working on my square meter photography project, I made a lot of discoveries, including quite a few species I’d never seen before. Only one made me briefly question my understanding of life and death.

I was peering into my little square meter plot one morning in August when I spotted something light-colored sitting motionless on top of a dewy leaf of grass. It was small enough that I had to train my macro lens on it to get a better look. What I saw through the lens appeared to be the exoskeleton of a small fly. It was pale and appeared to be just an empty shell.

Now, tt’s been long enough ago that I don’t remember exactly WHY I thought it might be the exoskeleton of a fly; it seems pretty far fetched in hindsight. There are two ways I could have been right. First, the “fly” could have been dead. Maybe it was killed and eaten by a spider or assassin bug, both of which feed by liquefying and then sucking the insides out of their prey. I might have been looking at a discarded husk of something a creature like that had eaten. However, the fact that the insect was perched upright on a piece of grass makes that seem pretty unlikely.

The second possibility is that the “fly” had molted out of its previous exoskeleton after outgrowing it. This happens with the nymphs of various species that go through incomplete metamorphosis. However, flies don’t go through incomplete metamorphosis – they transform from larva to adult via a pupal stage. Because of that, there’s no way I could have been looking at the shed skin of a fly. I’m such a chucklehead.

Nevertheless, at that particular moment, my brain was telling me that I was looking through a macro lens at a fly’s exoskeleton. Even if it wasn’t an empty fly, it sure looked like the dried and hollowed out body of SOMETHING. Picture my shocked face, then, when that dead empty shell started to slowly walk up the leaf…

Now, I want you to study the above photo. That’s a dead creature, right? Of course it is. Except that it wasn’t. I’m not the brightest bulb, but even I know that zombie flies, or any kind of zombie insect, aren’t a real thing. (Don’t you dare steal my movie idea, though – it’s MINE!) Clearly, I was looking at some kind of living creature. I just couldn’t imagine what it might be.

Later, I discovered that my “zombie fly” was really a derbid plant hopper. According to bugguide.com, “Derbids generally can be recognized by having the row of spines on the second hind tarsal segment and having the apical segment of the beak short.” Oh. Well, now I feel silly… I completely missed that row of spines on the second hind tarsal segment, and I didn’t even think to look for the apical segment of the beak!

Look at the gorgeous blue and red coloring on the wings of this derbid planthopper. This photograph is from September, but is the same species as the one I photographed in August. I found another in early October, and all three were within my square meter plot. I’ve not yet seen one elsewhere (but I’m sure they exist).

Derbid planthoppers are a very diverse group of insects with almost 1,700 species found around the world. According to a couple online sources, derbid nymphs feed on fungi. Adults feed on plants, and at least some are host-specific, meaning that they feed only on a single plant species or group of species. I would love to know if the derbid I photographed was a specialist feeder on one of the plants in my little plot. I would also love to know if the derbids I found in the plot in September and October were actually the same individual as the one from August. It seems unlikely – but probably more likely than a zombie fly.

Photo of the Week – February 1, 2019

It’s till pretty drab and brown outside, so today’s photos are again selected from last summer’s shots. I’m sure I’m not the only one who is glad to look at some color.

We missed out on most of the polar vortex here in Aurora; we only dropped as low as -5 degrees one night, and we’re back up close to 50 degrees today. The misplaced jokes I’ve heard (“heh heh, global warming, am I right?”) reminded me that I’d written a post several years ago about how global warming does, in fact, influence longer and colder temperatures at times during the winter. I looked up the post and was dismayed to see it was almost SIX YEARS OLD. And we’re still arguing (and joking) instead of acting.

Moving on, though, here is some color from last August. I photographed bees and a few other insects on tall thistle (Cirsium altissimum) several different times during that month. (Which reminds me of another previous post, this one on native thistles and their importance to pollinators). Here are some highlights from those August thistle photos.

A crab spider waits for the next pollinator to stop by…
A skipper butterfly on tall thistle at our family prairie.
I think this might be a fruit fly (Tephrellia?) that lays eggs in thistle flowers. Anyone know for sure?