One heck of a beetle

Recently, I spent a perfect late-summer day in south-central Ohio with some folks who are keen on insects. Eight of us got together in hopes of finding a show-stopper of a beetle that is not well-known in Ohio. Our story starts right here, along the banks of the Ohio River.

Hello over there, Kentucky!
Before I go any further, let me just say that I am thankful that there are other folks out there who are willing to travel a few hours just to see one small insect. Some (okay, many) would call us crazy, and others would call us nerds. These are descriptions we would all agree to with a smile on our faces. Everyone has a special interest or two that makes them happy, and for which they would drive long distances to indulge. For some of us, that special interest is being outside, searching for new and exciting things, whether they be birds, flowers, or insects.

And so, back to our quest. Several hundred yards from the river proper is where we found what we were looking for. And what, exactly, WERE we looking for? Three years ago John Howard stumbled upon a beetle he didn't recognize, and it was very close to this area. John knows his insects, so for him to say he found something that he didn't recognize is saying something. Eventually some photos got posted to bugguide.net, where the knowledgeable folks there identified it as Megacyllene decora, or the Amorpha Borer Beetle. It gets its common name from the Amorpha plant that it bores into in order to lay its eggs.

Amorpha fruticosa, or False Indigo - host plant for the Amorpha Borer Beetle, seen here in flower.


As shown on this map from the USDA Plants Database, the plant has limited distribution in Ohio, occurring in only 5 counties in the southern half of the state (it's slightly more prevalent in northern Ohio, where it has been introduced). One of those southern counties is Scioto County, and that is where we spent our time along the river looking for the beetle. Or maybe I should say The Beetle, capital "T" and "B," since it seems to be a rarity for Ohio, and I'm all about seeing rarities first-hand. I remember reading about The Beetle on Jim McCormac's blog last year, and was delighted to be part of the search party this year. (To read Jim's account of this year's expedition, click HERE.)

I had an idea of what we were searching for, so my pulse quickened when we came across this beetle on late-flowering thoroughwort, Eupatorium serotinum. This, however, is not The Beetle. This is a Pennsylvania Leatherwing, Chauliognathus pensylvanicus, which is somewhat similar in markings to The Beetle, but smaller, and not as brilliantly colored.

Here is the charmer that got us all hootin' and hollerin', Megacyllene decora in the flesh!

This may not look like much, but it is a very large, shrubby late-flowering thoroughwort, a plant which was in abundance, and which is used by the Amorpha borer as a nectar source.

Here you see part of our group gathered 'round in order to thoroughly document and absorb the awesomeness of this cool beetle.

In case you're curious about the scale of things, the beetle is the tiny yellow dot in the middle of the purple flower in the center of this photo. I can't help but wonder how that beetle must have felt to see all of these huge bipeds with third-eye appendages and large flashing lights bearing down upon it.

And now... the star of the show! We decided to pose it on ironweed to provide a nice contrast to it's spectacular coloring.

Megacyllene decora posed on tall ironweed.

The true work of any naturalist, amateur or professional, is to spend time with their subject and observe it. One should make every effort at getting to know it and its habits, even if it is only for a few brief minutes. Being able to catch something as basic and elemental as grooming behavior, as seen here, was a real treat.

I don't know if the beetle really was mad or not, but this close-up certainly makes it look that way to my anthropomorphic sensibilities.

As to its awareness of us, well, it definitely had an eye on us. Being flanked on all sides by cameras held at very close range, we are lucky that this isn't an insect with a more aggressive defense strategy (as in, going for your eyes or squirting flesh-eating fluid from its nether regions). As far as we know, the main thing to fear from the Amorpha borer beetle is being munched by its mean-looking mandibles, but none of us tested those chompers, so I don't know what the real affect would be from that. Regardless, when an insect is eying each of its hunters, as The Beetle appears to be doing here (there was a camera to my immediate right, exactly in line with his gaze in the photo at right), you best not try messing with it!
I can now say that I have observed first-hand the appeal of this beautiful beetle, but the rare nature does beg some questions. While John Howard discovered this stronghold 3 years ago, no one has managed to find more than 2 individuals of this species in this area since the initial discovery. Two questions arise in my mind from this: 1.) Why are there so few of them around (compared to the leatherwings and other insects that we found in abundance)?; and, 2.) Why are they so localized? Well-known bug guy Eric Eaton says he lived in Cincinnati for 11 years and only came across this bug once. Intrepid nature explorers, ALWAYS keep an eye out. I know I will be out and about looking for this beetle next year, hoping to find another population.