Malabar Farm in Richland County, Ohio. I was up this way last Friday and Saturday to help with the 7th annual Flora-Quest, which was based out of Mohican State Park. We had a great time, and the event was superbly organized courtesy of Cheryl Harner, Paula Harper, and everyone else who was involved.
Saturday's main activity was field trips at legendary Malabar Farm. I was stationed at a small wetland known as Junglebrook, along with some expert naturalists such as Lisa Rainsong, Judy Semroc, Mark Dilley, and Larry Rosche. Various F-Q groups were shunted our way all day long, and we'd lead them about looking for interesting things.
We focused heavily on the flora, as after all this was a botanical event. The bright flowers of the aforementioned Green-headed Coneflower always drew comment. The plants' robust stature and colorful blossoms could not be missed.
It was an easy guess that some sort of insect was causing these galls, as various flies, wasps, moths and other bugs routinely cause large galls in plant tissues. But none of us had a clue as to exactly who the culprit was. I recall seeing such galls before on Green-headed Coneflower, but not often enough to recall specifics of where and when.
Enter The Google. Judy Semroc had her iPhone along, and had a connection. A few smartly chosen keywords in Google, and we had an answer. The galls were caused by a midge known as Asphondylia rudbeckiaeconspicua, a name much longer than the little fly that it denotes. I'm not sure what the genus name means, but the specific epithet is clear: rudbeckia = genus of the midge's host plant; conspicua = conspicuous.
What was not expected (although perhaps it shouldn't be surprising) was another occupant of the gall. As I attempted to make images of the grub above with my macro lens, I was startled to see a tiny insect clamber out of one of the inner chambers of the gall. While I got one or two OK images of this other bug in the field, it was really too small for my 100mm macro. So, I pocketed five galls, and took them home for more detailed autopsy, and images with Canon's incredible mega-macro lens, the strange MP-E 65mm. The photos that follow were taken with that lens, coupled to the Canon 5D Mark III with illumination via Canon's MT-24 Twin-Lite flash system.
I think we only dissected one gall in the field, and it held at least one wasp. Of the five that I brought home, wasps were in four galls. It would appear that the incidence of parasitism, at least in this midge gall colony, is high.
If one is willing to look at Nature with a broadly sweeping eye, the little mysteries just keep on coming.