Elm Sawfly
I found this large insect mostly dead (it was still twitching) in the road on June 27, 2014.
By “large”, I mean about an inch long, as we can see by comparing it to my thumb and forefinger:
It was in kind of rough shape from its presumed encounter with a car, but still had one orange antenna left.
The mandibles are fairly pronounced, and look like the shearing type.
On the underside, the legs are dark, and look quite strong.
I believe it is an Elm Sawfly, Cimbex americana, the largest sawfly in North America. The pictures I’m seeing usually show it with a black abdomen, although there is a varying amount of orange, and sometimes it is as orange as my specimen. And the “beefy” legs are evidently a trait of the males. The dark legs, orange antenna, and the pale spot where the abdomen meet the thorax all look right. In spite of its name, its larvae are not restricted to elm (which I don’t believe we have any of on our property). They also eat leaves from maple, birch, willow, and basswood (all of which we have plenty of).
Although it is quite large and has a somewhat sinister appearance, I believe that these are harmless (although it looks like they could possibly bite if provoked). The larvae are great big things about two inches long, that curl around the twigs of the trees they are eating. The larvae also have chemical defenses, ejecting noxious fluids from glands near their breathing spiracles if provoked. They can evidently get numerous enough sometimes to defoliate trees, although apparently not often enough to be considered a serious forestry problem.
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Excellent photography. Unworthy subject. The fellow looks like he fell, face-first, into some tar.
Well yes, it isn’t really a thing of beauty, but then I doubt that I’d make a particularly good-looking corpse after being hit by a car, either.