Female Fall Cankerworm
I found this wingless insect hanging on an outside wall at work on October 30, 2015. Its body was just about half an inch long.
Aside from the complete lack of wings, its body looks like some kind of moth.
And it definitely has a moth-like face and antennae.
It was very inactive, its only defensive maneuver was evidently to scrunch up and play dead.
Checking under “wingless moths”, the best match for our area looks to be the Fall Cankerworm, Alsophila pometaria. These are geometrid moths, with inchworm-type caterpillars. And, they are also extremely sexually dimorphic, with the males having full-sized wings and being reasonably strong fliers, while the females look like this.
There are a fair number of moths where the females have gone wingless. While this would seem to be a bad idea, since it dramatically reduces the mobility of the females, it does have one fairly substantial advantage: by eliminating the wings and their associated musculature, the female moth can devote more of her body reserves to egg production.
The caterpillars eat the leaves of a lot of the usual trees – maple, ash, oak, various plants in the rose family, and the like. They pupate in the soil, and emerge late in the fall (right around Halloween, evidently). The female hangs around in a likely spot until a male comes by to mate with her, and then she lays a whole mess of eggs that overwinter. There are some reports that if a male doesn’t come by, she may be able to just reproduce parthenogenically and lay her eggs anyway.
Since the female doesn’t have the wherewithal to travel much, her offspring are going to be on their own as far as colonizing new areas. The males can get around pretty good, but they obviously aren’t going to really contribute to spreading the species around because they can’t do anything about moving the eggs to new places. In some climates the caterpillars are major tree defoliators, but not everywhere.
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It looks frosted. Mmmm. Frosted Canker Worms! Now with 12 essential vitamins and minerals!
Merry Christmas, amigo. I hope you and your family are having a great day.