I have looked all over your site and others that are linked but haven’t been able to figure out what this critter is. This photo was mailed to me and I am told that the bug measured about two inches by one inch. It appears to be just a skeleton found on a board covering the crawl space to a camp in the Adirondack Mtns. Thanks for any insight you can provide.
This is the shed skin from the final moult of a Dragonfly Naiad. Naiads live under water. They moult several times to fascilitate growth since the exoskeleton cannot grow. At the time of the final moult, the Naiad climbs out of the water and sheds its skin, becoming a winged adult. This Naiad might be from a Common Skimmer based on the shape of the abdomen.