I originally thought this was a Canada Darner but Ben Coulter, a Contributing Editor at BugGuide.net was able to correct me with a good summary of how he knew it was a Shadow Darner. He wrote, "This is a Shadow Darner (Aeshna umbrosa). The thoracic stripes are straight, and the anterior one is shaped like a numeral 7, while it is deeply notched on Canada, and the dorsal flag is thinner. They are also green, while they are normally at least partially blue on Canada. Canada also usually has a yellow spot between the stripes, which this individual lacks. On the abdomen, the dorsal spots are too small for Canada. Of the eastern Aeshna, only Shadow has such reduced markings. The cerci are also rotated vertically, and with a terminal spine on Shadow, while they are ski-shaped on Canada."