Though the books (and the pictures already here on BugGuide) show a darker face, young females can have a white face like this one (personal communication from Dr. John Abbott earlier today). This dragonfly perched fairly low, choosing dead "stubs" of flameleaf sumac within 2 feet of the ground. Though I startled it initially, it returned to one of three perches repeatedly, allowing plenty of time for photography. The only thing it wouldn't do is hold its wings straight out for more than an instant, so it was hard to get a clear shot of the markings on the side of the thorax, since the dark spot near the base of the wing covered that area from most angles.

You can see that the markings on the front of the thorax are brown, not black; the face is white, not olivaceous or brown; and the abdomen seems to have more white and less black than in most photographs of this species. I'll be linking another image of this dragonfly in a few minutes. I do have one "wings straight out" shot, if anyone thinks it needs to be here, but it's not the characteristic posture.