Two quite similar darter species of dragonfly are the Common Darter and the Ruddy Darter. They are both found in good numbers at Maxey gravel pits, where the above photos were taken.
The Common Darter is in the first 4 photos, the first 2 are of a female (I think) and the other 2 are of the male. The last photo of the Common Darter shows how similar it is to the male Ruddy Darter, which is in the next photo. The Ruddy Darter is told apart by the waisted blood red abdomen and the all black legs, both features that the Common Darter doesn't have.
The flight season of these two dragonflies can last until late Autumn, even after the first frosts, it is lack of food that eventually kills these beasts rather than cold nights.