This is an Aurora Damsel. I am cheating a little here, because I photographed this damselfly in Michigan rather than Ohio. (These two Aurora Damsel photos, and two of my Luna Moth photos, are the only photos on my website not taken in Ohio.) We have Aurora Damsels in southwestern Ohio, but there are only a few records. Aurora Damsels are much more common in eastern Ohio. This species typically flies in May and early June in Ohio.  

Aurora Damsels have a distinctive black shape on the top of their thorax, shown here. They also have yellow on the sides of the thorax, and they often hold their wings partially spread like a spreadwing. (In fact, I thought this Aurora Damsel was some type of spreadwing when I first saw it, until I looked more closely.) 

Male Sphagnum Sprite. These sprites are some of our tiniest damselflies. They live in good quality wetlands. I see numerous Sphagnum Sprites at Siebenthaler Fen in June and early July.  

Sphagnum Sprites can be difficult to find due to their small size. They lurk in dense vegetation. Their color pattern is somewhat reminiscent of an Eastern Forktail (green in front and blue at the tip). I have trained my eyes to ignore damselflies with this color pattern, because Eastern Forktails are so ubiquitous. But seen close at hand, the two species are really not that similar. (Eastern Forktails are larger and have stripes on the thorax.)

This is a female Sphagnum Sprite. She has less blue at the tip of her abdomen. Female Sphagnum Sprites look very similar to male Sedge Sprites. (I have not yet seen a Sedge Sprite, but they are known to occur in our area.)