Summer azures have multiple, overlapping broods in Iowa, according to The Butterflies of Iowa by Schlicht, Downey, and Nekola. These seem a little worn and battered.
In the world of tiny butterflies these are no spring chickens. In fact, they are a little long in the tooth…or maybe long in the proboscis. But that does not stop them from chasing each other around.
A third individual joined the chase briefly but I was not fast enough to get a good photo.