Just look at those gorgeous green eyes! 

This Swift River Cruiser was perched high in a tree. These dragonflies are fairly common in our area. I see them flying at numerous locations, including the Great and Little Miami Rivers,  Germantown MetroPark, Twin Creek MetroPark, and Caesar Creek. Yet this is one of our most challenging dragonfly species to photograph. They rarely perch for photos, and when they do, they are usually high in a tree. 

This is a newly-emerged, teneral Swift River Cruiser. I found it early in the morning, on the banks of the Great Miami River near Miamisburg. 

Swift River Cruisers have brilliant green eyes and a single yellow stripe on the side of the thorax. They also have a bright yellow spot on the top of the abdomen (just above the club). There are two subspecies of Swift River Cruisers. The one in our area (sometimes called the Illinois River Cruiser) is less brightly marked than Swift River Cruisers in the south. 

Swift River Cruiser, photographed just south of Crain's Run Nature Park (near Miamisburg). These large dragonflies are swift fliers, and they patrol medium to large rivers and creeks

Swift River Cruisers fly from June through early September. 

This dragonfly is a female Royal River Cruiser, photographed at Caesar Creek. She is a little beat up (damaged wing and abdomen). But I was so delighted to FINALLY find one of these dragonflies perched  that I didn't mind.  She is perfect in my book! 

Royal River Cruisers have several pairs of tiny yellow spots along the abdomen. This distinguishes them from Swift River Cruisers. (But both species have mesmerizing green eyes!) 

This is a male Royal River Cruiser, patrolling at Cowan Lake. The abdomen tip is not clubbed (as opposed to Swift River Cruisers, which have a noticeable club). The name "river cruiser" is misleading for this species. I see Royal River Cruisers at large lakes far more often than on rivers. They fly mainly in July and August, with stragglers into September.