To our surprise, about 10 p.m., this dragonfly showed up and stayed until we packed up at just past midnight! It was quite large and very lovely but we couldn't immediately put an ID to this night-flying odonate! However, thanks to Chris Lewis, we learned that this was a Prince baskettail. Apparently it has several wing pattern variations and this one didn't fit the usual description which caused confusion when trying to ID it. Chris says it is a crepuscular species but it is very unusual to see it out late at night.