On the evening of May 11, 2014, I noticed a dragonfly, my first of the year, hunting alongside a coastal nature trail in Biddeford, Maine. When the creature paused for a few minutes on a tree branch, I took the opportunity to take a close look and snap these photos. Consulting a field guide later, I determined this was a Common Green Darner (Anax junius).
Both males and females have green thoraxes, yellow lines on the leading edge of their wings, and distinctive "bull's-eyes" in front of their eyes. I'm not sure of the sex of this individual, but I'd guess male based on the eye color (females apparently have solid brown eyes). Common Green Darners migrate to New England each spring and arrive earlier than most other species.
I shared a flight photo of a male Common Green Darner last fall.
Source: A Field Guide to the Dragonflies and Damselflies of Massachusetts by Blair Nikula, Jennifer Loose, and Matthew Burne (2007)