Whoever named the blue dasher dragonfly (Pachydiplax longipennis) clearly hadn’t seen a female; this female has almost no blue on her whatever. The males, of course, have bright blue abdomens, a green striped thorax, and green eyes.
Blue dashers are “perching” dragonflies; they regulate their body temperature by basking in the sun. If they really need to soak up the rays they will tilt their abdomens firmly upward in the descriptively named “obelisk posture”, maximizing the amount of surface area turned toward the sun. They stay still and wait for prey to come within range, then rush in to catch it. They eat almost anything, and can consume up to 10% of their body weight in food each day.
Adults are 25-43 mm long. The species name, longipennis, technically means long wings; the blue dasher’s wings are proportionally about the same size as any other dragonfly’s, but the females have somewhat shortened abdomens which make their wings look longer.