Southern and Slender Spreadwings are both abundant in Maryland. For the males, an easy way to distinguish between them is by abdomen (body) length.
Photo on right: dorsal (top) view of male. Abdomen looks almost twice as long as the wings. Slender Spreadwing male's abdomen is very thin and looks almost three times the length of the wings.
Photo below left: side view of male. Note powdery blue coating on lower thorax and tip of abdomen. This is called pruinosity and develops on many damselflies as they mature.
Photo below right: Closeup of male's appendages at end of abdomen. Cerci (outer pieces) come together to form an oval shape. Paraprocts (inner pieces) extend out nearly as far as cerci.
If you get a good enough look, shape of appendages is the most reliable way to ID spreadwings.
