Eastern Pondhawk Dragonfly

Female pondhawks, are bright, vivid green with green faces and black markings along the abdomen. Males, are the same color when they first emerge as adults, but over time they build up a waxy layer that turns their bodies a dusty blue. Underneath the wax, however, they look just like the females! When the males and females of a species look very different, scientists call them sexually dimorphic. Dimorphic means "two forms," so sexually dimorphic means that males and females are different. Many other dragonflies are sexually dimorphic too!

http://naturalsciences.org/prairie-ridge-ecostation/what-time-is-it-in-…