I found this little spud while down at the nearby pond chasing its older brethren. This is a juvenile green treefrog, or to be more precise, American green treefrog (Hyla cinerea) and it's tiny, between 10 and 15mm in body length. It has probably not been very long since emerging from the water and its tadpole stage, and the tail has just disappeared.
They all have skin this iridescent, but you normally don't see it this close – this specimen is probably about the length of just the head of a full-grown adult, and green treefrogs are not large frogs at all. I was very lucky that it was complacent enough for the close approach necessary to get this shot. Even at this range, the limbs are tucked in so tightly they appear to be mere lines carved into the body.