Green turtle
The quickest way to determine if the turtle is a green turtle is to examine the scutes on the head. If it has a single pair of elongated scutes on the forehead its a green.
Identification chart reproduced with kind permission from the Research and Management Techniques for the Conservation of Sea Turtles.
Identification chart reproduced with kind permission from the Guide for the Identification of Stranded Sea Turtles: Eastern USA and Gulf of Mexico.