Almost all of the pics I've ever seen have shown them either having that blueish/green back half...or a dark olive green.
Any that I've ever seen in person, have either the olive green to a light green, such as the one in my pics.
They're pretty much my favorite fish...after my Hawaiin Dragon, that is.
The one pictured above is no longer with us, unfortunately. I put my Dragon and Whitemouth Morays in the tank, at the store, while I was working on my own. The Orange Shoulder, Imperator Angel (10") and another fish mysteriously died from having their stomachs ripped open. Although neither of my Morays have ever shown the slightest bit of aggression towards other fish and none of the fish mentioned were "eaten", I think my Morays got a little angry because my friend wasnt feeding them properly.