I would love to be drawing this myself. Those textures are just made to be drawn!And, as usual, you're making a superb job of this. I particularly love the pose. It looks so natural and uncontrived -- by which I mean AWKWARD
I think it would be impossible to engineer or invent such a pose.
I do have one criticism. "Eyes closed". If you're used to lizards this might work just fine but I'm not and it isn't... 
I find the drawing of the head rather weak in comparison to the body and it's not helping my understanding. I can see what I think is the mouth and what is possibly a nostril? And a marking that looks like an open, featureless eye... but the closed eye eludes me. Unless it's what I think might be a nostril. Basically, this drawing is not "idiot-proof" .... and I'm the idiot who can't read it at all well 
...or maybe that round marking is the eye with the lid down...? Not knowing Lizards, I don't know where to expect the eye to be.
But I do think the eye is the central, controlling element -- the one that should be telling me "this animal is asleep"... and, for me, it's not working.
I love the composition. Do you have plans for the big negative area at the left? Vague foliage? Nothing?
MIKE
www.SibleyFineArt.com
www.Starving-Artists.net