Your first suggestion sounds a lot like V and I love it. 

I have another suggestion. It could be that they lived in deep jungle etc and kept to themselves. But that jungle could have been largely destroyed in the magical nuclear heat. And since the bombs fell the Lizard folk have had to come out of their seclusion and rapidly adapt to the more modern world. Could make for interesting character dynamic and confusion. But I don't know if [@Rydude17] would approve of this BG either. Just a thought.