If I have identified this reptile correctly he is a Northern Mesquite Lizard (Sceloporus grammicus microlepidotus). That vivid turquoise splash on his throat is what distinguishes him from the females of his species.  He lingered just long enough for me to snap a quick photo before dashing off into the underbrush. The white blotch on the back of his neck is a bit unusual, perhaps a bit of leucism?