Hi John . I am THINKING(not 100% sure) your guy is probably an all black Uromastyx dispar flavifasciata. I think the common name is banded uro. Not rare but not common for the species. A few come in from time to time. Some people were trying to call them alfredscmidti but the origin is no where near the range of alfreds plus I think the scalation is not right etc. I think they get a little bigger than maliensis but like maliensis and dispar it is a subspecies of dispar. Hope this helps.

Tom Greb