I don't know whether it's really possible to tell by looking at a photo. I may be wrong, but I believe that there are scale counts that could confirm which one. I have bred C.v.v. to C.v.b. and labelled them as C.v. I did that because the male C.v.v. I was breeding came from a locale where the geckos are white and beige instead of yellow and beige and I figured if C.v.v. specimens could look that different from each other, it wasn't a great tragedy to go through with my planned pairing.
Aliza