Of the two common species here, Veromessor pergandei, are probably the most abundant ant in the desert. They are pretty much everywhere out there, and they are also active pretty much year round, no matter how cold or how dry it is. I've also found them a lot in desert scrub foot hill areas like most of Riverside County.
The other of the common species here are Veromessor andrei, which I have found in the foothills all over Southern California, even right near the coast in Laguna. The only place I don't find them is in the desert.
I have had plenty colonies of V. pergandei, but V. andrei I have never had, which is why I really want them.