A couple of challenges: small, the big ones are in the 7-10 mm range; the obvious mound builders are at ground level; the ants 'never' keep still; best shots to get a positive ID has to include a lateral view.
So, no shooting from above, one has to get down to an ant-eye-level (problem is getting back up!)
The easiest part is to slow the ants down, simply place a dop of honey or preferably (for them) a piece of fish on the nest. They will stop to eat. Fish (protein) seems to be preferred over sugar but they tend to drag away the fish, sugar they simple suck it up.
I probably push my equipment to the limit for these subjects:
Nikon D810 + TC1.4x+PN11 extension tube+200mm macro+5T closeup lens; at minimum focus I can get 3x magn. Set the 200mm at its minimum f/32, flash. Single exposures
Ulke's Ant, Formica ulkei
