If your referring to queens then you may be out of luck as they tend to fly early in the year and may have had there nuptial flight, also they don't make a great species to keep in captivity as there nest grow very large and there tendancy to squirt Formic acid can kill them if in a confined space (not to mention it smells funny).
Some of my messor barbarus when they arrived (in a different set up now)
Although titled messor barbarus digging it's more targeted at the super majors but this is what I'm keeping them in now
A better part 2 of messors digging is comming soon. ;D Soon to come
Lasius Niger Formica rubra
Formica lemani Myrmica rugonodis
Current Colonies: Solenopsis invicta, Messor barbarus, Pheidole noda, Pheidole spathifera, Tetramorium simillimum, Camponotus japonicus, Camponotus barbaricus, Camponotus nicobarensis, Crematogaster biroi, Formica fusca, Formica lemani, Mymica sp.