Wow...can Nanitics even live that long?? Yep it's likely something to do with your temperature. If it's too low, ants will grow reaaalllly slowly, or not at all. You can probably boost their food intake to a whole mealworm every four days or so, until the next generation arrives.
Manica invidia (1 queen, ~200 workers)
Manica invidia (1 colonies, 1 queens plus 3 workers)
Lasius niger (single queen, ~200 workers - naturalistic, predatory set-up)
Lasius americanus (1 colony, ~10 workers)
Tetramorium immigrans (3 colonies, 3 queens, ~ five workers each | 1 colony, 1 queen, ~1200 workers)
Formica aserva (aserva queen, ~15 ​Formica neorufibarbis workers)
"And God made...everything that creeps on the ground according to its kind.
And God saw that it was good." - Genesis 1:25