Myrmecia varians is a monogynous ant species with a colony size of up to 1000 workers. The ants have a medium development rate and the queen measures 17-19 mm while the workers measure 14-17 mm. They are black and dark brown in color and feed on food insects, syrup, and fruits. They require a humidity level of 50-70% in their arena and 60-80% in their nest.