A young Myrmica queen searches for a nesting site following her mating flight. Clinton Lake Recreation Area, Illinois, USA
Mystrium voeltzkowi has an unusual caste system. These unusual ants are dimorphic, with a small red caste that appears to work mostly in the brood nest and a larger, dark caste that performs most of the foraging and guarding of the nest. Interestingly, the ants that perform as reproductive queens are drawn from the smaller caste. Madagascar
