Large yellow ant queen
Jeff Hahn, University of Minnesota Extension
Description: 1/4 inch long. Yellow with smoky brown or amber wings; one-segmented petiole.
Where/When: Yellow ants nest in the soil under objects, including concrete slab construction of homes. Winged large yellow ants can be found in homes April through September as well during winter.
Significance: Seeing winged yellow ants indicate a nest in the home. The presence of a nest is not damaging to a building and the presence of winged ants is just a nuisance.