This species of Polyergus from the Mississippi Valley keys to "breviceps", but there appear to be two species in the region that key out to this. One is more northern, smaller and more pilose and has F. montana as its host (this one resembling the types of breviceps). The one pictured here is more southern, but broadly geographically overlapping in the upper Midwest, without morphologically intergrading with true breviceps. It is a notably larger and less pilose form that lives with F. subsericea as far south as Arkansas.