Welp, I think this picture pretty much sums up the comment on the info page for this species (Isn't that smaller worker adorable???) :
Remarks
Workers of this species are tiny, about 1.25 mm in length, until they fill up their crops with honeydew from subterranean aphids, etc. and expand to nearly 2.0 mm. [comment by James C. Trager]

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For this picture, I dug up a colony of these ants, and then put most of the workers in a container, and carefully picked out the one that looked smallest to the naked eye, and the one that looked largest. I must say, for such a tiny ant, their nest was quite extensive (just in claylike soil), but after 3 hours of digging 6 inches into the ground with a pair of tweezers (trying to follow their tiny nest chambers) I finally found the queen.