Moved from Lestes.

Of the four possibilities in your area, the two most remote possibilities Lyre-tipped (only 3 OK county records) and Slender Spreadwings are eliminated by the very broad terminalia in this female. Slender is further eliminated by the dark dorsal surface of S10. Of the remaining two likely candidates, based on range, Southern and Plateau, the jagged edged mid-dorsal stripe of the thorax eliminates L. alacer (which is perfectly straight) leaving you with L. australis Southern Spreadwing.

BTW, as of this writing there is no official record of the species
for Osage County (although known from 3 adjacent counties).

Helpful source here is John Abbott's D & D of Texas and the South-Central States. See also http://odonatacentral.org/

Female Spreadwing, not sure I can say more.