Mo. Rev. Stat. § 55.130: Shall countersign all warrants (second class and certain first class counties).

The county auditor of each county of the first class not having a charter form of government and of each county of the second class shall countersign all warrants issued by the county commission, and shall keep a record of the date thereof, the number of same, to whom issued, the amount thereof, and upon what fund drawn.