Mo. Rev. Stat. § 243.490

If any county collector of the revenue refuses, fails or neglects to make prompt payment of the tax or any part thereof collected under this chapter to the county treasurer as provided in said chapter, then he shall pay a penalty of ten percent on the amount of his delinquency; such penalty shall at once become due and payable and both he and the sureties on his bond shall be liable therefor on his aforesaid bond.