Mo. Rev. Stat. § 273.150

Every owner of a dog and every person who shall suffer or permit a dog to remain upon such premises under his immediate control without having caused such dog to be listed and the tax thereon to be paid as provided for by sections 273.040 to 273.180 shall be guilty of a misdemeanor, and on conviction thereof fined not less than five dollars nor more than twenty-five dollars; provided, that none of the provisions of sections 273.040 to 273.180 shall apply to cities which now have or may hereafter have a population of three hundred thousand inhabitants or more.