†Neoplanorbis smithi was a species of small freshwater snail, an aquatic gastropod mollusk in the family Planorbidae, the ramshorn snails. This species was endemic to the United States; it is now extinct.The shells of this species appear to be dextral in coiling, but as is the case in all planorbids, the shell is actually sinistral. In life the shell was carried upside down with the aperture on the right, and this makes it appear to be dextral.