sentence1: Atalacmea multilinea is a species of sea snail or genuine limpet , a marine gastropodemollusk in the Lottiidae family , one of the families of true limpets .
sentence2: Atalacmea multilinea is a species of sea snail or true limpet , a true gastropod mollusc in the family Lottiidae , one of the families of marine limpets .