Sipho is a genus of sea snails, marine gastropod mollusks in the family Buccinidae, the true whelks.
The name of the genus Sipho Mörch, 1852 [ex Klein] has become invalid and is a synonym of Colus Röding, 1798. A previous use of the genus name Sipho T. Brown, 1827 is now a synonym of Puncturella [1]
All the species that used to belong to the genus Sipho have become synonyms of other species in the family Buccinidae.