The name Sipho was much used until the latter part of the 20th century for species now placed in Colus and other buccinid genera. Historically, the name Sipho was first used by Klein (1753; pre-Linnean) for a number of slender neogastropods. Klein's classification was presented, but not adopted, by Bruguière (1792) in the Encyclopédie Méthodique, and this does not constitute a validation of the name Sipho.
In the literature, the name Sipho has also been attributed to Fabricius (1823), but in that work it was associated with specific epithets which are all nomina nuda. In addition, Fabricius' work of 1823 (Fortegnelse) has been placed on the Official Index by ICZN Opinion 521.
In fact, the first author that validly used Sipho for buccinids was Mörch (1852). However, in the meantime, Thomas Brown (1827) had used Sipho for Sipho striatus T. Brown, 1833, a synonym of the fissurellid Puncturella noachina (Linnaeus, 1771).
To summarize, there are two Sipho, none of which is valid:
(1) Sipho T. Brown, 1827, a synonym of Puncturella;
(2) Sipho Mörch, 1852 [ex Klein], a synonym of Colus.
The buccinid word sipho survives as a suffix in several buccinid genera, such as Anomalosipho, Prosipho or Turrisipho.