Norway to Morocco, Azores to Alborán Sea. Scavenger and predator on soft sediments, from the shallow water (north) down to continental shelf and slope. Original taxon: Fusus jeffreysianus. Synonyms: attenuatus, gracile, propinquus… The shell is a bit more globose than in Colus gracilis.

« During a cruise of the “Michael Sars” in 1902, the lines on the Faroe Edge yielded a large number of molluscs (Sipho glaber, or a very similar form), which attached themselves to the bait… » – Murray & Hjort: The depths of the ocean, London 1912, p.508. The species is sometimes the voluntary host of some Actinians, such as Hormantia digitata (O. F. Müller, 1776).

Despite its name, Colus gracilis is bigger, more solid, with stronger sculpture and less spiral ribs; normally it develops a thick labial lip and the siphonal canal is very short compared to that of jeffreysianus.

In the NE. Atlantic Colini, the northern populations are often less slender, thicker, with a rougher spiral sculpture and a larger suture than their southern relatives. « Sufficient intermediate populations are found in between them to recognize both forms as the extreme units of a cline. A similar cline can be recognized between populations in shallow water (usually a thick shell) and deep water (smaller and thinner shells), however exceptions are found » (Fraussen & al., 2009).