The Buccinidae are a very large and diverse taxonomic family of large sea snails, often known as whelks or true whelks. The family includes more than 1500 species. Taxonomy The family Busyconidae was for a time treated as a subfamily of Buccinidae called Busyconinae. Genera Antillophos, Engoniophos, Phos, Nassaria, Tomlinia, Anentome and Clea were treated within family Buccinidae, but they were moved to Nassariidae in 2016. Habitat The true whelks occur worldwide in all seas from tropical oceans to the cold seas of the Arctic Ocean and the Southern Ocean. They are found from the intertidal to the bathypelagic zones. Most prefer a solid bottom, but some inhabit sandy substrates. Description The shells of species in this family are moderate to large in size, conical to fusiform in shape. The shell often has deep sutures. The shell surface is generally smooth, sometimes with a spiral and/ or axial sculpture. The thickness of the shell is more pronounced in tropical shallow-water species, while the shell of species living in moderate and colder waters is generally thin or moderately thin. The top of the whorls are more or less shouldered. The radial ribs of the shell sometimes show shoulder knobs. The aperture is large with a well-defined siphonal canal. The rim of the aperture is sometimes used to pry open the shell of bivalves. The aperture is closed by a horny operculum. The soft body is elongated and spiral. The head has two conical, depressed tentacles which bear the eyes on a lobe or prominence at their base. The mouth contains a long, cylindrical, annulated proboscis and a small tongue. The mantle forms a thin-edged flap over the branchial cavity. On the left side, it has an elongated, open canal, that emerges by a notch or groove in the shell. The two gills are elongated, unequal and pectinate (i.e. in a comb-like arrangement). The large foot is generally broad. True whelks are carnivores and scavengers. They feed on clams, carrion, and sometimes even on detritus. Their sense of smell is very well-developed; they can sense chemical signals from their prey from a considerable distance with their osphradia. Many whelks are capable of boring through the shell of bivalves, and because of this, some species cause much harm in oyster farms. True whelks can even attack fish caught in a net by extending their probosces to twice the length of their own bodies.