Tritia corniculum, common name the horn nassa, is a species of sea snail, a marine gastropod mollusk in the family Nassariidae, the Nassa mud snails or dog whelks.

[2] Originally introduced in the binomen Buccinum corniculum, the specific epithet is to be considered a noun (meaning "a small horn on a soldier's helmet") and is invariant.

The aperture is pretty large, ovate, violet-colored or chestnut, and dilated towards the middle.

The epidermis is thin, of a greenish- or reddish-brown, and beneath are perceived transverse zones, with spots of a slate- or violet-gray color, along with a decurrent white band, articulated with brown or bay-colored spots upon the suture.

[3] This species occurs in the Mediterranean Sea and in the Atlantic Ocean off West Africa and the Azores.