Tritia frigens
Tritia frigens is a species of sea snail, a marine gastropod mollusk in the family Nassariidae, the Nassa mud snails or dog whelks.
Description
The shell grows to a length of 15 mm, its diameter 6 mm.The shell is ovate, sculptured with smooth, subvertical ribs that are doubly distant in their interspaces and appear nodulosely-abrupt upwards. It also features impressed lines, which are sparse above and more frequent below. A broader, opaque, whitish infrasutural lira is present.
The shell comprises 5-6 whorls, divided by a subcanaliculate suture. The aperture is ovate and slightly oblique, featuring a simple, unarmed white peristome. The inner margin is expanded into a narrow, subelliptic callus superiorly.