Vanitrochus tragema
Vanitrochus tragema is a species of sea snail, a marine gastropod mollusk in the family Trochidae, the top snails.
Description
The size of the shell varies between 1.8 mm and 4 mm.This is a small conical chalky-white shell, colourless excepting for scattered transverse pink flames round the upper parts of the lower whorls just below the sutures. The shell is profoundly but narrowly umbilicate. The shell contains six whorls six, two being in the protoconch, slantingly angled in a gradate manner. The surface is closely acutely ribbed, the transverse decussations somewhat noticeable in the interstices, and these in some specimens give a crenulate appearance to the ribs themselves. The base
is spirally costulate, as are the upper whorls. The aperture is round. The outer lip is simple.