1) Guttule 
Guttula is a genus of sea snails, marine gastropod mollusks in the family Seguenziidae. (Original description by Schepman) The small, shell has a conoidal shape. It is smooth, pearly, and perforate. The aperture is rounded, with an angle at the base. The operculum contains few whorls. It is chiefly on account of the peculiar radula, that Schepman ...
guttule, guttula 1. A small drop. 2. A spot like a small drop.