Gibbula umbilicaris: The bright aspect of surface is a characteristic of this species. Shell solid, conic in form, sharp apex, whorls not much convex, suture deep and canaliculus. Last whorl roundish with a convex base. Umbilicus very wide and careened, columella straight making one right angle with the external lip, aperture subquadrangular, pearly. Sculpture made by thin spiral little cords narrow and flattened present at the base too. Typical ground colour pattern dark brown, with flammulae and stains more or less evident, white in colour, placed below the suture and on the periphery of the last whorl. At the base there are present dots dirty white. Operculum corneous, thin and multispiral. Periumbilical area brown in colour. Juvenile forms have one clear carina on the periphery of the last whorl. The adult specimens average measures are around 20 mm in diametre.

Gibbula umbilicaris: The varieties in form and in colour are numerous (Monterosato, 1888; B.D.D., 1884; Tapparone-Canefri, 1869; Pallary, 1912, 1920, 1938). Particularly we would like to quote variant latior (Monterosato. 1888), endemic of Gabés Gulf that, compared with the nominal species, is bigger in sizes, less elevated in spiral, less solid, base plane and whorls less convex with clearer cords, wider umbilicus. Gibbula nebulosa (Philippi, 1848), considered as a distinct species by some authors, is quoted by CLEMAM as synonym of G. umbilicaris. This form, present in the Eastern Mediterranean, is more elevated in aspect, smaller in sizes and reddish white dotted in colour pattern.

Gibbula umbilicaris: Mediterranean, more common in the Western basin. It lives under stones, on algae and in meadows of Posidonia oceánica, in the infralittoral zone.