Alvania ignota


Alvania ignota is a species of minute sea snail, a marine gastropod mollusk or micromollusk in the family Rissoidae.

Description

The length of the shell is of small size, the shell is conic-ovate, thick, has beaded spiral cords and convex whorls. It is imperforate, vitreous, and colourless.
Protoconch: 1,5 whorls.
Teleoconch: three convex whorls, suture impressed and wide. In the last whorl there are 7 spiral cords with strongly circular beads when they are crossed by about 20 weaker axial ribs. The distance between 2° and 3° cord is larger. The mouth of the snail is oval in shape, with the outer lips having a strong varix. The snail has no umbilicus, while the Operculum and soft parts are unknown.

Distribution

This species occurs in the Indian Ocean off Southern Madagascar; Réunion; Mauritius.