Alvania marchadi
Alvania marchadi is a species of minute sea snail, a marine gastropod mollusk or micromollusk in the family Rissoidae. It is named after Igor Marche-Marchad.
Description
The length of the shell ranges between 2.25 mm and 2.95 mm and is thickened with a strong rim. The exterior of the shell contains rigid spirals, while the interior is smooth.The protoconch has 1-3.1.5 convex whorls and "7 spiral flat cords...formed by minute granules".
The teleoconch has 3.3-4.2 convex wholes with "strong, widely spaced, nearly vertical axial folds." The body whorl is rounded with eight spiral and axial folds that fade "towards the periumbilical area".