Alvania sanctipaulensis


Alvania sanctipaulensis is an extinct species of minute sea snail, a marine gastropod mollusc or micromollusk in the family Rissoidae.

Description

The shell of Alvania sanctipaulensis reaches a length of 3 mm and a diameter of 2.75 mm. It features a high spire and fine axial ribs typical of the genus Alvania. The surface is ornamented with spiral striations, and the aperture is oval with a continuous peristome. The shell morphology suggests an adaptation to shallow marine environments with soft substrates.

Distribution

Fossils of Alvania sanctipaulensis have been discovered in Oligocene strata of the Aquitaine Basin in southwestern France, particularly in sedimentary layers dated to the Chattian stage. The species likely inhabited warm, shallow marine coastal environments typical of that period.