Helix vortex Linnaeus, 1758 Anisus vortex is a species of small freshwater snail, an aquatic gastropod mollusk in the family Planorbidae, the ram's horn snails and their allies.

On the top, the whorls are flat, separated only by a slightly pronounced seam.

On the bottom, however, the whorls are more curved and separated by a distinct suture.

The range of this species is from Europe across the Palearctic to Siberia.

It occurs in countries and islands including: