Ecrobia ventrosa, common name spire snail, is a European species of small brackish water snail with a gill and an operculum, an aquatic gastropod mollusk in the family Hydrobiidae.

[2] This species occurs on the coasts of: The distribution type is coastal Mediterranean–Atlantic.

Smaller shells with 5 whorls are slightly less slender than those of Hydrobia neglecta.

The aperture is rounded upside (or only slightly pointed) and attached to the last whorl.

The shell is very finely striated and in colour translucent, glossy yellow-brown, usually hidden by a matt deposit.