Physella acuta

Appearance

Snails in the family Physidae have shells that are sinistral, which means that if the shell is held with the aperture facing the observer and the spire pointing up, then the aperture is on the left-hand side.

The shells of ''Physella'' species have a long and large aperture, a pointed spire, and no operculum. The shells are thin and corneous and rather transparent.

Distribution

It was once thought that the indigenous distribution of ''Physella acuta'' is Mediterranean. However, when ''Physella heterostropha'' is considered to be a synonym, then the indigenous distribution of the species includes North America.

''Physella acuta'' is a common species which is common in all of North America and Europe. The species seems to have first spread through the Mediterranean regions and then more slowly into Northern Europe.

Habitat

This species lives in freshwater rivers, streams, lakes, ponds, and swamps.

''Physella acuta'' is frequently found in anthropogenic reservoirs, occurring in warm water discharges from power stations and in some rivers, but very rarely and not numerously in clay pit ponds. It can survive well under temporary harsh conditions , as long as they are short-lived.

Food

These snails eat dead plant and animal matter and various other detritus.

Because ''Physella acuta'' forages mainly on epiphytic vegetation and on the macrophytes, whereas other gastropods exploit the algal cover or phytobentos on the bottom, competition between ''Physella acuta'' and other gastropods appears to be minimal.