Identifying British freshwater snails: shape of shell.

Freshwater snails » Shell shape
 
The shell may take four basic shapes. Please click on the image below which is most like the shell you wish to identify.

Please note: the images below are not all to the same scale.

Shell shaped like a cap or shield.

Shell shaped like a cap or shield without any sign of helical coiling.

Mouth aperture shaped like a half moon.

Shell with very a low spire and the mouth aperture is half-moon shaped.

Shell taller than wide.

Shell taller than wide. Coiling may be either left-handed (sinistral) or right-handed (dextral). An operculum may or may not be present. (See glossary for details of terms).

shell coiled in one plane

Shell coiled more or less in one plane, making it wider than it is tall. An operculum may or may not be present.