American Ribbed Fluke Snail

The shell quite closely resembles shells in the genus Succinea, which belongs to a different family. The shell of Pseudosuccinea columella is horny brown, thin, translucent, fragile and very finely striated. The apex is pointed. The shell has 3.5–4 weakly convex whorls with a shallow suture. The last whorl predominates. The aperture is ovate. The upper palatal margin descends steeply. The columellar margin is reflected only at its upper section; the lower columellar margin sharp and straight. The width of the shell is 8–13 mm. The height of the shell is 15–20 mm.

The animal is dusky with whitish spots. The eyes are small and black and are located at the inner base of the tentacles. The haploid number of chromosomes is 18 (n=18).

In North America, Pseudosuccinea columella lives in stagnant waters, at the edges of lakes, ponds, muddy and sluggish streams, among lily pads and reeds on sticks and mud. In Europe it occurs predominantly in greenhouses, but also sometimes in outdoor habitats (Austria, Hungary). It needs warm water and does not survive Central European winter temperatures. It is also found above the water on floating leaves of aquatic plants; in northern Greece it was found in a spring near a road.