About Pseudosuccinea columella (Say, 1817)
Pseudosuccinea columella is a snail species whose shell is quite similar in appearance to shells of the genus Succinea, which is classified in a different family. The shell of Pseudosuccinea columella is horny brown, thin, translucent, fragile and marked with very fine striae. It has a pointed apex, 3.5 to 4 weakly convex whorls, and a shallow suture between the whorls. The final whorl makes up most of the shell's volume. The shell's aperture is ovate. Its upper palatal margin descends steeply. The columellar margin is only reflected at its upper section, while the lower columellar margin is sharp and straight. The shell ranges from 8 to 13 mm in width and 15 to 20 mm in height. The soft body of the animal is dusky and marked with whitish spots. The eyes are small and black, and they are positioned at the inner base of the tentacles. The haploid chromosome number for this species is 18 (n=18). In its native North America, Pseudosuccinea columella inhabits stagnant waters, edges of lakes and ponds, muddy and slow-moving streams, and lives among lily pads and reeds, on sticks and on mud. In Europe, the species is found predominantly in greenhouses, and sometimes in outdoor habitats in Austria and Hungary. It requires warm water and cannot survive typical Central European winter temperatures. Individuals can also be found above the waterline on floating leaves of aquatic plants; a population has been recorded in a spring near a road in northern Greece.
