The species in this family are hermaphroditic.They have a feather shaped gill.The head has a long snout.The foot is rounded in the back and split in two short parts in the front.

Valvata piscinalis(Müller,1774) The shell is cone or bowlar shaped about 6 mm high and pale-yellow-green. The body is white with long thin tentacles.The eggs are laid in March-July and hatch after 2-4 weeks.A high number of snails die after laying eggs. Snails born in the summer reproduce the next summer,in the winter they hibernate in mud.Part of the adult snails survive the winter and reproduce in the summer. They live up to 2 years. They feed on bacteria in calm or streaming water in Europe and western Asia.

Valvata cristata(Müller,1774) The shell is shaped like a disc and about 1,5mm high and 3,5mm wide. In calm,sweet water in Europe.

Valvata tricarinata(Say) The shell is tan colored or greenish with the whorls flattened,the umbilicus is deep. Height is 2-3 mm,width 3-5 mm. In lakes and rivers in Canada,Northeastern US to Virginia. ...

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