Physiidae-The shells of the species of this family are coiled in an anti-clockwise direction.The tentacles are slender.If they are disturbed they shake their shell.

Aplexa hypnorum(Linnaeus,1758) Shell cone shaped,sharp pointed,brown or yellowish,glossy.It is 12mm high and 5mm wide The animal is black or dark-grey and has slender tentacles.The eggs are laid in May-July. The snails live for about a year and feed on algaes and waterplants in sweet or brackish water. In Europe.

Physa fontinalis(Linnaeus,1758) Shell is egg-shaped,the top is flat and the color yellowish or light-brown. It's 15mm in height and 9mm in width.The body is grey with whitish tentacles. When the animal is disturbed it shakes its shell.The eggs are laid in April-June and August till October. They feed on algaes and plantparts in sweet or brackish water. In Europe,North- and Central-Asia and Canada.

Physella acuta(Draparnaud,1805) Shell is egg shaped,the top pointed and the color light-yellow or brownish. It is 19mm high and 14mm wide.The animal is light-grey and feeds on carrion or plants in canals and lakes.This species prefers warm water. In Southwestern Europe,North-Africa,imported in other places. ...

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