Anisus vorticulus
Petite plate screw
The Dainty plate screw ( Anisus vorticulus ) is a small water lung worm ( Basommatophora ) from the family of the plate screw ( Planorbidae ). In Germany, she was elected to the soft animal of the year 2011.
Features
The housing is only 0.7 to 0.8 mm high, and of up to 5 mm in diameter. It has 5 to 5.5 convolutions that are convex on the upper side and the underside. On the last deal a blunt edge is formed centrally. The top of the case is slightly dented, the bottom is almost flat. The animals are about 1 year old.
Habitat and Distribution
The Dainty dishes snail lives in clear, stagnant water on plants, preferably in small pools, which are covered with duckweed ( Lemna ). It comes from before Western to Eastern Europe. You lack in Scandinavia.
Similar Species
The Hot Plate screw ( Anisus vortex ) is slightly larger and has a sharper keel.
Endangering
The Dainty plate screw ( Anisus vorticulus ) is threatened in Germany and Switzerland extinction. In Austria it is classified as endangered.