Swollen river mussel

Unio Tumidus

The Great River clam, even overblown river mussel ( Unio Tumidus ) is a large freshwater mussels, which applies in Germany of the early 21st century as an endangered species.

Features

The body of the shell is bean - or kidney- shaped and is usually 8 to 10 inches long, in rare exceptions, to 12 inches. The shell is usually brown or black and often encrusted with lime or a black iron-manganese coating. The soft body of freshwater mussel is bright and the back part is the large inlet opening and an outlet opening located above smooth-edged. The front part of the housing is buried by the shell, so that only the in-and outflow opening at the back sticking out. It has a foot for locomotion, they can stick out at the bottom between the flaps for locomotion. The Great River mussel can be very old. Single copies reach an age of over fifty years.

Life, the occurrence and distribution

She lives in both lakes as well as in slow-flowing rivers on sandy grounds. However, lakes, where they are particularly common in the lives affected by the wave impact riparian zone are preferred. She goes up to several meters deep. Known larger populations are made by the industry -induced strong river water pollution only in relatively clean lakes in northern Germany. So there are more occurrences in Schleswig-Holstein in the eastern hill country and in Mecklenburg- Vorpommern (eg in the Feldberg Lakes ). Here were z.T. still high stocking densities of up to 70 individuals per m2 observed. The ( original ) distribution area of ​​the Great River mussel extends in Europe from eastern France and western Switzerland through central Europe to northern Scandinavia ( the Arctic Circle ), and in the east to the Ural Mountains, the Danube from Vienna before she comes.