The most recent example is the little opossum shrimp ("Limnomysis benedeni"), only six to eleven millimeters long, which was found in 2006 in the Vorarlberg region of Hard, and can now be found almost all over Lake Constance. It comes from the waters around the Black Sea. It was presumably first transported by ships up the Danube before it spread into the Rhine river system and entered Lake Constance. The opossum shrimp, which occurs in many places in shoals of several million in winter, are already an influential link in the food chain in Lake Constance. They consume dead animal and plant material as well as phytoplankton, but are also eaten by fish themselves.