What's the name of this bug?
It looks like it's the other way around to me. More likely a member of Auchenorrhyncha, which includes cicadas and leafhoppers. I say this judging from the leg structure, abdomen shape, and the eyes. It is however missing wings... perhaps they were removed by another organism?

It somewhat looks like Philaenus spumarius, the "meadow froghopper" which is found in Germany. As for the green tail bit, I am not all that sure.