Spotting

Black Redstart species is split into 2 groups, Western for Europe and Eastern for Asia. Western are all grey/black with a red tail while Eastern are grey/black with red belly and tail. Scientifically they are separated by different sub-species, details can be found here http://www.birds.cornell.edu/clementsche...
Common names in this list are those in American usage and may differ from those in British usage found in many European and Asian books which often leave out prefixes and suffixes which were added by American authorities after early settlers had given similar names to different species.

The scientific name comes up as two different colors. I believe there are different looks depending on where it is found.