Well yes, it is a bit obscure one, the manufacturer, it didn't last for too long, however it has one great distinction in giving Gerhard Fieseler his first chance to work on aircraft design.
The mystery plane is an 'Erka' 25/32, or officially
Raab-Katzenstein RK.25/32 Ruhrland, an upgraded version of 'Erka' 25 (open cockpit, Cirrus engine) race plane. The photo was taken in Berlin, during the 1932 Circuit of Europe race.
This particular machine was not designed by Gerhard Fieseler, but RK.26 Tigerschwalbe aerobatic plane was. After Raab-Katzensteni went bust, Fieseler founded his own company and continued to build this plane as Fieseler F.1, as well as an improved variant F.2 which he used to win many aerobatic competitions. Later, of course, Fieseler's company went on to design many important and well known aircraft.
If anyone has the next question prepared, please go ahead an post it, i got nothing at the moment.