i think it's an African Snakehead from what i see in the channa species guide sticky tread, but i dun think it's a african snakehead as its back fins are separated and not joined together.
its Parachanna obscura, an african snakehead species. German name translated in English is darkbelliied snakehead.
The "two" back fins are result of an injurie in the very early youth of this fish.