Hello, can you enlighten me more about Micropterus?
There are many genuss' of fish, Micropterus is one of the freshwater fish in the sunfish family. 
When was it first discovered?
Well it's a pretty popular fish.  They're called black bass, and distributed throughout a large area east of the rocky mountains, all the way from Hudson bay in Canada to Mexico.  That makes it hard to say when they were first discovered.
So it's eaten in North America I would say?
Oh yeah they are known to be strong fighters, that means their meat is probably firm, which makes for a very tasty fish.
How much does a kilo of the fish cost?
I couldn't tell you specifics, but they are called black bass though often confused with trout.  It would probably be a similar price to regular bass?