What Fish Is This? :s

[akfox18]

so, I acquired 4 of these with a tank I bought. Apparently they're cichlids but goodness knows. They look prehistoric! They're funny little things. There's four of them and they just hang about together nearer the top of the tank. They also come and say hello/attack/bite you whenever you put your hand in the tank! 
Hoping someone can help! 

 

 

[techen]

Can't remember the name but you ought to know moreso with those fish !