The are Central American actually Most of them look like Convict Cichlids, the ones with red bellies are females.
In picture 1, that could be something else or it could just be stress markings? Then in the last pic on the plants on the left it looks like that could be a different species as well?
What size tank do you have? And what is your water like? These guys will like it hard, with a neutral to high ph and slightly cooler than some other fish. Do you have any other fish in with them?
Also, these guys are prolific breeders so do you have plans for when you end up with fry? Is this something you are prepared for?