an african tiger fish, being injected with something. Its not a primitive fish, its a very modern fish. Its from the Characin family of fishes, with the tetras and piranhas, among other species.
ATFs get from 2'-6' long depending on specie. They are generally too active and large to keep for life in any conventional-sized tank.
Very cool! When I have the space for another tank, (My wife sighs) I am going to set up a large aquarium or maybe paludarium with snakeheads and tigers.
Snakeheads and ATFs will be hard to do. You can put them together when small only to have the snakeheads outgrow the ATFs quickly and have them for a snack.