The Black Tetra (scientifically known as Gymnocorymbus Ternetzi) is a freshwater fish that is part of the Characin family. It is also commonly known as the Black Skirt Tetra, the Petticoat Tetra, the High-finn Black Skirt Tetra and the Black Widow Tetra. It is native to Brazil, Argentina and Bolivia. The Black Tetra has a tetragonal body shape and has a greyish coloration - the bottom half of its body is a blackish color that fades into a light grey...