The Green Terror Andinoacara rivulatus (previously known as Aequidens rivulatus) is a most beautiful fish with an overall green and blue metallic sheen. In addition, they have a magnificent array colors that can be purple, pink, red and/or electric blue. The males are the most colorful of this species and develop a brilliant red edging on their tail fin, but the the females are also quite striking. They are also known as the Orange Saum, Gold Saum, amd White Saum.
This fish is similar to its close cousin, Andinoacara stalsbergi, which is also called a Green Terror. In fact, A. stalsbergi was previously included in A. rivulatus until 2009, when it was described as it's own species. Although the Green Terror, A. rivulatus, grows slightly larger, the best way to determine the difference between the two fish is in the coloring of the scales and fin edging. On A. rivulatus, the scales have a lighter blue to green edge with a dark center, and their dorsal and caudal fins have a thick orange or white edging. The scales of A. stalsbergi are reversed, with a dark blue to green center and a dark edging, and the fins have a thin white edging.
https://animal-world.com/encyclo/fresh/cichlid/GreenTerror.php