The green terror (Aequiens rivulatus) is a colorful freshwater fish in the cichlid family. The fish originate on the Pacific side of South America in the coastal waters from the Tumbes River in Peru to the Esmeraldas River in Ecuador. Males reach lengths of 30 cm (12 in.) and females can, too. However, females stop growing the first time that they spawn and will remain at that length for the rest of their life. Females are sexually mature at around 4.5 in., and therefore that is the smallest length that they can remain at. This causes a misconception that males are larger than females.