Reveal Universe on Instagram: "Arapaima is one of the largest freshwater fishes in the world, found mainly in the Amazon Basin. Its most notable feature is its extremely fast reflex system. The fish has a special pressure-sensing ability through its lateral line, which allows it to detect tiny water movements instantly. Because of this, it can react in a fraction of a second to anything approaching it. The arapaima’s body has strong muscle coordination and a streamlined shape, helping it turn an