My heart skipped a beat when I first heard about the Moonfish. Really? A MOON fish? I was soon scouring the net for pictures and what I saw, made my day. Also known as Opah, the Moonfish stays true to its name with a silver scaled, speckled round body that can grow up to 6 feet (1.8 meters) long. Although its orange-red fins are relatively small in proportion, they’re quite strong and flap continuously as the fish swims in the ocean.
Moonfish are extremely shy deep-sea dwellers that don’t congregate in large groups and are rare to spot. What’s more interesting is that the Opah is said to be the first warm-blooded fish ever discovered. While most fish are ectotherms -meaning they require heat from the environment to stay toasty- the Moonfish is an endotherm, i.e it keeps its own temperature elevated even as it dives to chilly depths of 1,300 feet (396 meters) in temperate and tropical oceans around the world. Click here for more scientific info.
The study of fish is known as Ichthyology – from Greek: ikhthus meaning “fish”; and logos meaning “study”.