Two-Ton Sunfish Species Is Incredibly Bizarre

Image: César Villarroel, ExploraSub

It took biologists four years to uncover this two-ton sunfish — but by the looks of it, it was well worth the wait. 

The Mola tecta or hoodwinker sunfish is the fourth discovered species of sunfish, the largest bony fish in the world. While genetic samples initially suggested a fourth species, it had yet to be recognized in the field and thus began an extensive hunt for physical evidence.

Sunfish in general are some of the oddest looking fish under the sea. They have flat, inflexible bodies except for their fins, no tail, and the development of strange bumps around their facial features.

A lumpy sunfish species. Image: Per-Ola Norman, Wikimedia Commons

While not definitively rare, sunfish are a hard species to study because of their typical marine behavior, which involves diving hundreds of feet deep to hunt and then flopping to the surface to lay on their sides in the sunlight (attributing to their namesake). Their range encompasses the colder parts of the Southern Hemisphere including New Zealand, South Africa, and Chile.

PhD student Marianne Nyegaard led the team of researchers associated with the hoodwinker’s discovery. These impressive animals can grow to be over 10 feet long, 14 feet tall, and weigh over 5,000 lbs. Unlike their relatives, these sunfish don’t develop unusual lumps as they age and instead maintain their juvenile body size. They have agape mouths and fused teeth that form a scooping shape, similar to a beak.

The hoodwinker sunfish had been hiding in plain sight for centuries and has finally been revealed to fill in the gaps of missing sunfish DNA.

The full study is published in the Zoological Journal.