As gigantic as the ocean sunfish can be, it still seems like only half a fish.
Sunfish, or mola, develop their truncated, bullet-like shape because the back fin which they are born with simply never grows. Instead, it folds into itself as the enormous creature matures, creating a rounded rudder called a clavus. Mola in Latin means "millstone" and describes the ocean sunfish’s somewhat circular shape. They are a silvery color and have a rough skin texture.
The mola are the heaviest of all the bony fish, with large specimens reaching 14 feet (4.2 meters) vertically and 10 feet (3.1 meters) horizontally and weighing nearly 5,000 pounds (2,268 kilograms). Sharks and rays can be heavier, but they're cartilaginous fish.
Mola are found in temperate and tropical oceans around the world. They are frequently seen basking in the sun near the surface and are often mistaken for sharks when their huge dorsal fins emerge above the water. Their teeth are fused into a beak-like structure, and they are unable to fully close their relatively small mouths