The Ocean Sunfish (Mola mola) is a bizarre pelagic fish, the largest bony fish in the world, with specimens observed up to 3.3 m (13 ft 10 in) in length and weighing up to 2,300 kg (5070 lbs). A member of order Tetraodontiformes, it is the type species of its genus.

Ocean Sunfish are commonly mistaken for sharks, as they often swim close to the surface and have dorsal fins that stick up out of the water in a shark-like fashion. However, Ocean Sunfish feed on zooplankton (along with small fish and other marine life), and are commonly friendly towards people, such as divers who venture into their habitat. They are found in warm and temperate zones of all oceans, including the Eastern Pacific and the eastern and western Atlantic.

Unusually, Mola mola uses its long, thin dorsal and anal fins for propulsion; it lacks a caudal fin, having in its place a rudder-like structure, the clavus. Its fry resemble miniature pufferfish, a hint at the species's place in the evolutionary tree.

While the flesh of the Ocean Sunfish is considered a delicacy by some, it contains neurotoxins similar to those of other poisonous Tetraodontiformes.

The Ocean Sunfish is also known as the marine sunfish, the moon fish, or simply by its specific name, mola (Latin for "millstone", which it was said to resemble). It has various obsolete binomial synonyms; its original name was Tetraodon mola.

Sunfish eat comb-jellies, zooplankton, squid, and crustaceans. They live in the eastern pacific and atlantic. Their predators are orcas, sea lions, dolphins and marlins. They are thought to live for over 10 years.

The freshwater sunfishes (family Centrarchidae) are unrelated; for other fishes known as "sunfish", see Sunfish.

References:

• FishBase Mola mola
• ITIS Mola mola