The mola mola fish is also known as the ocean sunfish. This fish is HUGE!!
The ocean sunfish resembles a fish head with a tail. Its caudal fin(the back fin) is replaced by a rounded clavus, creating the body's shape. The main body is flattened, giving it a long oval shape when seen head-on (like in the picture). The pectoral fins (the fins on the side of a mola mola's head) are small and fan-shaped. However, the dorsal fin (the fin on the top of the mola) and the anal fin (the fin on the bottom of the mola) are lengthened, often making the fish as tall as it is long. Mola Mola's up to 3.2 meters (10.5 feet) in height have been recorded. That is one big fish!!
The Mola Mola has an average length of 1.8 meters (5.9 feet), and an average weight 2,200 pounds! But some Mola's have been observed and weigh up to 5,100 pounds!
Even though sunfish descended from bony ancestors, its skeleton actually contains largely cartilaginous tissues, which are lighter than bone, allowing it to grow to sizes impractical for other bony fishes. This is also proved by the fact that the largest fish (fishes and whales are two totally different things) in existence today is the whale shark, an entirely boneless fish.
Mola Mola's live in the ocean around the world, as seen in this description.
The fry (baby fish) are considerably spiny as seen in in the picture below. Once mature, the mola's sharp spines will disappear. They grow from being one tenth of an inch (that's the width of a DVD case) to a fully matured fish reaching up to 12 feet in length and 14 feet from fin to fin. Breeding is likely to take place in the tropical to subtropical regions of the ocean.
Mola Mola's mainly feed on salps, comb jellies, zooplankton, squid, crustacens, small fishes, fish larvae, and eel grass. This diet is poor in nutricion, forcing the sunfish to eat a lot of food to maintain its large size.
The sunfish can spit out and pull in water through its small mouth to tear apart soft-bodied prey. Its teeth are fused into a beak-like structure, allowing it to break up harder sea animals. In addition, pharyngeal teeth, located in the throat, grind food into smaller pieces before passing them to the stomach.
A mola mola's mouth
Here is a diagram of what the mola mola fish looks like:
Mola Mola's, just like fish, breathe from their gills. As you can see in this diagram, Mola's have gill slits very near to their eye.