Cuttlefish, a sea animal related to the squid and octopus. It is not a fish but a mollusk. The cuttlefish is found in tropical and temperate seas. It has an oval body, somewhat flattened. The common cuttlefish (also called the common sepia) is 6 to 10 inches (15 to 25 cm) long and ranges in color from light gray to dark brown. Some species are much larger, attaining a length of more than two feet (60 cm). A thin flap of skin like a frilled fin runs along each side. There are two prominent eyes. The mouth is surrounded by eight arms and two longer tentacles that bear suckers, used to catch prey (fish and crustaceans) or attach the animal to some object.

CuttlefishCuttlefish are mollusks related to squids and octopuses.

While swimming about, the cuttlefish can regulate its buoyancy by controlling th amounts of liquid and gas contained within a specialized structure in its body—a porous, oval piece of shell called cuttlebone. The cuttlefish uses its side fins in swimming and can gain speed by squirting out water from a tube beneath the head. By this means, the animal darts rapidly backward. When alarmed, the cuttlefish ejects an inky fluid to cloud the water and confuse its predators.

The brown pigment sepia, used by artists, was originally prepared from the inky secretion of the cuttlefish Cuttlebone is a source of minerals for cage birds, which peck at it. Ground cuttlebone is sometimes used in making tooth powder. The cuttlefish is used as food in parts of Asia and is used as fish bait in many places.

Are Cuttlefish Really Fish?

No, cuttlefish are actually small mollusks. They are related to squids and octopuses. Like a squid, a cuttlefish has an internal shell.

Cuttlefish have oval bodies that can come in all sorts of colors, such as white, brown, orange, red, and green. Some cuttlefish even change color, depending on the way sunlight hits their bodies.

Like a squid and an octopus, a cuttlefish has eight arms. A cuttlefish also has two long tentacles. But unlike a squid, a cuttlefish can tuck its tentacles into pockets above its eyes.

The common cuttlefish is Sepia officinalis of the family Sepiidae.