Of the many creatures in the ocean, starfish, the misnamed stars of the ocean, are one of those that have the most unique features.

Starfish are colorful sea organisms that live in aquatic environments.

There are almost 2,000 different species of starfish, each with its distinctive size, shape, and color, be it blue, purple, pink, or orange.

These star-shaped sea critters are coated in a variety of fascinating patterns, including stripes, swirls, and even some that resemble flowers.

These fascinating sea stars can be discovered in kelp beds, seagrass, coral reefs, tide pools, and coral reefs.

Starfish only survive in saltwater. Additionally, they cannot endure being without water for more than a few minutes.

Here are other facts about starfish:

Not Fish: Sea Stars

The name "starfish" is deceptive. Starfish are invertebrates because they lack backbones, just as sand dollars and sea urchins.

Fish are vertebrates, which puts them in a distinct class from starfish. Sea stars, which pays homage to the five limbs that a lot of the species frequently have, is the more appropriate term for starfish.

Some are Not Star-Shaped

Some types of starfish can have several more limbs than the five that the common starfish have.

For instance, the National Park Service says that the starfish known as the crown of thorns (Acanthaster planci) can grow up to 21 arms.

Tube Feet


Starfish can move about because of hundreds of tiny suction cups resembling feet. They also use this feature for feeding.

Additionally, the glue-like material in these suction cup feet helps them adhere to objects like rocks so they won't fall off or be washed away by the waves.

They can hold onto their food thanks to the small suction cups on the backs of their legs. These feet also aid in the opening of mussels and clams.

Regenerating Lost Limbs

In times of injury, such as when they are struck by a rock from breaking tides, starfish can regenerate severed limbs. Even though it can take up to a year, starfish can regenerate their entire bodies from only one arm and at least a fifth of their central disk.

Few animals can regenerate their neurons as starfish can, which is another remarkable ability.

No Blood

The circulatory system of starfish is made of water, as opposed to blood. This system, which is typical of echinoderms like starfish and sea cucumbers, is made up of canals linking tube feet that circulate seawater inside the body of the starfish. Its nervous system receives nutrients from filtered seawater.

Carnivorous

These adorable critters eat more than just plants and algae. It is common knowledge that starfish devour animals such as sick or injured fish, whole oysters, mussels, clams, and even sand dollars.

Starfish occasionally exhibit aggressive cannibalism. A research published in the journal Ecology in 2021 found that young starfish have been observed to consume one another.

Stomach Envelopes Prey

External digestion occurs in starfish. Once their food has been consumed, they spread their stomach out of their mouth and enclose their victim in it. They later force their prey towards their digestive glands after partially digesting it to finish eating.

Eyespots

Each of the tips of the limbs of a starfish has an eye spot. The image that the animals see is made up of one pixel from each of these eyespots.

Starfish have many eyespots on each of their legs, allowing them to observe everything around them simultaneously, Treehugger reports.