Sea Star (Asteroidea)
Size – There is a wide variety in length, but on average, about 5 to 10 inches.(12-24cm)
Perhaps the best known, or most popular, Echinoderm is the beautiful Starfish also known as the Sea Star.
These star-shaped marine animals belong to the class Asteroidea. Most species have five arms, but there are some that contain more, even up to 10-15. They also have the ability to regenerate limbs or damaged parts.
From frigid to tropics, they can be found on the seabed of all the world’s oceans. Their habitat ranges from kelp forests, coral reefs, and tidals pools to the deep seafloor of at least 20,000 feet. The greatest range in species is found in coastal waters.
They generally eat microalgae, sponges, snails, or other small ocean animals.
They use their tube feet to traverse, and are very opportunistic eaters. They have complex life cycles and can produce both sexually and asexually. Their lifespan varies between species, but on average around 10 years, but some can live up to 30+.
Sometimes referred to as Asteroids due to them belonging to the class Asteroidea, there are over 1,500 species of Starfish.
They are considered a keystone species due to their great adaptability to all environments.
The Common Starfish is sometimes used to test the quality of the environment, otherwise referred to as a bioindicator.