Different kinds of Starfish

　　The echinoderms are a group of animals that includes starfish, urchins, feather stars, and sea cucumbers. They are simple animals, lacking a brain and complex sensing organs. Echinoderms are characterized by their radial symmetry and a central mouth. Although a sea urchin looks round, closer inspection reveals that it is nothing more than a starfish with its legs wrapped inwards to form a sphere. The echinoderms are found in a stunning variety of shapes and colors, and are found decorating coral reefs around the world. Some of these animals are carnivorous, feeding on corals and scavenging the ocean floor. Certain species of starfish actually extend their stomachs into their unwary victims in order to digest them. The feather stars and sea cucumbers are mainly filter feeders, catching what ever they can find floating in the ocean currents. All of the echinoderms move around with the use of thousands of tiny tube feet, many of which have suction cups on the ends. Many of the urchins have developed extremely sharp spines as a means of protection. Below is a listing of some of the most common reef-dwelling echinoderms.

1.Cushion Star
The cushion star is a thick-bodied species of starfish with short legs. It ranges in color from brown to orange, red, and yellow. Its hard shell is covered with raised knobby spines. This starfish is grows to a diameter of 10 inches, and is found on the sandy bottoms in the Atlantic waters from South Carolina to Florida. Its hard shell makes it a popular species among shell collectors.
2.Sunflower Starfish
The sunflower star is among the larger of the starfish species. With its 24 arms, it can reach a diameter of over 2 feet! The color of this starfish can range from purple to red, pink, brown, orange, and yellow. It is common along the Pacific coast and can be found along the rocky sea bottoms from Alaska to southern California.
3.Pacific Starfish
This brightly colored starfish is a common species found along the western coast of the United States and Canada. It can range in color from red to orange, yellow, and purple. This starfish grows to a diameter of about 8 inches, and is found under rocks where it feeds on small sponges and algae.
4.Short Spined Starfish
The short spined starfish is a coldwater species found in the northern waters from the Arctic to Cape Hatteras. They can be seen in a wide range of colors from orange to red, purple, yellow, and white. Dark red varieties are sometimes known as blood stars. They can be found scavenging along the rocky sea bottom.
5.Orange Starfish
This colorful orange and red starfish is one of the most common species. Its colorful markings and docile nature make it quite popular among aquarium hobbyists. This starfish grows to about 4 inches in diameter, and is commonly found in the Indian Ocean near Indonesia where is feeds on small sponges and algae.
There are some other kinds of Starfish,such as Reticulate Brittle Star,Basket Star,Feather Starfish and so on.If you are interested with them,You can search the Internet for their detail information.