Echinoderms (Echinodermata) are a group of marine invertebrates that includes star fish, sea lilies, feather stars, brittle stars, sea cucumbers and sea urchins.
There are about 6000 species of echinoderms alive today. Most echinoderms are bottom-dwelling animals that exhibit a variety of feeding habits including filter feeding, scavenging and predation.
Present-day echinoderms are free-moving, but they evolved from sessile ancestors.
Our list of echidnoderms divided into these: