The phylum Echinodermata consists of about 7000 living species but there are a further 13,000 extinct species dating back to the Cambrian. They are basically pentaradially symmetric which means that they are five-sided, and all live in the sea. They include the sea lilies, the starfish, the sea daisies, the brittle stars, the sea urchins and the sea cucumbers.- Category ID : 418397
Descriptions of the major species of Echinodermata (starfish, brittle star, sea urchin, feather star, sea cucumber) with illustrations and links to photos.
Project based at the Natural History Museum, London, aiming to provide information for amateurs and the scientific community on this major group of marine invertebrates with a long fossil record.