Common sunstar and a brittlestar on the seabed


Echinoderms are a plylum of animals that includes starfish, sea urchins and sea cucumbers. They are radially symmetric marine creatures composed of identical segments rather than left/right mirroring. The most familiar is a typical starfish, which has five identical legs radiating out from its body.

Scientific name: Echinodermata

Rank: Phylum

Common names:

  • Echinodermata,
  • Sea lilies,
  • starfish and allies

Watch video clips from past programmes (1 clip)

In order to see this content you need to have an up-to-date version of Flash installed and Javascript turned on.

Explore this group


  1. Life
  2. Animals
  3. Echinoderms

BBC News about Echinoderms

  • Sea urchins tolerate acid water Sea urchins are likely to be able to adapt to increasingly acidic oceans caused by human-induced climate change, a study says.

BBC © 2014 The BBC is not responsible for the content of external sites. Read more.

This page is best viewed in an up-to-date web browser with style sheets (CSS) enabled. While you will be able to view the content of this page in your current browser, you will not be able to get the full visual experience. Please consider upgrading your browser software or enabling style sheets (CSS) if you are able to do so.