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

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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.