Echinoderms

Fact file

Proper name: Phylum Echinodermata
Common name: Echinoderms (eck-i-no-derms)
Examples: Sea urchins, starfish, and sea lilies

Numbers of species: Over 6,000
Where they are found: Found only in the sea

Description: Echinoderms come in a range of shapes, but many have 'pentaradial symmetry'. This means you can divide their bodies into five similar parts ('penta' means five) - like the five arms of a starfish.

Need to know: Although they may look quite different from vertebrates, echinoderms are much more closely related to them than other invertebrates are.

Find out more about echinoderms with this puzzle
Find out more about fossil echinoderms

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