Change each dream into starfish and sea urchins? (13)

I believe the answer is:

echinodermata

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'starfish and sea urchins?' is the definition.
I can't judge whether this definition defines the answer.

'change each dream into' is the wordplay.
'change' is an anagram indicator.
'each'+'dream'+'into'='eachdreaminto'
'eachdreaminto' anagrammed gives 'ECHINODERMATA'.

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I've seen this clue in the Sydney Morning Herald.

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