Rutland fossil reanimated so a danger (3,6)

I believe the answer is:

sea dragon

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'rutland fossil' is the definition.
I know nothing about this answer so I can't judge whether it can be defined by this definition.

'reanimated so a danger' is the wordplay.
'reanimated' is an anagram indicator (letters are moved around or 'animated').
'so'+'a'+'danger'='soadanger'
'soadanger' with letters rearranged gives 'SEA-DRAGON'.

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I've seen this clue in The Independent.

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