No radius remains of a fossilised creature (8)

I believe the answer is:

dinosaur

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'creature' is the definition.
(dinosaur is a kind of animal)

'no radius remains of a fossilised' is the wordplay.
'no radius' anagrams to 'DINOSAUR'.
However, I am not sure how this is indicated.

Can you help me to learn more?

(Other definitions for dinosaur that I've seen before include "Reptile is around, not really" , "Extinct reptilian animals" , "Prehistoric monster found on Darius" , "Large extinct reptile" , "Beast long gone" .)

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

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