Flaccid alien creature with suckers (6)

I believe the answer is:

limpet

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'creature with suckers' is the definition.
I can't judge whether this defines the answer.

'flaccid alien' is the wordplay.
'flaccid' becomes 'limp' (synonyms).
'alien' becomes 'et' (extra terrestrial).
'limp'+'et'='LIMPET'

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(Other definitions for limpet that I've seen before include "Proverbially clinging shellfish" , "Gastropod that sticks to rocks" , "A shellfish that sticks fast" , "Clingy person" , "Marine mollusc" .)

I've seen this clue in The Telegraph.

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