Animals in rainforest or at sea, understood, succeeded (3-4)

I believe the answer is:

aye-ayes

'animals in rainforest' is the definition.
(aye-aye is a type of primate)

'at sea understood succeeded' is the wordplay.
'at sea understood' becomes 'ayeaye' (nautical term for 'yes' or 'understood').
'succeeded' becomes 's' (genealogical abbreviation).
'ayeaye'+'s'='AYE-AYES'

'or' is the link.

I've seen this clue in The Times.

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