Suddenly gets angry, obscure fish appearing in reverse (8)

I believe the answer is:

flipside

'reverse' is the definition.
(less important side of a vinyl record)

'suddenly gets angry obscure fish' is the wordplay.
'suddenly gets angry' becomes 'flips' (to flip is to suddenly become angry).
'obscure fish' becomes 'ide' (alternative term for orfe, a type of fish).
'flips'+'ide'='FLIPSIDE'

'appearing in' acts as a link.

(Another definition for flipside that I've seen is " reverse".)

I've seen this clue in the Independent.

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