Crossword Genius

Pope found in English river — a kind of fish (7)

Ross

I believe the answer is:

teleost

'a kind of fish' is the definition.

'pope found in english river' is the wordplay.
'pope' becomes 'Leo' (papal name of several popes).
'found in' is an insertion indicator.
'english river' becomes 'Test' (River Test in Hampshire).
'leo' inserted into 'test' is 'TELEOST'.

(Another definition for teleost that I've seen is " Bony fish such as herring or carp".)

I've seen this clue in The Guardian.
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