Superior newspapers covering South American city (8)
I believe the answer is:
prioress
'superior' is the definition.
(prioress is a kind of superior)
'newspapers covering south american city' is the wordplay.
'newspapers' becomes 'press' (I've seen this before).
'covering' is an insertion indicator.
'south american city' becomes 'rio' (I've seen this before).
'press' enclosing 'rio' is 'PRIORESS'.
(Other definitions for prioress that I've seen before include "Superior nun" , "Religious leader" , "A senior member of a female religious house" .)