Sci-fi planet inhabitants (4)
I believe the answer is:
apes
'sci-fi planet inhabitants' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for apes that I've seen before include "Imitates in every aspect" , "Imitates like primates" , "Species of primate" , "Peas (anag)" , "Large primates" .)