No trap for fish, possibly (6)
I believe the answer is:
tarpon
'fish possibly' is the definition.
'tarpon' can be an answer for 'fish' (I've seen this before). I'm not certain of the 'possibly' bit.
'no trap' is the wordplay.
'no trap' can be anagrammed to 'TARPON'.
Though, I am not clear how the anagram is indicated.
'for' acts as a link.
Can you help me to learn more?
(Other definitions for tarpon that I've seen before include "Large silvery game fish of coastal waters off Florida" , "Great fish of Florida" , "No part for this large fish" .)